[U-Boot] [PATCH 6/9] mmc: support the DDR mode for eMMC

[Jaehoon Chung]

Support the DDR mode.

Signed-off-by: Jaehoon Chung <jh80.chung at samsung.com>
---
 drivers/mmc/mmc.c |   15 ++++++++++++---
 include/mmc.h     |    7 +++++++
 2 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index bac07c2..2874780 100644
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -163,6 +163,9 @@ int mmc_set_blocklen(struct mmc *mmc, int len)
 {
 	struct mmc_cmd cmd;
 
+	if (mmc->card_caps & MMC_MODE_DDR_52MHz)
+		return 0;
+
 	cmd.cmdidx = MMC_CMD_SET_BLOCKLEN;
 	cmd.resp_type = MMC_RSP_R1;
 	cmd.cmdarg = len;
@@ -518,9 +521,11 @@ static int mmc_change_freq(struct mmc *mmc)
 		return 0;
 
 	/* High Speed is set, there are two types: 52MHz and 26MHz */
-	if (cardtype & EXT_CSD_CARD_TYPE_52)
+	if (cardtype & EXT_CSD_CARD_TYPE_52) {
+		if (cardtype & EXT_CSD_CARD_TYPE_DDR_52)
+			mmc->card_caps |= MMC_MODE_DDR_52MHz;
 		mmc->card_caps |= MMC_MODE_HS_52MHz | MMC_MODE_HS;
-	else
+	} else
 		mmc->card_caps |= MMC_MODE_HS;
 
 	return 0;
@@ -1057,6 +1062,8 @@ static int mmc_startup(struct mmc *mmc)
 
 		/* An array of possible bus widths in order of preference */
 		static unsigned ext_csd_bits[] = {
+			EXT_CSD_DDR_BUS_WIDTH_8,
+			EXT_CSD_DDR_BUS_WIDTH_4,
 			EXT_CSD_BUS_WIDTH_8,
 			EXT_CSD_BUS_WIDTH_4,
 			EXT_CSD_BUS_WIDTH_1,
@@ -1064,13 +1071,15 @@ static int mmc_startup(struct mmc *mmc)
 
 		/* An array to map CSD bus widths to host cap bits */
 		static unsigned ext_to_hostcaps[] = {
+			[EXT_CSD_DDR_BUS_WIDTH_4] = MMC_MODE_DDR_52MHz,
+			[EXT_CSD_DDR_BUS_WIDTH_8] = MMC_MODE_DDR_52MHz,
 			[EXT_CSD_BUS_WIDTH_4] = MMC_MODE_4BIT,
 			[EXT_CSD_BUS_WIDTH_8] = MMC_MODE_8BIT,
 		};
 
 		/* An array to map chosen bus width to an integer */
 		static unsigned widths[] = {
-			8, 4, 1,
+			8, 4, 8, 4, 1,
 		};
 
 		for (idx=0; idx < ARRAY_SIZE(ext_csd_bits); idx++) {
diff --git a/include/mmc.h b/include/mmc.h
index 6725ac8..5120d17 100644
--- a/include/mmc.h
+++ b/include/mmc.h
@@ -37,6 +37,7 @@
 #define MMC_MODE_8BIT		(1 << 3)
 #define MMC_MODE_SPI		(1 << 4)
 #define MMC_MODE_HC		(1 << 5)
+#define MMC_MODE_DDR_52MHz	(1 << 6)
 
 #define SD_DATA_4BIT	0x00040000
 
@@ -167,10 +168,16 @@
 
 #define EXT_CSD_CARD_TYPE_26	(1 << 0)	/* Card can run at 26MHz */
 #define EXT_CSD_CARD_TYPE_52	(1 << 1)	/* Card can run at 52MHz */
+#define EXT_CSD_CARD_TYPE_DDR_1_8V	(1 << 2)
+#define EXT_CSD_CARD_TYPE_DDR_1_2V	(1 << 3)
+#define EXT_CSD_CARD_TYPE_DDR_52	(EXT_CSD_CARD_TYPE_DDR_1_8V \
+					| EXT_CSD_CARD_TYPE_DDR_1_2V)
 
 #define EXT_CSD_BUS_WIDTH_1	0	/* Card is in 1 bit mode */
 #define EXT_CSD_BUS_WIDTH_4	1	/* Card is in 4 bit mode */
 #define EXT_CSD_BUS_WIDTH_8	2	/* Card is in 8 bit mode */
+#define EXT_CSD_DDR_BUS_WIDTH_4	5	/* Card is in 4 bit DDR mode */
+#define EXT_CSD_DDR_BUS_WIDTH_8	6	/* Card is in 8 bit DDR mode */
 
 #define EXT_CSD_BOOT_ACK_ENABLE			(1 << 6)
 #define EXT_CSD_BOOT_PARTITION_ENABLE		(1 << 3)
-- 
1.7.9.5