[PATCH 1/2] mmc: sdhci-of-at91: factor out clks and presets setting
From: Quentin Schulz
Date: Fri Jun 16 2017 - 03:30:06 EST
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@xxxxxxxxxxxxxxxxxx>
---
drivers/mmc/host/sdhci-of-at91.c | 147 ++++++++++++++++++++++-----------------
1 file changed, 82 insertions(+), 65 deletions(-)
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;
}
--
2.11.0