1 files changed, 59 insertions, 12 deletions

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 8ff37f06e..57be129fe 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -13,6 +13,7 @@
  *     - JMicron (hardware and technical support)
  */
 
+#include <linux/bitfield.h>
 #include <linux/delay.h>
 #include <linux/ktime.h>
 #include <linux/highmem.h>
@@ -263,6 +264,7 @@ static void sdhci_init(struct sdhci_host *host, int soft)
 	if (soft) {
 		/* force clock reconfiguration */
 		host->clock = 0;
+		host->reinit_uhs = true;
 		mmc->ops->set_ios(mmc, &mmc->ios);
 	}
 }
@@ -1418,10 +1420,9 @@ u16 sdhci_calc_clk(struct sdhci_host *host, unsigned int clock,
 
 			clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
 			pre_val = sdhci_get_preset_value(host);
-			div = (pre_val & SDHCI_PRESET_SDCLK_FREQ_MASK)
-				>> SDHCI_PRESET_SDCLK_FREQ_SHIFT;
+			div = FIELD_GET(SDHCI_PRESET_SDCLK_FREQ_MASK, pre_val);
 			if (host->clk_mul &&
-				(pre_val & SDHCI_PRESET_CLKGEN_SEL_MASK)) {
+				(pre_val & SDHCI_PRESET_CLKGEN_SEL)) {
 				clk = SDHCI_PROG_CLOCK_MODE;
 				real_div = div + 1;
 				clk_mul = host->clk_mul;
@@ -1736,11 +1737,46 @@ void sdhci_set_uhs_signaling(struct sdhci_host *host, unsigned timing)
 }
 EXPORT_SYMBOL_GPL(sdhci_set_uhs_signaling);
 
+static bool sdhci_timing_has_preset(unsigned char timing)
+{
+	switch (timing) {
+	case MMC_TIMING_UHS_SDR12:
+	case MMC_TIMING_UHS_SDR25:
+	case MMC_TIMING_UHS_SDR50:
+	case MMC_TIMING_UHS_SDR104:
+	case MMC_TIMING_UHS_DDR50:
+	case MMC_TIMING_MMC_DDR52:
+		return true;
+	};
+	return false;
+}
+
+static bool sdhci_preset_needed(struct sdhci_host *host, unsigned char timing)
+{
+	return !(host->quirks2 & SDHCI_QUIRK2_PRESET_VALUE_BROKEN) &&
+	       sdhci_timing_has_preset(timing);
+}
+
+static bool sdhci_presetable_values_change(struct sdhci_host *host, struct mmc_ios *ios)
+{
+	/*
+	 * Preset Values are: Driver Strength, Clock Generator and SDCLK/RCLK
+	 * Frequency. Check if preset values need to be enabled, or the Driver
+	 * Strength needs updating. Note, clock changes are handled separately.
+	 */
+	return !host->preset_enabled &&
+	       (sdhci_preset_needed(host, ios->timing) || host->drv_type != ios->drv_type);
+}
+
 void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 {
 	struct sdhci_host *host = mmc_priv(mmc);
+	bool reinit_uhs = host->reinit_uhs;
+	bool turning_on_clk = false;
 	u8 ctrl;
 
+	host->reinit_uhs = false;
+
 	if (ios->power_mode == MMC_POWER_UNDEFINED)
 		return;
 
@@ -1766,6 +1802,8 @@ void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 		sdhci_enable_preset_value(host, false);
 
 	if (!ios->clock || ios->clock != host->clock) {
+		turning_on_clk = ios->clock && !host->clock;
+
 		host->ops->set_clock(host, ios->clock);
 		host->clock = ios->clock;
 
@@ -1792,6 +1830,17 @@ void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 
 	host->ops->set_bus_width(host, ios->bus_width);
 
+	/*
+	 * Special case to avoid multiple clock changes during voltage
+	 * switching.
+	 */
+	if (!reinit_uhs &&
+	    turning_on_clk &&
+	    host->timing == ios->timing &&
+	    host->version >= SDHCI_SPEC_300 &&
+	    !sdhci_presetable_values_change(host, ios))
+		return;
+
 	ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
 
 	if (!(host->quirks & SDHCI_QUIRK_NO_HISPD_BIT)) {
@@ -1835,6 +1884,7 @@ void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 			}
 
 			sdhci_writew(host, ctrl_2, SDHCI_HOST_CONTROL2);
+			host->drv_type = ios->drv_type;
 		} else {
 			/*
 			 * According to SDHC Spec v3.00, if the Preset Value
@@ -1862,19 +1912,14 @@ void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 		host->ops->set_uhs_signaling(host, ios->timing);
 		host->timing = ios->timing;
 
-		if (!(host->quirks2 & SDHCI_QUIRK2_PRESET_VALUE_BROKEN) &&
-				((ios->timing == MMC_TIMING_UHS_SDR12) ||
-				 (ios->timing == MMC_TIMING_UHS_SDR25) ||
-				 (ios->timing == MMC_TIMING_UHS_SDR50) ||
-				 (ios->timing == MMC_TIMING_UHS_SDR104) ||
-				 (ios->timing == MMC_TIMING_UHS_DDR50) ||
-				 (ios->timing == MMC_TIMING_MMC_DDR52))) {
+		if (sdhci_preset_needed(host, ios->timing)) {
 			u16 preset;
 
 			sdhci_enable_preset_value(host, true);
 			preset = sdhci_get_preset_value(host);
-			ios->drv_type = (preset & SDHCI_PRESET_DRV_MASK)
-				>> SDHCI_PRESET_DRV_SHIFT;
+			ios->drv_type = FIELD_GET(SDHCI_PRESET_DRV_MASK,
+						  preset);
+			host->drv_type = ios->drv_type;
 		}
 
 		/* Re-enable SD Clock */
@@ -3128,6 +3173,7 @@ int sdhci_resume_host(struct sdhci_host *host)
 		sdhci_init(host, 0);
 		host->pwr = 0;
 		host->clock = 0;
+		host->reinit_uhs = true;
 		mmc->ops->set_ios(mmc, &mmc->ios);
 	} else {
 		sdhci_init(host, (host->mmc->pm_flags & MMC_PM_KEEP_POWER));
@@ -3191,6 +3237,7 @@ int sdhci_runtime_resume_host(struct sdhci_host *host)
 		/* Force clock and power re-program */
 		host->pwr = 0;
 		host->clock = 0;
+		host->reinit_uhs = true;
 		mmc->ops->start_signal_voltage_switch(mmc, &mmc->ios);
 		mmc->ops->set_ios(mmc, &mmc->ios);