mmc: core: Use CMD23 for multiblock transfers when we can.

CMD23-prefixed instead of open-ended multiblock transfers
have a performance advantage on some MMC cards.

Signed-off-by: Andrei Warkentin <andreiw@motorola.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

4 files changed, 14 insertions, 0 deletions

diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
index 7190aa2096f7..4a0e27baaea0 100644
--- a/include/linux/mmc/card.h
+++ b/include/linux/mmc/card.h
@@ -171,6 +171,7 @@ struct mmc_card {
 #define MMC_QUIRK_NONSTD_FUNC_IF (1<<4)		/* SDIO card has nonstd function interfaces */
 #define MMC_QUIRK_DISABLE_CD	(1<<5)		/* disconnect CD/DAT[3] resistor */
 #define MMC_QUIRK_INAND_CMD38	(1<<6)		/* iNAND devices have broken CMD38 */
+#define MMC_QUIRK_BLK_NO_CMD23	(1<<7)		/* Avoid CMD23 for regular multiblock */
 
 	unsigned int		erase_size;	/* erase size in sectors */
  	unsigned int		erase_shift;	/* if erase unit is power 2 */
diff --git a/include/linux/mmc/core.h b/include/linux/mmc/core.h
index cbe8d55f64c4..b6718e549a51 100644
--- a/include/linux/mmc/core.h
+++ b/include/linux/mmc/core.h
@@ -120,6 +120,7 @@ struct mmc_data {
 };
 
 struct mmc_request {
+	struct mmc_command	*sbc;		/* SET_BLOCK_COUNT for multiblock */
 	struct mmc_command	*cmd;
 	struct mmc_data		*data;
 	struct mmc_command	*stop;
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index de32e6aa018a..e946bd10fe3f 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -210,6 +210,7 @@ struct mmc_host {
 #define MMC_CAP_MAX_CURRENT_400	(1 << 27)	/* Host max current limit is 400mA */
 #define MMC_CAP_MAX_CURRENT_600	(1 << 28)	/* Host max current limit is 600mA */
 #define MMC_CAP_MAX_CURRENT_800	(1 << 29)	/* Host max current limit is 800mA */
+#define MMC_CAP_CMD23		(1 << 30)	/* CMD23 supported. */
 
 	mmc_pm_flag_t		pm_caps;	/* supported pm features */
 
@@ -366,5 +367,10 @@ static inline int mmc_card_wake_sdio_irq(struct mmc_host *host)
 {
 	return host->pm_flags & MMC_PM_WAKE_SDIO_IRQ;
 }
+
+static inline int mmc_host_cmd23(struct mmc_host *host)
+{
+	return host->caps & MMC_CAP_CMD23;
+}
 #endif
 
diff --git a/include/linux/mmc/mmc.h b/include/linux/mmc/mmc.h
index 9fa5a73f393d..ac26a685cca8 100644
--- a/include/linux/mmc/mmc.h
+++ b/include/linux/mmc/mmc.h
@@ -83,6 +83,12 @@
 #define MMC_APP_CMD              55   /* ac   [31:16] RCA        R1  */
 #define MMC_GEN_CMD              56   /* adtc [0] RD/WR          R1  */
 
+static inline bool mmc_op_multi(u32 opcode)
+{
+	return opcode == MMC_WRITE_MULTIPLE_BLOCK ||
+	       opcode == MMC_READ_MULTIPLE_BLOCK;
+}
+
 /*
  * MMC_SWITCH argument format:
  *