Spring clean/refactor of NPU driver

These changes mostly focus on creating a better structure
for the driver. Creating a better separation between driver
and device(s).

A short summary of what this commit contains:

    - Move driver specific defines from device to driver
    - Prefix device functions with ethosu_dev
    - Remove device specific register access' from driver
    - Remove device specific debug/dump functions
    - Add function prototypes for weak functions
    - Remove legacy ARM_NPU_STUB support
    - Rename ethosu_device.c to ethosu_device_u55.c
    - Remove redundant irq handler prototype
    - Remove (deprecated) hardcoded instance ethosu_drv

    - Simplify versioning API
      Split driver version and hardware version/information so
      that driver version can be queried without a driver instance.

    - Improve and simplify logging
      Make warning the new default severity level to print and
      reduce severity levels to:
        err
        warning
        info
        debug

    - Add severity prefix to log lines. Error messages print file
      and line number, debug messages print function by default.
    - Clarify some log messages

    - Small optimizations and bugfixes

Change-Id: I2dfbfc3a40d7eca133c82f187f422325e1e6d314

8 files changed, 1148 insertions, 1676 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index b364716..9852ae4 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,5 +1,5 @@
 #
-# Copyright (c) 2019-2020 Arm Limited. All rights reserved.
+# Copyright (c) 2019-2021 Arm Limited. All rights reserved.
 #
 # SPDX-License-Identifier: Apache-2.0
 #
@@ -28,8 +28,8 @@ option(DRIVER_PMU_AUTOINIT "Enable PMU boot auto-initialization" OFF)
 
 set(CMSIS_PATH "${CMAKE_CURRENT_SOURCE_DIR}/../cmsis" CACHE PATH "Path to CMSIS.")
 
-set(LOG_NAMES emerg alert crit err warning notice info debug)
-set(ETHOSU_LOG_SEVERITY "info" CACHE STRING "Driver log severity level ${LOG_NAMES}")
+set(LOG_NAMES err warning info debug)
+set(ETHOSU_LOG_SEVERITY "warning" CACHE STRING "Driver log severity level ${LOG_NAMES}")
 set_property(CACHE ETHOSU_LOG_SEVERITY PROPERTY STRINGS ${LOG_NAMES})
 
 #
@@ -53,7 +53,7 @@ include_directories(${CMSIS_PATH}/CMSIS/Core/Include)
 # Build driver library
 add_library(ethosu_core_driver STATIC)
 target_include_directories(ethosu_core_driver PUBLIC include)
-target_sources(ethosu_core_driver PRIVATE src/ethosu_driver.c src/ethosu_device.c src/ethosu_pmu.c)
+target_sources(ethosu_core_driver PRIVATE src/ethosu_driver.c src/ethosu_device_u55.c src/ethosu_pmu.c)
 
 # Set the log level for the target
 target_compile_definitions(ethosu_core_driver PRIVATE ETHOSU_LOG_SEVERITY=${LOG_SEVERITY})
diff --git a/include/ethosu_device.h b/include/ethosu_device.h
index 0221ad1..dad88ef 100644
--- a/include/ethosu_device.h
+++ b/include/ethosu_device.h
@@ -34,10 +34,7 @@ extern "C" {
  * Defines
  ******************************************************************************/
 
-#define ETHOSU_DRIVER_VERSION_MAJOR 0  ///< Driver major version
-#define ETHOSU_DRIVER_VERSION_MINOR 16 ///< Driver minor version
-#define ETHOSU_DRIVER_VERSION_PATCH 0  ///< Driver patch version
-#define ETHOSU_DRIVER_BASEP_INDEXES 8  ///< Number of base pointer indexes
+#define ETHOSU_BASEP_INDEXES 8 ///< Number of base pointer indexes
 
 #ifndef ETHOSU_PMU_NCOUNTERS
 #define ETHOSU_PMU_NCOUNTERS 4
@@ -82,13 +79,10 @@ struct ethosu_id
 
 struct ethosu_config
 {
-    struct
-    {
-        uint32_t macs_per_cc;        ///< MACs per clock cycle
-        uint32_t cmd_stream_version; ///< NPU command stream version
-        uint32_t shram_size;         ///< SHRAM size
-        uint32_t custom_dma;         ///< Custom DMA enabled
-    };
+    uint32_t macs_per_cc;        ///< MACs per clock cycle
+    uint32_t cmd_stream_version; ///< NPU command stream version
+    uint32_t shram_size;         ///< SHRAM size
+    uint32_t custom_dma;         ///< Custom DMA enabled
 };
 
 /**
@@ -156,12 +150,12 @@ enum ethosu_error_codes ethosu_dev_init(struct ethosu_device *dev,
 /**
  * Get device id.
  */
-enum ethosu_error_codes ethosu_get_id(struct ethosu_device *dev, struct ethosu_id *id);
+enum ethosu_error_codes ethosu_dev_get_id(struct ethosu_device *dev, struct ethosu_id *id);
 
 /**
  * Get device configuration.
  */
-enum ethosu_error_codes ethosu_get_config(struct ethosu_device *dev, struct ethosu_config *config);
+enum ethosu_error_codes ethosu_dev_get_config(struct ethosu_device *dev, struct ethosu_config *config);
 
 /**
  * Execute a given command stream on NPU.
@@ -175,11 +169,11 @@ enum ethosu_error_codes ethosu_get_config(struct ethosu_device *dev, struct etho
  * \param[in] num_base_addr    Number of base addresses.
  * \return                     \ref ethosu_error_codes
  */
-enum ethosu_error_codes ethosu_run_command_stream(struct ethosu_device *dev,
-                                                  const uint8_t *cmd_stream_ptr,
-                                                  uint32_t cms_length,
-                                                  const uint64_t *base_addr,
-                                                  int num_base_addr);
+enum ethosu_error_codes ethosu_dev_run_command_stream(struct ethosu_device *dev,
+                                                      const uint8_t *cmd_stream_ptr,
+                                                      uint32_t cms_length,
+                                                      const uint64_t *base_addr,
+                                                      int num_base_addr);
 
 /**
  * Check if IRQ is raised.
@@ -188,13 +182,13 @@ enum ethosu_error_codes ethosu_run_command_stream(struct ethosu_device *dev,
  *                             - 1 IRQ raised
  * \return                     \ref ethosu_error_codes
  */
-enum ethosu_error_codes ethosu_is_irq_raised(struct ethosu_device *dev, uint8_t *irq_status);
+enum ethosu_error_codes ethosu_dev_is_irq_raised(struct ethosu_device *dev, uint8_t *irq_status);
 
 /**
  * Clear IRQ status.
  * \return                     \ref ethosu_error_codes
  */
-enum ethosu_error_codes ethosu_clear_irq_status(struct ethosu_device *dev);
+enum ethosu_error_codes ethosu_dev_clear_irq_status(struct ethosu_device *dev);
 
 /**
  * Get the 16 bit status mask.
@@ -210,14 +204,21 @@ enum ethosu_error_codes ethosu_clear_irq_status(struct ethosu_device *dev);
  *                                 bit7-15: reserved
  * \return                         \ref ethosu_error_codes
  */
-enum ethosu_error_codes ethosu_get_status_mask(struct ethosu_device *dev, uint16_t *status_mask);
+
+enum ethosu_error_codes ethosu_dev_get_status_mask(struct ethosu_device *dev, uint16_t *status_mask);
+
+/**
+ * Get current NPU status
+ * \return                     32 bit status value
+ */
+uint32_t ethosu_dev_get_status(struct ethosu_device *dev);
 
 /**
  * Get the 16 bit IRQ history mask.
  * \param[out] irq_history_mask    Pointer to the IRQ history mask.
  * \return                         \ref ethosu_error_codes
  */
-enum ethosu_error_codes ethosu_get_irq_history_mask(struct ethosu_device *dev, uint16_t *irq_history_mask);
+enum ethosu_error_codes ethosu_dev_get_irq_history_mask(struct ethosu_device *dev, uint16_t *irq_history_mask);
 
 /**
  * Clear the given bits in the
@@ -226,19 +227,19 @@ enum ethosu_error_codes ethosu_get_irq_history_mask(struct ethosu_device *dev, u
  *                                     clear in the IRQ history mask.
  * \return                             \ref ethosu_error_codes
  */
-enum ethosu_error_codes ethosu_clear_irq_history_mask(struct ethosu_device *dev, uint16_t irq_history_clear_mask);
+enum ethosu_error_codes ethosu_dev_clear_irq_history_mask(struct ethosu_device *dev, uint16_t irq_history_clear_mask);
 
 /**
  * Perform a NPU soft reset.
  * \return                     \ref ethosu_error_codes
  */
-enum ethosu_error_codes ethosu_soft_reset(struct ethosu_device *dev);
+enum ethosu_error_codes ethosu_dev_soft_reset(struct ethosu_device *dev);
 
 /**
  * Wait for reset ready.
  * \return                     \ref ethosu_error_codes
  */
-enum ethosu_error_codes ethosu_wait_for_reset(struct ethosu_device *dev);
+enum ethosu_error_codes ethosu_dev_wait_for_reset(struct ethosu_device *dev);
 
 /**
  * Read and return the content of a given NPU APB
@@ -250,10 +251,10 @@ enum ethosu_error_codes ethosu_wait_for_reset(struct ethosu_device *dev);
  *                             written.
  * \return                     \ref ethosu_error_codes
  */
-enum ethosu_error_codes ethosu_read_apb_reg(struct ethosu_device *dev,
-                                            uint32_t start_address,
-                                            uint16_t num_reg,
-                                            uint32_t *reg_p);
+enum ethosu_error_codes ethosu_dev_read_apb_reg(struct ethosu_device *dev,
+                                                uint32_t start_address,
+                                                uint16_t num_reg,
+                                                uint32_t *reg_p);
 
 /**
  * Set qconfig register. I.e.
@@ -262,7 +263,7 @@ enum ethosu_error_codes ethosu_read_apb_reg(struct ethosu_device *dev,
  *                             enum ethosu_memory_type.
  * \return                     \ref ethosu_error_codes
  */
-enum ethosu_error_codes ethosu_set_qconfig(struct ethosu_device *dev, enum ethosu_memory_type memory_type);
+enum ethosu_error_codes ethosu_dev_set_qconfig(struct ethosu_device *dev, enum ethosu_memory_type memory_type);
 
 /**
  * Set register REGIONCFG.
@@ -272,9 +273,9 @@ enum ethosu_error_codes ethosu_set_qconfig(struct ethosu_device *dev, enum ethos
  * \param[in] memory_type      Memory_type to use for region: enum ethosu_memory_type.
  * \return                     \ref ethosu_error_codes
  */
-enum ethosu_error_codes ethosu_set_regioncfg(struct ethosu_device *dev,
-                                             uint8_t region,
-                                             enum ethosu_memory_type memory_type);
+enum ethosu_error_codes ethosu_dev_set_regioncfg(struct ethosu_device *dev,
+                                                 uint8_t region,
+                                                 enum ethosu_memory_type memory_type);
 
 /**
  * Set AXI limit parameters for port 0 counter 0.
@@ -284,11 +285,11 @@ enum ethosu_error_codes ethosu_set_regioncfg(struct ethosu_device *dev,
  * \param[in] max_writes       Maximum number of outstanding writes.
  * \return                     \ref ethosu_error_codes
  */
-enum ethosu_error_codes ethosu_set_axi_limit0(struct ethosu_device *dev,
-                                              enum ethosu_axi_limit_beats max_beats,
-                                              enum ethosu_axi_limit_mem_type memtype,
-                                              uint8_t max_reads,
-                                              uint8_t max_writes);
+enum ethosu_error_codes ethosu_dev_set_axi_limit0(struct ethosu_device *dev,
+                                                  enum ethosu_axi_limit_beats max_beats,
+                                                  enum ethosu_axi_limit_mem_type memtype,
+                                                  uint8_t max_reads,
+                                                  uint8_t max_writes);
 /**
  * Set AXI limit parameters for port 0 counter 1.
  * \param[in] max_beats        Burst split alignment, \ref ethosu_axi_limit_beats.
@@ -297,11 +298,11 @@ enum ethosu_error_codes ethosu_set_axi_limit0(struct ethosu_device *dev,
  * \param[in] max_writes       Maximum number of outstanding writes.
  * \return                     \ref ethosu_error_codes
  */
-enum ethosu_error_codes ethosu_set_axi_limit1(struct ethosu_device *dev,
-                                              enum ethosu_axi_limit_beats max_beats,
-                                              enum ethosu_axi_limit_mem_type memtype,
-                                              uint8_t max_reads,
-                                              uint8_t max_writes);
+enum ethosu_error_codes ethosu_dev_set_axi_limit1(struct ethosu_device *dev,
+                                                  enum ethosu_axi_limit_beats max_beats,
+                                                  enum ethosu_axi_limit_mem_type memtype,
+                                                  uint8_t max_reads,
+                                                  uint8_t max_writes);
 /**
  * Set AXI limit parameters for port 1 counter 2.
  * \param[in] max_beats        Burst split alignment, \ref ethosu_axi_limit_beats.
@@ -310,11 +311,11 @@ enum ethosu_error_codes ethosu_set_axi_limit1(struct ethosu_device *dev,
  * \param[in] max_writes       Maximum number of outstanding writes.
  * \return                     \ref ethosu_error_codes
  */
-enum ethosu_error_codes ethosu_set_axi_limit2(struct ethosu_device *dev,
-                                              enum ethosu_axi_limit_beats max_beats,
-                                              enum ethosu_axi_limit_mem_type memtype,
-                                              uint8_t max_reads,
-                                              uint8_t max_writes);
+enum ethosu_error_codes ethosu_dev_set_axi_limit2(struct ethosu_device *dev,
+                                                  enum ethosu_axi_limit_beats max_beats,
+                                                  enum ethosu_axi_limit_mem_type memtype,
+                                                  uint8_t max_reads,
+                                                  uint8_t max_writes);
 /**
  * Set AXI limit parameters for port 1 counter 3.
  * \param[in] max_beats        Burst split alignment, \ref ethosu_axi_limit_beats.
@@ -323,25 +324,24 @@ enum ethosu_error_codes ethosu_set_axi_limit2(struct ethosu_device *dev,
  * \param[in] max_writes       Maximum number of outstanding writes.
  * \return                     \ref ethosu_error_codes
  */
-enum ethosu_error_codes ethosu_set_axi_limit3(struct ethosu_device *dev,
-                                              enum ethosu_axi_limit_beats max_beats,
-                                              enum ethosu_axi_limit_mem_type memtype,
-                                              uint8_t max_reads,
-                                              uint8_t max_writes);
+enum ethosu_error_codes ethosu_dev_set_axi_limit3(struct ethosu_device *dev,
+                                                  enum ethosu_axi_limit_beats max_beats,
+                                                  enum ethosu_axi_limit_mem_type memtype,
+                                                  uint8_t max_reads,
+                                                  uint8_t max_writes);
 
 /**
  * Get current command stream queue read position.
- * \param[out] qread           Pointer to queue read.
- * \return                     \ref ethosu_error_codes
+ * \return                     qread position
  */
-enum ethosu_error_codes ethosu_get_qread(struct ethosu_device *dev, uint32_t *qread);
+uint32_t ethosu_dev_get_qread(struct ethosu_device *dev);
 
 /**
  * Get revision of NPU
  * \param[out] revision        Pointer to revision read.
  * \return                     \ref ethosu_error_codes
  */
-enum ethosu_error_codes ethosu_get_revision(struct ethosu_device *dev, uint32_t *revision);
+enum ethosu_error_codes ethosu_dev_get_revision(struct ethosu_device *dev, uint32_t *revision);
 
 /**
  * Issue run command for the currently programmed
@@ -349,7 +349,7 @@ enum ethosu_error_codes ethosu_get_revision(struct ethosu_device *dev, uint32_t
  *                             position.
  * \return                     \ref ethosu_error_codes
  */
-enum ethosu_error_codes ethosu_set_command_run(struct ethosu_device *dev);
+enum ethosu_error_codes ethosu_dev_set_command_run(struct ethosu_device *dev);
 
 /**
  * Dump a 1KB section of SHRAM.
@@ -359,7 +359,7 @@ enum ethosu_error_codes ethosu_set_command_run(struct ethosu_device *dev);
  *                             written.
  * \return                     \ref ethosu_error_codes
  */
-enum ethosu_error_codes ethosu_get_shram_data(struct ethosu_device *dev, int section, uint32_t *shram_p);
+enum ethosu_error_codes ethosu_dev_get_shram_data(struct ethosu_device *dev, int section, uint32_t *shram_p);
 
 /**
  * Set clock and power q request enable bits.
@@ -367,30 +367,30 @@ enum ethosu_error_codes ethosu_get_shram_data(struct ethosu_device *dev, int sec
  * \param[in] power_q          Power q ENABLE/DISABLE \ref power_q_request.
  * \return                     \ref ethosu_error_codes
  */
-enum ethosu_error_codes ethosu_set_clock_and_power(struct ethosu_device *dev,
-                                                   enum ethosu_clock_q_request clock_q,
-                                                   enum ethosu_power_q_request power_q);
+enum ethosu_error_codes ethosu_dev_set_clock_and_power(struct ethosu_device *dev,
+                                                       enum ethosu_clock_q_request clock_q,
+                                                       enum ethosu_power_q_request power_q);
 
 /**
  * Read register.
  * \param[in] address          Address to read.
  * \return                     Register value.
  */
-uint32_t ethosu_read_reg(struct ethosu_device *dev, uint32_t address);
+uint32_t ethosu_dev_read_reg(struct ethosu_device *dev, uint32_t address);
 
 /**
  * Write register.
  * \param[in] address          Address to read.
  * \param[in] value            Value to be written.
  */
-void ethosu_write_reg(struct ethosu_device *dev, uint32_t address, uint32_t value);
+void ethosu_dev_write_reg(struct ethosu_device *dev, uint32_t address, uint32_t value);
 
 /**
  * Write register with shadow variable.
  * \param[in] address          Address to read.
  * \param[in] value            Value to be written.
  */
-void ethosu_write_reg_shadow(struct ethosu_device *dev, uint32_t address, uint32_t value, uint32_t *shadow);
+void ethosu_dev_write_reg_shadow(struct ethosu_device *dev, uint32_t address, uint32_t value, uint32_t *shadow);
 
 /**
  * Save the PMU configuration to ethosu_device struct.
@@ -398,7 +398,7 @@ void ethosu_write_reg_shadow(struct ethosu_device *dev, uint32_t address, uint32
  *                             saved.
  * \return                     \ref ethosu_error_codes
  */
-enum ethosu_error_codes ethosu_save_pmu_config(struct ethosu_device *dev);
+enum ethosu_error_codes ethosu_dev_save_pmu_config(struct ethosu_device *dev);
 
 /**
  * Restore the PMU configuration from a ethosu_device struct.
@@ -406,7 +406,7 @@ enum ethosu_error_codes ethosu_save_pmu_config(struct ethosu_device *dev);
  *                             stored.
  * \return                     \ref ethosu_error_codes
  */
-enum ethosu_error_codes ethosu_restore_pmu_config(struct ethosu_device *dev);
+enum ethosu_error_codes ethosu_dev_restore_pmu_config(struct ethosu_device *dev);
 
 /**
  * Save PMU counters to shadow variables in memory.
@@ -414,7 +414,15 @@ enum ethosu_error_codes ethosu_restore_pmu_config(struct ethosu_device *dev);
  *                             stored.
  * \return                     \ref ethosu_error_codes
  */
-enum ethosu_error_codes ethosu_save_pmu_counters(struct ethosu_device *dev);
+enum ethosu_error_codes ethosu_dev_save_pmu_counters(struct ethosu_device *dev);
+
+/**
+ * Check if the PROT register value has changed compared to cached value.
+ * \param[in] dev              Ethos-U device to check.
+ * \return                     true if register value differs from cached value,
+ *                             false otherwise.
+ */
+bool ethosu_dev_prot_has_changed(struct ethosu_device *dev);
 
