source: mainline/kernel/arch/amd64/src/boot/boot.S@ 0f94c3d

#
# Copyright (c) 2005 Ondrej Palkovsky
# Copyright (c) 2006 Martin Decky
# Copyright (c) 2008 Jakub Jermar
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
#
# - Redistributions of source code must retain the above copyright
#   notice, this list of conditions and the following disclaimer.
# - Redistributions in binary form must reproduce the above copyright
#   notice, this list of conditions and the following disclaimer in the
#   documentation and/or other materials provided with the distribution.
# - The name of the author may not be used to endorse or promote products
#   derived from this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
# OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
# IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
# NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
# THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#

#include <arch/boot/boot.h>
#include <arch/boot/memmap.h>
#include <arch/mm/page.h>       
#include <arch/mm/ptl.h>
#include <arch/pm.h>
#include <arch/cpu.h>
#include <arch/cpuid.h>

#define START_STACK     (BOOT_OFFSET - BOOT_STACK_SIZE)
        
.section K_TEXT_START, "ax"

.code32
.align 4
.global multiboot_image_start
multiboot_header:
        .long MULTIBOOT_HEADER_MAGIC
        .long MULTIBOOT_HEADER_FLAGS
        .long -(MULTIBOOT_HEADER_MAGIC + MULTIBOOT_HEADER_FLAGS)        # checksum
        .long multiboot_header
        .long unmapped_ktext_start
        .long 0
        .long 0
        .long multiboot_image_start

multiboot_image_start:
        cld
        movl $START_STACK, %esp                 # initialize stack pointer
        lgdtl bootstrap_gdtr                    # initialize Global Descriptor Table register

        movw $gdtselector(KDATA_DES), %cx
        movw %cx, %es
        movw %cx, %ds                                                   # kernel data + stack
        movw %cx, %ss
        # Simics seems to remove hidden part of GS on entering user mode
        #  when _visible_ part of GS does not point to user-mode segment
        movw $gdtselector(UDATA_DES), %cx
        movw %cx, %fs
        movw %cx, %gs
        
        jmpl $gdtselector(KTEXT32_DES), $multiboot_meeting_point
        multiboot_meeting_point:
        
        movl %eax, grub_eax                                             # save parameters from GRUB
        movl %ebx, grub_ebx
        
        # Protected 32-bit. We want to reuse the code-seg descriptor,
        # the Default operand size must not be 1 when entering long mode
        
        movl $(INTEL_CPUID_EXTENDED), %eax  
        cpuid
        cmp $(INTEL_CPUID_EXTENDED), %eax
        ja extended_cpuid_supported
                
                movl $extended_cpuid_msg, %esi
                jmp error_halt
        
        extended_cpuid_supported:
        
        movl $(AMD_CPUID_EXTENDED), %eax
        cpuid
        bt $(AMD_EXT_LONG_MODE), %edx
        jc long_mode_supported
                
                movl $long_mode_msg, %esi
                jmp error_halt

        long_mode_supported:
        
        bt $(AMD_EXT_NOEXECUTE), %edx
        jc noexecute_supported
        
                movl $noexecute_msg, %esi
                jmp error_halt
        
        noexecute_supported:
        
        movl $(INTEL_CPUID_STANDARD), %eax
        cpuid
        bt $(INTEL_FXSAVE), %edx
        jc fx_supported
        
                movl $fx_msg, %esi
                jmp error_halt
        
        fx_supported:
        
        bt $(INTEL_SSE2), %edx
        jc sse2_supported
        
                movl $sse2_msg, %esi
                jmp error_halt
        
        sse2_supported:
        
#ifdef CONFIG_FB
        mov $vesa_init, %esi
        mov $VESA_INIT_SEGMENT << 4, %edi
        mov $e_vesa_init - vesa_init, %ecx
        rep movsb

        mov $VESA_INIT_SEGMENT << 4, %edi
        jmpl *%edi
        
        vesa_meeting_point:
        
        mov %esi, KA2PA(vesa_ph_addr)
        mov %di, KA2PA(vesa_height)
        shr $16, %edi
        mov %di, KA2PA(vesa_width)
        mov %bx, KA2PA(vesa_scanline)
        shr $16, %ebx
        mov %bx, KA2PA(vesa_bpp)
#endif  
        
