X-Git-Url: https://git.proxmox.com/?a=blobdiff_plain;f=IntelFrameworkModulePkg%2FCsm%2FLegacyBiosDxe%2FLegacyBootSupport.c;fp=IntelFrameworkModulePkg%2FCsm%2FLegacyBiosDxe%2FLegacyBootSupport.c;h=5575d2ec8eb9f8907eded90a2df1b4ff1cacc792;hb=800765aa19a8059a001652d3d190e594ed651694;hp=6c2688b4a423cf7e5e0db2fd1d5c375f9d342a77;hpb=718abab1121bfae91b9d4daa1d9fa17879d9ed32;p=mirror_edk2.git

diff --git a/IntelFrameworkModulePkg/Csm/LegacyBiosDxe/LegacyBootSupport.c b/IntelFrameworkModulePkg/Csm/LegacyBiosDxe/LegacyBootSupport.c
index 6c2688b4a4..5575d2ec8e 100644
--- a/IntelFrameworkModulePkg/Csm/LegacyBiosDxe/LegacyBootSupport.c
+++ b/IntelFrameworkModulePkg/Csm/LegacyBiosDxe/LegacyBootSupport.c
@@ -1613,6 +1613,12 @@ EfiMemoryTypeToE820Type (
   case EfiBootServicesCode:
   case EfiBootServicesData:
   case EfiConventionalMemory:
+  //
+  // The memory of EfiRuntimeServicesCode and EfiRuntimeServicesData are
+  // usable memory for legacy OS.
+  // In ACPI specification, EfiRuntimeServiceCode and EfiRuntimeServiceData
+  // should be mapped to AddressRangeReserved. This statement is for UEFI OS, not for legacy OS.
+  //
   case EfiRuntimeServicesCode:
   case EfiRuntimeServicesData:
     return EfiAcpiAddressRangeMemory;