| Message ID | 20150616165550.9306.58789.stgit@bhelgaas-glaptop2.roam.corp.google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
diff --git a/arch/x86/pci/acpi.c b/arch/x86/pci/acpi.c index d8e2258..2ae7ce2 100644 --- a/arch/x86/pci/acpi.c +++ b/arch/x86/pci/acpi.c @@ -132,8 +132,10 @@ void __init pci_acpi_crs_quirks(void) { int year; - if (dmi_get_date(DMI_BIOS_DATE, &year, NULL, NULL) && year < 2008) - pci_use_crs = false; + if (dmi_get_date(DMI_BIOS_DATE, &year, NULL, NULL) && year < 2008) { + if (iomem_resource.end <= 0xffffffff) + pci_use_crs = false; + } dmi_check_system(pci_crs_quirks);
We enable _CRS on all systems from 2008 and later. On older systems, we ignore _CRS and assume the whole physical address space (excluding RAM and other devices) is available for PCI devices, but on systems that support physical address spaces larger than 4GB, it's doubtful that the area above 4GB is really available for PCI. After d56dbf5bab8c ("PCI: Allocate 64-bit BARs above 4G when possible"), we try to use that space above 4GB *first*, so we're more likely to put a device there. Several people have reported sound problems related to putting a device above 4GB. This could happen with any device; I assume it's more likely for sound devices because the BIOS is more likely to leave them unassigned. Keep _CRS enabled even on pre-2008 systems if they support physical address space larger than 4GB. Fixes: d56dbf5bab8c ("PCI: Allocate 64-bit BARs above 4G when possible") Reported-by: dayer <dayer3@gmail.com> Link: https://bugzilla.kernel.org/show_bug.cgi?id=99221 Link: https://bugzilla.opensuse.org/show_bug.cgi?id=907092 Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> --- arch/x86/pci/acpi.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html