Re: [RFC v2 1/2] hw/pci-host/gpex: Allow to generate preserve boot config DSM #5

[Eric Auger]

Hi CHenxiangn

On 12/29/21 8:13 AM, chenxiang (M) via wrote:
> Hi Eric,
>
>
> 在 2021/10/5 16:53, Eric Auger 写道:
>> Add a 'preserve_config' field in struct GPEXConfig and
>> if set generate the DSM #5 for preserving PCI boot configurations.
>> The DSM presence is needed to expose RMRs.
>>
>> At the moment the DSM generation is not yet enabled.
>>
>> Signed-off-by: Eric Auger <eric.auger@redhat.com>
>> ---
>>   include/hw/pci-host/gpex.h |  1 +
>>   hw/pci-host/gpex-acpi.c    | 12 ++++++++++++
>>   2 files changed, 13 insertions(+)
>>
>> diff --git a/include/hw/pci-host/gpex.h b/include/hw/pci-host/gpex.h
>> index fcf8b63820..3f8f8ec38d 100644
>> --- a/include/hw/pci-host/gpex.h
>> +++ b/include/hw/pci-host/gpex.h
>> @@ -64,6 +64,7 @@ struct GPEXConfig {
>>       MemMapEntry pio;
>>       int         irq;
>>       PCIBus      *bus;
>> +    bool        preserve_config;
>>   };
>>     int gpex_set_irq_num(GPEXHost *s, int index, int gsi);
>> diff --git a/hw/pci-host/gpex-acpi.c b/hw/pci-host/gpex-acpi.c
>> index e7e162a00a..7dab259379 100644
>> --- a/hw/pci-host/gpex-acpi.c
>> +++ b/hw/pci-host/gpex-acpi.c
>> @@ -164,6 +164,12 @@ void acpi_dsdt_add_gpex(Aml *scope, struct
>> GPEXConfig *cfg)
>>                   aml_append(dev, aml_name_decl("_PXM",
>> aml_int(numa_node)));
>>               }
>>   +            if (cfg->preserve_config) {
>> +                method = aml_method("_DSM", 5, AML_SERIALIZED);
>
> I notice there is a ACPI BIOS Error when booting virtual machine which
> seems be caused by this patch as I add this patchset in my branch to
> test the function of vsmmu.
> It seems that it requires only 4 parameter for method _DSM, but use 5
> parameters here.
> The error log is as following:

Thank you for the heads up. Yes the problem was reported by Igor too in
https://www.mail-archive.com/qemu-devel@nongnu.org/msg842972.html.

At the moment the RMRR ACPI situation has not progressed on spec side or
kernel if I have not missed anything but sure I will take this into
account in my next respin.

Thanks!

Eric
>
> [    2.355459] ACPI BIOS Error (bug): Failure creating named object
> [\_SB.PCI0._DSM], AE_ALREADY_EXISTS (20210930/dswload2-327)
> [    2.355467] ACPI Error: AE_ALREADY_EXISTS, During name
> lookup/catalog (20210930/psobject-221)
> [    2.355470] ACPI: Skipping parse of AML opcode: OpcodeName
> unavailable (0x0014)
> [    2.355657] ACPI: 1 ACPI AML tables successfully acquired and loaded
> [    2.356321] ACPI: Interpreter enabled
> [    2.356323] ACPI: Using GIC for interrupt routing
> [    2.356333] ACPI: MCFG table detected, 1 entries
> [    2.361359] ARMH0011:00: ttyAMA0 at MMIO 0x9000000 (irq = 16,
> base_baud = 0) is a SBSA
> [    2.619805] printk: console [ttyAMA0] enabled
> [    2.622114] ACPI: PCI Root Bridge [PCI0] (domain 0000 [bus 00-ff])
> [    2.622788] acpi PNP0A08:00: _OSC: OS supports [ExtendedConfig ASPM
> ClockPM Segments MSI HPX-Type3]
> [    2.623776] acpi PNP0A08:00: _OSC: platform does not support [LTR]
> [    2.624600] acpi PNP0A08:00: _OSC: OS now controls [PCIeHotplug PME
> AER PCIeCapability]
> [    2.625721] acpi PNP0A08:00: ECAM area [mem
> 0x4010000000-0x401fffffff] reserved by PNP0C02:00
> [    2.626645] acpi PNP0A08:00: ECAM at [mem
> 0x4010000000-0x401fffffff] for [bus 00-ff]
> [    2.627450] ACPI: Remapped I/O 0x000000003eff0000 to [io
> 0x0000-0xffff window]
> [    2.628229] ACPI BIOS Error (bug): \_SB.PCI0._DSM: Excess arguments
> - ASL declared 5, ACPI requires 4 (20210930/nsarguments-166)
> [    2.629576] PCI host bridge to bus 0000:00
> [    2.630008] pci_bus 0000:00: root bus resource [mem
> 0x10000000-0x3efeffff window]
> [    2.630747] pci_bus 0000:00: root bus resource [io  0x0000-0xffff
> window]
> [    2.631405] pci_bus 0000:00: root bus resource [mem
> 0x8000000000-0xffffffffff window]
> [    2.632177] pci_bus 0000:00: root bus resource [bus 00-ff]
> [    2.632731] ACPI BIOS Error (bug): \_SB.PCI0._DSM: Excess arguments
> - ASL declared 5, ACPI requires 4 (20210930/nsarguments-166)
>
>
>> +                aml_append(method, aml_return(aml_int(0)));
>> +                aml_append(dev, method);
>> +            }
>> +
>>               acpi_dsdt_add_pci_route_table(dev, cfg->irq);
>>                 /*
>> @@ -191,6 +197,12 @@ void acpi_dsdt_add_gpex(Aml *scope, struct
>> GPEXConfig *cfg)
>>       aml_append(dev, aml_name_decl("_STR", aml_unicode("PCIe 0
>> Device")));
>>       aml_append(dev, aml_name_decl("_CCA", aml_int(1)));
>>   +    if (cfg->preserve_config) {
>> +        method = aml_method("_DSM", 5, AML_SERIALIZED);
>> +        aml_append(method, aml_return(aml_int(0)));
>> +        aml_append(dev, method);
>> +    }
>> +
>>       acpi_dsdt_add_pci_route_table(dev, cfg->irq);
>>         method = aml_method("_CBA", 0, AML_NOTSERIALIZED);
>
>