[PATCH 1/2] arm: mvebu: clearfog: Fix MMC detection

[Pali Rohár]

On Saturday 25 February 2023 11:42:19 Martin Rowe wrote:
> A388 Clearfog MMC is either SD Card or eMMC with different behaviour for
> both. Setting MMC_BROKEN_CD allows both to correctly detect MMC.
> 
> Signed-off-by: Martin Rowe <martin.p.rowe at gmail.com>

It looks like a hack but I think we do not have a better option for now.

If I understand the issue correctly then card-detect pin is unconnected
for eMMC variant and used for checking if SD card is present for SD
variant. Unconnected pin seems to have some internal pull-up/down which
reports not-present state for eMMC variant. eMMC does not have any
presence signal, so card-detect pin must be ignored for eMMC.

This looks like a chicken and egg problem and the only option to support
both variants is to ignore card-detect pin and always try to initialize
device connected to mmc controller (which may be eMMC or SD).

I do not know if there is a better option for ignoring card-detect pin
in u-boot, so:

Acked-by: Pali Rohár <pali at kernel.org>

> ---
>  configs/clearfog_defconfig      | 3 +--
>  configs/clearfog_sata_defconfig | 8 ++++----
>  2 files changed, 5 insertions(+), 6 deletions(-)
> 
> diff --git a/configs/clearfog_defconfig b/configs/clearfog_defconfig
> index 8cd35f9f1a..24e7c16ac7 100644
> --- a/configs/clearfog_defconfig
> +++ b/configs/clearfog_defconfig
> @@ -46,7 +46,6 @@ CONFIG_CMD_USB=y
>  CONFIG_CMD_TFTPPUT=y
>  CONFIG_CMD_CACHE=y
>  CONFIG_CMD_TIME=y
> -CONFIG_CMD_MVEBU_BUBT=y
>  CONFIG_ENV_OVERWRITE=y
>  CONFIG_ENV_MIN_ENTRIES=128
>  CONFIG_ARP_TIMEOUT=200
> @@ -59,7 +58,7 @@ CONFIG_DM_I2C=y
>  CONFIG_SYS_I2C_MVTWSI=y
>  CONFIG_I2C_EEPROM=y
>  CONFIG_SPL_I2C_EEPROM=y
> -CONFIG_SUPPORT_EMMC_BOOT=y
> +CONFIG_MMC_BROKEN_CD=y
>  CONFIG_MMC_SDHCI=y
>  CONFIG_MMC_SDHCI_SDMA=y
>  CONFIG_MMC_SDHCI_MV=y
> diff --git a/configs/clearfog_sata_defconfig b/configs/clearfog_sata_defconfig
> index e9b36150ea..84f900bf50 100644
> --- a/configs/clearfog_sata_defconfig
> +++ b/configs/clearfog_sata_defconfig
> @@ -6,11 +6,14 @@ CONFIG_TEXT_BASE=0x00800000
>  CONFIG_SPL_LIBCOMMON_SUPPORT=y
>  CONFIG_SPL_LIBGENERIC_SUPPORT=y
>  CONFIG_NR_DRAM_BANKS=2
> +CONFIG_HAS_CUSTOM_SYS_INIT_SP_ADDR=y
> +CONFIG_CUSTOM_SYS_INIT_SP_ADDR=0xff0000
>  CONFIG_TARGET_CLEARFOG=y
>  CONFIG_MVEBU_SPL_BOOT_DEVICE_SATA=y
>  CONFIG_DEFAULT_DEVICE_TREE="armada-388-clearfog"
>  CONFIG_SPL_TEXT_BASE=0x40000030
>  CONFIG_SPL_SERIAL=y
> +CONFIG_SPL_STACK=0x4002c000
>  CONFIG_SPL=y
>  CONFIG_DEBUG_UART_BASE=0xf1012000
>  CONFIG_DEBUG_UART_CLOCK=250000000
> @@ -18,8 +21,6 @@ CONFIG_SYS_LOAD_ADDR=0x800000
>  CONFIG_DEBUG_UART=y
>  CONFIG_AHCI=y
>  CONFIG_DISTRO_DEFAULTS=y
> -CONFIG_HAS_CUSTOM_SYS_INIT_SP_ADDR=y
> -CONFIG_CUSTOM_SYS_INIT_SP_ADDR=0xff0000
>  CONFIG_BOOTDELAY=3
>  CONFIG_USE_PREBOOT=y
>  CONFIG_SYS_CONSOLE_INFO_QUIET=y
> @@ -31,7 +32,6 @@ CONFIG_SPL_BSS_START_ADDR=0x40023000
>  CONFIG_SPL_BSS_MAX_SIZE=0x4000
>  CONFIG_SPL_SYS_MALLOC_SIMPLE=y
>  # CONFIG_SPL_SHARES_INIT_SP_ADDR is not set
> -CONFIG_SPL_STACK=0x4002c000
>  CONFIG_SPL_I2C=y
>  CONFIG_SYS_MAXARGS=32
>  CONFIG_CMD_TLV_EEPROM=y
> @@ -46,7 +46,6 @@ CONFIG_CMD_USB=y
>  CONFIG_CMD_TFTPPUT=y
>  CONFIG_CMD_CACHE=y
>  CONFIG_CMD_TIME=y
> -CONFIG_CMD_MVEBU_BUBT=y
>  CONFIG_ENV_OVERWRITE=y
>  CONFIG_ENV_MIN_ENTRIES=128
>  CONFIG_ARP_TIMEOUT=200
> @@ -59,6 +58,7 @@ CONFIG_DM_I2C=y
>  CONFIG_SYS_I2C_MVTWSI=y
>  CONFIG_I2C_EEPROM=y
>  CONFIG_SPL_I2C_EEPROM=y
> +CONFIG_MMC_BROKEN_CD=y
>  CONFIG_SUPPORT_EMMC_BOOT=y
>  CONFIG_MMC_SDHCI=y
>  CONFIG_MMC_SDHCI_SDMA=y
> -- 
> 2.39.2
>