        # Enable 64-bit page translation entries - CR4.PAE = 1.
        # Paging is not enabled until after long mode is enabled
        
        movl %cr4, %eax
        btsl $5, %eax
        movl %eax, %cr4

        # Set up paging tables
        
        leal ptl_0, %eax
        movl %eax, %cr3
        
        # Enable long mode
        
        movl $EFER_MSR_NUM, %ecx                        # EFER MSR number
        rdmsr                                           # Read EFER
        btsl $AMD_LME_FLAG, %eax                        # Set LME = 1
        wrmsr                                           # Write EFER
        
        # Enable paging to activate long mode (set CR0.PG = 1)
        
        movl %cr0, %eax
        btsl $31, %eax
        movl %eax, %cr0
        
        # At this point we are in compatibility mode
        
        jmpl $gdtselector(KTEXT_DES), $start64

.code64
start64:
        movq $(PA2KA(START_STACK)), %rsp
        movl grub_eax, %eax
        movl grub_ebx, %ebx
        
        cmpl $MULTIBOOT_LOADER_MAGIC, %eax                      # compare GRUB signature
        je valid_boot
                
                xorl %ecx, %ecx                                 # no memory size or map available
                movl %ecx, e820counter
                
                jmp invalid_boot
                
        valid_boot:
                
                movl (%ebx), %eax                               # ebx = physical address of struct multiboot_info
                
                bt $3, %eax                                     # mbi->flags[3] (mods_count, mods_addr valid)
                jc mods_valid
                        
                        xorq %rcx, %rcx
                        movq %rcx, init
                        jmp mods_end
                
                mods_valid:
                
                xorq %rcx, %rcx
                movl 20(%ebx), %ecx                             # mbi->mods_count
                movq %rcx, init
                
                cmpl $0, %ecx
                je mods_end
                
                movl 24(%ebx), %esi                             # mbi->mods_addr
                movq $init, %rdi
                
                mods_loop:
                        
                        xorq %rdx, %rdx
                        movl 0(%esi), %edx                      # mods->mod_start
                        movq $0xffff800000000000, %r10
                        addq %r10, %rdx
                        movq %rdx, 8(%rdi)
                        
                        xorq %rdx, %rdx
                        movl 4(%esi), %edx
                        subl 0(%esi), %edx                      # mods->mod_end - mods->mod_start
                        movq %rdx, 16(%rdi)
                        
                        addl $16, %esi
                        addq $48, %rdi
                        
                        loop mods_loop
                        
                mods_end:
                
                bt $6, %eax                                     # mbi->flags[6] (mmap_length, mmap_addr valid)  
                jc mmap_valid
                        
                        xorl %edx, %edx
                        jmp mmap_invalid
                        
                mmap_valid:
                movl 44(%ebx), %ecx                             # mbi->mmap_length
                movl 48(%ebx), %esi                             # mbi->mmap_addr
                movq $e820table, %rdi
                xorl %edx, %edx
                
                mmap_loop:
                        cmpl $0, %ecx
                        jle mmap_end
                        
                        movl 4(%esi), %eax                      # mmap->base_addr_low
                        movl %eax, (%rdi)
                        
                        movl 8(%esi), %eax                      # mmap->base_addr_high
                        movl %eax, 4(%rdi)
                        
                        movl 12(%esi), %eax                     # mmap->length_low
                        movl %eax, 8(%rdi)
                        
                        movl 16(%esi), %eax                     # mmap->length_high
                        movl %eax, 12(%rdi)
                        
                        movl 20(%esi), %eax                     # mmap->type
                        movl %eax, 16(%rdi)
                        
                        movl (%esi), %eax                       # mmap->size
                        addl $0x4, %eax
                        addl %eax, %esi
                        subl %eax, %ecx
                        addq $MEMMAP_E820_RECORD_SIZE, %rdi
                        incl %edx
                        jmp mmap_loop
                
                mmap_end:
                
                mmap_invalid:
                movl %edx, e820counter
                
        invalid_boot:
        
#ifdef CONFIG_SMP
        
        # copy AP bootstrap routines below 1 MB
        
        movq $BOOT_OFFSET, %rsi
        movq $AP_BOOT_OFFSET, %rdi
        movq $_hardcoded_unmapped_size, %rcx
        rep movsb
        