 /**
  * Check if the STATUS register has any error bits set or not.
@@ -422,7 +430,7 @@ enum ethosu_error_codes ethosu_save_pmu_counters(struct ethosu_device *dev);
  * \return                     true if any error bits set,
  *                             false otherwise.
  */
-bool ethosu_status_has_error(struct ethosu_device *dev);
+bool ethosu_dev_status_has_error(struct ethosu_device *dev);
 
 #ifdef __cplusplus
 }
diff --git a/include/ethosu_driver.h b/include/ethosu_driver.h
index e492f91..30d707f 100644
--- a/include/ethosu_driver.h
+++ b/include/ethosu_driver.h
@@ -34,54 +34,44 @@ extern "C" {
 #endif
 
 /******************************************************************************
+ * Defines
+ ******************************************************************************/
+
+#define ETHOSU_DRIVER_VERSION_MAJOR 0  ///< Driver major version
+#define ETHOSU_DRIVER_VERSION_MINOR 16 ///< Driver minor version
+#define ETHOSU_DRIVER_VERSION_PATCH 0  ///< Driver patch version
+
+/******************************************************************************
  * Types
  ******************************************************************************/
 
 struct ethosu_driver
 {
     struct ethosu_device dev;
-    bool abort_inference;
+    struct ethosu_driver *next;
+    void *semaphore;
     uint64_t fast_memory;
     size_t fast_memory_size;
     bool status_error;
+    bool abort_inference;
     bool dev_power_always_on;
-    struct ethosu_driver *next;
     bool reserved;
     volatile bool irq_triggered;
-    void *semaphore;
     uint8_t clock_request;
     uint8_t power_request;
 };
 
-struct ethosu_version_id
+struct ethosu_driver_version
 {
-    // Ethos-U id
-    uint8_t version_status;
-    uint8_t version_minor;
-    uint8_t version_major;
-    uint8_t product_major;
-    uint8_t arch_patch_rev;
-    uint8_t arch_minor_rev;
-    uint8_t arch_major_rev;
-
-    // Driver Version
-    uint8_t driver_patch_rev;
-    uint8_t driver_minor_rev;
-    uint8_t driver_major_rev;
+    uint8_t major;
+    uint8_t minor;
+    uint8_t patch;
 };
 
-struct ethosu_version_config
+struct ethosu_hw_info
 {
-    uint8_t macs_per_cc;
-    uint8_t cmd_stream_version;
-    uint8_t shram_size;
-    uint8_t custom_dma;
-};
-
-struct ethosu_version
-{
-    struct ethosu_version_id id;
-    struct ethosu_version_config cfg;
+    struct ethosu_id version;
+    struct ethosu_config cfg;
 };
 
 enum ethosu_request_clients
@@ -91,10 +81,43 @@ enum ethosu_request_clients
 };
 
 /******************************************************************************
- * Variables
+ * Prototypes (weak functions in driver)
  ******************************************************************************/
 
-extern struct ethosu_driver ethosu_drv;
+/**
+ * Interrupt handler to be called on IRQ from Ethos-U
+ */
+void ethosu_irq_handler(struct ethosu_driver *drv);
+
+/*
+ * Flush/clean the data cache by address and size. Passing NULL as p argument
+ * expects the whole cache to be flushed.
+ */
+
+void ethosu_flush_dcache(uint32_t *p, size_t bytes);
+/*
+ * Invalidate the data cache by address and size. Passing NULL as p argument
+ * expects the whole cache to be invalidated.
+ */
+void ethosu_invalidate_dcache(uint32_t *p, size_t bytes);
+
+/*
+ * Minimal sempahore and mutex implementation for baremetal applications. See
+ * ethosu_driver.c.
+ */
+void *ethosu_mutex_create(void);
+void ethosu_mutex_lock(void *mutex);
+void ethosu_mutex_unlock(void *mutex);
+void *ethosu_semaphore_create(void);
+void ethosu_semaphore_take(void *sem);
+void ethosu_semaphore_give(void *sem);
+
+/*
+ * Callbacks for begin/end of inference. inference_data pointer is set in the
+ * ethosu_invoke() call, referenced as custom_data_ptr.
+ */
+void ethosu_inference_begin(struct ethosu_driver *drv, const void *inference_data);
+void ethosu_inference_end(struct ethosu_driver *drv, const void *inference_data);
 
 /******************************************************************************
  * Prototypes
@@ -111,9 +134,14 @@ int ethosu_init(struct ethosu_driver *drv,
                 uint32_t privilege_enable);
 
 /**
- * Get Ethos-U version.
+ * Get Ethos-U driver version.
+ */
+void ethosu_get_driver_version(struct ethosu_driver_version *ver);
+
+/**
+ * Get Ethos-U hardware information.
  */
-int ethosu_get_version(struct ethosu_driver *drv, struct ethosu_version *version);
+void ethosu_get_hw_info(struct ethosu_driver *drv, struct ethosu_hw_info *hw);
 
 /**
  * Invoke Vela command stream.
@@ -131,26 +159,11 @@ int ethosu_invoke(struct ethosu_driver *drv,
 void ethosu_abort(struct ethosu_driver *drv);
 
 /**
- * Interrupt handler do be called on IRQ from Ethos-U
- */
-void ethosu_irq_handler(struct ethosu_driver *drv);
-
-/**
  * Set Ethos-U power mode.
  */
 void ethosu_set_power_mode(struct ethosu_driver *drv, bool always_on);
 
 /**
- *  Register a driver for multiNPU usage
- */
-int ethosu_register_driver(struct ethosu_driver *drv);
-
-/**
- * Deregister a driver from multiNPU usage
- */
-int ethosu_deregister_driver(struct ethosu_driver *drv);
-
-/**
  * Reserves a driver to execute inference with
  */
 struct ethosu_driver *ethosu_reserve_driver(void);
diff --git a/src/ethosu_common.h b/src/ethosu_common.h
index bf3aff0..6342df2 100644
--- a/src/ethosu_common.h
+++ b/src/ethosu_common.h
@@ -23,104 +23,52 @@
  * Includes
  ******************************************************************************/
 
-#include "ethosu55_interface.h"
-
 #include <stdio.h>
+#include <string.h>
 
 /******************************************************************************
  * Defines
  ******************************************************************************/
 
+#define UNUSED(x) ((void)x)
+
+#define MASK_0_31_BITS (0xFFFFFFFF)
+#define MASK_32_47_BITS (0xFFFF00000000)
+
 // Log severity levels
-#define ETHOSU_LOG_EMERG 0
-#define ETHOSU_LOG_ALERT 1
-#define ETHOSU_LOG_CRIT 2
-#define ETHOSU_LOG_ERR 3
-#define ETHOSU_LOG_WARN 4
-#define ETHOSU_LOG_NOTICE 5
-#define ETHOSU_LOG_INFO 6
-#define ETHOSU_LOG_DEBUG 7
+#define ETHOSU_LOG_ERR 0
+#define ETHOSU_LOG_WARN 1
+#define ETHOSU_LOG_INFO 2
+#define ETHOSU_LOG_DEBUG 3
 
 // Define default log severity
 #ifndef ETHOSU_LOG_SEVERITY
 #define ETHOSU_LOG_SEVERITY ETHOSU_LOG_WARN
 #endif
 
-#if ETHOSU_LOG_SEVERITY >= ETHOSU_LOG_EMERG
-#define LOG_EMERG(format, ...)                                                                                         \
-    fprintf(stderr, format, ##__VA_ARGS__);                                                                            \
-    fflush(stderr);                                                                                                    \
-    exit(-1)
-#else
-#define LOG_EMERG(format, ...)
-#endif
-
-#if ETHOSU_LOG_SEVERITY >= ETHOSU_LOG_ALERT
-#define LOG_ALERT(format, ...)                                                                                         \
-    fprintf(stderr, format, ##__VA_ARGS__);                                                                            \
-    fflush(stderr);                                                                                                    \
-    exit(-1)
-#else
-#define LOG_ALERT(format, ...)
-#endif
-
-#if ETHOSU_LOG_SEVERITY >= ETHOSU_LOG_CRIT
-#define LOG_CRIT(format, ...)                                                                                          \
-    fprintf(stderr, format, ##__VA_ARGS__);                                                                            \
-    fflush(stderr);                                                                                                    \
-    exit(-1)
-#else
-#define LOG_CRIT(format, ...)
-#endif
-
+// Log formatting
 #if ETHOSU_LOG_SEVERITY >= ETHOSU_LOG_ERR
-#define LOG_ERR(format, ...)                                                                                           \
-    fprintf(stderr, format, ##__VA_ARGS__);                                                                            \
-    fflush(stderr)
+#define LOG_ERR(f, ...) fprintf(stderr, "E: " f " (%s:%d)\n", ##__VA_ARGS__, strrchr("/" __FILE__, '/') + 1, __LINE__)
 #else
-#define LOG_ERR(format, ...)
+#define LOG_ERR(f, ...)
 #endif
 
 #if ETHOSU_LOG_SEVERITY >= ETHOSU_LOG_WARN
-#define LOG_WARN(format, ...) fprintf(stdout, format, ##__VA_ARGS__)
+#define LOG_WARN(f, ...) fprintf(stdout, "W: " f "\n", ##__VA_ARGS__)
 #else
-#define LOG_WARN(format, ...)
-#endif
-
-#if ETHOSU_LOG_SEVERITY >= ETHOSU_LOG_NOTICE
-#define LOG_NOTICE(format, ...) fprintf(stdout, format, ##__VA_ARGS__)
-#else
-#define LOG_NOTICE(format, ...)
+#define LOG_WARN(f, ...)
 #endif
 
 #if ETHOSU_LOG_SEVERITY >= ETHOSU_LOG_INFO
-#define LOG_INFO(format, ...) fprintf(stdout, format, ##__VA_ARGS__)
+#define LOG_INFO(f, ...) fprintf(stdout, "I: " f "\n", ##__VA_ARGS__)
 #else
-#define LOG_INFO(format, ...)
+#define LOG_INFO(f, ...)
 #endif
 
 #if ETHOSU_LOG_SEVERITY >= ETHOSU_LOG_DEBUG
-#define LOG_DEBUG(format, ...) fprintf(stdout, format, ##__VA_ARGS__)
+#define LOG_DEBUG(f, ...) fprintf(stdout, "D: %s(): " f "\n", __FUNCTION__, ##__VA_ARGS__)
 #else
-#define LOG_DEBUG(format, ...)
+#define LOG_DEBUG(f, ...)
 #endif
 
