imx233: fix sd init sequence

Implement the switch function as specified by the specification,
that is wait for the response AND transfer 64 bytes of data. This
fixes some issue when the SD card take a long time to switch. In
particular waiting 100ms (max per spec) will not work if no data
is transfered in some cases.

Change-Id: Ia22350468018b842e57ce6f6c1a8d676eba97fb8

1 files changed, 12 insertions, 4 deletions

diff --git a/firmware/target/arm/imx233/sdmmc-imx233.c b/firmware/target/arm/imx233/sdmmc-imx233.c
index b74c21c08c..c389a1d2c8 100644
--- a/firmware/target/arm/imx233/sdmmc-imx233.c
+++ b/firmware/target/arm/imx233/sdmmc-imx233.c
@@ -353,8 +353,17 @@ static int init_sd_card(int drive)
             return -6;
 
         /* CMD6 */
-        if(!send_cmd(drive, SD_SWITCH_FUNC, 0x80fffff1, MCI_RESP, NULL))
-            return -7;
+        {
+            /* only transfer 64 bytes */
+            imx233_ssp_set_block_size(ssp, /*log2(64)*/6);
+            if(imx233_ssp_sd_mmc_transfer(ssp, SD_SWITCH_FUNC, 0x80fffff1,
+                    SSP_SHORT_RESP, aligned_buffer[drive], 1, true, true, NULL))
+            {
+                imx233_ssp_set_block_size(ssp, /*log2(512)*/9);
+                return -12;
+            }
+            imx233_ssp_set_block_size(ssp, /*log2(512)*/9);
+        }
 
         /*  go back to STBY state so we can read csd */
         /*  CMD7 w/rca=0:  Deselect card to put it in STBY state */
@@ -465,10 +474,9 @@ static int init_mmc_drive(int drive)
 
     /* read extended CSD */
     {
-        uint8_t ext_csd[512];
+        uint8_t *ext_csd = aligned_buffer[drive];
         if(imx233_ssp_sd_mmc_transfer(ssp, 8, 0, SSP_SHORT_RESP, aligned_buffer[drive], 1, true, true, &status))
             return -12;
-        memcpy(ext_csd, aligned_buffer[drive], 512);
         uint32_t *sec_count = (void *)&ext_csd[212];
         window_start[drive] = 0;
         window_end[drive] = *sec_count;