#endif
        
        call main_bsp   # never returns
        
        cli
        hlt

#ifdef CONFIG_FB
.code32
vesa_init:
        jmp $gdtselector(VESA_INIT_DES), $vesa_init_real - vesa_init
        
.code16
vesa_init_real:
        
        mov %cr0, %eax
        and $~1, %eax
        mov %eax, %cr0
        
        jmp $VESA_INIT_SEGMENT, $vesa_init_real2 - vesa_init
        
vesa_init_real2:
        
        mov $VESA_INIT_SEGMENT, %bx
        
        mov %bx, %es
        mov %bx, %fs
        mov %bx, %gs
        mov %bx, %ds
        mov %bx, %ss
        
        movl $0x0000fffc, %esp
        movl $0x0000fffc, %ebp
        
#define VESA_INFO_SIZE 1024

#define VESA_MODE_ATTRIBUTES_OFFSET 0
#define VESA_MODE_LIST_PTR_OFFSET 14
#define VESA_MODE_SCANLINE_OFFSET 16
#define VESA_MODE_WIDTH_OFFSET 18
#define VESA_MODE_HEIGHT_OFFSET 20
#define VESA_MODE_BPP_OFFSET 25
#define VESA_MODE_PHADDR_OFFSET 40

#define VESA_END_OF_MODES 0xffff

#define VESA_OK 0x4f

#define VESA_GET_INFO 0x4f00
#define VESA_GET_MODE_INFO 0x4f01
#define VESA_SET_MODE 0x4f02
#define VESA_SET_PALETTE 0x4f09

#define CONFIG_VESA_BPP_a 255

#if CONFIG_VESA_BPP == 24
#define CONFIG_VESA_BPP_VARIANT 32
#endif

        mov $VESA_GET_INFO, %ax
        mov $e_vesa_init - vesa_init, %di
        push %di
        int $0x10
        
        pop %di
        cmp $VESA_OK, %al
        jnz 0f
        
        mov 2 + VESA_MODE_LIST_PTR_OFFSET(%di), %si
        mov %si, %gs
        mov VESA_MODE_LIST_PTR_OFFSET(%di), %si
        
        add $VESA_INFO_SIZE, %di

1:# Try next mode
        mov %gs:(%si), %cx
        cmp $VESA_END_OF_MODES, %cx
        jz 0f
        
        inc %si
        inc %si
        push %cx
        push %di
        push %si
        mov $VESA_GET_MODE_INFO, %ax
        int $0x10
        
        pop %si
        pop %di
        pop %cx
        cmp $VESA_OK, %al
        jnz 0f
        
        mov $CONFIG_VESA_WIDTH, %ax
        cmp VESA_MODE_WIDTH_OFFSET(%di), %ax
        jnz 1b
        
        mov $CONFIG_VESA_HEIGHT, %ax
        cmp VESA_MODE_HEIGHT_OFFSET(%di), %ax
        jnz 1b
        
        mov $CONFIG_VESA_BPP, %al
        cmp VESA_MODE_BPP_OFFSET(%di), %al

#ifdef CONFIG_VESA_BPP_VARIANT
        jz 2f
        
        mov $CONFIG_VESA_BPP_VARIANT, %al
        cmp VESA_MODE_BPP_OFFSET(%di), %al
#endif
        jnz 1b
        
2:
        
        mov %cx, %bx
        or $0xc000, %bx
        push %di
        mov $VESA_SET_MODE, %ax
        int $0x10
        
        pop %di
        cmp $VESA_OK, %al
        jnz 0f

#if CONFIG_VESA_BPP == 8
        
        # Set 3:2:3 VGA palette
        
        mov VESA_MODE_ATTRIBUTES_OFFSET(%di), %ax
        push %di
        mov $vga323 - vesa_init, %di
        mov $0x100, %ecx
        
        bt $5, %ax                                              # Test if VGA compatible registers are present
        jnc vga_compat
                
                # Try VESA routine to set palette
                
                mov $VESA_SET_PALETTE, %ax
                xor %bl, %bl
                xor %dx, %dx
                int $0x10
                
                cmp $0x00, %ah
                je vga_not_compat
        
        vga_compat:
                
