[PATCH 04/12] mci: arasan: read clk phases from DT

[Steffen Trumtrar <s.trumtrar@pengutronix.de>]

Depending on the used SDHCI mode the clock phases are different.
Import the helper function to get these values from the DT from linux v6.7.

Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
---
 drivers/mci/arasan-sdhci.c | 121 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 121 insertions(+)

diff --git a/drivers/mci/arasan-sdhci.c b/drivers/mci/arasan-sdhci.c
index cc1bad8b62..76022708cd 100644
--- a/drivers/mci/arasan-sdhci.c
+++ b/drivers/mci/arasan-sdhci.c
@@ -30,10 +30,33 @@
 #define SDHCI_ARASAN_BUS_WIDTH			4
 #define TIMEOUT_VAL				0xE
 
+#define ZYNQMP_CLK_PHASES			10
+#define ZYNQMP_CLK_PHASE_UHS_SDR104		6
+#define ZYNQMP_CLK_PHASE_HS200			9
+/* Default settings for ZynqMP Clock Phases */
+#define ZYNQMP_ICLK_PHASE {0, 63, 63, 0, 63,  0,   0, 183, 54,  0, 0}
+#define ZYNQMP_OCLK_PHASE {0, 72, 60, 0, 60, 72, 135, 48, 72, 135, 0}
+
+/**
+ * struct sdhci_arasan_clk_data - Arasan Controller Clock Data.
+ *
+ * @clk_phase_in:	Array of Input Clock Phase Delays for all speed modes
+ * @clk_phase_out:	Array of Output Clock Phase Delays for all speed modes
+ * @set_clk_delays:	Function pointer for setting Clock Delays
+ * @clk_of_data:	Platform specific runtime clock data storage pointer
+ */
+struct sdhci_arasan_clk_data {
+	int		clk_phase_in[ZYNQMP_CLK_PHASES + 1];
+	int		clk_phase_out[ZYNQMP_CLK_PHASES + 1];
+	void		(*set_clk_delays)(struct sdhci *host);
+	void		*clk_of_data;
+};
+
 struct arasan_sdhci_host {
 	struct mci_host		mci;
 	struct sdhci		sdhci;
 	unsigned int		quirks; /* Arasan deviations from spec */
+	struct sdhci_arasan_clk_data clk_data;
 /* Controller does not have CD wired and will not function normally without */
 #define SDHCI_ARASAN_QUIRK_FORCE_CDTEST		BIT(0)
 #define SDHCI_ARASAN_QUIRK_NO_1_8_V		BIT(1)
@@ -119,6 +142,7 @@ static int arasan_sdhci_init(struct mci_host *mci, struct device *dev)
 static void arasan_sdhci_set_clock(struct mci_host *mci, unsigned int clock)
 {
 	struct arasan_sdhci_host *host = to_arasan_sdhci_host(mci);
+	struct sdhci_arasan_clk_data *clk_data = &host->clk_data;
 
 	if (host->quirks & SDHCI_ARASAN_QUIRK_CLOCK_25_BROKEN) {
 		/*
@@ -219,6 +243,101 @@ static int arasan_sdhci_send_cmd(struct mci_host *mci, struct mci_cmd *cmd,
 	return ret;
 }
 
