[PATCH 2/2] mmc: sdhci-of-arasan: Add support for eMMC5.1 on Xilinx Versal Net platform

From: Sai Krishna Potthuri
Date: Fri Mar 24 2023 - 03:37:31 EST


From: Swati Agarwal <swati.agarwal@xxxxxxx>

Add support for eMMC5.1 on Xilinx Versal Net platform
- Add new compatible string(xlnx,versal-net-5.1-emmc).
- Add support for PHY which is part of Host Controller register space.
- Add DLL and Delay Chain mode support and corresponding tap delays for
all eMMC modes.
- Add Strobe select tap for HS400 mode.

Signed-off-by: Swati Agarwal <swati.agarwal@xxxxxxx>
Co-developed-by: Sai Krishna Potthuri <sai.krishna.potthuri@xxxxxxx>
Signed-off-by: Sai Krishna Potthuri <sai.krishna.potthuri@xxxxxxx>
---
drivers/mmc/host/sdhci-of-arasan.c | 237 ++++++++++++++++++++++++++++-
1 file changed, 236 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c
index deb67daf179f..2d53bd7af44b 100644
--- a/drivers/mmc/host/sdhci-of-arasan.c
+++ b/drivers/mmc/host/sdhci-of-arasan.c
@@ -41,11 +41,41 @@
#define VENDOR_ENHANCED_STROBE BIT(0)

#define PHY_CLK_TOO_SLOW_HZ 400000
+#define MIN_PHY_CLK_HZ 50000000

#define SDHCI_ITAPDLY_CHGWIN 0x200
#define SDHCI_ITAPDLY_ENABLE 0x100
#define SDHCI_OTAPDLY_ENABLE 0x40

+#define PHY_CTRL_REG1 0x270
+#define PHY_CTRL_ITAPDLY_ENA_MASK BIT(0)
+#define PHY_CTRL_ITAPDLY_SEL_MASK GENMASK(5, 1)
+#define PHY_CTRL_ITAPDLY_SEL_SHIFT 1
+#define PHY_CTRL_ITAP_CHG_WIN_MASK BIT(6)
+#define PHY_CTRL_OTAPDLY_ENA_MASK BIT(8)
+#define PHY_CTRL_OTAPDLY_SEL_MASK GENMASK(15, 12)
+#define PHY_CTRL_OTAPDLY_SEL_SHIFT 12
+#define PHY_CTRL_STRB_SEL_MASK GENMASK(23, 16)
+#define PHY_CTRL_STRB_SEL_SHIFT 16
+#define PHY_CTRL_TEST_CTRL_MASK GENMASK(31, 24)
+
+#define PHY_CTRL_REG2 0x274
+#define PHY_CTRL_EN_DLL_MASK BIT(0)
+#define PHY_CTRL_DLL_RDY_MASK BIT(1)
+#define PHY_CTRL_FREQ_SEL_MASK GENMASK(6, 4)
+#define PHY_CTRL_FREQ_SEL_SHIFT 4
+#define PHY_CTRL_SEL_DLY_TX_MASK BIT(16)
+#define PHY_CTRL_SEL_DLY_RX_MASK BIT(17)
+#define FREQSEL_200M_170M 0x0
+#define FREQSEL_170M_140M 0x1
+#define FREQSEL_140M_110M 0x2
+#define FREQSEL_110M_80M 0x3
+#define FREQSEL_80M_50M 0x4
+#define FREQSEL_275M_250M 0x5
+#define FREQSEL_250M_225M 0x6
+#define FREQSEL_225M_200M 0x7
+#define PHY_DLL_TIMEOUT_MS 100
+
/* 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}
@@ -53,6 +83,11 @@
#define VERSAL_ICLK_PHASE {0, 132, 132, 0, 132, 0, 0, 162, 90, 0, 0}
#define VERSAL_OCLK_PHASE {0, 60, 48, 0, 48, 72, 90, 36, 60, 90, 0}

