diff options
| -rw-r--r-- | drivers/mmc/host/sdhci-st.c | 59 |
1 files changed, 59 insertions, 0 deletions
diff --git a/drivers/mmc/host/sdhci-st.c b/drivers/mmc/host/sdhci-st.c index 74213b0bc94f..1fbea9af7ae4 100644 --- a/drivers/mmc/host/sdhci-st.c +++ b/drivers/mmc/host/sdhci-st.c @@ -122,6 +122,65 @@ struct st_mmc_platform_data { ST_TOP_MMC_DLY_CTRL_ATUNE_NOT_CFG_DLY | \ ST_TOP_MMC_START_DLL_LOCK) +/* + * For clock speeds greater than 90MHz, we need to check that the + * DLL procedure has finished before switching to ultra-speed modes. + */ +#define CLK_TO_CHECK_DLL_LOCK 90000000 + +static inline void st_mmcss_set_static_delay(void __iomem *ioaddr) +{ + if (!ioaddr) + return; + + writel_relaxed(0x0, ioaddr + ST_TOP_MMC_DLY_CTRL); + writel_relaxed(ST_TOP_MMC_DLY_MAX, + ioaddr + ST_TOP_MMC_TX_CLK_DLY); +} + +static inline void st_mmcss_set_dll(void __iomem *ioaddr) +{ + if (!ioaddr) + return; + + writel_relaxed(ST_TOP_MMC_DYN_DLY_CONF, ioaddr + ST_TOP_MMC_DLY_CTRL); + writel_relaxed(ST_TOP_MMC_TX_DLL_STEP_DLY_VALID, + ioaddr + ST_TOP_MMC_TX_DLL_STEP_DLY); +} + +static int st_mmcss_lock_dll(void __iomem *ioaddr) +{ + unsigned long curr, value; + unsigned long finish = jiffies + HZ; + + /* Checks if the DLL procedure is finished */ + do { + curr = jiffies; + value = readl(ioaddr + ST_MMC_STATUS_R); + if (value & 0x1) + return 0; + + cpu_relax(); + } while (!time_after_eq(curr, finish)); + + return -EBUSY; +} + +static int sdhci_st_set_dll_for_clock(struct sdhci_host *host) +{ + int ret = 0; + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); + struct st_mmc_platform_data *pdata = pltfm_host->priv; + + if (host->clock > CLK_TO_CHECK_DLL_LOCK) { + st_mmcss_set_dll(pdata->top_ioaddr); + ret = st_mmcss_lock_dll(host->ioaddr); + } + + return ret; +} + + static u32 sdhci_st_readl(struct sdhci_host *host, int reg) { u32 ret; |