Re: [Qemu-devel] [PATCH 07/17] e500: fix pci host bridge class/type

[David Gibson]

On Sun, Nov 26, 2017 at 03:59:05PM -0600, Michael Davidsaver wrote:
> Correct some confusion wrt. the PCI facing
> side of the PCI host bridge (not PCIe root complex).
> The ref. manual for the mpc8533 (as well as
> mpc8540 and mpc8540) give the class code as
> PCI_CLASS_PROCESSOR_POWERPC.
> While the PCI_HEADER_TYPE field is oddly omitted,
> the tables in the "PCI Configuration Header"
> section shows a type 0 layout using all 6 BAR
> registers (as 2x 32, and 2x 64 bit regions)
> 
> So 997505065dc92e533debf5cb23012ba4e673d387
> seems to be in error.  Although there was
> perhaps some confusion as the mpc8533
> has a separate PCIe root complex.
> With PCIe, a root complex has PCI_HEADER_TYPE=1.
> 
> Neither the PCI host bridge, nor the PCIe
> root complex advertise class PCI_CLASS_BRIDGE_PCI.
> 
> This was confusing Linux guests, which try
> to interpret the host bridge as a pci-pci
> bridge, but get confused and re-enumerate
> the bus when the primary/secondary/subordinate
> bus registers don't have valid values.
> 
> Signed-off-by: Michael Davidsaver <address@hidden>

Applied to ppc-for-2.12.

> ---
>  hw/pci-host/ppce500.c | 5 -----
>  1 file changed, 5 deletions(-)
> 
> diff --git a/hw/pci-host/ppce500.c b/hw/pci-host/ppce500.c
> index f2d108bc8a..8073d396ff 100644
> --- a/hw/pci-host/ppce500.c
> +++ b/hw/pci-host/ppce500.c
> @@ -423,11 +423,6 @@ static void e500_pcihost_bridge_realize(PCIDevice *d, 
> Error **errp)
>                                                        "/e500-ccsr"));
>      MemoryRegion *ccsr_mr = sysbus_mmio_get_region(ccsr, 0);
>  
> -    pci_config_set_class(d->config, PCI_CLASS_BRIDGE_PCI);
> -    d->config[PCI_HEADER_TYPE] =
> -        (d->config[PCI_HEADER_TYPE] & PCI_HEADER_TYPE_MULTI_FUNCTION) |
> -        PCI_HEADER_TYPE_BRIDGE;
> -
>      memory_region_init_alias(&b->bar0, OBJECT(ccsr), "e500-pci-bar0", 
> ccsr_mr,
>                               0, memory_region_size(ccsr_mr));
>      pci_register_bar(d, 0, PCI_BASE_ADDRESS_SPACE_MEMORY, &b->bar0);

-- 
David Gibson                    | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au  | minimalist, thank you.  NOT _the_ _other_
                                | _way_ _around_!
http://www.ozlabs.org/~dgibson

signature.asc
Description: PGP signature