                # Try VGA registers to set palette
                
                movw $0x3c6, %dx                                # Set palette mask
                movb $0xff, %al
                outb %al, %dx
                
                movw $0x3c8, %dx                                # First index to set
                xor %al, %al
                outb %al, %dx
                
                movw $0x3c9, %dx                                # Data port
                vga_loop:
                        movb %es:2(%di), %al
                        outb %al, %dx
                        
                        movb %es:1(%di), %al
                        outb %al, %dx
                        
                        movb %es:(%di), %al
                        outb %al, %dx
                        
                        addw $4, %di
                        loop vga_loop
                
        vga_not_compat:
        
        pop %di
        
#endif
        
        mov VESA_MODE_PHADDR_OFFSET(%di), %esi
        mov VESA_MODE_WIDTH_OFFSET(%di), %ax
        shl $16, %eax
        mov VESA_MODE_HEIGHT_OFFSET(%di), %ax
        mov VESA_MODE_BPP_OFFSET(%di), %bl
        xor %bh, %bh
        shl $16, %ebx
        mov VESA_MODE_SCANLINE_OFFSET(%di), %bx
        mov %eax, %edi
        
8:
        
        mov %cr0, %eax
        or $1, %eax
        mov %eax, %cr0
        
        jmp 9f
9:
        
        ljmpl $gdtselector(KTEXT32_DES), $(vesa_init_protect - vesa_init + VESA_INIT_SEGMENT << 4)
        
0:# No prefered mode found
        mov $0x111, %cx
        push %di
        push %cx
        mov $VESA_GET_MODE_INFO, %ax
        int $0x10
        
        pop %cx
        pop %di
        cmp $VESA_OK, %al
        jnz 1f
        jz 2b                                           # Force relative jump

1:
        mov $0x0003, %ax
        int $0x10
        mov $0xffffffff, %edi                           # EGA text mode used, because of problems with VESA
        xor %ax, %ax
        jz 8b                                           # Force relative jump

vga323:
#include "vga323.pal"   
        
.code32
vesa_init_protect:
        movw $gdtselector(KDATA_DES), %cx
        movw %cx, %es
        movw %cx, %ds                                   # kernel data + stack
        movw %cx, %ss
        # Simics seems to remove hidden part of GS on entering user mode
        #  when _visible_ part of GS does not point to user-mode segment
        movw $gdtselector(UDATA_DES), %cx
        movw %cx, %fs
        movw %cx, %gs
        
        movl $START_STACK, %esp                         # initialize stack pointer
        
        jmpl $gdtselector(KTEXT32_DES), $vesa_meeting_point
        
.align 4
e_vesa_init:
#endif

# Print string from %esi to EGA display (in red) and halt
error_halt:
        movl $0xb8000, %edi                             # base of EGA text mode memory
        xorl %eax, %eax
        
        movw $0x3d4, %dx                                # read bits 8 - 15 of the cursor address
        movb $0xe, %al
        outb %al, %dx
        
        movw $0x3d5, %dx
        inb %dx, %al
        shl $8, %ax
        
        movw $0x3d4, %dx                                # read bits 0 - 7 of the cursor address
        movb $0xf, %al
        outb %al, %dx
        
        movw $0x3d5, %dx
        inb %dx, %al
        
        cmp $1920, %ax
        jbe cursor_ok
                movw $1920, %ax                         # sanity check for the cursor on the last line
        cursor_ok:
        
        movw %ax, %bx
        shl $1, %eax
        addl %eax, %edi
        
        movw $0x0c00, %ax                               # black background, light red foreground
        
        ploop:
                lodsb
                cmp $0, %al
                je ploop_end
                stosw
                inc %bx 
                jmp ploop
        ploop_end:
        
        movw $0x3d4, %dx                                # write bits 8 - 15 of the cursor address
        movb $0xe, %al
        outb %al, %dx
        
        movw $0x3d5, %dx
        movb %bh, %al
        outb %al, %dx
        
        movw $0x3d4, %dx                                # write bits 0 - 7 of the cursor address
        movb $0xf, %al
        outb %al, %dx
        
