UefiCpuPkg/CpuS3DataDxe: Remove below 4G limitation.

Because PrepareApStartupVector() stores StackAddress to
"mExchangeInfo->StackStart" (which has type (VOID*)), and because
"UefiCpuPkg/PiSmmCpuDxeSmm/X64/MpFuncs.nasm" reads the latter with:

         add  edi, StackStartAddressLocation
         add  rax, qword [edi]
         mov  rsp, rax
         mov  qword [edi], rax

in long-mode code. So code can remove below 4G limitation.

Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
Tested-by: Laszlo Ersek <lersek@redhat.com>

1 files changed, 9 insertions, 8 deletions

diff --git a/UefiCpuPkg/CpuS3DataDxe/CpuS3Data.c b/UefiCpuPkg/CpuS3DataDxe/CpuS3Data.c
index 3e8c8b383c..ef98239844 100644
--- a/UefiCpuPkg/CpuS3DataDxe/CpuS3Data.c
+++ b/UefiCpuPkg/CpuS3DataDxe/CpuS3Data.c
@@ -47,9 +47,7 @@ typedef struct {
 } ACPI_CPU_DATA_EX;

 

 /**

-  Allocate EfiACPIMemoryNVS below 4G memory address.

-

-  This function allocates EfiACPIMemoryNVS below 4G memory address.

+  Allocate EfiACPIMemoryNVS memory.

 

   @param[in] Size   Size of memory to allocate.

 

@@ -57,7 +55,7 @@ typedef struct {
 

 **/

 VOID *

-AllocateAcpiNvsMemoryBelow4G (

+AllocateAcpiNvsMemory (

   IN UINTN  Size

   )

 {

@@ -65,9 +63,8 @@ AllocateAcpiNvsMemoryBelow4G (
   EFI_STATUS            Status;

   VOID                  *Buffer;

 

-  Address = BASE_4GB - 1;

   Status  = gBS->AllocatePages (

-                   AllocateMaxAddress,

+                   AllocateAnyPages,

                    EfiACPIMemoryNVS,

                    EFI_SIZE_TO_PAGES (Size),

                    &Address

@@ -230,9 +227,13 @@ CpuS3DataInitialize (
   AcpiCpuData->MtrrTable    = (EFI_PHYSICAL_ADDRESS)(UINTN)&AcpiCpuDataEx->MtrrTable;

 

   //

-  // Allocate stack space for all CPUs

+  // Allocate stack space for all CPUs.

+  // Use ACPI NVS memory type because this data will be directly used by APs

+  // in S3 resume phase in long mode. Also during S3 resume, the stack buffer

+  // will only be used as scratch space. i.e. we won't read anything from it

+  // before we write to it, in PiSmmCpuDxeSmm.

   //

-  Stack = AllocateAcpiNvsMemoryBelow4G (NumberOfCpus * AcpiCpuData->StackSize);

+  Stack = AllocateAcpiNvsMemory (NumberOfCpus * AcpiCpuData->StackSize);

   ASSERT (Stack != NULL);

   AcpiCpuData->StackAddress = (EFI_PHYSICAL_ADDRESS)(UINTN)Stack;