+static void sdhci_arasan_set_clk_delays(struct sdhci *host)
+{
+	struct arasan_sdhci_host *arasan_sdhci = sdhci_to_arasan(host);
+	struct mci_host *mci = &arasan_sdhci->mci;
+	struct sdhci_arasan_clk_data *clk_data = &arasan_sdhci->clk_data;
+
+}
+
+static void arasan_dt_read_clk_phase(struct device *dev,
+				     struct sdhci_arasan_clk_data *clk_data,
+				     unsigned int timing, const char *prop)
+{
+	struct device_node *np = dev->of_node;
+
+	u32 clk_phase[2] = {0};
+	int ret;
+
+	/*
+	 * Read Tap Delay values from DT, if the DT does not contain the
+	 * Tap Values then use the pre-defined values.
+	 */
+	ret = of_property_read_u32_array(np, prop, &clk_phase[0], 2);
+	if (ret < 0) {
+		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 Clock Delay values from DT
+ *
+ * @dev:		Pointer to our struct device.
+ * @clk_data:		Pointer to the Clock Data structure
+ *
+ * Called at initialization to parse the values of Clock Delays.
+ */
+static void arasan_dt_parse_clk_phases(struct device *dev,
+				       struct sdhci_arasan_clk_data *clk_data)
+{
+	u32 mio_bank = 0;
+	int i;
+
+	/*
+	 * This has been kept as a pointer and is assigned a function here.
+	 * So that different controller variants can assign their own handling
+	 * function.
+	 */
+	clk_data->set_clk_delays = sdhci_arasan_set_clk_delays;
+
+	if (of_device_is_compatible(dev->of_node, "xlnx,zynqmp-8.9a")) {
+		u32 zynqmp_iclk_phase[ZYNQMP_CLK_PHASES + 1] = ZYNQMP_ICLK_PHASE;
+		u32 zynqmp_oclk_phase[ZYNQMP_CLK_PHASES + 1] = ZYNQMP_OCLK_PHASE;
+
+		of_property_read_u32(dev->of_node, "xlnx,mio-bank", &mio_bank);
+		if (mio_bank == 2) {
+			zynqmp_oclk_phase[ZYNQMP_CLK_PHASE_UHS_SDR104] = 90;
+			zynqmp_oclk_phase[ZYNQMP_CLK_PHASE_HS200] = 90;
+		}
+
+		for (i = 0; i <= ZYNQMP_CLK_PHASES; i++) {
+			clk_data->clk_phase_in[i] = zynqmp_iclk_phase[i];
+			clk_data->clk_phase_out[i] = zynqmp_oclk_phase[i];
+		}
+	}
+
+	arasan_dt_read_clk_phase(dev, clk_data, MMC_TIMING_LEGACY,
+				 "clk-phase-legacy");
+	arasan_dt_read_clk_phase(dev, clk_data, MMC_TIMING_MMC_HS,
+				 "clk-phase-mmc-hs");
+	arasan_dt_read_clk_phase(dev, clk_data, MMC_TIMING_SD_HS,
+				 "clk-phase-sd-hs");
+	arasan_dt_read_clk_phase(dev, clk_data, MMC_TIMING_UHS_SDR12,
+				 "clk-phase-uhs-sdr12");
+	arasan_dt_read_clk_phase(dev, clk_data, MMC_TIMING_UHS_SDR25,
+				 "clk-phase-uhs-sdr25");
+	arasan_dt_read_clk_phase(dev, clk_data, MMC_TIMING_UHS_SDR50,
+				 "clk-phase-uhs-sdr50");
+	arasan_dt_read_clk_phase(dev, clk_data, MMC_TIMING_UHS_SDR104,
+				 "clk-phase-uhs-sdr104");
+	arasan_dt_read_clk_phase(dev, clk_data, MMC_TIMING_UHS_DDR50,
+				 "clk-phase-uhs-ddr50");
+	arasan_dt_read_clk_phase(dev, clk_data, MMC_TIMING_MMC_DDR52,
+				 "clk-phase-mmc-ddr52");
+	arasan_dt_read_clk_phase(dev, clk_data, MMC_TIMING_MMC_HS200,
+				 "clk-phase-mmc-hs200");
+	arasan_dt_read_clk_phase(dev, clk_data, MMC_TIMING_MMC_HS400,
+				 "clk-phase-mmc-hs400");
+}
+
 static int arasan_sdhci_probe(struct device *dev)
 {
 	struct device_node *np = dev->of_node;
@@ -281,6 +400,8 @@ static int arasan_sdhci_probe(struct device *dev)
 	mci->f_max = clk_get_rate(clk_xin);
 	mci->f_min = 50000000 / 256;
 
+	arasan_dt_parse_clk_phases(dev, &arasan_sdhci->clk_data);
+
 	/* parse board supported bus width capabilities */
 	mci_of_parse(&arasan_sdhci->mci);
 

-- 
2.40.1