diff mbox series

[v3,1/2] mmc: sdhci-of-at91: factor out clks and presets setting

Message ID 20170713080418.12048-1-quentin.schulz@free-electrons.com
State Accepted
Commit c8a019e7e12e1d450b5fd8e5bfb180b5a8004d9f
Headers show
Series [v3,1/2] mmc: sdhci-of-at91: factor out clks and presets setting | expand

Commit Message

Quentin Schulz July 13, 2017, 8:04 a.m. UTC
The setting of clocks and presets is currently done in probe only but
once deep PM support is added, it'll be needed in the resume function.

Let's create a function for this setting.

Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com>

Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>

Acked-by: Adrian Hunter <adrian.hunter@intel.com>

---
 drivers/mmc/host/sdhci-of-at91.c | 147 ++++++++++++++++++++++-----------------
 1 file changed, 82 insertions(+), 65 deletions(-)

-- 
2.11.0

Comments

Ulf Hansson July 13, 2017, 10:06 a.m. UTC | #1
On 13 July 2017 at 10:04, Quentin Schulz
<quentin.schulz@free-electrons.com> wrote:
> This adds deepest (Backup+Self-Refresh) PM support to the ATMEL SAMA5D2

> SoC's SDHCI controller.

>

> When resuming from deepest state, it is required to restore preset

> registers as the registers are lost since VDD core has been shut down

> when entering deepest state on the SAMA5D2. The clocks need to be

> reconfigured as well.

>

> The other registers and init process are taken care of by the SDHCI

> core.

>

> Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com>

> Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>


Thanks, applied for next!

Kind regards
Uffe


> ---

>

> v3:

>   - pm_runtime_force_suspend before setting restore_needed flag,

>

> v2:

>   - use runtime_resume as system_resume,

>   - set a flag to tell when restoring presets is needed,

>   - use a flag to tell runtime_resume to restore presets,

>   - surround sdhci_at91_suspend with ifdef CONFIG_PM_SLEEP instead of CONFIG_PM,

>

>  drivers/mmc/host/sdhci-of-at91.c | 32 ++++++++++++++++++++++++++++++--

>  1 file changed, 30 insertions(+), 2 deletions(-)

>

> diff --git a/drivers/mmc/host/sdhci-of-at91.c b/drivers/mmc/host/sdhci-of-at91.c

> index fb8c6011f13d..88e9b5f35a62 100644

> --- a/drivers/mmc/host/sdhci-of-at91.c

> +++ b/drivers/mmc/host/sdhci-of-at91.c

> @@ -41,6 +41,7 @@ struct sdhci_at91_priv {

>         struct clk *hclock;

>         struct clk *gck;

>         struct clk *mainck;

> +       bool restore_needed;

>  };

>

>  static void sdhci_at91_set_clock(struct sdhci_host *host, unsigned int clock)

> @@ -206,6 +207,22 @@ static int sdhci_at91_set_clks_presets(struct device *dev)

>         return 0;

>  }

>

> +#ifdef CONFIG_PM_SLEEP

> +static int sdhci_at91_suspend(struct device *dev)

> +{

> +       struct sdhci_host *host = dev_get_drvdata(dev);

> +       struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);

> +       struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host);

> +       int ret;

> +

> +       ret = pm_runtime_force_suspend(dev);

> +

> +       priv->restore_needed = true;

> +

> +       return ret;

> +}

> +#endif /* CONFIG_PM_SLEEP */

> +

>  #ifdef CONFIG_PM

>  static int sdhci_at91_runtime_suspend(struct device *dev)

>  {

> @@ -233,6 +250,15 @@ static int sdhci_at91_runtime_resume(struct device *dev)

>         struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host);

>         int ret;

>

> +       if (priv->restore_needed) {

> +               ret = sdhci_at91_set_clks_presets(dev);

> +               if (ret)

> +                       return ret;

> +

> +               priv->restore_needed = false;

> +               goto out;

> +       }

> +

>         ret = clk_prepare_enable(priv->mainck);

>         if (ret) {

>                 dev_err(dev, "can't enable mainck\n");

> @@ -251,13 +277,13 @@ static int sdhci_at91_runtime_resume(struct device *dev)

>                 return ret;

>         }

>

> +out:

>         return sdhci_runtime_resume_host(host);

>  }

>  #endif /* CONFIG_PM */

>

>  static const struct dev_pm_ops sdhci_at91_dev_pm_ops = {

> -       SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,

> -                               pm_runtime_force_resume)

> +       SET_SYSTEM_SLEEP_PM_OPS(sdhci_at91_suspend, pm_runtime_force_resume)

>         SET_RUNTIME_PM_OPS(sdhci_at91_runtime_suspend,

>                            sdhci_at91_runtime_resume,

>                            NULL)

> @@ -306,6 +332,8 @@ static int sdhci_at91_probe(struct platform_device *pdev)

>         if (ret)

>                 goto sdhci_pltfm_free;

