[PATCH v2 4/8] mmc: zynq_sdhci: Read clock phase delays from dt

[Michal Simek]

Define input and output clock phase delays with pre-defined values.

Define arasan_sdhci_clk_data type structure and add it to priv
structure and store these clock phase delays in it.

Read input and output clock phase delays from dt. If these values are
not passed through dt, use pre-defined values.

Signed-off-by: Ashok Reddy Soma <ashok.reddy.soma at xilinx.com>
Signed-off-by: Michal Simek <michal.simek at xilinx.com>
---

(no changes since v1)

 drivers/mmc/zynq_sdhci.c | 85 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 85 insertions(+)

diff --git a/drivers/mmc/zynq_sdhci.c b/drivers/mmc/zynq_sdhci.c
index 998a38450680..e69f375cce07 100644
--- a/drivers/mmc/zynq_sdhci.c
+++ b/drivers/mmc/zynq_sdhci.c
@@ -20,6 +20,12 @@
 #include <zynqmp_tap_delay.h>
 
 #define SDHCI_TUNING_LOOP_COUNT		40
+#define MMC_BANK2			0x2
+
+struct arasan_sdhci_clk_data {
+	int clk_phase_in[MMC_TIMING_MMC_HS400 + 1];
+	int clk_phase_out[MMC_TIMING_MMC_HS400 + 1];
+};
 
 struct arasan_sdhci_plat {
 	struct mmc_config cfg;
@@ -28,12 +34,17 @@ struct arasan_sdhci_plat {
 
 struct arasan_sdhci_priv {
 	struct sdhci_host *host;
+	struct arasan_sdhci_clk_data clk_data;
 	u8 deviceid;
 	u8 bank;
 	u8 no_1p8;
 };
 
 #if defined(CONFIG_ARCH_ZYNQMP)
+/* Default settings for ZynqMP Clock Phases */
+const u32 zynqmp_iclk_phases[] = {0, 63, 63, 0, 63,  0,   0, 183, 54,  0, 0};
+const u32 zynqmp_oclk_phases[] = {0, 72, 60, 0, 60, 72, 135, 48, 72, 135, 0};
+
 static const u8 mode2timing[] = {
 	[MMC_LEGACY] = MMC_TIMING_LEGACY,
 	[MMC_HS] = MMC_TIMING_MMC_HS,
@@ -168,6 +179,79 @@ static void arasan_sdhci_set_tapdelay(struct sdhci_host *host)
 					   priv->bank);
 }
 
+static void arasan_dt_read_clk_phase(struct udevice *dev, unsigned char timing,
+				     const char *prop)
+{
+	struct arasan_sdhci_priv *priv = dev_get_priv(dev);
+	struct arasan_sdhci_clk_data *clk_data = &priv->clk_data;
+	u32 clk_phase[2] = {0};
+
+	/*
+	 * Read Tap Delay values from DT, if the DT does not contain the
+	 * Tap Values then use the pre-defined values
+	 */
+	if (dev_read_u32_array(dev, prop, &clk_phase[0], 2)) {
+		dev_dbg(dev, "Using predefined clock phase for %s = %d %d\n",
+			prop, clk_data->clk_phase_in[timing],
+			clk_data->clk_phase_out[timing]);
+		return;
+	}
+
+	/* The values read are Input and Output Clock Delays in order */
+	clk_data->clk_phase_in[timing] = clk_phase[0];
+	clk_data->clk_phase_out[timing] = clk_phase[1];
+}
+
+/**
+ * arasan_dt_parse_clk_phases - Read Tap Delay values from DT
+ *
+ * Called at initialization to parse the values of Tap Delays.
+ *
+ * @dev:                Pointer to our struct udevice.
+ */
+static void arasan_dt_parse_clk_phases(struct udevice *dev)
+{
+	struct arasan_sdhci_priv *priv = dev_get_priv(dev);
+	struct arasan_sdhci_clk_data *clk_data = &priv->clk_data;
+	int i;
+
+	if (IS_ENABLED(CONFIG_ARCH_ZYNQMP) &&
+	    device_is_compatible(dev, "xlnx,zynqmp-8.9a")) {
+		for (i = 0; i <= MMC_TIMING_MMC_HS400; i++) {
+			clk_data->clk_phase_in[i] = zynqmp_iclk_phases[i];
+			clk_data->clk_phase_out[i] = zynqmp_oclk_phases[i];
+		}
+
+		if (priv->bank == MMC_BANK2) {
+			clk_data->clk_phase_out[MMC_TIMING_UHS_SDR104] = 90;
+			clk_data->clk_phase_out[MMC_TIMING_MMC_HS200] = 90;
+		}
+	}
+
+	arasan_dt_read_clk_phase(dev, MMC_TIMING_LEGACY,
+				 "clk-phase-legacy");
+	arasan_dt_read_clk_phase(dev, MMC_TIMING_MMC_HS,
+				 "clk-phase-mmc-hs");
+	arasan_dt_read_clk_phase(dev, MMC_TIMING_SD_HS,
+				 "clk-phase-sd-hs");
+	arasan_dt_read_clk_phase(dev, MMC_TIMING_UHS_SDR12,
+				 "clk-phase-uhs-sdr12");
+	arasan_dt_read_clk_phase(dev, MMC_TIMING_UHS_SDR25,
+				 "clk-phase-uhs-sdr25");
+	arasan_dt_read_clk_phase(dev, MMC_TIMING_UHS_SDR50,
+				 "clk-phase-uhs-sdr50");
+	arasan_dt_read_clk_phase(dev, MMC_TIMING_UHS_SDR104,
+				 "clk-phase-uhs-sdr104");
+	arasan_dt_read_clk_phase(dev, MMC_TIMING_UHS_DDR50,
+				 "clk-phase-uhs-ddr50");
+	arasan_dt_read_clk_phase(dev, MMC_TIMING_MMC_DDR52,
+				 "clk-phase-mmc-ddr52");
+	arasan_dt_read_clk_phase(dev, MMC_TIMING_MMC_HS200,
+				 "clk-phase-mmc-hs200");
+	arasan_dt_read_clk_phase(dev, MMC_TIMING_MMC_HS400,
+				 "clk-phase-mmc-hs400");
+}
+
 static void arasan_sdhci_set_control_reg(struct sdhci_host *host)
 {
 	struct mmc *mmc = (struct mmc *)host->mmc;
@@ -271,6 +355,7 @@ static int arasan_sdhci_ofdata_to_platdata(struct udevice *dev)
 
 #if defined(CONFIG_ARCH_ZYNQMP)
 	priv->host->ops = &arasan_ops;
+	arasan_dt_parse_clk_phases(dev);
 #endif
 
 	priv->host->ioaddr = (void *)dev_read_addr(dev);
-- 
2.28.0