fix(rpi3): initialize SD card host controller

Add initial configuration parameters for Rasperry Pi 3's sdhost
controller, and then configure and use those parameters.

This change allows warm reboots of UEFI on Raspberry Pi 3B+ where
existing code often fails with "unknown error". See discussion at:

https://github.com/pftf/RPi3/issues/24

The basic idea is that some initial configuration parameters
(clock rate, bus width) aren't configured into the hardware before
commands start being sent. I suspect that the particular setting
that matters is the "slow card" bit, but the initial clock setting
also seemed wrong to me.

Change-Id: I526def340def143f23f3422f1fc14c12c937ca7f
Signed-off-by: Rob Newberry <robthedude@mac.com>

diff --git a/drivers/rpi3/sdhost/rpi3_sdhost.c b/drivers/rpi3/sdhost/rpi3_sdhost.c
index c4b6fcafeca87093fe0a90eae335203f1ad3a9b1..90c850947baaf17cd8e9ff719b1226dfe887b0e6 100644 (file)
--- a/drivers/rpi3/sdhost/rpi3_sdhost.c
+++ b/drivers/rpi3/sdhost/rpi3_sdhost.c
@@ -245,13 +245,12 @@ static void rpi3_sdhost_reset(void)
 
 static void rpi3_sdhost_initialize(void)
 {
-       uintptr_t reg_base = rpi3_sdhost_params.reg_base;
-
        assert((rpi3_sdhost_params.reg_base & MMC_BLOCK_MASK) == 0);
 
        rpi3_sdhost_reset();
 
-       mmio_write_32(reg_base + HC_CLOCKDIVISOR, HC_CLOCKDIVISOR_PREFERVAL);
+       rpi3_sdhost_set_ios(rpi3_sdhost_params.clk_rate_initial,
+               rpi3_sdhost_params.bus_width);
        udelay(300);
 }
 

diff --git a/include/drivers/rpi3/sdhost/rpi3_sdhost.h b/include/drivers/rpi3/sdhost/rpi3_sdhost.h
index 1653240c899709736a66fc4d8160fe1e14204a3d..f4f6ec8b2ce08506842b8573c6be6caa9e8f79cd 100644 (file)
--- a/include/drivers/rpi3/sdhost/rpi3_sdhost.h
+++ b/include/drivers/rpi3/sdhost/rpi3_sdhost.h
@@ -15,6 +15,7 @@
 struct rpi3_sdhost_params {
        uintptr_t       reg_base;
        uint32_t        clk_rate;
+       uint32_t        clk_rate_initial;
        uint32_t        bus_width;
        uint32_t        flags;
        uint32_t        current_cmd;
@@ -57,6 +58,8 @@ void rpi3_sdhost_stop(void);
 #define HC_CMD_READ                    0x0040
 #define HC_CMD_COMMAND_MASK            0x003f
 
+#define RPI3_SDHOST_MAX_CLOCK          250000000       // technically, we should obtain this number from the mailbox
+
 #define HC_CLOCKDIVISOR_MAXVAL         0x07ff
 #define HC_CLOCKDIVISOR_PREFERVAL      0x027b
 #define HC_CLOCKDIVISOR_SLOWVAL                0x0148

diff --git a/plat/rpi/rpi3/rpi3_bl2_setup.c b/plat/rpi/rpi3/rpi3_bl2_setup.c
index db718179450a3438e8bdf1592963141725dac3d1..80e4d8d8dbccf56ea5219939a910a968a82b5843 100644 (file)
--- a/plat/rpi/rpi3/rpi3_bl2_setup.c
+++ b/plat/rpi/rpi3/rpi3_bl2_setup.c
@@ -35,7 +35,9 @@ static void rpi3_sdhost_setup(void)
        params.reg_base = RPI3_SDHOST_BASE;
        params.bus_width = MMC_BUS_WIDTH_1;
        params.clk_rate = 50000000;
+       params.clk_rate_initial = (RPI3_SDHOST_MAX_CLOCK / HC_CLOCKDIVISOR_MAXVAL);
        mmc_info.mmc_dev_type = MMC_IS_SD_HC;
+       mmc_info.ocr_voltage = OCR_3_2_3_3 | OCR_3_3_3_4;
        rpi3_sdhost_init(&params, &mmc_info);
 }