mmc: subtract boot sectors from disk size for eMMC 4.3+ devices

the csd sector count reported by eMMC 4.3+ cards includes the boot
partition size; subtract this from the size reported to the disk
since the boot partition is inaccessible

Change-Id: I601b83aa0159b7aa446409ea8c945b256dd0b5b1
Signed-off-by: Gary King <gking@nvidia.com>

diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 6909a54c39beac1a8ca277f317f43c4a4ea9d583..f5b2aaf2371f1f3d854212e6d9ac62bf6786ddcf 100644 (file)
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -253,8 +253,13 @@ static int mmc_read_ext_csd(struct mmc_card *card)
                        ext_csd[EXT_CSD_SEC_CNT + 3] << 24;
 
                /* Cards with density > 2GiB are sector addressed */
-               if (card->ext_csd.sectors > (2u * 1024 * 1024 * 1024) / 512)
+               if (card->ext_csd.sectors > (2u * 1024 * 1024 * 1024) / 512) {
+                       unsigned boot_sectors;
+                       boot_sectors = ext_csd[EXT_CSD_BOOT_SIZE_MULTI];
+                       boot_sectors *= SZ_256K / 512;
+                       card->ext_csd.sectors -= boot_sectors;
                        mmc_card_set_blockaddr(card);
+               }
        }
 
        switch (ext_csd[EXT_CSD_CARD_TYPE] & EXT_CSD_CARD_TYPE_MASK) {

diff --git a/include/linux/mmc/mmc.h b/include/linux/mmc/mmc.h
index dd11ae51fb68e8b847300a5fe78ac049c9ef8605..5b35987e691b792e91583a8f716c5d13877825b6 100644 (file)
--- a/include/linux/mmc/mmc.h
+++ b/include/linux/mmc/mmc.h
@@ -262,6 +262,7 @@ struct _mmc_csd {
 #define EXT_CSD_S_A_TIMEOUT            217     /* RO */
 #define EXT_CSD_ERASE_TIMEOUT_MULT     223     /* RO */
 #define EXT_CSD_HC_ERASE_GRP_SIZE      224     /* RO */
+#define EXT_CSD_BOOT_SIZE_MULTI                226
 #define EXT_CSD_SEC_TRIM_MULT          229     /* RO */
 #define EXT_CSD_SEC_ERASE_MULT         230     /* RO */
 #define EXT_CSD_SEC_FEATURE_SUPPORT    231     /* RO */