| Chen Liqin | 6bc9a39 | 2009-06-12 22:01:00 +0800 | [diff] [blame] | 1 | #ifndef _ASM_SCORE_MMU_CONTEXT_H |
| 2 | #define _ASM_SCORE_MMU_CONTEXT_H |
| 3 | |
| 4 | #include <linux/errno.h> |
| 5 | #include <linux/sched.h> |
| 6 | #include <linux/slab.h> |
| 7 | #include <asm-generic/mm_hooks.h> |
| 8 | |
| 9 | #include <asm/cacheflush.h> |
| 10 | #include <asm/tlbflush.h> |
| 11 | #include <asm/scoreregs.h> |
| 12 | |
| 13 | /* |
| 14 | * For the fast tlb miss handlers, we keep a per cpu array of pointers |
| 15 | * to the current pgd for each processor. Also, the proc. id is stuffed |
| 16 | * into the context register. |
| 17 | */ |
| 18 | extern unsigned long asid_cache; |
| 19 | extern unsigned long pgd_current; |
| 20 | |
| 21 | #define TLBMISS_HANDLER_SETUP_PGD(pgd) (pgd_current = (unsigned long)(pgd)) |
| 22 | |
| 23 | #define TLBMISS_HANDLER_SETUP() \ |
| 24 | do { \ |
| 25 | write_c0_context(0); \ |
| 26 | TLBMISS_HANDLER_SETUP_PGD(swapper_pg_dir) \ |
| 27 | } while (0) |
| 28 | |
| 29 | /* |
| 30 | * All unused by hardware upper bits will be considered |
| 31 | * as a software asid extension. |
| 32 | */ |
| 33 | #define ASID_VERSION_MASK 0xfffff000 |
| 34 | #define ASID_FIRST_VERSION 0x1000 |
| 35 | |
| 36 | /* PEVN --------- VPN ---------- --ASID--- -NA- */ |
| 37 | /* binary: 0000 0000 0000 0000 0000 0000 0001 0000 */ |
| 38 | /* binary: 0000 0000 0000 0000 0000 1111 1111 0000 */ |
| 39 | #define ASID_INC 0x10 |
| 40 | #define ASID_MASK 0xff0 |
| 41 | |
| 42 | static inline void enter_lazy_tlb(struct mm_struct *mm, |
| 43 | struct task_struct *tsk) |
| 44 | {} |
| 45 | |
| 46 | static inline void |
| 47 | get_new_mmu_context(struct mm_struct *mm) |
| 48 | { |
| 49 | unsigned long asid = asid_cache + ASID_INC; |
| 50 | |
| 51 | if (!(asid & ASID_MASK)) { |
| 52 | local_flush_tlb_all(); /* start new asid cycle */ |
| 53 | if (!asid) /* fix version if needed */ |
| 54 | asid = ASID_FIRST_VERSION; |
| 55 | } |
| 56 | |
| 57 | mm->context = asid; |
| 58 | asid_cache = asid; |
| 59 | } |
| 60 | |
| 61 | /* |
| 62 | * Initialize the context related info for a new mm_struct |
| 63 | * instance. |
| 64 | */ |
| 65 | static inline int |
| 66 | init_new_context(struct task_struct *tsk, struct mm_struct *mm) |
| 67 | { |
| 68 | mm->context = 0; |
| 69 | return 0; |
| 70 | } |
| 71 | |
| 72 | static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, |
| 73 | struct task_struct *tsk) |
| 74 | { |
| 75 | unsigned long flags; |
| 76 | |
| 77 | local_irq_save(flags); |
| 78 | if ((next->context ^ asid_cache) & ASID_VERSION_MASK) |
| 79 | get_new_mmu_context(next); |
| 80 | |
| 81 | pevn_set(next->context); |
| 82 | TLBMISS_HANDLER_SETUP_PGD(next->pgd); |
| 83 | local_irq_restore(flags); |
| 84 | } |
| 85 | |
| 86 | /* |
| 87 | * Destroy context related info for an mm_struct that is about |
| 88 | * to be put to rest. |
| 89 | */ |
| 90 | static inline void destroy_context(struct mm_struct *mm) |
| 91 | {} |
| 92 | |
| 93 | static inline void |
| 94 | deactivate_mm(struct task_struct *task, struct mm_struct *mm) |
| 95 | {} |
| 96 | |
| 97 | /* |
| 98 | * After we have set current->mm to a new value, this activates |
| 99 | * the context for the new mm so we see the new mappings. |
| 100 | */ |
| 101 | static inline void |
| 102 | activate_mm(struct mm_struct *prev, struct mm_struct *next) |
| 103 | { |
| 104 | unsigned long flags; |
| 105 | |
| 106 | local_irq_save(flags); |
| 107 | get_new_mmu_context(next); |
| 108 | pevn_set(next->context); |
| 109 | TLBMISS_HANDLER_SETUP_PGD(next->pgd); |
| 110 | local_irq_restore(flags); |
| 111 | } |
| 112 | |
| 113 | #endif /* _ASM_SCORE_MMU_CONTEXT_H */ |
