From: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx> [ Upstream commit 03038d84ace72678a9944524508f218a00377dc0 ] Intel DG2 discrete graphics PCIe endpoints advertise L1 acceptable exit latency to be < 1us even though they can actually tolerate unlimited exit latencies just fine. Quirk the L1 acceptable exit latency for these endpoints to be unlimited so ASPM L1 can be enabled. [bhelgaas: use FIELD_GET/FIELD_PREP, wordsmith comment & commit log] Link: https://lore.kernel.org/r/20220405093810.76613-1-mika.westerberg@xxxxxxxxxxxxxxx Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx> Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> Reviewed-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/pci/quirks.c | 47 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+) diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index da829274fc66..41aeaa235132 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -12,6 +12,7 @@ * file, where their drivers can use them. */ +#include <linux/bitfield.h> #include <linux/types.h> #include <linux/kernel.h> #include <linux/export.h> @@ -5895,3 +5896,49 @@ DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x1533, rom_bar_overlap_defect); DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x1536, rom_bar_overlap_defect); DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x1537, rom_bar_overlap_defect); DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x1538, rom_bar_overlap_defect); + +#ifdef CONFIG_PCIEASPM +/* + * Several Intel DG2 graphics devices advertise that they can only tolerate + * 1us latency when transitioning from L1 to L0, which may prevent ASPM L1 + * from being enabled. But in fact these devices can tolerate unlimited + * latency. Override their Device Capabilities value to allow ASPM L1 to + * be enabled. + */ +static void aspm_l1_acceptable_latency(struct pci_dev *dev) +{ + u32 l1_lat = FIELD_GET(PCI_EXP_DEVCAP_L1, dev->devcap); + + if (l1_lat < 7) { + dev->devcap |= FIELD_PREP(PCI_EXP_DEVCAP_L1, 7); + pci_info(dev, "ASPM: overriding L1 acceptable latency from %#x to 0x7\n", + l1_lat); + } +} +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x4f80, aspm_l1_acceptable_latency); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x4f81, aspm_l1_acceptable_latency); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x4f82, aspm_l1_acceptable_latency); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x4f83, aspm_l1_acceptable_latency); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x4f84, aspm_l1_acceptable_latency); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x4f85, aspm_l1_acceptable_latency); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x4f86, aspm_l1_acceptable_latency); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x4f87, aspm_l1_acceptable_latency); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x4f88, aspm_l1_acceptable_latency); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x5690, aspm_l1_acceptable_latency); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x5691, aspm_l1_acceptable_latency); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x5692, aspm_l1_acceptable_latency); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x5693, aspm_l1_acceptable_latency); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x5694, aspm_l1_acceptable_latency); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x5695, aspm_l1_acceptable_latency); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x56a0, aspm_l1_acceptable_latency); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x56a1, aspm_l1_acceptable_latency); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x56a2, aspm_l1_acceptable_latency); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x56a3, aspm_l1_acceptable_latency); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x56a4, aspm_l1_acceptable_latency); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x56a5, aspm_l1_acceptable_latency); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x56a6, aspm_l1_acceptable_latency); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x56b0, aspm_l1_acceptable_latency); +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 -- 2.35.1
