Re: [Qemu-devel] [PATCH V7 23/24] apci: fix PXB behaviour if used with unsupported BIOS

[Marcel Apfelbaum]

On 05/31/2015 09:12 PM, Michael S. Tsirkin wrote:
> On Mon, May 25, 2015 at 06:34:01PM +0300, Marcel Apfelbaum wrote:
> > PXB does not work with unsupported bioses, but should
> > not interfere with normal OS operation.
> > We don't ship them anymore, but it's reasonable
> > to keep the work-around until we update the bios in qemu.
>
> We already did, did we not?
Yes, we did, but Gerd preferred to keep this patch around.
Adding him to thread.

CC: Gerd Hoffmann <address@hidden>

Thanks,
Marcel

> > Fix this by not adding PXB mem/IO chunks to _CRS
> > if they weren't configured by BIOS.
> >
> > Signed-off-by: Marcel Apfelbaum <address@hidden>
> > ---
> >   hw/i386/acpi-build.c | 87 ++++++++++++++++++++++++++++++++++------------------
> >   1 file changed, 58 insertions(+), 29 deletions(-)
> >
> > diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> > index f7d2c80..895d64c 100644
> > --- a/hw/i386/acpi-build.c
> > +++ b/hw/i386/acpi-build.c
> > @@ -784,6 +784,14 @@ static Aml *build_crs(PCIHostState *host,
> >               range_base = r->addr;
> >               range_limit = r->addr + r->size - 1;
> >
> > +            /*
> > +             * Work-around for old bioses
> > +             * that do not support multiple root buses
> > +             */
> > +            if (!range_base || range_base > range_limit) {
> > +                continue;
> > +            }
> > +
> >               if (r->type & PCI_BASE_ADDRESS_SPACE_IO) {
> >                   aml_append(crs,
> >                       aml_word_io(aml_min_fixed, aml_max_fixed,
> > @@ -817,45 +825,66 @@ static Aml *build_crs(PCIHostState *host,
> >
> >               range_base = pci_bridge_get_base(dev, PCI_BASE_ADDRESS_SPACE_IO);
> >               range_limit = pci_bridge_get_limit(dev, 
> > PCI_BASE_ADDRESS_SPACE_IO);
> > -            aml_append(crs,
> > -                aml_word_io(aml_min_fixed, aml_max_fixed,
> > -                            aml_pos_decode, aml_entire_range,
> > -                            0,
> > -                            range_base,
> > -                            range_limit,
> > -                            0,
> > -                            range_limit - range_base + 1));
> > -            crs_range_insert(io_ranges, range_base, range_limit);
> > +
> > +            /*
> > +             * Work-around for old bioses
> > +             * that do not support multiple root buses
> > +             */
> > +            if (range_base || range_base > range_limit) {
> > +                aml_append(crs,
> > +                           aml_word_io(aml_min_fixed, aml_max_fixed,
> > +                                       aml_pos_decode, aml_entire_range,
> > +                                       0,
> > +                                       range_base,
> > +                                       range_limit,
> > +                                       0,
> > +                                       range_limit - range_base + 1));
> > +                crs_range_insert(io_ranges, range_base, range_limit);
> > +            }
> >
> >               range_base =
> >                   pci_bridge_get_base(dev, PCI_BASE_ADDRESS_SPACE_MEMORY);
> >               range_limit =
> >                   pci_bridge_get_limit(dev, PCI_BASE_ADDRESS_SPACE_MEMORY);
> > -            aml_append(crs,
> > -                aml_dword_memory(aml_pos_decode, aml_min_fixed,
> > -                                 aml_max_fixed, aml_non_cacheable,
> > -                                 aml_ReadWrite,
> > -                                 0,
> > -                                 range_base,
> > -                                 range_limit,
> > -                                 0,
> > -                                 range_limit - range_base + 1));
> > -            crs_range_insert(mem_ranges, range_base, range_limit);
> > +
> > +            /*
> > +             * Work-around for old bioses
> > +             * that do not support multiple root buses
> > +             */
> > +            if (range_base || range_base > range_limit) {
> > +                aml_append(crs,
> > +                           aml_dword_memory(aml_pos_decode, aml_min_fixed,
> > +                                            aml_max_fixed, aml_non_cacheable,
> > +                                            aml_ReadWrite,
> > +                                            0,
> > +                                            range_base,
> > +                                            range_limit,
> > +                                            0,
> > +                                            range_limit - range_base + 1));
> > +                crs_range_insert(mem_ranges, range_base, range_limit);
> > +          }
> >
> >               range_base =
> >                   pci_bridge_get_base(dev, PCI_BASE_ADDRESS_MEM_PREFETCH);
> >               range_limit =
> >                   pci_bridge_get_limit(dev, PCI_BASE_ADDRESS_MEM_PREFETCH);
> > -            aml_append(crs,
> > -                aml_dword_memory(aml_pos_decode, aml_min_fixed,
> > -                                 aml_max_fixed, aml_non_cacheable,
> > -                                 aml_ReadWrite,
> > -                                 0,
> > -                                 range_base,
> > -                                 range_limit,
> > -                                 0,
> > -                                 range_limit - range_base + 1));
> > -            crs_range_insert(mem_ranges, range_base, range_limit);
> > +
> > +            /*
> > +             * Work-around for old bioses
> > +             * that do not support multiple root buses
> > +             */
> > +            if (range_base || range_base > range_limit) {
> > +                aml_append(crs,
> > +                           aml_dword_memory(aml_pos_decode, aml_min_fixed,
> > +                                            aml_max_fixed, aml_non_cacheable,
> > +                                            aml_ReadWrite,
> > +                                            0,
> > +                                            range_base,
> > +                                            range_limit,
> > +                                            0,
> > +                                            range_limit - range_base + 1));
> > +                crs_range_insert(mem_ranges, range_base, range_limit);
> > +            }
> >           }
> >       }
> >
> > --
> > 2.1.0