diff options
author | Thomas Gleixner <tglx@linutronix.de> | 2007-10-11 11:15:17 +0200 |
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committer | Thomas Gleixner <tglx@linutronix.de> | 2007-10-11 11:15:17 +0200 |
commit | 977d5654cb630d6845b84a984fb5698e839f20f2 (patch) | |
tree | f5cfd7c4f4c72b97765a76298722b037e5d89418 /arch/x86_64/kernel/head.S | |
parent | 13c4896799d1610956f307534aa22d644b92bee7 (diff) |
x86_64: prepare shared kernel/head.S
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86_64/kernel/head.S')
-rw-r--r-- | arch/x86_64/kernel/head.S | 416 |
1 files changed, 0 insertions, 416 deletions
diff --git a/arch/x86_64/kernel/head.S b/arch/x86_64/kernel/head.S deleted file mode 100644 index b6167fe3330..00000000000 --- a/arch/x86_64/kernel/head.S +++ /dev/null @@ -1,416 +0,0 @@ -/* - * linux/arch/x86_64/kernel/head.S -- start in 32bit and switch to 64bit - * - * Copyright (C) 2000 Andrea Arcangeli <andrea@suse.de> SuSE - * Copyright (C) 2000 Pavel Machek <pavel@suse.cz> - * Copyright (C) 2000 Karsten Keil <kkeil@suse.de> - * Copyright (C) 2001,2002 Andi Kleen <ak@suse.de> - * Copyright (C) 2005 Eric Biederman <ebiederm@xmission.com> - */ - - -#include <linux/linkage.h> -#include <linux/threads.h> -#include <linux/init.h> -#include <asm/desc.h> -#include <asm/segment.h> -#include <asm/pgtable.h> -#include <asm/page.h> -#include <asm/msr.h> -#include <asm/cache.h> - -/* we are not able to switch in one step to the final KERNEL ADRESS SPACE - * because we need identity-mapped pages. - * - */ - - .text - .section .text.head - .code64 - .globl startup_64 -startup_64: - - /* - * At this point the CPU runs in 64bit mode CS.L = 1 CS.D = 1, - * and someone has loaded an identity mapped page table - * for us. These identity mapped page tables map all of the - * kernel pages and possibly all of memory. - * - * %esi holds a physical pointer to real_mode_data. - * - * We come here either directly from a 64bit bootloader, or from - * arch/x86_64/boot/compressed/head.S. - * - * We only come here initially at boot nothing else comes here. - * - * Since we may be loaded at an address different from what we were - * compiled to run at we first fixup the physical addresses in our page - * tables and then reload them. - */ - - /* Compute the delta between the address I am compiled to run at and the - * address I am actually running at. - */ - leaq _text(%rip), %rbp - subq $_text - __START_KERNEL_map, %rbp - - /* Is the address not 2M aligned? */ - movq %rbp, %rax - andl $~LARGE_PAGE_MASK, %eax - testl %eax, %eax - jnz bad_address - - /* Is the address too large? */ - leaq _text(%rip), %rdx - movq $PGDIR_SIZE, %rax - cmpq %rax, %rdx - jae bad_address - - /* Fixup the physical addresses in the page table - */ - addq %rbp, init_level4_pgt + 0(%rip) - addq %rbp, init_level4_pgt + (258*8)(%rip) - addq %rbp, init_level4_pgt + (511*8)(%rip) - - addq %rbp, level3_ident_pgt + 0(%rip) - - addq %rbp, level3_kernel_pgt + (510*8)(%rip) - addq %rbp, level3_kernel_pgt + (511*8)(%rip) - - addq %rbp, level2_fixmap_pgt + (506*8)(%rip) - - /* Add an Identity mapping if I am above 1G */ - leaq _text(%rip), %rdi - andq $LARGE_PAGE_MASK, %rdi - - movq %rdi, %rax - shrq $PUD_SHIFT, %rax - andq $(PTRS_PER_PUD - 1), %rax - jz ident_complete - - leaq (level2_spare_pgt - __START_KERNEL_map + _KERNPG_TABLE)(%rbp), %rdx - leaq level3_ident_pgt(%rip), %rbx - movq %rdx, 0(%rbx, %rax, 8) - - movq %rdi, %rax - shrq $PMD_SHIFT, %rax - andq $(PTRS_PER_PMD - 1), %rax - leaq __PAGE_KERNEL_LARGE_EXEC(%rdi), %rdx - leaq level2_spare_pgt(%rip), %rbx - movq %rdx, 0(%rbx, %rax, 8) -ident_complete: - - /* Fixup the kernel text+data virtual addresses - */ - leaq level2_kernel_pgt(%rip), %rdi - leaq 4096(%rdi), %r8 - /* See if it is a valid page table entry */ -1: testq $1, 0(%rdi) - jz 2f - addq %rbp, 0(%rdi) - /* Go to the next page */ -2: addq $8, %rdi - cmp %r8, %rdi - jne 1b - - /* Fixup phys_base */ - addq %rbp, phys_base(%rip) - -#ifdef CONFIG_SMP - addq %rbp, trampoline_level4_pgt + 0(%rip) - addq %rbp, trampoline_level4_pgt + (511*8)(%rip) -#endif -#ifdef CONFIG_ACPI_SLEEP - addq %rbp, wakeup_level4_pgt + 0(%rip) - addq %rbp, wakeup_level4_pgt + (511*8)(%rip) -#endif - - /* Due to ENTRY(), sometimes the empty space gets filled with - * zeros. Better take a jmp than relying on empty space being - * filled with 0x90 (nop) - */ - jmp secondary_startup_64 -ENTRY(secondary_startup_64) - /* - * At this point the CPU runs in 64bit mode CS.L = 1 CS.D = 1, - * and someone has loaded a mapped page table. - * - * %esi holds a physical pointer to real_mode_data. - * - * We come here either from startup_64 (using physical addresses) - * or from trampoline.S (using virtual addresses). - * - * Using virtual addresses from trampoline.S removes the need - * to have any identity mapped pages in the kernel page table - * after the boot processor executes this code. - */ - - /* Enable PAE mode and PGE */ - xorq %rax, %rax - btsq $5, %rax - btsq $7, %rax - movq %rax, %cr4 - - /* Setup early boot stage 4 level pagetables. */ - movq $(init_level4_pgt - __START_KERNEL_map), %rax - addq phys_base(%rip), %rax - movq %rax, %cr3 - - /* Ensure I am executing from virtual addresses */ - movq $1f, %rax - jmp *%rax -1: - - /* Check if nx is implemented */ - movl $0x80000001, %eax - cpuid - movl %edx,%edi - - /* Setup EFER (Extended Feature Enable Register) */ - movl $MSR_EFER, %ecx - rdmsr - btsl $_EFER_SCE, %eax /* Enable System Call */ - btl $20,%edi /* No Execute supported? */ - jnc 1f - btsl $_EFER_NX, %eax -1: wrmsr /* Make changes effective */ - - /* Setup cr0 */ -#define CR0_PM 1 /* protected mode */ -#define CR0_MP (1<<1) -#define CR0_ET (1<<4) -#define CR0_NE (1<<5) -#define CR0_WP (1<<16) -#define CR0_AM (1<<18) -#define CR0_PAGING (1<<31) - movl $CR0_PM|CR0_MP|CR0_ET|CR0_NE|CR0_WP|CR0_AM|CR0_PAGING,%eax - /* Make changes effective */ - movq %rax, %cr0 - - /* Setup a boot time stack */ - movq init_rsp(%rip),%rsp - - /* zero EFLAGS after setting rsp */ - pushq $0 - popfq - - /* - * We must switch to a new