Re: [Qemu-devel] [RFC PATCH 2/2] pci: enable RedHat pci bridges to reserve more buses

[Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>]

On Wed, Jul 19, 2017 at 04:20:14PM +0300, Aleksandr Bezzubikov wrote:
> In case of RedHat PCI bridges reserve additional buses, which number is provided

It is "Red Hat"
> in a vendor-specific capability.

And perhaps also a #define ?
> 
> Signed-off-by: Aleksandr Bezzubikov <zuban32s@gmail.com>
> ---
>  src/fw/pciinit.c | 12 ++++++++++--
>  1 file changed, 10 insertions(+), 2 deletions(-)
> 
> diff --git a/src/fw/pciinit.c b/src/fw/pciinit.c
> index 08221e6..b6f3a01 100644
> --- a/src/fw/pciinit.c
> +++ b/src/fw/pciinit.c
> @@ -578,9 +578,17 @@ pci_bios_init_bus_rec(int bus, u8 *pci_bus)
>          pci_bios_init_bus_rec(secbus, pci_bus);
>  
>          if (subbus != *pci_bus) {
> +            u16 vendor = pci_config_readw(bdf, PCI_VENDOR_ID);
> +            u8 res_bus = 0;
> +            if (vendor == 0x1b36) {
> +                u8 cap = pci_find_capability_bdf(bdf, PCI_CAP_ID_VNDR, 0);
> +                if (cap) {
> +                    res_bus = pci_config_readb(bdf, cap + 16);
> +                }
> +            }
>              dprintf(1, "PCI: subordinate bus = 0x%x -> 0x%x\n",
> -                    subbus, *pci_bus);
> -            subbus = *pci_bus;
> +                    subbus, *pci_bus + res_bus);
> +            subbus = *pci_bus + res_bus;
>          } else {
>              dprintf(1, "PCI: subordinate bus = 0x%x\n", subbus);
>          }
> -- 
> 2.7.4
> 
>