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| author | Jordan Justen <jordan.l.justen@intel.com> | 2014-11-13 18:24:59 +0000 |
|---|---|---|
| committer | jljusten <jljusten@Edk2> | 2014-11-13 18:24:59 +0000 |
| commit | fab82c1873b792bce33fb22c32db71324fc0ac3b (patch) | |
| tree | bfda1f1c1e5e7b3f8353fd893828fa9e39dd5431 /UefiCpuPkg/CpuDxe/X64 | |
| parent | 1535c888c6f06bb35881e83cd7ee49fb8554942b (diff) | |
| download | edk2-fab82c1873b792bce33fb22c32db71324fc0ac3b.tar.gz edk2-fab82c1873b792bce33fb22c32db71324fc0ac3b.tar.bz2 edk2-fab82c1873b792bce33fb22c32db71324fc0ac3b.zip | |
UefiCpuPkg/CpuDxe: Add stackless assembly AP entry points
The AP startup code simply jumps into this code with the CpuDxe driver
without setting up a stack for the processor.
Therefore, this code must setup the stack before calling into C code.
This is the basic flow:
* AP enters CpuDxe driver code (AsmApEntryPoint) without stack
- AP grabs a lock
- AP sets up stack
- AP calls CpuMp.c:ApEntryPointInC
- If ApEntryPointInC returns, the lock is freed, and another AP may
run
- The AP C code may call AsmApDoneWithCommonStack to indicate that
the AP is no longer using the stack, and another may therefore
proceed to use the stack and then call ApEntryPointInC
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Jeff Fan <jeff.fan@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16347 6f19259b-4bc3-4df7-8a09-765794883524
Diffstat (limited to 'UefiCpuPkg/CpuDxe/X64')
| -rw-r--r-- | UefiCpuPkg/CpuDxe/X64/MpAsm.asm | 76 | ||||
| -rw-r--r-- | UefiCpuPkg/CpuDxe/X64/MpAsm.nasm | 70 |
2 files changed, 146 insertions, 0 deletions
diff --git a/UefiCpuPkg/CpuDxe/X64/MpAsm.asm b/UefiCpuPkg/CpuDxe/X64/MpAsm.asm new file mode 100644 index 0000000000..308de51330 --- /dev/null +++ b/UefiCpuPkg/CpuDxe/X64/MpAsm.asm @@ -0,0 +1,76 @@ +;------------------------------------------------------------------------------
+;
+; Copyright (c) 2006 - 2014, Intel Corporation. All rights reserved.<BR>
+; This program and the accompanying materials
+; are licensed and made available under the terms and conditions of the BSD License
+; which accompanies this distribution. The full text of the license may be found at
+; http://opensource.org/licenses/bsd-license.php.
+;
+; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+;
+;------------------------------------------------------------------------------
+
+#include <Base.h>
+
+extern ASM_PFX(mTopOfApCommonStack):QWORD
+extern ASM_PFX(ApEntryPointInC):PROC
+
+.data
+
+;
+; This lock only allows one AP to use the mTopOfApCommonStack stack at a time
+;
+ApStackLock:
+ dd 0
+
+.code
+
+;------------------------------------------------------------------------------
+; VOID
+; EFIAPI
+; AsmApEntryPoint (
+; VOID
+; );
+;------------------------------------------------------------------------------
+ASM_PFX(AsmApEntryPoint) PROC PUBLIC
+
+ cli
+AsmApEntryPointAcquireLock:
+lock bts dword ptr [ApStackLock], 0
+ pause
+ jc AsmApEntryPointAcquireLock
+
+ mov rsp, [ASM_PFX(mTopOfApCommonStack)]
+ call ASM_PFX(ApEntryPointInC)
+
+ cli
+
+lock btc dword ptr [ApStackLock], 0
+
+ mov eax, 100h
+AsmApEntryPointShareLock:
+ pause
+ dec eax
+ jnz AsmApEntryPointShareLock
+
+ jmp ASM_PFX(AsmApEntryPoint)
+
+ASM_PFX(AsmApEntryPoint) ENDP
+
+;------------------------------------------------------------------------------
+; VOID
+; EFIAPI
+; AsmApDoneWithCommonStack (
+; VOID
+; );
+;------------------------------------------------------------------------------
+ASM_PFX(AsmApDoneWithCommonStack) PROC PUBLIC
+
+lock btc dword ptr [ApStackLock], 0
+ ret
+
+ASM_PFX(AsmApDoneWithCommonStack) ENDP
+
+END
+
diff --git a/UefiCpuPkg/CpuDxe/X64/MpAsm.nasm b/UefiCpuPkg/CpuDxe/X64/MpAsm.nasm new file mode 100644 index 0000000000..e3dc248002 --- /dev/null +++ b/UefiCpuPkg/CpuDxe/X64/MpAsm.nasm @@ -0,0 +1,70 @@ +;------------------------------------------------------------------------------
+;
+; Copyright (c) 2006 - 2014, Intel Corporation. All rights reserved.<BR>
+; This program and the accompanying materials
+; are licensed and made available under the terms and conditions of the BSD License
+; which accompanies this distribution. The full text of the license may be found at
+; http://opensource.org/licenses/bsd-license.php.
+;
+; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+;
+;------------------------------------------------------------------------------
+
+extern ASM_PFX(mTopOfApCommonStack)
+extern ASM_PFX(ApEntryPointInC)
+
+DEFAULT REL
+
+SECTION .data
+
+;
+; This lock only allows one AP to use the mTopOfApCommonStack stack at a time
+;
+ApStackLock:
+ dd 0
+
+SECTION .text
+
+;------------------------------------------------------------------------------
+; VOID
+; EFIAPI
+; AsmApEntryPoint (
+; VOID
+; );
+;------------------------------------------------------------------------------
+global ASM_PFX(AsmApEntryPoint)
+ASM_PFX(AsmApEntryPoint):
+ cli
+AsmApEntryPointAcquireLock:
+lock bts dword [ApStackLock], 0
+ pause
+ jc AsmApEntryPointAcquireLock
+
+ mov rsp, [ASM_PFX(mTopOfApCommonStack)]
+ call ASM_PFX(ApEntryPointInC)
+
+ cli
+
+lock btc dword [ApStackLock], 0
+
+ mov eax, 0x100
+AsmApEntryPointShareLock:
+ pause
+ dec eax
+ jnz AsmApEntryPointShareLock
+
+ jmp ASM_PFX(AsmApEntryPoint)
+
+;------------------------------------------------------------------------------
+; VOID
+; EFIAPI
+; AsmApDoneWithCommonStack (
+; VOID
+; );
+;------------------------------------------------------------------------------
+global ASM_PFX(AsmApDoneWithCommonStack)
+ASM_PFX(AsmApDoneWithCommonStack):
+lock btc dword [ApStackLock], 0
+ ret
+
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