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

[Marcel Apfelbaum <marcel@redhat.com>]

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 <marcel@redhat.com>
>> ---
>>   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();
>> --
>> 2.1.0