On some Lenovo laptops the base-addrsss of some PCI devices is left at 0 at boot: [ 0.283145] pci 0000:00:15.0: [8086:34e8] type 00 class 0x0c8000 [ 0.283217] pci 0000:00:15.0: reg 0x10: [mem 0x00000000-0x00000fff 64bit] [ 0.285117] pci 0000:00:15.1: [8086:34e9] type 00 class 0x0c8000 [ 0.285189] pci 0000:00:15.1: reg 0x10: [mem 0x00000000-0x00000fff 64bit] There is a _CRS method for these devices, which simply returns the configured 0 address. This is causing the PCI core to not assign memory to these PCI devices and is causing these errors: [ 0.655335] pci 0000:00:15.0: BAR 0: no space for [mem size 0x00001000 64bit] [ 0.655337] pci 0000:00:15.0: BAR 0: failed to assign [mem size 0x00001000 64bit] [ 0.655339] pci 0000:00:15.1: BAR 0: no space for [mem size 0x00001000 64bit] [ 0.655340] pci 0000:00:15.1: BAR 0: failed to assign [mem size 0x00001000 64bit] This happens specifically for the designware I2C PCI devices on these laptops, causing I2C-HID attached touchpads/touchscreens to not work. Booting with nocrs on these devices results in the kernel itself assigning memory to these devices, fixing things: [ 0.355716] pci 0000:00:15.0: BAR 0: assigned [mem 0x29c000000-0x29c000fff 64bit] [ 0.355783] pci 0000:00:15.1: BAR 0: assigned [mem 0x29c001000-0x29c001fff 64bit] At least the following models are known to be affected by this (but there might be more): Lenovo IdeaPad 3 15IIL05 81WE Lenovo IdeaPad 5 14IIL05 81YH Add an extra check for the base-address being 0 to acpi_pci_root_validate_resources() and reject IOMEM resources where this is the case, to fix this issue. BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1871793 BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1868899 BugLink: https://bugs.launchpad.net/ubuntu/+source/linux-signed-hwe/+bug/1878279 Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx> --- Note we could instead add the known to be affected models to the pci_crs_quirks table in arch/x86/pci/acpi.c, but it is likely that more systems are affected and a more generic fix seems better in general. --- drivers/acpi/pci_root.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c index dcd593766a64..6cd2ca551005 100644 --- a/drivers/acpi/pci_root.c +++ b/drivers/acpi/pci_root.c @@ -686,6 +686,13 @@ static void acpi_pci_root_validate_resources(struct device *dev, if (!(res1->flags & type)) goto next; + if ((type & IORESOURCE_MEM) && res1->start == 0) { + dev_info(dev, "host bridge window %pR (ignored, start address not set)\n", + res1); + free = true; + goto next; + } + /* Exclude non-addressable range or non-addressable portion */ end = min(res1->end, root->end); if (end <= res1->start) { -- 2.31.1