[06/12] mmc: sdhci_omap: Add support to set IODELAY values
diff mbox

Message ID 20171214130941.26666-7-kishon@ti.com
State New
Headers show

Commit Message

Kishon Vijay Abraham I Dec. 14, 2017, 1:09 p.m. UTC
The data manual of J6/J6 Eco recommends to set different IODELAY values
depending on the mode in which the MMC/SD is enumerated in order to
ensure IO timings are met.

Add support to set the IODELAY values depending on the various MMC
modes using the pinctrl APIs.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
---
 drivers/mmc/host/sdhci-omap.c | 174 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 174 insertions(+)

Comments

Tony Lindgren Dec. 14, 2017, 3:04 p.m. UTC | #1
Hi,

* Kishon Vijay Abraham I <kishon@ti.com> [171214 13:13]:
> The data manual of J6/J6 Eco recommends to set different IODELAY values
> depending on the mode in which the MMC/SD is enumerated in order to
> ensure IO timings are met.
> 
> Add support to set the IODELAY values depending on the various MMC
> modes using the pinctrl APIs.
...

> --- a/drivers/mmc/host/sdhci-omap.c
> +++ b/drivers/mmc/host/sdhci-omap.c
> @@ -105,6 +109,20 @@ struct sdhci_omap_host {
>  	struct sdhci_host	*host;
>  	u8			bus_mode;
>  	u8			power_mode;
> +	u8			timing;
> +	u8			flags;
> +
> +	struct pinctrl		*pinctrl;
> +	struct pinctrl_state	*pinctrl_state;
> +	struct pinctrl_state	*default_pinctrl_state;
> +	struct pinctrl_state	*sdr104_pinctrl_state;
> +	struct pinctrl_state	*hs200_1_8v_pinctrl_state;
> +	struct pinctrl_state	*ddr50_pinctrl_state;
> +	struct pinctrl_state	*sdr50_pinctrl_state;
> +	struct pinctrl_state	*sdr25_pinctrl_state;
> +	struct pinctrl_state	*sdr12_pinctrl_state;
> +	struct pinctrl_state	*hs_pinctrl_state;
> +	struct pinctrl_state	*ddr_1_8v_pinctrl_state;
>  };


You can make the pinctrl code more generic by allocating an array
of states and have just:

	struct pinctrl_state **pinctrl_state;

Then access it with omap_host->pinctrl_state[MMC_TIMING_MMC_HS200]
and so on.

This way the code gets simplified and you can do a generic function
to initialize things and call it from a for loop etc.

Just remember that pinctrl use can be optional as the pins can be
set up in the bootloader alone. Then you can just continue with the
default iodelay state like we are currently doing.

Regards,

Tony
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Patch
diff mbox

diff --git a/drivers/mmc/host/sdhci-omap.c b/drivers/mmc/host/sdhci-omap.c
index b20f4c79ccc6..594e41200d8a 100644
--- a/drivers/mmc/host/sdhci-omap.c
+++ b/drivers/mmc/host/sdhci-omap.c
@@ -93,8 +93,12 @@ 
 
 #define MAX_PHASE_DELAY		0x7C
 
+/* sdhci-omap controller flags */
+#define SDHCI_OMAP_REQUIRE_IODELAY	BIT(0)
+
 struct sdhci_omap_data {
 	u32 offset;
+	u8 flags;
 };
 
 struct sdhci_omap_host {
@@ -105,6 +109,20 @@  struct sdhci_omap_host {
 	struct sdhci_host	*host;
 	u8			bus_mode;
 	u8			power_mode;
+	u8			timing;
+	u8			flags;
+
+	struct pinctrl		*pinctrl;
+	struct pinctrl_state	*pinctrl_state;
+	struct pinctrl_state	*default_pinctrl_state;
+	struct pinctrl_state	*sdr104_pinctrl_state;
+	struct pinctrl_state	*hs200_1_8v_pinctrl_state;
+	struct pinctrl_state	*ddr50_pinctrl_state;
+	struct pinctrl_state	*sdr50_pinctrl_state;
+	struct pinctrl_state	*sdr25_pinctrl_state;
+	struct pinctrl_state	*sdr12_pinctrl_state;
+	struct pinctrl_state	*hs_pinctrl_state;
+	struct pinctrl_state	*ddr_1_8v_pinctrl_state;
 };
 
 static void sdhci_omap_start_clock(struct sdhci_omap_host *omap_host);
@@ -449,6 +467,62 @@  static int sdhci_omap_start_signal_voltage_switch(struct mmc_host *mmc,
 	return 0;
 }
 
