u-boot/common/cmd_sf.c
Kumar Gala 8e8a4bc22f cmd_sf: Fix compiler warning
cmd_sf.c: In function 'do_spi_flash':
cmd_sf.c:164:9: warning: 'skipped' may be used uninitialized in this function

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Acked-by: Simon Glass <sjg@chromium.org>
2011-10-05 22:22:17 +02:00

312 lines
7.3 KiB
C

/*
* Command for accessing SPI flash.
*
* Copyright (C) 2008 Atmel Corporation
* Licensed under the GPL-2 or later.
*/
#include <common.h>
#include <malloc.h>
#include <spi_flash.h>
#include <asm/io.h>
#ifndef CONFIG_SF_DEFAULT_SPEED
# define CONFIG_SF_DEFAULT_SPEED 1000000
#endif
#ifndef CONFIG_SF_DEFAULT_MODE
# define CONFIG_SF_DEFAULT_MODE SPI_MODE_3
#endif
static struct spi_flash *flash;
/*
* This function computes the length argument for the erase command.
* The length on which the command is to operate can be given in two forms:
* 1. <cmd> offset len - operate on <'offset', 'len')
* 2. <cmd> offset +len - operate on <'offset', 'round_up(len)')
* If the second form is used and the length doesn't fall on the
* sector boundary, than it will be adjusted to the next sector boundary.
* If it isn't in the flash, the function will fail (return -1).
* Input:
* arg: length specification (i.e. both command arguments)
* Output:
* len: computed length for operation
* Return:
* 1: success
* -1: failure (bad format, bad address).
*/
static int sf_parse_len_arg(char *arg, ulong *len)
{
char *ep;
char round_up_len; /* indicates if the "+length" form used */
ulong len_arg;
round_up_len = 0;
if (*arg == '+') {
round_up_len = 1;
++arg;
}
len_arg = simple_strtoul(arg, &ep, 16);
if (ep == arg || *ep != '\0')
return -1;
if (round_up_len && flash->sector_size > 0)
*len = ROUND(len_arg, flash->sector_size);
else
*len = len_arg;
return 1;
}
static int do_spi_flash_probe(int argc, char * const argv[])
{
unsigned int bus = 0;
unsigned int cs;
unsigned int speed = CONFIG_SF_DEFAULT_SPEED;
unsigned int mode = CONFIG_SF_DEFAULT_MODE;
char *endp;
struct spi_flash *new;
if (argc < 2)
return -1;
cs = simple_strtoul(argv[1], &endp, 0);
if (*argv[1] == 0 || (*endp != 0 && *endp != ':'))
return -1;
if (*endp == ':') {
if (endp[1] == 0)
return -1;
bus = cs;
cs = simple_strtoul(endp + 1, &endp, 0);
if (*endp != 0)
return -1;
}
if (argc >= 3) {
speed = simple_strtoul(argv[2], &endp, 0);
if (*argv[2] == 0 || *endp != 0)
return -1;
}
if (argc >= 4) {
mode = simple_strtoul(argv[3], &endp, 16);
if (*argv[3] == 0 || *endp != 0)
return -1;
}
new = spi_flash_probe(bus, cs, speed, mode);
if (!new) {
printf("Failed to initialize SPI flash at %u:%u\n", bus, cs);
return 1;
}
if (flash)
spi_flash_free(flash);
flash = new;
return 0;
}
/**
* Write a block of data to SPI flash, first checking if it is different from
* what is already there.
*
* If the data being written is the same, then *skipped is incremented by len.
*
* @param flash flash context pointer
* @param offset flash offset to write
* @param len number of bytes to write
* @param buf buffer to write from
* @param cmp_buf read buffer to use to compare data
* @param skipped Count of skipped data (incremented by this function)
* @return NULL if OK, else a string containing the stage which failed
*/
static const char *spi_flash_update_block(struct spi_flash *flash, u32 offset,
size_t len, const char *buf, char *cmp_buf, size_t *skipped)
{
debug("offset=%#x, sector_size=%#x, len=%#x\n",
offset, flash->sector_size, len);
if (spi_flash_read(flash, offset, len, cmp_buf))
return "read";
if (memcmp(cmp_buf, buf, len) == 0) {
debug("Skip region %x size %x: no change\n",
offset, len);
*skipped += len;
return NULL;
}
if (spi_flash_erase(flash, offset, len))
return "erase";