+#define VERSAL_NET_EMMC_ICLK_PHASE {0, 0, 0, 0, 0, 0, 0, 0, 39, 0, 0}
+#define VERSAL_NET_EMMC_OCLK_PHASE {0, 113, 0, 0, 0, 0, 0, 0, 113, 79, 45}
+
+#define VERSAL_NET_PHY_CTRL_STRB90_STRB180_VAL 0X77
+
/*
* On some SoCs the syscon area has a feature where the upper 16-bits of
* each 32-bit register act as a write mask for the lower 16-bits. This allows
@@ -135,6 +170,7 @@ struct sdhci_arasan_clk_data {
* @clk_ahb: Pointer to the AHB clock
* @phy: Pointer to the generic phy
* @is_phy_on: True if the PHY is on; false if not.
+ * @internal_phy_reg: True if the PHY is within the Host controller.
* @has_cqe: True if controller has command queuing engine.
* @clk_data: Struct for the Arasan Controller Clock Data.
* @clk_ops: Struct for the Arasan Controller Clock Operations.
@@ -147,6 +183,7 @@ struct sdhci_arasan_data {
struct clk *clk_ahb;
struct phy *phy;
bool is_phy_on;
+ bool internal_phy_reg;

bool has_cqe;
struct sdhci_arasan_clk_data clk_data;
@@ -207,6 +244,61 @@ static const struct sdhci_arasan_soc_ctl_map intel_keembay_soc_ctl_map = {
.hiword_update = false,
};

+static void sdhci_arasan_phy_set_delaychain(struct sdhci_host *host, bool enable)
+{
+ u32 reg;
+
+ reg = readl(host->ioaddr + PHY_CTRL_REG2);
+ if (enable)
+ reg |= (PHY_CTRL_SEL_DLY_TX_MASK | PHY_CTRL_SEL_DLY_RX_MASK);
+ else
+ reg &= ~(PHY_CTRL_SEL_DLY_TX_MASK | PHY_CTRL_SEL_DLY_RX_MASK);
+
+ writel(reg, host->ioaddr + PHY_CTRL_REG2);
+}
+
+static int sdhci_arasan_phy_set_dll(struct sdhci_host *host, bool enable)
+{
+ u32 reg;
+
+ reg = readl(host->ioaddr + PHY_CTRL_REG2);
+ if (enable)
+ reg |= PHY_CTRL_EN_DLL_MASK;
+ else
+ reg &= ~PHY_CTRL_EN_DLL_MASK;
+
+ writel(reg, host->ioaddr + PHY_CTRL_REG2);
+
+ if (!enable)
+ return 0;
+
+ return readl_relaxed_poll_timeout(host->ioaddr + PHY_CTRL_REG2, reg,
+ (reg & PHY_CTRL_DLL_RDY_MASK), 10,
+ 1000 * PHY_DLL_TIMEOUT_MS);
+}
+
+static void sdhci_arasan_phy_dll_set_freq(struct sdhci_host *host, int clock)
+{
+ u32 reg, freq_sel, freq;
+
+ freq = DIV_ROUND_CLOSEST(clock, 1000000);
+ if (freq <= 200 && freq > 170)
+ freq_sel = FREQSEL_200M_170M;
+ else if (freq <= 170 && freq > 140)
+ freq_sel = FREQSEL_170M_140M;
+ else if (freq <= 140 && freq > 110)
+ freq_sel = FREQSEL_140M_110M;
+ else if (freq <= 110 && freq > 80)
+ freq_sel = FREQSEL_110M_80M;
+ else
+ freq_sel = FREQSEL_80M_50M;
+
+ reg = readl(host->ioaddr + PHY_CTRL_REG2);
+ reg &= ~PHY_CTRL_FREQ_SEL_MASK;
+ reg |= (freq_sel << PHY_CTRL_FREQ_SEL_SHIFT);
+ writel(reg, host->ioaddr + PHY_CTRL_REG2);
+}
+
/**
* sdhci_arasan_syscon_write - Write to a field in soc_ctl registers
*
@@ -321,11 +413,24 @@ static void sdhci_arasan_set_clock(struct sdhci_host *host, unsigned int clock)
}

/* Set the Input and Output Clock Phase Delays */
- if (clk_data->set_clk_delays)
+ if (clk_data->set_clk_delays && clock > PHY_CLK_TOO_SLOW_HZ)
clk_data->set_clk_delays(host);

+ if (sdhci_arasan->internal_phy_reg && clock >= MIN_PHY_CLK_HZ) {
+ sdhci_writew(host, 0, SDHCI_CLOCK_CONTROL);
+ sdhci_arasan_phy_set_dll(host, 0);
+ sdhci_arasan_phy_set_delaychain(host, 0);
+ sdhci_arasan_phy_dll_set_freq(host, clock);
+ } else if (sdhci_arasan->internal_phy_reg) {
+ sdhci_writew(host, 0, SDHCI_CLOCK_CONTROL);
+ sdhci_arasan_phy_set_delaychain(host, 1);
+ }
+
sdhci_set_clock(host, clock);

