From: Iker Pedrosa Date: Mon, 11 May 2026 08:53:57 +0000 (+0200) Subject: mmc: sdhci-of-k1: enable essential clock infrastructure for SD operation X-Git-Url: http://git.ipfire.org/gitweb/index.cgi?a=commitdiff_plain;h=f87b273e4b6dfe57dcd63c24cbe3764d1f6954ae;p=thirdparty%2Fkernel%2Flinux.git mmc: sdhci-of-k1: enable essential clock infrastructure for SD operation Ensure SD card pins receive clock signals by enabling pad clock generation and overriding automatic clock gating. Required for all SD operation modes. The SDHC_GEN_PAD_CLK_ON setting in LEGACY_CTRL_REG is safe for both SD and eMMC operation as both protocols use the same physical MMC interface pins and require proper clock signal generation at the hardware level for signal integrity and timing. Additional SD-specific clock overrides (SDHC_OVRRD_CLK_OEN and SDHC_FORCE_CLK_ON) are conditionally applied only for SD-only controllers to handle removable card scenarios. Tested-by: Anand Moon Acked-by: Adrian Hunter Tested-by: Trevor Gamblin Reviewed-by: Troy Mitchell Tested-by: Vincent Legoll Signed-off-by: Iker Pedrosa Signed-off-by: Ulf Hansson --- diff --git a/drivers/mmc/host/sdhci-of-k1.c b/drivers/mmc/host/sdhci-of-k1.c index 455656f9842df..0dd06fc19b857 100644 --- a/drivers/mmc/host/sdhci-of-k1.c +++ b/drivers/mmc/host/sdhci-of-k1.c @@ -21,6 +21,13 @@ #include "sdhci.h" #include "sdhci-pltfm.h" +#define SPACEMIT_SDHC_OP_EXT_REG 0x108 +#define SDHC_OVRRD_CLK_OEN BIT(11) +#define SDHC_FORCE_CLK_ON BIT(12) + +#define SPACEMIT_SDHC_LEGACY_CTRL_REG 0x10C +#define SDHC_GEN_PAD_CLK_ON BIT(6) + #define SPACEMIT_SDHC_MMC_CTRL_REG 0x114 #define SDHC_MISC_INT_EN BIT(1) #define SDHC_MISC_INT BIT(2) @@ -101,6 +108,12 @@ static void spacemit_sdhci_reset(struct sdhci_host *host, u8 mask) if (!(host->mmc->caps2 & MMC_CAP2_NO_MMC)) spacemit_sdhci_setbits(host, SDHC_MMC_CARD_MODE, SPACEMIT_SDHC_MMC_CTRL_REG); + + spacemit_sdhci_setbits(host, SDHC_GEN_PAD_CLK_ON, SPACEMIT_SDHC_LEGACY_CTRL_REG); + + if (host->mmc->caps2 & MMC_CAP2_NO_MMC) + spacemit_sdhci_setbits(host, SDHC_OVRRD_CLK_OEN | SDHC_FORCE_CLK_ON, + SPACEMIT_SDHC_OP_EXT_REG); } static void spacemit_sdhci_set_uhs_signaling(struct sdhci_host *host, unsigned int timing)