[PATCH v6 10/14] mmc: sdhci-xenon: Add SoC PHY PAD voltage control

From: Gregory CLEMENT
Date: Tue Feb 14 2017 - 12:04:49 EST


From: Hu Ziji <huziji@xxxxxxxxxxx>

Some SoCs have PHY PAD outside Xenon IP.
PHY PAD voltage should match signalling voltage in use.

Add generic SoC PHY PAD voltage control interface.
Implement Aramda-3700 SoC PHY PAD voltage control.

Signed-off-by: Hu Ziji <huziji@xxxxxxxxxxx>
Tested-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxx>
Signed-off-by: Gregory CLEMENT <gregory.clement@xxxxxxxxxxxxxxxxxx>
---
drivers/mmc/host/sdhci-xenon-phy.c | 116 +++++++++++++++++++++++++++++-
drivers/mmc/host/sdhci-xenon.c | 2 +-
drivers/mmc/host/sdhci-xenon.h | 2 +-
3 files changed, 119 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/sdhci-xenon-phy.c b/drivers/mmc/host/sdhci-xenon-phy.c
index c26ba3a180a0..c3b7e9a21f6b 100644
--- a/drivers/mmc/host/sdhci-xenon-phy.c
+++ b/drivers/mmc/host/sdhci-xenon-phy.c
@@ -143,6 +143,27 @@ enum phy_type_enum {
NR_PHY_TYPES
};

+enum soc_pad_ctrl_type {
+ SOC_PAD_SD,
+ SOC_PAD_FIXED_1_8V,
+};
+
+struct soc_pad_ctrl_table {
+ const char *soc;
+ void (*set_soc_pad)(struct sdhci_host *host,
+ unsigned char signal_voltage);
+};
+
+struct soc_pad_ctrl {
+ /* Register address of SoC PHY PAD ctrl */
+ void __iomem *reg;
+ /* SoC PHY PAD ctrl type */
+ enum soc_pad_ctrl_type pad_type;
+ /* SoC specific operation to set SoC PHY PAD */
+ void (*set_soc_pad)(struct sdhci_host *host,
+ unsigned char signal_voltage);
+};
+
static struct xenon_emmc_phy_regs xenon_emmc_5_0_phy_regs = {
.timing_adj = XENON_EMMC_5_0_PHY_TIMING_ADJUST,
.func_ctrl = XENON_EMMC_5_0_PHY_FUNC_CONTROL,
@@ -176,6 +197,8 @@ struct emmc_phy_params {
u8 nr_tun_times;
/* Divider for calculating Tuning Step */
u8 tun_step_divider;
+
+ struct soc_pad_ctrl pad_ctrl;
};

static int alloc_emmc_phy(struct sdhci_xenon_priv *priv)
@@ -252,6 +275,45 @@ static int emmc_phy_init(struct sdhci_host *host)
return 0;
}

+#define ARMADA_3700_SOC_PAD_1_8V 0x1
+#define ARMADA_3700_SOC_PAD_3_3V 0x0
+
+static void armada_3700_soc_pad_voltage_set(struct sdhci_host *host,
+ unsigned char signal_voltage)
+{
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct sdhci_xenon_priv *priv = sdhci_pltfm_priv(pltfm_host);
+ struct emmc_phy_params *params = priv->phy_params;
+
+ if (params->pad_ctrl.pad_type == SOC_PAD_FIXED_1_8V) {
+ writel(ARMADA_3700_SOC_PAD_1_8V, params->pad_ctrl.reg);
+ } else if (params->pad_ctrl.pad_type == SOC_PAD_SD) {
+ if (signal_voltage == MMC_SIGNAL_VOLTAGE_180)
+ writel(ARMADA_3700_SOC_PAD_1_8V, params->pad_ctrl.reg);
+ else if (signal_voltage == MMC_SIGNAL_VOLTAGE_330)
+ writel(ARMADA_3700_SOC_PAD_3_3V, params->pad_ctrl.reg);
+ }
+}
+
+/*
+ * Set SoC PHY voltage PAD control register,
+ * according to the operation voltage on PAD.
+ * The detailed operation depends on SoC implementation.
+ */
+static void emmc_phy_set_soc_pad(struct sdhci_host *host,
+ unsigned char signal_voltage)
+{
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct sdhci_xenon_priv *priv = sdhci_pltfm_priv(pltfm_host);
+ struct emmc_phy_params *params = priv->phy_params;
+
+ if (!params->pad_ctrl.reg)
+ return;
+
+ if (params->pad_ctrl.set_soc_pad)
+ params->pad_ctrl.set_soc_pad(host, signal_voltage);
+}
+
/*
* Enable eMMC PHY HW DLL
* DLL should be enabled and stable before HS200/SDR104 tuning,
@@ -584,6 +646,51 @@ static void emmc_phy_set(struct sdhci_host *host,
dev_dbg(mmc_dev(host->mmc), "eMMC PHY setting completes\n");
}

