[U-Boot] [PATCH ] MMC: fix user capacity for partitioned eMMC card

[Markus Niebel]

From: Markus Niebel <Markus.Niebel at tq-group.com>

if the card claims to be high capacity and the card
is partitioned the capacity shall still be read from
ext_csd SEC_COUNT even if the resulting capacity is
smaller than 2 GiB

Signed-off-by: Markus Niebel <Markus.Niebel at tq-group.com>
---
 drivers/mmc/mmc.c | 15 +++++++++++++++
 include/mmc.h     |  3 +++
 2 files changed, 18 insertions(+)

diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index 44a4feb..24b0989 100644
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -1022,6 +1022,21 @@ static int mmc_startup(struct mmc *mmc)
 			mmc->erase_grp_size =
 				ext_csd[EXT_CSD_HC_ERASE_GRP_SIZE] *
 					MMC_MAX_BLOCK_LEN * 1024;
+			/*
+			 * if high capacity and partition setting completed
+			 * SEC_COUNT is valid even if it is smaller than 2 GiB
+			 * JEDEC Standard JESD84-B45, 6.2.4
+			 */
+			if (mmc->high_capacity &&
+			    (ext_csd[EXT_CSD_PARTITION_SETTING] &
+			     EXT_CSD_PARTITION_SETTING_COMPLETED)) {
+				capacity = (ext_csd[EXT_CSD_SEC_CNT]) |
+					(ext_csd[EXT_CSD_SEC_CNT + 1] << 8) |
+					(ext_csd[EXT_CSD_SEC_CNT + 2] << 16) |
+					(ext_csd[EXT_CSD_SEC_CNT + 3] << 24);
+				capacity *= MMC_MAX_BLOCK_LEN;
+				mmc->capacity_user = capacity;
+			}
 		} else {
 			/* Calculate the group size from the csd value. */
 			int erase_gsz, erase_gmul;
diff --git a/include/mmc.h b/include/mmc.h
index d74a190..cb91565 100644
--- a/include/mmc.h
+++ b/include/mmc.h
@@ -147,6 +147,7 @@
  * EXT_CSD fields
  */
 #define EXT_CSD_GP_SIZE_MULT		143	/* R/W */
+#define EXT_CSD_PARTITION_SETTING	155	/* R/W */
 #define EXT_CSD_PARTITIONS_ATTRIBUTE	156	/* R/W */
 #define EXT_CSD_PARTITIONING_SUPPORT	160	/* RO */
 #define EXT_CSD_RST_N_FUNCTION		162	/* R/W */
@@ -197,6 +198,8 @@
 #define EXT_CSD_BOOT_BUS_WIDTH_RESET(x)	(x << 2)
 #define EXT_CSD_BOOT_BUS_WIDTH_WIDTH(x)	(x)
 
+#define EXT_CSD_PARTITION_SETTING_COMPLETED	(1 << 0)
+
 #define R1_ILLEGAL_COMMAND		(1 << 22)
 #define R1_APP_CMD			(1 << 5)
 
-- 
2.1.1