diff options
author | Stephen Rothwell <sfr@canb.auug.org.au> | 2017-02-17 12:55:52 +1100 |
---|---|---|
committer | Stephen Rothwell <sfr@canb.auug.org.au> | 2017-02-17 12:55:56 +1100 |
commit | 2bf88e1cb7b556a34f750e3dff95b03e8ae83606 (patch) | |
tree | a4d1d02b35b33994322ad917a11e2527891ec1bd /arch/x86/kernel/head_32.S | |
parent | 4923ffc1ba3a1a8fe30418aff905194dee483c15 (diff) | |
parent | 1098ea741fc4168264185b6782135d029dce435c (diff) |
Merge remote-tracking branch 'tip/auto-latest'
Diffstat (limited to 'arch/x86/kernel/head_32.S')
-rw-r--r-- | arch/x86/kernel/head_32.S | 121 |
1 files changed, 7 insertions, 114 deletions
diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S index 4e8577d03372..1f85ee8f9439 100644 --- a/arch/x86/kernel/head_32.S +++ b/arch/x86/kernel/head_32.S @@ -24,6 +24,7 @@ #include <asm/nops.h> #include <asm/bootparam.h> #include <asm/export.h> +#include <asm/pgtable_32.h> /* Physical address */ #define pa(X) ((X) - __PAGE_OFFSET) @@ -41,44 +42,10 @@ #define X86_CAPABILITY new_cpu_data+CPUINFO_x86_capability #define X86_VENDOR_ID new_cpu_data+CPUINFO_x86_vendor_id -/* - * This is how much memory in addition to the memory covered up to - * and including _end we need mapped initially. - * We need: - * (KERNEL_IMAGE_SIZE/4096) / 1024 pages (worst case, non PAE) - * (KERNEL_IMAGE_SIZE/4096) / 512 + 4 pages (worst case for PAE) - * - * Modulo rounding, each megabyte assigned here requires a kilobyte of - * memory, which is currently unreclaimed. - * - * This should be a multiple of a page. - * - * KERNEL_IMAGE_SIZE should be greater than pa(_end) - * and small than max_low_pfn, otherwise will waste some page table entries - */ - -#if PTRS_PER_PMD > 1 -#define PAGE_TABLE_SIZE(pages) (((pages) / PTRS_PER_PMD) + PTRS_PER_PGD) -#else -#define PAGE_TABLE_SIZE(pages) ((pages) / PTRS_PER_PGD) -#endif #define SIZEOF_PTREGS 17*4 /* - * Number of possible pages in the lowmem region. - * - * We shift 2 by 31 instead of 1 by 32 to the left in order to avoid a - * gas warning about overflowing shift count when gas has been compiled - * with only a host target support using a 32-bit type for internal - * representation. - */ -LOWMEM_PAGES = (((2<<31) - __PAGE_OFFSET) >> PAGE_SHIFT) - -/* Enough space to fit pagetables for the low memory linear map */ -MAPPING_BEYOND_END = PAGE_TABLE_SIZE(LOWMEM_PAGES) << PAGE_SHIFT - -/* * Worst-case size of the kernel mapping we need to make: * a relocatable kernel can live anywhere in lowmem, so we need to be able * to map all of lowmem. @@ -160,90 +127,15 @@ ENTRY(startup_32) call load_ucode_bsp #endif -/* - * Initialize page tables. This creates a PDE and a set of page - * tables, which are located immediately beyond __brk_base. The variable - * _brk_end is set up to point to the first "safe" location. - * Mappings are created both at virtual address 0 (identity mapping) - * and PAGE_OFFSET for up to _end. - */ -#ifdef CONFIG_X86_PAE - - /* - * In PAE mode initial_page_table 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 (((-__PAGE_OFFSET) >> 30) & 3) /* Number of kernel PMDs */ - - xorl %ebx,%ebx /* %ebx is kept at zero */ - - movl $pa(__brk_base), %edi - movl $pa(initial_pg_pmd), %edx - movl $PTE_IDENT_ATTR, %eax -10: - leal PDE_IDENT_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 the end + MAPPING_BEYOND_END. - */ - movl $pa(_end) + MAPPING_BEYOND_END + PTE_IDENT_ATTR, %ebp - cmpl %ebp,%eax - jb 10b -1: - addl $__PAGE_OFFSET, %edi - movl %edi, pa(_brk_end) - shrl $12, %eax - movl %eax, pa(max_pfn_mapped) + /* Create early pagetables. */ + call mk_early_pgtbl_32 /* Do early initialization of the fixmap area */ movl $pa(initial_pg_fixmap)+PDE_IDENT_ATTR,%eax +#ifdef CONFIG_X86_PAE +#define KPMDS (((-__PAGE_OFFSET) >> 30) & 3) /* Number of kernel PMDs */ movl %eax,pa(initial_pg_pmd+0x1000*KPMDS-8) -#else /* Not PAE */ - -page_pde_offset = (__PAGE_OFFSET >> 20); - - movl $pa(__brk_base), %edi - movl $pa(initial_page_table), %edx - movl $PTE_IDENT_ATTR, %eax -10: - leal PDE_IDENT_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 - movl $1024, %ecx -11: - stosl - addl $0x1000,%eax - loop 11b - /* - * End condition: we must map up to the end + MAPPING_BEYOND_END. - */ - movl $pa(_end) + MAPPING_BEYOND_END + PTE_IDENT_ATTR, %ebp - cmpl %ebp,%eax - jb 10b - addl $__PAGE_OFFSET, %edi - movl %edi, pa(_brk_end) - shrl $12, %eax - movl %eax, pa(max_pfn_mapped) - - /* Do early initialization of the fixmap area */ - movl $pa(initial_pg_fixmap)+PDE_IDENT_ATTR,%eax +#else movl %eax,pa(initial_page_table+0xffc) #endif @@ -666,6 +558,7 @@ ENTRY(setup_once_ref) __PAGE_ALIGNED_BSS .align PAGE_SIZE #ifdef CONFIG_X86_PAE +.globl initial_pg_pmd initial_pg_pmd: .fill 1024*KPMDS,4,0 #else |