diff options
Diffstat (limited to 'arch/arc/include/asm/pgtable.h')
| -rw-r--r-- | arch/arc/include/asm/pgtable.h | 56 |
1 files changed, 31 insertions, 25 deletions
diff --git a/arch/arc/include/asm/pgtable.h b/arch/arc/include/asm/pgtable.h index 57af2f05ae84..7d6c93e63adf 100644 --- a/arch/arc/include/asm/pgtable.h +++ b/arch/arc/include/asm/pgtable.h @@ -12,7 +12,7 @@ * - Utilise some unused free bits to confine PTE flags to 12 bits * This is a must for 4k pg-sz * - * vineetg: Mar 2011 - changes to accomodate MMU TLB Page Descriptor mods + * vineetg: Mar 2011 - changes to accommodate MMU TLB Page Descriptor mods * -TLB Locking never really existed, except for initial specs * -SILENT_xxx not needed for our port * -Per my request, MMU V3 changes the layout of some of the bits @@ -179,37 +179,44 @@ #define __S111 PAGE_U_X_W_R /**************************************************************** - * Page Table Lookup split + * 2 tier (PGD:PTE) software page walker * - * We implement 2 tier paging and since this is all software, we are free - * to customize the span of a PGD / PTE entry to suit us - * - * 32 bit virtual address + * [31] 32 bit virtual address [0] * ------------------------------------------------------- - * | BITS_FOR_PGD | BITS_FOR_PTE | BITS_IN_PAGE | + * | | <------------ PGDIR_SHIFT ----------> | + * | | | + * | BITS_FOR_PGD | BITS_FOR_PTE | <-- PAGE_SHIFT --> | * ------------------------------------------------------- * | | | * | | --> off in page frame - * | | * | ---> index into Page Table - * | * ----> index into Page Directory + * + * In a single page size configuration, only PAGE_SHIFT is fixed + * So both PGD and PTE sizing can be tweaked + * e.g. 8K page (PAGE_SHIFT 13) can have + * - PGDIR_SHIFT 21 -> 11:8:13 address split + * - PGDIR_SHIFT 24 -> 8:11:13 address split + * + * If Super Page is configured, PGDIR_SHIFT becomes fixed too, + * so the sizing flexibility is gone. */ -#define BITS_IN_PAGE PAGE_SHIFT - -/* Optimal Sizing of Pg Tbl - based on MMU page size */ -#if defined(CONFIG_ARC_PAGE_SIZE_8K) -#define BITS_FOR_PTE 8 /* 11:8:13 */ -#elif defined(CONFIG_ARC_PAGE_SIZE_16K) -#define BITS_FOR_PTE 8 /* 10:8:14 */ -#elif defined(CONFIG_ARC_PAGE_SIZE_4K) -#define BITS_FOR_PTE 9 /* 11:9:12 */ +#if defined(CONFIG_ARC_HUGEPAGE_16M) +#define PGDIR_SHIFT 24 +#elif defined(CONFIG_ARC_HUGEPAGE_2M) +#define PGDIR_SHIFT 21 +#else +/* + * Only Normal page support so "hackable" (see comment above) + * Default value provides 11:8:13 (8K), 11:9:12 (4K) + */ +#define PGDIR_SHIFT 21 #endif -#define BITS_FOR_PGD (32 - BITS_FOR_PTE - BITS_IN_PAGE) +#define BITS_FOR_PTE (PGDIR_SHIFT - PAGE_SHIFT) +#define BITS_FOR_PGD (32 - PGDIR_SHIFT) -#define PGDIR_SHIFT (32 - BITS_FOR_PGD) #define PGDIR_SIZE (1UL << PGDIR_SHIFT) /* vaddr span, not PDG sz */ #define PGDIR_MASK (~(PGDIR_SIZE-1)) @@ -271,15 +278,14 @@ static inline void pmd_set(pmd_t *pmdp, pte_t *ptep) #define pmd_present(x) (pmd_val(x)) #define pmd_clear(xp) do { pmd_val(*(xp)) = 0; } while (0) -#define pte_page(x) (mem_map + \ - (unsigned long)(((pte_val(x) - CONFIG_LINUX_LINK_BASE) >> \ - PAGE_SHIFT))) +#define pte_page(pte) \ + (mem_map + virt_to_pfn(pte_val(pte) - CONFIG_LINUX_LINK_BASE)) #define mk_pte(page, prot) pfn_pte(page_to_pfn(page), prot) -#define pte_pfn(pte) (pte_val(pte) >> PAGE_SHIFT) +#define pte_pfn(pte) virt_to_pfn(pte_val(pte)) #define pfn_pte(pfn, prot) (__pte(((pte_t)(pfn) << PAGE_SHIFT) | \ pgprot_val(prot))) -#define __pte_index(addr) (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)) +#define __pte_index(addr) (virt_to_pfn(addr) & (PTRS_PER_PTE - 1)) /* * pte_offset gets a @ptr to PMD entry (PGD in our 2-tier paging system) |