+static int get_dt_pad_ctrl_data(struct sdhci_host *host,
+ struct device_node *np,
+ struct emmc_phy_params *params)
+{
+ int ret = 0;
+ const char *name;
+ struct resource iomem;
+
+ if (of_device_is_compatible(np, "marvell,armada-3700-sdhci"))
+ params->pad_ctrl.set_soc_pad = armada_3700_soc_pad_voltage_set;
+ else
+ return 0;
+
+ if (of_address_to_resource(np, 1, &iomem)) {
+ dev_err(mmc_dev(host->mmc), "Unable to find SoC PAD ctrl register address for %s\n",
+ np->name);
+ return -EINVAL;
+ }
+
+ params->pad_ctrl.reg = devm_ioremap_resource(mmc_dev(host->mmc),
+ &iomem);
+ if (IS_ERR(params->pad_ctrl.reg)) {
+ dev_err(mmc_dev(host->mmc), "Unable to get SoC PHY PAD ctrl register for %s\n",
+ np->name);
+ return PTR_ERR(params->pad_ctrl.reg);
+ }
+
+ ret = of_property_read_string(np, "marvell,pad-type", &name);
+ if (ret) {
+ dev_err(mmc_dev(host->mmc), "Unable to determine SoC PHY PAD ctrl type\n");
+ return ret;
+ }
+ if (!strcmp(name, "sd")) {
+ params->pad_ctrl.pad_type = SOC_PAD_SD;
+ } else if (!strcmp(name, "fixed-1-8v")) {
+ params->pad_ctrl.pad_type = SOC_PAD_FIXED_1_8V;
+ } else {
+ dev_err(mmc_dev(host->mmc), "Unsupported SoC PHY PAD ctrl type %s\n",
+ name);
+ return -EINVAL;
+ }
+
+ return ret;
+}
+
static int emmc_phy_parse_param_dt(struct sdhci_host *host,
struct device_node *np,
struct emmc_phy_params *params)
@@ -617,7 +724,14 @@ static int emmc_phy_parse_param_dt(struct sdhci_host *host,
else
params->tun_step_divider = XENON_TUNING_STEP_DIVIDER;

- return 0;
+ return get_dt_pad_ctrl_data(host, np, params);
+}
+
+/* Set SoC PHY Voltage PAD */
+void xenon_soc_pad_ctrl(struct sdhci_host *host,
+ unsigned char signal_voltage)
+{
+ emmc_phy_set_soc_pad(host, signal_voltage);
}

/*
diff --git a/drivers/mmc/host/sdhci-xenon.c b/drivers/mmc/host/sdhci-xenon.c
index 99c18cad6460..f344d9fb0a1b 100644
--- a/drivers/mmc/host/sdhci-xenon.c
+++ b/drivers/mmc/host/sdhci-xenon.c
@@ -338,6 +338,8 @@ static int xenon_start_signal_voltage_switch(struct mmc_host *mmc,
*/
enable_xenon_internal_clk(host);

+ xenon_soc_pad_ctrl(host, ios->signal_voltage);
+
if (priv->init_card_type == MMC_TYPE_MMC)
return xenon_emmc_signal_voltage_switch(mmc, ios);

diff --git a/drivers/mmc/host/sdhci-xenon.h b/drivers/mmc/host/sdhci-xenon.h
index e87639774bca..57e7cb463413 100644
--- a/drivers/mmc/host/sdhci-xenon.h
+++ b/drivers/mmc/host/sdhci-xenon.h
@@ -104,4 +104,6 @@ struct sdhci_xenon_priv {
int xenon_phy_adj(struct sdhci_host *host, struct mmc_ios *ios);
int xenon_phy_parse_dt(struct device_node *np,
struct sdhci_host *host);
+void xenon_soc_pad_ctrl(struct sdhci_host *host,
+ unsigned char signal_voltage);
#endif
--
git-series 0.9.1