diff options
Diffstat (limited to 'OvmfPkg/Library/LoadLinuxLib/X64/JumpToKernel.S')
| -rw-r--r-- | OvmfPkg/Library/LoadLinuxLib/X64/JumpToKernel.S | 67 |
1 files changed, 64 insertions, 3 deletions
diff --git a/OvmfPkg/Library/LoadLinuxLib/X64/JumpToKernel.S b/OvmfPkg/Library/LoadLinuxLib/X64/JumpToKernel.S index 9ae755b0..056e3c01 100644 --- a/OvmfPkg/Library/LoadLinuxLib/X64/JumpToKernel.S +++ b/OvmfPkg/Library/LoadLinuxLib/X64/JumpToKernel.S @@ -1,6 +1,6 @@ #------------------------------------------------------------------------------
#
-# Copyright (c) 2006 - 2011, Intel Corporation. All rights reserved.<BR>
+# Copyright (c) 2006 - 2013, 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
@@ -13,6 +13,7 @@ #------------------------------------------------------------------------------
ASM_GLOBAL ASM_PFX(JumpToKernel)
+ASM_GLOBAL ASM_PFX(JumpToUefiKernel)
#------------------------------------------------------------------------------
# VOID
@@ -23,8 +24,68 @@ ASM_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)
+ movq %rdx, %rsi
+ pushq %rcx
+
+ // Jump into the compatibility mode CS
+ pushq $0x10
+ leaq 1f(%rip), %rax
+ pushq %rax
+ .byte 0x48, 0xcb // retfq
+
+1: // Now in compatibility mode
+.code32
+ movl $0x18, %eax
+ movl %eax, %ds
+ movl %eax, %es
+ movl %eax, %fs
+ movl %eax, %gs
+ movl %eax, %ss
+
+ // Disable paging
+ movl %cr0, %eax
+ btcl $31, %eax
+ movl %eax, %cr0
+
+ // Disable long mode in EFER
+ movl $0x0c0000080, %ecx
+ rdmsr
+ btcl $8, %eax
+ wrmsr
+
+ // Disable PAE
+ movl %cr4, %eax
+ btcl $5, %eax
+ movl %eax, %cr4
+
+ // Zero registers and 'return' to kernel
+ xorl %ebp, %ebp
+ xorl %edi, %edi
+ xorl %ebx, %ebx
+ ret
+.code64
+
+#------------------------------------------------------------------------------
+# VOID
+# EFIAPI
+# JumpToUefiKernel (
+# EFI_HANDLE ImageHandle, // rcx
+# EFI_SYSTEM_TABLE *SystemTable, // rdx
+# VOID *KernelBootParams, // r8
+# VOID *KernelStart // r9
+# );
+#------------------------------------------------------------------------------
+ASM_PFX(JumpToUefiKernel):
+ movq %rcx, %rdi
movq %rdx, %rsi
- addq $0x200, %rcx
- callq %rcx
+ movq %r8, %rdx
+ xor %rax, %rax
+ movl 0x264(%r8), %eax
+ addq %rax, %r9
+ addq $0x200, %r9
+ callq %r9
ret
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