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authorMika Westerberg <mika.westerberg@linux.intel.com>2022-08-16 13:20:42 +0300
committerBjorn Helgaas <bhelgaas@google.com>2022-09-28 02:13:18 +0300
commit5459c0b7046752e519a646e1c2404852bb628459 (patch)
tree6130d59b4cd245cc0e5dd0eeca3299ae1628c5cf /drivers/pci
parent568035b01cfb107af8d2e4bd2fb9aea22cf5b868 (diff)
downloadlinux-5459c0b7046752e519a646e1c2404852bb628459.tar.xz
PCI/DPC: Quirk PIO log size for certain Intel Root Ports
Some Root Ports on Intel Tiger Lake and Alder Lake systems support the RP Extensions for DPC and the RP PIO Log registers but incorrectly advertise an RP PIO Log Size of zero. This means the kernel complains that: DPC: RP PIO log size 0 is invalid and if DPC is triggered, the DPC driver will not dump the RP PIO Log registers when it should. This is caused by a BIOS bug and should be fixed the BIOS for future CPUs. Add a quirk to set the correct RP PIO Log size for the affected Root Ports. Link: https://bugzilla.kernel.org/show_bug.cgi?id=209943 Link: https://lore.kernel.org/r/20220816102042.69125-1-mika.westerberg@linux.intel.com Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Diffstat (limited to 'drivers/pci')
-rw-r--r--drivers/pci/pcie/dpc.c15
-rw-r--r--drivers/pci/quirks.c36
2 files changed, 46 insertions, 5 deletions
diff --git a/drivers/pci/pcie/dpc.c b/drivers/pci/pcie/dpc.c
index 3e9afee02e8d..f5ffea17c7f8 100644
--- a/drivers/pci/pcie/dpc.c
+++ b/drivers/pci/pcie/dpc.c
@@ -335,11 +335,16 @@ void pci_dpc_init(struct pci_dev *pdev)
return;
pdev->dpc_rp_extensions = true;
- pdev->dpc_rp_log_size = (cap & PCI_EXP_DPC_RP_PIO_LOG_SIZE) >> 8;
- if (pdev->dpc_rp_log_size < 4 || pdev->dpc_rp_log_size > 9) {
- pci_err(pdev, "RP PIO log size %u is invalid\n",
- pdev->dpc_rp_log_size);
- pdev->dpc_rp_log_size = 0;
+
+ /* Quirks may set dpc_rp_log_size if device or firmware is buggy */
+ if (!pdev->dpc_rp_log_size) {
+ pdev->dpc_rp_log_size =
+ (cap & PCI_EXP_DPC_RP_PIO_LOG_SIZE) >> 8;
+ if (pdev->dpc_rp_log_size < 4 || pdev->dpc_rp_log_size > 9) {
+ pci_err(pdev, "RP PIO log size %u is invalid\n",
+ pdev->dpc_rp_log_size);
+ pdev->dpc_rp_log_size = 0;
+ }
}
}
diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 4944798e75b5..285acc4aaccc 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -5956,3 +5956,39 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x56b1, aspm_l1_acceptable_latency
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x56c0, aspm_l1_acceptable_latency);
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x56c1, aspm_l1_acceptable_latency);
#endif
+
+#ifdef CONFIG_PCIE_DPC
+/*
+ * Intel Tiger Lake and Alder Lake BIOS has a bug that clears the DPC
+ * RP PIO Log Size of the integrated Thunderbolt PCIe Root Ports.
+ */
+static void dpc_log_size(struct pci_dev *dev)
+{
+ u16 dpc, val;
+
+ dpc = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_DPC);
+ if (!dpc)
+ return;
+
+ pci_read_config_word(dev, dpc + PCI_EXP_DPC_CAP, &val);
+ if (!(val & PCI_EXP_DPC_CAP_RP_EXT))
+ return;
+
+ if (!((val & PCI_EXP_DPC_RP_PIO_LOG_SIZE) >> 8)) {
+ pci_info(dev, "Overriding RP PIO Log Size to 4\n");
+ dev->dpc_rp_log_size = 4;
+ }
+}
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x461f, dpc_log_size);
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x462f, dpc_log_size);
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x463f, dpc_log_size);
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x466e, dpc_log_size);
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x9a23, dpc_log_size);
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x9a25, dpc_log_size);
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x9a27, dpc_log_size);
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x9a29, dpc_log_size);
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x9a2b, dpc_log_size);
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x9a2d, dpc_log_size);
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x9a2f, dpc_log_size);
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x9a31, dpc_log_size);
+#endif