diff options
Diffstat (limited to 'arch/x86/kernel/head_32.S')
| -rw-r--r-- | arch/x86/kernel/head_32.S | 151 |
1 files changed, 116 insertions, 35 deletions
diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S index 5d8c573..74ef4a4 100644 --- a/arch/x86/kernel/head_32.S +++ b/arch/x86/kernel/head_32.S @@ -19,6 +19,10 @@ #include <asm/thread_info.h> #include <asm/asm-offsets.h> #include <asm/setup.h> +#include <asm/processor-flags.h> + +/* Physical address */ +#define pa(X) ((X) - __PAGE_OFFSET) /* * References to members of the new_cpu_data structure. @@ -80,10 +84,6 @@ INIT_MAP_BEYOND_END = BOOTBITMAP_SIZE + (PAGE_TABLE_SIZE + ALLOCATOR_SLOP)*PAGE_ */ .section .text.head,"ax",@progbits ENTRY(startup_32) - /* check to see if KEEP_SEGMENTS flag is meaningful */ - cmpw $0x207, BP_version(%esi) - jb 1f - /* test KEEP_SEGMENTS flag to see if the bootloader is asking us to not reload segments */ testb $(1<<6), BP_loadflags(%esi) @@ -92,7 +92,7 @@ ENTRY(startup_32) /* * Set segments to known values. */ -1: lgdt boot_gdt_descr - __PAGE_OFFSET + lgdt pa(boot_gdt_descr) movl $(__BOOT_DS),%eax movl %eax,%ds movl %eax,%es @@ -105,8 +105,8 @@ ENTRY(startup_32) */ cld xorl %eax,%eax - movl $__bss_start - __PAGE_OFFSET,%edi - movl $__bss_stop - __PAGE_OFFSET,%ecx + movl $pa(__bss_start),%edi + movl $pa(__bss_stop),%ecx subl %edi,%ecx shrl $2,%ecx rep ; stosl @@ -118,31 +118,32 @@ ENTRY(startup_32) * (kexec on panic case). Hence copy out the parameters before initializing * page tables. */ - movl $(boot_params - __PAGE_OFFSET),%edi + movl $pa(boot_params),%edi movl $(PARAM_SIZE/4),%ecx cld rep movsl - movl boot_params - __PAGE_OFFSET + NEW_CL_POINTER,%esi + movl pa(boot_params) + NEW_CL_POINTER,%esi andl %esi,%esi jz 1f # No comand line - movl $(boot_command_line - __PAGE_OFFSET),%edi + movl $pa(boot_command_line),%edi movl $(COMMAND_LINE_SIZE/4),%ecx rep movsl 1: #ifdef CONFIG_PARAVIRT - cmpw $0x207, (boot_params + BP_version - __PAGE_OFFSET) + /* This is can only trip for a broken bootloader... */ + cmpw $0x207, pa(boot_params + BP_version) jb default_entry /* Paravirt-compatible boot parameters. Look to see what architecture we're booting under. */ - movl (boot_params + BP_hardware_subarch - __PAGE_OFFSET), %eax + movl pa(boot_params + BP_hardware_subarch), %eax cmpl $num_subarch_entries, %eax jae bad_subarch - movl subarch_entries - __PAGE_OFFSET(,%eax,4), %eax + movl pa(subarch_entries)(,%eax,4), %eax subl $__PAGE_OFFSET, %eax jmp *%eax @@ -170,17 +171,68 @@ num_subarch_entries = (. - subarch_entries) / 4 * Mappings are created both at virtual address 0 (identity mapping) * and PAGE_OFFSET for up to _end+sizeof(page tables)+INIT_MAP_BEYOND_END. * - * Warning: don't use %esi or the stack in this code. However, %esp - * can be used as a GPR if you really need it... + * Note that the stack is not yet set up! */ -page_pde_offset = (__PAGE_OFFSET >> 20); +#define PTE_ATTR 0x007 /* PRESENT+RW+USER */ +#define PDE_ATTR 0x067 /* PRESENT+RW+USER+DIRTY+ACCESSED */ +#define PGD_ATTR 0x001 /* PRESENT (no other attributes) */ default_entry: - movl $(pg0 - __PAGE_OFFSET), %edi - movl $(swapper_pg_dir - __PAGE_OFFSET), %edx - movl $0x007, %eax /* 0x007 = PRESENT+RW+USER */ +#ifdef CONFIG_X86_PAE + + /* + * In PAE mode swapper_pg_dir is statically defined to contain enough + * entries to cover the VMSPLIT option (that is the top 1, 2 or 3 + * entries). The identity mapping is handled by pointing two PGD + * entries to the first kernel PMD. + * + * Note the upper half of each PMD or PTE are always zero at + * this stage. + */ + +#define KPMDS ((0x100000000-__PAGE_OFFSET) >> 30) /* Number of kernel PMDs */ + + xorl %ebx,%ebx /* %ebx is kept at zero */ + + movl $pa(pg0), %edi + movl $pa(swapper_pg_pmd), %edx + movl $PTE_ATTR, %eax +10: + leal PDE_ATTR(%edi),%ecx /* Create PMD entry */ + movl %ecx,(%edx) /* Store PMD entry */ + /* Upper half already zero */ + addl $8,%edx + movl $512,%ecx +11: + stosl + xchgl %eax,%ebx + stosl + xchgl %eax,%ebx + addl $0x1000,%eax + loop 11b + + /* + * End condition: we must map up to and including INIT_MAP_BEYOND_END + * bytes beyond the end of our own page tables. + */ + leal (INIT_MAP_BEYOND_END+PTE_ATTR)(%edi),%ebp + cmpl %ebp,%eax + jb 10b +1: + movl %edi,pa(init_pg_tables_end) + + /* Do early initialization of the fixmap area */ + movl $pa(swapper_pg_fixmap)+PDE_ATTR,%eax + movl %eax,pa(swapper_pg_pmd+0x1000*KPMDS-8) +#else /* Not PAE */ + +page_pde_offset = (__PAGE_OFFSET >> 20); + + movl $pa(pg0), %edi + movl $pa(swapper_pg_dir), %edx + movl $PTE_ATTR, %eax 10: - leal 0x007(%edi),%ecx /* Create PDE entry */ + leal PDE_ATTR(%edi),%ecx /* Create PDE entry */ movl %ecx,(%edx) /* Store identity PDE entry */ movl %ecx,page_pde_offset(%edx) /* Store kernel PDE entry */ addl $4,%edx @@ -189,19 +241,20 @@ default_entry: stosl addl $0x1000,%eax loop 11b - /* End condition: we must map up to and including INIT_MAP_BEYOND_END */ - /* bytes beyond the end of our own page tables; the +0x007 is the attribute bits */ - leal (INIT_MAP_BEYOND_END+0x007)(%edi),%ebp + /* + * End condition: we must map up to and including INIT_MAP_BEYOND_END + * bytes beyond the end of our own page tables; the +0x007 is + * the attribute bits + */ + leal (INIT_MAP_BEYOND_END+PTE_ATTR)(%edi),%ebp cmpl %ebp,%eax jb 10b - movl %edi,(init_pg_tables_end - __PAGE_OFFSET) - - /* Do an early initialization of the fixmap area */ - movl $(swapper_pg_dir - __PAGE_OFFSET), %edx - movl $(swapper_pg_pmd - __PAGE_OFFSET), %eax - addl $0x67, %eax /* 0x67 == _PAGE_TABLE */ - movl %eax, 4092(%edx) + movl %edi,pa(init_pg_tables_end) + /* Do early initialization of the fixmap area */ + movl $pa(swapper_pg_fixmap)+PDE_ATTR,%eax + movl %eax,pa(swapper_pg_dir+0xffc) +#endif jmp 3f /* * Non-boot CPU entry point; entered from trampoline.S @@ -241,7 +294,7 @@ ENTRY(startup_32_smp) * NOTE! We have to correct for the fact that we're * not yet offset PAGE_OFFSET.. */ -#define cr4_bits mmu_cr4_features-__PAGE_OFFSET +#define cr4_bits pa(mmu_cr4_features) movl cr4_bits,%edx andl %edx,%edx jz 6f @@ -276,10 +329,10 @@ ENTRY(startup_32_smp) /* * Enable paging */ - movl $swapper_pg_dir-__PAGE_OFFSET,%eax + movl $pa(swapper_pg_dir),%eax movl %eax,%cr3 /* set the page table pointer.. */ movl %cr0,%eax - orl $0x80000000,%eax + orl $X86_CR0_PG,%eax movl %eax,%cr0 /* ..and set paging (PG) bit */ ljmp $__BOOT_CS,$1f /* Clear prefetch and normalize %eip */ 1: @@ -552,16 +605,44 @@ ENTRY(_stext) */ .section ".bss.page_aligned","wa" .align PAGE_SIZE_asm +#ifdef CONFIG_X86_PAE +ENTRY(swapper_pg_pmd) + .fill 1024*KPMDS,4,0 +#else ENTRY(swapper_pg_dir) .fill 1024,4,0 -ENTRY(swapper_pg_pmd) +#endif +ENTRY(swapper_pg_fixmap) .fill 1024,4,0 ENTRY(empty_zero_page) .fill 4096,1,0 - /* * This starts the data section. */ +#ifdef CONFIG_X86_PAE +.section ".data.page_aligned","wa" + /* Page-aligned for the benefit of paravirt? */ + .align PAGE_SIZE_asm +ENTRY(swapper_pg_dir) + .long pa(swapper_pg_pmd+PGD_ATTR),0 /* low identity map */ +# if KPMDS == 3 + .long pa(swapper_pg_pmd+PGD_ATTR),0 + .long pa(swapper_pg_pmd+PGD_ATTR+0x1000),0 + .long pa(swapper_pg_pmd+PGD_ATTR+0x2000),0 +# elif KPMDS == 2 + .long 0,0 + .long pa(swapper_pg_pmd+PGD_ATTR),0 + .long pa(swapper_pg_pmd+PGD_ATTR+0x1000),0 +# elif KPMDS == 1 + .long 0,0 + .long 0,0 + .long pa(swapper_pg_pmd+PGD_ATTR),0 +# else +# error "Kernel PMDs should be 1, 2 or 3" +# endif + .align PAGE_SIZE_asm /* needs to be page-sized too */ +#endif + .data ENTRY(stack_start) .long init_thread_union+THREAD_SIZE |
