During the finalization of Mp initialization before booting into the OS,
depending on whether Mwait is supported or not, AsmRelocateApLoop
places Aps in MWAIT-loop or HLT-loop.
Since paging is necessary for long mode, the original implementation of
moving APs to 32-bit was to disable paging to ensure that the booting
does not crash.
The current modification creates a page table in reserved memory,
avoiding switching modes and reclaiming memory by OS.
More specifically, we keep the AMD logic as the original code flow,
extract and update the Intel-related code, where the APs would stay
in 64-bit, and run in a Mwait or Hlt loop until the OS wake them up.
Signed-off-by: Ray Ni <ray...@intel.com>
Signed-off-by: Yuanhao Xie <yuanhao....@intel.com>
---
UefiCpuPkg/Library/MpInitLib/DxeMpInitLib.inf | 1 +
UefiCpuPkg/Library/MpInitLib/DxeMpLib.c | 127
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++---------------------------------------------------
UefiCpuPkg/Library/MpInitLib/MpLib.h | 5 +----
UefiCpuPkg/Library/MpInitLib/X64/MpFuncs.nasm | 171
+++++++++++++++++++++++++++------------------------------------------------------------------------------------------------------------------------------------------------
4 files changed, 105 insertions(+), 199 deletions(-)
diff --git a/UefiCpuPkg/Library/MpInitLib/DxeMpInitLib.inf
b/UefiCpuPkg/Library/MpInitLib/DxeMpInitLib.inf
index cd07de3a3c..f19c6c9958 100644
--- a/UefiCpuPkg/Library/MpInitLib/DxeMpInitLib.inf
+++ b/UefiCpuPkg/Library/MpInitLib/DxeMpInitLib.inf
@@ -56,6 +56,7 @@
PcdLib
CcExitLib
MicrocodeLib
+ CpuPageTableLib
[Protocols]
gEfiTimerArchProtocolGuid ## SOMETIMES_CONSUMES
diff --git a/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c
b/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c
index 31caa9211f..517220331a 100644
--- a/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c
+++ b/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c
@@ -13,9 +13,11 @@
#include <Library/DebugAgentLib.h>
#include <Library/DxeServicesTableLib.h>
#include <Library/CcExitLib.h>
+#include <Library/CpuPageTableLib.h>
#include <Register/Amd/Fam17Msr.h>
#include <Register/Amd/Ghcb.h>
+#include <Guid/EventGroup.h>
#include <Protocol/Timer.h>
#define AP_SAFE_STACK_SIZE 128
@@ -28,6 +30,7 @@ volatile BOOLEAN mStopCheckAllApsStatus = TRUE;
VOID *mReservedApLoopFunc = NULL;
UINTN mReservedTopOfApStack;
volatile UINT32 mNumberToFinish = 0;
+UINTN mApPageTable;
//
// Begin wakeup buffer allocation below 0x88000
@@ -407,14 +410,12 @@ RelocateApLoop (
AsmRelocateApLoopFunc (
MwaitSupport,
CpuMpData->ApTargetCState,
- CpuMpData->PmCodeSegment,
StackStart - ProcessorNumber * AP_SAFE_STACK_SIZE,
(UINTN)&mNumberToFinish,
- CpuMpData->Pm16CodeSegment,
- CpuMpData->SevEsAPBuffer,
- CpuMpData->WakeupBuffer
+ mApPageTable
);
}
+
//
// It should never reach here
//
@@ -476,12 +477,27 @@ InitMpGlobalData (
)
{
EFI_STATUS Status;
- EFI_PHYSICAL_ADDRESS Address;
UINTN ApSafeBufferSize;
UINTN Index;
EFI_GCD_MEMORY_SPACE_DESCRIPTOR MemDesc;
UINTN StackBase;
CPU_INFO_IN_HOB *CpuInfoInHob;
+ IA32_MAP_ATTRIBUTE MapAttribute;
+ IA32_MAP_ATTRIBUTE MapMask;
+ UINTN PageTable;
+ VOID *PageTableBuffer;
+ UINTN PageTableBufferSize;
+
+ MapAttribute.Uint64 = mReservedTopOfApStack;
+ MapAttribute.Bits.Present = 1;
+ MapAttribute.Bits.ReadWrite = 1;
+
+ MapMask.Bits.PageTableBaseAddress = 1;
+ MapMask.Bits.Present = 1;
+ MapMask.Bits.ReadWrite = 1;
+
+ PageTable = 0;
+ PageTableBufferSize = 0;
SaveCpuMpData (CpuMpData);
@@ -544,60 +560,69 @@ InitMpGlobalData (
// Allocating it in advance since memory services are not available in
// Exit Boot Services callback function.
