From: Shinobu Uehara <shinobu.uehara.xc@xxxxxxxxxxx>
In some controllers, when performing a multiple block read of
one or two blocks, depending on the timing with which the
response register is read, the response value may not
be read properly.
MMC_CAP2_NO_MULTI_READ flags disable all multiple block read,
but, it is over-kill for this issue.
This patch adds new MMC_CAP2_2BLKS_LIMIT to use single block read
when it was two blocks.
This is additional option of MMC_CAP2_NO_MULTI_READ
[Kuninori Morimoto: tidyup for upstreaming, and cared mach-shmobile]
Signed-off-by: Shinobu Uehara <shinobu.uehara.xc@xxxxxxxxxxx>
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@xxxxxxxxxxx>
---
arch/arm/mach-shmobile/board-koelsch.c | 6 +++---
arch/arm/mach-shmobile/board-lager.c | 4 ++--
drivers/mmc/card/block.c | 19 +++++++++++++++++--
drivers/mmc/host/sh_mobile_sdhi.c | 2 +-
include/linux/mmc/host.h | 3 +++
5 files changed, 26 insertions(+), 8 deletions(-)
diff --git a/arch/arm/mach-shmobile/board-koelsch.c b/arch/arm/mach-shmobile/board-koelsch.c
index 2cd3194..4936436 100644
--- a/arch/arm/mach-shmobile/board-koelsch.c
+++ b/arch/arm/mach-shmobile/board-koelsch.c
@@ -333,7 +333,7 @@ SDHI_REGULATOR(2, RCAR_GP_PIN(7, 19), RCAR_GP_PIN(2, 26));
static struct sh_mobile_sdhi_info sdhi0_info __initdata = {
.tmio_caps = MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ |
MMC_CAP_POWER_OFF_CARD,
- .tmio_caps2 = MMC_CAP2_NO_MULTI_READ,
+ .tmio_caps2 = MMC_CAP2_NO_2BLKS_READ,
.tmio_flags = TMIO_MMC_HAS_IDLE_WAIT,
};
@@ -346,7 +346,7 @@ static struct resource sdhi0_resources[] __initdata = {
static struct sh_mobile_sdhi_info sdhi1_info __initdata = {
.tmio_caps = MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ |
MMC_CAP_POWER_OFF_CARD,
- .tmio_caps2 = MMC_CAP2_NO_MULTI_READ,
+ .tmio_caps2 = MMC_CAP2_NO_2BLKS_READ,
.tmio_flags = TMIO_MMC_HAS_IDLE_WAIT,
};
@@ -359,7 +359,7 @@ static struct resource sdhi1_resources[] __initdata = {
static struct sh_mobile_sdhi_info sdhi2_info __initdata = {
.tmio_caps = MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ |
MMC_CAP_POWER_OFF_CARD,
- .tmio_caps2 = MMC_CAP2_NO_MULTI_READ,
+ .tmio_caps2 = MMC_CAP2_NO_2BLKS_READ,
.tmio_flags = TMIO_MMC_HAS_IDLE_WAIT |
TMIO_MMC_WRPROTECT_DISABLE,
};
diff --git a/arch/arm/mach-shmobile/board-lager.c b/arch/arm/mach-shmobile/board-lager.c
index b8b2b44..ad85f9d 100644
--- a/arch/arm/mach-shmobile/board-lager.c
+++ b/arch/arm/mach-shmobile/board-lager.c
@@ -634,7 +634,7 @@ static void __init lager_add_rsnd_device(void)
static struct sh_mobile_sdhi_info sdhi0_info __initdata = {
.tmio_caps = MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ |
MMC_CAP_POWER_OFF_CARD,
- .tmio_caps2 = MMC_CAP2_NO_MULTI_READ,
+ .tmio_caps2 = MMC_CAP2_NO_2BLKS_READ,
.tmio_flags = TMIO_MMC_HAS_IDLE_WAIT |
TMIO_MMC_WRPROTECT_DISABLE,
};
@@ -648,7 +648,7 @@ static struct resource sdhi0_resources[] __initdata = {
static struct sh_mobile_sdhi_info sdhi2_info __initdata = {
.tmio_caps = MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ |
MMC_CAP_POWER_OFF_CARD,
- .tmio_caps2 = MMC_CAP2_NO_MULTI_READ,
+ .tmio_caps2 = MMC_CAP2_NO_2BLKS_READ,
.tmio_flags = TMIO_MMC_HAS_IDLE_WAIT |
TMIO_MMC_WRPROTECT_DISABLE,
};
diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
index 452782b..f3cbe37 100644
--- a/drivers/mmc/card/block.c
+++ b/drivers/mmc/card/block.c
@@ -1400,8 +1400,23 @@ static void mmc_blk_rw_rq_prep(struct mmc_queue_req *mqrq,
/* Some controllers can't do multiblock reads due to hw bugs */
if (card->host->caps2 & MMC_CAP2_NO_MULTI_READ &&
- rq_data_dir(req) == READ)
- brq->data.blocks = 1;
+ rq_data_dir(req) == READ) {
+
+ if (card->host->caps2 & MMC_CAP2_2BLKS_LIMIT) {
+ /*
+ * In some controllers, when performing a
+ * multiple block read of one or two blocks,
+ * depending on the timing with which the
+ * response register is read, the response
+ * value may not be read properly.
+ * Use single block read for this HW bug
+ */
+ if (brq->data.blocks == 2)
+ brq->data.blocks = 1;
+ } else {
+ brq->data.blocks = 1;
+ }
+ }
}
if (brq->data.blocks > 1 || do_rel_wr) {
diff --git a/drivers/mmc/host/sh_mobile_sdhi.c b/drivers/mmc/host/sh_mobile_sdhi.c
index 18cf462..90b1ee2 100644
--- a/drivers/mmc/host/sh_mobile_sdhi.c
+++ b/drivers/mmc/host/sh_mobile_sdhi.c
@@ -55,7 +55,7 @@ static const struct sh_mobile_sdhi_of_data of_rcar_gen1_compatible = {
static const struct sh_mobile_sdhi_of_data of_rcar_gen2_compatible = {
.tmio_flags = TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_WRPROTECT_DISABLE,
.capabilities = MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ,
- .capabilities2 = MMC_CAP2_NO_MULTI_READ,
+ .capabilities2 = MMC_CAP2_NO_2BLKS_READ,
};
static const struct of_device_id sh_mobile_sdhi_of_match[] = {
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 7960424..3510fba 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -266,6 +266,9 @@ struct mmc_host {
#define MMC_CAP2_BOOTPART_NOACC (1 << 0) /* Boot partition no access */
#define MMC_CAP2_FULL_PWR_CYCLE (1 << 2) /* Can do full power cycle */
#define MMC_CAP2_NO_MULTI_READ (1 << 3) /* Multiblock reads don't work */
+#define MMC_CAP2_2BLKS_LIMIT (1 << 4) /* 2 blocks limit for multi read */
+#define MMC_CAP2_NO_2BLKS_READ (MMC_CAP2_NO_MULTI_READ | \
+ MMC_CAP2_2BLKS_LIMIT)
#define MMC_CAP2_HS200_1_8V_SDR (1 << 5) /* can support */
#define MMC_CAP2_HS200_1_2V_SDR (1 << 6) /* can support */
#define MMC_CAP2_HS200 (MMC_CAP2_HS200_1_8V_SDR | \
--
1.7.9.5
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