From db3585d181221dd025fcdece9d56b02da63cfe96 Mon Sep 17 00:00:00 2001 From: Heinrich Schuchardt Date: Thu, 6 Aug 2020 12:34:59 +0200 Subject: [PATCH] cmd: exception: unaligned data access on RISC-V The command 'exception' can be used to test the handling of exceptions. Currently the exception command only allows to create an illegal instruction exception on RISC-V. Provide a sub-command 'exception unaligned' to cause a misaligned load address exception. Adjust the online help for 'exception undefined'. Signed-off-by: Heinrich Schuchardt Reviewed-by: Rick Chen --- cmd/riscv/exception.c | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) diff --git a/cmd/riscv/exception.c b/cmd/riscv/exception.c index 3c8dbbec0e..9687cec812 100644 --- a/cmd/riscv/exception.c +++ b/cmd/riscv/exception.c @@ -8,6 +8,18 @@ #include #include +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[]) { @@ -16,6 +28,8 @@ static int do_undefined(struct cmd_tbl *cmdtp, int flag, int argc, } static struct cmd_tbl cmd_sub[] = { + U_BOOT_CMD_MKENT(unaligned, CONFIG_SYS_MAXARGS, 1, do_unaligned, + "", ""), U_BOOT_CMD_MKENT(undefined, CONFIG_SYS_MAXARGS, 1, do_undefined, "", ""), }; @@ -23,7 +37,8 @@ static struct cmd_tbl cmd_sub[] = { static char exception_help_text[] = "\n" " The following exceptions are available:\n" - " undefined - undefined instruction\n" + " undefined - illegal instruction\n" + " unaligned - load address misaligned\n" ; #include