@@ -1687,3 +1687,51 @@ EfiLocateProtocolBuffer (
return EFI_SUCCESS;
}
+
+/**
+ Allocates one or more 4KB pages of a given type from a memory region that is
+ accessible to PEI.
+
+ Allocates the number of 4KB pages of type 'MemoryType' and returns a
+ pointer to the allocated buffer. The buffer returned is aligned on a 4KB
+ boundary. If Pages is 0, then NULL is returned. If there is not enough
+ memory remaining to satisfy the request, then NULL is returned.
+
+ @param[in] MemoryType The memory type to allocate
+ @param[in] Pages The number of 4 KB pages to allocate.
+
+ @return A pointer to the allocated buffer or NULL if allocation fails.
+
+**/
+VOID *
+EFIAPI
+EfiAllocatePeiAccessiblePages (
+ IN EFI_MEMORY_TYPE MemoryType,
+ IN UINTN Pages
+ )
+{
+ EFI_STATUS Status;
+ EFI_PHYSICAL_ADDRESS Memory;
+ EFI_ALLOCATE_TYPE AllocType;
+
+ if (Pages == 0) {
+ return NULL;
+ }
+
+#ifdef MDE_CPU_X64
+ //
+ // On X64 systems, a X64 build of DXE may be combined with a 32-bit build of
+ // PEI, and so we need to allocate below 4 GB to ensure that the allocation
+ // is accessible by PEI.
+ //
+ AllocType = AllocateMaxAddress;
+ Memory = MAX_UINT32;
+#else
+ AllocType = AllocateAnyPages;
+#endif
+ Status = gBS->AllocatePages (AllocType, MemoryType, Pages, &Memory);
+ if (EFI_ERROR (Status)) {
+ return NULL;
+ }
+ return (VOID *)(UINTN)Memory;
+}
Add the newly introduced EfiAllocatePeiAccessiblePages() routine which allocates memory in a way that guarantees that PEI can access it after a warm reboot. Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> --- IntelFrameworkPkg/Library/FrameworkUefiLib/UefiLib.c | 48 ++++++++++++++++++++ 1 file changed, 48 insertions(+) -- 2.17.0 _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel