[PATCH v2] mmc: Add a quirk for AMD SDHC transfer mode register need to be cleared for cmd without data
From: Vincent Wan
Date: Tue Nov 04 2014 - 03:41:18 EST
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: Arindam Nath <arindam.nath@xxxxxxx>
Cc: Huang Rui <ray.huang@xxxxxxx>
Tested-by: Vikram B <vikram.b@xxxxxxx>
Tested-by: Raghavendra Swamy <raghavendra.swamy@xxxxxxx>
---
drivers/mmc/host/sdhci-pci.c | 27 +++++++++++++++++++++++++++
drivers/mmc/host/sdhci.c | 11 ++++++++---
include/linux/mmc/sdhci.h | 2 ++
3 files changed, 37 insertions(+), 3 deletions(-)
diff --git a/drivers/mmc/host/sdhci-pci.c b/drivers/mmc/host/sdhci-pci.c
index 6119297..8f5c998 100644
--- a/drivers/mmc/host/sdhci-pci.c
+++ b/drivers/mmc/host/sdhci-pci.c
@@ -645,6 +645,23 @@ static const struct sdhci_pci_fixes sdhci_rtsx = {
.probe_slot = rtsx_probe_slot,
};
+static int amd_probe(struct sdhci_pci_chip *chip)
+{
+ struct pci_dev *smbus_dev;
+
+ smbus_dev = pci_get_device(PCI_VENDOR_ID_AMD,
+ PCI_DEVICE_ID_AMD_HUDSON2_SMBUS, NULL);
+
+ if (smbus_dev && (smbus_dev->revision < 0x51))
+ chip->quirks2 |= SDHCI_QUIRK2_CLEAR_TRANSFERMODE_REG_BEFORE_CMD;
+
+ return 0;
+}
+
+static const struct sdhci_pci_fixes sdhci_amd = {
+ .probe = amd_probe,
+};
+
static const struct pci_device_id pci_ids[] = {
{
.vendor = PCI_VENDOR_ID_RICOH,
@@ -1045,6 +1062,16 @@ static const struct pci_device_id pci_ids[] = {
.driver_data = (kernel_ulong_t)&sdhci_o2,
},
+ {
+ .vendor = PCI_VENDOR_ID_AMD,
+ .device = PCI_ANY_ID,
+ .class = PCI_CLASS_SYSTEM_SDHCI << 8,
+ .class_mask = 0xFFFF00,
+ .subvendor = PCI_ANY_ID,
+ .subdevice = PCI_ANY_ID,
+ .driver_data = (kernel_ulong_t)&sdhci_amd,
+ },
+
{ /* Generic SD host controller */
PCI_DEVICE_CLASS((PCI_CLASS_SYSTEM_SDHCI << 8), 0xFFFF00)
},
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index ada1a3e..8085f26 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -889,10 +889,15 @@ static void sdhci_set_transfer_mode(struct sdhci_host *host,
struct mmc_data *data = cmd->data;
if (data == NULL) {
- /* clear Auto CMD settings for no data CMDs */
- mode = sdhci_readw(host, SDHCI_TRANSFER_MODE);
- sdhci_writew(host, mode & ~(SDHCI_TRNS_AUTO_CMD12 |
+ 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 |
SDHCI_TRNS_AUTO_CMD23), SDHCI_TRANSFER_MODE);
+ }
return;
}
diff --git a/include/linux/mmc/sdhci.h b/include/linux/mmc/sdhci.h
index dba793e..0a287aa 100644
--- a/include/linux/mmc/sdhci.h
+++ b/include/linux/mmc/sdhci.h
@@ -100,6 +100,8 @@ struct sdhci_host {
#define SDHCI_QUIRK2_BROKEN_DDR50 (1<<7)
/* Stop command (CMD12) can set Transfer Complete when not using MMC_RSP_BUSY */
#define SDHCI_QUIRK2_STOP_WITH_TC (1<<8)
+/* need clear transfer mode register before send cmd */
+#define SDHCI_QUIRK2_CLEAR_TRANSFERMODE_REG_BEFORE_CMD (1<<9)
int irq; /* Device IRQ */
void __iomem *ioaddr; /* Mapped address */
--
1.8.1.2
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/