-#define UNUSED(x) ((void)x)
-
-#define VER_STR(X) VNUM_STR(X)
-#define VNUM_STR(X) #X
-
-#define MASK_0_31_BITS (0xFFFFFFFF)
-#define MASK_32_47_BITS (0xFFFF00000000)
-
-/******************************************************************************
- * Inline functions
- ******************************************************************************/
-
-static const __attribute__((section("npu_driver_version"))) char driver_version_str[] = VER_STR(
-    ETHOSU_DRIVER_VERSION_MAJOR) "." VER_STR(ETHOSU_DRIVER_VERSION_MINOR) "." VER_STR(ETHOSU_DRIVER_VERSION_PATCH);
-
-static const __attribute__((section("npu_driver_arch_version"))) char driver_arch_version_str[] =
-    VER_STR(NNX_ARCH_VERSION_MAJOR) "." VER_STR(NNX_ARCH_VERSION_MINOR) "." VER_STR(NNX_ARCH_VERSION_PATCH);
-
 #endif // ETHOSU_COMMON_H
diff --git a/src/ethosu_device.c b/src/ethosu_device.c
deleted file mode 100644
index e8d067f..0000000
--- a/src/ethosu_device.c
+++ /dev/null
@@ -1,686 +0,0 @@
-/*
- * Copyright (c) 2019-2021 Arm Limited. All rights reserved.
- *
- * SPDX-License-Identifier: Apache-2.0
- *
- * Licensed under the Apache License, Version 2.0 (the License); you may
- * not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an AS IS BASIS, WITHOUT
- * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-#include "ethosu_device.h"
-#include "ethosu_common.h"
-#include "ethosu_config.h"
-
-#include <assert.h>
-#include <stddef.h>
-#include <stdio.h>
-
-#define BASEP_OFFSET 4
-#define REG_OFFSET 4
-#define BYTES_1KB 1024
-
-#define ADDRESS_BITS 48
-#define ADDRESS_MASK ((1ull << ADDRESS_BITS) - 1)
-
-#if defined(ARM_NPU_STUB)
-static uint32_t stream_length = 0;
-#endif
-
-enum ethosu_error_codes ethosu_dev_init(struct ethosu_device *dev,
-                                        const void *base_address,
-                                        uint32_t secure_enable,
-                                        uint32_t privilege_enable)
-{
-#if !defined(ARM_NPU_STUB)
-    dev->base_address = (volatile uintptr_t)base_address;
-    dev->secure       = secure_enable;
-    dev->privileged   = privilege_enable;
-
-    ethosu_save_pmu_config(dev);
-#else
-    UNUSED(dev);
-    UNUSED(base_address);
-#endif
-    return ETHOSU_SUCCESS;
-}
-
-enum ethosu_error_codes ethosu_get_id(struct ethosu_device *dev, struct ethosu_id *id)
-{
-    struct id_r _id;
-
-#if !defined(ARM_NPU_STUB)
-    _id.word = ethosu_read_reg(dev, NPU_REG_ID);
-#else
-    UNUSED(dev);
-
-    _id.word           = 0;
-    _id.arch_patch_rev = NNX_ARCH_VERSION_PATCH;
-    _id.arch_minor_rev = NNX_ARCH_VERSION_MINOR;
-    _id.arch_major_rev = NNX_ARCH_VERSION_MAJOR;
-#endif
-
-    id->version_status = _id.version_status;
-    id->version_minor  = _id.version_minor;
-    id->version_major  = _id.version_major;
-    id->product_major  = _id.product_major;
-    id->arch_patch_rev = _id.arch_patch_rev;
-    id->arch_minor_rev = _id.arch_minor_rev;
-    id->arch_major_rev = _id.arch_major_rev;
-
-    return ETHOSU_SUCCESS;
-}
-
-enum ethosu_error_codes ethosu_get_config(struct ethosu_device *dev, struct ethosu_config *config)
-{
-    struct config_r cfg = {.word = 0};
-
-#if !defined(ARM_NPU_STUB)
-    cfg.word = ethosu_read_reg(dev, NPU_REG_CONFIG);
-#else
-    UNUSED(dev);
-#endif
-
-    config->macs_per_cc        = cfg.macs_per_cc;
-    config->cmd_stream_version = cfg.cmd_stream_version;
-    config->shram_size         = cfg.shram_size;
-    config->custom_dma         = cfg.custom_dma;
-
-    return ETHOSU_SUCCESS;
-}
-
-enum ethosu_error_codes ethosu_run_command_stream(struct ethosu_device *dev,
-                                                  const uint8_t *cmd_stream_ptr,
-                                                  uint32_t cms_length,
-                                                  const uint64_t *base_addr,
-                                                  int num_base_addr)
-{
-    enum ethosu_error_codes ret_code = ETHOSU_SUCCESS;
-
-#if !defined(ARM_NPU_STUB)
-    assert(num_base_addr <= ETHOSU_DRIVER_BASEP_INDEXES);
-
-    uint64_t qbase = (uintptr_t)cmd_stream_ptr + BASE_POINTER_OFFSET;
-    assert(qbase <= ADDRESS_MASK);
-    LOG_DEBUG("QBASE=0x%016llx, QSIZE=%u, base_pointer_offset=0x%08x\n", qbase, cms_length, BASE_POINTER_OFFSET);
-    ethosu_write_reg(dev, NPU_REG_QBASE0, qbase & 0xffffffff);
-    ethosu_write_reg(dev, NPU_REG_QBASE1, qbase >> 32);
-    ethosu_write_reg(dev, NPU_REG_QSIZE, cms_length);
-
-    for (int i = 0; i < num_base_addr; i++)
-    {
-        uint64_t addr = base_addr[i] + BASE_POINTER_OFFSET;
-        assert(addr <= ADDRESS_MASK);
-        LOG_DEBUG("BASEP%d=0x%016llx\n", i, addr);
-        ethosu_write_reg(dev, NPU_REG_BASEP0 + (2 * i) * BASEP_OFFSET, addr & 0xffffffff);
-        ethosu_write_reg(dev, NPU_REG_BASEP0 + (2 * i + 1) * BASEP_OFFSET, addr >> 32);
-    }
-
-    ret_code = ethosu_set_command_run(dev);
-#else
-    // NPU stubbed
-    UNUSED(dev);
-    stream_length = cms_length;
-    UNUSED(cmd_stream_ptr);
-    UNUSED(base_addr);
-    assert(num_base_addr < ETHOSU_DRIVER_BASEP_INDEXES);
-#if defined(NDEBUG)
-    UNUSED(num_base_addr);
-#endif
-#endif
-
-    return ret_code;
-}
-
-enum ethosu_error_codes ethosu_is_irq_raised(struct ethosu_device *dev, uint8_t *irq_raised)
-{
-#if !defined(ARM_NPU_STUB)
-    struct status_r status;
-    status.word = ethosu_read_reg(dev, NPU_REG_STATUS);
-    if (status.irq_raised == 1)
-    {
-        *irq_raised = 1;
-    }
-    else
-    {
-        *irq_raised = 0;
-    }
-#else
-    UNUSED(dev);
-    *irq_raised = 1;
-#endif
-    return ETHOSU_SUCCESS;
-}
-
-enum ethosu_error_codes ethosu_clear_irq_status(struct ethosu_device *dev)
-{
-#if !defined(ARM_NPU_STUB)
-    struct cmd_r oldcmd;
-    oldcmd.word = ethosu_read_reg(dev, NPU_REG_CMD);
-    struct cmd_r cmd;
-
-    cmd.word           = 0;
-    cmd.clear_irq      = 1;
-    cmd.clock_q_enable = oldcmd.clock_q_enable;
-    cmd.power_q_enable = oldcmd.power_q_enable;
-    ethosu_write_reg(dev, NPU_REG_CMD, cmd.word);
-    LOG_DEBUG("CMD=0x%08x\n", cmd.word);
-#else
-    UNUSED(dev);
-#endif
-    return ETHOSU_SUCCESS;
-}
-
-enum ethosu_error_codes ethosu_soft_reset(struct ethosu_device *dev)
-{
-    enum ethosu_error_codes return_code = ETHOSU_SUCCESS;
-#if !defined(ARM_NPU_STUB)
-    struct reset_r reset;
-    struct prot_r prot;
-
-    reset.word        = 0;
-    reset.pending_CPL = dev->privileged ? PRIVILEGE_LEVEL_PRIVILEGED : PRIVILEGE_LEVEL_USER;
-    reset.pending_CSL = dev->secure ? SECURITY_LEVEL_SECURE : SECURITY_LEVEL_NON_SECURE;
-
-    // Reset and set security level
-    LOG_INFO("Soft reset NPU\n");
-    ethosu_write_reg(dev, NPU_REG_RESET, reset.word);
-
-    // Wait for reset to complete
-    return_code = ethosu_wait_for_reset(dev);
-    if (return_code != ETHOSU_SUCCESS)
-    {
-        LOG_ERR("Soft reset timed out\n");
-        return return_code;
-    }
-
-    // Verify that NPU has switched security state and privilege level
-    prot.word = ethosu_read_reg(dev, NPU_REG_PROT);
-    if (prot.active_CPL != reset.pending_CPL || prot.active_CSL != reset.pending_CSL)
-    {
-        LOG_ERR("Failed to switch security state and privilege level\n");
-        // Register access not permitted
-        return ETHOSU_GENERIC_FAILURE;
-    }
-
-    // Save the prot register
-    dev->proto = ethosu_read_reg(dev, NPU_REG_PROT);
-
-    // Soft reset will clear the PMU configuration and counters. The shadow PMU counters
-    // are cleared by saving the PMU counters to ram, which will read back zeros.
-    // The PMU configuration will be restored in the invoke function after power save
-    // has been disabled.
-    ethosu_save_pmu_counters(dev);
-#else
-    UNUSED(dev);
-#endif
-
-    return return_code;
-}
-
-enum ethosu_error_codes ethosu_wait_for_reset(struct ethosu_device *dev)
-{
-#if !defined(ARM_NPU_STUB)
-    struct status_r status;
-
-    // Wait until reset status indicates that reset has been completed
-    for (int i = 0; i < 100000; i++)
-    {
-        status.word = ethosu_read_reg(dev, NPU_REG_STATUS);
-        if (0 == status.reset_status)
-        {
-            break;
-        }
-    }
-
-    if (1 == status.reset_status)
-    {
-        return ETHOSU_GENERIC_FAILURE;
-    }
-#else
-    UNUSED(dev);
-#endif
-
-    return ETHOSU_SUCCESS;
-}
-
-enum ethosu_error_codes ethosu_read_apb_reg(struct ethosu_device *dev,
-                                            uint32_t start_address,
-                                            uint16_t num_reg,
-                                            uint32_t *reg)
-{
-#if !defined(ARM_NPU_STUB)
-    uint32_t address = start_address;
-
-    assert((start_address + num_reg) < ID_REGISTERS_SIZE);
-
-    for (int i = 0; i < num_reg; i++)
-    {
-        reg[i] = ethosu_read_reg(dev, address);
-        address += REG_OFFSET;
-    }
-#else
-    // NPU stubbed
-    UNUSED(dev);
-    UNUSED(start_address);
-    UNUSED(num_reg);
-    UNUSED(reg);
-#endif
-
-    return ETHOSU_SUCCESS;
-}
-
-enum ethosu_error_codes ethosu_set_qconfig(struct ethosu_device *dev, enum ethosu_memory_type memory_type)
-{
-    if (memory_type > ETHOSU_AXI1_OUTSTANDING_COUNTER3)
-    {
-        return ETHOSU_INVALID_PARAM;
-    }
-#if !defined(ARM_NPU_STUB)
-    ethosu_write_reg(dev, NPU_REG_QCONFIG, memory_type);
-    LOG_DEBUG("QCONFIG=0x%08x\n", memory_type);
-#else
-    // NPU stubbed
-    UNUSED(dev);
-    UNUSED(memory_type);
-#endif
-    return ETHOSU_SUCCESS;
-}
-
-enum ethosu_error_codes ethosu_set_regioncfg(struct ethosu_device *dev,
-                                             uint8_t region,
-                                             enum ethosu_memory_type memory_type)
-{
-    if (region > 7)
-    {
-        return ETHOSU_INVALID_PARAM;
-    }
-#if !defined(ARM_NPU_STUB)
-    struct regioncfg_r regioncfg;
-    regioncfg.word = ethosu_read_reg(dev, NPU_REG_REGIONCFG);
-    regioncfg.word &= ~(0x3 << (2 * region));
-    regioncfg.word |= (memory_type & 0x3) << (2 * region);
-    ethosu_write_reg(dev, NPU_REG_REGIONCFG, regioncfg.word);
-    LOG_DEBUG("REGIONCFG%u=0x%08x\n", region, regioncfg.word);
-#else
-    // NPU stubbed
-    UNUSED(dev);
-    UNUSED(region);
-    UNUSED(memory_type);
-#endif
-    return ETHOSU_SUCCESS;
-}
-
-enum ethosu_error_codes ethosu_set_axi_limit0(struct ethosu_device *dev,
-                                              enum ethosu_axi_limit_beats max_beats,
-                                              enum ethosu_axi_limit_mem_type memtype,
-                                              uint8_t max_reads,
-                                              uint8_t max_writes)
-{
-#if !defined(ARM_NPU_STUB)
-    struct axi_limit0_r axi_limit0;
-    axi_limit0.word                     = 0;
-    axi_limit0.max_beats                = max_beats;
-    axi_limit0.memtype                  = memtype;
-    axi_limit0.max_outstanding_read_m1  = max_reads - 1;
-    axi_limit0.max_outstanding_write_m1 = max_writes - 1;
-
-    ethosu_write_reg(dev, NPU_REG_AXI_LIMIT0, axi_limit0.word);
-    LOG_DEBUG("AXI_LIMIT0=0x%08x\n", axi_limit0.word);
-#else
-    // NPU stubbed
-    UNUSED(dev);
-    UNUSED(max_beats);
-    UNUSED(memtype);
-    UNUSED(max_reads);
-    UNUSED(max_writes);
-#endif
-
-    return ETHOSU_SUCCESS;
-}
-
-enum ethosu_error_codes ethosu_set_axi_limit1(struct ethosu_device *dev,
-                                              enum ethosu_axi_limit_beats max_beats,
-                                              enum ethosu_axi_limit_mem_type memtype,
-                                              uint8_t max_reads,
-                                              uint8_t max_writes)
-{
-#if !defined(ARM_NPU_STUB)
-    struct axi_limit1_r axi_limit1;
-    axi_limit1.word                     = 0;
-    axi_limit1.max_beats                = max_beats;
-    axi_limit1.memtype                  = memtype;
-    axi_limit1.max_outstanding_read_m1  = max_reads - 1;
-    axi_limit1.max_outstanding_write_m1 = max_writes - 1;
-
-    ethosu_write_reg(dev, NPU_REG_AXI_LIMIT1, axi_limit1.word);
-    LOG_DEBUG("AXI_LIMIT1=0x%08x\n", axi_limit1.word);
-#else
-    // NPU stubbed
-    UNUSED(dev);
-    UNUSED(max_beats);
-    UNUSED(memtype);
-    UNUSED(max_reads);
-    UNUSED(max_writes);
-#endif
-
-    return ETHOSU_SUCCESS;
-}
-
-enum ethosu_error_codes ethosu_set_axi_limit2(struct ethosu_device *dev,
-                                              enum ethosu_axi_limit_beats max_beats,
-                                              enum ethosu_axi_limit_mem_type memtype,
-                                              uint8_t max_reads,
-                                              uint8_t max_writes)
-{
-#if !defined(ARM_NPU_STUB)
-    struct axi_limit2_r axi_limit2;
-    axi_limit2.word                     = 0;
-    axi_limit2.max_beats                = max_beats;
-    axi_limit2.memtype                  = memtype;
-    axi_limit2.max_outstanding_read_m1  = max_reads - 1;
-    axi_limit2.max_outstanding_write_m1 = max_writes - 1;
-
-    ethosu_write_reg(dev, NPU_REG_AXI_LIMIT2, axi_limit2.word);
-    LOG_DEBUG("AXI_LIMIT2=0x%08x\n", axi_limit2.word);
-#else
-    // NPU stubbed
-    UNUSED(dev);
-    UNUSED(max_beats);
-    UNUSED(memtype);
-    UNUSED(max_reads);
-    UNUSED(max_writes);
-#endif
-
-    return ETHOSU_SUCCESS;
-}
-
-enum ethosu_error_codes ethosu_set_axi_limit3(struct ethosu_device *dev,
-                                              enum ethosu_axi_limit_beats max_beats,
-                                              enum ethosu_axi_limit_mem_type memtype,
-                                              uint8_t max_reads,
-                                              uint8_t max_writes)
-{
-#if !defined(ARM_NPU_STUB)
-    struct axi_limit3_r axi_limit3;
-    axi_limit3.word                     = 0;
-    axi_limit3.max_beats                = max_beats;
-    axi_limit3.memtype                  = memtype;
-    axi_limit3.max_outstanding_read_m1  = max_reads - 1;
-    axi_limit3.max_outstanding_write_m1 = max_writes - 1;
-
-    ethosu_write_reg(dev, NPU_REG_AXI_LIMIT3, axi_limit3.word);
-    LOG_DEBUG("AXI_LIMIT3=0x%08x\n", axi_limit3.word);
-#else
-    // NPU stubbed
-    UNUSED(dev);
-    UNUSED(max_beats);
-    UNUSED(memtype);
-    UNUSED(max_reads);
-    UNUSED(max_writes);
-#endif
-
-    return ETHOSU_SUCCESS;
-}
-
-enum ethosu_error_codes ethosu_get_revision(struct ethosu_device *dev, uint32_t *revision)
-{
-#if !defined(ARM_NPU_STUB)
-    *revision = ethosu_read_reg(dev, NPU_REG_REVISION);
-#else
-    UNUSED(dev);
-    *revision = 0xDEADC0DE;
-#endif
-    return ETHOSU_SUCCESS;
-}
-
-enum ethosu_error_codes ethosu_get_qread(struct ethosu_device *dev, uint32_t *qread)
-{
-#if !defined(ARM_NPU_STUB)
-    *qread = ethosu_read_reg(dev, NPU_REG_QREAD);
-#else
-    UNUSED(dev);
-    *qread = stream_length;
-#endif
-    return ETHOSU_SUCCESS;
-}
-
-enum ethosu_error_codes ethosu_get_status_mask(struct ethosu_device *dev, uint16_t *status_mask)
-{
-#if !defined(ARM_NPU_STUB)
-    struct status_r status;
-
-    status.word  = ethosu_read_reg(dev, NPU_REG_STATUS);
-    *status_mask = status.word & 0xFFFF;
-#else
-    UNUSED(dev);
-    *status_mask = 0x0000;
-#endif
-    return ETHOSU_SUCCESS;
-}
-
-enum ethosu_error_codes ethosu_get_irq_history_mask(struct ethosu_device *dev, uint16_t *irq_history_mask)
-{
-#if !defined(ARM_NPU_STUB)
-    struct status_r status;
-
-    status.word       = ethosu_read_reg(dev, NPU_REG_STATUS);
-    *irq_history_mask = status.irq_history_mask;
-#else
-    UNUSED(dev);
-    *irq_history_mask = 0xffff;
-#endif
-    return ETHOSU_SUCCESS;
-}
-
-enum ethosu_error_codes ethosu_clear_irq_history_mask(struct ethosu_device *dev, uint16_t irq_history_clear_mask)
-{
-#if !defined(ARM_NPU_STUB)
-    struct cmd_r oldcmd;
-    oldcmd.word = ethosu_read_reg(dev, NPU_REG_CMD);
-
-    struct cmd_r cmd;
-    cmd.word              = 0;
-    cmd.clock_q_enable    = oldcmd.clock_q_enable;
-    cmd.power_q_enable    = oldcmd.power_q_enable;
-    cmd.clear_irq_history = irq_history_clear_mask;
-    ethosu_write_reg(dev, NPU_REG_CMD, cmd.word);
-    LOG_DEBUG("CMD=0x%08x\n", cmd.word);
-#else
-    UNUSED(dev);
-    UNUSED(irq_history_clear_mask);
-#endif
-    return ETHOSU_SUCCESS;
-}
-
-enum ethosu_error_codes ethosu_set_command_run(struct ethosu_device *dev)
-{
-#if !defined(ARM_NPU_STUB)
-    struct cmd_r oldcmd;
-    oldcmd.word = ethosu_read_reg(dev, NPU_REG_CMD);
-
-    struct cmd_r cmd;
-    cmd.word                        = 0;
-    cmd.transition_to_running_state = 1;
-    cmd.clock_q_enable              = oldcmd.clock_q_enable;
-    cmd.power_q_enable              = oldcmd.power_q_enable;
-    ethosu_write_reg(dev, NPU_REG_CMD, cmd.word);
-    LOG_DEBUG("CMD=0x%08x\n", cmd.word);
-#else
-    UNUSED(dev);
-#endif
-    return ETHOSU_SUCCESS;
-}
-
-enum ethosu_error_codes ethosu_get_shram_data(struct ethosu_device *dev, int section, uint32_t *shram_p)
-{
-#if !defined(ARM_NPU_STUB)
-    int i            = 0;
-    uint32_t address = NPU_REG_SHARED_BUFFER0;
-    ethosu_write_reg(dev, NPU_REG_DEBUG_ADDRESS, section * BYTES_1KB);
-
-    while (address <= NPU_REG_SHARED_BUFFER255)
-    {
-        shram_p[i] = ethosu_read_reg(dev, address);
-        address += REG_OFFSET;
-        i++;
-    }
-#else
-    // NPU stubbed
-    UNUSED(dev);
-    UNUSED(section);
-    UNUSED(shram_p);
-#endif
-
-    return ETHOSU_SUCCESS;
-}
-
-enum ethosu_error_codes ethosu_set_clock_and_power(struct ethosu_device *dev,
-                                                   enum ethosu_clock_q_request clock_q,
-                                                   enum ethosu_power_q_request power_q)
-{
-#if !defined(ARM_NPU_STUB)
-    struct cmd_r cmd;
-    cmd.word           = 0;
-    cmd.clock_q_enable = clock_q;
-    cmd.power_q_enable = power_q;
-    ethosu_write_reg(dev, NPU_REG_CMD, cmd.word);
-    LOG_DEBUG("CMD=0x%08x\n", cmd.word);
-#else
-    UNUSED(dev);
-    UNUSED(clock_q);
-    UNUSED(power_q);
-#endif
-    return ETHOSU_SUCCESS;
-}
-
-uint32_t ethosu_read_reg(struct ethosu_device *dev, uint32_t address)
-{
-#if !defined(ARM_NPU_STUB)
-    assert(dev->base_address != 0);
-    assert(address % 4 == 0);
-
-    volatile uint32_t *reg = (volatile uint32_t *)(dev->base_address + address);
-    return *reg;
-#else
-    UNUSED(dev);
-    UNUSED(address);
-
-    return 0;
-#endif
-}
-
-void ethosu_write_reg(struct ethosu_device *dev, uint32_t address, uint32_t value)
-{
-#if !defined(ARM_NPU_STUB)
-    assert(dev->base_address != 0);
-    assert(address % 4 == 0);
-
-    volatile uint32_t *reg = (volatile uint32_t *)(dev->base_address + address);
-    *reg                   = value;
-#else
-    UNUSED(dev);
-    UNUSED(address);
-    UNUSED(value);
-#endif
-}
-
-void ethosu_write_reg_shadow(struct ethosu_device *dev, uint32_t address, uint32_t value, uint32_t *shadow)
-{
-    ethosu_write_reg(dev, address, value);
-    *shadow = ethosu_read_reg(dev, address);
-}
-
-enum ethosu_error_codes ethosu_save_pmu_config(struct ethosu_device *dev)
-{
-#if !defined(ARM_NPU_STUB)
-    // Save the PMU control register
-    dev->pmcr = ethosu_read_reg(dev, NPU_REG_PMCR);
-
-    // Save IRQ control
-    dev->pmint = ethosu_read_reg(dev, NPU_REG_PMINTSET);
-
-    // Save the enabled events mask
-    dev->pmcnten = ethosu_read_reg(dev, NPU_REG_PMCNTENSET);
-
-    // Save start and stop event
-    dev->pmccntr_cfg = ethosu_read_reg(dev, NPU_REG_PMCCNTR_CFG);
-
-    // Save the event settings and counters
-    for (uint32_t i = 0; i < ETHOSU_PMU_NCOUNTERS; i++)
-    {
-        dev->pmu_evtypr[i] = ethosu_read_reg(dev, NPU_REG_PMEVTYPER0 + i * sizeof(uint32_t));
-    }
-#else
-    UNUSED(dev);
-#endif
-
-    return ETHOSU_SUCCESS;
-}
-
-enum ethosu_error_codes ethosu_restore_pmu_config(struct ethosu_device *dev)
