1 #ifndef __M68K_MMU_CONTEXT_H 2 #define __M68K_MMU_CONTEXT_H 3 4 #include <asm-generic/mm_hooks.h> 5 #include <linux/mm_types.h> 6 7 static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk) 8 { 9 } 10 11 #ifdef CONFIG_MMU 12 13 #if defined(CONFIG_COLDFIRE) 14 15 #include <asm/atomic.h> 16 #include <asm/bitops.h> 17 #include <asm/mcfmmu.h> 18 #include <asm/mmu.h> 19 20 #define NO_CONTEXT 256 21 #define LAST_CONTEXT 255 22 #define FIRST_CONTEXT 1 23 24 extern unsigned long context_map[]; 25 extern mm_context_t next_mmu_context; 26 27 extern atomic_t nr_free_contexts; 28 extern struct mm_struct *context_mm[LAST_CONTEXT+1]; 29 extern void steal_context(void); 30 31 static inline void get_mmu_context(struct mm_struct *mm) 32 { 33 mm_context_t ctx; 34 35 if (mm->context != NO_CONTEXT) 36 return; 37 while (atomic_dec_and_test_lt(&nr_free_contexts)) { 38 atomic_inc(&nr_free_contexts); 39 steal_context(); 40 } 41 ctx = next_mmu_context; 42 while (test_and_set_bit(ctx, context_map)) { 43 ctx = find_next_zero_bit(context_map, LAST_CONTEXT+1, ctx); 44 if (ctx > LAST_CONTEXT) 45 ctx = 0; 46 } 47 next_mmu_context = (ctx + 1) & LAST_CONTEXT; 48 mm->context = ctx; 49 context_mm[ctx] = mm; 50 } 51 52 /* 53 * Set up the context for a new address space. 54 */ 55 #define init_new_context(tsk, mm) (((mm)->context = NO_CONTEXT), 0) 56 57 /* 58 * We're finished using the context for an address space. 59 */ 60 static inline void destroy_context(struct mm_struct *mm) 61 { 62 if (mm->context != NO_CONTEXT) { 63 clear_bit(mm->context, context_map); 64 mm->context = NO_CONTEXT; 65 atomic_inc(&nr_free_contexts); 66 } 67 } 68 69 static inline void set_context(mm_context_t context, pgd_t *pgd) 70 { 71 __asm__ __volatile__ ("movec %0,%%asid" : : "d" (context)); 72 } 73 74 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, 75 struct task_struct *tsk) 76 { 77 get_mmu_context(tsk->mm); 78 set_context(tsk->mm->context, next->pgd); 79 } 80 81 /* 82 * After we have set current->mm to a new value, this activates 83 * the context for the new mm so we see the new mappings. 84 */ 85 static inline void activate_mm(struct mm_struct *active_mm, 86 struct mm_struct *mm) 87 { 88 get_mmu_context(mm); 89 set_context(mm->context, mm->pgd); 90 } 91 92 #define deactivate_mm(tsk, mm) do { } while (0) 93 94 extern void mmu_context_init(void); 95 #define prepare_arch_switch(next) load_ksp_mmu(next) 96 97 static inline void load_ksp_mmu(struct task_struct *task) 98 { 99 unsigned long flags; 100 struct mm_struct *mm; 101 int asid; 102 pgd_t *pgd; 103 pmd_t *pmd; 104 pte_t *pte; 105 unsigned long mmuar; 106 107 local_irq_save(flags); 108 mmuar = task->thread.ksp; 109 110 /* Search for a valid TLB entry, if one is found, don't remap */ 111 mmu_write(MMUAR, mmuar); 112 mmu_write(MMUOR, MMUOR_STLB | MMUOR_ADR); 113 if (mmu_read(MMUSR) & MMUSR_HIT) 114 goto end; 115 116 if (mmuar >= PAGE_OFFSET) { 117 mm = &init_mm; 118 } else { 119 pr_info("load_ksp_mmu: non-kernel mm found: 0x%p\n", task->mm); 120 mm = task->mm; 121 } 122 123 if (!mm) 124 goto bug; 125 126 pgd = pgd_offset(mm, mmuar); 127 if (pgd_none(*pgd)) 128 goto bug; 129 130 pmd = pmd_offset(pgd, mmuar); 131 if (pmd_none(*pmd)) 132 goto bug; 133 134 pte = (mmuar >= PAGE_OFFSET) ? pte_offset_kernel(pmd, mmuar) 135 : pte_offset_map(pmd, mmuar); 136 if (pte_none(*pte) || !pte_present(*pte)) 137 goto bug; 138 139 set_pte(pte, pte_mkyoung(*pte)); 140 asid = mm->context & 0xff; 141 if (!pte_dirty(*pte) && mmuar <= PAGE_OFFSET) 142 set_pte(pte, pte_wrprotect(*pte)); 143 144 mmu_write(MMUTR, (mmuar & PAGE_MASK) | (asid << MMUTR_IDN) | 145 (((int)(pte->pte) & (int)CF_PAGE_MMUTR_MASK) 146 >> CF_PAGE_MMUTR_SHIFT) | MMUTR_V); 147 148 mmu_write(MMUDR, (pte_val(*pte) & PAGE_MASK) | 149 ((pte->pte) & CF_PAGE_MMUDR_MASK) | MMUDR_SZ_8KB | MMUDR_X); 150 151 mmu_write(MMUOR, MMUOR_ACC | MMUOR_UAA); 152 153 goto end; 154 155 bug: 156 pr_info("ksp load failed: mm=0x%p ksp=0x08%lx\n", mm, mmuar); 157 end: 158 local_irq_restore(flags); 159 } 160 161 #elif defined(CONFIG_SUN3) 162 #include <asm/sun3mmu.h> 163 #include <linux/sched.h> 164 165 extern unsigned long get_free_context(struct mm_struct *mm); 166 extern void clear_context(unsigned long context); 167 168 /* set the context for a new task to unmapped */ 169 static inline int init_new_context(struct task_struct *tsk, 170 struct mm_struct *mm) 171 { 172 mm->context = SUN3_INVALID_CONTEXT; 173 return 0; 174 } 175 176 /* find the context given to this process, and if it hasn't already 177 got one, go get one for it. */ 178 static inline void get_mmu_context(struct mm_struct *mm) 179 { 180 if (mm->context == SUN3_INVALID_CONTEXT) 181 mm->context = get_free_context(mm); 182 } 183 184 /* flush context if allocated... */ 185 static inline void destroy_context(struct mm_struct *mm) 186 { 187 if (mm->context != SUN3_INVALID_CONTEXT) 188 clear_context(mm->context); 189 } 190 191 static inline void activate_context(struct mm_struct *mm) 192 { 193 get_mmu_context(mm); 194 sun3_put_context(mm->context); 195 } 196 197 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, 198 struct task_struct *tsk) 199 { 200 activate_context(tsk->mm); 201 } 202 203 #define deactivate_mm(tsk, mm) do { } while (0) 204 205 static inline void activate_mm(struct mm_struct *prev_mm, 206 struct mm_struct *next_mm) 207 { 208 activate_context(next_mm); 209 } 210 211 #else 212 213 #include <asm/setup.h> 214 #include <asm/page.h> 215 #include <asm/pgalloc.h> 216 217 static inline int init_new_context(struct task_struct *tsk, 218 struct mm_struct *mm) 219 { 220 mm->context = virt_to_phys(mm->pgd); 221 return 0; 222 } 223 224 #define destroy_context(mm) do { } while(0) 225 226 static inline void switch_mm_0230(struct mm_struct *mm) 227 { 228 unsigned long crp[2] = { 229 0x80000000 | _PAGE_TABLE, mm->context 230 }; 231 unsigned long tmp; 232 233 asm volatile (".chip 68030"); 234 235 /* flush MC68030/MC68020 caches (they are virtually addressed) */ 236 asm volatile ( 237 "movec %%cacr,%0;" 238 "orw %1,%0; " 239 "movec %0,%%cacr" 240 : "=d" (tmp) : "di" (FLUSH_I_AND_D)); 241 242 /* Switch the root pointer. For a 030-only kernel, 243 * avoid flushing the whole ATC, we only need to 244 * flush the user entries. The 68851 does this by 245 * itself. Avoid a runtime check here. 246 */ 247 asm volatile ( 248 #ifdef CPU_M68030_ONLY 249 "pmovefd %0,%%crp; " 250 "pflush #0,#4" 251 #else 252 "pmove %0,%%crp" 253 #endif 254 : : "m" (crp[0])); 255 256 asm volatile (".chip 68k"); 257 } 258 259 static inline void switch_mm_0460(struct mm_struct *mm) 260 { 261 asm volatile (".chip 68040"); 262 263 /* flush address translation cache (user entries) */ 264 asm volatile ("pflushan"); 265 266 /* switch the root pointer */ 267 asm volatile ("movec %0,%%urp" : : "r" (mm->context)); 268 269 if (CPU_IS_060) { 270 unsigned long tmp; 271 272 /* clear user entries in the branch cache */ 273 asm volatile ( 274 "movec %%cacr,%0; " 275 "orl %1,%0; " 276 "movec %0,%%cacr" 277 : "=d" (tmp): "di" (0x00200000)); 278 } 279 280 asm volatile (".chip 68k"); 281 } 282 283 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, struct task_struct *tsk) 284 { 285 if (prev != next) { 286 if (CPU_IS_020_OR_030) 287 switch_mm_0230(next); 288 else 289 switch_mm_0460(next); 290 } 291 } 292 293 #define deactivate_mm(tsk,mm) do { } while (0) 294 295 static inline void activate_mm(struct mm_struct *prev_mm, 296 struct mm_struct *next_mm) 297 { 298 next_mm->context = virt_to_phys(next_mm->pgd); 299 300 if (CPU_IS_020_OR_030) 301 switch_mm_0230(next_mm); 302 else 303 switch_mm_0460(next_mm); 304 } 305 306 #endif 307 308 #else /* !CONFIG_MMU */ 309 310 static inline int init_new_context(struct task_struct *tsk, struct mm_struct *mm) 311 { 312 return 0; 313 } 314 315 316 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, struct task_struct *tsk) 317 { 318 } 319 320 #define destroy_context(mm) do { } while (0) 321 #define deactivate_mm(tsk,mm) do { } while (0) 322 323 static inline void activate_mm(struct mm_struct *prev_mm, struct mm_struct *next_mm) 324 { 325 } 326 327 #endif /* CONFIG_MMU */ 328 #endif /* __M68K_MMU_CONTEXT_H */ 329