u-boot/cmd/riscv/exception.c
Heinrich Schuchardt 91e4b7516d cmd/exception: support ebreak exception on RISC-V
The ebreak instruction should generate a breakpoint exception.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Rick Chen <rick@andestech.com>
2021-05-05 16:13:12 +08:00

55 lines
1.3 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* The 'exception' command can be used for testing exception handling.
*
* Copyright (c) 2018, Heinrich Schuchardt <xypron.glpk@gmx.de>
*/
#include <common.h>
#include <command.h>
static int do_ebreak(struct cmd_tbl *cmdtp, int flag, int argc,
char *const argv[])
{
asm volatile ("ebreak\n");
return CMD_RET_FAILURE;
}
static int do_unaligned(struct cmd_tbl *cmdtp, int flag, int argc,
char *const argv[])
{
asm volatile (
"auipc a1, 0\n"
"ori a1, a1, 3\n"
"lw a2, (0)(a1)\n"
);
printf("The system supports unaligned access.\n");
return CMD_RET_SUCCESS;
}
static int do_undefined(struct cmd_tbl *cmdtp, int flag, int argc,
char *const argv[])
{
asm volatile (".word 0xffffffff\n");
return CMD_RET_FAILURE;
}
static struct cmd_tbl cmd_sub[] = {
U_BOOT_CMD_MKENT(ebreak, CONFIG_SYS_MAXARGS, 1, do_ebreak,
"", ""),
U_BOOT_CMD_MKENT(unaligned, CONFIG_SYS_MAXARGS, 1, do_unaligned,
"", ""),
U_BOOT_CMD_MKENT(undefined, CONFIG_SYS_MAXARGS, 1, do_undefined,
"", ""),
};
static char exception_help_text[] =
"<ex>\n"
" The following exceptions are available:\n"
" ebreak - breakpoint\n"
" undefined - illegal instruction\n"
" unaligned - load address misaligned\n"
;
#include <exception.h>