From 742261012c087285309bba34b081caf1c6c6ddab Mon Sep 17 00:00:00 2001 From: Kristofer Jonsson Date: Wed, 25 May 2022 16:55:24 +0200 Subject: Documenting porting guidelines Change-Id: Icefe078200f9a6a497b410e6c713d80fb9db1ba0 --- targets/demo/retarget.c | 276 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 276 insertions(+) create mode 100644 targets/demo/retarget.c (limited to 'targets/demo/retarget.c') diff --git a/targets/demo/retarget.c b/targets/demo/retarget.c new file mode 100644 index 0000000..3355e2e --- /dev/null +++ b/targets/demo/retarget.c @@ -0,0 +1,276 @@ +/* + * Copyright (c) 2019-2022 Arm Limited. + * + * 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 +#include +#include +#include + +#include "uart_stdout.h" + +// armclang retargeting +#if defined(__ARMCC_VERSION) && (__ARMCC_VERSION >= 6100100) +#include +#include + +/* Standard IO device handles. */ +#define STDIN 0x8001 +#define STDOUT 0x8002 +#define STDERR 0x8003 + +#define RETARGET(fun) _sys##fun +#define IO_OUTPUT(len) 0 + +#else +/* + * This type is used by the _ I/O functions to denote an open + * file. + */ +typedef int FILEHANDLE; + +/* + * Open a file. May return -1 if the file failed to open. + */ +extern FILEHANDLE _open(const char * /*name*/, int /*openmode*/); + +/* Standard IO device handles. */ +#define STDIN 0x00 +#define STDOUT 0x01 +#define STDERR 0x02 + +#define RETARGET(fun) fun +#define IO_OUTPUT(len) len + +#endif + +/* Standard IO device name defines. */ +const char __stdin_name[] __attribute__((aligned(4))) = "STDIN"; +const char __stdout_name[] __attribute__((aligned(4))) = "STDOUT"; +const char __stderr_name[] __attribute__((aligned(4))) = "STDERR"; + +void _ttywrch(int ch) { + (void)fputc(ch, stdout); +} + +FILEHANDLE RETARGET(_open)(const char *name, int openmode) { + (void)openmode; + + if (strcmp(name, __stdin_name) == 0) { + return (STDIN); + } + + if (strcmp(name, __stdout_name) == 0) { + return (STDOUT); + } + + if (strcmp(name, __stderr_name) == 0) { + return (STDERR); + } + + return -1; +} + +int RETARGET(_write)(FILEHANDLE fh, const unsigned char *buf, unsigned int len, int mode) { + (void)mode; + + switch (fh) { + case STDOUT: + case STDERR: { + int c; + unsigned int i; + + for (i = 0; i < len; i++) { + c = fputc(buf[i], stdout); + if (c == EOF) { + return EOF; + } + } + + return IO_OUTPUT(len); + } + default: + return EOF; + } +} + +int RETARGET(_read)(FILEHANDLE fh, unsigned char *buf, unsigned int len, int mode) { + (void)mode; + + switch (fh) { + case STDIN: { + int c; + unsigned int i; + + for (i = 0; i < len; i++) { + c = fgetc(stdin); + if (c == EOF) { + return EOF; + } + + buf[i] = (unsigned char)c; + } + + return IO_OUTPUT(len); + } + default: + return EOF; + } +} + +int RETARGET(_istty)(FILEHANDLE fh) { + switch (fh) { + case STDIN: + case STDOUT: + case STDERR: + return 1; + default: + return 0; + } +} + +int RETARGET(_close)(FILEHANDLE fh) { + if (RETARGET(_istty(fh))) { + return 0; + } + + return -1; +} + +int RETARGET(_seek)(FILEHANDLE fh, long pos) { + (void)fh; + (void)pos; + + return -1; +} + +int RETARGET(_ensure)(FILEHANDLE fh) { + (void)fh; + + return -1; +} + +long RETARGET(_flen)(FILEHANDLE fh) { + if (RETARGET(_istty)(fh)) { + return 0; + } + + return -1; +} + +int RETARGET(_tmpnam)(char *name, int sig, unsigned maxlen) { + (void)name; + (void)sig; + (void)maxlen; + + return 1; +} + +char *RETARGET(_command_string)(char *cmd, int len) { + (void)len; + + return cmd; +} + +void RETARGET(_exit)(int return_code) { + char exit_code_buffer[64] = {0}; + const char *p = exit_code_buffer; + + /* Print out the exit code on the uart so any reader know how we exit. */ + /* By appending 0x04, ASCII for end-of-transmission the FVP model exits, + * if the configuration parameter shutdown_on_eot on the uart is enabled. + * For some versions of FVP, the shutdown_on_eot is broken, but the same + * behaviour can be created by passing specifying a shutdown_tag= for the + * uart when starting the model so that is added last as well. + */ + + snprintf(exit_code_buffer, + sizeof(exit_code_buffer), + "Application exit code: %d.\n" // Let the readers know how we exit + "\04\n" // end-of-transmission + "EXITTHESIM\n", // shutdown_tag + return_code); + + while (*p != '\0') { + UartPutc(*p++); + } + + while (1) {} +} + +int system(const char *cmd) { + (void)cmd; + + return 0; +} + +time_t time(time_t *timer) { + time_t current; + + current = 0; // To Do !! No RTC implemented + + if (timer != NULL) { + *timer = current; + } + + return current; +} + +void _clock_init(void) { +#if 0 + // Example implementation based on SysTick + // For instance, use a counting var in a SysTick interrupt handler + // for clock() to use + SysTick->LOAD = (uint32_t) ((SystemCoreClock/100)-1UL); + NVIC_SetPriority (SysTick_IRQn, (1UL << __NVIC_PRIO_BITS) - 1UL); + SysTick->VAL = 0UL; + SysTick->CTRL = SysTick_CTRL_CLKSOURCE_Msk | SysTick_CTRL_TICKINT_Msk | SysTick_CTRL_ENABLE_Msk; +#endif +} + +clock_t clock(void) { + return (clock_t)-1; +} + +int remove(const char *arg) { + (void)arg; + return 0; +} + +int rename(const char *oldn, const char *newn) { + (void)oldn; + (void)newn; + return 0; +} + +int fputc(int ch, FILE *f) { + (void)(f); + return UartPutc(ch); +} + +int fgetc(FILE *f) { + (void)f; + return UartPutc(UartGetc()); +} + +#ifndef ferror +/* arm-none-eabi-gcc with newlib uses a define for ferror */ +int ferror(FILE *f) { + (void)f; + return EOF; +} +#endif -- cgit v1.2.1