//
- ApSafeBufferSize = EFI_PAGES_TO_SIZE (
- EFI_SIZE_TO_PAGES (
- CpuMpData->AddressMap.RelocateApLoopFuncSize
- )
- );
- Address = BASE_4GB - 1;
- Status = gBS->AllocatePages (
- AllocateMaxAddress,
- EfiReservedMemoryType,
- EFI_SIZE_TO_PAGES (ApSafeBufferSize),
- &Address
- );
- ASSERT_EFI_ERROR (Status);
-
- mReservedApLoopFunc = (VOID *)(UINTN)Address;
- ASSERT (mReservedApLoopFunc != NULL);
-
- //
- // Make sure that the buffer memory is executable if NX protection is enabled
- // for EfiReservedMemoryType.
- //
- // TODO: Check EFI_MEMORY_XP bit set or not once it's available in DXE GCD
- // service.
+ // +------------+
+ // | Ap Loop |
+ // +------------+
+ // | Stack * N |
+ // +------------+ (low address)
//
- Status = gDS->GetMemorySpaceDescriptor (Address, &MemDesc);
- if (!EFI_ERROR (Status)) {
- gDS->SetMemorySpaceAttributes (
- Address,
- ApSafeBufferSize,
- MemDesc.Attributes & (~EFI_MEMORY_XP)
- );
- }
-
ApSafeBufferSize = EFI_PAGES_TO_SIZE (
EFI_SIZE_TO_PAGES (
CpuMpData->CpuCount * AP_SAFE_STACK_SIZE
+ + CpuMpData->AddressMap.RelocateApLoopFuncSize
)
);
- Address = BASE_4GB - 1;
- Status = gBS->AllocatePages (
- AllocateMaxAddress,
- EfiReservedMemoryType,
- EFI_SIZE_TO_PAGES (ApSafeBufferSize),
- &Address
- );
- ASSERT_EFI_ERROR (Status);
- mReservedTopOfApStack = (UINTN)Address + ApSafeBufferSize;
+ mReservedTopOfApStack = (UINTN)AllocateReservedPages (EFI_SIZE_TO_PAGES
(ApSafeBufferSize));
+ ASSERT (mReservedTopOfApStack != 0);
ASSERT ((mReservedTopOfApStack & (UINTN)(CPU_STACK_ALIGNMENT - 1)) == 0);
- CopyMem (
- mReservedApLoopFunc,
- CpuMpData->AddressMap.RelocateApLoopFuncAddress,
- CpuMpData->AddressMap.RelocateApLoopFuncSize
- );
+ ASSERT ((AP_SAFE_STACK_SIZE & (CPU_STACK_ALIGNMENT - 1)) == 0);
+
+ mReservedApLoopFunc = (VOID *)(mReservedTopOfApStack + CpuMpData->CpuCount *
AP_SAFE_STACK_SIZE);
+ if (StandardSignatureIsAuthenticAMD ()) {
+ CopyMem (
+ mReservedApLoopFunc,
+ CpuMpData->AddressMap.RelocateApLoopFuncAddressAmd,
+ CpuMpData->AddressMap.RelocateApLoopFuncSizeAmd
+ );
+ } else {
+ CopyMem (
+ mReservedApLoopFunc,
+ CpuMpData->AddressMap.RelocateApLoopFuncAddress,
+ CpuMpData->AddressMap.RelocateApLoopFuncSize
+ );
+ //
+ // Allocate reserved memory for page table
+ //
+ Status = PageTableMap (
+ &PageTable,
+ Paging4Level,
+ NULL,
+ &PageTableBufferSize,
+ mReservedTopOfApStack,
+ ApSafeBufferSize,
+ &MapAttribute,
+ &MapMask
+ );
+ ASSERT (Status == EFI_BUFFER_TOO_SMALL);
+ DEBUG ((DEBUG_ERROR, "AP Page Table Buffer Size = %x\n",