-{
-#if !defined(ARM_NPU_STUB)
-    // Restore PMU control register
-    ethosu_write_reg(dev, NPU_REG_PMCR, dev->pmcr);
-
-    // Restore IRQ control
-    ethosu_write_reg(dev, NPU_REG_PMINTSET, dev->pmint);
-
-    // Restore enabled event mask
-    ethosu_write_reg(dev, NPU_REG_PMCNTENSET, dev->pmcnten);
-
-    // Restore start and stop event
-    ethosu_write_reg(dev, NPU_REG_PMCCNTR_CFG, dev->pmccntr_cfg);
-
-    // Save the event settings and counters
-    for (uint32_t i = 0; i < ETHOSU_PMU_NCOUNTERS; i++)
-    {
-        ethosu_write_reg(dev, NPU_REG_PMEVTYPER0 + i * sizeof(uint32_t), dev->pmu_evtypr[i]);
-    }
-#else
-    UNUSED(dev);
-#endif
-
-    return ETHOSU_SUCCESS;
-}
-
-enum ethosu_error_codes ethosu_save_pmu_counters(struct ethosu_device *dev)
-{
-#if !defined(ARM_NPU_STUB)
-    // Save the cycle counter
-    dev->pmccntr[0] = ethosu_read_reg(dev, NPU_REG_PMCCNTR_LO);
-    dev->pmccntr[1] = ethosu_read_reg(dev, NPU_REG_PMCCNTR_HI);
-
-    // Save the event settings and counters
-    for (uint32_t i = 0; i < ETHOSU_PMU_NCOUNTERS; i++)
-    {
-        dev->pmu_evcntr[i] = ethosu_read_reg(dev, NPU_REG_PMEVCNTR0 + i * sizeof(uint32_t));
-    }
-#else
-    UNUSED(dev);
-#endif
-
-    return ETHOSU_SUCCESS;
-}
-
-bool ethosu_status_has_error(struct ethosu_device *dev)
-{
-    bool status_error = false;
-#if !defined(ARM_NPU_STUB)
-    struct status_r status;
-    status.word  = ethosu_read_reg(dev, NPU_REG_STATUS);
-    status_error = ((1 == status.bus_status) || (1 == status.cmd_parse_error) || (1 == status.wd_fault) ||
-                    (1 == status.ecc_fault));
-#else
-    UNUSED(dev);
-#endif
-    return status_error;
-}
diff --git a/src/ethosu_device_u55.c b/src/ethosu_device_u55.c
new file mode 100644
index 0000000..24d0680
--- /dev/null
+++ b/src/ethosu_device_u55.c
@@ -0,0 +1,548 @@
+/*
+ * Copyright (c) 2019-2021 Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the License); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an AS IS BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include "ethosu55_interface.h"
+
+#include "ethosu_common.h"
+#include "ethosu_config.h"
+#include "ethosu_device.h"
+
+#include <assert.h>
+#include <stddef.h>
+#include <stdio.h>
+
+#define BASEP_OFFSET 4
+#define REG_OFFSET 4
+#define BYTES_1KB 1024
+
+#define ADDRESS_BITS 48
+#define ADDRESS_MASK ((1ull << ADDRESS_BITS) - 1)
+
+enum ethosu_error_codes ethosu_dev_init(struct ethosu_device *dev,
+                                        const void *base_address,
+                                        uint32_t secure_enable,
+                                        uint32_t privilege_enable)
+{
+    dev->base_address = (volatile uintptr_t)base_address;
+    dev->secure       = secure_enable;
+    dev->privileged   = privilege_enable;
+
+    ethosu_dev_save_pmu_config(dev);
+
+    return ETHOSU_SUCCESS;
+}
+
+enum ethosu_error_codes ethosu_dev_get_id(struct ethosu_device *dev, struct ethosu_id *id)
+{
+    struct id_r _id;
+
+    _id.word = ethosu_dev_read_reg(dev, NPU_REG_ID);
+
+    id->version_status = _id.version_status;
+    id->version_minor  = _id.version_minor;
+    id->version_major  = _id.version_major;
+    id->product_major  = _id.product_major;
+    id->arch_patch_rev = _id.arch_patch_rev;
+    id->arch_minor_rev = _id.arch_minor_rev;
+    id->arch_major_rev = _id.arch_major_rev;
+
+    return ETHOSU_SUCCESS;
+}
+
+enum ethosu_error_codes ethosu_dev_get_config(struct ethosu_device *dev, struct ethosu_config *config)
+{
+    struct config_r cfg = {.word = 0};
+
+    cfg.word = ethosu_dev_read_reg(dev, NPU_REG_CONFIG);
+
+    config->macs_per_cc        = cfg.macs_per_cc;
+    config->cmd_stream_version = cfg.cmd_stream_version;
+    config->shram_size         = cfg.shram_size;
+    config->custom_dma         = cfg.custom_dma;
+
+    return ETHOSU_SUCCESS;
+}
+
+enum ethosu_error_codes ethosu_dev_run_command_stream(struct ethosu_device *dev,
+                                                      const uint8_t *cmd_stream_ptr,
+                                                      uint32_t cms_length,
+                                                      const uint64_t *base_addr,
+                                                      int num_base_addr)
+{
+    assert(num_base_addr <= ETHOSU_BASEP_INDEXES);
+
+    uint64_t qbase = (uintptr_t)cmd_stream_ptr + BASE_POINTER_OFFSET;
+    assert(qbase <= ADDRESS_MASK);
+    LOG_DEBUG("QBASE=0x%016llx, QSIZE=%u, base_pointer_offset=0x%08x\n", qbase, cms_length, BASE_POINTER_OFFSET);
+
+    ethosu_dev_write_reg(dev, NPU_REG_QBASE0, qbase & 0xffffffff);
+    ethosu_dev_write_reg(dev, NPU_REG_QBASE1, qbase >> 32);
+    ethosu_dev_write_reg(dev, NPU_REG_QSIZE, cms_length);
+
+    for (int i = 0; i < num_base_addr; i++)
+    {
+        uint64_t addr = base_addr[i] + BASE_POINTER_OFFSET;
+        assert(addr <= ADDRESS_MASK);
+        LOG_DEBUG("BASEP%d=0x%016llx\n", i, addr);
+        ethosu_dev_write_reg(dev, NPU_REG_BASEP0 + (2 * i) * BASEP_OFFSET, addr & 0xffffffff);
+        ethosu_dev_write_reg(dev, NPU_REG_BASEP0 + (2 * i + 1) * BASEP_OFFSET, addr >> 32);
+    }
+
+    return ethosu_dev_set_command_run(dev);
+}
+
+enum ethosu_error_codes ethosu_dev_is_irq_raised(struct ethosu_device *dev, uint8_t *irq_raised)
+{
+    struct status_r status;
+
+    status.word = ethosu_dev_read_reg(dev, NPU_REG_STATUS);
+
+    if (status.irq_raised == 1)
+    {
+        *irq_raised = 1;
+    }
+    else
+    {
+        *irq_raised = 0;
+    }
+
+    return ETHOSU_SUCCESS;
+}
+
+enum ethosu_error_codes ethosu_dev_clear_irq_status(struct ethosu_device *dev)
+{
+    struct cmd_r oldcmd;
+    struct cmd_r cmd;
+
+    oldcmd.word = ethosu_dev_read_reg(dev, NPU_REG_CMD);
+
+    cmd.word           = 0;
+    cmd.clear_irq      = 1;
+    cmd.clock_q_enable = oldcmd.clock_q_enable;
+    cmd.power_q_enable = oldcmd.power_q_enable;
+    ethosu_dev_write_reg(dev, NPU_REG_CMD, cmd.word);
+    LOG_DEBUG("CMD=0x%08x\n", cmd.word);
+
+    return ETHOSU_SUCCESS;
+}
+
+enum ethosu_error_codes ethosu_dev_soft_reset(struct ethosu_device *dev)
+{
+    enum ethosu_error_codes return_code = ETHOSU_SUCCESS;
+    struct reset_r reset;
+    struct prot_r prot;
+
+    reset.word        = 0;
+    reset.pending_CPL = dev->privileged ? PRIVILEGE_LEVEL_PRIVILEGED : PRIVILEGE_LEVEL_USER;
+    reset.pending_CSL = dev->secure ? SECURITY_LEVEL_SECURE : SECURITY_LEVEL_NON_SECURE;
+
+    // Reset and set security level
+    LOG_INFO("Soft reset NPU\n");
+    ethosu_dev_write_reg(dev, NPU_REG_RESET, reset.word);
+
+    // Wait for reset to complete
+    return_code = ethosu_dev_wait_for_reset(dev);
+    if (return_code != ETHOSU_SUCCESS)
+    {
+        LOG_ERR("Soft reset timed out\n");
+        return return_code;
+    }
+
+    // Verify that NPU has switched security state and privilege level
+    prot.word = ethosu_dev_read_reg(dev, NPU_REG_PROT);
+    if (prot.active_CPL != reset.pending_CPL || prot.active_CSL != reset.pending_CSL)
+    {
+        LOG_ERR("Failed to switch security state and privilege level\n");
+        // Register access not permitted
+        return ETHOSU_GENERIC_FAILURE;
+    }
+
+    // Save the prot register
+    dev->proto = prot.word;
+
+    // Soft reset will clear the PMU configuration and counters. The shadow PMU counters
+    // are cleared by saving the PMU counters to ram, which will read back zeros.
+    // The PMU configuration will be restored in the invoke function after power save
+    // has been disabled.
+    ethosu_dev_save_pmu_counters(dev);
+
+    return return_code;
+}
+
+enum ethosu_error_codes ethosu_dev_wait_for_reset(struct ethosu_device *dev)
+{
+    struct status_r status;
+
+    // Wait until reset status indicates that reset has been completed
+    for (int i = 0; i < 100000; i++)
+    {
+        status.word = ethosu_dev_read_reg(dev, NPU_REG_STATUS);
+        if (0 == status.reset_status)
+        {
+            break;
+        }
+    }
+
+    if (1 == status.reset_status)
+    {
+        return ETHOSU_GENERIC_FAILURE;
+    }
+
+    return ETHOSU_SUCCESS;
+}
+
+enum ethosu_error_codes ethosu_dev_read_apb_reg(struct ethosu_device *dev,
+                                                uint32_t start_address,
+                                                uint16_t num_reg,
+                                                uint32_t *reg)
+{
+    uint32_t address = start_address;
+
+    assert((start_address + num_reg) < ID_REGISTERS_SIZE);
+
+    for (int i = 0; i < num_reg; i++)
+    {
+        reg[i] = ethosu_dev_read_reg(dev, address);
+        address += REG_OFFSET;
+    }
+
+    return ETHOSU_SUCCESS;
+}
+
+enum ethosu_error_codes ethosu_dev_set_qconfig(struct ethosu_device *dev, enum ethosu_memory_type memory_type)
+{
+    if (memory_type > ETHOSU_AXI1_OUTSTANDING_COUNTER3)
+    {
+        return ETHOSU_INVALID_PARAM;
+    }
+    ethosu_dev_write_reg(dev, NPU_REG_QCONFIG, memory_type);
+    LOG_DEBUG("QCONFIG=0x%08x\n", memory_type);
+
+    return ETHOSU_SUCCESS;
+}
+
+enum ethosu_error_codes ethosu_dev_set_regioncfg(struct ethosu_device *dev,
+                                                 uint8_t region,
+                                                 enum ethosu_memory_type memory_type)
+{
+    struct regioncfg_r regioncfg;
+
+    if (region > 7)
+    {
+        return ETHOSU_INVALID_PARAM;
+    }
+
+    regioncfg.word = ethosu_dev_read_reg(dev, NPU_REG_REGIONCFG);
+    regioncfg.word &= ~(0x3 << (2 * region));
+    regioncfg.word |= (memory_type & 0x3) << (2 * region);
+    ethosu_dev_write_reg(dev, NPU_REG_REGIONCFG, regioncfg.word);
+    LOG_DEBUG("REGIONCFG%u=0x%08x\n", region, regioncfg.word);
+
+    return ETHOSU_SUCCESS;
+}
+
+enum ethosu_error_codes ethosu_dev_set_axi_limit0(struct ethosu_device *dev,
+                                                  enum ethosu_axi_limit_beats max_beats,
+                                                  enum ethosu_axi_limit_mem_type memtype,
+                                                  uint8_t max_reads,
+                                                  uint8_t max_writes)
+{
+    struct axi_limit0_r axi_limit0;
+
+    axi_limit0.word                     = 0;
+    axi_limit0.max_beats                = max_beats;
+    axi_limit0.memtype                  = memtype;
+    axi_limit0.max_outstanding_read_m1  = max_reads - 1;
+    axi_limit0.max_outstanding_write_m1 = max_writes - 1;
+
+    ethosu_dev_write_reg(dev, NPU_REG_AXI_LIMIT0, axi_limit0.word);
+    LOG_DEBUG("AXI_LIMIT0=0x%08x\n", axi_limit0.word);
+
+    return ETHOSU_SUCCESS;
+}
+
+enum ethosu_error_codes ethosu_dev_set_axi_limit1(struct ethosu_device *dev,
+                                                  enum ethosu_axi_limit_beats max_beats,
+                                                  enum ethosu_axi_limit_mem_type memtype,
+                                                  uint8_t max_reads,
+                                                  uint8_t max_writes)
+{
+    struct axi_limit1_r axi_limit1;
+
+    axi_limit1.word                     = 0;
+    axi_limit1.max_beats                = max_beats;
+    axi_limit1.memtype                  = memtype;
+    axi_limit1.max_outstanding_read_m1  = max_reads - 1;
+    axi_limit1.max_outstanding_write_m1 = max_writes - 1;
+
+    ethosu_dev_write_reg(dev, NPU_REG_AXI_LIMIT1, axi_limit1.word);
+    LOG_DEBUG("AXI_LIMIT1=0x%08x\n", axi_limit1.word);
+
+    return ETHOSU_SUCCESS;
+}
+
+enum ethosu_error_codes ethosu_dev_set_axi_limit2(struct ethosu_device *dev,
+                                                  enum ethosu_axi_limit_beats max_beats,
+                                                  enum ethosu_axi_limit_mem_type memtype,
+                                                  uint8_t max_reads,
+                                                  uint8_t max_writes)
+{
+    struct axi_limit2_r axi_limit2;
+
+    axi_limit2.word                     = 0;
+    axi_limit2.max_beats                = max_beats;
+    axi_limit2.memtype                  = memtype;
+    axi_limit2.max_outstanding_read_m1  = max_reads - 1;
+    axi_limit2.max_outstanding_write_m1 = max_writes - 1;
+
+    ethosu_dev_write_reg(dev, NPU_REG_AXI_LIMIT2, axi_limit2.word);
+    LOG_DEBUG("AXI_LIMIT2=0x%08x\n", axi_limit2.word);
+
+    return ETHOSU_SUCCESS;
+}
+
+enum ethosu_error_codes ethosu_dev_set_axi_limit3(struct ethosu_device *dev,
+                                                  enum ethosu_axi_limit_beats max_beats,
+                                                  enum ethosu_axi_limit_mem_type memtype,
+                                                  uint8_t max_reads,
+                                                  uint8_t max_writes)
+{
+    struct axi_limit3_r axi_limit3;
+
+    axi_limit3.word                     = 0;
+    axi_limit3.max_beats                = max_beats;
+    axi_limit3.memtype                  = memtype;
+    axi_limit3.max_outstanding_read_m1  = max_reads - 1;
+    axi_limit3.max_outstanding_write_m1 = max_writes - 1;
+
+    ethosu_dev_write_reg(dev, NPU_REG_AXI_LIMIT3, axi_limit3.word);
+    LOG_DEBUG("AXI_LIMIT3=0x%08x\n", axi_limit3.word);
+
+    return ETHOSU_SUCCESS;
+}
+
+enum ethosu_error_codes ethosu_dev_get_revision(struct ethosu_device *dev, uint32_t *revision)
+{
+    *revision = ethosu_dev_read_reg(dev, NPU_REG_REVISION);
+
+    return ETHOSU_SUCCESS;
+}
+
+uint32_t ethosu_dev_get_qread(struct ethosu_device *dev)
+{
+    return ethosu_dev_read_reg(dev, NPU_REG_QREAD);
+}
+
+uint32_t ethosu_dev_get_status(struct ethosu_device *dev)
+{
+    return ethosu_dev_read_reg(dev, NPU_REG_STATUS);
+}
+
+enum ethosu_error_codes ethosu_dev_get_status_mask(struct ethosu_device *dev, uint16_t *status_mask)
+{
+    struct status_r status;
+
+    status.word  = ethosu_dev_read_reg(dev, NPU_REG_STATUS);
+    *status_mask = status.word & 0xFFFF;
+
+    return ETHOSU_SUCCESS;
+}
+
+enum ethosu_error_codes ethosu_dev_get_irq_history_mask(struct ethosu_device *dev, uint16_t *irq_history_mask)
+{
+    struct status_r status;
+
+    status.word       = ethosu_dev_read_reg(dev, NPU_REG_STATUS);
+    *irq_history_mask = status.irq_history_mask;
+
+    return ETHOSU_SUCCESS;
+}
+
+enum ethosu_error_codes ethosu_dev_clear_irq_history_mask(struct ethosu_device *dev, uint16_t irq_history_clear_mask)
+{
+    struct cmd_r oldcmd;
+    struct cmd_r cmd;
+
+    oldcmd.word = ethosu_dev_read_reg(dev, NPU_REG_CMD);
+
+    cmd.word              = 0;
+    cmd.clock_q_enable    = oldcmd.clock_q_enable;
+    cmd.power_q_enable    = oldcmd.power_q_enable;
+    cmd.clear_irq_history = irq_history_clear_mask;
+
+    ethosu_dev_write_reg(dev, NPU_REG_CMD, cmd.word);
+    LOG_DEBUG("CMD=0x%08x\n", cmd.word);
+
+    return ETHOSU_SUCCESS;
+}
+
+enum ethosu_error_codes ethosu_dev_set_command_run(struct ethosu_device *dev)
+{
+    struct cmd_r oldcmd;
+    struct cmd_r cmd;
+
+    oldcmd.word = ethosu_dev_read_reg(dev, NPU_REG_CMD);
+
+    cmd.word                        = 0;
+    cmd.transition_to_running_state = 1;
+    cmd.clock_q_enable              = oldcmd.clock_q_enable;
+    cmd.power_q_enable              = oldcmd.power_q_enable;
+
+    ethosu_dev_write_reg(dev, NPU_REG_CMD, cmd.word);
+    LOG_DEBUG("CMD=0x%08x\n", cmd.word);
+
+    return ETHOSU_SUCCESS;
+}
+
+enum ethosu_error_codes ethosu_dev_get_shram_data(struct ethosu_device *dev, int section, uint32_t *shram_p)
+{
+    int i            = 0;
+    uint32_t address = NPU_REG_SHARED_BUFFER0;
+
+    ethosu_dev_write_reg(dev, NPU_REG_DEBUG_ADDRESS, section * BYTES_1KB);
+
+    while (address <= NPU_REG_SHARED_BUFFER255)
+    {
+        shram_p[i] = ethosu_dev_read_reg(dev, address);
+        address += REG_OFFSET;
+        i++;
+    }
+
+    return ETHOSU_SUCCESS;
+}
+
+enum ethosu_error_codes ethosu_dev_set_clock_and_power(struct ethosu_device *dev,
+                                                       enum ethosu_clock_q_request clock_q,
+                                                       enum ethosu_power_q_request power_q)
+{
+    struct cmd_r cmd;
+
+    cmd.word           = 0;
+    cmd.clock_q_enable = clock_q;
+    cmd.power_q_enable = power_q;
+    ethosu_dev_write_reg(dev, NPU_REG_CMD, cmd.word);
+    LOG_DEBUG("CMD=0x%08x\n", cmd.word);
+
+    return ETHOSU_SUCCESS;
+}
+
+uint32_t ethosu_dev_read_reg(struct ethosu_device *dev, uint32_t address)
+{
+    assert(dev->base_address != 0);
+    assert(address % 4 == 0);
+
+    volatile uint32_t *reg = (volatile uint32_t *)(dev->base_address + address);
+    return *reg;
+}
+
+void ethosu_dev_write_reg(struct ethosu_device *dev, uint32_t address, uint32_t value)
+{
+    assert(dev->base_address != 0);
+    assert(address % 4 == 0);
+
+    volatile uint32_t *reg = (volatile uint32_t *)(dev->base_address + address);
+    *reg                   = value;
+}
+
+void ethosu_dev_write_reg_shadow(struct ethosu_device *dev, uint32_t address, uint32_t value, uint32_t *shadow)
+{
+    ethosu_dev_write_reg(dev, address, value);
+    *shadow = ethosu_dev_read_reg(dev, address);
+}
+
+enum ethosu_error_codes ethosu_dev_save_pmu_config(struct ethosu_device *dev)
+{
+    // Save the PMU control register
+    dev->pmcr = ethosu_dev_read_reg(dev, NPU_REG_PMCR);
+
+    // Save IRQ control
+    dev->pmint = ethosu_dev_read_reg(dev, NPU_REG_PMINTSET);
+
+    // Save the enabled events mask
+    dev->pmcnten = ethosu_dev_read_reg(dev, NPU_REG_PMCNTENSET);
+
+    // Save start and stop event
+    dev->pmccntr_cfg = ethosu_dev_read_reg(dev, NPU_REG_PMCCNTR_CFG);
+
+    // Save the event settings and counters
+    for (uint32_t i = 0; i < ETHOSU_PMU_NCOUNTERS; i++)
+    {
+        dev->pmu_evtypr[i] = ethosu_dev_read_reg(dev, NPU_REG_PMEVTYPER0 + i * sizeof(uint32_t));
+    }
+
+    return ETHOSU_SUCCESS;
+}
+
+enum ethosu_error_codes ethosu_dev_restore_pmu_config(struct ethosu_device *dev)
+{
+    // Restore PMU control register
+    ethosu_dev_write_reg(dev, NPU_REG_PMCR, dev->pmcr);
+
+    // Restore IRQ control
+    ethosu_dev_write_reg(dev, NPU_REG_PMINTSET, dev->pmint);
+
+    // Restore enabled event mask
+    ethosu_dev_write_reg(dev, NPU_REG_PMCNTENSET, dev->pmcnten);
+
+    // Restore start and stop event
+    ethosu_dev_write_reg(dev, NPU_REG_PMCCNTR_CFG, dev->pmccntr_cfg);
+
+    // Save the event settings and counters
+    for (uint32_t i = 0; i < ETHOSU_PMU_NCOUNTERS; i++)
+    {
+        ethosu_dev_write_reg(dev, NPU_REG_PMEVTYPER0 + i * sizeof(uint32_t), dev->pmu_evtypr[i]);
+    }
+
+    return ETHOSU_SUCCESS;
+}
+
+enum ethosu_error_codes ethosu_dev_save_pmu_counters(struct ethosu_device *dev)
+{
+    // Save the cycle counter
+    dev->pmccntr[0] = ethosu_dev_read_reg(dev, NPU_REG_PMCCNTR_LO);
+    dev->pmccntr[1] = ethosu_dev_read_reg(dev, NPU_REG_PMCCNTR_HI);
+
+    // Save the event settings and counters
+    for (uint32_t i = 0; i < ETHOSU_PMU_NCOUNTERS; i++)
+    {
+        dev->pmu_evcntr[i] = ethosu_dev_read_reg(dev, NPU_REG_PMEVCNTR0 + i * sizeof(uint32_t));
+    }
+
+    return ETHOSU_SUCCESS;
+}
+
+bool ethosu_dev_prot_has_changed(struct ethosu_device *dev)
+{
+    if (dev->proto != ethosu_dev_read_reg(dev, NPU_REG_PROT))
+    {
+        return true;
+    }
+
+    return false;
+}
+
+bool ethosu_dev_status_has_error(struct ethosu_device *dev)
+{
+    bool status_error = false;
+    struct status_r status;
+
+    status.word  = ethosu_dev_read_reg(dev, NPU_REG_STATUS);
+    status_error = ((1 == status.bus_status) || (1 == status.cmd_parse_error) || (1 == status.wd_fault) ||
+                    (1 == status.ecc_fault));
+
+    return status_error;
+}
diff --git a/src/ethosu_driver.c b/src/ethosu_driver.c
index 4c1b100..84488e5 100644
--- a/src/ethosu_driver.c
+++ b/src/ethosu_driver.c
@@ -147,30 +147,51 @@ struct opt_cfg_s
 };
 
