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| ; @file
| ; Copyright (c) 2006 - 2019 Intel Corporation. All rights reserved. <BR>
| ;
| ; SPDX-License-Identifier: BSD-2-Clause-Patent
| ;
|
| DEFAULT REL
| SECTION .text
|
| ;------------------------------------------------------------------------------
| ; VOID
| ; EFIAPI
| ; JumpToKernel (
| ; VOID *KernelStart, // rcx
| ; VOID *KernelBootParams // rdx
| ; );
| ;------------------------------------------------------------------------------
| global ASM_PFX(JumpToKernel)
| ASM_PFX(JumpToKernel):
|
| ; Set up for executing kernel. BP in %esi, entry point on the stack
| ; (64-bit when the 'ret' will use it as 32-bit, but we're little-endian)
| mov rsi, rdx
| push rcx
|
| ; Jump into the compatibility mode CS
| push 0x10
| lea rax, [.0]
| push rax
| DB 0x48, 0xcb ; retfq
|
| .0:
| ; Now in compatibility mode.
|
| DB 0xb8, 0x18, 0x0, 0x0, 0x0 ; movl $0x18, %eax
| DB 0x8e, 0xd8 ; movl %eax, %ds
| DB 0x8e, 0xc0 ; movl %eax, %es
| DB 0x8e, 0xe0 ; movl %eax, %fs
| DB 0x8e, 0xe8 ; movl %eax, %gs
| DB 0x8e, 0xd0 ; movl %eax, %ss
|
| ; Disable paging
| DB 0xf, 0x20, 0xc0 ; movl %cr0, %eax
| DB 0xf, 0xba, 0xf8, 0x1f ; btcl $31, %eax
| DB 0xf, 0x22, 0xc0 ; movl %eax, %cr0
|
| ; Disable long mode in EFER
| DB 0xb9, 0x80, 0x0, 0x0, 0xc0 ; movl $0x0c0000080, %ecx
| DB 0xf, 0x32 ; rdmsr
| DB 0xf, 0xba, 0xf8, 0x8 ; btcl $8, %eax
| DB 0xf, 0x30 ; wrmsr
|
| ; Disable PAE
| DB 0xf, 0x20, 0xe0 ; movl %cr4, %eax
| DB 0xf, 0xba, 0xf8, 0x5 ; btcl $5, %eax
| DB 0xf, 0x22, 0xe0 ; movl %eax, %cr4
|
| DB 0x31, 0xed ; xor %ebp, %ebp
| DB 0x31, 0xff ; xor %edi, %edi
| DB 0x31, 0xdb ; xor %ebx, %ebx
| DB 0xc3 ; ret
|
| ;------------------------------------------------------------------------------
| ; VOID
| ; EFIAPI
| ; JumpToUefiKernel (
| ; EFI_HANDLE ImageHandle, // rcx
| ; EFI_SYSTEM_TABLE *SystemTable, // rdx
| ; VOID *KernelBootParams // r8
| ; VOID *KernelStart, // r9
| ; );
| ;------------------------------------------------------------------------------
| global ASM_PFX(JumpToUefiKernel)
| ASM_PFX(JumpToUefiKernel):
|
| mov rdi, rcx
| mov rsi, rdx
| mov rdx, r8
| xor rax, rax
| mov eax, [r8 + 0x264]
| add r9, rax
| add r9, 0x200
| call r9
| ret
|
|
|