>

> +       priv->restore_needed = false;

> +

>         ret = mmc_of_parse(host->mmc);

>         if (ret)

>                 goto clocks_disable_unprepare;

> --

> 2.11.0

>
diff mbox series

Patch

diff --git a/drivers/mmc/host/sdhci-of-at91.c b/drivers/mmc/host/sdhci-of-at91.c
index 7611fd679f1a..fb8c6011f13d 100644
--- a/drivers/mmc/host/sdhci-of-at91.c
+++ b/drivers/mmc/host/sdhci-of-at91.c
@@ -128,6 +128,84 @@  static const struct of_device_id sdhci_at91_dt_match[] = {
 };
 MODULE_DEVICE_TABLE(of, sdhci_at91_dt_match);
 
+static int sdhci_at91_set_clks_presets(struct device *dev)
+{
+	struct sdhci_host *host = dev_get_drvdata(dev);
+	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+	struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host);
+	int ret;
+	unsigned int			caps0, caps1;
+	unsigned int			clk_base, clk_mul;
+	unsigned int			gck_rate, real_gck_rate;
+	unsigned int			preset_div;
+
+	/*
+	 * The mult clock is provided by as a generated clock by the PMC
+	 * controller. In order to set the rate of gck, we have to get the
+	 * base clock rate and the clock mult from capabilities.
+	 */
+	clk_prepare_enable(priv->hclock);
+	caps0 = readl(host->ioaddr + SDHCI_CAPABILITIES);
+	caps1 = readl(host->ioaddr + SDHCI_CAPABILITIES_1);
+	clk_base = (caps0 & SDHCI_CLOCK_V3_BASE_MASK) >> SDHCI_CLOCK_BASE_SHIFT;
+	clk_mul = (caps1 & SDHCI_CLOCK_MUL_MASK) >> SDHCI_CLOCK_MUL_SHIFT;
+	gck_rate = clk_base * 1000000 * (clk_mul + 1);
+	ret = clk_set_rate(priv->gck, gck_rate);
+	if (ret < 0) {
+		dev_err(dev, "failed to set gck");
+		clk_disable_unprepare(priv->hclock);
+		return ret;
+	}
+	/*
+	 * We need to check if we have the requested rate for gck because in
+	 * some cases this rate could be not supported. If it happens, the rate
+	 * is the closest one gck can provide. We have to update the value
+	 * of clk mul.
+	 */
+	real_gck_rate = clk_get_rate(priv->gck);
+	if (real_gck_rate != gck_rate) {
+		clk_mul = real_gck_rate / (clk_base * 1000000) - 1;
+		caps1 &= (~SDHCI_CLOCK_MUL_MASK);
+		caps1 |= ((clk_mul << SDHCI_CLOCK_MUL_SHIFT) &
+			  SDHCI_CLOCK_MUL_MASK);
+		/* Set capabilities in r/w mode. */
+		writel(SDMMC_CACR_KEY | SDMMC_CACR_CAPWREN,
+		       host->ioaddr + SDMMC_CACR);
+		writel(caps1, host->ioaddr + SDHCI_CAPABILITIES_1);
+		/* Set capabilities in ro mode. */
+		writel(0, host->ioaddr + SDMMC_CACR);
+		dev_info(dev, "update clk mul to %u as gck rate is %u Hz\n",
+			 clk_mul, real_gck_rate);
+	}
+
+	/*
+	 * We have to set preset values because it depends on the clk_mul
+	 * value. Moreover, SDR104 is supported in a degraded mode since the
+	 * maximum sd clock value is 120 MHz instead of 208 MHz. For that
+	 * reason, we need to use presets to support SDR104.
+	 */
+	preset_div = DIV_ROUND_UP(real_gck_rate, 24000000) - 1;
+	writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div,
+	       host->ioaddr + SDHCI_PRESET_FOR_SDR12);
+	preset_div = DIV_ROUND_UP(real_gck_rate, 50000000) - 1;
+	writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div,
+	       host->ioaddr + SDHCI_PRESET_FOR_SDR25);
+	preset_div = DIV_ROUND_UP(real_gck_rate, 100000000) - 1;
+	writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div,
+	       host->ioaddr + SDHCI_PRESET_FOR_SDR50);
+	preset_div = DIV_ROUND_UP(real_gck_rate, 120000000) - 1;
+	writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div,
+	       host->ioaddr + SDHCI_PRESET_FOR_SDR104);
+	preset_div = DIV_ROUND_UP(real_gck_rate, 50000000) - 1;
+	writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div,
+	       host->ioaddr + SDHCI_PRESET_FOR_DDR50);
+
+	clk_prepare_enable(priv->mainck);
+	clk_prepare_enable(priv->gck);
+
+	return 0;
+}
+
 #ifdef CONFIG_PM
 static int sdhci_at91_runtime_suspend(struct device *dev)
 {
@@ -192,11 +270,7 @@  static int sdhci_at91_probe(struct platform_device *pdev)
 	struct sdhci_host		*host;
 	struct sdhci_pltfm_host		*pltfm_host;
 	struct sdhci_at91_priv		*priv;
-	unsigned int			caps0, caps1;
-	unsigned int			clk_base, clk_mul;
-	unsigned int			gck_rate, real_gck_rate;
 	int				ret;
-	unsigned int			preset_div;
 
 	match = of_match_device(sdhci_at91_dt_match, &pdev->dev);
 	if (!match)
@@ -228,66 +302,9 @@  static int sdhci_at91_probe(struct platform_device *pdev)
 		return PTR_ERR(priv->gck);
 	}
 