 /******************************************************************************
- * Functions
+ * Variables
  ******************************************************************************/
 
-struct ethosu_driver ethosu_drv = {
-    .dev = {.base_address = NULL, .proto = 0, .pmccntr = {0}, .pmu_evcntr = {0, 0, 0, 0}, .pmu_evtypr = {0, 0, 0, 0}},
-    .abort_inference     = false,
-    .status_error        = false,
-    .dev_power_always_on = false};
-
 // Registered drivers linked list HEAD
 static struct ethosu_driver *registered_drivers = NULL;
 
+/******************************************************************************
+ * Weak functions - Cache
+ *
+ * Default NOP operations. Override if available on the targeted device.
+ ******************************************************************************/
+
+/*
+ * Flush/clean the data cache by address and size. Passing NULL as p argument
+ * expects the whole cache to be flushed.
+ */
+void __attribute__((weak)) ethosu_flush_dcache(uint32_t *p, size_t bytes)
+{
+    UNUSED(p);
+    UNUSED(bytes);
+}
+
 /*
- * Following section handles the minimal sempahore and mutex implementation in case of baremetal applications.
- * Weak symbols will be overwritten by RTOS definitions and implement true thread-safety. (Done in application layer)
+ * Invalidate the data cache by address and size. Passing NULL as p argument
+ * expects the whole cache to be invalidated.
  */
+void __attribute__((weak)) ethosu_invalidate_dcache(uint32_t *p, size_t bytes)
+{
+    UNUSED(p);
+    UNUSED(bytes);
+}
+
+/******************************************************************************
+ * Weak functions - Semaphore/Mutex for multi NPU
+ *
+ * Following section handles the minimal sempahore and mutex implementation in
+ * case of baremetal applications. Weak symbols will be overridden by RTOS
+ * definitions and implement true thread-safety (in application layer).
+ ******************************************************************************/
 
-// Baremetal sempahore implementation
 struct ethosu_semaphore_t
 {
     int count;
 };
 
-// Minimal needed declaration to allow baremetal functionality.
 static void *ethosu_mutex;
 static void *ethosu_semaphore;
 
@@ -215,351 +236,85 @@ void __attribute__((weak)) ethosu_semaphore_give(void *sem)
     s->count++;
     __SEV();
 }
-// <--- End of semaphore and mutex implementations
 
-static int ethosu_soft_reset_and_restore(struct ethosu_driver *drv);
-
-void __attribute__((weak)) ethosu_irq_handler(struct ethosu_driver *drv)
-{
-    uint8_t irq_raised = 0;
-
-    LOG_DEBUG("Interrupt. status=0x%08x, qread=%d\n",
-              ethosu_read_reg(&drv->dev, NPU_REG_STATUS),
-              ethosu_read_reg(&drv->dev, NPU_REG_QREAD));
-
-    // Verify that interrupt has been raised
-    (void)ethosu_is_irq_raised(&drv->dev, &irq_raised);
-    assert(irq_raised == 1);
-    drv->irq_triggered = true;
-
-    // Clear interrupt
-    (void)ethosu_clear_irq_status(&drv->dev);
-
-    // Verify that interrupt has been successfully cleared
-    (void)ethosu_is_irq_raised(&drv->dev, &irq_raised);
-    assert(irq_raised == 0);
-
-    if (ethosu_status_has_error(&drv->dev))
-    {
-        ethosu_soft_reset_and_restore(drv);
-        drv->status_error = true;
-    }
-
-    ethosu_semaphore_give(drv->semaphore);
-}
-
-static inline void wait_for_irq(struct ethosu_driver *drv)
-{
-    while (1)
-    {
-        if (drv->irq_triggered || drv->abort_inference)
-        {
-            drv->irq_triggered = false;
-            break;
-        }
-
-        ethosu_semaphore_take(drv->semaphore);
-    }
-}
+/******************************************************************************
+ * Weak functions - Inference begin/end callbacks
+ ******************************************************************************/
 
 void __attribute__((weak)) ethosu_inference_begin(struct ethosu_driver *drv, const void *inference_data)
 {
-    (void)inference_data;
-    (void)drv;
+    UNUSED(inference_data);
+    UNUSED(drv);
 }
 
 void __attribute__((weak)) ethosu_inference_end(struct ethosu_driver *drv, const void *inference_data)
 {
-    (void)inference_data;
-    (void)drv;
-}
-
-static int handle_optimizer_config(struct ethosu_driver *drv, struct opt_cfg_s *opt_cfg_p);
-static int handle_command_stream(struct ethosu_driver *drv,
-                                 const uint8_t *cmd_stream,
-                                 const int cms_length,
-                                 const uint64_t *base_addr,
-                                 const size_t *base_addr_size,
-                                 const int num_base_addr);
-static int read_apb_reg(struct ethosu_driver *drv, uint16_t);
-static int dump_shram(struct ethosu_driver *drv);
-static void dump_npu_register(struct ethosu_driver *drv, int npu_reg, int npu_reg_end);
-static void dump_command_stream(const uint32_t *cmd_stream, const int cms_length, int qread);
-static void npu_axi_init(struct ethosu_driver *drv);
-static struct ethosu_driver *ethosu_find_and_reserve_driver(void);
-
-int ethosu_init(struct ethosu_driver *drv,
-                const void *base_address,
-                const void *fast_memory,
-                const size_t fast_memory_size,
-                uint32_t secure_enable,
-                uint32_t privilege_enable)
-{
-    int return_code = 0;
-
-    LOG_INFO("%s. base_address=%p, fast_memory=%p, fast_memory_size=%zu, secure=%" PRIu32 ", privileged=%" PRIu32 "\n",
-             __FUNCTION__,
-             base_address,
-             fast_memory,
-             fast_memory_size,
-             secure_enable,
-             privilege_enable);
-
-    if (!ethosu_mutex)
-    {
-        ethosu_mutex = ethosu_mutex_create();
-    }
-
-    if (!ethosu_semaphore)
-    {
-        ethosu_semaphore = ethosu_semaphore_create();
-    }
-
-    ethosu_register_driver(drv);
-
-    drv->fast_memory      = (uint32_t)fast_memory;
-    drv->fast_memory_size = fast_memory_size;
-    drv->irq_triggered    = false;
-    drv->semaphore        = ethosu_semaphore_create();
-
-    if (ETHOSU_SUCCESS != ethosu_dev_init(&drv->dev, base_address, secure_enable, privilege_enable))
-    {
-        LOG_ERR("Failed in ethosu_dev_init");
-        return -1;
-    }
-
-    if (ETHOSU_SUCCESS !=
-        set_clock_and_power_request(drv, ETHOSU_INFERENCE_REQUEST, ETHOSU_CLOCK_Q_DISABLE, ETHOSU_POWER_Q_DISABLE))
-    {
-        LOG_ERR("Failed to disable clock-q & power-q for Ethos-U\n");
-        return -1;
-    }
-
-    if (ETHOSU_SUCCESS != ethosu_soft_reset(&drv->dev))
-    {
-        return -1;
-    }
-
-    if (ETHOSU_SUCCESS != ethosu_wait_for_reset(&drv->dev))
-    {
-        LOG_ERR("Failed reset of Ethos-U\n");
-        return -1;
-    }
-
-    drv->status_error = false;
-
-    return return_code;
-}
-
-int ethosu_get_version(struct ethosu_driver *drv, struct ethosu_version *version)
-{
-    int return_code = 0;
-
-    if (NULL != version)
-    {
-        struct ethosu_id id;
-        struct ethosu_config cfg;
-        (void)ethosu_get_id(&drv->dev, &id);
-        (void)ethosu_get_config(&drv->dev, &cfg);
-
-        version->id.version_status      = id.version_status;
-        version->id.version_minor       = id.version_minor;
-        version->id.version_major       = id.version_major;
-        version->id.product_major       = id.product_major;
-        version->id.arch_patch_rev      = id.arch_patch_rev;
-        version->id.arch_minor_rev      = id.arch_minor_rev;
-        version->id.arch_major_rev      = id.arch_major_rev;
-        version->id.driver_patch_rev    = ETHOSU_DRIVER_VERSION_PATCH;
-        version->id.driver_minor_rev    = ETHOSU_DRIVER_VERSION_MINOR;
-        version->id.driver_major_rev    = ETHOSU_DRIVER_VERSION_MAJOR;
-        version->cfg.macs_per_cc        = cfg.macs_per_cc;
-        version->cfg.cmd_stream_version = cfg.cmd_stream_version;
-        version->cfg.shram_size         = cfg.shram_size;
-        version->cfg.custom_dma         = cfg.custom_dma;
-    }
-    else
-    {
-        return_code = -1;
-    }
-
-    return return_code;
+    UNUSED(inference_data);
+    UNUSED(drv);
 }
 
-int ethosu_invoke(struct ethosu_driver *drv,
-                  const void *custom_data_ptr,
-                  const int custom_data_size,
-                  const uint64_t *base_addr,
-                  const size_t *base_addr_size,
-                  const int num_base_addr)
+/******************************************************************************
+ * Static functions
+ ******************************************************************************/
+static inline void wait_for_irq(struct ethosu_driver *drv)
 {
-    const struct custom_data_s *data_ptr = custom_data_ptr;
-    const struct custom_data_s *data_end = custom_data_ptr + custom_data_size;
-    int return_code                      = 0;
-
-    LOG_INFO("%s\n", __FUNCTION__);
-
-    // First word in custom_data_ptr should contain "Custom Operator Payload 1"
-    if (data_ptr->word != ETHOSU_FOURCC)
-    {
-        LOG_ERR("Custom Operator Payload: %" PRIu32 " is not correct, expected %x\n", data_ptr->word, ETHOSU_FOURCC);
-        return -1;
-    }
-
-    // Custom data length must be a multiple of 32 bits
-    if ((custom_data_size % BYTES_IN_32_BITS) != 0)
-    {
-        LOG_ERR("ethosu_invoke ERROR custom_data_size=0x%x not a multiple of 4\n", custom_data_size);
-        return -1;
-    }
-
-    ++data_ptr;
-
-    // Adjust base address to fast memory area
-    if (drv->fast_memory != 0 && num_base_addr >= FAST_MEMORY_BASE_ADDR_INDEX)
-    {
-        uint64_t *fast_memory = (uint64_t *)&base_addr[FAST_MEMORY_BASE_ADDR_INDEX];
-
-        if (base_addr_size != NULL && base_addr_size[FAST_MEMORY_BASE_ADDR_INDEX] > drv->fast_memory_size)
-        {
-            LOG_ERR("Fast memory area too small. fast_memory_size=%u, base_addr_size=%u\n",
-                    drv->fast_memory_size,
-                    base_addr_size[FAST_MEMORY_BASE_ADDR_INDEX]);
-            return -1;
-        }
-
-        *fast_memory = drv->fast_memory;
-    }
-
-    if (!drv->dev_power_always_on)
-    {
-        // Only soft reset if securty state or privilege level needs changing
-        if (drv->dev.proto != ethosu_read_reg(&drv->dev, NPU_REG_PROT))
-        {
-            if (ETHOSU_SUCCESS != ethosu_soft_reset(&drv->dev))
-            {
-                return -1;
-            }
-        }
-
-        drv->status_error = false;
-        set_clock_and_power_request(drv, ETHOSU_INFERENCE_REQUEST, ETHOSU_CLOCK_Q_ENABLE, ETHOSU_POWER_Q_DISABLE);
-        ethosu_restore_pmu_config(&drv->dev);
-        npu_axi_init(drv);
-    }
-
-    drv->status_error = false;
-
-    ethosu_inference_begin(drv, custom_data_ptr);
-    while (data_ptr < data_end)
+    while (1)
     {
-        int ret = 0;
-        switch (data_ptr->driver_action_command)
+        if (drv->irq_triggered || drv->abort_inference)
         {
-        case OPTIMIZER_CONFIG:
-            LOG_INFO("ethosu_invoke OPTIMIZER_CONFIG\n");
-            struct opt_cfg_s *opt_cfg_p = (struct opt_cfg_s *)data_ptr;
-
-            ret = handle_optimizer_config(drv, opt_cfg_p);
-            data_ptr += DRIVER_ACTION_LENGTH_32_BIT_WORD + OPTIMIZER_CONFIG_LENGTH_32_BIT_WORD;
-            break;
-        case COMMAND_STREAM:
-            LOG_INFO("ethosu_invoke COMMAND_STREAM\n");
-            void *command_stream = (uint8_t *)(data_ptr) + sizeof(struct custom_data_s);
-            int cms_length       = (data_ptr->reserved << 16) | data_ptr->length;
-
-            drv->abort_inference = false;
-            // It is safe to clear this flag without atomic, because npu is not running.
             drv->irq_triggered = false;
-
-            ret = handle_command_stream(drv, command_stream, cms_length, base_addr, base_addr_size, num_base_addr);
-
-            if (return_code == -1 && drv->abort_inference)
-            {
-                uint32_t qread = 0;
-                ethosu_get_qread(&drv->dev, &qread);
-                LOG_ERR("NPU timeout\n");
-                dump_command_stream(command_stream, cms_length, qread);
-                dump_npu_register(drv, 0x200, 0x2BF);
-                dump_npu_register(drv, 0x800, 0xB3F);
-                dump_shram(drv);
-            }
-
-            data_ptr += DRIVER_ACTION_LENGTH_32_BIT_WORD + cms_length;
-            break;
-        case READ_APB_REG:
-            LOG_INFO("ethosu_invoke READ_APB_REG\n");
-            ret = read_apb_reg(drv, data_ptr->driver_action_data);
-            data_ptr += DRIVER_ACTION_LENGTH_32_BIT_WORD;
-            break;
-        case DUMP_SHRAM:
-            LOG_INFO("ethosu_invoke DUMP_SHRAM\n");
-            ret = dump_shram(drv);
-            data_ptr += DRIVER_ACTION_LENGTH_32_BIT_WORD;
-            break;
-        case NOP:
-            LOG_INFO("ethosu_invoke NOP\n");
-            data_ptr += DRIVER_ACTION_LENGTH_32_BIT_WORD;
-            break;
-        default:
-            LOG_ERR("ethosu_invoke UNSUPPORTED driver_action_command %d \n", data_ptr->driver_action_command);
-            ret = -1;
             break;
         }
-        if (ret != 0)
-        {
-            return_code = -1;
-            break;
-        }
-    }
-    ethosu_inference_end(drv, custom_data_ptr);
-
-    if (!drv->status_error && !drv->dev_power_always_on)
-    {
-        ethosu_save_pmu_counters(&drv->dev);
-        set_clock_and_power_request(drv, ETHOSU_INFERENCE_REQUEST, ETHOSU_CLOCK_Q_ENABLE, ETHOSU_POWER_Q_ENABLE);
-    }
-
-    return return_code;
-}
-
-void ethosu_abort(struct ethosu_driver *drv)
-{
-    drv->abort_inference = true;
-}
 
-void ethosu_set_power_mode(struct ethosu_driver *drv, bool always_on)
-{
-    drv->dev_power_always_on = always_on;
-
-    if (always_on)
-    {
-        npu_axi_init(drv);
+        ethosu_semaphore_take(drv->semaphore);
     }
 }
 
-int ethosu_register_driver(struct ethosu_driver *drv)
+static void npu_axi_init(struct ethosu_driver *drv)
 {
-    // Safeguard check for if driver is already registered
-    struct ethosu_driver *cur = registered_drivers;
-    while (cur != NULL)
-    {
-        if (cur == drv)
-        {
-            LOG_ERR("%s: NPU driver at address %p is already registered.\n", __FUNCTION__, drv);
-            return -1;
-        }
-        cur = cur->next;
-    }
-
-    drv->next = registered_drivers;
-    // Designate new registered driver HEAD
+    ethosu_dev_set_qconfig(&drv->dev, NPU_QCONFIG);
+
+    ethosu_dev_set_regioncfg(&drv->dev, 0, NPU_REGIONCFG_0);
+    ethosu_dev_set_regioncfg(&drv->dev, 1, NPU_REGIONCFG_1);
+    ethosu_dev_set_regioncfg(&drv->dev, 2, NPU_REGIONCFG_2);
+    ethosu_dev_set_regioncfg(&drv->dev, 3, NPU_REGIONCFG_3);
+    ethosu_dev_set_regioncfg(&drv->dev, 4, NPU_REGIONCFG_4);
+    ethosu_dev_set_regioncfg(&drv->dev, 5, NPU_REGIONCFG_5);
+    ethosu_dev_set_regioncfg(&drv->dev, 6, NPU_REGIONCFG_6);
+    ethosu_dev_set_regioncfg(&drv->dev, 7, NPU_REGIONCFG_7);
+
+    (void)ethosu_dev_set_axi_limit0(&drv->dev,
+                                    AXI_LIMIT0_MAX_BEATS_BYTES,
+                                    AXI_LIMIT0_MEM_TYPE,
+                                    AXI_LIMIT0_MAX_OUTSTANDING_READS,
+                                    AXI_LIMIT0_MAX_OUTSTANDING_WRITES);
+    (void)ethosu_dev_set_axi_limit1(&drv->dev,
+                                    AXI_LIMIT1_MAX_BEATS_BYTES,
+                                    AXI_LIMIT1_MEM_TYPE,
+                                    AXI_LIMIT1_MAX_OUTSTANDING_READS,
+                                    AXI_LIMIT1_MAX_OUTSTANDING_WRITES);
+    (void)ethosu_dev_set_axi_limit2(&drv->dev,
+                                    AXI_LIMIT2_MAX_BEATS_BYTES,
+                                    AXI_LIMIT2_MEM_TYPE,
+                                    AXI_LIMIT2_MAX_OUTSTANDING_READS,
+                                    AXI_LIMIT2_MAX_OUTSTANDING_WRITES);
+    (void)ethosu_dev_set_axi_limit3(&drv->dev,
+                                    AXI_LIMIT3_MAX_BEATS_BYTES,
+                                    AXI_LIMIT3_MEM_TYPE,
+                                    AXI_LIMIT3_MAX_OUTSTANDING_READS,
+                                    AXI_LIMIT3_MAX_OUTSTANDING_WRITES);
+}
+
+static void ethosu_register_driver(struct ethosu_driver *drv)
+{
+    // Register driver as new HEAD of list
+    drv->next          = registered_drivers;
     registered_drivers = drv;
 
-    LOG_INFO("%s: New NPU driver at address %p is registered.\n", __FUNCTION__, drv);
-    return 0;
+    LOG_INFO("New NPU driver registered (handle: 0x%p, NPU: 0x%x)", drv, drv->dev.base_address);
 }
 
-int ethosu_deregister_driver(struct ethosu_driver *drv)
+static int ethosu_deregister_driver(struct ethosu_driver *drv)
 {
     struct ethosu_driver *cur   = registered_drivers;
     struct ethosu_driver **prev = &registered_drivers;
@@ -569,7 +324,7 @@ int ethosu_deregister_driver(struct ethosu_driver *drv)
         if (cur == drv)
         {
             *prev = cur->next;
-            LOG_INFO("%s: NPU driver at address %p is deregistered.\n", __FUNCTION__, drv);
+            LOG_INFO("NPU driver handle %p deregistered.", drv);
             return 0;
         }
 
@@ -577,36 +332,11 @@ int ethosu_deregister_driver(struct ethosu_driver *drv)
         cur  = cur->next;
     }
 
-    LOG_ERR("%s: NPU driver at address %p does not match a registered driver and therefore may not be deregistered.\n",
-            __FUNCTION__,
-            drv);
+    LOG_ERR("No NPU driver handle registered at address %p.", drv);
 
     return -1;
 }
 
-struct ethosu_driver *ethosu_reserve_driver(void)
-{
-    struct ethosu_driver *drv = NULL;
-
-    do
-    {
-        ethosu_mutex_lock(ethosu_mutex);
-        drv = ethosu_find_and_reserve_driver();
-        ethosu_mutex_unlock(ethosu_mutex);
-
-        if (drv != NULL)
-        {
-            break;
-        }
-
-        LOG_INFO("%s - Waiting for driver \n", __FUNCTION__);
-        ethosu_semaphore_take(ethosu_semaphore);
-
-    } while (1);
-
-    return drv;
-}
-
 static struct ethosu_driver *ethosu_find_and_reserve_driver(void)
 {
     struct ethosu_driver *drv = registered_drivers;
@@ -616,33 +346,21 @@ static struct ethosu_driver *ethosu_find_and_reserve_driver(void)
         if (!drv->reserved)
         {
             drv->reserved = true;
-            LOG_INFO("%s - Driver %p reserved.\n", __FUNCTION__, drv);
+            LOG_DEBUG("NPU driver handle %p reserved.", drv);
             return drv;
         }
         drv = drv->next;
     }
 
