From: Ye Li <ye.li@nxp.com>
Date: Thu, 24 Oct 2019 02:27:48 +0000 (-0700)
Subject: MLK-22851-1 mmc: fsl_esdhc: reduce unnecessary clock change
X-Git-Tag: rel_imx_4.19.35_1.1.0~5
X-Git-Url: https://git.somdevices.com/?a=commitdiff_plain;h=18d62cf12e4c736d1a7cf2c9e7404ba0cac270fa;p=u-boot.git

MLK-22851-1 mmc: fsl_esdhc: reduce unnecessary clock change

In mmc initial state, the mmc framework sets clock to 0, so the fsl_esdhc
driver converts to use min clock 400Khz. But the priv->clock is logged
400Khz not 0, and cause following calls to set_ios to set clock again.

Each set to clock has 10ms delay for stable, then the problem accumulates
some unnecessary delay.

Signed-off-by: Ye Li <ye.li@nxp.com>
(cherry picked from commit 151ab3bef2b1ec1c142c31048f3005ebce2a7a18)
---

diff --git a/drivers/mmc/fsl_esdhc.c b/drivers/mmc/fsl_esdhc.c
index 5d09b3ffba..78e1a60bc5 100644
--- a/drivers/mmc/fsl_esdhc.c
+++ b/drivers/mmc/fsl_esdhc.c
@@ -636,9 +636,6 @@ static void set_sysctl(struct fsl_esdhc_priv *priv, struct mmc *mmc, uint clock)
 		sdhc_clk >>= 1;
 	}
 
-	if (clock < mmc->cfg->f_min)
-		clock = mmc->cfg->f_min;
-
 	if (sdhc_clk / 16 > clock) {
 		for (; pre_div < 256; pre_div *= 2)
 			if ((sdhc_clk / pre_div) <= (clock * 16))
@@ -971,6 +968,7 @@ static int esdhc_set_ios_common(struct fsl_esdhc_priv *priv, struct mmc *mmc)
 {
 	struct fsl_esdhc *regs = priv->esdhc_regs;
 	int ret __maybe_unused;
+	uint clock;
 
 #ifdef CONFIG_FSL_ESDHC_USE_PERIPHERAL_CLK
 	/* Select to use peripheral clock */
@@ -979,8 +977,12 @@ static int esdhc_set_ios_common(struct fsl_esdhc_priv *priv, struct mmc *mmc)
 	esdhc_clock_control(priv, true);
 #endif
 	/* Set the clock speed */
-	if (priv->clock != mmc->clock)
-		set_sysctl(priv, mmc, mmc->clock);
+	clock = mmc->clock;
+	if (clock < mmc->cfg->f_min)
+		clock = mmc->cfg->f_min;
+
+	if (priv->clock != clock)
+		set_sysctl(priv, mmc, clock);
 
 #ifdef MMC_SUPPORTS_TUNING
 	if (mmc->clk_disable) {