-	/*
-	 * The mult clock is provided by as a generated clock by the PMC
-	 * controller. In order to set the rate of gck, we have to get the
-	 * base clock rate and the clock mult from capabilities.
-	 */
-	clk_prepare_enable(priv->hclock);
-	caps0 = readl(host->ioaddr + SDHCI_CAPABILITIES);
-	caps1 = readl(host->ioaddr + SDHCI_CAPABILITIES_1);
-	clk_base = (caps0 & SDHCI_CLOCK_V3_BASE_MASK) >> SDHCI_CLOCK_BASE_SHIFT;
-	clk_mul = (caps1 & SDHCI_CLOCK_MUL_MASK) >> SDHCI_CLOCK_MUL_SHIFT;
-	gck_rate = clk_base * 1000000 * (clk_mul + 1);
-	ret = clk_set_rate(priv->gck, gck_rate);
-	if (ret < 0) {
-		dev_err(&pdev->dev, "failed to set gck");
-		goto hclock_disable_unprepare;
-	}
-	/*
-	 * We need to check if we have the requested rate for gck because in
-	 * some cases this rate could be not supported. If it happens, the rate
-	 * is the closest one gck can provide. We have to update the value
-	 * of clk mul.
-	 */
-	real_gck_rate = clk_get_rate(priv->gck);
-	if (real_gck_rate != gck_rate) {
-		clk_mul = real_gck_rate / (clk_base * 1000000) - 1;
-		caps1 &= (~SDHCI_CLOCK_MUL_MASK);
-		caps1 |= ((clk_mul << SDHCI_CLOCK_MUL_SHIFT) & SDHCI_CLOCK_MUL_MASK);
-		/* Set capabilities in r/w mode. */
-		writel(SDMMC_CACR_KEY | SDMMC_CACR_CAPWREN, host->ioaddr + SDMMC_CACR);
-		writel(caps1, host->ioaddr + SDHCI_CAPABILITIES_1);
-		/* Set capabilities in ro mode. */
-		writel(0, host->ioaddr + SDMMC_CACR);
-		dev_info(&pdev->dev, "update clk mul to %u as gck rate is %u Hz\n",
-			 clk_mul, real_gck_rate);
-	}
-
-	/*
-	 * We have to set preset values because it depends on the clk_mul
-	 * value. Moreover, SDR104 is supported in a degraded mode since the
-	 * maximum sd clock value is 120 MHz instead of 208 MHz. For that
-	 * reason, we need to use presets to support SDR104.
-	 */
-	preset_div = DIV_ROUND_UP(real_gck_rate, 24000000) - 1;
-	writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div,
-	       host->ioaddr + SDHCI_PRESET_FOR_SDR12);
-	preset_div = DIV_ROUND_UP(real_gck_rate, 50000000) - 1;
-	writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div,
-	       host->ioaddr + SDHCI_PRESET_FOR_SDR25);
-	preset_div = DIV_ROUND_UP(real_gck_rate, 100000000) - 1;
-	writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div,
-	       host->ioaddr + SDHCI_PRESET_FOR_SDR50);
-	preset_div = DIV_ROUND_UP(real_gck_rate, 120000000) - 1;
-	writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div,
-	       host->ioaddr + SDHCI_PRESET_FOR_SDR104);
-	preset_div = DIV_ROUND_UP(real_gck_rate, 50000000) - 1;
-	writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div,
-	       host->ioaddr + SDHCI_PRESET_FOR_DDR50);
-
-	clk_prepare_enable(priv->mainck);
-	clk_prepare_enable(priv->gck);
+	ret = sdhci_at91_set_clks_presets(&pdev->dev);
+	if (ret)
+		goto sdhci_pltfm_free;
 
 	ret = mmc_of_parse(host->mmc);
 	if (ret)
@@ -335,8 +352,8 @@  static int sdhci_at91_probe(struct platform_device *pdev)
 clocks_disable_unprepare:
 	clk_disable_unprepare(priv->gck);
 	clk_disable_unprepare(priv->mainck);
-hclock_disable_unprepare:
 	clk_disable_unprepare(priv->hclock);
+sdhci_pltfm_free:
 	sdhci_pltfm_free(pdev);
 	return ret;
 }