On 2017/1/4 15:00, Zhou Wang wrote: > The configuration data provided by an MCFG region (ie PCI segment and > bus range) may span multiple host bridges. > > Current code in pci_mcfg_lookup() carries out an exact match of host > bridge bus range start value against the MCFG region(s) bus range start > value which would cause configurations like the following: > > MCFG region: > bus range: 0x00~0xff. > segment: 0. > > PCI host bridges configuration (segment numbers and bus ranges): > host bridge 1: > bus range: 0x00~0x1f. > segment: 0. > host bridge 2: > bus range: 0x20~0x4f. > segment: 0. > > to fail, in that the bus range start value for host bridge 2 does > not match the bus range start value of the respective MCFG region. > > Relax the bus range check in pci_mcfg_lookup() to cater for > PCI configurations with multiple host bridges sharing the same > MCFG region. > > Signed-off-by: Zhou Wang <[email protected]> > Reviewed-by: Tomasz Nowicki <[email protected]> > Acked-by: Lorenzo Pieralisi <[email protected]> > --- > 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 a6a4cea..2944353 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; > } >
Hi Rafael, Could you please look into this patch if you have time? Thanks, Zhou
