diff options
Diffstat (limited to 'kernel/arch/m32r/include/asm/mmu_context.h')
| -rw-r--r-- | kernel/arch/m32r/include/asm/mmu_context.h | 164 |
1 files changed, 164 insertions, 0 deletions
diff --git a/kernel/arch/m32r/include/asm/mmu_context.h b/kernel/arch/m32r/include/asm/mmu_context.h new file mode 100644 index 000000000..9fc78fc44 --- /dev/null +++ b/kernel/arch/m32r/include/asm/mmu_context.h @@ -0,0 +1,164 @@ +#ifndef _ASM_M32R_MMU_CONTEXT_H +#define _ASM_M32R_MMU_CONTEXT_H +#ifdef __KERNEL__ + +#include <asm/m32r.h> + +#define MMU_CONTEXT_ASID_MASK (0x000000FF) +#define MMU_CONTEXT_VERSION_MASK (0xFFFFFF00) +#define MMU_CONTEXT_FIRST_VERSION (0x00000100) +#define NO_CONTEXT (0x00000000) + +#ifndef __ASSEMBLY__ + +#include <linux/atomic.h> +#include <asm/pgalloc.h> +#include <asm/mmu.h> +#include <asm/tlbflush.h> +#include <asm-generic/mm_hooks.h> + +/* + * Cache of MMU context last used. + */ +#ifndef CONFIG_SMP +extern unsigned long mmu_context_cache_dat; +#define mmu_context_cache mmu_context_cache_dat +#define mm_context(mm) mm->context +#else /* not CONFIG_SMP */ +extern unsigned long mmu_context_cache_dat[]; +#define mmu_context_cache mmu_context_cache_dat[smp_processor_id()] +#define mm_context(mm) mm->context[smp_processor_id()] +#endif /* not CONFIG_SMP */ + +#define set_tlb_tag(entry, tag) (*entry = (tag & PAGE_MASK)|get_asid()) +#define set_tlb_data(entry, data) (*entry = (data | _PAGE_PRESENT)) + +#ifdef CONFIG_MMU +#define enter_lazy_tlb(mm, tsk) do { } while (0) + +static inline void get_new_mmu_context(struct mm_struct *mm) +{ + unsigned long mc = ++mmu_context_cache; + + if (!(mc & MMU_CONTEXT_ASID_MASK)) { + /* We exhaust ASID of this version. + Flush all TLB and start new cycle. */ + local_flush_tlb_all(); + /* Fix version if needed. + Note that we avoid version #0 to distinguish NO_CONTEXT. */ + if (!mc) + mmu_context_cache = mc = MMU_CONTEXT_FIRST_VERSION; + } + mm_context(mm) = mc; +} + +/* + * Get MMU context if needed. + */ +static inline void get_mmu_context(struct mm_struct *mm) +{ + if (mm) { + unsigned long mc = mmu_context_cache; + + /* Check if we have old version of context. + If it's old, we need to get new context with new version. */ + if ((mm_context(mm) ^ mc) & MMU_CONTEXT_VERSION_MASK) + get_new_mmu_context(mm); + } +} + +/* + * Initialize the context related info for a new mm_struct + * instance. + */ +static inline int init_new_context(struct task_struct *tsk, + struct mm_struct *mm) +{ +#ifndef CONFIG_SMP + mm->context = NO_CONTEXT; +#else /* CONFIG_SMP */ + int num_cpus = num_online_cpus(); + int i; + + for (i = 0 ; i < num_cpus ; i++) + mm->context[i] = NO_CONTEXT; +#endif /* CONFIG_SMP */ + + return 0; +} + +/* + * Destroy context related info for an mm_struct that is about + * to be put to rest. + */ +#define destroy_context(mm) do { } while (0) + +static inline void set_asid(unsigned long asid) +{ + *(volatile unsigned long *)MASID = (asid & MMU_CONTEXT_ASID_MASK); +} + +static inline unsigned long get_asid(void) +{ + unsigned long asid; + + asid = *(volatile long *)MASID; + asid &= MMU_CONTEXT_ASID_MASK; + + return asid; +} + +/* + * After we have set current->mm to a new value, this activates + * the context for the new mm so we see the new mappings. + */ +static inline void activate_context(struct mm_struct *mm) +{ + get_mmu_context(mm); + set_asid(mm_context(mm) & MMU_CONTEXT_ASID_MASK); +} + +static inline void switch_mm(struct mm_struct *prev, + struct mm_struct *next, struct task_struct *tsk) +{ +#ifdef CONFIG_SMP + int cpu = smp_processor_id(); +#endif /* CONFIG_SMP */ + + if (prev != next) { +#ifdef CONFIG_SMP + cpumask_set_cpu(cpu, mm_cpumask(next)); +#endif /* CONFIG_SMP */ + /* Set MPTB = next->pgd */ + *(volatile unsigned long *)MPTB = (unsigned long)next->pgd; + activate_context(next); + } +#ifdef CONFIG_SMP + else + if (!cpumask_test_and_set_cpu(cpu, mm_cpumask(next))) + activate_context(next); +#endif /* CONFIG_SMP */ +} + +#define deactivate_mm(tsk, mm) do { } while (0) + +#define activate_mm(prev, next) \ + switch_mm((prev), (next), NULL) + +#else /* not CONFIG_MMU */ +#define get_mmu_context(mm) do { } while (0) +#define init_new_context(tsk,mm) (0) +#define destroy_context(mm) do { } while (0) +#define set_asid(asid) do { } while (0) +#define get_asid() (0) +#define activate_context(mm) do { } while (0) +#define switch_mm(prev,next,tsk) do { } while (0) +#define deactivate_mm(mm,tsk) do { } while (0) +#define activate_mm(prev,next) do { } while (0) +#define enter_lazy_tlb(mm,tsk) do { } while (0) +#endif /* not CONFIG_MMU */ + +#endif /* not __ASSEMBLY__ */ + +#endif /* __KERNEL__ */ +#endif /* _ASM_M32R_MMU_CONTEXT_H */ |