IntelFsp2Pkg: BaseFspSwitchStackLib Support for X64

[mirror_edk2.git] / IntelFsp2Pkg / Library / BaseFspSwitchStackLib / X64 / Stack.nasm

diff --git a/IntelFsp2Pkg/Library/BaseFspSwitchStackLib/X64/Stack.nasm b/IntelFsp2Pkg/Library/BaseFspSwitchStackLib/X64/Stack.nasm
new file mode 100644 (file)
index 0000000..bd36fe4
--- /dev/null
+++ b/IntelFsp2Pkg/Library/BaseFspSwitchStackLib/X64/Stack.nasm
@@ -0,0 +1,72 @@
+;------------------------------------------------------------------------------\r
+;\r
+; Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>\r
+; SPDX-License-Identifier: BSD-2-Clause-Patent\r
+;\r
+; Abstract:\r
+;\r
+;   Switch the stack from temporary memory to permanent memory.\r
+;\r
+;------------------------------------------------------------------------------\r
+\r
+    SECTION .text\r
+\r
+%include    "PushPopRegsNasm.inc"\r
+\r
+extern ASM_PFX(SwapStack)\r
+\r
+;------------------------------------------------------------------------------\r
+; UINT32\r
+; EFIAPI\r
+; Pei2LoaderSwitchStack (\r
+;   VOID\r
+;   )\r
+;------------------------------------------------------------------------------\r
+global ASM_PFX(Pei2LoaderSwitchStack)\r
+ASM_PFX(Pei2LoaderSwitchStack):\r
+    xor     rax, rax\r
+    jmp     ASM_PFX(FspSwitchStack)\r
+\r
+;------------------------------------------------------------------------------\r
+; UINT32\r
+; EFIAPI\r
+; Loader2PeiSwitchStack (\r
+;   VOID\r
+;   )\r
+;------------------------------------------------------------------------------\r
+global ASM_PFX(Loader2PeiSwitchStack)\r
+ASM_PFX(Loader2PeiSwitchStack):\r
+    jmp     ASM_PFX(FspSwitchStack)\r
+\r
+;------------------------------------------------------------------------------\r
+; UINT32\r
+; EFIAPI\r
+; FspSwitchStack (\r
+;   VOID\r
+;   )\r
+;------------------------------------------------------------------------------\r
+global ASM_PFX(FspSwitchStack)\r
+ASM_PFX(FspSwitchStack):\r
+    ; Save current contexts\r
+    push    rdx     ; ApiParam2\r
+    push    rcx     ; ApiParam1\r
+    push    rax     ; FspInfoHeader\r
+    pushfq\r
+    cli\r
+    PUSHA_64\r
+    sub     rsp, 16\r
+    sidt    [rsp]\r
+\r
+    ; Load new stack\r
+    mov     rcx, rsp\r
+    call    ASM_PFX(SwapStack)\r
+    mov     rsp, rax\r
+\r
+    ; Restore previous contexts\r
+    lidt    [rsp]\r
+    add     rsp, 16\r
+    POPA_64\r
+    popfq\r
+    add     rsp, 24 ; FspInfoHeader + ApiParam[2]\r
+    ret\r
+\r