[U-Boot] [PATCH 07/22] mmc: use mmc modes to select the correct bus speed

Jean-Jacques Hiblot jjhiblot at ti.com
Fri May 12 18:16:25 UTC 2017


Signed-off-by: Jean-Jacques Hiblot <jjhiblot at ti.com>
---
 drivers/mmc/mmc.c | 40 +++++++++++++++++++++++++++++-----------
 1 file changed, 29 insertions(+), 11 deletions(-)

diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index 5d418c5..dc7985f 100644
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -171,9 +171,35 @@ const char *mmc_mode_name(enum bus_mode mode)
 	else
 		return names[mode];
 }
+
+static uint mmc_mode2freq(struct mmc *mmc, enum bus_mode mode)
+{
+	static const int freqs[] = {
+	      [SD_LEGACY]	= 25000000,
+	      [MMC_HS]		= 26000000,
+	      [SD_HS]		= 50000000,
+	      [UHS_SDR12]	= 25000000,
+	      [UHS_SDR25]	= 50000000,
+	      [UHS_SDR50]	= 100000000,
+	      [UHS_SDR104]	= 208000000,
+	      [UHS_DDR50]	= 50000000,
+	      [MMC_HS_52]	= 52000000,
+	      [MMC_DDR_52]	= 52000000,
+	      [MMC_HS_200]	= 200000000,
+	};
+
+	if (mode == MMC_LEGACY)
+		return mmc->legacy_speed;
+	else if (mode >= MMC_MODES_END)
+		return 0;
+	else
+		return freqs[mode];
+}
+
 static int mmc_select_mode(struct mmc *mmc, enum bus_mode mode)
 {
 	mmc->selected_mode = mode;
+	mmc->tran_speed = mmc_mode2freq(mmc, mode);
 	debug("selecting mode %s (freq : %d MHz)\n", mmc_mode_name(mode),
 	      mmc->tran_speed / 1000000);
 	return 0;
@@ -1185,13 +1211,10 @@ static int sd_select_bus_freq_width(struct mmc *mmc)
 	if (err)
 		return err;
 
-	if (mmc->card_caps & MMC_MODE_HS) {
+	if (mmc->card_caps & MMC_MODE_HS)
 		mmc_select_mode(mmc, SD_HS);
-		mmc->tran_speed = 50000000;
-	} else {
+	else
 		mmc_select_mode(mmc, SD_LEGACY);
-		mmc->tran_speed = 25000000;
-	}
 
 	return 0;
 }
@@ -1310,11 +1333,8 @@ static int mmc_select_bus_freq_width(struct mmc *mmc)
 			mmc_select_mode(mmc, MMC_DDR_52);
 		else
 			mmc_select_mode(mmc, MMC_HS_52);
-		mmc->tran_speed = 52000000;
-	} else if (mmc->card_caps & MMC_MODE_HS) {
+	} else if (mmc->card_caps & MMC_MODE_HS)
 		mmc_select_mode(mmc, MMC_HS);
-		mmc->tran_speed = 26000000;
-	}
 
 	return err;
 }
@@ -1584,7 +1604,6 @@ static int mmc_startup(struct mmc *mmc)
 	mult = multipliers[((cmd.response[0] >> 3) & 0xf)];
 
 	mmc->legacy_speed = freq * mult;
-	mmc->tran_speed = mmc->legacy_speed;
 	mmc_select_mode(mmc, MMC_LEGACY);
 
 	mmc->dsr_imp = ((cmd.response[1] >> 12) & 0x1);
@@ -1659,7 +1678,6 @@ static int mmc_startup(struct mmc *mmc)
 	if (err)
 		return err;
 
-	mmc_set_clock(mmc, mmc->tran_speed);
 
 	/* Fix the block length for DDR mode */
 	if (mmc->ddr_mode) {
-- 
1.9.1



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