Signed-off-by: Min Xu <min.m...@intel.com> --- OvmfPkg/ResetVector/Main.asm | 103 +++++++++++++++++++++++++++++++++++ 1 file changed, 103 insertions(+) create mode 100644 OvmfPkg/ResetVector/Main.asm
diff --git a/OvmfPkg/ResetVector/Main.asm b/OvmfPkg/ResetVector/Main.asm new file mode 100644 index 000000000000..ae90a148fce7 --- /dev/null +++ b/OvmfPkg/ResetVector/Main.asm @@ -0,0 +1,103 @@ +;------------------------------------------------------------------------------ +; @file +; Main routine of the pre-SEC code up through the jump into SEC +; +; Copyright (c) 2008 - 2009, Intel Corporation. All rights reserved.<BR> +; SPDX-License-Identifier: BSD-2-Clause-Patent +; +;------------------------------------------------------------------------------ + + +BITS 16 + +; +; Modified: EBX, ECX, EDX, EBP +; +; @param[in,out] RAX/EAX Initial value of the EAX register +; (BIST: Built-in Self Test) +; @param[in,out] DI 'BP': boot-strap processor, or +; 'AP': application processor +; @param[out] RBP/EBP Address of Boot Firmware Volume (BFV) +; @param[out] DS Selector allowing flat access to all addresses +; @param[out] ES Selector allowing flat access to all addresses +; @param[out] FS Selector allowing flat access to all addresses +; @param[out] GS Selector allowing flat access to all addresses +; @param[out] SS Selector allowing flat access to all addresses +; +; @return None This routine jumps to SEC and does not return +; +Main16: + OneTimeCall EarlyInit16 + + ; + ; Transition the processor from 16-bit real mode to 32-bit flat mode + ; + OneTimeCall TransitionFromReal16To32BitFlat + +BITS 32 + + ; + ; Search for the Boot Firmware Volume (BFV) + ; + OneTimeCall Flat32SearchForBfvBase + + ; + ; EBP - Start of BFV + ; + + ; + ; Search for the SEC entry point + ; + OneTimeCall Flat32SearchForSecEntryPoint + + ; + ; ESI - SEC Core entry point + ; EBP - Start of BFV + ; + +%ifdef ARCH_IA32 + + ; + ; Restore initial EAX value into the EAX register + ; + mov eax, esp + + ; + ; Jump to the 32-bit SEC entry point + ; + jmp esi + +%else + + ; + ; Transition the processor from 32-bit flat mode to 64-bit flat mode + ; + OneTimeCall Transition32FlatTo64Flat + +BITS 64 + + ; + ; Some values were calculated in 32-bit mode. Make sure the upper + ; 32-bits of 64-bit registers are zero for these values. + ; + mov rax, 0x00000000ffffffff + and rsi, rax + and rbp, rax + and rsp, rax + + ; + ; RSI - SEC Core entry point + ; RBP - Start of BFV + ; + + ; + ; Restore initial EAX value into the RAX register + ; + mov rax, rsp + + ; + ; Jump to the 64-bit SEC entry point + ; + jmp rsi + +%endif -- 2.29.2.windows.2 -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#81473): https://edk2.groups.io/g/devel/message/81473 Mute This Topic: https://groups.io/mt/86085721/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
