mmc: sdhci: Workaround broken command queuing on Intel GLK

Command queuing has been reported broken on some Lenovo systems based on
Intel GLK. This is likely a BIOS issue, so disable command queuing for
Intel GLK if the BIOS vendor string is "LENOVO".

Fixes: 8ee82bda230f ("mmc: sdhci-pci: Add CQHCI support for Intel GLK")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20191217095349.14592-1-adrian.hunter@intel.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

diff --git a/drivers/mmc/host/sdhci-pci-core.c b/drivers/mmc/host/sdhci-pci-core.c
index acefb76..5091e2c 100644 (file)
--- a/drivers/mmc/host/sdhci-pci-core.c
+++ b/drivers/mmc/host/sdhci-pci-core.c
@@ -27,6 +27,7 @@
 #include <linux/mmc/slot-gpio.h>
 #include <linux/mmc/sdhci-pci-data.h>
 #include <linux/acpi.h>
+#include <linux/dmi.h>
 
 #ifdef CONFIG_X86
 #include <asm/iosf_mbi.h>
@@ -783,11 +784,18 @@ static int byt_emmc_probe_slot(struct sdhci_pci_slot *slot)
        return 0;
 }
 
+static bool glk_broken_cqhci(struct sdhci_pci_slot *slot)
+{
+       return slot->chip->pdev->device == PCI_DEVICE_ID_INTEL_GLK_EMMC &&
+              dmi_match(DMI_BIOS_VENDOR, "LENOVO");
+}
+
 static int glk_emmc_probe_slot(struct sdhci_pci_slot *slot)
 {
        int ret = byt_emmc_probe_slot(slot);
 
-       slot->host->mmc->caps2 |= MMC_CAP2_CQE;
+       if (!glk_broken_cqhci(slot))
+               slot->host->mmc->caps2 |= MMC_CAP2_CQE;
 
        if (slot->chip->pdev->device != PCI_DEVICE_ID_INTEL_GLK_EMMC) {
                slot->host->mmc->caps2 |= MMC_CAP2_HS400_ES,