SDHC controller in AMD chipsets require SDHC transfer mode
register to be cleared for commands without data. The issue was
uncovered during testing eMMC cards on KB/ML based platforms
Signed-off-by: Vincent Wan <vincent.wan@xxxxxxx>
Signed-off-by: Wan Zongshun <mcuos.com@xxxxxxxxx>
Signed-off-by: Arindam Nath <arindam.nath@xxxxxxx>
Tested-by: Vikram B <vikram.b@xxxxxxx>
Tested-by: Raghavendra Swamy <raghavendra.swamy@xxxxxxx>
---
drivers/mmc/host/sdhci.c | 9 +++++++--
include/linux/mmc/sdhci.h | 2 ++
2 files changed, 9 insertions(+), 2 deletions(-)
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index f895ab0..a743d52 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -915,10 +915,15 @@ static void sdhci_set_transfer_mode(struct sdhci_host *host,
struct mmc_data *data = cmd->data;
if (data == NULL) {
+ if (host->quirks2 &
+ SDHCI_QUIRK2_CLEAR_TRANSFERMODE_REG_BEFORE_CMD) {
+ sdhci_writew(host, 0x0, SDHCI_TRANSFER_MODE);
+ } else {
/* clear Auto CMD settings for no data CMDs */
- mode = sdhci_readw(host, SDHCI_TRANSFER_MODE);
- sdhci_writew(host, mode & ~(SDHCI_TRNS_AUTO_CMD12 |
+ mode = sdhci_readw(host, SDHCI_TRANSFER_MODE);
+ sdhci_writew(host, mode & ~(SDHCI_TRNS_AUTO_CMD12 |
SDHCI_TRNS_AUTO_CMD23), SDHCI_TRANSFER_MODE);
+ }
return;
}
diff --git a/include/linux/mmc/sdhci.h b/include/linux/mmc/sdhci.h
index 931ac5e..ae7f357 100644
--- a/include/linux/mmc/sdhci.h
+++ b/include/linux/mmc/sdhci.h
@@ -102,6 +102,8 @@ struct sdhci_host {
#define SDHCI_QUIRK2_STOP_WITH_TC (1<<8)
/* Controller does not support 64-bit DMA */
#define SDHCI_QUIRK2_BROKEN_64_BIT_DMA (1<<9)
+/* need clear transfer mode register before send cmd */
+#define SDHCI_QUIRK2_CLEAR_TRANSFERMODE_REG_BEFORE_CMD (1<<10)
int irq; /* Device IRQ */
void __iomem *ioaddr; /* Mapped address */
--
1.8.1.2
--
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