cfi_flash: Add missing check for erased dest to flash_write_cfibuffer()

The check for an sufficiently erased destination was missing in the
buffered write function of the cfi flash driver (when
CFG_FLASH_USE_BUFFER_WRITE is defined). This patch adds this check to that
writing to such a region will fail with the currect error message.

Signed-off-by: Stefan Roese <sr@denx.de>

diff --git a/drivers/mtd/cfi_flash.c b/drivers/mtd/cfi_flash.c
index f370e4fbd3f7d95f27eee193efc4689f0ed64322..d1124d3439e1d083cd7cc7de44df5a6c1603d3bb 100644 (file)
--- a/drivers/mtd/cfi_flash.c
+++ b/drivers/mtd/cfi_flash.c
@@ -769,7 +769,7 @@ static int flash_write_cfiword (flash_info_t * info, ulong dest,
        }
        if (!flag) {
                unmap_physmem(dstaddr, info->portwidth);
-               return 2;
+               return ERR_NOT_ERASED;
        }
 
        /* Disable interrupts which might cause a timeout here */
@@ -826,7 +826,57 @@ static int flash_write_cfibuffer (flash_info_t * info, ulong dest, uchar * cp,
        int retcode;
        void *src = cp;
        void *dst = map_physmem(dest, len, MAP_NOCACHE);
+       void *dst2 = dst;
+       int flag = 0;
 
+       switch (info->portwidth) {
+       case FLASH_CFI_8BIT:
+               cnt = len;
+               break;
+       case FLASH_CFI_16BIT:
+               cnt = len >> 1;
+               break;
+       case FLASH_CFI_32BIT:
+               cnt = len >> 2;
+               break;
+       case FLASH_CFI_64BIT:
+               cnt = len >> 3;
+               break;
+       default:
+               retcode = ERR_INVAL;
+               goto out_unmap;
+       }
+
+       while ((cnt-- > 0) && (flag == 0)) {
+               switch (info->portwidth) {
+               case FLASH_CFI_8BIT:
+                       flag = ((flash_read8(dst2) & flash_read8(src)) ==
+                               flash_read8(src));
+                       src += 1, dst2 += 1;
+                       break;
+               case FLASH_CFI_16BIT:
+                       flag = ((flash_read16(dst2) & flash_read16(src)) ==
+                               flash_read16(src));
+                       src += 2, dst2 += 2;
+                       break;
+               case FLASH_CFI_32BIT:
+                       flag = ((flash_read32(dst2) & flash_read32(src)) ==
+                               flash_read32(src));
+                       src += 4, dst2 += 4;
+                       break;
+               case FLASH_CFI_64BIT:
+                       flag = ((flash_read64(dst2) & flash_read64(src)) ==
+                               flash_read64(src));
+                       src += 8, dst2 += 8;
+                       break;
+               }
+       }
+       if (!flag) {
+               retcode = ERR_NOT_ERASED;
+               goto out_unmap;
+       }
+
+       src = cp;
        sector = find_sector (info, dest);
 
        switch (info->vendor) {