[v3,1/3] add a new quirk for SDHCI host

Commit Message

Chuanxiao.Dong Dec. 2, 2010, 11:25 a.m. UTC

None

Patch

diff --git a/drivers/mmc/card/queue.c b/drivers/mmc/card/queue.c
index 4e42d03..f557788 100644
--- a/drivers/mmc/card/queue.c
+++ b/drivers/mmc/card/queue.c
@@ -131,7 +131,10 @@  int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card, spinlock_t *lock
 	queue_flag_set_unlocked(QUEUE_FLAG_NONROT, mq->queue);
 	if (mmc_can_erase(card)) {
 		queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, mq->queue);
-		mq->queue->limits.max_discard_sectors = UINT_MAX;
+		/* get a suitable max_discard_sectors limitation */
+		mq->queue->limits.max_discard_sectors =
+			mmc_set_discard_limit(card);
+
 		if (card->erased_byte == 0)
 			mq->queue->limits.discard_zeroes_data = 1;
 		if (!mmc_can_trim(card) && is_power_of_2(card->erase_size)) {
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 6286898..9fe16c2 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -1469,6 +1469,39 @@  int mmc_erase_group_aligned(struct mmc_card *card, unsigned int from,
 }
 EXPORT_SYMBOL(mmc_erase_group_aligned);
 
+/**
+ * mmc_set_discard_limit: set the max_discard_sectors according
+ * to host controller erase capability.
+ * @card: card need to be erased
+ *
+ * Return value:
+ * positive value: one erase block size
+ * UINT_MAX: unlimitied value which means no limitation for
+ * max_discard_sectors
+ */
+int mmc_set_discard_limit(struct mmc_card *card)
+{
+	struct mmc_host *host;
+	unsigned int nr = UINT_MAX;
+	host = card->host;
+	if (host->caps & MMC_CAP_ERASE_SINGLE) {
+		/*
+		 * Have to set a small limitation for request queue
+		 * to ensure that host controller won't generate a
+		 * timeout interrupt during erasing, here let limitation
+		 * to be one erase block size.
+		 * And this will let TRIM/ERASE performance lower.
+		 */
+		nr = 1;
+		if (card->erase_shift)
+			nr <<= card->erase_shift;
+		else
+			nr *= card->erase_size;
+	}
+	return nr;
+}
+EXPORT_SYMBOL(mmc_set_discard_limit);
+
 int mmc_set_blocklen(struct mmc_card *card, unsigned int blocklen)
 {
 	struct mmc_command cmd;
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 8a74fcb..b4448a9 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1875,6 +1875,10 @@  int sdhci_add_host(struct sdhci_host *host)
 
 	mmc->f_max = host->max_clk;
 	mmc->caps |= MMC_CAP_SDIO_IRQ;
+	mmc->caps |= MMC_CAP_ERASE;
+
+	if (host->quirks & SDHCI_QUIRK_FORCE_ERASE_SINGLE)
+		mmc->caps |= MMC_CAP_ERASE_SINGLE;
 
 	/*
 	 * A controller may support 8-bit width, but the board itself
diff --git a/include/linux/mmc/core.h b/include/linux/mmc/core.h
index 64e013f..ffddd1f 100644
--- a/include/linux/mmc/core.h
+++ b/include/linux/mmc/core.h
@@ -152,6 +152,7 @@  extern int mmc_can_trim(struct mmc_card *card);
 extern int mmc_can_secure_erase_trim(struct mmc_card *card);
 extern int mmc_erase_group_aligned(struct mmc_card *card, unsigned int from,
 				   unsigned int nr);
+extern int mmc_set_discard_limit(struct mmc_card *card);
 
 extern int mmc_set_blocklen(struct mmc_card *card, unsigned int blocklen);
 
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 381c77f..c3d2ade 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -169,6 +169,8 @@  struct mmc_host {
 #define MMC_CAP_1_2V_DDR	(1 << 12)	/* can support */
 						/* DDR mode at 1.2V */
 #define MMC_CAP_POWER_OFF_CARD	(1 << 13)	/* Can power off after boot */
+#define MMC_CAP_ERASE_SINGLE	(1 << 14)
+				/* Erase signle erase block each time */
 
 	mmc_pm_flag_t		pm_caps;	/* supported pm features */
 
diff --git a/include/linux/mmc/sdhci.h b/include/linux/mmc/sdhci.h
index 1fdc673..e7bdfc8 100644
--- a/include/linux/mmc/sdhci.h
+++ b/include/linux/mmc/sdhci.h
@@ -83,6 +83,8 @@  struct sdhci_host {
 #define SDHCI_QUIRK_MULTIBLOCK_READ_ACMD12		(1<<28)
 /* Controller doesn't have HISPD bit field in HI-SPEED SD card */
 #define SDHCI_QUIRK_NO_HISPD_BIT			(1<<29)
+/* Controller has an issue with erase/trim the whole device at one time */
+#define SDHCI_QUIRK_FORCE_ERASE_SINGLE			(1<<30)
 
 	int irq;		/* Device IRQ */
 	void __iomem *ioaddr;	/* Mapped address */