diff options
Diffstat (limited to 'arch/mips/include/asm/pgtable-32.h')
| -rw-r--r-- | arch/mips/include/asm/pgtable-32.h | 62 |
1 files changed, 54 insertions, 8 deletions
diff --git a/arch/mips/include/asm/pgtable-32.h b/arch/mips/include/asm/pgtable-32.h index 74afe8c76bdd..ba967148b016 100644 --- a/arch/mips/include/asm/pgtable-32.h +++ b/arch/mips/include/asm/pgtable-32.h @@ -23,6 +23,24 @@ #include <asm/highmem.h> #endif +/* + * Regarding 32-bit MIPS huge page support (and the tradeoff it entails): + * + * We use the same huge page sizes as 64-bit MIPS. Assuming a 4KB page size, + * our 2-level table layout would normally have a PGD entry cover a contiguous + * 4MB virtual address region (pointing to a 4KB PTE page of 1,024 32-bit pte_t + * pointers, each pointing to a 4KB physical page). The problem is that 4MB, + * spanning both halves of a TLB EntryLo0,1 pair, requires 2MB hardware page + * support, not one of the standard supported sizes (1MB,4MB,16MB,...). + * To correct for this, when huge pages are enabled, we halve the number of + * pointers a PTE page holds, making its last half go to waste. Correspondingly, + * we double the number of PGD pages. Overall, page table memory overhead + * increases to match 64-bit MIPS, but PTE lookups remain CPU cache-friendly. + * + * NOTE: We don't yet support huge pages if extended-addressing is enabled + * (i.e. EVA, XPA, 36-bit Alchemy/Netlogic). + */ + extern int temp_tlb_entry; /* @@ -44,7 +62,12 @@ extern int add_temporary_entry(unsigned long entrylo0, unsigned long entrylo1, */ /* PGDIR_SHIFT determines what a third-level page table entry can map */ -#define PGDIR_SHIFT (2 * PAGE_SHIFT + PTE_ORDER - PTE_T_LOG2) +#if defined(CONFIG_MIPS_HUGE_TLB_SUPPORT) && !defined(CONFIG_PHYS_ADDR_T_64BIT) +# define PGDIR_SHIFT (2 * PAGE_SHIFT + PTE_ORDER - PTE_T_LOG2 - 1) +#else +# define PGDIR_SHIFT (2 * PAGE_SHIFT + PTE_ORDER - PTE_T_LOG2) +#endif + #define PGDIR_SIZE (1UL << PGDIR_SHIFT) #define PGDIR_MASK (~(PGDIR_SIZE-1)) @@ -52,14 +75,23 @@ extern int add_temporary_entry(unsigned long entrylo0, unsigned long entrylo1, * Entries per page directory level: we use two-level, so * we don't really have any PUD/PMD directory physically. */ -#define __PGD_ORDER (32 - 3 * PAGE_SHIFT + PGD_T_LOG2 + PTE_T_LOG2) +#if defined(CONFIG_MIPS_HUGE_TLB_SUPPORT) && !defined(CONFIG_PHYS_ADDR_T_64BIT) +# define __PGD_ORDER (32 - 3 * PAGE_SHIFT + PGD_T_LOG2 + PTE_T_LOG2 + 1) +#else +# define __PGD_ORDER (32 - 3 * PAGE_SHIFT + PGD_T_LOG2 + PTE_T_LOG2) +#endif + #define PGD_ORDER (__PGD_ORDER >= 0 ? __PGD_ORDER : 0) #define PUD_ORDER aieeee_attempt_to_allocate_pud -#define PMD_ORDER 1 +#define PMD_ORDER aieeee_attempt_to_allocate_pmd #define PTE_ORDER 0 #define PTRS_PER_PGD (USER_PTRS_PER_PGD * 2) -#define PTRS_PER_PTE ((PAGE_SIZE << PTE_ORDER) / sizeof(pte_t)) +#if defined(CONFIG_MIPS_HUGE_TLB_SUPPORT) && !defined(CONFIG_PHYS_ADDR_T_64BIT) +# define PTRS_PER_PTE ((PAGE_SIZE << PTE_ORDER) / sizeof(pte_t) / 2) +#else +# define PTRS_PER_PTE ((PAGE_SIZE << PTE_ORDER) / sizeof(pte_t)) +#endif #define USER_PTRS_PER_PGD (0x80000000UL/PGDIR_SIZE) #define FIRST_USER_ADDRESS 0UL @@ -87,7 +119,7 @@ extern int add_temporary_entry(unsigned long entrylo0, unsigned long entrylo1, extern void load_pgd(unsigned long pg_dir); -extern pte_t invalid_pte_table[PAGE_SIZE/sizeof(pte_t)]; +extern pte_t invalid_pte_table[PTRS_PER_PTE]; /* * Empty pgd/pmd entries point to the invalid_pte_table. @@ -97,7 +129,19 @@ static inline int pmd_none(pmd_t pmd) return pmd_val(pmd) == (unsigned long) invalid_pte_table; } -#define pmd_bad(pmd) (pmd_val(pmd) & ~PAGE_MASK) +static inline int pmd_bad(pmd_t pmd) +{ +#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT + /* pmd_huge(pmd) but inline */ + if (unlikely(pmd_val(pmd) & _PAGE_HUGE)) + return 0; +#endif + + if (unlikely(pmd_val(pmd) & ~PAGE_MASK)) + return 1; + + return 0; +} static inline int pmd_present(pmd_t pmd) { @@ -146,6 +190,7 @@ static inline pte_t pfn_pte(unsigned long pfn, pgprot_t prot) #else #define pte_pfn(x) ((unsigned long)((x).pte >> _PFN_SHIFT)) #define pfn_pte(pfn, prot) __pte(((unsigned long long)(pfn) << _PFN_SHIFT) | pgprot_val(prot)) +#define pfn_pmd(pfn, prot) __pmd(((unsigned long long)(pfn) << _PFN_SHIFT) | pgprot_val(prot)) #endif #endif /* defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32) */ @@ -159,6 +204,7 @@ static inline pte_t pfn_pte(unsigned long pfn, pgprot_t prot) #define pgd_offset_k(address) pgd_offset(&init_mm, address) #define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1)) +#define pmd_index(address) (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1)) /* to find an entry in a page-table-directory */ #define pgd_offset(mm, addr) ((mm)->pgd + pgd_index(addr)) @@ -175,7 +221,7 @@ static inline pte_t pfn_pte(unsigned long pfn, pgprot_t prot) ((pte_t *)page_address(pmd_page(*(dir))) + __pte_offset(address)) #define pte_unmap(pte) ((void)(pte)) -#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX) +#if defined(CONFIG_CPU_R3K_TLB) /* Swap entries must have VALID bit cleared. */ #define __swp_type(x) (((x).val >> 10) & 0x1f) @@ -220,6 +266,6 @@ static inline pte_t pfn_pte(unsigned long pfn, pgprot_t prot) #endif /* defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32) */ -#endif /* defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX) */ +#endif /* defined(CONFIG_CPU_R3K_TLB) */ #endif /* _ASM_PGTABLE_32_H */ |