# # 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 #include #include #include #include #include #include #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: #include "vesa_prot.inc" # # 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 # call arch_pre_main(grub_eax, grub_ebx) xorq %rdi, %rdi movl grub_eax, %edi xorq %rsi, %rsi movl grub_ebx, %esi movabsq $arch_pre_main, %rax callq *%rax # create the first stack frame pushq $0 movq %rsp, %rbp movabsq $main_bsp, %rax call *%rax # not reached cli hlt0: hlt jmp hlt0 # 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 hlt1: hlt jmp hlt1 #include "vesa_real.inc" .section K_INI_PTLS, "aw", @progbits # # Macro for generating initial page table contents. # @param cnt Number of entries to generate. 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 508, 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 255, 8, 0 .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 "Error: Extended CPUID not supported -- CPU is not 64-bit. System halted." long_mode_msg: .asciz "Error: 64-bit long mode not supported. System halted." noexecute_msg: .asciz "Error: No-execute pages not supported. System halted." fx_msg: .asciz "Error: FXSAVE/FXRESTORE instructions not supported. System halted." sse2_msg: .asciz "Error: SSE2 instructions not supported. System halted."