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path: root/drivers/mmc/host/sdhci-st.c
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Diffstat (limited to 'drivers/mmc/host/sdhci-st.c')
-rw-r--r--drivers/mmc/host/sdhci-st.c59
1 files changed, 59 insertions, 0 deletions
diff --git a/drivers/mmc/host/sdhci-st.c b/drivers/mmc/host/sdhci-st.c
index 74213b0..1fbea9a 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;
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