if (spi_flash_write(flash, offset, len, buf))
return "write";
return NULL;
}
/**
* Update an area of SPI flash by erasing and writing any blocks which need
* to change. Existing blocks with the correct data are left unchanged.
*
* @param flash flash context pointer
* @param offset flash offset to write
* @param len number of bytes to write
* @param buf buffer to write from
* @return 0 if ok, 1 on error
*/
static int spi_flash_update(struct spi_flash *flash, u32 offset,
size_t len, const char *buf)
{
const char *err_oper = NULL;
char *cmp_buf;
const char *end = buf + len;
size_t todo; /* number of bytes to do in this pass */
size_t skipped = 0; /* statistics */
cmp_buf = malloc(flash->sector_size);
if (cmp_buf) {
for (; buf < end && !err_oper; buf += todo, offset += todo) {
todo = min(end - buf, flash->sector_size);
err_oper = spi_flash_update_block(flash, offset, todo,
buf, cmp_buf, &skipped);
}
} else {
err_oper = "malloc";
}
free(cmp_buf);
if (err_oper) {
printf("SPI flash failed in %s step\n", err_oper);
return 1;
}
printf("%zu bytes written, %zu bytes skipped\n", len - skipped,
skipped);
return 0;
}
static int do_spi_flash_read_write(int argc, char * const argv[])
{
unsigned long addr;
unsigned long offset;
unsigned long len;
void *buf;
char *endp;
int ret;
if (argc < 4)
return -1;
addr = simple_strtoul(argv[1], &endp, 16);
if (*argv[1] == 0 || *endp != 0)
return -1;
offset = simple_strtoul(argv[2], &endp, 16);
if (*argv[2] == 0 || *endp != 0)
return -1;
len = simple_strtoul(argv[3], &endp, 16);
if (*argv[3] == 0 || *endp != 0)
return -1;
buf = map_physmem(addr, len, MAP_WRBACK);
if (!buf) {
puts("Failed to map physical memory\n");
return 1;
}
if (strcmp(argv[0], "update") == 0)
ret = spi_flash_update(flash, offset, len, buf);
else if (strcmp(argv[0], "read") == 0)
ret = spi_flash_read(flash, offset, len, buf);
else
ret = spi_flash_write(flash, offset, len, buf);
unmap_physmem(buf, len);
if (ret) {
printf("SPI flash %s failed\n", argv[0]);
return 1;
}
return 0;
}
static int do_spi_flash_erase(int argc, char * const argv[])
{
unsigned long offset;
unsigned long len;
char *endp;
int ret;
if (argc < 3)
return -1;
offset = simple_strtoul(argv[1], &endp, 16);
if (*argv[1] == 0 || *endp != 0)
return -1;
ret = sf_parse_len_arg(argv[2], &len);
if (ret != 1)
return -1;
ret = spi_flash_erase(flash, offset, len);
if (ret) {
printf("SPI flash %s failed\n", argv[0]);
return 1;
}
return 0;
}
static int do_spi_flash(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
const char *cmd;
int ret;
/* need at least two arguments */
if (argc < 2)
goto usage;
cmd = argv[1];
--argc;
++argv;
if (strcmp(cmd, "probe") == 0) {
ret = do_spi_flash_probe(argc, argv);
goto done;
}
/* The remaining commands require a selected device */
if (!flash) {
puts("No SPI flash selected. Please run `sf probe'\n");
return 1;
}
if (strcmp(cmd, "read") == 0 || strcmp(cmd, "write") == 0 ||
strcmp(cmd, "update") == 0)
ret = do_spi_flash_read_write(argc, argv);
else if (strcmp(cmd, "erase") == 0)
ret = do_spi_flash_erase(argc, argv);
else
ret = -1;
done:
if (ret != -1)
return ret;
usage:
return cmd_usage(cmdtp);
}
U_BOOT_CMD(
sf, 5, 1, do_spi_flash,
"SPI flash sub-system",
"probe [bus:]cs [hz] [mode] - init flash device on given SPI bus\n"
" and chip select\n"
"sf read addr offset len - read `len' bytes starting at\n"
" `offset' to memory at `addr'\n"
"sf write addr offset len - write `len' bytes from memory\n"
" at `addr' to flash at `offset'\n"
"sf erase offset [+]len - erase `len' bytes from `offset'\n"
" `+len' round up `len' to block size\n"
"sf update addr offset len - erase and write `len' bytes from memory\n"
" at `addr' to flash at `offset'"
);