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/elf.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 stmfd sp!, {lr} 75 mov ip, #PSR_F_BIT | PSR_I_BIT | SVC_MODE 76 msr cpsr_c, ip 77#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH 78 bl arm922_flush_kern_cache_all 79#else 80 bl v4wt_flush_kern_cache_all 81#endif 82 mrc p15, 0, r0, c1, c0, 0 @ ctrl register 83 bic r0, r0, #0x1000 @ ...i............ 84 bic r0, r0, #0x000e @ ............wca. 85 mcr p15, 0, r0, c1, c0, 0 @ disable caches 86 ldmfd sp!, {pc} 87 88/* 89 * cpu_arm922_reset(loc) 90 * 91 * Perform a soft reset of the system. Put the CPU into the 92 * same state as it would be if it had been reset, and branch 93 * to what would be the reset vector. 94 * 95 * loc: location to jump to for soft reset 96 */ 97 .align 5 98ENTRY(cpu_arm922_reset) 99 mov ip, #0 100 mcr p15, 0, ip, c7, c7, 0 @ invalidate I,D caches 101 mcr p15, 0, ip, c7, c10, 4 @ drain WB 102#ifdef CONFIG_MMU 103 mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs 104#endif 105 mrc p15, 0, ip, c1, c0, 0 @ ctrl register 106 bic ip, ip, #0x000f @ ............wcam 107 bic ip, ip, #0x1100 @ ...i...s........ 108 mcr p15, 0, ip, c1, c0, 0 @ ctrl register 109 mov pc, r0 110 111/* 112 * cpu_arm922_do_idle() 113 */ 114 .align 5 115ENTRY(cpu_arm922_do_idle) 116 mcr p15, 0, r0, c7, c0, 4 @ Wait for interrupt 117 mov pc, lr 118 119 120#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH 121 122/* 123 * flush_user_cache_all() 124 * 125 * Clean and invalidate all cache entries in a particular 126 * address space. 127 */ 128ENTRY(arm922_flush_user_cache_all) 129 /* FALLTHROUGH */ 130 131/* 132 * flush_kern_cache_all() 133 * 134 * Clean and invalidate the entire cache. 135 */ 136ENTRY(arm922_flush_kern_cache_all) 137 mov r2, #VM_EXEC 138 mov ip, #0 139__flush_whole_cache: 140 mov r1, #(CACHE_DSEGMENTS - 1) << 5 @ 8 segments 1411: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries 1422: mcr p15, 0, r3, c7, c14, 2 @ clean+invalidate D index 143 subs r3, r3, #1 << 26 144 bcs 2b @ entries 63 to 0 145 subs r1, r1, #1 << 5 146 bcs 1b @ segments 7 to 0 147 tst r2, #VM_EXEC 148 mcrne p15, 0, ip, c7, c5, 0 @ invalidate I cache 149 mcrne p15, 0, ip, c7, c10, 4 @ drain WB 150 mov pc, lr 151 152/* 153 * flush_user_cache_range(start, end, flags) 154 * 155 * Clean and invalidate a range of cache entries in the 156 * specified address range. 157 * 158 * - start - start address (inclusive) 159 * - end - end address (exclusive) 160 * - flags - vm_flags describing address space 161 */ 162ENTRY(arm922_flush_user_cache_range) 163 mov ip, #0 164 sub r3, r1, r0 @ calculate total size 165 cmp r3, #CACHE_DLIMIT 166 bhs __flush_whole_cache 167 1681: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry 169 tst r2, #VM_EXEC 170 mcrne p15, 0, r0, c7, c5, 1 @ invalidate I entry 171 add r0, r0, #CACHE_DLINESIZE 172 cmp r0, r1 173 blo 1b 174 tst r2, #VM_EXEC 175 mcrne p15, 0, ip, c7, c10, 4 @ drain WB 176 mov pc, lr 177 178/* 179 * coherent_kern_range(start, end) 180 * 181 * Ensure coherency between the Icache and the Dcache in the 182 * region described by start, end. If you have non-snooping 183 * Harvard caches, you need to implement this function. 