diff options
Diffstat (limited to 'drivers/mmc')
| -rw-r--r-- | drivers/mmc/host/sdhci-of-at91.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/drivers/mmc/host/sdhci-of-at91.c b/drivers/mmc/host/sdhci-of-at91.c index c1923c094ff6..25f779e09d8e 100644 --- a/drivers/mmc/host/sdhci-of-at91.c +++ b/drivers/mmc/host/sdhci-of-at91.c @@ -18,6 +18,7 @@ #include <linux/delay.h> #include <linux/err.h> #include <linux/io.h> +#include <linux/kernel.h> #include <linux/mmc/host.h> #include <linux/mmc/slot-gpio.h> #include <linux/module.h> @@ -32,6 +33,8 @@ #define SDMMC_CACR_CAPWREN BIT(0) #define SDMMC_CACR_KEY (0x46 << 8) +#define SDHCI_AT91_PRESET_COMMON_CONF 0x400 /* drv type B, programmable clock mode */ + struct sdhci_at91_priv { struct clk *hclock; struct clk *gck; @@ -163,6 +166,7 @@ static int sdhci_at91_probe(struct platform_device *pdev) unsigned int clk_base, clk_mul; unsigned int gck_rate, real_gck_rate; int ret; + unsigned int preset_div; match = of_match_device(sdhci_at91_dt_match, &pdev->dev); if (!match) @@ -230,6 +234,28 @@ static int sdhci_at91_probe(struct platform_device *pdev) clk_mul, real_gck_rate); } + /* + * We have to set preset values because it depends on the clk_mul + * value. Moreover, SDR104 is supported in a degraded mode since the + * maximum sd clock value is 120 MHz instead of 208 MHz. For that + * reason, we need to use presets to support SDR104. + */ + preset_div = DIV_ROUND_UP(real_gck_rate, 24000000) - 1; + writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div, + host->ioaddr + SDHCI_PRESET_FOR_SDR12); + preset_div = DIV_ROUND_UP(real_gck_rate, 50000000) - 1; + writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div, + host->ioaddr + SDHCI_PRESET_FOR_SDR25); + preset_div = DIV_ROUND_UP(real_gck_rate, 100000000) - 1; + writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div, + host->ioaddr + SDHCI_PRESET_FOR_SDR50); + preset_div = DIV_ROUND_UP(real_gck_rate, 120000000) - 1; + writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div, + host->ioaddr + SDHCI_PRESET_FOR_SDR104); + preset_div = DIV_ROUND_UP(real_gck_rate, 50000000) - 1; + writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div, + host->ioaddr + SDHCI_PRESET_FOR_DDR50); + clk_prepare_enable(priv->mainck); clk_prepare_enable(priv->gck); |