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authorLogan Gunthorpe <logang@deltatee.com>2018-08-10 01:09:17 +0300
committerBjorn Helgaas <bhelgaas@google.com>2018-08-10 01:59:07 +0300
commit10dbc9fedcf151ab794f5e22d4f34f1eff01a08f (patch)
tree6061ec8d2ba6aa99c351c28535b10467657ead32 /drivers/pci/quirks.c
parent73c47ddef29b5869a2221e93cefdb56fd8263718 (diff)
downloadlinux-10dbc9fedcf151ab794f5e22d4f34f1eff01a08f.tar.xz
PCI: Add ACS Redirect disable quirk for Intel Sunrise Point
Intel Sunrise Point PCH hardware has an implementation of the ACS bits that does not comply with the PCIe standard. Add a device-specific quirk, pci_quirk_disable_intel_spt_pch_acs_redir() to disable ACS Redirection on this system. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> [bhelgaas: changelog, split to separate patch] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Diffstat (limited to 'drivers/pci/quirks.c')
-rw-r--r--drivers/pci/quirks.c25
1 files changed, 25 insertions, 0 deletions
diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 4f79631159eb..dc2ee0de3c6b 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -4553,6 +4553,30 @@ static int pci_quirk_enable_intel_spt_pch_acs(struct pci_dev *dev)
return 0;
}
+static int pci_quirk_disable_intel_spt_pch_acs_redir(struct pci_dev *dev)
+{
+ int pos;
+ u32 cap, ctrl;
+
+ if (!pci_quirk_intel_spt_pch_acs_match(dev))
+ return -ENOTTY;
+
+ pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS);
+ if (!pos)
+ return -ENOTTY;
+
+ pci_read_config_dword(dev, pos + PCI_ACS_CAP, &cap);
+ pci_read_config_dword(dev, pos + INTEL_SPT_ACS_CTRL, &ctrl);
+
+ ctrl &= ~(PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_EC);
+
+ pci_write_config_dword(dev, pos + INTEL_SPT_ACS_CTRL, ctrl);
+
+ pci_info(dev, "Intel SPT PCH root port workaround: disabled ACS redirect\n");
+
+ return 0;
+}
+
static const struct pci_dev_acs_ops {
u16 vendor;
u16 device;
@@ -4564,6 +4588,7 @@ static const struct pci_dev_acs_ops {
},
{ PCI_VENDOR_ID_INTEL, PCI_ANY_ID,
.enable_acs = pci_quirk_enable_intel_spt_pch_acs,
+ .disable_acs_redir = pci_quirk_disable_intel_spt_pch_acs_redir,
},
};