diff options
Diffstat (limited to 'source/hal/components/uart_pl011/uart_pl011.c')
-rw-r--r-- | source/hal/components/uart_pl011/uart_pl011.c | 229 |
1 files changed, 229 insertions, 0 deletions
diff --git a/source/hal/components/uart_pl011/uart_pl011.c b/source/hal/components/uart_pl011/uart_pl011.c new file mode 100644 index 0000000..1cbf70c --- /dev/null +++ b/source/hal/components/uart_pl011/uart_pl011.c @@ -0,0 +1,229 @@ +/* + * Copyright (c) 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 + * + * http://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 "uart_stdout.h" +#include "peripheral_memmap.h" /* peripheral memory map definitions */ + +#include <stdio.h> +#include <stdint.h> + +#define CNTLQ 0x11 +#define CNTLS 0x13 +#define DEL 0x7F +#define BACKSPACE 0x08 +#define CR 0x0D +#define LF 0x0A +#define ESC 0x1B + +#define UARTBASE (PL011_UART0_BASE) + +/*****************************************************************************/ +/* UART Control Register Locations */ +/*****************************************************************************/ +#define UART0_DR *((volatile unsigned *) UARTBASE) +#define UART0_RSR *((volatile unsigned *)(UARTBASE + 0x04)) +#define UART0_ECR *((volatile unsigned *)(UARTBASE + 0x04)) +#define UART0_LCRH *((volatile unsigned *)(UARTBASE + 0x2C)) +#define UART0_LCRM *((volatile unsigned *)(UARTBASE + 0x28)) +#define UART0_LCRL *((volatile unsigned *)(UARTBASE + 0x24)) +#define UART0_CR *((volatile unsigned *)(UARTBASE + 0x30)) +#define UART0_FR *((volatile unsigned *)(UARTBASE + 0x18)) +#define UART0_IIR *((volatile unsigned *)(UARTBASE + 0x1C)) +#define UART0_ICR *((volatile unsigned *)(UARTBASE + 0x44)) + +/*****************************************************************************/ +/* Received Status Register - RSR */ +/*****************************************************************************/ +#define RSR_OVERRUN_ERROR 0x08 +#define RSR_BREAK_ERROR 0x04 +#define RSR_PARITY_ERROR 0x02 +#define RSR_FRAMING_ERROR 0x01 + +/*****************************************************************************/ +/* Line Control High Byte Register - LCRH */ +/*****************************************************************************/ +#define LCRH_WORD_LENGTH_8 0x60 +#define LCRH_WORD_LENGTH_7 0x40 +#define LCRH_WORD_LENGTH_6 0x20 +#define LCRH_WORD_LENGTH_5 0x00 +#define LCRH_FIFO_ENABLED 0x10 +#define LCRH_2_STOP_BITS 0x08 +#define LCRH_EVEN_PARITY 0x04 +#define LCRH_PARITY_ENABLE 0x02 +#define LCRH_SEND_BREAK 0x01 + +/*****************************************************************************/ +/* Line Control Medium Byte Register - LCRM */ +/* This register specifies the high byte of the Baud rate divisor */ +/*****************************************************************************/ +#define LCRM_BAUD_460800 0x00 +#define LCRM_BAUD_230400 0x00 +#define LCRM_BAUD_115200 0x00 +#define LCRM_BAUD_76800 0x00 +#define LCRM_BAUD_57600 0x00 +#define LCRM_BAUD_38400 0x00 +#define LCRM_BAUD_19200 0x00 +#define LCRM_BAUD_14400 0x00 +#define LCRM_BAUD_9600 0x00 +#define LCRM_BAUD_2400 0x01 +#define LCRM_BAUD_1200 0x02 + +/*****************************************************************************/ +/* Line Control Low Byte Register - LCRL */ +/* This register specifies the low byte of the Baud rate divisor */ +/*****************************************************************************/ +#define LCRL_BAUD_460800 0x01 +#define LCRL_BAUD_230400 0x03 +#define LCRL_BAUD_115200 0x07 +#define LCRL_BAUD_76800 0x0B +#define LCRL_BAUD_57600 0x0F +#define LCRL_BAUD_38400 0xC +#define LCRL_BAUD_19200 0x2F +#define LCRL_BAUD_14400 0x3F +#define LCRL_BAUD_9600 0x5F +#define LCRL_BAUD_2400 0x7F +#define LCRL_BAUD_1200 0xFF + +/*****************************************************************************/ +/* Control Register - CR */ +/*****************************************************************************/ +#define CR_LOOP_BACK_EN 0x80 +#define CR_TIMEOUT_INT_EN 0x40 +#define CR_TX_INT_ENABLE 0x100 +#define CR_RX_INT_ENABLE 0x200 +#define CR_MODSTAT_INT_EN 0x08 +#define CR_UART_ENABLE 0x01 + +/*****************************************************************************/ +/* Flag Register - FR */ +/*****************************************************************************/ +#define FR_TX_FIFO_EMPTY 0x80 +#define FR_RX_FIFO_FULL 0x40 +#define FR_TX_FIFO_FULL 0x20 +#define FR_RX_FIFO_EMPTY 0x10 +#define FR_BUSY 0x08 +#define FR_CARRIER_DETECT 0x04 +#define FR_SET_READY 0x02 +#define FR_CLEAR_TO_SEND 0x01 + +/*****************************************************************************/ +/* Interrupt Identification Register - IIR */ +/*****************************************************************************/ +#define IIR_RX_TIME_OUT 0x08 +#define IIR_TX 0x04 +#define IIR_RX 0x02 +#define IIR_MODEM 0x01 + +void UartStdOutInit(void) +{ + /* Disable the serial port while setting the baud rate and word length. */ + UART0_CR = 0; + + /* Clear the receive status register. */ + UART0_ECR = 0; + + /* Set the correct baud rate and word length. */ + UART0_LCRL = LCRL_BAUD_115200; + UART0_LCRM = LCRM_BAUD_115200; + UART0_LCRH = LCRH_WORD_LENGTH_8; + + /* Explicitly disable FIFO's for char mode. */ + UART0_LCRH &= ~LCRH_FIFO_ENABLED; + + /* Enable UART0 (and RX/TX) without interrupts. */ + UART0_CR = CR_UART_ENABLE | CR_TX_INT_ENABLE | CR_RX_INT_ENABLE; +} + +unsigned char UartPutc(unsigned char ch) +{ + if (ch == '\n') { + (void) UartPutc('\r'); + } + while (UART0_FR & FR_TX_FIFO_FULL) + ; + UART0_DR = ch; + + return ch; +} + +unsigned char UartGetc(void) +{ + unsigned char c; + while (UART0_FR & FR_RX_FIFO_EMPTY) + ; + c = UART0_DR; + if (c == '\r') { + c = '\n'; + } + + return c; +} + +bool GetLine (char *lp, unsigned int len) +{ + unsigned int cnt = 0; + char c; + + do { + c = UartGetc(); + switch (c) { + case CNTLQ: /* ignore Control S/Q. */ + case CNTLS: + break; + case BACKSPACE: + case DEL: + if (cnt == 0) { + break; + } + cnt--; /* decrement count. */ + lp--; /* and line pointer. */ + UartPutc (0x08); /* echo backspace. */ + UartPutc (' '); + UartPutc (0x08); + fflush (stdout); + break; + case ESC: + case 0: + *lp = 0; /* ESC - stop editing line. */ + return false; + case CR: /* CR - done, stop editing line. */ + UartPutc (*lp = c); /* Echo and store character. */ + lp++; /* Increment line pointer */ + cnt++; /* and count. */ + c = LF; + UartPutc (*lp = c); /* Echo and store character. */ + fflush (stdout); + lp++; /* Increment line pointer */ + cnt++; /* and count. */ + break; + default: + UartPutc (*lp = c); /* echo and store character. */ + fflush (stdout); + lp++; /* increment line pointer. */ + cnt++; /* and count. */ + break; + } + } while (cnt < len - 2 && c != LF); /* check limit and CR. */ + *lp = 0; /* mark end of string. */ + return true; +} + +__attribute__((noreturn)) void UartEndSimulation(int code) +{ + UartPutc((char) 0x4); // End of simulation + UartPutc((char) code); // Exit code + while(1); +} |