1#ifndef __ASM_SH64_MMU_CONTEXT_H 2#define __ASM_SH64_MMU_CONTEXT_H 3 4/* 5 * This file is subject to the terms and conditions of the GNU General Public 6 * License. See the file "COPYING" in the main directory of this archive 7 * for more details. 8 * 9 * include/asm-sh64/mmu_context.h 10 * 11 * Copyright (C) 2000, 2001 Paolo Alberelli 12 * Copyright (C) 2003 Paul Mundt 13 * 14 * ASID handling idea taken from MIPS implementation. 15 * 16 */ 17 18#ifndef __ASSEMBLY__ 19 20/* 21 * Cache of MMU context last used. 22 * 23 * The MMU "context" consists of two things: 24 * (a) TLB cache version (or cycle, top 24 bits of mmu_context_cache) 25 * (b) ASID (Address Space IDentifier, bottom 8 bits of mmu_context_cache) 26 */ 27extern unsigned long mmu_context_cache; 28 29#include <asm/page.h> 30#include <asm-generic/mm_hooks.h> 31 32/* Current mm's pgd */ 33extern pgd_t *mmu_pdtp_cache; 34 35#define SR_ASID_MASK 0xffffffffff00ffffULL 36#define SR_ASID_SHIFT 16 37 38#define MMU_CONTEXT_ASID_MASK 0x000000ff 39#define MMU_CONTEXT_VERSION_MASK 0xffffff00 40#define MMU_CONTEXT_FIRST_VERSION 0x00000100 41#define NO_CONTEXT 0 42 43/* ASID is 8-bit value, so it can't be 0x100 */ 44#define MMU_NO_ASID 0x100 45 46 47/* 48 * Virtual Page Number mask 49 */ 50#define MMU_VPN_MASK 0xfffff000 51 52static inline void 53get_new_mmu_context(struct mm_struct *mm) 54{ 55 extern void flush_tlb_all(void); 56 extern void flush_cache_all(void); 57 58 unsigned long mc = ++mmu_context_cache; 59 60 if (!(mc & MMU_CONTEXT_ASID_MASK)) { 61 /* We exhaust ASID of this version. 62 Flush all TLB and start new cycle. */ 63 flush_tlb_all(); 64 /* We have to flush all caches as ASIDs are 65 used in cache */ 66 flush_cache_all(); 67 /* Fix version if needed. 68 Note that we avoid version #0/asid #0 to distingush NO_CONTEXT. */ 69 if (!mc) 70 mmu_context_cache = mc = MMU_CONTEXT_FIRST_VERSION; 71 } 72 mm->context = mc; 73} 74 75/* 76 * Get MMU context if needed. 77 */ 78static __inline__ void 79get_mmu_context(struct mm_struct *mm) 80{ 81 if (mm) { 82 unsigned long mc = mmu_context_cache; 83 /* Check if we have old version of context. 84 If it's old, we need to get new context with new version. */ 85 if ((mm->context ^ mc) & MMU_CONTEXT_VERSION_MASK) 86 get_new_mmu_context(mm); 87 } 88} 89 90/* 91 * Initialize the context related info for a new mm_struct 92 * instance. 93 */ 94static inline int init_new_context(struct task_struct *tsk, 95 struct mm_struct *mm) 96{ 97 mm->context = NO_CONTEXT; 98 99 return 0; 100} 101 102/* 103 * Destroy context related info for an mm_struct that is about 104 * to be put to rest. 105 */ 106static inline void destroy_context(struct mm_struct *mm) 107{ 108 extern void flush_tlb_mm(struct mm_struct *mm); 109 110 /* Well, at least free TLB entries */ 111 flush_tlb_mm(mm); 112} 113 114#endif /* __ASSEMBLY__ */ 115 116/* Common defines */ 117#define TLB_STEP 0x00000010 118#define TLB_PTEH 0x00000000 119#define TLB_PTEL 0x00000008 120 121/* PTEH defines */ 122#define PTEH_ASID_SHIFT 2 123#define PTEH_VALID 0x0000000000000001 124#define PTEH_SHARED 0x0000000000000002 125#define PTEH_MATCH_ASID 0x00000000000003ff 126 127#ifndef __ASSEMBLY__ 128/* This has to be a common function because the next location to fill 129 * information is shared. */ 130extern void __do_tlb_refill(unsigned long address, unsigned long long is_text_not_data, pte_t *pte); 131 132/* Profiling counter. */ 133#ifdef CONFIG_SH64_PROC_TLB 134extern unsigned long long calls_to_do_fast_page_fault; 135#endif 136 137static inline unsigned long get_asid(void) 138{ 139 unsigned long long sr; 140 141 asm volatile ("getcon " __SR ", %0\n\t" 142 : "=r" (sr)); 143 144 sr = (sr >> SR_ASID_SHIFT) & MMU_CONTEXT_ASID_MASK; 145 return (unsigned long) sr; 146} 147 148/* Set ASID into SR */ 149static inline void set_asid(unsigned long asid) 150{ 151 unsigned long long sr, pc; 152 153 asm volatile ("getcon " __SR ", %0" : "=r" (sr)); 154 155 sr = (sr & SR_ASID_MASK) | (asid << SR_ASID_SHIFT); 156 157 /* 158 * It is possible that this function may be inlined and so to avoid 159 * the assembler reporting duplicate symbols we make use of the gas trick 160 * of generating symbols using numerics and forward reference. 161 */ 162 asm volatile ("movi 1, %1\n\t" 163 "shlli %1, 28, %1\n\t" 164 "or %0, %1, %1\n\t" 165 "putcon %1, " __SR "\n\t" 166 "putcon %0, " __SSR "\n\t" 167 "movi 1f, %1\n\t" 168 "ori %1, 1 , %1\n\t" 169 "putcon %1, " __SPC "\n\t" 170 "rte\n" 171 "1:\n\t" 172 : "=r" (sr), "=r" (pc) : "0" (sr)); 173} 174 175/* 176 * After we have set current->mm to a new value, this activates 177 * the context for the new mm so we see the new mappings. 178 */ 179static __inline__ void activate_context(struct mm_struct *mm) 180{ 181 get_mmu_context(mm); 182 set_asid(mm->context & MMU_CONTEXT_ASID_MASK); 183} 184 185 186static __inline__ void switch_mm(struct mm_struct *prev, 187 struct mm_struct *next, 188 struct task_struct *tsk) 189{ 190 if (prev != next) { 191 mmu_pdtp_cache = next->pgd; 192 activate_context(next); 193 } 194} 195 196#define deactivate_mm(tsk,mm) do { } while (0) 197 198#define activate_mm(prev, next) \ 199 switch_mm((prev),(next),NULL) 200 201static inline void 202enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk) 203{ 204} 205 206#endif /* __ASSEMBLY__ */ 207 208#endif /* __ASM_SH64_MMU_CONTEXT_H */ 209