descriptor in kernel space for the GDT - * because soon the kernel won't have access anymore to the userspace - * addresses where we're currently running on. We have to do that here - * because in 32bit we couldn't load a 64bit linear address. - */ - lgdt cpu_gdt_descr(%rip) - - /* set up data segments. actually 0 would do too */ - movl $__KERNEL_DS,%eax - movl %eax,%ds - movl %eax,%ss - movl %eax,%es - - /* - * We don't really need to load %fs or %gs, but load them anyway - * to kill any stale realmode selectors. This allows execution - * under VT hardware. - */ - movl %eax,%fs - movl %eax,%gs - - /* - * Setup up a dummy PDA. this is just for some early bootup code - * that does in_interrupt() - */ - movl $MSR_GS_BASE,%ecx - movq $empty_zero_page,%rax - movq %rax,%rdx - shrq $32,%rdx - wrmsr - - /* esi is pointer to real mode structure with interesting info. - pass it to C */ - movl %esi, %edi - - /* Finally jump to run C code and to be on real kernel address - * Since we are running on identity-mapped space we have to jump - * to the full 64bit address, this is only possible as indirect - * jump. In addition we need to ensure %cs is set so we make this - * a far return. - */ - movq initial_code(%rip),%rax - pushq $0 # fake return address to stop unwinder - pushq $__KERNEL_CS # set correct cs - pushq %rax # target address in negative space - lretq - - /* SMP bootup changes these two */ -#ifndef CONFIG_HOTPLUG_CPU - .pushsection .init.data -#endif - .align 8 - .globl initial_code -initial_code: - .quad x86_64_start_kernel -#ifndef CONFIG_HOTPLUG_CPU - .popsection -#endif - .globl init_rsp -init_rsp: - .quad init_thread_union+THREAD_SIZE-8 - -bad_address: - jmp bad_address - -ENTRY(early_idt_handler) - cmpl $2,early_recursion_flag(%rip) - jz 1f - incl early_recursion_flag(%rip) - xorl %eax,%eax - movq 8(%rsp),%rsi # get rip - movq (%rsp),%rdx - movq %cr2,%rcx - leaq early_idt_msg(%rip),%rdi - call early_printk - cmpl $2,early_recursion_flag(%rip) - jz 1f - call dump_stack -#ifdef CONFIG_KALLSYMS - leaq early_idt_ripmsg(%rip),%rdi - movq 8(%rsp),%rsi # get rip again - call __print_symbol -#endif -1: hlt - jmp 1b -early_recursion_flag: - .long 0 - -early_idt_msg: - .asciz "PANIC: early exception rip %lx error %lx cr2 %lx\n" -early_idt_ripmsg: - .asciz "RIP %s\n" - -.balign PAGE_SIZE - -#define NEXT_PAGE(name) \ - .balign PAGE_SIZE; \ -ENTRY(name) - -/* Automate the creation of 1 to 1 mapping pmd entries */ -#define PMDS(START, PERM, COUNT) \ - i = 0 ; \ - .rept (COUNT) ; \ - .quad (START) + (i << 21) + (PERM) ; \ - i = i + 1 ; \ - .endr - - /* - * This default setting generates an ident mapping at address 0x100000 - * and a mapping for the kernel that precisely maps virtual address - * 0xffffffff80000000 to physical address 0x000000. (always using - * 2Mbyte large pages provided by PAE mode) - */ -NEXT_PAGE(init_level4_pgt) - .quad level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE - .fill 257,8,0 - .quad level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE - .fill 252,8,0 - /* (2^48-(2*1024*1024*1024))/(2^39) = 511 */ - .quad level3_kernel_pgt - __START_KERNEL_map + _PAGE_TABLE - -NEXT_PAGE(level3_ident_pgt) - .quad level2_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE - .fill 511,8,0 - -NEXT_PAGE(level3_kernel_pgt) - .fill 510,8,0 - /* (2^48-(2*1024*1024*1024)-((2^39)*511))/(2^30) = 510 */ - .quad level2_kernel_pgt - __START_KERNEL_map + _KERNPG_TABLE - .quad level2_fixmap_pgt - __START_KERNEL_map + _PAGE_TABLE - -NEXT_PAGE(level2_fixmap_pgt) - .fill 506,8,0 - .quad level1_fixmap_pgt - __START_KERNEL_map + _PAGE_TABLE - /* 8MB reserved for vsyscalls + a 2MB hole = 4 + 1 entries */ - .fill 5,8,0 - -NEXT_PAGE(level1_fixmap_pgt) - .fill 512,8,0 - -NEXT_PAGE(level2_ident_pgt) - /* Since I easily can, map the first 1G. - * Don't set NX because code runs from these pages. - */ - PMDS(0x0000000000000000, __PAGE_KERNEL_LARGE_EXEC, PTRS_PER_PMD) - -NEXT_PAGE(level2_kernel_pgt) - /* 40MB kernel mapping. The kernel code cannot be bigger than that. - When you change this change KERNEL_TEXT_SIZE in page.h too. */ - /* (2^48-(2*1024*1024*1024)-((2^39)*511)-((2^30)*510)) = 0 */ - PMDS(0x0000000000000000, __PAGE_KERNEL_LARGE_EXEC|_PAGE_GLOBAL, KERNEL_TEXT_SIZE/PMD_SIZE) - /* Module mapping starts here */ - .fill (PTRS_PER_PMD - (KERNEL_TEXT_SIZE/PMD_SIZE)),8,0 - -NEXT_PAGE(level2_spare_pgt) - .fill 512,8,0 - -#undef PMDS -#undef NEXT_PAGE - - .data - .align 16 - .globl cpu_gdt_descr -cpu_gdt_descr: - .word gdt_end-cpu_gdt_table-1 -gdt: - .quad cpu_gdt_table -#ifdef CONFIG_SMP - .rept NR_CPUS-1 - .word 0 - .quad 0 - .endr -#endif - -ENTRY(phys_base) - /* This must match the first entry in level2_kernel_pgt */ - .quad 0x0000000000000000 - -/* We need valid kernel segments for data and code in long mode too - * IRET will check the segment types kkeil 2000/10/28 - * Also sysret mandates a special GDT layout - */ - - .section .data.page_aligned, "aw" - .align PAGE_SIZE - -/* The TLS descriptors are currently at a different place compared to i386. - Hopefully nobody expects them at a fixed place (Wine?) */ - -ENTRY(cpu_gdt_table) - .quad 0x0000000000000000 /* NULL descriptor */ - .quad 0x00cf9b000000ffff /* __KERNEL32_CS */ - .quad 0x00af9b000000ffff /* __KERNEL_CS */ - .quad 0x00cf93000000ffff /* __KERNEL_DS */ - .quad 0x00cffb000000ffff /* __USER32_CS */ - .quad 0x00cff3000000ffff /* __USER_DS, __USER32_DS */ - .quad 0x00affb000000ffff /* __USER_CS */ - .quad 0x0 /* unused */ - .quad 0,0 /* TSS */ - .quad 0,0 /* LDT */ - .quad 0,0,0 /* three TLS descriptors */ - .quad 0x0000f40000000000 /* node/CPU stored in limit */ -gdt_end: - /* asm/segment.h:GDT_ENTRIES must match this */ - /* This should be a multiple of the cache line size */ - /* GDTs of other CPUs are now dynamically allocated */ - - /* zero the remaining page */ - .fill PAGE_SIZE / 8 - GDT_ENTRIES,8,0 - - .section .bss, "aw", @nobits - .align L1_CACHE_BYTES -ENTRY(idt_table) - .skip 256 * 16 - - .section .bss.page_aligned, "aw", @nobits - .align PAGE_SIZE -ENTRY(empty_zero_page) - .skip PAGE_SIZE |