rpi3: sdhost: SDHost driver improvement
This commit improves the SDHost driver for RPi3 as following:
* Unblock MMC_CMD(17). Using MMC_CMD(17) is more efficient on
block reading.
* In some low probability that SEND_OP_COND might results CRC7
error. We can consider that the command runs correctly. We don't
need to retry this command so removing the code for retry.
* Using MMC_BUS_WIDTH_1 as MMC default value to improve the stability.
* Increase the clock to 50Mhz in data mode to speed up the io.
* Change the pull resistors configuration to gain more stability.
Signed-off-by: Ying-Chun Liu (PaulLiu) <paulliu@debian.org>
diff --git a/plat/rpi3/rpi3_bl2_setup.c b/plat/rpi3/rpi3_bl2_setup.c
index 3d1f8f9..b5e5835 100644
--- a/plat/rpi3/rpi3_bl2_setup.c
+++ b/plat/rpi3/rpi3_bl2_setup.c
@@ -44,8 +44,8 @@
memset(¶ms, 0, sizeof(struct rpi3_sdhost_params));
params.reg_base = RPI3_SDHOST_BASE;
- params.bus_width = MMC_BUS_WIDTH_4;
- params.clk_rate = 392464;
+ params.bus_width = MMC_BUS_WIDTH_1;
+ params.clk_rate = 50000000;
mmc_info.mmc_dev_type = MMC_IS_SD_HC;
rpi3_sdhost_init(¶ms, &mmc_info);
}