Re: [SeaBIOS] [Qemu-devel] [PATCH v4 for-2.3 10/25] hw/acpi: add support for multiple root busses

[Marcel Apfelbaum]

On 03/08/2015 06:10 PM, Michael S. Tsirkin wrote:
> On Sun, Mar 08, 2015 at 01:16:12PM +0200, Marcel Apfelbaum wrote:
> > If the machine has several root busses, we need to add them to
> > acpi in order to be properly detected by guests.
> > Signed-off-by: Marcel Apfelbaum
> >
> > hw/i386/acpi-build.c | 32 ++++++++++++++++++++++++++++++++
> >   1 file changed, 32 insertions(+)
> >
> > diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> > index b94e47e..e5709e8 100644
> > --- a/hw/i386/acpi-build.c
> > +++ b/hw/i386/acpi-build.c
> > @@ -60,6 +60,8 @@
> >   #include "qom/qom-qobject.h"
> >   #include "exec/ram_addr.h"
> >
> > +#include "qmp-commands.h"
> > /* These are used to size the ACPI tables for -M pc-i440fx-1.7 and
> > -M pc-i440fx-2.0.  Even if the actual amount of AML generated grows
> > a little bit, there should be plenty of free space since the DSDT
> >
> > @@ -682,6 +684,36 @@ build_ssdt(GArray *table_data, GArray *linker,
> >       /* Reserve space for header */
> >       acpi_data_push(ssdt->buf, sizeof(AcpiTableHeader));
> > {
> >    PciInfoList *info_list, *info;
> >    Error *err = NULL;
> >    info_list = qmp_query_pci(&err);
> >    if (err) {
> >        error_free(err);
> >        return;
> >    }
> >    for (info = info_list; info; info = info->next) {
> >        PciInfo *bus_info = info->value;

Hi,
> >        if (bus_info->bus == 0) {
> >            continue;
> >        }

[1] This code works only for root buses with bus number > 0
> >        scope = aml_scope("\\_SB");
> >        dev = aml_device("PC%.02X", (uint8_t)bus_info->bus);
> >        aml_append(dev, aml_name_decl("_UID",
> >            aml_string("PC%.02X", (uint8_t)bus_info->bus)));
> >        aml_append(dev, aml_name_decl("_HID", aml_string("PNP0A03")));
> >        aml_append(dev,
> >            aml_name_decl("_BBN", aml_int((uint8_t)bus_info->bus)));
>
> Hmm not all pci buses have hardware-assigned bus numbers,
> a separate segment is also an option.
> How about only getting your specific ones?

As you can see it [1] we only deal with buses that have
hardware-assigned bus numbers, and if the bus number is > 0,
we *must* supply BBN. So at the end, it works only for our PXBs.

Thanks,
Marcel
> >        aml_append(scope, dev);
> >        aml_append(ssdt, scope);
> >    }
> >    qapi_free_PciInfoList(info_list);
> > }
> > scope = aml_scope("\\_SB.PCI0");
> > /* build PCI0._CRS */
> > crs = aml_resource_template();