On Tue, Jun 15, 2021 at 12:25:55PM +0200, Hans de Goede 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] s/base-addrsss/base-address/ Timestamps aren't relevant here and can be trimmed. It's not really an error if BIOS leaves a PCI BAR unprogrammed. > 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] I'm confused. Did you say there's a _CRS method for these *PCI* devices (0000:00:15.0, 0000:00:15.1)? I suspect you mean the *host bridge* has a _CRS method, since I think acpi_pci_root_validate_resources() is looking at contents of the host bridge _CRS. On x86, it would likely be a BIOS defect is a host bridge _CRS had a memory window starting at 0, but you didn't show what _CRS contained. The dmesg at https://bugzilla.redhat.com/show_bug.cgi?id=1871793 shows this, which looks totally normal and should be unaffected by the patch since there's no memory window starting at 0: pci_bus 0000:00: root bus resource [io 0x0000-0x0cf7 window] pci_bus 0000:00: root bus resource [io 0x0d00-0xffff window] pci_bus 0000:00: root bus resource [mem 0x000a0000-0x000bffff window] pci_bus 0000:00: root bus resource [mem 0x6d400000-0xbfffffff window] The ones at https://bugzilla.redhat.com/show_bug.cgi?id=1868899 and https://bugs.launchpad.net/ubuntu/+source/linux-signed-hwe/+bug/1878279 are similar, so I can't quite connect the dots here. > 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: "pci=nocrs" to help people repro this or try the same workaround elsewhere. > [ 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. Definitely good to avoid pci_crs_quirks[] because throwing away _CRS completely leads us into uncharted waters, especially for multi-host bridge systems that support hotplug. > --- > 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 >
