bcm2835-mmc: Add option to disable delays on some writeb calls

raspberrypi · May 1, 2015 · aa6b3e6 · aa6b3e6
1 parent 67fd2c5
commit aa6b3e6
Showing 1 changed file with 21 additions and 8 deletions.
diff --git a/drivers/mmc/host/bcm2835-mmc.c b/drivers/mmc/host/bcm2835-mmc.c
@@ -240,15 +240,24 @@ static inline void bcm2835_mmc_writew(struct bcm2835_host *host, u16 val, int re
 
 }
 
-static inline void bcm2835_mmc_writeb(struct bcm2835_host *host, u8 val, int reg)
+static inline void bcm2835_mmc_writeb(struct bcm2835_host *host, u8 val, int reg, int from)
 {
 	u32 oldval = bcm2835_mmc_readl(host, reg & ~3);
 	u32 byte_num = reg & 3;
 	u32 byte_shift = byte_num * 8;
 	u32 mask = 0xff << byte_shift;
 	u32 newval = (oldval & ~mask) | (val << byte_shift);
 
-	bcm2835_mmc_writel(host, newval, reg & ~3, 1);
+        if ((reg & ~3) == 0x28) // SDHCI_HOST_CONTROL, SDHCI_POWER_CONTROL, SDHCI_BLOCK_GAP_CONTROL, SDHCI_WAKE_UP_CONTROL
+        {
+		WARN_ON(oldval & ((1<<16)|(1<<17)));
+        }
+        else if ((reg & ~3) == 0x2C) // SDHCI_CLOCK_CONTROL, SDHCI_TIMEOUT_CONTROL, SDHCI_SOFTWARE_RESET
+        {
+		WARN_ON(oldval & ((1<<24)|(1<<25)|(1<<26)));
+        }
+
+	bcm2835_mmc_writel(host, newval, reg & ~3, from + 10);
 }
 
 
@@ -333,7 +342,7 @@ static void bcm2835_mmc_reset(struct bcm2835_host *host, u8 mask)
 {
 	unsigned long timeout;
 
-	bcm2835_mmc_writeb(host, mask, SDHCI_SOFTWARE_RESET);
+	bcm2835_mmc_writeb(host, mask, SDHCI_SOFTWARE_RESET, 0);
 
 	if (mask & SDHCI_RESET_ALL)
 		host->clock = 0;
@@ -347,7 +356,7 @@ static void bcm2835_mmc_reset(struct bcm2835_host *host, u8 mask)
 			pr_err("%s: Reset 0x%x never completed.\n",
 				mmc_hostname(host->mmc), (int)mask);
 			bcm2835_mmc_dumpregs(host);
-			return;
+			goto exit;
 		}
 		timeout--;
 		mdelay(1);
@@ -357,6 +366,9 @@ static void bcm2835_mmc_reset(struct bcm2835_host *host, u8 mask)
 		host->max_delay = 100-timeout;
 		pr_warning("Warning: MMC controller hung for %d ms\n", host->max_delay);
 	}
+exit:
+	if ((mmc_debug & (1<<15)))
+		bcm2835_mmc_writeb(host, TIMEOUT_VAL, SDHCI_TIMEOUT_CONTROL, 1);
 }
 
 static void bcm2835_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios);
@@ -609,9 +621,10 @@ static void bcm2835_mmc_prepare_data(struct bcm2835_host *host, struct mmc_comma
 
 	WARN_ON(host->data);
 
+	if (!(mmc_debug & (1<<14)))
 	if (data || (cmd->flags & MMC_RSP_BUSY)) {
 		count = TIMEOUT_VAL;
-		bcm2835_mmc_writeb(host, count, SDHCI_TIMEOUT_CONTROL);
+		bcm2835_mmc_writeb(host, count, SDHCI_TIMEOUT_CONTROL, 1);
 	}
 
 	if (!data)
@@ -1237,7 +1250,7 @@ static void bcm2835_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 
 	if (host->pwr != SDHCI_POWER_330) {
 		host->pwr = SDHCI_POWER_330;
-		bcm2835_mmc_writeb(host, SDHCI_POWER_330 | SDHCI_POWER_ON, SDHCI_POWER_CONTROL);
+		bcm2835_mmc_writeb(host, SDHCI_POWER_330 | SDHCI_POWER_ON, SDHCI_POWER_CONTROL, 2);
 	}
 
 	ctrl = bcm2835_mmc_readb(host, SDHCI_HOST_CONTROL);
@@ -1252,7 +1265,7 @@ static void bcm2835_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 	ctrl &= ~SDHCI_CTRL_HISPD; /* NO_HISPD_BIT */
 
 
-	bcm2835_mmc_writeb(host, ctrl, SDHCI_HOST_CONTROL);
+	bcm2835_mmc_writeb(host, ctrl, SDHCI_HOST_CONTROL, 3);
 	/*
 	 * We only need to set Driver Strength if the
 	 * preset value enable is not set.
@@ -1273,7 +1286,7 @@ static void bcm2835_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 
 	/* Re-enable SD Clock */
 	bcm2835_mmc_set_clock(host, host->clock);
-	bcm2835_mmc_writeb(host, ctrl, SDHCI_HOST_CONTROL);
+	bcm2835_mmc_writeb(host, ctrl, SDHCI_HOST_CONTROL, 4);
 
 	mmiowb();