Re: [Qemu-devel] [PATCH v4 4/5] acpi: arm: add fw_cfg device node to dsdt

[Laszlo Ersek <lersek@redhat.com>]

On 09/27/15 23:29, Gabriel L. Somlo wrote:
> Add a fw_cfg device node to the ACPI DSDT. This is mostly
> informational, as the authoritative fw_cfg MMIO region(s)
> are listed in the Device Tree. However, since we are building
> ACPI tables, we might as well be thorough while at it...
> 
> Signed-off-by: Gabriel Somlo <somlo@cmu.edu>
> ---
>  hw/arm/virt-acpi-build.c | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
> 
> diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
> index 1aaff1f..f314132 100644
> --- a/hw/arm/virt-acpi-build.c
> +++ b/hw/arm/virt-acpi-build.c
> @@ -110,6 +110,20 @@ static void acpi_dsdt_add_rtc(Aml *scope, const MemMapEntry *rtc_memmap,
>      aml_append(scope, dev);
>  }
>  
> +static void acpi_dsdt_add_fw_cfg(Aml *scope, const MemMapEntry *fw_cfg_memmap)
> +{
> +    Aml *dev = aml_device("FWCF");
> +    aml_append(dev, aml_name_decl("_HID", aml_string("QEMU0002")));
> +    /* device present, functioning, decoding, not shown in UI */
> +    aml_append(dev, aml_name_decl("_STA", aml_int(0xB)));
> +
> +    Aml *crs = aml_resource_template();
> +    aml_append(crs, aml_memory32_fixed(fw_cfg_memmap->base,
> +                                       fw_cfg_memmap->size, AML_READ_WRITE));
> +    aml_append(dev, aml_name_decl("_CRS", crs));
> +    aml_append(scope, dev);
> +}
> +
>  static void acpi_dsdt_add_flash(Aml *scope, const MemMapEntry *flash_memmap)
>  {
>      Aml *dev, *crs;
> @@ -529,6 +543,7 @@ build_dsdt(GArray *table_data, GArray *linker, VirtGuestInfo *guest_info)
>                         (irqmap[VIRT_UART] + ARM_SPI_BASE));
>      acpi_dsdt_add_rtc(scope, &memmap[VIRT_RTC],
>                        (irqmap[VIRT_RTC] + ARM_SPI_BASE));
> +    acpi_dsdt_add_fw_cfg(scope, &memmap[VIRT_FW_CFG]);
>      acpi_dsdt_add_flash(scope, &memmap[VIRT_FLASH]);
>      acpi_dsdt_add_virtio(scope, &memmap[VIRT_MMIO],
>                      (irqmap[VIRT_MMIO] + ARM_SPI_BASE), NUM_VIRTIO_TRANSPORTS);
> 

Looks sane to me.

Did you test this with an aarch64 Linux guest (acpidump -b; iasl -d; cat
/proc/iomem?) I can help with that, if you'd like.

Reviewed-by: Laszlo Ersek <lersek@redhat.com>

Thanks
Laszlo