5.15-stable review patch. If anyone has any objections, please let me know.
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From: Mika Westerberg mika.westerberg@linux.intel.com
[ Upstream commit 5459c0b7046752e519a646e1c2404852bb628459 ]
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... 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 Stable-dep-of: 627c6db20703 ("PCI/DPC: Quirk PIO log size for Intel Raptor Lake Root Ports") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/pci/pcie/dpc.c | 15 ++++++++++----- drivers/pci/quirks.c | 36 ++++++++++++++++++++++++++++++++++++ 2 files changed, 46 insertions(+), 5 deletions(-)
diff --git a/drivers/pci/pcie/dpc.c b/drivers/pci/pcie/dpc.c index cf0d4ba2e157a..ab83f78f3eb1d 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 3217d4aaea598..59b3dd33092bf 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -5950,3 +5950,39 @@ 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