-    LOG_INFO("%s: No available drivers.\n", __FUNCTION__, drv);
+    LOG_DEBUG("No NPU driver handle available.", drv);
 
     return NULL;
 }
 
-void ethosu_release_driver(struct ethosu_driver *drv)
-{
-    ethosu_mutex_lock(ethosu_mutex);
-    if (drv != NULL && drv->reserved)
-    {
-        drv->reserved = false;
-        LOG_INFO("%s - Driver %p released\n", __FUNCTION__, drv);
-        ethosu_semaphore_give(ethosu_semaphore);
-    }
-    ethosu_mutex_unlock(ethosu_mutex);
-}
-
 static int ethosu_soft_reset_and_restore(struct ethosu_driver *drv)
 {
 
-    if (ETHOSU_SUCCESS != ethosu_soft_reset(&drv->dev))
+    if (ETHOSU_SUCCESS != ethosu_dev_soft_reset(&drv->dev))
     {
         return -1;
     }
@@ -650,73 +368,37 @@ static int ethosu_soft_reset_and_restore(struct ethosu_driver *drv)
     set_clock_and_power_request(drv, ETHOSU_INFERENCE_REQUEST, ETHOSU_CLOCK_Q_ENABLE, ETHOSU_POWER_Q_DISABLE);
 
     npu_axi_init(drv);
-    ethosu_restore_pmu_config(&drv->dev);
+    ethosu_dev_restore_pmu_config(&drv->dev);
 
     return 0;
 }
 
-enum ethosu_error_codes set_clock_and_power_request(struct ethosu_driver *drv,
-                                                    enum ethosu_request_clients client,
-                                                    enum ethosu_clock_q_request clock_request,
-                                                    enum ethosu_power_q_request power_request)
-{
-    // Set clock request bit for client
-    if (clock_request == ETHOSU_CLOCK_Q_DISABLE)
-    {
-        drv->clock_request |= (1 << client);
-    }
-    else
-    {
-        drv->clock_request &= ~(1 << client);
-    }
-    // Get current clock request (ENABLE if both PMU and INFERENCE asks for clock request, else DISABLE)
-    clock_request = drv->clock_request == 0 ? ETHOSU_CLOCK_Q_ENABLE : ETHOSU_CLOCK_Q_DISABLE;
-
-    // Set power request bit for client
-    if (power_request == ETHOSU_POWER_Q_DISABLE)
-    {
-        drv->power_request |= (1 << client);
-    }
-    else
-    {
-        drv->power_request &= ~(1 << client);
-    }
-    // Get current power request (ENABLE if both PMU and INFERENCE asks for power request, else DISABLE)
-    power_request = drv->power_request == 0 ? ETHOSU_POWER_Q_ENABLE : ETHOSU_POWER_Q_DISABLE;
-
-    // Set clock and power
-    enum ethosu_error_codes ret = ethosu_set_clock_and_power(&drv->dev, clock_request, power_request);
-
-    return ret;
-}
-
 static int handle_optimizer_config(struct ethosu_driver *drv, struct opt_cfg_s *opt_cfg_p)
 {
     struct ethosu_config cfg;
     struct ethosu_id id;
     int return_code = 0;
 
-    LOG_INFO("handle_optimizer_config:\n");
-    LOG_INFO("Optimizer release nbr: %d patch: %d\n", opt_cfg_p->da_data.rel_nbr, opt_cfg_p->da_data.patch_nbr);
-    LOG_INFO("Optimizer config cmd_stream_version: %d macs_per_cc: %d shram_size: %d custom_dma: %d\n",
+    LOG_INFO("Optimizer release nbr: %d patch: %d", opt_cfg_p->da_data.rel_nbr, opt_cfg_p->da_data.patch_nbr);
+    LOG_INFO("Optimizer config cmd_stream_version: %d macs_per_cc: %d shram_size: %d custom_dma: %d",
              opt_cfg_p->cmd_stream_version,
              opt_cfg_p->macs_per_cc,
              opt_cfg_p->shram_size,
              opt_cfg_p->custom_dma);
-    LOG_INFO("Optimizer config Ethos-U version: %d.%d.%d\n",
+    LOG_INFO("Optimizer config Ethos-U version: %d.%d.%d",
              opt_cfg_p->arch_major_rev,
              opt_cfg_p->arch_minor_rev,
              opt_cfg_p->arch_patch_rev);
 
-    (void)ethosu_get_config(&drv->dev, &cfg);
-    (void)ethosu_get_id(&drv->dev, &id);
+    (void)ethosu_dev_get_config(&drv->dev, &cfg);
+    (void)ethosu_dev_get_id(&drv->dev, &id);
     LOG_INFO("Ethos-U config cmd_stream_version: %" PRIu32 " macs_per_cc: %" PRIu32 " shram_size: %" PRIu32
-             " custom_dma: %" PRIu32 "\n",
+             " custom_dma: %" PRIu32 "",
              cfg.cmd_stream_version,
              cfg.macs_per_cc,
              cfg.shram_size,
              cfg.custom_dma);
-    LOG_INFO("Ethos-U version: %" PRIu32 ".%" PRIu32 ".%" PRIu32 "\n",
+    LOG_INFO("Ethos-U version: %" PRIu32 ".%" PRIu32 ".%" PRIu32 "",
              id.arch_major_rev,
              id.arch_minor_rev,
              id.arch_patch_rev);
@@ -726,25 +408,25 @@ static int handle_optimizer_config(struct ethosu_driver *drv, struct opt_cfg_s *
     {
         if (cfg.macs_per_cc != opt_cfg_p->macs_per_cc)
         {
-            LOG_ERR("NPU config mismatch: npu.macs_per_cc=%" PRIu32 " optimizer.macs_per_cc=%d\n",
+            LOG_ERR("NPU config mismatch: npu.macs_per_cc=%" PRIu32 " optimizer.macs_per_cc=%d",
                     cfg.macs_per_cc,
                     opt_cfg_p->macs_per_cc);
         }
         if (cfg.shram_size != opt_cfg_p->shram_size)
         {
-            LOG_ERR("NPU config mismatch: npu.shram_size=%" PRIu32 " optimizer.shram_size=%d\n",
+            LOG_ERR("NPU config mismatch: npu.shram_size=%" PRIu32 " optimizer.shram_size=%d",
                     cfg.shram_size,
                     opt_cfg_p->shram_size);
         }
         if (cfg.cmd_stream_version != opt_cfg_p->cmd_stream_version)
         {
-            LOG_ERR("NPU config mismatch: npu.cmd_stream_version=%" PRIu32 " optimizer.cmd_stream_version=%d\n",
+            LOG_ERR("NPU config mismatch: npu.cmd_stream_version=%" PRIu32 " optimizer.cmd_stream_version=%d",
                     cfg.cmd_stream_version,
                     opt_cfg_p->cmd_stream_version);
         }
         if (!cfg.custom_dma && opt_cfg_p->custom_dma)
         {
-            LOG_ERR("NPU config mismatch: npu.custom_dma=%" PRIu32 " optimize.custom_dma=%d\n",
+            LOG_ERR("NPU config mismatch: npu.custom_dma=%" PRIu32 " optimize.custom_dma=%d",
                     cfg.custom_dma,
                     opt_cfg_p->custom_dma);
         }
@@ -753,7 +435,7 @@ static int handle_optimizer_config(struct ethosu_driver *drv, struct opt_cfg_s *
 
     if ((id.arch_major_rev != opt_cfg_p->arch_major_rev) || (id.arch_minor_rev < opt_cfg_p->arch_minor_rev))
     {
-        LOG_ERR("NPU arch mismatch: npu.arch=%" PRIu32 ".%" PRIu32 ".%" PRIu32 " optimizer.arch=%d.%d.%d\n",
+        LOG_ERR("NPU arch mismatch: npu.arch=%" PRIu32 ".%" PRIu32 ".%" PRIu32 " optimizer.arch=%d.%d.%d",
                 id.arch_major_rev,
                 id.arch_minor_rev,
                 id.arch_patch_rev,
@@ -769,59 +451,6 @@ static int handle_optimizer_config(struct ethosu_driver *drv, struct opt_cfg_s *
     return return_code;
 }
 
-static void npu_axi_init(struct ethosu_driver *drv)
-{
-    ethosu_set_qconfig(&drv->dev, NPU_QCONFIG);
-
-    ethosu_set_regioncfg(&drv->dev, 0, NPU_REGIONCFG_0);
-    ethosu_set_regioncfg(&drv->dev, 1, NPU_REGIONCFG_1);
-    ethosu_set_regioncfg(&drv->dev, 2, NPU_REGIONCFG_2);
-    ethosu_set_regioncfg(&drv->dev, 3, NPU_REGIONCFG_3);
-    ethosu_set_regioncfg(&drv->dev, 4, NPU_REGIONCFG_4);
-    ethosu_set_regioncfg(&drv->dev, 5, NPU_REGIONCFG_5);
-    ethosu_set_regioncfg(&drv->dev, 6, NPU_REGIONCFG_6);
-    ethosu_set_regioncfg(&drv->dev, 7, NPU_REGIONCFG_7);
-
-    (void)ethosu_set_axi_limit0(&drv->dev,
-                                AXI_LIMIT0_MAX_BEATS_BYTES,
-                                AXI_LIMIT0_MEM_TYPE,
-                                AXI_LIMIT0_MAX_OUTSTANDING_READS,
-                                AXI_LIMIT0_MAX_OUTSTANDING_WRITES);
-    (void)ethosu_set_axi_limit1(&drv->dev,
-                                AXI_LIMIT1_MAX_BEATS_BYTES,
-                                AXI_LIMIT1_MEM_TYPE,
-                                AXI_LIMIT1_MAX_OUTSTANDING_READS,
-                                AXI_LIMIT1_MAX_OUTSTANDING_WRITES);
-    (void)ethosu_set_axi_limit2(&drv->dev,
-                                AXI_LIMIT2_MAX_BEATS_BYTES,
-                                AXI_LIMIT2_MEM_TYPE,
-                                AXI_LIMIT2_MAX_OUTSTANDING_READS,
-                                AXI_LIMIT2_MAX_OUTSTANDING_WRITES);
-    (void)ethosu_set_axi_limit3(&drv->dev,
-                                AXI_LIMIT3_MAX_BEATS_BYTES,
-                                AXI_LIMIT3_MEM_TYPE,
-                                AXI_LIMIT3_MAX_OUTSTANDING_READS,
-                                AXI_LIMIT3_MAX_OUTSTANDING_WRITES);
-}
-
-/* Default implementation to flush the data cache. Override if available on the targeted device.
- * Passing NULL as p argument expects the whole cache to be flushed.
- */
-void __attribute__((weak)) ethosu_flush_dcache(uint32_t *p, size_t bytes)
-{
-    (void)p;
-    (void)bytes;
-}
-
-/* Default implementation to invalidate the data cache. Override if available on the targeted device.
- * Passing NULL as p argument expects the whole cache to be flushed.
- */
-void __attribute__((weak)) ethosu_invalidate_dcache(uint32_t *p, size_t bytes)
-{
-    (void)p;
-    (void)bytes;
-}
-
 static int handle_command_stream(struct ethosu_driver *drv,
                                  const uint8_t *cmd_stream,
                                  const int cms_length,
@@ -833,11 +462,11 @@ static int handle_command_stream(struct ethosu_driver *drv,
     uint32_t cms_bytes       = cms_length * BYTES_IN_32_BITS;
     ptrdiff_t cmd_stream_ptr = (ptrdiff_t)cmd_stream;
 
-    LOG_INFO("handle_command_stream: cmd_stream=%p, cms_length %d\n", cmd_stream, cms_length);
+    LOG_INFO("handle_command_stream: cmd_stream=%p, cms_length %d", cmd_stream, cms_length);
 
     if (0 != ((ptrdiff_t)cmd_stream & MASK_16_BYTE_ALIGN))
     {
-        LOG_ERR("Error: Command stream addr %p not aligned to 16 bytes\n", cmd_stream);
+        LOG_ERR("Command stream addr %p not aligned to 16 bytes", cmd_stream);
         return -1;
     }
 
@@ -846,7 +475,7 @@ static int handle_command_stream(struct ethosu_driver *drv,
     {
         if (0 != (base_addr[i] & MASK_16_BYTE_ALIGN))
         {
-            LOG_ERR("Error: Base addr %d: 0x%llx not aligned to 16 bytes\n", i, base_addr[i]);
+            LOG_ERR("Base addr %d: 0x%llx not aligned to 16 bytes", i, base_addr[i]);
             base_addr_invalid = true;
         }
     }
@@ -875,7 +504,7 @@ static int handle_command_stream(struct ethosu_driver *drv,
         ethosu_flush_dcache(NULL, 0);
     }
 
-    if (ETHOSU_SUCCESS != ethosu_run_command_stream(&drv->dev, cmd_stream, cms_bytes, base_addr, num_base_addr))
+    if (ETHOSU_SUCCESS != ethosu_dev_run_command_stream(&drv->dev, cmd_stream, cms_bytes, base_addr, num_base_addr))
     {
         return -1;
     }
@@ -899,11 +528,10 @@ static int handle_command_stream(struct ethosu_driver *drv,
         ethosu_invalidate_dcache(NULL, 0);
     }
 
-    (void)ethosu_get_qread(&drv->dev, &qread);
+    qread = ethosu_dev_get_qread(&drv->dev);
     if (qread != cms_bytes)
     {
-        LOG_WARN(
-            "Failure: IRQ received but qread (%" PRIu32 ") not at end of stream (%" PRIu32 ").\n", qread, cms_bytes);
+        LOG_WARN("IRQ received but qread (%" PRIu32 ") not at end of stream (%" PRIu32 ").", qread, cms_bytes);
         return -1;
     }
 
@@ -919,16 +547,16 @@ static int read_apb_reg(struct ethosu_driver *drv, uint16_t da_data)
     reg_p = (uint32_t *)malloc(num_reg * sizeof(uint32_t));
     if (reg_p == NULL)
     {
-        LOG_INFO("read_apb_reg, Error! memory not allocated.");
+        LOG_ERR("Memory allocation failed");
         return -1;
     }
 
-    if (ETHOSU_SUCCESS == ethosu_read_apb_reg(&drv->dev, start_address, num_reg, reg_p))
+    if (ETHOSU_SUCCESS == ethosu_dev_read_apb_reg(&drv->dev, start_address, num_reg, reg_p))
     {
         for (int i = 0; i < num_reg; i++)
         {
             LOG_INFO(
-                "NPU_REG ADDR 0x%04" PRIu32 " = 0x%08" PRIu32 "\n", (start_address + (i * BYTES_IN_32_BITS)), reg_p[i]);
+                "NPU_REG ADDR 0x%04" PRIu32 " = 0x%08" PRIu32 "", (start_address + (i * BYTES_IN_32_BITS)), reg_p[i]);
         }
     }
     else
@@ -945,25 +573,25 @@ static int dump_shram(struct ethosu_driver *drv)
 {
     struct ethosu_config cfg;
     uint32_t *shram_p;
-    (void)ethosu_get_config(&drv->dev, &cfg);
+    (void)ethosu_dev_get_config(&drv->dev, &cfg);
 
-    LOG_INFO("dump_shram size = %" PRIu32 " KB\n", cfg.shram_size);
+    LOG_INFO("dump_shram size = %" PRIu32 " KB", cfg.shram_size);
 
     shram_p = (uint32_t *)malloc(BYTES_1KB);
     if (shram_p == NULL)
     {
-        LOG_ERR("read_shram, Error! memory not allocated.");
+        LOG_ERR("Memory allocation failed for shram data");
         return -1;
     }
 
     for (uint32_t i = 0; i < cfg.shram_size; i++)
     {
-        ethosu_get_shram_data(&drv->dev, i, (uint32_t *)shram_p);
+        ethosu_dev_get_shram_data(&drv->dev, i, (uint32_t *)shram_p);
         // Output 1KB of SHRAM
-        LOG_INFO("***SHRAM SECTION %" PRIu32 "***\n", i);
+        LOG_INFO("***SHRAM SECTION %" PRIu32 "***", i);
         for (int j = 0; j < (BYTES_1KB / BYTES_IN_32_BITS); j++)
         {
-            LOG_INFO("[0x%04" PRIx32 "] %" PRIx32 "\n", (i * 1024 + j * 4), shram_p[j]);
+            LOG_INFO("[0x%04" PRIx32 "] %" PRIx32 "", (i * 1024 + j * 4), shram_p[j]);
         }
     }
     free(shram_p);
@@ -971,317 +599,330 @@ static int dump_shram(struct ethosu_driver *drv)
     return 0;
 }
 
