1/* 2 * linux/arch/arm/mm/proc-arm922.S: MMU functions for ARM922 3 * 4 * Copyright (C) 1999,2000 ARM Limited 5 * Copyright (C) 2000 Deep Blue Solutions Ltd. 6 * Copyright (C) 2001 Altera Corporation 7 * hacked for non-paged-MM by Hyok S. Choi, 2003. 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License as published by 11 * the Free Software Foundation; either version 2 of the License, or 12 * (at your option) any later version. 13 * 14 * This program is distributed in the hope that it will be useful, 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 * GNU General Public License for more details. 18 * 19 * You should have received a copy of the GNU General Public License 20 * along with this program; if not, write to the Free Software 21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 22 * 23 * 24 * These are the low level assembler for performing cache and TLB 25 * functions on the arm922. 26 * 27 * CONFIG_CPU_ARM922_CPU_IDLE -> nohlt 28 */ 29#include <linux/linkage.h> 30#include <linux/init.h> 31#include <asm/assembler.h> 32#include <asm/hwcap.h> 33#include <asm/pgtable-hwdef.h> 34#include <asm/pgtable.h> 35#include <asm/page.h> 36#include <asm/ptrace.h> 37#include "proc-macros.S" 38 39/* 40 * The size of one data cache line. 41 */ 42#define CACHE_DLINESIZE 32 43 44/* 45 * The number of data cache segments. 46 */ 47#define CACHE_DSEGMENTS 4 48 49/* 50 * The number of lines in a cache segment. 51 */ 52#define CACHE_DENTRIES 64 53 54/* 55 * This is the size at which it becomes more efficient to 56 * clean the whole cache, rather than using the individual 57 * cache line maintainence instructions. (I think this should 58 * be 32768). 59 */ 60#define CACHE_DLIMIT 8192 61 62 63 .text 64/* 65 * cpu_arm922_proc_init() 66 */ 67ENTRY(cpu_arm922_proc_init) 68 mov pc, lr 69 70/* 71 * cpu_arm922_proc_fin() 72 */ 73ENTRY(cpu_arm922_proc_fin) 74 mrc p15, 0, r0, c1, c0, 0 @ ctrl register 75 bic r0, r0, #0x1000 @ ...i............ 76 bic r0, r0, #0x000e @ ............wca. 77 mcr p15, 0, r0, c1, c0, 0 @ disable caches 78 mov pc, lr 79 80/* 81 * cpu_arm922_reset(loc) 82 * 83 * Perform a soft reset of the system. Put the CPU into the 84 * same state as it would be if it had been reset, and branch 85 * to what would be the reset vector. 86 * 87 * loc: location to jump to for soft reset 88 */ 89 .align 5 90ENTRY(cpu_arm922_reset) 91 mov ip, #0 92 mcr p15, 0, ip, c7, c7, 0 @ invalidate I,D caches 93 mcr p15, 0, ip, c7, c10, 4 @ drain WB 94#ifdef CONFIG_MMU 95 mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs 96#endif 97 mrc p15, 0, ip, c1, c0, 0 @ ctrl register 98 bic ip, ip, #0x000f @ ............wcam 99 bic ip, ip, #0x1100 @ ...i...s........ 100 mcr p15, 0, ip, c1, c0, 0 @ ctrl register 101 mov pc, r0 102 103/* 104 * cpu_arm922_do_idle() 105 */ 106 .align 5 107ENTRY(cpu_arm922_do_idle) 108 mcr p15, 0, r0, c7, c0, 4 @ Wait for interrupt 109 mov pc, lr 110 111 112#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH 113 114/* 115 * flush_icache_all() 116 * 117 * Unconditionally clean and invalidate the entire icache. 118 */ 119ENTRY(arm922_flush_icache_all) 120 mov r0, #0 121 mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache 122 mov pc, lr 123ENDPROC(arm922_flush_icache_all) 124 125/* 126 * flush_user_cache_all() 127 * 128 * Clean and invalidate all cache entries in a particular 129 * address space. 