According to the SW tuning App note[1], tuning is required for all UHS speed modes. Tuning for SDR50 is not enabled in Capabilities by default so enable it from the CTL_CFG registers. [1] https://www.ti.com/lit/pdf/spract9 Signed-off-by: Faiz Abbas <faiz_abbas@xxxxxx> --- drivers/mmc/host/sdhci_am654.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/mmc/host/sdhci_am654.c b/drivers/mmc/host/sdhci_am654.c index 5af7638ad606..2bce962bf7e4 100644 --- a/drivers/mmc/host/sdhci_am654.c +++ b/drivers/mmc/host/sdhci_am654.c @@ -19,9 +19,11 @@ /* CTL_CFG Registers */ #define CTL_CFG_2 0x14 +#define CTL_CFG_3 0x18 #define SLOTTYPE_MASK GENMASK(31, 30) #define SLOTTYPE_EMBEDDED BIT(30) +#define TUNINGFORSDR50_MASK BIT(13) /* PHY Registers */ #define PHY_CTRL1 0x100 @@ -646,6 +648,10 @@ static int sdhci_am654_init(struct sdhci_host *host) regmap_update_bits(sdhci_am654->base, CTL_CFG_2, SLOTTYPE_MASK, ctl_cfg_2); + /* Enable tuning for SDR50 */ + regmap_update_bits(sdhci_am654->base, CTL_CFG_3, TUNINGFORSDR50_MASK, + TUNINGFORSDR50_MASK); + ret = sdhci_setup_host(host); if (ret) return ret; -- 2.17.1