-typedef struct
+/******************************************************************************
+ * Weak functions - Interrupt handler
+ ******************************************************************************/
+void __attribute__((weak)) ethosu_irq_handler(struct ethosu_driver *drv)
 {
-    int number;
-    const char *name;
-} name_lookup_t;
-
-static const name_lookup_t npu_reg_name_tbl[] = {
-    {0x200, "KERNEL_X"},
-    {0x204, "KERNEL_Y"},
-    {0x208, "KERNEL_W_M1"},
-    {0x20C, "KERNEL_H_M1"},
-    {0x210, "OFM_CBLK_WIDTH_M1"},
-    {0x214, "OFM_CBLK_HEIGHT_M1"},
-    {0x218, "OFM_CBLK_DEPTH_M1"},
-    {0x21c, "IFM_CBLK_DEPTH_M1"},
-    {0x220, "OFM_X"},
-    {0x224, "OFM_Y"},
-    {0x228, "OFM_Z"},
-    {0x22C, "IFM_Z"},
-    {0x230, "PAD_TOP"},
-    {0x234, "PAD_LEFT"},
-    {0x238, "IFM_CBLK_WIDTH"},
-    {0x23C, "IFM_CBLK_HEIGHT"},
-    {0x240, "DMA_IFM_SRC"},
-    {0x244, "DMA_IFM_SRC_HI"},
-    {0x248, "DMA_IFM_DST"},
-    {0x24c, "DMA_OFM_SRC"},
-    {0x250, "DMA_OFM_DST"},
-    {0x254, "DMA_OFM_DST_HI"},
-    {0x258, "DMA_WEIGHT_SRC"},
-    {0x25c, "DMA_WEIGHT_SRC_HI"},
-    {0x260, "DMA_CMD_SRC"},
-    {0x264, "DMA_CMD_SRC_HI"},
-    {0x268, "DMA_CMD_SIZE"},
-    {0x26c, "DMA_M2M_SRC"},
-    {0x270, "DMA_M2M_SRC_HI"},
-    {0x274, "DMA_M2M_DST"},
-    {0x278, "DMA_M2M_DST_HI"},
-    {0x27c, "CURRENT_QREAD"},
-    {0x280, "DMA_SCALE_SRC"},
-    {0x284, "DMA_SCALE_SRC_HI"},
-    {0x2BC, "CURRENT_CMD"},
-    {0x800, "IFM_PAD_TOP"},
-    {0x804, "IFM_PAD_LEFT"},
-    {0x808, "IFM_PAD_RIGHT"},
-    {0x80C, "IFM_PAD_BOTTOM"},
-    {0x810, "IFM_DEPTH_M1"},
-    {0x814, "IFM_PRECISION"},
-    {0x81C, "IFM_UPSCALE"},
-    {0x824, "IFM_ZERO_POINT"},
-    {0x828, "IFM_WIDTH0_M1"},
-    {0x82C, "IFM_HEIGHT0_M1"},
-    {0x830, "IFM_HEIGHT1_M1"},
-    {0x834, "IFM_IB_END"},
-    {0x83C, "IFM_REGION"},
-    {0x844, "OFM_WIDTH_M1"},
-    {0x848, "OFM_HEIGHT_M1"},
-    {0x84C, "OFM_DEPTH_M1"},
-    {0x850, "OFM_PRECISION"},
-    {0x854, "OFM_BLK_WIDTH_M1"},
-    {0x858, "OFM_BLK_HEIGHT_M1"},
-    {0x85C, "OFM_BLK_DEPTH_M1"},
-    {0x860, "OFM_ZERO_POINT"},
-    {0x868, "OFM_WIDTH0_M1"},
-    {0x86C, "OFM_HEIGHT0_M1"},
-    {0x870, "OFM_HEIGHT1_M1"},
-    {0x87C, "OFM_REGION"},
-    {0x880, "KERNEL_WIDTH_M1"},
-    {0x884, "KERNEL_HEIGHT_M1"},
-    {0x888, "KERNEL_STRIDE"},
-    {0x88C, "PARALLEL_MODE"},
-    {0x890, "ACC_FORMAT"},
-    {0x894, "ACTIVATION"},
-    {0x898, "ACTIVATION_MIN"},
-    {0x89C, "ACTIVATION_MAX"},
-    {0x8A0, "WEIGHT_REGION"},
-    {0x8A4, "SCALE_REGION"},
-    {0x8B4, "AB_START"},
-    {0x8BC, "BLOCKDEP"},
-    {0x8C0, "DMA0_SRC_REGION"},
-    {0x8C4, "DMA0_DST_REGION"},
-    {0x8C8, "DMA0_SIZE0"},
-    {0x8CC, "DMA0_SIZE1"},
-    {0x900, "IFM2_BROADCAST"},
-    {0x904, "IFM2_SCALAR"},
-    {0x924, "IFM2_ZERO_POINT"},
-    {0x928, "IFM2_WIDTH0_M1"},
-    {0x92C, "IFM2_HEIGHT0_M1"},
-    {0x930, "IFM2_HEIGHT1_M1"},
-    {0x934, "IFM2_IB_START"},
-    {0x93C, "IFM2_REGION"},
-    {0xA00, "IFM_BASE0"},
-    {0xA04, "IFM_BASE0_HI"},
-    {0xA08, "IFM_BASE1"},
-    {0xA0C, "IFM_BASE1_HI"},
-    {0xA10, "IFM_BASE2"},
-    {0xA14, "IFM_BASE2_HI"},
-    {0xA18, "IFM_BASE3"},
-    {0xA1C, "IFM_BASE3_HI"},
-    {0xA20, "IFM_STRIDE_X"},
-    {0xA24, "IFM_STRIDE_X_HI"},
-    {0xA28, "IFM_STRIDE_Y"},
-    {0xA2C, "IFM_STRIDE_Y_HI"},
-    {0xA30, "IFM_STRIDE_C"},
-    {0xA34, "IFM_STRIDE_C_HI"},
-    {0xA40, "OFM_BASE0"},
-    {0xA44, "OFM_BASE0_HI"},
-    {0xA48, "OFM_BASE1"},
-    {0xA4C, "OFM_BASE1_HI"},
-    {0xA50, "OFM_BASE2"},
-    {0xA54, "OFM_BASE2_HI"},
-    {0xA58, "OFM_BASE3"},
-    {0xA5C, "OFM_BASE3_HI"},
-    {0xA60, "OFM_STRIDE_X"},
-    {0xA64, "OFM_STRIDE_X_HI"},
-    {0xA68, "OFM_STRIDE_Y"},
-    {0xA6C, "OFM_STRIDE_Y_HI"},
-    {0xA70, "OFM_STRIDE_C"},
-    {0xA74, "OFM_STRIDE_C_HI"},
-    {0xA80, "WEIGHT_BASE"},
-    {0xA84, "WEIGHT_BASE_HI"},
-    {0xA88, "WEIGHT_LENGTH"},
-    {0xA8C, "WEIGHT_LENGTH_HI"},
-    {0xA90, "SCALE_BASE"},
-    {0xA94, "SCALE_BASE_HI"},
-    {0xA98, "SCALE_LENGTH"},
-    {0xAA0, "OFM_SCALE"},
-    {0xAA4, "OFM_SCALE_SHIFT"},
-    {0xAA8, "OPA_SCALE "},
-    {0xAB0, "OPB_SCALE"},
-    {0xAC0, "DMA0_SRC"},
-    {0xAC4, "DMA0_SRC_HI"},
-    {0xAC8, "DMA0_DST"},
-    {0xACC, "DMA0_DST_HI"},
-    {0xAD0, "DMA0_LEN"},
-    {0xAD4, "DMA0_LEN_HI"},
-    {0xAD8, "DMA0_SKIP0"},
-    {0xADC, "DMA0_SKIP0_HI"},
-    {0xAE0, "DMA0_SKIP1"},
-    {0xAE4, "DMA0_SKIP1_HI"},
-    {0xB00, "IFM2_BASE0"},
-    {0xB04, "IFM2_BASE0_HI"},
-    {0xB08, "IFM2_BASE1"},
-    {0xB0C, "IFM2_BASE1_HI"},
-    {0xB10, "IFM2_BASE2"},
-    {0xB14, "IFM2_BASE2_HI"},
-    {0xB18, "IFM2_BASE3"},
-    {0xB1C, "IFM2_BASE3_HI"},
-    {0xB20, "IFM2_STRIDE_X"},
-    {0xB24, "IFM2_STRIDE_X_HI"},
-    {0xB28, "IFM2_STRIDE_Y"},
-    {0xB2C, "IFM2_STRIDE_Y_HI"},
-    {0xB30, "IFM2_STRIDE_C"},
-    {0xB34, "IFM2_STRIDE_C_HI"},
-    {0xB40, "WEIGHT1_BASE"},
-    {0xB44, "WEIGHT1_BASE_HI"},
-    {0xB48, "WEIGHT1_LENGTH"},
-    {0xB4C, "WEIGHT1_LENGTH_HI"},
-    {0xB50, "SCALE1_BASE"},
-    {0xB54, "SCALE1_BASE_HI"},
-    {0xB58, "SCALE1_LENGTH"},
-};
+    uint8_t irq_raised = 0;
 
-static const char *lookup_name(const name_lookup_t *lookup_table, int lookup_table_count, int find)
-{
-    int n;
-    for (n = 0; n < lookup_table_count; n++)
+    LOG_DEBUG("Interrupt. status=0x%08x, qread=%d", ethosu_dev_get_status(&drv->dev), ethosu_dev_get_qread(&drv->dev));
+
+    // Verify that interrupt has been raised
+    (void)ethosu_dev_is_irq_raised(&drv->dev, &irq_raised);
+    assert(irq_raised == 1);
+    drv->irq_triggered = true;
+
+    // Clear interrupt
+    (void)ethosu_dev_clear_irq_status(&drv->dev);
+
+    // Verify that interrupt has been successfully cleared
+    (void)ethosu_dev_is_irq_raised(&drv->dev, &irq_raised);
+    assert(irq_raised == 0);
+
+    if (ethosu_dev_status_has_error(&drv->dev))
     {
-        if (lookup_table[n].number == find)
-        {
-            return lookup_table[n].name;
-        }
+        ethosu_soft_reset_and_restore(drv);
+        drv->status_error = true;
     }
-    // Not found
-    return 0;
+
+    ethosu_semaphore_give(drv->semaphore);
 }
 
-static void dump_npu_register(struct ethosu_driver *drv, int npu_reg, int npu_reg_end)
+/******************************************************************************
+ * Functions API
+ ******************************************************************************/
+
+int ethosu_init(struct ethosu_driver *drv,
+                const void *base_address,
+                const void *fast_memory,
+                const size_t fast_memory_size,
+                uint32_t secure_enable,
+                uint32_t privilege_enable)
 {
-    unsigned int reg_val;
-    const char *reg_name;
-    int npu_reg_name_tbl_count = sizeof(npu_reg_name_tbl) / sizeof(npu_reg_name_tbl[0]);
+    int return_code = 0;
+
+    LOG_INFO("Initializing NPU: base_address=%p, fast_memory=%p, fast_memory_size=%zu, secure=%" PRIu32
+             ", privileged=%" PRIu32,
+             base_address,
+             fast_memory,
+             fast_memory_size,
+             secure_enable,
+             privilege_enable);
+
+    if (!ethosu_mutex)
+    {
+        ethosu_mutex = ethosu_mutex_create();
+    }
 
-    LOG_INFO("dump_register %X - %X\n", npu_reg, npu_reg_end);
-    for (; npu_reg <= npu_reg_end; npu_reg += sizeof(int))
+    if (!ethosu_semaphore)
     {
-        reg_val  = ethosu_read_reg(&drv->dev, npu_reg);
-        reg_name = lookup_name(npu_reg_name_tbl, npu_reg_name_tbl_count, npu_reg);
-        LOG_INFO("[0x%.4X] 0x%.8X\t%s\n", npu_reg, reg_val, (reg_name) ? reg_name : "");
+        ethosu_semaphore = ethosu_semaphore_create();
     }
+
+    drv->fast_memory      = (uint32_t)fast_memory;
+    drv->fast_memory_size = fast_memory_size;
+    drv->irq_triggered    = false;
+    drv->semaphore        = ethosu_semaphore_create();
+
+    if (ETHOSU_SUCCESS != ethosu_dev_init(&drv->dev, base_address, secure_enable, privilege_enable))
+    {
+        LOG_ERR("Failed to initialize Ethos-U device");
+        return -1;
+    }
+
+    if (ETHOSU_SUCCESS !=
+        set_clock_and_power_request(drv, ETHOSU_INFERENCE_REQUEST, ETHOSU_CLOCK_Q_DISABLE, ETHOSU_POWER_Q_DISABLE))
+    {
+        LOG_ERR("Failed to disable clock-q & power-q for Ethos-U");
+        return -1;
+    }
+
+    if (ETHOSU_SUCCESS != ethosu_dev_soft_reset(&drv->dev))
+    {
+        return -1;
+    }
+
+    if (ETHOSU_SUCCESS != ethosu_dev_wait_for_reset(&drv->dev))
+    {
+        LOG_ERR("Failed reset of Ethos-U");
+        return -1;
+    }
+
+    drv->status_error = false;
+
+    ethosu_register_driver(drv);
+
+    return return_code;
 }
 
-static const name_lookup_t cmd0_name_tbl[] = {
-    {0x000, "NPU_OP_STOP"},
-    {0x001, "NPU_OP_IRQ"},
-    {0x002, "NPU_OP_CONV"},
-    {0x003, "NPU_OP_DEPTHWISE"},
-    {0x004, "NPU_OP_VECTOR_PROD"},
-    {0x005, "NPU_OP_POOL"},
-    {0x006, "NPU_OP_ELEMENTWISE"},
-    {0x010, "NPU_OP_DMA_START"},
-    {0x011, "NPU_OP_DMA_WAIT"},
-    {0x012, "NPU_OP_KERNEL_WAIT"},
-    {0x100, "NPU_SET_IFM_PAD_TOP"},
-    {0x101, "NPU_SET_IFM_PAD_LEFT"},
-    {0x102, "NPU_SET_IFM_PAD_RIGHT"},
-    {0x103, "NPU_SET_IFM_PAD_BOTTOM"},
-    {0x104, "NPU_SET_IFM_DEPTH_M1"},
-    {0x105, "NPU_SET_IFM_PRECISION"},
-    {0x107, "NPU_SET_IFM_UPSCALE"},
-    {0x109, "NPU_SET_IFM_ZERO_POINT"},
-    {0x10A, "NPU_SET_IFM_WIDTH0_M1"},
-    {0x10B, "NPU_SET_IFM_HEIGHT0_M1"},
-    {0x10C, "NPU_SET_IFM_HEIGHT1_M1"},
-    {0x10D, "NPU_SET_IFM_IB_END"},
-    {0x10F, "NPU_SET_IFM_REGION"},
-    {0x110, "NPU_SET_OFM_BATCH_SIZE_M1"},
-    {0x111, "NPU_SET_OFM_WIDTH_M1"},
-    {0x112, "NPU_SET_OFM_HEIGHT_M1"},
-    {0x113, "NPU_SET_OFM_DEPTH_M1"},
-    {0x114, "NPU_SET_OFM_PRECISION"},
-    {0x115, "NPU_SET_OFM_BLK_WIDTH_M1"},
-    {0x116, "NPU_SET_OFM_BLK_HEIGHT_M1"},
-    {0x117, "NPU_SET_OFM_BLK_DEPTH_M1"},
-    {0x118, "NPU_SET_OFM_ZERO_POINT"},
-    {0x11A, "NPU_SET_OFM_WIDTH0_M1"},
-    {0x11B, "NPU_SET_OFM_HEIGHT0_M1"},
-    {0x11C, "NPU_SET_OFM_HEIGHT1_M1"},
-    {0x11F, "NPU_SET_OFM_REGION"},
-    {0x120, "NPU_SET_KERNEL_WIDTH_M1"},
-    {0x121, "NPU_SET_KERNEL_HEIGHT_M1"},
-    {0x122, "NPU_SET_KERNEL_STRIDE"},
-    {0x124, "NPU_SET_ACC_FORMAT"},
-    {0x125, "NPU_SET_ACTIVATION"},
-    {0x126, "NPU_SET_ACTIVATION_MIN"},
-    {0x127, "NPU_SET_ACTIVATION_MAX"},
-    {0x128, "NPU_SET_WEIGHT_REGION"},
-    {0x129, "NPU_SET_SCALE_REGION"},
-    {0x12D, "NPU_SET_AB_START"},
-    {0x12F, "NPU_SET_BLOCKDEP"},
-    {0x130, "NPU_SET_DMA0_SRC_REGION"},
-    {0x131, "NPU_SET_DMA0_DST_REGION"},
-    {0x180, "NPU_SET_IFM2_BROADCAST"},
-    {0x181, "NPU_SET_IFM2_SCALAR"},
-    {0x185, "NPU_SET_IFM2_PRECISION"},
-    {0x189, "NPU_SET_IFM2_ZERO_POINT"},
-    {0x18A, "NPU_SET_IFM2_WIDTH0_M1"},
-    {0x18B, "NPU_SET_IFM2_HEIGHT0_M1"},
-    {0x18C, "NPU_SET_IFM2_HEIGHT1_M1"},
-    {0x18D, "NPU_SET_IFM2_IB_START"},
-    {0x18F, "NPU_SET_IFM2_REGION"},
-};
+void ethosu_get_driver_version(struct ethosu_driver_version *ver)
+{
+    assert(ver != NULL);
+    ver->major = ETHOSU_DRIVER_VERSION_MAJOR;
+    ver->minor = ETHOSU_DRIVER_VERSION_MINOR;
+    ver->patch = ETHOSU_DRIVER_VERSION_PATCH;
+}
 
-static const name_lookup_t cmd1_name_tbl[] = {
-    {0x000, "NPU_SET_IFM_BASE0"},     {0x001, "NPU_SET_IFM_BASE1"},     {0x002, "NPU_SET_IFM_BASE2"},
-    {0x003, "NPU_SET_IFM_BASE3"},     {0x004, "NPU_SET_IFM_STRIDE_X"},  {0x005, "NPU_SET_IFM_STRIDE_Y"},
-    {0x006, "NPU_SET_IFM_STRIDE_C"},  {0x007, "NPU_SET_IFM_STRIDE_N"},  {0x010, "NPU_SET_OFM_BASE0"},
-    {0x011, "NPU_SET_OFM_BASE1"},     {0x012, "NPU_SET_OFM_BASE2"},     {0x013, "NPU_SET_OFM_BASE3"},
-    {0x014, "NPU_SET_OFM_STRIDE_X"},  {0x015, "NPU_SET_OFM_STRIDE_Y"},  {0x016, "NPU_SET_OFM_STRIDE_C"},
-    {0x017, "NPU_SET_OFM_STRIDE_N"},  {0x020, "NPU_SET_WEIGHT_BASE"},   {0x021, "NPU_SET_WEIGHT_LENGTH"},
-    {0x022, "NPU_SET_SCALE_BASE"},    {0x023, "NPU_SET_SCALE_LENGTH"},  {0x024, "NPU_SET_OFM_SCALE"},
-    {0x025, "NPU_SET_OPA_SCALE"},     {0x026, "NPU_SET_OPB_SCALE"},     {0x030, "NPU_SET_DMA0_SRC"},
-    {0x031, "NPU_SET_DMA0_DST"},      {0x032, "NPU_SET_DMA0_LEN"},      {0x080, "NPU_SET_IFM2_BASE0"},
-    {0x081, "NPU_SET_IFM2_BASE1"},    {0x082, "NPU_SET_IFM2_BASE2"},    {0x083, "NPU_SET_IFM2_BASE3"},
-    {0x084, "NPU_SET_IFM2_STRIDE_X"}, {0x085, "NPU_SET_IFM2_STRIDE_Y"}, {0x086, "NPU_SET_IFM2_STRIDE_C"},
-};
+void ethosu_get_hw_info(struct ethosu_driver *drv, struct ethosu_hw_info *hw)
+{
+    assert(hw != NULL);
 
