Hi Przemyslaw,
On 17 February 2015 at 06:09, Przemyslaw Marczak p.marczak@samsung.com wrote:
Before this commit, the mmc devices were always registered in the same order. So dwmmc channel 0 was registered as mmc 0, channel 1 as mmc 1, etc. In case of possibility to boot from more then one device, the CONFIG_SYS_MMC_ENV_DEV should always point to right mmc device.
This can be achieved by init boot device as first, so it will be always registered as mmc 0. Thanks to this, the 'saveenv' command will work fine for all mmc boot devices.
Exynos based boards usually uses mmc host channels configuration:
- 0, or 0+1 for 8 bit - as a default boot device (usually eMMC)
- 2 for 4bit - as an optional boot device (usually SD card slot)
And usually the boot order is defined by OM pin configuration, which can be changed in a few ways, eg.
- Odroid U3 - eMMC card insertion -> first boot from eMMC
- Odroid X2/XU3 - boot priority jumper
By this commit, Exynos dwmmc driver will check the OM pin configuration, and then try to init the boot device and register it as mmc 0.
I think a better way to do this would be to make CONFIG_SYS_MMC_ENV_DEV support an option where the device can be selected at run-time.
However that would probably be better done when the drive rmodel conversion is complete.
So this seems a reasonable patch given where we are.
Reviewed-by: Simon Glass sjg@chromium.org
Signed-off-by: Przemyslaw Marczak p.marczak@samsung.com Cc: Minkyu Kang mk7.kang@samsung.com Cc: Jaehoon Chung jh80.chung@samsung.com Cc: Pantelis Antoniou panto@intracom.gr Cc: Simon Glass sjg@chromium.org Cc: Akshay Saraswat akshay.s@samsung.com
drivers/mmc/exynos_dw_mmc.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/drivers/mmc/exynos_dw_mmc.c b/drivers/mmc/exynos_dw_mmc.c index dfa209b..91f0163 100644 --- a/drivers/mmc/exynos_dw_mmc.c +++ b/drivers/mmc/exynos_dw_mmc.c @@ -13,6 +13,7 @@ #include <asm/arch/dwmmc.h> #include <asm/arch/clk.h> #include <asm/arch/pinmux.h> +#include <asm/arch/power.h> #include <asm/gpio.h> #include <asm-generic/errno.h>
@@ -166,7 +167,6 @@ static int exynos_dwmci_get_config(const void *blob, int node, if (host->dev_index == host->dev_id) host->dev_index = host->dev_id - PERIPH_ID_SDMMC0;
/* Get the bus width from the device node */ host->buswidth = fdtdec_get_int(blob, node, "samsung,bus-width", 0); if (host->buswidth <= 0) {@@ -229,12 +229,21 @@ int exynos_dwmmc_init(const void *blob) { int compat_id; int node_list[DWMMC_MAX_CH_NUM];
int boot_dev_node; int err = 0, count; compat_id = COMPAT_SAMSUNG_EXYNOS_DWMMC; count = fdtdec_find_aliases_for_id(blob, "mmc", compat_id, node_list, DWMMC_MAX_CH_NUM);/* For DWMMC always set boot device as mmc 0 */if (count >= 3 && get_boot_mode() == BOOT_MODE_SD) {boot_dev_node = node_list[2];node_list[2] = node_list[0];node_list[0] = boot_dev_node;}err = exynos_dwmci_process_node(blob, node_list, count); return err;-- 1.9.1
Regards, Simon