usb: xhci: Workaround for S3 issue on AMD SNPS 3.0 xHC

On some platform of AMD, S3 fails with HCE and SRE errors. To fix this,
need to disable a bit which is enable in sparse controller.

Cc: stable@vger.kernel.org #v4.19+
Signed-off-by: Sanket Goswami <Sanket.Goswami@amd.com>
Signed-off-by: Sandeep Singh <sandeep.singh@amd.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20201028203124.375344-3-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index c26c06e5c88cde4430100b42adc6a2d414efcf50..bf89172c43cace41449d5099653fb135c533c0e8 100644 (file)
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -23,6 +23,8 @@
 #define SSIC_PORT_CFG2_OFFSET  0x30
 #define PROG_DONE              (1 << 30)
 #define SSIC_PORT_UNUSED       (1 << 31)
+#define SPARSE_DISABLE_BIT     17
+#define SPARSE_CNTL_ENABLE     0xC12C
 
 /* Device for a quirk */
 #define PCI_VENDOR_ID_FRESCO_LOGIC     0x1b73
@@ -161,6 +163,9 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci)
            (pdev->device == 0x15e0 || pdev->device == 0x15e1))
                xhci->quirks |= XHCI_SNPS_BROKEN_SUSPEND;
 
+       if (pdev->vendor == PCI_VENDOR_ID_AMD && pdev->device == 0x15e5)
+               xhci->quirks |= XHCI_DISABLE_SPARSE;
+
        if (pdev->vendor == PCI_VENDOR_ID_AMD)
                xhci->quirks |= XHCI_TRUST_TX_LENGTH;
 
@@ -498,6 +503,15 @@ static void xhci_pme_quirk(struct usb_hcd *hcd)
        readl(reg);
 }
 
+static void xhci_sparse_control_quirk(struct usb_hcd *hcd)
+{
+       u32 reg;
+
+       reg = readl(hcd->regs + SPARSE_CNTL_ENABLE);
+       reg &= ~BIT(SPARSE_DISABLE_BIT);
+       writel(reg, hcd->regs + SPARSE_CNTL_ENABLE);
+}
+
 static int xhci_pci_suspend(struct usb_hcd *hcd, bool do_wakeup)
 {
        struct xhci_hcd *xhci = hcd_to_xhci(hcd);
@@ -517,6 +531,9 @@ static int xhci_pci_suspend(struct usb_hcd *hcd, bool do_wakeup)
        if (xhci->quirks & XHCI_SSIC_PORT_UNUSED)
                xhci_ssic_port_unused_quirk(hcd, true);
 
+       if (xhci->quirks & XHCI_DISABLE_SPARSE)
+               xhci_sparse_control_quirk(hcd);
+
        ret = xhci_suspend(xhci, do_wakeup);
        if (ret && (xhci->quirks & XHCI_SSIC_PORT_UNUSED))
                xhci_ssic_port_unused_quirk(hcd, false);

diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 8be88379c0fb232bc306bd8ebcde7e23fae1fd16..ebb359ebb261c180e17cb1ee2c44ba6ee350999c 100644 (file)
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1877,6 +1877,7 @@ struct xhci_hcd {
 #define XHCI_SNPS_BROKEN_SUSPEND    BIT_ULL(35)
 #define XHCI_RENESAS_FW_QUIRK  BIT_ULL(36)
 #define XHCI_SKIP_PHY_INIT     BIT_ULL(37)
+#define XHCI_DISABLE_SPARSE    BIT_ULL(38)
 
        unsigned int            num_active_eps;
        unsigned int            limit_active_eps;