+static void sdhci_omap_set_timing(struct sdhci_omap_host *omap_host, u8 timing)
+{
+	int ret;
+	struct pinctrl_state *pinctrl_state;
+	struct device *dev = omap_host->dev;
+
+	if (omap_host->timing == timing)
+		return;
+
+	sdhci_omap_stop_clock(omap_host);
+
+	switch (timing) {
+	case MMC_TIMING_UHS_SDR104:
+		pinctrl_state = omap_host->sdr104_pinctrl_state;
+		break;
+	case MMC_TIMING_MMC_HS200:
+		pinctrl_state = omap_host->hs200_1_8v_pinctrl_state;
+		break;
+	case MMC_TIMING_UHS_DDR50:
+		pinctrl_state = omap_host->ddr50_pinctrl_state;
+		break;
+	case MMC_TIMING_UHS_SDR50:
+		pinctrl_state = omap_host->sdr50_pinctrl_state;
+		break;
+	case MMC_TIMING_UHS_SDR25:
+		pinctrl_state = omap_host->sdr25_pinctrl_state;
+		break;
+	case MMC_TIMING_UHS_SDR12:
+		pinctrl_state = omap_host->sdr12_pinctrl_state;
+		break;
+	case MMC_TIMING_SD_HS:
+	case MMC_TIMING_MMC_HS:
+		pinctrl_state = omap_host->hs_pinctrl_state;
+		break;
+	case MMC_TIMING_MMC_DDR52:
+		pinctrl_state = omap_host->ddr_1_8v_pinctrl_state;
+		break;
+	default:
+		pinctrl_state = omap_host->default_pinctrl_state;
+		break;
+	}
+
+	if (omap_host->flags & SDHCI_OMAP_REQUIRE_IODELAY) {
+		ret = pinctrl_select_state(omap_host->pinctrl, pinctrl_state);
+		if (ret) {
+			dev_err(dev, "failed to select pinctrl state\n");
+			goto ret;
+		}
+		omap_host->pinctrl_state = pinctrl_state;
+	}
+
+ret:
+	sdhci_omap_start_clock(omap_host);
+	omap_host->timing = timing;
+}
+
 static void sdhci_omap_set_power_mode(struct sdhci_omap_host *omap_host,
 				      u8 power_mode)
 {
@@ -485,6 +559,7 @@  static void sdhci_omap_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 	omap_host = sdhci_pltfm_priv(pltfm_host);
 
 	sdhci_omap_set_bus_mode(omap_host, ios->bus_mode);
+	sdhci_omap_set_timing(omap_host, ios->timing);
 	sdhci_set_ios(mmc, ios);
 	sdhci_omap_set_power_mode(omap_host, ios->power_mode);
 }
@@ -693,6 +768,7 @@  static const struct sdhci_pltfm_data sdhci_omap_pdata = {
 
 static const struct sdhci_omap_data dra7_data = {
 	.offset = 0x200,
+	.flags	= SDHCI_OMAP_REQUIRE_IODELAY,
 };
 
 static const struct of_device_id omap_sdhci_match[] = {
@@ -701,6 +777,98 @@  static const struct of_device_id omap_sdhci_match[] = {
 };
 MODULE_DEVICE_TABLE(of, omap_sdhci_match);
 
