mmc: Access mode validation for eMMC cards > 2 GiB

This patch provides handling of the two way handshake when SEND_OP_COND
(CMD1) is send to mmc card. It is necessary to inform eMMC card if the
host can work with high capacity cards (Jedec JESD84-A441, point 7.4.3).

The extra flag MMC_MODE_HC (high capacity) is added to indicate if the
host is capable of handling the high capacity eMMC cards.

Since this change is added to the generic mmc framework, then it requires
other boards to indicate if their mmc controllers can handle high capacity
cards. As it is now - the old behaviour of the framework is preserved.

Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
Signed-off-by: Andy Fleming <afleming@freescale.com>

drivers/mmc/mmc.c

@@ -531,6 +531,10 @@ int mmc_send_op_cond(struct mmc *mmc)
 				(mmc->voltages &
 				(cmd.response[0] & OCR_VOLTAGE_MASK)) |
 				(cmd.response[0] & OCR_ACCESS_MODE));
+
+		if (mmc->host_caps & MMC_MODE_HC)
+			cmd.cmdarg |= OCR_HCS;
+
 		cmd.flags = 0;
 
 		err = mmc_send_cmd(mmc, &cmd, NULL);
@@ -1010,7 +1014,7 @@ int mmc_startup(struct mmc *mmc)
 			capacity = ext_csd[212] << 0 | ext_csd[213] << 8 |
 				   ext_csd[214] << 16 | ext_csd[215] << 24;
 			capacity *= 512;
-			if (capacity > 2 * 1024 * 1024 * 1024)
+			if ((capacity >> 20) > 2 * 1024)
 				mmc->capacity = capacity;
 		}
 

drivers/mmc/s5p_mmc.c

@@ -462,7 +462,7 @@ static int s5p_mmc_initialize(int dev_index, int bus_width)
 		mmc->host_caps = MMC_MODE_8BIT;
 	else
 		mmc->host_caps = MMC_MODE_4BIT;
-	mmc->host_caps |= MMC_MODE_HS_52MHz | MMC_MODE_HS;
+	mmc->host_caps |= MMC_MODE_HS_52MHz | MMC_MODE_HS | MMC_MODE_HC;
 
 	mmc->f_min = 400000;
 	mmc->f_max = 52000000;

include/mmc.h

@@ -45,6 +45,7 @@
 #define MMC_MODE_4BIT		0x100
 #define MMC_MODE_8BIT		0x200
 #define MMC_MODE_SPI		0x400
+#define MMC_MODE_HC		0x800
 
 #define SD_DATA_4BIT	0x00040000