130 */ 131ENTRY(arm922_flush_user_cache_all) 132 /* FALLTHROUGH */ 133 134/* 135 * flush_kern_cache_all() 136 * 137 * Clean and invalidate the entire cache. 138 */ 139ENTRY(arm922_flush_kern_cache_all) 140 mov r2, #VM_EXEC 141 mov ip, #0 142__flush_whole_cache: 143 mov r1, #(CACHE_DSEGMENTS - 1) << 5 @ 8 segments 1441: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries 1452: mcr p15, 0, r3, c7, c14, 2 @ clean+invalidate D index 146 subs r3, r3, #1 << 26 147 bcs 2b @ entries 63 to 0 148 subs r1, r1, #1 << 5 149 bcs 1b @ segments 7 to 0 150 tst r2, #VM_EXEC 151 mcrne p15, 0, ip, c7, c5, 0 @ invalidate I cache 152 mcrne p15, 0, ip, c7, c10, 4 @ drain WB 153 mov pc, lr 154 155/* 156 * flush_user_cache_range(start, end, flags) 157 * 158 * Clean and invalidate a range of cache entries in the 159 * specified address range. 160 * 161 * - start - start address (inclusive) 162 * - end - end address (exclusive) 163 * - flags - vm_flags describing address space 164 */ 165ENTRY(arm922_flush_user_cache_range) 166 mov ip, #0 167 sub r3, r1, r0 @ calculate total size 168 cmp r3, #CACHE_DLIMIT 169 bhs __flush_whole_cache 170 1711: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry 172 tst r2, #VM_EXEC 173 mcrne p15, 0, r0, c7, c5, 1 @ invalidate I entry 174 add r0, r0, #CACHE_DLINESIZE 175 cmp r0, r1 176 blo 1b 177 tst r2, #VM_EXEC 178 mcrne p15, 0, ip, c7, c10, 4 @ drain WB 179 mov pc, lr 180 181/* 182 * coherent_kern_range(start, end) 183 * 184 * Ensure coherency between the Icache and the Dcache in the 185 * region described by start, end. If you have non-snooping 186 * Harvard caches, you need to implement this function. 187 * 188 * - start - virtual start address 189 * - end - virtual end address 190 */ 191ENTRY(arm922_coherent_kern_range) 192 /* FALLTHROUGH */ 193 194/* 195 * coherent_user_range(start, end) 196 * 197 * Ensure coherency between the Icache and the Dcache in the 198 * region described by start, end. If you have non-snooping 199 * Harvard caches, you need to implement this function. 200 * 201 * - start - virtual start address 202 * - end - virtual end address 203 */ 204ENTRY(arm922_coherent_user_range) 205 bic r0, r0, #CACHE_DLINESIZE - 1 2061: mcr p15, 0, r0, c7, c10, 1 @ clean D entry 207 mcr p15, 0, r0, c7, c5, 1 @ invalidate I entry 208 add r0, r0, #CACHE_DLINESIZE 209 cmp r0, r1 210 blo 1b 211 mcr p15, 0, r0, c7, c10, 4 @ drain WB 212 mov pc, lr 213 214/* 215 * flush_kern_dcache_area(void *addr, size_t size) 216 * 217 * Ensure no D cache aliasing occurs, either with itself or 218 * the I cache 219 * 220 * - addr - kernel address 221 * - size - region size 222 */ 223ENTRY(arm922_flush_kern_dcache_area) 224 add r1, r0, r1 2251: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry 226 add r0, r0, #CACHE_DLINESIZE 227 cmp r0, r1 228 blo 1b 229 mov r0, #0 230 mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache 231 mcr p15, 0, r0, c7, c10, 4 @ drain WB 232 mov pc, lr 233 234/* 235 * dma_inv_range(start, end) 236 * 237 * Invalidate (discard) the specified virtual address range. 