Commit 764384d0 authored by Faiz Abbas's avatar Faiz Abbas Committed by Ulf Hansson
Browse files

mmc: sdhci_am654: Enable tuning for SDR50 

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: default avatarFaiz Abbas <faiz_abbas@ti.com>
Link: https://lore.kernel.org/r/20200923105206.7988-7-faiz_abbas@ti.com


Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
parent 13ebeae6

drivers/mmc/host/sdhci_am654.c

+6 −0
Original line number Diff line number Diff line
@@ -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;