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Diffstat (limited to 'include/asm-sh64/mmu_context.h')
| -rw-r--r-- | include/asm-sh64/mmu_context.h | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/include/asm-sh64/mmu_context.h b/include/asm-sh64/mmu_context.h new file mode 100644 index 00000000000..f062e151327 --- /dev/null +++ b/include/asm-sh64/mmu_context.h @@ -0,0 +1,209 @@ +#ifndef __ASM_SH64_MMU_CONTEXT_H +#define __ASM_SH64_MMU_CONTEXT_H + +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * include/asm-sh64/mmu_context.h + * + * Copyright (C) 2000, 2001 Paolo Alberelli + * Copyright (C) 2003 Paul Mundt + * + * ASID handling idea taken from MIPS implementation. + * + */ + +#ifndef __ASSEMBLY__ + +/* + * Cache of MMU context last used. + * + * The MMU "context" consists of two things: + * (a) TLB cache version (or cycle, top 24 bits of mmu_context_cache) + * (b) ASID (Address Space IDentifier, bottom 8 bits of mmu_context_cache) + */ +extern unsigned long mmu_context_cache; + +#include <linux/config.h> +#include <asm/page.h> + + +/* Current mm's pgd */ +extern pgd_t *mmu_pdtp_cache; + +#define SR_ASID_MASK 0xffffffffff00ffffULL +#define SR_ASID_SHIFT 16 + +#define MMU_CONTEXT_ASID_MASK 0x000000ff +#define MMU_CONTEXT_VERSION_MASK 0xffffff00 +#define MMU_CONTEXT_FIRST_VERSION 0x00000100 +#define NO_CONTEXT 0 + +/* ASID is 8-bit value, so it can't be 0x100 */ +#define MMU_NO_ASID 0x100 + + +/* + * Virtual Page Number mask + */ +#define MMU_VPN_MASK 0xfffff000 + +extern __inline__ void +get_new_mmu_context(struct mm_struct *mm) +{ + extern void flush_tlb_all(void); + extern void flush_cache_all(void); + + 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. */ + flush_tlb_all(); + /* We have to flush all caches as ASIDs are + used in cache */ + flush_cache_all(); + /* Fix version if needed. + Note that we avoid version #0/asid #0 to distingush NO_CONTEXT. */ + if (!mc) + mmu_context_cache = mc = MMU_CONTEXT_FIRST_VERSION; + } + mm->context = 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 ^ 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) +{ + mm->context = NO_CONTEXT; + + return 0; +} + +/* + * Destroy context related info for an mm_struct that is about + * to be put to rest. + */ +static inline void destroy_context(struct mm_struct *mm) +{ + extern void flush_tlb_mm(struct mm_struct *mm); + + /* Well, at least free TLB entries */ + flush_tlb_mm(mm); +} + +#endif /* __ASSEMBLY__ */ + +/* Common defines */ +#define TLB_STEP 0x00000010 +#define TLB_PTEH 0x00000000 +#define TLB_PTEL 0x00000008 + +/* PTEH defines */ +#define PTEH_ASID_SHIFT 2 +#define PTEH_VALID 0x0000000000000001 +#define PTEH_SHARED 0x0000000000000002 +#define PTEH_MATCH_ASID 0x00000000000003ff + +#ifndef __ASSEMBLY__ +/* This has to be a common function because the next location to fill + * information is shared. */ +extern void __do_tlb_refill(unsigned long address, unsigned long long is_text_not_data, pte_t *pte); + +/* Profiling counter. */ +#ifdef CONFIG_SH64_PROC_TLB +extern unsigned long long calls_to_do_fast_page_fault; +#endif + +static inline unsigned long get_asid(void) +{ + unsigned long long sr; + + asm volatile ("getcon " __SR ", %0\n\t" + : "=r" (sr)); + + sr = (sr >> SR_ASID_SHIFT) & MMU_CONTEXT_ASID_MASK; + return (unsigned long) sr; +} + +/* Set ASID into SR */ +static inline void set_asid(unsigned long asid) +{ + unsigned long long sr, pc; + + asm volatile ("getcon " __SR ", %0" : "=r" (sr)); + + sr = (sr & SR_ASID_MASK) | (asid << SR_ASID_SHIFT); + + /* + * It is possible that this function may be inlined and so to avoid + * the assembler reporting duplicate symbols we make use of the gas trick + * of generating symbols using numerics and forward reference. + */ + asm volatile ("movi 1, %1\n\t" + "shlli %1, 28, %1\n\t" + "or %0, %1, %1\n\t" + "putcon %1, " __SR "\n\t" + "putcon %0, " __SSR "\n\t" + "movi 1f, %1\n\t" + "ori %1, 1 , %1\n\t" + "putcon %1, " __SPC "\n\t" + "rte\n" + "1:\n\t" + : "=r" (sr), "=r" (pc) : "0" (sr)); +} + +/* + * 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 & MMU_CONTEXT_ASID_MASK); +} + + +static __inline__ void switch_mm(struct mm_struct *prev, + struct mm_struct *next, + struct task_struct *tsk) +{ + if (prev != next) { + mmu_pdtp_cache = next->pgd; + activate_context(next); + } +} + +#define deactivate_mm(tsk,mm) do { } while (0) + +#define activate_mm(prev, next) \ + switch_mm((prev),(next),NULL) + +static inline void +enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk) +{ +} + +#endif /* __ASSEMBLY__ */ + +#endif /* __ASM_SH64_MMU_CONTEXT_H */ |