238 * May not write back any entries. If 'start' or 'end' 239 * are not cache line aligned, those lines must be written 240 * back. 241 * 242 * - start - virtual start address 243 * - end - virtual end address 244 * 245 * (same as v4wb) 246 */ 247arm922_dma_inv_range: 248 tst r0, #CACHE_DLINESIZE - 1 249 bic r0, r0, #CACHE_DLINESIZE - 1 250 mcrne p15, 0, r0, c7, c10, 1 @ clean D entry 251 tst r1, #CACHE_DLINESIZE - 1 252 mcrne p15, 0, r1, c7, c10, 1 @ clean D entry 2531: mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry 254 add r0, r0, #CACHE_DLINESIZE 255 cmp r0, r1 256 blo 1b 257 mcr p15, 0, r0, c7, c10, 4 @ drain WB 258 mov pc, lr 259 260/* 261 * dma_clean_range(start, end) 262 * 263 * Clean the specified virtual address range. 264 * 265 * - start - virtual start address 266 * - end - virtual end address 267 * 268 * (same as v4wb) 269 */ 270arm922_dma_clean_range: 271 bic r0, r0, #CACHE_DLINESIZE - 1 2721: mcr p15, 0, r0, c7, c10, 1 @ clean D entry 273 add r0, r0, #CACHE_DLINESIZE 274 cmp r0, r1 275 blo 1b 276 mcr p15, 0, r0, c7, c10, 4 @ drain WB 277 mov pc, lr 278 279/* 280 * dma_flush_range(start, end) 281 * 282 * Clean and invalidate the specified virtual address range. 283 * 284 * - start - virtual start address 285 * - end - virtual end address 286 */ 287ENTRY(arm922_dma_flush_range) 288 bic r0, r0, #CACHE_DLINESIZE - 1 2891: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry 290 add r0, r0, #CACHE_DLINESIZE 291 cmp r0, r1 292 blo 1b 293 mcr p15, 0, r0, c7, c10, 4 @ drain WB 294 mov pc, lr 295 296/* 297 * dma_map_area(start, size, dir) 298 * - start - kernel virtual start address 299 * - size - size of region 300 * - dir - DMA direction 301 */ 302ENTRY(arm922_dma_map_area) 303 add r1, r1, r0 304 cmp r2, #DMA_TO_DEVICE 305 beq arm922_dma_clean_range 306 bcs arm922_dma_inv_range 307 b arm922_dma_flush_range 308ENDPROC(arm922_dma_map_area) 309 310/* 311 * dma_unmap_area(start, size, dir) 312 * - start - kernel virtual start address 313 * - size - size of region 314 * - dir - DMA direction 315 */ 316ENTRY(arm922_dma_unmap_area) 317 mov pc, lr 318ENDPROC(arm922_dma_unmap_area) 319 320ENTRY(arm922_cache_fns) 321 .long arm922_flush_icache_all 322 .long arm922_flush_kern_cache_all 323 .long arm922_flush_user_cache_all 324 .long arm922_flush_user_cache_range 325 .long arm922_coherent_kern_range 326 .long arm922_coherent_user_range 327 .long arm922_flush_kern_dcache_area 328 .long arm922_dma_map_area 329 .long arm922_dma_unmap_area 330 .long arm922_dma_flush_range 331 332#endif 333 334 335ENTRY(cpu_arm922_dcache_clean_area) 336#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH 3371: mcr p15, 0, r0, c7, c10, 1 @ clean D entry 338 add r0, r0, #CACHE_DLINESIZE 339 subs r1, r1, #CACHE_DLINESIZE 340 bhi 1b 341#endif 342 mov pc, lr 343 344/* =============================== PageTable ============================== */ 345 346/* 347 * cpu_arm922_switch_mm(pgd) 348 * 349 * Set the translation base pointer to be as described by pgd. 350 * 351 * pgd: new page tables 352 */ 353 .align 5 354ENTRY(cpu_arm922_switch_mm) 355#ifdef CONFIG_MMU 356 mov ip, #0 357#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH 358 mcr p15, 0, ip, c7, c6, 0 @ invalidate D cache 359#else 360@ && 'Clean & Invalidate whole DCache' 361@ && Re-written to use Index Ops. 362@ && Uses registers r1, r3 and ip 363 364 mov r1, #(CACHE_DSEGMENTS - 1) << 5 @ 4 