184 * 185 * - start - virtual start address 186 * - end - virtual end address 187 */ 188ENTRY(arm922_coherent_kern_range) 189 /* FALLTHROUGH */ 190 191/* 192 * coherent_user_range(start, end) 193 * 194 * Ensure coherency between the Icache and the Dcache in the 195 * region described by start, end. If you have non-snooping 196 * Harvard caches, you need to implement this function. 197 * 198 * - start - virtual start address 199 * - end - virtual end address 200 */ 201ENTRY(arm922_coherent_user_range) 202 bic r0, r0, #CACHE_DLINESIZE - 1 2031: mcr p15, 0, r0, c7, c10, 1 @ clean D entry 204 mcr p15, 0, r0, c7, c5, 1 @ invalidate I entry 205 add r0, r0, #CACHE_DLINESIZE 206 cmp r0, r1 207 blo 1b 208 mcr p15, 0, r0, c7, c10, 4 @ drain WB 209 mov pc, lr 210 211/* 212 * flush_kern_dcache_page(void *page) 213 * 214 * Ensure no D cache aliasing occurs, either with itself or 215 * the I cache 216 * 217 * - addr - page aligned address 218 */ 219ENTRY(arm922_flush_kern_dcache_page) 220 add r1, r0, #PAGE_SZ 2211: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry 222 add r0, r0, #CACHE_DLINESIZE 223 cmp r0, r1 224 blo 1b 225 mov r0, #0 226 mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache 227 mcr p15, 0, r0, c7, c10, 4 @ drain WB 228 mov pc, lr 229 230/* 231 * dma_inv_range(start, end) 232 * 233 * Invalidate (discard) the specified virtual address range. 234 * May not write back any entries. If 'start' or 'end' 235 * are not cache line aligned, those lines must be written 236 * back. 237 * 238 * - start - virtual start address 239 * - end - virtual end address 240 * 241 * (same as v4wb) 242 */ 243ENTRY(arm922_dma_inv_range) 244 tst r0, #CACHE_DLINESIZE - 1 245 bic r0, r0, #CACHE_DLINESIZE - 1 246 mcrne p15, 0, r0, c7, c10, 1 @ clean D entry 247 tst r1, #CACHE_DLINESIZE - 1 248 mcrne p15, 0, r1, c7, c10, 1 @ clean D entry 2491: mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry 250 add r0, r0, #CACHE_DLINESIZE 251 cmp r0, r1 252 blo 1b 253 mcr p15, 0, r0, c7, c10, 4 @ drain WB 254 mov pc, lr 255 256/* 257 * dma_clean_range(start, end) 258 * 259 * Clean the specified virtual address range. 260 * 261 * - start - virtual start address 262 * - end - virtual end address 263 * 264 * (same as v4wb) 265 */ 266ENTRY(arm922_dma_clean_range) 267 bic r0, r0, #CACHE_DLINESIZE - 1 2681: mcr p15, 0, r0, c7, c10, 1 @ clean D entry 269 add r0, r0, #CACHE_DLINESIZE 270 cmp r0, r1 271 blo 1b 272 mcr p15, 0, r0, c7, c10, 4 @ drain WB 273 mov pc, lr 274 275/* 276 * dma_flush_range(start, end) 277 * 278 * Clean and invalidate the specified virtual address range. 279 * 280 * - start - virtual start address 281 * - end - virtual end address 282 */ 283ENTRY(arm922_dma_flush_range) 284 bic r0, r0, #CACHE_DLINESIZE - 1 2851: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry 286 add r0, r0, #CACHE_DLINESIZE 287 cmp r0, r1 288 blo 1b 289 mcr p15, 0, r0, c7, c10, 4 @ drain WB 290 mov pc, lr 291 292ENTRY(arm922_cache_fns) 293 .long arm922_flush_kern_cache_all 294 .long arm922_flush_user_cache_all 295 .long arm922_flush_user_cache_range 296 .long arm922_coherent_kern_range 297 .long