We need the entire downstream bus range, not just the base bus number, to support _CBA. See the PCI Firmware spec, rev 3.0, sec 4.1.3. It's clear that the bus range is supposed to be in _CRS, but if we don't find it there, we'll assume [_BBN - 0xFF]. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@xxxxxx> --- drivers/acpi/pci_root.c | 19 +++++++++++++------ include/acpi/acpi_bus.h | 1 + 2 files changed, 14 insertions(+), 6 deletions(-) diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c index aa9eeee..a3e6f0e 100644 --- a/drivers/acpi/pci_root.c +++ b/drivers/acpi/pci_root.c @@ -485,16 +485,22 @@ static int __devinit acpi_pci_root_add(struct acpi_device *device) /* Check _CRS first, then _BBN. If no _BBN, default to zero. */ secondary.start = 0; + secondary.end = 0xFF; status = try_get_root_bridge_busnr(device->handle, &secondary); - if (ACPI_SUCCESS(status)) { - bus = secondary.start; - } else { + if (ACPI_FAILURE(status)) { + /* + * We need both the start and end of the downstream bus range + * to interpret _CBA (MMCONFIG base address), so it really is + * supposed to be in _CRS. + */ + printk(KERN_WARNING FW_BUG PREFIX + "no secondary bus range in _CRS\n"); status = acpi_evaluate_integer(device->handle, METHOD_NAME__BBN, NULL, &bus); if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) { - printk(KERN_ERR PREFIX - "no bus number in _CRS and can't evaluate _BBN\n"); + printk(KERN_ERR PREFIX "can't evaluate _BBN\n"); return -ENODEV; } + secondary.start = bus; } root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL); @@ -504,7 +510,8 @@ static int __devinit acpi_pci_root_add(struct acpi_device *device) INIT_LIST_HEAD(&root->node); root->device = device; root->segment = segment & 0xFFFF; - root->bus_nr = bus & 0xFF; + root->bus_nr = secondary.start & 0xFF; + root->subordinate_bus_nr = secondary.end & 0xFF; strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME); strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS); device->driver_data = root; diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h index 3cd9ccd..3d6e6e8 100644 --- a/include/acpi/acpi_bus.h +++ b/include/acpi/acpi_bus.h @@ -371,6 +371,7 @@ struct acpi_pci_root { struct pci_bus *bus; u16 segment; u8 bus_nr; + u8 subordinate_bus_nr; u32 osc_support_set; /* _OSC state of support bits */ u32 osc_control_set; /* _OSC state of control bits */ -- To unsubscribe from this list: send the line "unsubscribe linux-ia64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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