#------------------------------------------------------------------------------\r
#\r
-# Copyright (c) 2006 - 2008, Intel Corporation\r
-# All rights reserved. This program and the accompanying materials\r
+# Copyright (c) 2006 - 2009, Intel Corporation. All rights reserved.<BR>\r
+# This program and the accompanying materials\r
# are licensed and made available under the terms and conditions of the BSD License\r
# which accompanies this distribution. The full text of the license may be found at\r
-# http://opensource.org/licenses/bsd-license.php\r
+# http://opensource.org/licenses/bsd-license.php.\r
#\r
# THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
# WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
ASM_GLOBAL ASM_PFX(InternalX86DisablePaging64)\r
ASM_PFX(InternalX86DisablePaging64):\r
cli \r
- lea L1(%rip), %r10\r
+ lea L1(%rip), %rsi # rsi <- The start address of transition code\r
+ mov 0x28(%rsp), %edi # rdi <- New stack\r
+ lea _mTransitionEnd(%rip), %rax # rax <- end of transition code\r
+ sub %rsi, %rax # rax <- The size of transition piece code\r
+ add $4, %rax # round rax up to the next 4 byte boundary\r
+ and $0xfc, %al\r
+ sub %rax, %rdi # rdi <- use stack to hold transition code \r
+ mov %edi, %r10d # r10 <- The start address of transicition code below 4G\r
+ push %rcx # save rcx to stack\r
+ mov %rax, %rcx # rcx <- The size of transition piece code\r
+ rep\r
+ movsb # copy transition code to (new stack - 64byte) below 4G\r
+ pop %rcx # restore rcx\r
+ \r
mov %r8d, %esi \r
mov %r9d, %edi \r
- mov 0x28(%rsp), %eax # eax <- New Stack\r
+ mov %r10d, %eax\r
+ sub $4, %eax\r
push %rcx # push Cs to stack\r
- push %r10\r
+ push %r10 # push address of transition code on stack \r
.byte 0x48, 0xcb # retq: Use far return to load CS register from stack\r
# (Use raw byte code since some GNU assemblers generates incorrect code for "retq") \r
L1:\r
mov %eax,%esp # set up new stack\r
mov %cr0,%rax\r
- btr $0x1f,%eax\r
+ btr $0x1f,%eax # clear CR0.PG\r
mov %rax,%cr0 # disable paging\r
\r
- mov %rdx,%rbx # save EntryPoint to rbx, for rdmsr will overwrite rdx\r
+ mov %edx,%ebx # save EntryPoint to ebx, for rdmsr will overwrite edx\r
mov $0xc0000080,%ecx\r
rdmsr \r
and $0xfe,%ah # clear LME\r
callq *%rbx # transfer control to EntryPoint\r
jmp . # no one should get here\r
\r
+_mTransitionEnd :\r