        movw $0x3d5, %dx
        movb %bl, %al
        outb %al, %dx
                
        cli
        hlt
                                

.section K_INI_PTLS, "aw", @progbits

#
# Macro for generating initial page table contents.
# @param cnt    Number of entries to generat. Must be multiple of 8.
# @param g      Number of GB that will be added to the mapping.
#
.macro ptl2gen cnt g 
.if \cnt
        ptl2gen "\cnt - 8" \g 
        .quad ((\cnt - 8) * 0x200000) + (\g * 1024 * 1024 * 1024) | (PTL_WRITABLE | PTL_PRESENT | PTL_2MB_PAGE)
        .quad ((\cnt - 7) * 0x200000) + (\g * 1024 * 1024 * 1024) | (PTL_WRITABLE | PTL_PRESENT | PTL_2MB_PAGE)
        .quad ((\cnt - 6) * 0x200000) + (\g * 1024 * 1024 * 1024) | (PTL_WRITABLE | PTL_PRESENT | PTL_2MB_PAGE)
        .quad ((\cnt - 5) * 0x200000) + (\g * 1024 * 1024 * 1024) | (PTL_WRITABLE | PTL_PRESENT | PTL_2MB_PAGE)
        .quad ((\cnt - 4) * 0x200000) + (\g * 1024 * 1024 * 1024) | (PTL_WRITABLE | PTL_PRESENT | PTL_2MB_PAGE)
        .quad ((\cnt - 3) * 0x200000) + (\g * 1024 * 1024 * 1024) | (PTL_WRITABLE | PTL_PRESENT | PTL_2MB_PAGE)
        .quad ((\cnt - 2) * 0x200000) + (\g * 1024 * 1024 * 1024) | (PTL_WRITABLE | PTL_PRESENT | PTL_2MB_PAGE)
        .quad ((\cnt - 1) * 0x200000) + (\g * 1024 * 1024 * 1024) | (PTL_WRITABLE | PTL_PRESENT | PTL_2MB_PAGE)
.endif
.endm

# Page table for pages in the first gigabyte.
.align 4096
.global ptl_2_0g
ptl_2_0g:       
        ptl2gen 512 0

# Page table for pages in the second gigabyte.
.align 4096
.global ptl_2_1g
ptl_2_1g:
        ptl2gen 512 1

# Page table for pages in the third gigabyte.
.align 4096
.global ptl_2_2g
ptl_2_2g:
        ptl2gen 512 2

# Page table for pages in the fourth gigabyte.
.align 4096
.global ptl_2_3g
ptl_2_3g:
        ptl2gen 512 3

.align 4096
.global ptl_1
ptl_1:
        # Identity mapping for [0; 4G)
        .quad ptl_2_0g + (PTL_WRITABLE | PTL_PRESENT)
        .quad ptl_2_1g + (PTL_WRITABLE | PTL_PRESENT) 
        .quad ptl_2_2g + (PTL_WRITABLE | PTL_PRESENT)
        .quad ptl_2_3g + (PTL_WRITABLE | PTL_PRESENT)
        .fill 506, 8, 0
        # Mapping of [0; 1G) at -2G
        .quad ptl_2_0g + (PTL_WRITABLE | PTL_PRESENT)
        .fill 1, 8, 0
        
.align 4096
.global ptl_0
ptl_0:
        .quad ptl_1 + (PTL_WRITABLE | PTL_PRESENT)
        .fill 255,8,0
        .quad ptl_1 + (PTL_WRITABLE | PTL_PRESENT)
        .fill 254,8,0
        .quad ptl_1 + (PTL_WRITABLE | PTL_PRESENT)

.section K_DATA_START, "aw", @progbits

.global bootstrap_gdtr
bootstrap_gdtr:
        .word gdtselector(GDT_ITEMS)
        .long KA2PA(gdt)

grub_eax:
        .long 0

grub_ebx:
        .long 0

extended_cpuid_msg:
        .asciz "Extended CPUID not supported. System halted."
long_mode_msg:
        .asciz "64 bit long mode not supported. System halted."
noexecute_msg:
        .asciz "No-execute pages not supported. System halted."
fx_msg:
        .asciz "FXSAVE/FXRESTORE instructions not supported. System halted."
sse2_msg:
        .asciz "SSE2 instructions not supported. System halted."