new file mode 100644
@@ -0,0 +1,29 @@
+diff -Naur a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
+--- a/drivers/mmc/mmc.c 2016-05-16 16:40:32.000000000 +0200
++++ b/drivers/mmc/mmc.c 2016-07-11 13:23:13.235880737 +0200
+@@ -1351,25 +1351,6 @@
+ mmc->card_caps &= mmc->cfg->host_caps;
+
+ if (IS_SD(mmc)) {
+- if (mmc->card_caps & MMC_MODE_4BIT) {
+- cmd.cmdidx = MMC_CMD_APP_CMD;
+- cmd.resp_type = MMC_RSP_R1;
+- cmd.cmdarg = mmc->rca << 16;
+-
+- err = mmc_send_cmd(mmc, &cmd, NULL);
+- if (err)
+- return err;
+-
+- cmd.cmdidx = SD_CMD_APP_SET_BUS_WIDTH;
+- cmd.resp_type = MMC_RSP_R1;
+- cmd.cmdarg = 2;
+- err = mmc_send_cmd(mmc, &cmd, NULL);
+- if (err)
+- return err;
+-
+- mmc_set_bus_width(mmc, 4);
+- }
+-
+ if (mmc->card_caps & MMC_MODE_HS)
+ mmc->tran_speed = 50000000;
+ else
Early AM335x-evm boards can only use 1 bit communication to the SD card, on newer board revisions this might be fixed. Forcing 1 bit communication slows down the communication but will work regardless if the SD card is attached via 1 or 4 bits. If the board has a working 4 bit SD card interface, this patch can be removed, this will speed up the access. Signed-off-by: Lothar Felten <lothar.felten@gmail.com> --- .../uboot/0001-mmc-force-1bit-bus-width.patch | 29 ++++++++++++++++++++++ 1 file changed, 29 insertions(+) create mode 100644 board/ti/am335x-evm/patches/uboot/0001-mmc-force-1bit-bus-width.patch