1 #ifndef __M68K_MMU_CONTEXT_H 2 #define __M68K_MMU_CONTEXT_H 3 4 #include <asm-generic/mm_hooks.h> 5 6 static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk) 7 { 8 } 9 10 #ifdef CONFIG_MMU 11 12 #if defined(CONFIG_COLDFIRE) 13 14 #include <asm/atomic.h> 15 #include <asm/bitops.h> 16 #include <asm/mcfmmu.h> 17 #include <asm/mmu.h> 18 19 #define NO_CONTEXT 256 20 #define LAST_CONTEXT 255 21 #define FIRST_CONTEXT 1 22 23 extern unsigned long context_map[]; 24 extern mm_context_t next_mmu_context; 25 26 extern atomic_t nr_free_contexts; 27 extern struct mm_struct *context_mm[LAST_CONTEXT+1]; 28 extern void steal_context(void); 29 30 static inline void get_mmu_context(struct mm_struct *mm) 31 { 32 mm_context_t ctx; 33 34 if (mm->context != NO_CONTEXT) 35 return; 36 while (atomic_dec_and_test_lt(&nr_free_contexts)) { 37 atomic_inc(&nr_free_contexts); 38 steal_context(); 39 } 40 ctx = next_mmu_context; 41 while (test_and_set_bit(ctx, context_map)) { 42 ctx = find_next_zero_bit(context_map, LAST_CONTEXT+1, ctx); 43 if (ctx > LAST_CONTEXT) 44 ctx = 0; 45 } 46 next_mmu_context = (ctx + 1) & LAST_CONTEXT; 47 mm->context = ctx; 48 context_mm[ctx] = mm; 49 } 50 51 /* 52 * Set up the context for a new address space. 53 */ 54 #define init_new_context(tsk, mm) (((mm)->context = NO_CONTEXT), 0) 55 56 /* 57 * We're finished using the context for an address space. 58 */ 59 static inline void destroy_context(struct mm_struct *mm) 60 { 61 if (mm->context != NO_CONTEXT) { 62 clear_bit(mm->context, context_map); 63 mm->context = NO_CONTEXT; 64 atomic_inc(&nr_free_contexts); 65 } 66 } 67 68 static inline void set_context(mm_context_t context, pgd_t *pgd) 69 { 70 __asm__ __volatile__ ("movec %0,%%asid" : : "d" (context)); 71 } 72 73 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, 74 struct task_struct *tsk) 75 { 76 get_mmu_context(tsk->mm); 77 set_context(tsk->mm->context, next->pgd); 78 } 79 80 /* 81 * After we have set current->mm to a new value, this activates 82 * the context for the new mm so we see the new mappings. 83 */ 84 static inline void activate_mm(struct mm_struct *active_mm, 85 struct mm_struct *mm) 86 { 87 get_mmu_context(mm); 88 set_context(mm->context, mm->pgd); 89 } 90 91 #define deactivate_mm(tsk, mm) do { } while (0) 92 93 extern void mmu_context_init(void); 94 #define prepare_arch_switch(next) load_ksp_mmu(next) 95 96 static inline void load_ksp_mmu(struct task_struct *task) 97 { 98 unsigned long flags; 99 struct mm_struct *mm; 100 int asid; 101 pgd_t *pgd; 102 pmd_t *pmd; 103 pte_t *pte; 104 unsigned long mmuar; 105 106 local_irq_save(flags); 107 mmuar = task->thread.ksp; 108 109 /* Search for a valid TLB entry, if one is found, don't remap */ 110 mmu_write(MMUAR, mmuar); 111 mmu_write(MMUOR, MMUOR_STLB | MMUOR_ADR); 112 if (mmu_read(MMUSR) & MMUSR_HIT) 113 goto end; 114 115 if (mmuar >= PAGE_OFFSET) { 116 mm = &init_mm; 117 } else { 118 pr_info("load_ksp_mmu: non-kernel mm found: 0x%p\n", task->mm); 119 mm = task->mm; 120 } 121 122 if (!mm) 123 goto bug; 124 125 pgd = pgd_offset(mm, mmuar); 126 if (pgd_none(*pgd)) 127 goto bug; 128 129 pmd = pmd_offset(pgd, mmuar); 130 if (pmd_none(*pmd)) 131 goto bug; 132 133 pte = (mmuar >= PAGE_OFFSET) ? pte_offset_kernel(pmd, mmuar) 134 : pte_offset_map(pmd, mmuar); 135 if (pte_none(*pte) || !pte_present(*pte)) 136 goto bug; 137 138 set_pte(pte, pte_mkyoung(*pte)); 139 asid = mm->context & 0xff; 140 if (!pte_dirty(*pte) && mmuar <= PAGE_OFFSET) 141 set_pte(pte, pte_wrprotect(*pte)); 142 143 mmu_write(MMUTR, (mmuar & PAGE_MASK) | (asid << MMUTR_IDN) | 144 (((int)(pte->pte) & (int)CF_PAGE_MMUTR_MASK) 145 >> CF_PAGE_MMUTR_SHIFT) | MMUTR_V); 146 147 mmu_write(MMUDR, (pte_val(*pte) & PAGE_MASK) | 148 ((pte->pte) & CF_PAGE_MMUDR_MASK) | MMUDR_SZ_8KB | MMUDR_X); 149 150 mmu_write(MMUOR, MMUOR_ACC | MMUOR_UAA); 151 152 goto end; 153 154 bug: 155 pr_info("ksp load failed: mm=0x%p ksp=0x08%lx\n", mm, mmuar); 156 end: 157 local_irq_restore(flags); 158 } 159 160 #elif defined(CONFIG_SUN3) 161 #include <asm/sun3mmu.h> 162 #include <linux/sched.h> 163 164 extern unsigned long get_free_context(struct mm_struct *mm); 165 extern void clear_context(unsigned long context); 166 167 /* set the context for a new task to unmapped */ 168 static inline int init_new_context(struct task_struct *tsk, 169 struct mm_struct *mm) 170 { 171 mm->context = SUN3_INVALID_CONTEXT; 172 return 0; 173 } 174 175 /* find the context given to this process, and if it hasn't already 176 got one, go get one for it. */ 177 static inline void get_mmu_context(struct mm_struct *mm) 178 { 179 if (mm->context == SUN3_INVALID_CONTEXT) 180 mm->context = get_free_context(mm); 181 } 182 183 /* flush context if allocated... */ 184 static inline void destroy_context(struct mm_struct *mm) 185 { 186 if (mm->context != SUN3_INVALID_CONTEXT) 187 clear_context(mm->context); 188 } 189 190 static inline void activate_context(struct mm_struct *mm) 191 { 192 get_mmu_context(mm); 193 sun3_put_context(mm->context); 194 } 195 196 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, 197 struct task_struct *tsk) 198 { 199 activate_context(tsk->mm); 200 } 201 202 #define deactivate_mm(tsk, mm) do { } while (0) 203 204 static inline void activate_mm(struct mm_struct *prev_mm, 205 struct mm_struct *next_mm) 206 { 207 activate_context(next_mm); 208 } 209 210 #else 211 212 #include <asm/setup.h> 213 #include <asm/page.h> 214 #include <asm/pgalloc.h> 215 216 static inline int init_new_context(struct task_struct *tsk, 217 struct mm_struct *mm) 218 { 219 mm->context = virt_to_phys(mm->pgd); 220 return 0; 221 } 222 223 #define destroy_context(mm) do { } while(0) 224 225 static inline void switch_mm_0230(struct mm_struct *mm) 226 { 227 unsigned long crp[2] = { 228 0x80000000 | _PAGE_TABLE, mm->context 229 }; 230 unsigned long tmp; 231 232 asm volatile (".chip 68030"); 233 234 /* flush MC68030/MC68020 caches (they are virtually addressed) */ 235 asm volatile ( 236 "movec %%cacr,%0;" 237 "orw %1,%0; " 238 "movec %0,%%cacr" 239 : "=d" (tmp) : "di" (FLUSH_I_AND_D)); 240 241 /* Switch the root pointer. For a 030-only kernel, 242 * avoid flushing the whole ATC, we only need to 243 * flush the user entries. The 68851 does this by 244 * itself. Avoid a runtime check here. 245 */ 246 asm volatile ( 247 #ifdef CPU_M68030_ONLY 248 "pmovefd %0,%%crp; " 249 "pflush #0,#4" 250 #else 251 "pmove %0,%%crp" 252 #endif 253 : : "m" (crp[0])); 254 255 asm volatile (".chip 68k"); 256 } 257 258 static inline void switch_mm_0460(struct mm_struct *mm) 259 { 260 asm volatile (".chip 68040"); 261 262 /* flush address translation cache (user entries) */ 263 asm volatile ("pflushan"); 264 265 /* switch the root pointer */ 266 asm volatile ("movec %0,%%urp" : : "r" (mm->context)); 267 268 if (CPU_IS_060) { 269 unsigned long tmp; 270 271 /* clear user entries in the branch cache */ 272 asm volatile ( 273 "movec %%cacr,%0; " 274 "orl %1,%0; " 275 "movec %0,%%cacr" 276 : "=d" (tmp): "di" (0x00200000)); 277 } 278 279 asm volatile (".chip 68k"); 280 } 281 282 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, struct task_struct *tsk) 283 { 284 if (prev != next) { 285 if (CPU_IS_020_OR_030) 286 switch_mm_0230(next); 287 else 288 switch_mm_0460(next); 289 } 290 } 291 292 #define deactivate_mm(tsk,mm) do { } while (0) 293 294 static inline void activate_mm(struct mm_struct *prev_mm, 295 struct mm_struct *next_mm) 296 { 297 next_mm->context = virt_to_phys(next_mm->pgd); 298 299 if (CPU_IS_020_OR_030) 300 switch_mm_0230(next_mm); 301 else 302 switch_mm_0460(next_mm); 303 } 304 305 #endif 306 307 #else /* !CONFIG_MMU */ 308 309 static inline int init_new_context(struct task_struct *tsk, struct mm_struct *mm) 310 { 311 return 0; 312 } 313 314 315 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, struct task_struct *tsk) 316 { 317 } 318 319 #define destroy_context(mm) do { } while (0) 320 #define deactivate_mm(tsk,mm) do { } while (0) 321 322 static inline void activate_mm(struct mm_struct *prev_mm, struct mm_struct *next_mm) 323 { 324 } 325 326 #endif /* CONFIG_MMU */ 327 #endif /* __M68K_MMU_CONTEXT_H */ 328