+static struct pinctrl_state
+*sdhci_omap_iodelay_pinctrl_state(struct sdhci_omap_host *omap_host, char *mode,
+				  u32 *caps, u32 capmask)
+{
+	struct device *dev = omap_host->dev;
+	struct pinctrl_state *pinctrl_state = ERR_PTR(-ENODEV);
+
+	if (!(*caps & capmask))
+		goto ret;
+
+	pinctrl_state = pinctrl_lookup_state(omap_host->pinctrl, mode);
+	if (IS_ERR(pinctrl_state)) {
+		dev_err(dev, "no pinctrl state for %s mode", mode);
+		*caps &= ~capmask;
+	}
+
+ret:
+	return pinctrl_state;
+}
+
+static int sdhci_omap_config_iodelay_pinctrl_state(struct sdhci_omap_host
+						   *omap_host)
+{
+	struct device *dev = omap_host->dev;
+	struct sdhci_host *host = omap_host->host;
+	struct mmc_host *mmc = host->mmc;
+	u32 *caps = &mmc->caps;
+	u32 *caps2 = &mmc->caps2;
+	struct pinctrl_state *state;
+
+	if (!(omap_host->flags & SDHCI_OMAP_REQUIRE_IODELAY))
+		return 0;
+
+	omap_host->pinctrl = devm_pinctrl_get(omap_host->dev);
+	if (IS_ERR(omap_host->pinctrl)) {
+		dev_err(dev, "Cannot get pinctrl\n");
+		return PTR_ERR(omap_host->pinctrl);
+	}
+
+	state = pinctrl_lookup_state(omap_host->pinctrl, "default");
+	if (IS_ERR(state)) {
+		dev_err(dev, "no pinctrl state for default mode\n");
+		return PTR_ERR(state);
+	}
+	omap_host->default_pinctrl_state = state;
+
+	state = sdhci_omap_iodelay_pinctrl_state(omap_host, "sdr104", caps,
+						 MMC_CAP_UHS_SDR104);
+	if (!IS_ERR(state))
+		omap_host->sdr104_pinctrl_state = state;
+
+	state = sdhci_omap_iodelay_pinctrl_state(omap_host, "ddr50", caps,
+						 MMC_CAP_UHS_DDR50);
+	if (!IS_ERR(state))
+		omap_host->ddr50_pinctrl_state = state;
+
+	state = sdhci_omap_iodelay_pinctrl_state(omap_host, "sdr50", caps,
+						 MMC_CAP_UHS_SDR50);
+	if (!IS_ERR(state))
+		omap_host->sdr50_pinctrl_state = state;
+
+	state = sdhci_omap_iodelay_pinctrl_state(omap_host, "sdr25", caps,
+						 MMC_CAP_UHS_SDR25);
+	if (!IS_ERR(state))
+		omap_host->sdr25_pinctrl_state = state;
+
+	state = sdhci_omap_iodelay_pinctrl_state(omap_host, "sdr12", caps,
+						 MMC_CAP_UHS_SDR12);
+	if (!IS_ERR(state))
+		omap_host->sdr12_pinctrl_state = state;
+
+	state = sdhci_omap_iodelay_pinctrl_state(omap_host, "ddr_1_8v", caps,
+						 MMC_CAP_1_8V_DDR);
+	if (!IS_ERR(state))
+		omap_host->ddr_1_8v_pinctrl_state = state;
+
+	state = sdhci_omap_iodelay_pinctrl_state(omap_host, "hs", caps,
+						 MMC_CAP_MMC_HIGHSPEED |
+						 MMC_CAP_SD_HIGHSPEED);
+	if (!IS_ERR(state))
+		omap_host->hs_pinctrl_state = state;
+
+	state = sdhci_omap_iodelay_pinctrl_state(omap_host, "hs200_1_8v", caps2,
+						 MMC_CAP2_HS200_1_8V_SDR);
+	if (!IS_ERR(state))
+		omap_host->hs200_1_8v_pinctrl_state = state;
+
+	omap_host->pinctrl_state = omap_host->default_pinctrl_state;
+
+	return 0;
+}
+
 static int sdhci_omap_probe(struct platform_device *pdev)
 {
 	int ret;
@@ -737,6 +905,8 @@  static int sdhci_omap_probe(struct platform_device *pdev)
 	omap_host->base = host->ioaddr;
 	omap_host->dev = dev;
 	omap_host->power_mode = MMC_POWER_UNDEFINED;
+	omap_host->timing = MMC_TIMING_LEGACY;
+	omap_host->flags = data->flags;
 	host->ioaddr += offset;
 
 	mmc = host->mmc;
@@ -785,6 +955,10 @@  static int sdhci_omap_probe(struct platform_device *pdev)
 		goto err_put_sync;
 	}
 
+	ret = sdhci_omap_config_iodelay_pinctrl_state(omap_host);
+	if (ret)
+		goto err_put_sync;
+
 	host->mmc_host_ops.get_ro = mmc_gpio_get_ro;
 	host->mmc_host_ops.start_signal_voltage_switch =
 					sdhci_omap_start_signal_voltage_switch;