PageTableBufferSize));
+
+ PageTableBuffer = AllocateReservedPages (EFI_SIZE_TO_PAGES
(PageTableBufferSize));
+ ASSERT (PageTableBuffer != NULL);
+ Status = PageTableMap (
+ &PageTable,
+ Paging4Level,
+ PageTableBuffer,
+ &PageTableBufferSize,
+ mReservedTopOfApStack,
+ ApSafeBufferSize,
+ &MapAttribute,
+ &MapMask
+ );
+ ASSERT_EFI_ERROR (Status);
+ mApPageTable = PageTable;
+ mReservedTopOfApStack += CpuMpData->CpuCount * AP_SAFE_STACK_SIZE;
+ }
Status = gBS->CreateEvent (
EVT_TIMER | EVT_NOTIFY_SIGNAL,
diff --git a/UefiCpuPkg/Library/MpInitLib/MpLib.h
b/UefiCpuPkg/Library/MpInitLib/MpLib.h
index 1102003a93..0ffad29f1a 100644
--- a/UefiCpuPkg/Library/MpInitLib/MpLib.h
+++ b/UefiCpuPkg/Library/MpInitLib/MpLib.h
@@ -392,12 +392,9 @@ typedef
(EFIAPI *ASM_RELOCATE_AP_LOOP)(
IN BOOLEAN MwaitSupport,
IN UINTN ApTargetCState,
- IN UINTN PmCodeSegment,
IN UINTN TopOfApStack,
IN UINTN NumberToFinish,
- IN UINTN Pm16CodeSegment,
- IN UINTN SevEsAPJumpTable,
- IN UINTN WakeupBuffer
+ IN UINTN Cr3
);
/**
diff --git a/UefiCpuPkg/Library/MpInitLib/X64/MpFuncs.nasm
b/UefiCpuPkg/Library/MpInitLib/X64/MpFuncs.nasm
index 87b23b482e..78ac5427a7 100644
--- a/UefiCpuPkg/Library/MpInitLib/X64/MpFuncs.nasm
+++ b/UefiCpuPkg/Library/MpInitLib/X64/MpFuncs.nasm
@@ -279,120 +279,42 @@ CProcedureInvoke:
RendezvousFunnelProcEnd:
;-------------------------------------------------------------------------------------
-; AsmRelocateApLoop (MwaitSupport, ApTargetCState, PmCodeSegment,
TopOfApStack, CountTofinish, Pm16CodeSegment, SevEsAPJumpTable, WakeupBuffer);
+; AsmRelocateApLoop (MwaitSupport, ApTargetCState, TopOfApStack,
CountTofinish, Cr3);
+; This function is called during the finalizaiton of Mp initialization before
booting
+; to OS, and aim to put Aps either in Mwait or HLT.
;-------------------------------------------------------------------------------------
-AsmRelocateApLoopStart:
-BITS 64
- cmp qword [rsp + 56], 0 ; SevEsAPJumpTable
- je NoSevEs
-
- ;
- ; Perform some SEV-ES related setup before leaving 64-bit mode
- ;
- push rcx
- push rdx
-
- ;
- ; Get the RDX reset value using CPUID
- ;
- mov rax, 1
- cpuid
- mov rsi, rax ; Save off the reset value for RDX
-
- ;
- ; Prepare the GHCB for the AP_HLT_LOOP VMGEXIT call
- ; - Must be done while in 64-bit long mode so that writes to
- ; the GHCB memory will be unencrypted.
- ; - No NAE events can be generated once this is set otherwise
- ; the AP_RESET_HOLD SW_EXITCODE will be overwritten.
