From: Hu Ziji <huziji@xxxxxxxxxxx>
Support HS400 Enhanced Strobe feature in Xenon.
Enable Enhanced Strobe together with Data Strobe.
Disable Enhanced Strobe when eMMC is not in HS400 mode.
Signed-off-by: Hu Ziji <huziji@xxxxxxxxxxx>
Signed-off-by: Zhoujie Wu <zjwu@xxxxxxxxxxx>
---
drivers/mmc/host/sdhci-xenon-phy.c | 34 ++++++++++++++++++++++++++++------
drivers/mmc/host/sdhci-xenon.h | 1 +
2 files changed, 29 insertions(+), 6 deletions(-)
diff --git a/drivers/mmc/host/sdhci-xenon-phy.c b/drivers/mmc/host/sdhci-xenon-phy.c
index f7e26b0..ec87943 100644
--- a/drivers/mmc/host/sdhci-xenon-phy.c
+++ b/drivers/mmc/host/sdhci-xenon-phy.c
@@ -409,17 +409,30 @@ static int xenon_emmc_phy_config_tuning(struct sdhci_host *host)
return 0;
}
-static void xenon_emmc_phy_disable_data_strobe(struct sdhci_host *host)
+static void xenon_emmc_phy_disable_strobe(struct sdhci_host *host)
{
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct xenon_priv *priv = sdhci_pltfm_priv(pltfm_host);
u32 reg;
- /* Disable SDHC Data Strobe */
+ /* Disable both SDHC Data Strobe and Enhanced Strobe */
reg = sdhci_readl(host, XENON_SLOT_EMMC_CTRL);
- reg &= ~XENON_ENABLE_DATA_STROBE;
+ reg &= ~(XENON_ENABLE_DATA_STROBE | XENON_ENABLE_RESP_STROBE);
sdhci_writel(host, reg, XENON_SLOT_EMMC_CTRL);
+
+ /* Clear Strobe line Pull down or Pull up */
+ if (priv->phy_type == EMMC_5_0_PHY) {
+ reg = sdhci_readl(host, XENON_EMMC_5_0_PHY_PAD_CONTROL);
+ reg &= ~(XENON_EMMC5_FC_QSP_PD | XENON_EMMC5_FC_QSP_PU);
+ sdhci_writel(host, reg, XENON_EMMC_5_0_PHY_PAD_CONTROL);
+ } else {
+ reg = sdhci_readl(host, XENON_EMMC_PHY_PAD_CONTROL1);
+ reg &= ~(XENON_EMMC5_1_FC_QSP_PD | XENON_EMMC5_1_FC_QSP_PU);
+ sdhci_writel(host, reg, XENON_EMMC_PHY_PAD_CONTROL1);
+ }
}
-/* Set HS400 Data Strobe */
+/* Set HS400 Data Strobe and Enhanced Strobe */
static void xenon_emmc_phy_strobe_delay_adj(struct sdhci_host *host)
{
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
@@ -439,6 +452,15 @@ static void xenon_emmc_phy_strobe_delay_adj(struct sdhci_host *host)
/* Enable SDHC Data Strobe */
reg = sdhci_readl(host, XENON_SLOT_EMMC_CTRL);
reg |= XENON_ENABLE_DATA_STROBE;
+ /*
+ * Enable SDHC Enhanced Strobe if supported
+ * Xenon Enhanced Strobe should be enabled only when
+ * 1. card is in HS400 mode and
+ * 2. SDCLK is higher than 52MHz
+ * 3. DLL is enabled
+ */
+ if (host->mmc->ios.enhanced_strobe)
+ reg |= XENON_ENABLE_RESP_STROBE;
sdhci_writel(host, reg, XENON_SLOT_EMMC_CTRL);
/* Set Data Strobe Pull down */
@@ -615,7 +637,7 @@ static void xenon_emmc_phy_set(struct sdhci_host *host,
sdhci_writel(host, phy_regs->logic_timing_val,
phy_regs->logic_timing_adj);
else
- xenon_emmc_phy_disable_data_strobe(host);
+ xenon_emmc_phy_disable_strobe(host);
phy_init:
xenon_emmc_phy_init(host);
@@ -705,7 +727,7 @@ void xenon_soc_pad_ctrl(struct sdhci_host *host,
/*
* Setting PHY when card is working in High Speed Mode.
- * HS400 set data strobe line.
+ * HS400 set Data Strobe and Enhanced Strobe if it is supported.
* HS200/SDR104 set tuning config to prepare for tuning.
*/
static int xenon_hs_delay_adj(struct sdhci_host *host)
diff --git a/drivers/mmc/host/sdhci-xenon.h b/drivers/mmc/host/sdhci-xenon.h
index 73debb4..01937f1 100644
--- a/drivers/mmc/host/sdhci-xenon.h
+++ b/drivers/mmc/host/sdhci-xenon.h
@@ -33,6 +33,7 @@
#define XENON_TUNING_STEP_DIVIDER BIT(6)
#define XENON_SLOT_EMMC_CTRL 0x0130
+#define XENON_ENABLE_RESP_STROBE BIT(25)
#define XENON_ENABLE_DATA_STROBE BIT(24)
#define XENON_SLOT_RETUNING_REQ_CTRL 0x0144
--
1.9.1
--
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