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

[chenxiang (M)]

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:

[    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);