+ if (sdhci_arasan->internal_phy_reg && clock >= MIN_PHY_CLK_HZ)
+ sdhci_arasan_phy_set_dll(host, 1);
+
if (sdhci_arasan->quirks & SDHCI_ARASAN_QUIRK_CLOCK_UNSTABLE)
/*
* Some controllers immediately report SDHCI_CLOCK_INT_STABLE
@@ -897,6 +1002,101 @@ static const struct clk_ops versal_sampleclk_ops = {
.set_phase = sdhci_versal_sampleclk_set_phase,
};

+static int sdhci_versal_net_emmc_sdcardclk_set_phase(struct clk_hw *hw, int degrees)
+{
+ struct sdhci_arasan_clk_data *clk_data =
+ container_of(hw, struct sdhci_arasan_clk_data, sdcardclk_hw);
+ struct sdhci_arasan_data *sdhci_arasan =
+ container_of(clk_data, struct sdhci_arasan_data, clk_data);
+ struct sdhci_host *host = sdhci_arasan->host;
+ u8 tap_delay, tap_max = 0;
+
+ switch (host->timing) {
+ case MMC_TIMING_MMC_HS:
+ case MMC_TIMING_MMC_DDR52:
+ tap_max = 16;
+ break;
+ case MMC_TIMING_MMC_HS200:
+ case MMC_TIMING_MMC_HS400:
+ /* For 200MHz clock, 32 Taps are available */
+ tap_max = 32;
+ break;
+ default:
+ break;
+ }
+
+ tap_delay = (degrees * tap_max) / 360;
+
+ /* Set the Clock Phase */
+ if (tap_delay) {
+ u32 regval;
+
+ regval = sdhci_readl(host, PHY_CTRL_REG1);
+ regval |= PHY_CTRL_OTAPDLY_ENA_MASK;
+ sdhci_writel(host, regval, PHY_CTRL_REG1);
+ regval &= ~PHY_CTRL_OTAPDLY_SEL_MASK;
+ regval |= tap_delay << PHY_CTRL_OTAPDLY_SEL_SHIFT;
+ sdhci_writel(host, regval, PHY_CTRL_REG1);
+ }
+
+ return 0;
+}
+
+static const struct clk_ops versal_net_sdcardclk_ops = {
+ .recalc_rate = sdhci_arasan_sdcardclk_recalc_rate,
+ .set_phase = sdhci_versal_net_emmc_sdcardclk_set_phase,
+};
+
+static int sdhci_versal_net_emmc_sampleclk_set_phase(struct clk_hw *hw, int degrees)
+{
+ struct sdhci_arasan_clk_data *clk_data =
+ container_of(hw, struct sdhci_arasan_clk_data, sampleclk_hw);
+ struct sdhci_arasan_data *sdhci_arasan =
+ container_of(clk_data, struct sdhci_arasan_data, clk_data);
+ struct sdhci_host *host = sdhci_arasan->host;
+ u8 tap_delay, tap_max = 0;
+ u32 regval;
+
+ switch (host->timing) {
+ case MMC_TIMING_MMC_HS:
+ case MMC_TIMING_MMC_DDR52:
+ tap_max = 32;
+ break;
+ case MMC_TIMING_MMC_HS400:
+ /* Strobe select tap point for strb90 and strb180 */
+ regval = sdhci_readl(host, PHY_CTRL_REG1);
+ regval &= ~PHY_CTRL_STRB_SEL_MASK;
+ regval |= VERSAL_NET_PHY_CTRL_STRB90_STRB180_VAL << PHY_CTRL_STRB_SEL_SHIFT;
+ sdhci_writel(host, regval, PHY_CTRL_REG1);
+ break;
+ default:
+ break;
+ }
+
+ tap_delay = (degrees * tap_max) / 360;
+
+ /* Set the Clock Phase */
+ if (tap_delay) {
+ regval = sdhci_readl(host, PHY_CTRL_REG1);
+ regval |= PHY_CTRL_ITAP_CHG_WIN_MASK;
+ sdhci_writel(host, regval, PHY_CTRL_REG1);
+ regval |= PHY_CTRL_ITAPDLY_ENA_MASK;
+ sdhci_writel(host, regval, PHY_CTRL_REG1);
+ regval &= ~PHY_CTRL_ITAPDLY_SEL_MASK;
+ regval |= tap_delay << PHY_CTRL_ITAPDLY_SEL_SHIFT;
+ sdhci_writel(host, regval, PHY_CTRL_REG1);
+ regval &= ~PHY_CTRL_ITAP_CHG_WIN_MASK;
+ sdhci_writel(host, regval, PHY_CTRL_REG1);
+ }
+
+ return 0;
+}
+
+static const struct clk_ops versal_net_sampleclk_ops = {
+ .recalc_rate = sdhci_arasan_sampleclk_recalc_rate,
+ .set_phase = sdhci_versal_net_emmc_sampleclk_set_phase,
+};
+
static void arasan_zynqmp_dll_reset(struct sdhci_host *host, u32 deviceid)
{
u16 clk;
@@ -1107,7 +1307,17 @@ static void arasan_dt_parse_clk_phases(struct device *dev,
clk_data->clk_phase_out[i] = versal_oclk_phase[i];
}
}
+ if (of_device_is_compatible(dev->of_node, "xlnx,versal-net-5.1-emmc")) {
+ u32 versal_net_iclk_phase[MMC_TIMING_MMC_HS400 + 1] =
+ VERSAL_NET_EMMC_ICLK_PHASE;
+ u32 versal_net_oclk_phase[MMC_TIMING_MMC_HS400 + 1] =
+ VERSAL_NET_EMMC_OCLK_PHASE;

