Re: [edk2-devel] [PATCH 1/1] OvmfPkg/PlatformInitLib: pass through reservations from qemu

["Ard Biesheuvel" <ardb@kernel.org>]

On Wed, 7 Dec 2022 at 06:32, Gerd Hoffmann <kraxel@redhat.com> wrote:
>
> qemu uses the etc/e820 fw_cfg file not only for memory, but
> also for reservations.  Handle reservations by adding resource
> descriptor hobs for them.
>
> A typical qemu configuration has a small reservation between
> lapic and flash:
>
>   # sudo cat /proc/iomem
>   [ ... ]
>   fee00000-fee00fff : Local APIC
>   feffc000-feffffff : Reserved          <= HERE
>   ffc00000-ffffffff : Reserved
>   [ ... ]
>
> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

Merged as #3828


> ---
>  OvmfPkg/Library/PlatformInitLib/MemDetect.c | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
>
> diff --git a/OvmfPkg/Library/PlatformInitLib/MemDetect.c b/OvmfPkg/Library/PlatformInitLib/MemDetect.c
> index b8feae4309de..a7a4e028ad50 100644
> --- a/OvmfPkg/Library/PlatformInitLib/MemDetect.c
> +++ b/OvmfPkg/Library/PlatformInitLib/MemDetect.c
> @@ -228,6 +228,22 @@ PlatformScanOrAdd64BitE820Ram (
>              ));
>          }
>        }
> +    } else if (E820Entry.Type == EfiAcpiAddressRangeReserved) {
> +      if (AddHighHob) {
> +        DEBUG ((
> +          DEBUG_INFO,
> +          "%a: Reserved: Base=0x%Lx Length=0x%Lx\n",
> +          __FUNCTION__,
> +          E820Entry.BaseAddr,
> +          E820Entry.Length
> +          ));
> +        BuildResourceDescriptorHob (
> +          EFI_RESOURCE_MEMORY_RESERVED,
> +          0,
> +          E820Entry.BaseAddr,
> +          E820Entry.Length
> +          );
> +      }
>      }
>    }
>
> --
> 2.38.1
>
>
>
> 
>
>