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>

diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index 4e4e0fb..cbd7567 100644 (file)
--- a/drivers/mmc/mmc.c
+++ b/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;
                }
 

diff --git a/drivers/mmc/s5p_mmc.c b/drivers/mmc/s5p_mmc.c
index 280738f..f136813 100644 (file)
--- a/drivers/mmc/s5p_mmc.c
+++ b/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;

diff --git a/include/mmc.h b/include/mmc.h
index 1c8a360..53aff9b 100644 (file)
--- a/include/mmc.h
+++ b/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