openwrtv4/target/linux/brcm2708/patches-3.10/0020-Add-sync_after_dma-module-parameter.patch

From a30b981976f90774867ec2a60bac86ebe7244d9a Mon Sep 17 00:00:00 2001
From: popcornmix <popcornmix@gmail.com>
Date: Tue, 17 Jul 2012 00:48:27 +0100
Subject: [PATCH 020/196] Add sync_after_dma module parameter

---
 drivers/mmc/host/sdhci-bcm2708.c | 60 +++++++++++++++++++++-------------------
 1 file changed, 32 insertions(+), 28 deletions(-)

diff --git a/drivers/mmc/host/sdhci-bcm2708.c b/drivers/mmc/host/sdhci-bcm2708.c
index 7bba950..3792b9f 100644
--- a/drivers/mmc/host/sdhci-bcm2708.c
+++ b/drivers/mmc/host/sdhci-bcm2708.c
@@ -51,7 +51,6 @@
 #undef CONFIG_MMC_SDHCI_BCM2708_DMA
 #define CONFIG_MMC_SDHCI_BCM2708_DMA y
 
-#define USE_SYNC_AFTER_DMA
 #ifdef CONFIG_MMC_SDHCI_BCM2708_DMA
 /* #define CHECK_DMA_USE */
 #endif
@@ -131,6 +130,7 @@ static inline unsigned long int since_ns(hptime_t t)
 
 static bool allow_highspeed = 1;
 static int emmc_clock_freq = BCM2708_EMMC_CLOCK_FREQ;
+static bool sync_after_dma = 1;
 
 #if 0
 static void hptime_test(void)
@@ -822,34 +822,34 @@ static void sdhci_bcm2708_dma_complete_irq(struct sdhci_host *host,
 						SDHCI_INT_SPACE_AVAIL);
 		}
 	} else {
-#ifdef USE_SYNC_AFTER_DMA
-		/* On the Arasan controller the stop command (which will be
-		   scheduled after this completes) does not seem to work
-		   properly if we allow it to be issued when we are
-		   transferring data to/from the SD card.
-		   We get CRC and DEND errors unless we wait for
-		   the SD controller to finish reading/writing to the card. */
-		u32 state_mask;
-		int timeout=5000;
-
-		DBG("PDMA over - sync card\n");
-		if (data->flags & MMC_DATA_READ)
-			state_mask = SDHCI_DOING_READ;
-		else
-			state_mask = SDHCI_DOING_WRITE;
+		if (sync_after_dma) {
+			/* On the Arasan controller the stop command (which will be
+			   scheduled after this completes) does not seem to work
+			   properly if we allow it to be issued when we are
+			   transferring data to/from the SD card.
+			   We get CRC and DEND errors unless we wait for
+			   the SD controller to finish reading/writing to the card. */
+			u32 state_mask;
+			int timeout=30*5000;
+
+			DBG("PDMA over - sync card\n");
+			if (data->flags & MMC_DATA_READ)
+				state_mask = SDHCI_DOING_READ;
+			else
+				state_mask = SDHCI_DOING_WRITE;
 
-		while (0 != (sdhci_bcm2708_raw_readl(host, SDHCI_PRESENT_STATE) 
-			& state_mask) && --timeout > 0)
-		{
-			udelay(30);
-			continue;
+			while (0 != (sdhci_bcm2708_raw_readl(host, SDHCI_PRESENT_STATE) 
+				& state_mask) && --timeout > 0)
+			{
+				udelay(1);
+				continue;
+			}
+			if (timeout <= 0)
+				printk(KERN_ERR"%s: final %s to SD card still "
+				       "running\n",
+				       mmc_hostname(host->mmc),
+				       data->flags & MMC_DATA_READ? "read": "write");
 		}
-		if (timeout <= 0)
-			printk(KERN_ERR"%s: final %s to SD card still "
-			       "running\n",
-			       mmc_hostname(host->mmc),
-			       data->flags & MMC_DATA_READ? "read": "write");
-#endif
 		if (host_priv->complete) {
 			(*host_priv->complete)(host);
 			DBG("PDMA %s complete\n",
@@ -1193,7 +1193,9 @@ static int sdhci_bcm2708_probe(struct platform_device *pdev)
 		       SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
 		       SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
                SDHCI_QUIRK_MISSING_CAPS |
-               SDHCI_QUIRK_NO_HISPD_BIT;
+               SDHCI_QUIRK_NO_HISPD_BIT |
+               (sync_after_dma ? 0:SDHCI_QUIRK_MULTIBLOCK_READ_ACMD12);
+
 
 #ifdef CONFIG_MMC_SDHCI_BCM2708_DMA
 	host->flags = SDHCI_USE_PLATDMA;
@@ -1363,6 +1365,7 @@ module_exit(sdhci_drv_exit);
 
 module_param(allow_highspeed, bool, 0444);
 module_param(emmc_clock_freq, int, 0444);
+module_param(sync_after_dma, bool, 0444);
 
 MODULE_DESCRIPTION("Secure Digital Host Controller Interface platform driver");
 MODULE_AUTHOR("Broadcom <info@broadcom.com>");
@@ -1371,5 +1374,6 @@ MODULE_ALIAS("platform:"DRIVER_NAME);
 
 MODULE_PARM_DESC(allow_highspeed, "Allow high speed transfers modes");
 MODULE_PARM_DESC(emmc_clock_freq, "Specify the speed of emmc clock");
+MODULE_PARM_DESC(sync_after_dma, "Block in driver until dma complete");
 
 
-- 
1.9.1