+ for (i = 0; i <= MMC_TIMING_MMC_HS400; i++) {
+ clk_data->clk_phase_in[i] = versal_net_iclk_phase[i];
+ clk_data->clk_phase_out[i] = versal_net_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,
@@ -1225,6 +1435,14 @@ static const struct sdhci_pltfm_data sdhci_arasan_zynqmp_pdata = {
SDHCI_QUIRK2_STOP_WITH_TC,
};

+static const struct sdhci_pltfm_data sdhci_arasan_versal_net_pdata = {
+ .ops = &sdhci_arasan_ops,
+ .quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN |
+ SDHCI_QUIRK2_CLOCK_DIV_ZERO_BROKEN |
+ SDHCI_QUIRK2_STOP_WITH_TC |
+ SDHCI_QUIRK2_CAPS_BIT63_FOR_HS400,
+};
+
static const struct sdhci_arasan_clk_ops zynqmp_clk_ops = {
.sdcardclk_ops = &zynqmp_sdcardclk_ops,
.sampleclk_ops = &zynqmp_sampleclk_ops,
@@ -1245,6 +1463,16 @@ static struct sdhci_arasan_of_data sdhci_arasan_versal_data = {
.clk_ops = &versal_clk_ops,
};

+static const struct sdhci_arasan_clk_ops versal_net_clk_ops = {
+ .sdcardclk_ops = &versal_net_sdcardclk_ops,
+ .sampleclk_ops = &versal_net_sampleclk_ops,
+};
+
+static struct sdhci_arasan_of_data sdhci_arasan_versal_net_data = {
+ .pdata = &sdhci_arasan_versal_net_pdata,
+ .clk_ops = &versal_net_clk_ops,
+};
+
static struct sdhci_arasan_of_data intel_keembay_emmc_data = {
.soc_ctl_map = &intel_keembay_soc_ctl_map,
.pdata = &sdhci_keembay_emmc_pdata,
@@ -1314,6 +1542,10 @@ static const struct of_device_id sdhci_arasan_of_match[] = {
.compatible = "xlnx,versal-8.9a",
.data = &sdhci_arasan_versal_data,
},
+ {
+ .compatible = "xlnx,versal-net-5.1-emmc",
+ .data = &sdhci_arasan_versal_net_data,
+ },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, sdhci_arasan_of_match);
@@ -1788,6 +2020,9 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
host->mmc->caps2 |= MMC_CAP2_CQE_DCMD;
}

+ if (of_device_is_compatible(np, "xlnx,versal-net-5.1-emmc"))
+ sdhci_arasan->internal_phy_reg = true;
+
ret = sdhci_arasan_add_host(sdhci_arasan);
if (ret)
goto err_add_host;
--
2.25.1