- ;
- mov rcx, 0xc0010130
- rdmsr ; Retrieve current GHCB address
- shl rdx, 32
- or rdx, rax
-
- mov rdi, rdx
- xor rax, rax
- mov rcx, 0x800
- shr rcx, 3
- rep stosq ; Clear the GHCB
-
- mov rax, 0x80000004 ; VMGEXIT AP_RESET_HOLD
- mov [rdx + 0x390], rax
- mov rax, 114 ; Set SwExitCode valid bit
- bts [rdx + 0x3f0], rax
- inc rax ; Set SwExitInfo1 valid bit
- bts [rdx + 0x3f0], rax
- inc rax ; Set SwExitInfo2 valid bit
- bts [rdx + 0x3f0], rax
+; +----------------+
+; | Cr3 | rsp+40
+; +----------------+
+; | CountTofinish | r9
+; +----------------+
+; | TopOfApStack | r8
+; +----------------+
+; | ApTargetCState | rdx
+; +----------------+
+; | MwaitSupport | rcx
+; +----------------+
+; | the return |
+; +----------------+ low address
- pop rdx
- pop rcx
-
-NoSevEs:
- cli ; Disable interrupt before switching to
32-bit mode
- mov rax, [rsp + 40] ; CountTofinish
+AsmRelocateApLoopStart:
+ mov rax, r9 ; CountTofinish
lock dec dword [rax] ; (*CountTofinish)--
- mov r10, [rsp + 48] ; Pm16CodeSegment
- mov rax, [rsp + 56] ; SevEsAPJumpTable
- mov rbx, [rsp + 64] ; WakeupBuffer
- mov rsp, r9 ; TopOfApStack
-
- push rax ; Save SevEsAPJumpTable
- push rbx ; Save WakeupBuffer
- push r10 ; Save Pm16CodeSegment
- push rcx ; Save MwaitSupport
- push rdx ; Save ApTargetCState
-
- lea rax, [PmEntry] ; rax <- The start address of transition code
-
- push r8
- push rax
-
- ;
- ; Clear R8 - R15, for reset, before going into 32-bit mode
- ;
- xor r8, r8
- xor r9, r9
- xor r10, r10
- xor r11, r11
- xor r12, r12
- xor r13, r13
- xor r14, r14
- xor r15, r15
-
- ;
- ; Far return into 32-bit mode
- ;
- retfq
-
-BITS 32
-PmEntry:
- mov eax, cr0
- btr eax, 31 ; Clear CR0.PG
- mov cr0, eax ; Disable paging and caches
-
- mov ecx, 0xc0000080
- rdmsr
- and ah, ~ 1 ; Clear LME
- wrmsr
- mov eax, cr4
- and al, ~ (1 << 5) ; Clear PAE
- mov cr4, eax
-
- pop edx
- add esp, 4
- pop ecx,
- add esp, 4
+ mov rax, [rsp + 40] ; Cr3
+ ; Do not push on old stack, since old stack is not mapped
+ ; in the page table pointed by cr3
+ mov cr3, rax
+ mov rsp, r8 ; TopOfApStack
MwaitCheck:
cmp cl, 1 ; Check mwait-monitor support
jnz HltLoop
- mov ebx, edx ; Save C-State to ebx
+ mov rbx, rdx ; Save C-State to ebx
+
MwaitLoop:
cli
- mov eax, esp ; Set Monitor Address
+ mov rax, rsp ; Set Monitor Address
xor ecx, ecx ; ecx = 0
xor edx, edx ; edx = 0
monitor
@@ -402,49 +324,10 @@ MwaitLoop:
jmp MwaitLoop
HltLoop:
- pop edx ; PM16CodeSegment
- add esp, 4
- pop ebx ; WakeupBuffer
- add esp, 4
- pop eax ; SevEsAPJumpTable
- add esp, 4
- cmp eax, 0 ; Check for SEV-ES
- je DoHlt
-
- cli
- ;
- ; SEV-ES is enabled, use VMGEXIT (GHCB information already
- ; set by caller)
- ;
-BITS 64
- rep vmmcall
-BITS 32
-
- ;
- ; Back from VMGEXIT AP_HLT_LOOP
- ; Push the FLAGS/CS/IP values to use
- ;
- push word 0x0002 ; EFLAGS
- xor ecx, ecx
- mov cx, [eax + 2] ; CS
- push cx
- mov cx, [eax] ; IP
- push cx
- push word 0x0000 ; For alignment, will be discarded
-
- push edx
- push ebx
-
- mov edx, esi ; Restore RDX reset value
-
- retf
-
-DoHlt:
cli
hlt
- jmp DoHlt
+ jmp HltLoop
-BITS 64
AsmRelocateApLoopEnd:
;-------------------------------------------------------------------------------------
--
2.36.1.windows.1
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