From 53762ba810398c11efaf65f9a45d992125e86dcf Mon Sep 17 00:00:00 2001 From: Zhou Wang Date: Wed, 4 Jan 2017 15:00:06 +0800 Subject: PCI/ACPI: Fix bus range comparison in pci_mcfg_lookup() The configuration data provided by an MCFG entry, i.e., PCI segment and bus range, may span multiple host bridges. pci_mcfg_lookup() previously required an exact match of the host bridge starting bus and the MCFG starting bus, which made the following configuration fail: MCFG region: segment: 0 bus range: 0x00-0xff host bridge segment: 0 bus range: 0x20-0x4f Relax the bus range check in pci_mcfg_lookup() so we can use any MCFG entry that contains the required bus range, as we do in pci_mmconfig_lookup(). [bhelgaas: changelog] Signed-off-by: Zhou Wang Signed-off-by: Bjorn Helgaas Reviewed-by: Tomasz Nowicki Acked-by: Lorenzo Pieralisi --- drivers/acpi/pci_mcfg.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/acpi/pci_mcfg.c b/drivers/acpi/pci_mcfg.c index a6a4ceaa6cc3..2944353253ed 100644 --- a/drivers/acpi/pci_mcfg.c +++ b/drivers/acpi/pci_mcfg.c @@ -195,11 +195,10 @@ int pci_mcfg_lookup(struct acpi_pci_root *root, struct resource *cfgres, goto skip_lookup; /* - * We expect exact match, unless MCFG entry end bus covers more than - * specified by caller. + * We expect the range in bus_res in the coverage of MCFG bus range. */ list_for_each_entry(e, &pci_mcfg_list, list) { - if (e->segment == seg && e->bus_start == bus_res->start && + if (e->segment == seg && e->bus_start <= bus_res->start && e->bus_end >= bus_res->end) { root->mcfg_addr = e->addr; } -- cgit v1.2.3