segments 3651: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries 3662: mcr p15, 0, r3, c7, c14, 2 @ clean & invalidate D index 367 subs r3, r3, #1 << 26 368 bcs 2b @ entries 63 to 0 369 subs r1, r1, #1 << 5 370 bcs 1b @ segments 7 to 0 371#endif 372 mcr p15, 0, ip, c7, c5, 0 @ invalidate I cache 373 mcr p15, 0, ip, c7, c10, 4 @ drain WB 374 mcr p15, 0, r0, c2, c0, 0 @ load page table pointer 375 mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs 376#endif 377 mov pc, lr 378 379/* 380 * cpu_arm922_set_pte_ext(ptep, pte, ext) 381 * 382 * Set a PTE and flush it out 383 */ 384 .align 5 385ENTRY(cpu_arm922_set_pte_ext) 386#ifdef CONFIG_MMU 387 armv3_set_pte_ext 388 mov r0, r0 389 mcr p15, 0, r0, c7, c10, 1 @ clean D entry 390 mcr p15, 0, r0, c7, c10, 4 @ drain WB 391#endif /* CONFIG_MMU */ 392 mov pc, lr 393 394 __CPUINIT 395 396 .type __arm922_setup, #function 397__arm922_setup: 398 mov r0, #0 399 mcr p15, 0, r0, c7, c7 @ invalidate I,D caches on v4 400 mcr p15, 0, r0, c7, c10, 4 @ drain write buffer on v4 401#ifdef CONFIG_MMU 402 mcr p15, 0, r0, c8, c7 @ invalidate I,D TLBs on v4 403#endif 404 adr r5, arm922_crval 405 ldmia r5, {r5, r6} 406 mrc p15, 0, r0, c1, c0 @ get control register v4 407 bic r0, r0, r5 408 orr r0, r0, r6 409 mov pc, lr 410 .size __arm922_setup, . - __arm922_setup 411 412 /* 413 * R 414 * .RVI ZFRS BLDP WCAM 415 * ..11 0001 ..11 0101 416 * 417 */ 418 .type arm922_crval, #object 419arm922_crval: 420 crval clear=0x00003f3f, mmuset=0x00003135, ucset=0x00001130 421 422 __INITDATA 423 424/* 425 * Purpose : Function pointers used to access above functions - all calls 426 * come through these 427 */ 428 .type arm922_processor_functions, #object 429arm922_processor_functions: 430 .word v4t_early_abort 431 .word legacy_pabort 432 .word cpu_arm922_proc_init 433 .word cpu_arm922_proc_fin 434 .word cpu_arm922_reset 435 .word cpu_arm922_do_idle 436 .word cpu_arm922_dcache_clean_area 437 .word cpu_arm922_switch_mm 438 .word cpu_arm922_set_pte_ext 439 .size arm922_processor_functions, . - arm922_processor_functions 440 441 .section ".rodata" 442 443 .type cpu_arch_name, #object 444cpu_arch_name: 445 .asciz "armv4t" 446 .size cpu_arch_name, . - cpu_arch_name 447 448 .type cpu_elf_name, #object 449cpu_elf_name: 450 .asciz "v4" 451 .size cpu_elf_name, . - cpu_elf_name 452 453 .type cpu_arm922_name, #object 454cpu_arm922_name: 455 .asciz "ARM922T" 456 .size cpu_arm922_name, . - cpu_arm922_name 457 458 .align 459 460 .section ".proc.info.init", #alloc, #execinstr 461 462 .type __arm922_proc_info,#object 463__arm922_proc_info: 464 .long 0x41009220 465 .long 0xff00fff0 466 .long PMD_TYPE_SECT | \ 467 PMD_SECT_BUFFERABLE | \ 468 PMD_SECT_CACHEABLE | \ 469 PMD_BIT4 | \ 470 PMD_SECT_AP_WRITE | \ 471 PMD_SECT_AP_READ 472 .long PMD_TYPE_SECT | \ 473 PMD_BIT4 | \ 474 PMD_SECT_AP_WRITE | \ 475 PMD_SECT_AP_READ 476 b __arm922_setup 477 .long cpu_arch_name 478 .long cpu_elf_name 479 .long HWCAP_SWP | HWCAP_HALF | HWCAP_THUMB 480 .long cpu_arm922_name 481 .long arm922_processor_functions 482 .long v4wbi_tlb_fns 483 .long v4wb_user_fns 484#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH 485 .long arm922_cache_fns 486#else 487 .long v4wt_cache_fns 488#endif 489 .size __arm922_proc_info, . - __arm922_proc_info 490