diff options
| -rw-r--r-- | common/cmd_sf.c | 86 |
1 files changed, 83 insertions, 3 deletions
diff --git a/common/cmd_sf.c b/common/cmd_sf.c index 27d6e39..c8c547a 100644 --- a/common/cmd_sf.c +++ b/common/cmd_sf.c @@ -6,6 +6,7 @@ */ #include <common.h> +#include <malloc.h> #include <spi_flash.h> #include <asm/io.h> @@ -109,6 +110,80 @@ static int do_spi_flash_probe(int argc, char * const argv[]) 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; /* statistics */ + + cmp_buf = malloc(flash->sector_size); + if (cmp_buf) { + for (skipped = 0; 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; @@ -137,7 +212,9 @@ static int do_spi_flash_read_write(int argc, char * const argv[]) return 1; } - if (strcmp(argv[0], "read") == 0) + 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); @@ -203,7 +280,8 @@ static int do_spi_flash(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[ return 1; } - if (strcmp(cmd, "read") == 0 || strcmp(cmd, "write") == 0) + 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); @@ -228,5 +306,7 @@ U_BOOT_CMD( "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" + " `+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'" ); |