@@ -4415,6 +4415,57 @@ static DEFINE_HANDLER(5);
static DEFINE_HANDLER(6);
static DEFINE_HANDLER(7);
+static void mtip_disable_link_opts(struct driver_data *dd, struct pci_dev *pdev)
+{
+ int pos;
+ unsigned short pcie_dev_ctrl;
+
+ pos = pci_find_capability(pdev, PCI_CAP_ID_EXP);
+ if (pos) {
+ pci_read_config_word(pdev,
+ pos + PCI_EXP_DEVCTL,
+ &pcie_dev_ctrl);
+ if (pcie_dev_ctrl & (1 << 11) ||
+ pcie_dev_ctrl & (1 << 4)) {
+ dev_info(&dd->pdev->dev,
+ "Disabling ERO/No-Snoop on bridge device %04x:%04x\n",
+ pdev->vendor, pdev->device);
+ pcie_dev_ctrl &= ~(PCI_EXP_DEVCTL_NOSNOOP_EN |
+ PCI_EXP_DEVCTL_RELAX_EN);
+ pci_write_config_word(pdev,
+ pos + PCI_EXP_DEVCTL,
+ pcie_dev_ctrl);
+ }
+ }
+}
+
+static void mtip_fix_ero_nosnoop(struct driver_data *dd, struct pci_dev *pdev)
+{
+ /*
+ * This workaround is specific to AMD/ATI chipset with a PCI upstream
+ * device with device id 0x5aXX
+ */
+ if (pdev->bus && pdev->bus->self) {
+ if (pdev->bus->self->vendor == PCI_VENDOR_ID_ATI &&
+ ((pdev->bus->self->device & 0xff00) == 0x5a00)) {
+ mtip_disable_link_opts(dd, pdev->bus->self);
+ } else {
+ /* Check further up the topology */
+ struct pci_dev *parent_dev = pdev->bus->self;
+ if (parent_dev->bus &&
+ parent_dev->bus->parent &&
+ parent_dev->bus->parent->self &&
+ parent_dev->bus->parent->self->vendor ==
+ PCI_VENDOR_ID_ATI &&
+ (parent_dev->bus->parent->self->device &
+ 0xff00) == 0x5a00) {
+ mtip_disable_link_opts(dd,
+ parent_dev->bus->parent->self);
+ }
+ }
+ }
+}
+
/*
* Called for each supported PCI device detected.
*
@@ -4566,6 +4617,8 @@ static int mtip_pci_probe(struct pci_dev *pdev,
goto block_initialize_err;
}
+ mtip_fix_ero_nosnoop(dd, pdev);
+
/* Initialize the block layer. */
rv = mtip_block_initialize(dd);
if (rv < 0) {
This is a note to let you know that I have just added a patch titled mtip32xx: Fix ERO and NoSnoop values in PCIe upstream on AMD systems to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue This patch is scheduled to be released in version 3.13.11.5. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.13.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From d4c2bd3a387071326a793a68707e8cd3d6126b9e Mon Sep 17 00:00:00 2001 From: Asai Thambi S P <asamymuthupa@micron.com> Date: Thu, 13 Mar 2014 18:45:15 -0700 Subject: mtip32xx: Fix ERO and NoSnoop values in PCIe upstream on AMD systems commit d1e714db8129a1d3670e449b87719c78e2c76f9f upstream. A hardware quirk in P320h/P420m interfere with PCIe transactions on some AMD chipsets, making P320h/P420m unusable. This workaround is to disable ERO and NoSnoop bits in the parent and root complex for normal functioning of these devices NOTE: This workaround is specific to AMD chipset with a PCIe upstream device with device id 0x5aXX Signed-off-by: Asai Thambi S P <asamymuthupa@micron.com> Signed-off-by: Sam Bradshaw <sbradshaw@micron.com> Signed-off-by: Jens Axboe <axboe@fb.com> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- drivers/block/mtip32xx/mtip32xx.c | 53 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 53 insertions(+) -- 1.9.1