Added an optional check in the CFI driver to evaluate if the sector is already blank before issuing an erase command. Improves erase time by over a factor of 10 if already blank.
Signed-off-by: Joe Hershberger joe.hershberger@ni.com --- drivers/mtd/cfi_flash.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+)
diff --git a/drivers/mtd/cfi_flash.c b/drivers/mtd/cfi_flash.c index f0f301a..97a4fd7 100644 --- a/drivers/mtd/cfi_flash.c +++ b/drivers/mtd/cfi_flash.c @@ -1078,6 +1078,32 @@ int flash_erase (flash_info_t * info, int s_first, int s_last)
for (sect = s_first; sect <= s_last; sect++) { if (info->protect[sect] == 0) { /* not protected */ +#ifdef CONFIG_SYS_FLASH_CHECK_BLANK_BEFORE_ERASE + int k; + int size; + int erased; + u32 *flash; + + /* + * Check if whole sector is erased + */ + size = flash_sector_size(info, sect); + erased = 1; + flash = (u32 *)info->start[sect]; + /* divide by 4 for longword access */ + size = size >> 2; + for (k = 0; k < size; k++) { + if (flash_read32(flash++) != 0xffffffff) { + erased = 0; + break; + } + } + if (erased) { + if (flash_verbose) + putc(','); + continue; + } +#endif switch (info->vendor) { case CFI_CMDSET_INTEL_PROG_REGIONS: case CFI_CMDSET_INTEL_STANDARD: