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#------------------------------------------------------------------------------
#*
#* Copyright (c) 2006, Intel Corporation
#* All rights reserved. This program and the accompanying materials
#* are licensed and made available under the terms and conditions of the BSD License
#* which accompanies this distribution. The full text of the license may be found at
#* http://opensource.org/licenses/bsd-license.php
#*
#* THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
#* WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
#*
#* LongMode.S
#*
#* Abstract:
#*
#* Transition from 32-bit protected mode EFI environment into x64
#* 64-bit bit long mode.
#*
#* This file is not fully ported or operational.
#*
#------------------------------------------------------------------------------
.686p:
#.MODEL flat
#
# Create the exception handler code in IA32 C code
#
.code:
.stack:
.MMX:
.XMM:
.global _LoadGo64Gdt;
_LoadGo64Gdt:
pushl %ebp # C prolog
pushl %edi
movl %esp, %ebp
#
# Disable interrupts
#
cli
#
# Reload the selectors
# Note:
# Make the Selectors 64-bit ready
#
movl gdtr, %edi # Load GDT register
movw %cs, %ax # Get the selector data from our code image
mov %ax, %es
# FIXME MISMATCH: " lgdt FWORD PTR es:[edi] "
.byte 0x67
.byte 0xea # Far Jump Offset:Selector to reload CS
# FIXME MISMATCH: " dd OFFSET DataSelectorRld"
# FIXME MISMATCH: " dw LINEAR_CODE_SEL "
DataSelectorRld:
movw SYS_DATA_SEL, %ax # Update the Base for the new selectors, too
movw %ax, %ds
movw %ax, %es
movw %ax, %fs
movw %ax, %gs
movw %ax, %ss
popl %edi
popl %ebp
ret
#_LoadGo64Gdt ENDP
# VOID
# ActivateLongMode (
# IN EFI_PHYSICAL_ADDRESS PageTables,
# IN EFI_PHYSICAL_ADDRESS HobStart,
# IN EFI_PHYSICAL_ADDRESS Stack,
# IN EFI_PHYSICAL_ADDRESS PpisNeededByDxeIplEntryPoint,
# IN EFI_PHYSICAL_ADDRESS DxeCoreEntryPoint
# )
#
# Input: [ebp][0h] = Original ebp
# [ebp][4h] = Return address
# [ebp][8h] = PageTables
# [ebp][10h] = HobStart
# [ebp][18h] = Stack
# [ebp][20h] = CodeEntryPoint1 <--- Call this first (for each call, pass HOB pointer)
# [ebp][28h] = CodeEntryPoint2 <--- Call this second
#
#
.global _ActivateLongMode;
_ActivateLongMode:
pushl %ebp # C prolog
movl %esp, %ebp
#
# Use CPUID to determine if the processor supports long mode.
#
movl $0x80000000, %eax # Extended-function code 8000000h.
cpuid # Is largest extended function
cmpl $0x80000000, %eax # any function > 80000000h?
jbe no_long_mode # If not, no long mode.
movl $0x80000001, %eax # Extended-function code 8000001h.
cpuid # Now EDX = extended-features flags.
btl $29, %edx # Test if long mode is supported.
jnc no_long_mode # Exit if not supported.
#
# Enable the 64-bit page-translation-table entries by
# setting CR4.PAE=1 (this is _required_ before activating
# long mode). Paging is not enabled until after long mode
# is enabled.
#
movl %cr4, %eax
btsl $5, %eax
movl %eax, %cr4
#
# Get the long-mode page tables, and initialize the
# 64-bit CR3 (page-table base address) to point to the base
# of the PML4 page table. The PML4 page table must be located
# below 4 Gbytes because only 32 bits of CR3 are loaded when
# the processor is not in 64-bit mode.
#
movl 0x8(%ebp), %eax # Get Page Tables
movl %eax, %cr3 # Initialize CR3 with PML4 base.
#
# Enable long mode (set EFER.LME=1).
#
movl $0xc0000080, %ecx # EFER MSR number.
rdmsr # Read EFER.
btsl $8, %eax # Set LME=1.
wrmsr # Write EFER.
#
# Enable paging to activate long mode (set CR0.PG=1)
#
movl %cr0, %eax # Read CR0.
btsl $31, %eax # Set PG=1.
movl %eax, %cr0 # Write CR0.
jmp go_to_long_mode
go_to_long_mode:
#
# This is the next instruction after enabling paging. Jump to long mode
#
.byte 0x67
.byte 0xea # Far Jump Offset:Selector to reload CS
#FIXME MISMATCH: " dd OFFSET in_long_mode"
#FIXME MISMATCH: " dw SYS_CODE64_SEL "
in_long_mode:
movw SYS_DATA64_SEL, %ax
movw %ax, %es
movw %ax, %ss
movw %ax, %ds
jmp .
#
# We're in long mode, so marshall the arguments to call the
# passed in function pointers
# Recall
# [ebp][10h] = HobStart
# [ebp][18h] = Stack
# [ebp][20h] = PpisNeededByDxeIplEntryPoint <--- Call this first (for each call, pass HOB pointer)
# [ebp][28h] = DxeCoreEntryPoint <--- Call this second
#
.byte 0x48
movl 0x18(%ebp), %ebx # Setup the stack
.byte 0x48
movl %ebx, %esp # On a new stack now
## 00000905 FF D0 call rax
.byte 0x48
movl 0x10(%ebp), %ecx # Pass Hob Start in RCX
.byte 0x48
movl 0x28(%ebp), %eax # Get the function pointer for
# DxeCoreEntryPoint into EAX
## 00000905 FF D0 call rax
.byte 0xff
.byte 0xd0
#
# WE SHOULD NEVER GET HERE!!!!!!!!!!!!!
#
no_long_mode:
jmp no_long_mode
#_ActivateLongMode ENDP
.align 16
gdtr: #FIXME MISMATCH: "gdtr dw _GDT_END - _GDT_BASE - 1 "
#FIXME MISMATCH: " dd OFFSET _GDT_BASE "
#-----------------------------------------------------------------------------;
# global descriptor table (GDT)
#-----------------------------------------------------------------------------;
.align 16
.global _GDT_BASE
_GDT_BASE:
# null descriptor
.equ NULL_SEL, .-_GDT_BASE # Selector [0]
.word 0 # limit 15:0
.word 0 # base 15:0
.byte 0 # base 23:16
.byte 0 # type
.byte 0 # limit 19:16, flags
.byte 0 # base 31:24
# linear data segment descriptor
.equ LINEAR_SEL, .-_GDT_BASE # Selector [0x8]
.word 0xFFFF # limit 0xFFFFF
.word 0 # base 0
.byte 0
.byte 0x92 # present, ring 0, data, expand-up, writable
.byte 0xCF # page-granular, 32-bit
.byte 0
# linear code segment descriptor
.equ LINEAR_CODE_SEL, .-_GDT_BASE # Selector [0x10]
.word 0xFFFF # limit 0xFFFFF
.word 0 # base 0
.byte 0
.byte 0x9F # present, ring 0, data, expand-up, writable
.byte 0xCF # page-granular, 32-bit
.byte 0
# system data segment descriptor
.equ SYS_DATA_SEL, .-_GDT_BASE # Selector [0x18]
.word 0xFFFF # limit 0xFFFFF
.word 0 # base 0
.byte 0
.byte 0x93 # present, ring 0, data, expand-up, writable
.byte 0xCF # page-granular, 32-bit
.byte 0
# system code segment descriptor
.equ SYS_CODE_SEL, .-_GDT_BASE # Selector [0x20]
.word 0xFFFF # limit 0xFFFFF
.word 0 # base 0
.byte 0
.byte 0x9A # present, ring 0, data, expand-up, writable
.byte 0xCF # page-granular, 32-bit
.byte 0
# spare segment descriptor
.equ SPARE3_SEL, .-_GDT_BASE # Selector [0x28]
.word 0 # limit 0xFFFFF
.word 0 # base 0
.byte 0
.byte 0 # present, ring 0, data, expand-up, writable
.byte 0 # page-granular, 32-bit
.byte 0
#
# system data segment descriptor
#
.equ SYS_DATA64_SEL, .-_GDT_BASE # Selector [0x30]
.word 0xFFFF # limit 0xFFFFF
.word 0 # base 0
.byte 0
.byte 0x92 # P | DPL [1..2] | 1 | 1 | C | R | A
.byte 0xCF # G | D | L | AVL | Segment [19..16]
.byte 0
#
# system code segment descriptor
#
.equ SYS_CODE64_SEL, .-_GDT_BASE # Selector [0x38]
.word 0xFFFF # limit 0xFFFFF
.word 0 # base 0
.byte 0
.byte 0x9A # P | DPL [1..2] | 1 | 1 | C | R | A
.byte 0xAF # G | D | L | AVL | Segment [19..16]
.byte 0
# spare segment descriptor
.equ SPARE4_SEL, .-_GDT_BASE # Selector [0x40]
.word 0 # limit 0xFFFFF
.word 0 # base 0
.byte 0
.byte 0 # present, ring 0, data, expand-up, writable
.byte 0 # page-granular, 32-bit
.byte 0
_GDT_END:
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