u-boot/arch/blackfin/lib/cmd_cache_dump.c
Wolfgang Denk 54841ab50c Make sure that argv[] argument pointers are not modified.
The hush shell dynamically allocates (and re-allocates) memory for the
argument strings in the "char *argv[]" argument vector passed to
commands.  Any code that modifies these pointers will cause serious
corruption of the malloc data structures and crash U-Boot, so make
sure the compiler can check that no such modifications are being done
by changing the code into "char * const argv[]".

This modification is the result of debugging a strange crash caused
after adding a new command, which used the following argument
processing code which has been working perfectly fine in all Unix
systems since version 6 - but not so in U-Boot:

int main (int argc, char **argv)
{
	while (--argc > 0 && **++argv == '-') {
/* ====> */	while (*++*argv) {
			switch (**argv) {
			case 'd':
				debug++;
				break;
			...
			default:
				usage ();
			}
		}
	}
	...
}

The line marked "====>" will corrupt the malloc data structures and
usually cause U-Boot to crash when the next command gets executed by
the shell.  With the modification, the compiler will prevent this with
an
	error: increment of read-only location '*argv'

N.B.: The code above can be trivially rewritten like this:

	while (--argc > 0 && **++argv == '-') {
		char *arg = *argv;
		while (*++arg) {
			switch (*arg) {
			...

Signed-off-by: Wolfgang Denk <wd@denx.de>
Acked-by: Mike Frysinger <vapier@gentoo.org>
2010-07-04 23:55:42 +02:00

146 lines
3.6 KiB
C

/*
* U-boot - cmd_cache_dump.c
*
* Copyright (c) 2007-2008 Analog Devices Inc.
*
* Licensed under the GPL-2 or later.
*/
#include <config.h>
#include <common.h>
#include <command.h>
#include <asm/blackfin.h>
#include <asm/mach-common/bits/mpu.h>
static int check_limit(const char *type, size_t start_limit, size_t end_limit, size_t start, size_t end)
{
if (start >= start_limit && start <= end_limit && \
end <= end_limit && end >= start_limit && \
start <= end)
return 0;
printf("%s limit violation: %zu <= (user:%zu) <= (user:%zu) <= %zu\n",
type, start_limit, start, end, end_limit);
return 1;
}
int do_icache_dump(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
int cache_status = icache_status();
if (cache_status)
icache_disable();
uint32_t cmd_base, tag, cache_upper, cache_lower;
size_t way, way_start = 0, way_end = 3;
size_t sbnk, sbnk_start = 0, sbnk_end = 3;
size_t set, set_start = 0, set_end = 31;
size_t dw;
if (argc > 1) {
way_start = way_end = simple_strtoul(argv[1], NULL, 10);
if (argc > 2) {
sbnk_start = sbnk_end = simple_strtoul(argv[2], NULL, 10);
if (argc > 3)
set_start = set_end = simple_strtoul(argv[3], NULL, 10);
}
}
if (check_limit("way", 0, 3, way_start, way_end) || \
check_limit("subbank", 0, 3, sbnk_start, sbnk_end) || \
check_limit("set", 0, 31, set_start, set_end))
return 1;
puts("Way:Subbank:Set: [valid-tag lower upper] {invalid-tag lower upper}...\n");
for (way = way_start; way <= way_end; ++way) {
for (sbnk = sbnk_start; sbnk <= sbnk_end; ++sbnk) {
for (set = set_start; set <= set_end; ++set) {
printf("%zu:%zu:%2zu: ", way, sbnk, set);
for (dw = 0; dw < 4; ++dw) {
if (ctrlc())
return 1;
cmd_base = \
(way << 26) | \
(sbnk << 16) | \
(set << 5) | \
(dw << 3);
/* first read the tag */
bfin_write_ITEST_COMMAND(cmd_base | 0x0);
SSYNC();
tag = bfin_read_ITEST_DATA0();
printf("%c%08x ", (tag & 0x1 ? ' ' : '{'), tag);
/* grab the data at this loc */
bfin_write_ITEST_COMMAND(cmd_base | 0x4);
SSYNC();
cache_lower = bfin_read_ITEST_DATA0();
cache_upper = bfin_read_ITEST_DATA1();
printf("%08x %08x%c ", cache_lower, cache_upper, (tag & 0x1 ? ' ' : '}'));
}
puts("\n");
}
}
}
if (cache_status)
icache_enable();
return 0;
}
U_BOOT_CMD(icache_dump, 4, 0, do_icache_dump,
"icache_dump - dump current instruction cache\n",
"[way] [subbank] [set]");
int do_dcache_dump(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
u32 way, bank, subbank, set;
u32 status, addr;
u32 dmem_ctl = bfin_read_DMEM_CONTROL();
for (bank = 0; bank < 2; ++bank) {
if (!(dmem_ctl & (1 << (DMC1_P - bank))))
continue;
for (way = 0; way < 2; ++way)
for (subbank = 0; subbank < 4; ++subbank) {
printf("%i:%i:%i:\t", bank, way, subbank);
for (set = 0; set < 64; ++set) {
if (ctrlc())
return 1;
/* retrieve a cache tag */
bfin_write_DTEST_COMMAND(
way << 26 |
bank << 23 |
subbank << 16 |
set << 5
);
CSYNC();
status = bfin_read_DTEST_DATA0();
/* construct the address using the tag */
addr = (status & 0xFFFFC800) | (subbank << 12) | (set << 5);
/* show it */
if (set && !(set % 4))
puts("\n\t");
printf("%c%08x%c%08x%c ", (status & 0x1 ? '[' : '{'), status, (status & 0x2 ? 'd' : ' '), addr, (status & 0x1 ? ']' : '}'));
}
puts("\n");
}
}
return 0;
}
U_BOOT_CMD(dcache_dump, 4, 0, do_dcache_dump,
"dcache_dump - dump current data cache\n",
"[bank] [way] [subbank] [set]");