mirror of
https://github.com/u-boot/u-boot.git
synced 2025-04-24 14:25:56 +00:00
d678a59d2d
When bringing in the series 'arm: dts: am62-beagleplay: Fix Beagleplay Ethernet"' I failed to notice that b4 noticed it was based on next and so took that as the base commit and merged that part of next to master. This reverts commitc8ffd1356d, reversing changes made to2ee6f3a5f7. Reported-by: Jonas Karlman <jonas@kwiboo.se> Signed-off-by: Tom Rini <trini@konsulko.com>
89 lines
2.5 KiB
C
89 lines
2.5 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>
|
|
#include <linux/bitops.h>
|
|
|
|
static int do_undefined(struct cmd_tbl *cmdtp, int flag, int argc,
|
|
char *const argv[])
|
|
{
|
|
/*
|
|
* Instructions starting with the upper 16 bits all 0 are permanently
|
|
* undefined. The lower 16 bits can be used for some kind of immediate.
|
|
* --- ARMv8 ARM (ARM DDI 0487G.a C6.2.339: "UDF")
|
|
*/
|
|
asm volatile (".word 0x00001234\n");
|
|
|
|
return CMD_RET_FAILURE;
|
|
}
|
|
|
|
/*
|
|
* The ID_AA64MMFR2_EL1 register name is only know to binutils for ARMv8.2
|
|
* and later architecture revisions. However the register is valid regardless
|
|
* of binutils architecture support or the core the code is running on, so
|
|
* just use the generic encoding.
|
|
*/
|
|
#define ID_AA64MMFR2_EL1 "S3_0_C0_C7_2"
|
|
|
|
static int do_unaligned(struct cmd_tbl *cmdtp, int flag, int argc,
|
|
char *const argv[])
|
|
{
|
|
uint64_t reg;
|
|
|
|
/*
|
|
* The unaligned LDAR access below is only guaranteed to generate an
|
|
* alignment fault on cores not implementing FEAT_LSE2. To avoid false
|
|
* negatives, check this condition before we exectute LDAR.
|
|
*/
|
|
asm ("mrs %0, "ID_AA64MMFR2_EL1"\n" : "=r" (reg));
|
|
if (reg & GENMASK(35, 32)) {
|
|
printf("unaligned access check only supported on pre-v8.4 cores\n");
|
|
return CMD_RET_FAILURE;
|
|
}
|
|
|
|
/*
|
|
* The load acquire instruction requires the data source to be
|
|
* naturally aligned, and will fault even if strict alignment fault
|
|
* checking is disabled (but only without FEAT_LSE2).
|
|
* --- ARMv8 ARM (ARM DDI 0487G.a B2.5.2: "Alignment of data accesses")
|
|
*/
|
|
asm volatile (
|
|
"mov x1, sp\n\t"
|
|
"orr x1, x1, #3\n\t"
|
|
"ldar x0, [x1]\n"
|
|
::: "x0", "x1" );
|
|
|
|
return CMD_RET_FAILURE;
|
|
}
|
|
|
|
static int do_breakpoint(struct cmd_tbl *cmdtp, int flag, int argc,
|
|
char *const argv[])
|
|
{
|
|
asm volatile ("brk #123\n");
|
|
|
|
return CMD_RET_FAILURE;
|
|
}
|
|
|
|
static struct cmd_tbl cmd_sub[] = {
|
|
U_BOOT_CMD_MKENT(breakpoint, CONFIG_SYS_MAXARGS, 1, do_breakpoint,
|
|
"", ""),
|
|
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"
|
|
" breakpoint - breakpoint instruction exception\n"
|
|
" unaligned - unaligned LDAR data abort\n"
|
|
" undefined - undefined instruction exception\n"
|
|
;
|
|
|
|
#include <exception.h>
|