-static void dump_command_stream(const uint32_t *cmd_stream, const int cms_length, int qread)
+    (void)ethosu_dev_get_id(&drv->dev, &hw->version);
+    (void)ethosu_dev_get_config(&drv->dev, &hw->cfg);
+}
+
+int ethosu_invoke(struct ethosu_driver *drv,
+                  const void *custom_data_ptr,
+                  const int custom_data_size,
+                  const uint64_t *base_addr,
+                  const size_t *base_addr_size,
+                  const int num_base_addr)
 {
-    int n;
-    int offset;
-    uint32_t cmd_val;
-    const uint8_t *cmd_ptr;
-    const char *cmd_name;
-    int cmd0_name_tbl_count = sizeof(cmd0_name_tbl) / sizeof(cmd0_name_tbl[0]);
-    int cmd1_name_tbl_count = sizeof(cmd1_name_tbl) / sizeof(cmd1_name_tbl[0]);
-
-    LOG_INFO("dump_command_stream cmd_stream = 0x%8p cms_length = %d\n", cmd_stream, cms_length);
-    for (n = 0; n < cms_length; n++)
+    const struct custom_data_s *data_ptr = custom_data_ptr;
+    const struct custom_data_s *data_end = custom_data_ptr + custom_data_size;
+    int return_code                      = 0;
+
+    // First word in custom_data_ptr should contain "Custom Operator Payload 1"
+    if (data_ptr->word != ETHOSU_FOURCC)
+    {
+        LOG_ERR("Custom Operator Payload: %" PRIu32 " is not correct, expected %x", data_ptr->word, ETHOSU_FOURCC);
+        return -1;
+    }
+
+    // Custom data length must be a multiple of 32 bits
+    if ((custom_data_size % BYTES_IN_32_BITS) != 0)
     {
-        // Offset
-        offset = n * sizeof(int);
-        LOG_INFO("[%.4d] ", offset);
-        // Command
-        cmd_ptr = (const uint8_t *)&cmd_stream[n];
-        LOG_INFO("0x%.2X 0x%.2X 0x%.2X 0x%.2X ", cmd_ptr[0], cmd_ptr[1], cmd_ptr[2], cmd_ptr[3]);
-        // Command name and payload
-        if (cmd_stream[n] & 0x4000)
+        LOG_ERR("custom_data_size=0x%x not a multiple of 4", custom_data_size);
+        return -1;
+    }
+
+    ++data_ptr;
+
+    // Adjust base address to fast memory area
+    if (drv->fast_memory != 0 && num_base_addr >= FAST_MEMORY_BASE_ADDR_INDEX)
+    {
+        uint64_t *fast_memory = (uint64_t *)&base_addr[FAST_MEMORY_BASE_ADDR_INDEX];
+
+        if (base_addr_size != NULL && base_addr_size[FAST_MEMORY_BASE_ADDR_INDEX] > drv->fast_memory_size)
         {
-            cmd_name = lookup_name(cmd1_name_tbl, cmd1_name_tbl_count, cmd_stream[n] & 0x3FF);
-            n++;
-            cmd_val = cmd_stream[n];
-            cmd_ptr = (const uint8_t *)&cmd_stream[n];
-            LOG_INFO("0x%.2X 0x%.2X 0x%.2X 0x%.2X ", cmd_ptr[0], cmd_ptr[1], cmd_ptr[2], cmd_ptr[3]);
+            LOG_ERR("Fast memory area too small. fast_memory_size=%u, base_addr_size=%u",
+                    drv->fast_memory_size,
+                    base_addr_size[FAST_MEMORY_BASE_ADDR_INDEX]);
+            return -1;
         }
-        else
+
+        *fast_memory = drv->fast_memory;
+    }
+
+    if (!drv->dev_power_always_on)
+    {
+        // Only soft reset if security state or privilege level needs changing
+        if (ethosu_dev_prot_has_changed(&drv->dev))
         {
-            cmd_val  = cmd_stream[n] >> 16;
-            cmd_name = lookup_name(cmd0_name_tbl, cmd0_name_tbl_count, cmd_stream[n] & 0x3FF);
+            if (ETHOSU_SUCCESS != ethosu_dev_soft_reset(&drv->dev))
+            {
+                return -1;
+            }
         }
-        if (cmd_name)
+
+        drv->status_error = false;
+        set_clock_and_power_request(drv, ETHOSU_INFERENCE_REQUEST, ETHOSU_CLOCK_Q_ENABLE, ETHOSU_POWER_Q_DISABLE);
+        ethosu_dev_restore_pmu_config(&drv->dev);
+        npu_axi_init(drv);
+    }
+
+    drv->status_error = false;
+
+    ethosu_inference_begin(drv, custom_data_ptr);
+    while (data_ptr < data_end)
+    {
+        int ret = 0;
+        switch (data_ptr->driver_action_command)
         {
-            LOG_INFO("\t%s 0x%.8" PRIX32, cmd_name, cmd_val);
+        case OPTIMIZER_CONFIG:
+            LOG_DEBUG("OPTIMIZER_CONFIG");
+            struct opt_cfg_s *opt_cfg_p = (struct opt_cfg_s *)data_ptr;
+
+            ret = handle_optimizer_config(drv, opt_cfg_p);
+            data_ptr += DRIVER_ACTION_LENGTH_32_BIT_WORD + OPTIMIZER_CONFIG_LENGTH_32_BIT_WORD;
+            break;
+        case COMMAND_STREAM:
+            LOG_DEBUG("COMMAND_STREAM");
+            void *command_stream = (uint8_t *)(data_ptr) + sizeof(struct custom_data_s);
+            int cms_length       = (data_ptr->reserved << 16) | data_ptr->length;
+
+            drv->abort_inference = false;
+            // It is safe to clear this flag without atomic, because npu is not running.
+            drv->irq_triggered = false;
+
+            ret = handle_command_stream(drv, command_stream, cms_length, base_addr, base_addr_size, num_base_addr);
+
+            if (return_code == -1 && drv->abort_inference)
+            {
+                LOG_ERR("NPU timeout. qread=%" PRIu32, ethosu_dev_get_qread(&drv->dev));
+                dump_shram(drv);
+            }
+
+            data_ptr += DRIVER_ACTION_LENGTH_32_BIT_WORD + cms_length;
+            break;
+        case READ_APB_REG:
+            LOG_DEBUG("READ_APB_REG");
+            ret = read_apb_reg(drv, data_ptr->driver_action_data);
+            data_ptr += DRIVER_ACTION_LENGTH_32_BIT_WORD;
+            break;
+        case DUMP_SHRAM:
+            LOG_DEBUG("DUMP_SHRAM");
+            ret = dump_shram(drv);
+            data_ptr += DRIVER_ACTION_LENGTH_32_BIT_WORD;
+            break;
+        case NOP:
+            LOG_DEBUG("NOP");
+            data_ptr += DRIVER_ACTION_LENGTH_32_BIT_WORD;
+            break;
+        default:
+            LOG_ERR("UNSUPPORTED driver_action_command: %d ", data_ptr->driver_action_command);
+            ret = -1;
+            break;
         }
-        if (offset == qread)
+        if (ret != 0)
         {
-            LOG_INFO(" <<== QREAD\n");
+            return_code = -1;
+            break;
         }
-        else
+    }
+    ethosu_inference_end(drv, custom_data_ptr);
+
+    if (!drv->status_error && !drv->dev_power_always_on)
+    {
+        ethosu_dev_save_pmu_counters(&drv->dev);
+        set_clock_and_power_request(drv, ETHOSU_INFERENCE_REQUEST, ETHOSU_CLOCK_Q_ENABLE, ETHOSU_POWER_Q_ENABLE);
+    }
+
+    return return_code;
+}
+
+void ethosu_abort(struct ethosu_driver *drv)
+{
+    drv->abort_inference = true;
+}
+
+void ethosu_set_power_mode(struct ethosu_driver *drv, bool always_on)
+{
+    drv->dev_power_always_on = always_on;
+
+    if (always_on)
+    {
+        npu_axi_init(drv);
+    }
+}
+
+struct ethosu_driver *ethosu_reserve_driver(void)
+{
+    struct ethosu_driver *drv = NULL;
+
+    do
+    {
+        ethosu_mutex_lock(ethosu_mutex);
+        drv = ethosu_find_and_reserve_driver();
+        ethosu_mutex_unlock(ethosu_mutex);
+
+        if (drv != NULL)
         {
-            LOG_INFO("\n");
+            break;
         }
+
+        LOG_INFO("Waiting for NPU driver handle to become available...");
+        ethosu_semaphore_take(ethosu_semaphore);
+
+    } while (1);
+
+    return drv;
+}
+
+void ethosu_release_driver(struct ethosu_driver *drv)
+{
+    ethosu_mutex_lock(ethosu_mutex);
+    if (drv != NULL && drv->reserved)
+    {
+        drv->reserved = false;
+        LOG_DEBUG("NPU driver handle %p released", drv);
+        ethosu_semaphore_give(ethosu_semaphore);
+    }
+    ethosu_mutex_unlock(ethosu_mutex);
+}
+
+enum ethosu_error_codes set_clock_and_power_request(struct ethosu_driver *drv,
+                                                    enum ethosu_request_clients client,
+                                                    enum ethosu_clock_q_request clock_request,
+                                                    enum ethosu_power_q_request power_request)
+{
+    // Set clock request bit for client
+    if (clock_request == ETHOSU_CLOCK_Q_DISABLE)
+    {
+        drv->clock_request |= (1 << client);
+    }
+    else
+    {
+        drv->clock_request &= ~(1 << client);
+    }
+    // Get current clock request (ENABLE if both PMU and INFERENCE asks for clock request, else DISABLE)
+    clock_request = drv->clock_request == 0 ? ETHOSU_CLOCK_Q_ENABLE : ETHOSU_CLOCK_Q_DISABLE;
+
+    // Set power request bit for client
+    if (power_request == ETHOSU_POWER_Q_DISABLE)
+    {
+        drv->power_request |= (1 << client);
     }
+    else
+    {
+        drv->power_request &= ~(1 << client);
+    }
+    // Get current power request (ENABLE if both PMU and INFERENCE asks for power request, else DISABLE)
+    power_request = drv->power_request == 0 ? ETHOSU_POWER_Q_ENABLE : ETHOSU_POWER_Q_DISABLE;
+
+    // Set clock and power
+    enum ethosu_error_codes ret = ethosu_dev_set_clock_and_power(&drv->dev, clock_request, power_request);
+
+    return ret;
 }
diff --git a/src/ethosu_pmu.c b/src/ethosu_pmu.c
index 5872d18..52aa393 100644
--- a/src/ethosu_pmu.c
+++ b/src/ethosu_pmu.c
@@ -91,7 +91,7 @@ void ETHOSU_PMU_Enable(struct ethosu_driver *drv)
     pmcr.word   = drv->dev.pmcr;
     pmcr.cnt_en = 1;
     set_clock_and_power_request(drv, ETHOSU_PMU_REQUEST, ETHOSU_CLOCK_Q_DISABLE, ETHOSU_POWER_Q_DISABLE);
-    ethosu_write_reg_shadow(&drv->dev, NPU_REG_PMCR, pmcr.word, &drv->dev.pmcr);
+    ethosu_dev_write_reg_shadow(&drv->dev, NPU_REG_PMCR, pmcr.word, &drv->dev.pmcr);
 }
 
 void ETHOSU_PMU_Disable(struct ethosu_driver *drv)
@@ -101,7 +101,7 @@ void ETHOSU_PMU_Disable(struct ethosu_driver *drv)
     pmcr.word   = drv->dev.pmcr;
     pmcr.cnt_en = 0;
     set_clock_and_power_request(drv, ETHOSU_PMU_REQUEST, ETHOSU_CLOCK_Q_ENABLE, ETHOSU_POWER_Q_ENABLE);
-    ethosu_write_reg_shadow(&drv->dev, NPU_REG_PMCR, pmcr.word, &drv->dev.pmcr);
+    ethosu_dev_write_reg_shadow(&drv->dev, NPU_REG_PMCR, pmcr.word, &drv->dev.pmcr);
 }
 
 void ETHOSU_PMU_Set_EVTYPER(struct ethosu_driver *drv, uint32_t num, enum ethosu_pmu_event_type type)
@@ -109,7 +109,7 @@ void ETHOSU_PMU_Set_EVTYPER(struct ethosu_driver *drv, uint32_t num, enum ethosu
     assert(num < ETHOSU_PMU_NCOUNTERS);
     uint32_t val = pmu_event_value(type);
     LOG_DEBUG("%s: num=%u, type=%d, val=%u\n", __FUNCTION__, num, type, val);
-    ethosu_write_reg_shadow(&drv->dev, NPU_REG_PMEVTYPER(num), val, &drv->dev.pmu_evtypr[num]);
+    ethosu_dev_write_reg_shadow(&drv->dev, NPU_REG_PMEVTYPER(num), val, &drv->dev.pmu_evtypr[num]);
 }
 
 enum ethosu_pmu_event_type ETHOSU_PMU_Get_EVTYPER(struct ethosu_driver *drv, uint32_t num)
@@ -127,7 +127,7 @@ void ETHOSU_PMU_CYCCNT_Reset(struct ethosu_driver *drv)
     struct pmcr_r pmcr;
     pmcr.word          = drv->dev.pmcr;
     pmcr.cycle_cnt_rst = 1;
-    ethosu_write_reg_shadow(&drv->dev, NPU_REG_PMCR, pmcr.word, &drv->dev.pmcr);
+    ethosu_dev_write_reg_shadow(&drv->dev, NPU_REG_PMCR, pmcr.word, &drv->dev.pmcr);
     drv->dev.pmccntr[0] = 0;
     drv->dev.pmccntr[1] = 0;
 }
@@ -138,7 +138,7 @@ void ETHOSU_PMU_EVCNTR_ALL_Reset(struct ethosu_driver *drv)
     struct pmcr_r pmcr;
     pmcr.word          = drv->dev.pmcr;
     pmcr.event_cnt_rst = 1;
-    ethosu_write_reg_shadow(&drv->dev, NPU_REG_PMCR, pmcr.word, &drv->dev.pmcr);
+    ethosu_dev_write_reg_shadow(&drv->dev, NPU_REG_PMCR, pmcr.word, &drv->dev.pmcr);
 
     for (uint32_t i = 0; i < ETHOSU_PMU_NCOUNTERS; i++)
     {
@@ -149,13 +149,13 @@ void ETHOSU_PMU_EVCNTR_ALL_Reset(struct ethosu_driver *drv)
 void ETHOSU_PMU_CNTR_Enable(struct ethosu_driver *drv, uint32_t mask)
 {
     LOG_DEBUG("%s: mask=0x%08x\n", __FUNCTION__, mask);
-    ethosu_write_reg_shadow(&drv->dev, NPU_REG_PMCNTENSET, mask, &drv->dev.pmcnten);
+    ethosu_dev_write_reg_shadow(&drv->dev, NPU_REG_PMCNTENSET, mask, &drv->dev.pmcnten);
 }
 
 void ETHOSU_PMU_CNTR_Disable(struct ethosu_driver *drv, uint32_t mask)
 {
     LOG_DEBUG("%s: mask=0x%08x\n", __FUNCTION__, mask);
-    ethosu_write_reg_shadow(&drv->dev, NPU_REG_PMCNTENCLR, mask, &drv->dev.pmcnten);
+    ethosu_dev_write_reg_shadow(&drv->dev, NPU_REG_PMCNTENCLR, mask, &drv->dev.pmcnten);
 }
 
 uint32_t ETHOSU_PMU_CNTR_Status(struct ethosu_driver *drv)
@@ -166,8 +166,8 @@ uint32_t ETHOSU_PMU_CNTR_Status(struct ethosu_driver *drv)
 
 uint64_t ETHOSU_PMU_Get_CCNTR(struct ethosu_driver *drv)
 {
-    uint32_t val_lo = ethosu_read_reg(&drv->dev, NPU_REG_PMCCNTR_LO);
-    uint32_t val_hi = ethosu_read_reg(&drv->dev, NPU_REG_PMCCNTR_HI);
+    uint32_t val_lo = ethosu_dev_read_reg(&drv->dev, NPU_REG_PMCCNTR_LO);
+    uint32_t val_hi = ethosu_dev_read_reg(&drv->dev, NPU_REG_PMCCNTR_HI);
     uint64_t val    = ((uint64_t)val_hi << 32) | val_lo;
     uint64_t shadow = ((uint64_t)drv->dev.pmccntr[1] << 32) | drv->dev.pmccntr[0];
 
@@ -197,8 +197,8 @@ void ETHOSU_PMU_Set_CCNTR(struct ethosu_driver *drv, uint64_t val)
         ETHOSU_PMU_CNTR_Disable(drv, ETHOSU_PMU_CCNT_Msk);
     }
 
-    ethosu_write_reg_shadow(&drv->dev, NPU_REG_PMCCNTR_LO, val & MASK_0_31_BITS, &drv->dev.pmccntr[0]);
-    ethosu_write_reg_shadow(&drv->dev, NPU_REG_PMCCNTR_HI, (val & MASK_32_47_BITS) >> 32, &drv->dev.pmccntr[1]);
+    ethosu_dev_write_reg_shadow(&drv->dev, NPU_REG_PMCCNTR_LO, val & MASK_0_31_BITS, &drv->dev.pmccntr[0]);
+    ethosu_dev_write_reg_shadow(&drv->dev, NPU_REG_PMCCNTR_HI, (val & MASK_32_47_BITS) >> 32, &drv->dev.pmccntr[1]);
 
     if (active)
     {
@@ -209,7 +209,7 @@ void ETHOSU_PMU_Set_CCNTR(struct ethosu_driver *drv, uint64_t val)
 uint32_t ETHOSU_PMU_Get_EVCNTR(struct ethosu_driver *drv, uint32_t num)
 {
     assert(num < ETHOSU_PMU_NCOUNTERS);
-    uint32_t val = ethosu_read_reg(&drv->dev, NPU_REG_PMEVCNTR(num));
+    uint32_t val = ethosu_dev_read_reg(&drv->dev, NPU_REG_PMEVCNTR(num));
     LOG_DEBUG("%s: num=%u, val=%u, shadow=%u\n", __FUNCTION__, num, val, drv->dev.pmu_evcntr[num]);
 
     // Return the shadow variable in case the NPU was powered off and lost the event count
@@ -228,31 +228,31 @@ void ETHOSU_PMU_Set_EVCNTR(struct ethosu_driver *drv, uint32_t num, uint32_t val
 {
     assert(num < ETHOSU_PMU_NCOUNTERS);
     LOG_DEBUG("%s: num=%u, val=%u\n", __FUNCTION__, num, val);
-    ethosu_write_reg(&drv->dev, NPU_REG_PMEVCNTR(num), val);
+    ethosu_dev_write_reg(&drv->dev, NPU_REG_PMEVCNTR(num), val);
 }
 
 uint32_t ETHOSU_PMU_Get_CNTR_OVS(struct ethosu_driver *drv)
 {
     LOG_DEBUG("%s:\n", __FUNCTION__);
-    return ethosu_read_reg(&drv->dev, NPU_REG_PMOVSSET);
+    return ethosu_dev_read_reg(&drv->dev, NPU_REG_PMOVSSET);
 }
 
 void ETHOSU_PMU_Set_CNTR_OVS(struct ethosu_driver *drv, uint32_t mask)
 {
     LOG_DEBUG("%s:\n", __FUNCTION__);
-    ethosu_write_reg(&drv->dev, NPU_REG_PMOVSCLR, mask);
+    ethosu_dev_write_reg(&drv->dev, NPU_REG_PMOVSCLR, mask);
 }
 
 void ETHOSU_PMU_Set_CNTR_IRQ_Enable(struct ethosu_driver *drv, uint32_t mask)
 {
     LOG_DEBUG("%s: mask=0x%08x\n", __FUNCTION__, mask);
-    ethosu_write_reg_shadow(&drv->dev, NPU_REG_PMINTSET, mask, &drv->dev.pmint);
+    ethosu_dev_write_reg_shadow(&drv->dev, NPU_REG_PMINTSET, mask, &drv->dev.pmint);
 }
 
 void ETHOSU_PMU_Set_CNTR_IRQ_Disable(struct ethosu_driver *drv, uint32_t mask)
 {
     LOG_DEBUG("%s: mask=0x%08x\n", __FUNCTION__, mask);
-    ethosu_write_reg_shadow(&drv->dev, NPU_REG_PMINTCLR, mask, &drv->dev.pmint);
+    ethosu_dev_write_reg_shadow(&drv->dev, NPU_REG_PMINTCLR, mask, &drv->dev.pmint);
 }
 
 uint32_t ETHOSU_PMU_Get_IRQ_Enable(struct ethosu_driver *drv)
@@ -273,8 +273,8 @@ void ETHOSU_PMU_CNTR_Increment(struct ethosu_driver *drv, uint32_t mask)
     if (mask & ETHOSU_PMU_CCNT_Msk)
     {
         uint64_t val = ETHOSU_PMU_Get_CCNTR(drv) + 1;
-        ethosu_write_reg_shadow(&drv->dev, NPU_REG_PMCCNTR_LO, val & MASK_0_31_BITS, &drv->dev.pmccntr[0]);
-        ethosu_write_reg_shadow(&drv->dev, NPU_REG_PMCCNTR_HI, (val & MASK_32_47_BITS) >> 32, &drv->dev.pmccntr[1]);
+        ethosu_dev_write_reg_shadow(&drv->dev, NPU_REG_PMCCNTR_LO, val & MASK_0_31_BITS, &drv->dev.pmccntr[0]);
+        ethosu_dev_write_reg_shadow(&drv->dev, NPU_REG_PMCCNTR_HI, (val & MASK_32_47_BITS) >> 32, &drv->dev.pmccntr[1]);
     }
 
     for (int i = 0; i < ETHOSU_PMU_NCOUNTERS; i++)
@@ -282,7 +282,7 @@ void ETHOSU_PMU_CNTR_Increment(struct ethosu_driver *drv, uint32_t mask)
         if (mask & (1 << i))
         {
             uint32_t val = ETHOSU_PMU_Get_EVCNTR(drv, i);
-            ethosu_write_reg_shadow(&drv->dev, NPU_REG_PMEVCNTR(i), val + 1, &drv->dev.pmu_evcntr[i]);
+            ethosu_dev_write_reg_shadow(&drv->dev, NPU_REG_PMEVCNTR(i), val + 1, &drv->dev.pmu_evcntr[i]);
         }
     }
 
@@ -297,7 +297,7 @@ void ETHOSU_PMU_PMCCNTR_CFG_Set_Start_Event(struct ethosu_driver *drv, enum etho
     struct pmccntr_cfg_r cfg;
     cfg.word                = drv->dev.pmccntr_cfg;
     cfg.CYCLE_CNT_CFG_START = val;
-    ethosu_write_reg_shadow(&drv->dev, NPU_REG_PMCCNTR_CFG, cfg.word, &drv->dev.pmccntr_cfg);
+    ethosu_dev_write_reg_shadow(&drv->dev, NPU_REG_PMCCNTR_CFG, cfg.word, &drv->dev.pmccntr_cfg);
 }
 
 void ETHOSU_PMU_PMCCNTR_CFG_Set_Stop_Event(struct ethosu_driver *drv, enum ethosu_pmu_event_type stop_event)
@@ -307,5 +307,5 @@ void ETHOSU_PMU_PMCCNTR_CFG_Set_Stop_Event(struct ethosu_driver *drv, enum ethos
     struct pmccntr_cfg_r cfg;
     cfg.word               = drv->dev.pmccntr_cfg;
     cfg.CYCLE_CNT_CFG_STOP = val;
-    ethosu_write_reg_shadow(&drv->dev, NPU_REG_PMCCNTR_CFG, cfg.word, &drv->dev.pmccntr_cfg);
+    ethosu_dev_write_reg_shadow(&drv->dev, NPU_REG_PMCCNTR_CFG, cfg.word, &drv->dev.pmccntr_cfg);
 }