Kernel watchdog timeout

Implement kernel watchdog that detects when firmware becomes
unresponsive.

Change-Id: I5c5b58a56a2ce629e1fd7cabae83b61823239ea6

1 files changed, 82 insertions, 0 deletions

diff --git a/kernel/ethosu_watchdog.h b/kernel/ethosu_watchdog.h
new file mode 100644
index 0000000..d288af4
--- /dev/null
+++ b/kernel/ethosu_watchdog.h
@@ -0,0 +1,82 @@
+/*
+ * Copyright (c) 2022 Arm Limited.
+ *
+ * This program is free software and is provided to you under the terms of the
+ * GNU General Public License version 2 as published by the Free Software
+ * Foundation, and any use by you of this program is subject to the terms
+ * of such GNU licence.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
+ *
+ * SPDX-License-Identifier: GPL-2.0-only
+ */
+
+#ifndef ETHOSU_WATCHDOG_H
+#define ETHOSU_WATCHDOG_H
+
+/****************************************************************************
+ * Includes
+ ****************************************************************************/
+
+#include <linux/types.h>
+#include <linux/timer.h>
+#include <linux/workqueue.h>
+
+/****************************************************************************
+ * Types
+ ****************************************************************************/
+
+struct device;
+struct ethosu_watchdog;
+
+typedef void (*ethosu_watchdog_cb)(struct ethosu_watchdog *wdog);
+
+struct ethosu_watchdog {
+	struct device      *dev;
+	ethosu_watchdog_cb callback;
+	struct timer_list  timer;
+	struct work_struct work;
+	atomic_t           refcount;
+};
+
+/****************************************************************************
+ * Functions
+ ****************************************************************************/
+
+/**
+ * ethosu_watchdog_init() - Initialize watchdog
+ *
+ * Return: 0 on success, else error code.
+ */
+int ethosu_watchdog_init(struct ethosu_watchdog *wdog,
+			 struct device *dev,
+			 ethosu_watchdog_cb callback);
+
+/**
+ * ethosu_watchdog_deinit() - Deinitialize watchdog
+ */
+void ethosu_watchdog_deinit(struct ethosu_watchdog *wdog);
+
+/**
+ * ethosu_watchdog_reset() - Reset watchdog
+ */
+int ethosu_watchdog_reset(struct ethosu_watchdog *wdog);
+
+/**
+ * ethosu_watchdog_inc() - Increment reference count
+ */
+void ethosu_watchdog_inc(struct ethosu_watchdog *wdog);
+
+/**
+ * ethosu_watchdog_dec() - Decrement reference count
+ */
+void ethosu_watchdog_dec(struct ethosu_watchdog *wdog);
+
+#endif /* ETHOSU_WATCHDOG_H */