On Tue, Jun 15, 2021 at 1:33 PM Hans de Goede <hdegoede@xxxxxxxxxx> wrote: > > Hi, > > On 6/15/21 12:59 PM, Rafael J. Wysocki wrote: > > On Tue, Jun 15, 2021 at 12:26 PM Hans de Goede <hdegoede@xxxxxxxxxx> wrote: > >> > >> 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. > > > > Also, a memory resource starting at 0 is not usable in Linux anyway > > AFAICS, at least on x86. > > Right, but I was wondering about other arches. Maybe wrap the new check in > "#if IS_ENABLED(CONFIG_X86)" ? That would be prudent, because all of the known affected machines are x86. > >> --- > >> 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); > > > > Makes sense to me (small nit: I wouldn't break the like above). > > > >> + free = true; > >> + goto next; > >> + } > >> + > >> /* Exclude non-addressable range or non-addressable portion */ > >> end = min(res1->end, root->end); > >> if (end <= res1->start) { > >> -- > > >