arm922_coherent_user_range 298 .long arm922_flush_kern_dcache_page 299 .long arm922_dma_inv_range 300 .long arm922_dma_clean_range 301 .long arm922_dma_flush_range 302 303#endif 304 305 306ENTRY(cpu_arm922_dcache_clean_area) 307#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH 3081: mcr p15, 0, r0, c7, c10, 1 @ clean D entry 309 add r0, r0, #CACHE_DLINESIZE 310 subs r1, r1, #CACHE_DLINESIZE 311 bhi 1b 312#endif 313 mov pc, lr 314 315/* =============================== PageTable ============================== */ 316 317/* 318 * cpu_arm922_switch_mm(pgd) 319 * 320 * Set the translation base pointer to be as described by pgd. 321 * 322 * pgd: new page tables 323 */ 324 .align 5 325ENTRY(cpu_arm922_switch_mm) 326#ifdef CONFIG_MMU 327 mov ip, #0 328#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH 329 mcr p15, 0, ip, c7, c6, 0 @ invalidate D cache 330#else 331@ && 'Clean & Invalidate whole DCache' 332@ && Re-written to use Index Ops. 333@ && Uses registers r1, r3 and ip 334 335 mov r1, #(CACHE_DSEGMENTS - 1) << 5 @ 4 segments 3361: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries 3372: mcr p15, 0, r3, c7, c14, 2 @ clean & invalidate D index 338 subs r3, r3, #1 << 26 339 bcs 2b @ entries 63 to 0 340 subs r1, r1, #1 << 5 341 bcs 1b @ segments 7 to 0 342#endif 343 mcr p15, 0, ip, c7, c5, 0 @ invalidate I cache 344 mcr p15, 0, ip, c7, c10, 4 @ drain WB 345 mcr p15, 0, r0, c2, c0, 0 @ load page table pointer 346 mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs 347#endif 348 mov pc, lr 349 350/* 351 * cpu_arm922_set_pte_ext(ptep, pte, ext) 352 * 353 * Set a PTE and flush it out 354 */ 355 .align 5 356ENTRY(cpu_arm922_set_pte_ext) 357#ifdef CONFIG_MMU 358 str r1, [r0], #-2048 @ linux version 359 360 eor r1, r1, #L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_WRITE | L_PTE_DIRTY 361 362 bic r2, r1, #PTE_SMALL_AP_MASK 363 bic r2, r2, #PTE_TYPE_MASK 364 orr r2, r2, #PTE_TYPE_SMALL 365 366 tst r1, #L_PTE_USER @ User? 367 orrne r2, r2, #PTE_SMALL_AP_URO_SRW 368 369 tst r1, #L_PTE_WRITE | L_PTE_DIRTY @ Write and Dirty? 370 orreq r2, r2, #PTE_SMALL_AP_UNO_SRW 371 372 tst r1, #L_PTE_PRESENT | L_PTE_YOUNG @ Present and Young? 373 movne r2, #0 374 375#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH 376 eor r3, r2, #0x0a @ C & small page? 377 tst r3, #0x0b 378 biceq r2, r2, #4 379#endif 380 str r2, [r0] @ hardware version 381 mov r0, r0 382 mcr p15, 0, r0, c7, c10, 1 @ clean D entry 383 mcr p15, 0, r0, c7, c10, 4 @ drain WB 384#endif /* CONFIG_MMU */ 385 mov pc, lr 386 387 __INIT 388 389 .type __arm922_setup, #function 390__arm922_setup: 391 mov r0, #0 392 mcr p15, 0, r0, c7, c7 @ invalidate I,D caches on v4 393 mcr p15, 0, r0, c7, c10, 4 @ drain write buffer on v4 394#ifdef CONFIG_MMU 395 mcr p15, 0, r0, c8, c7 @ invalidate I,D TLBs on v4 396#endif 397 adr r5, arm922_crval 398 ldmia r5, {r5, r6} 399 mrc p15, 0, r0, c1, c0 @ get control register v4 400 bic r0, r0, r5 401 orr r0, r0, r6 402 mov pc, lr 403 .size __arm922_setup, . - __arm922_setup 404 405 /* 406 * R 407 * .RVI ZFRS BLDP WCAM 408 * ..11 0001 ..11 0101 409 * 410 */ 411 .type arm922_crval, #object 412arm922_crval: 413 crval clear=0x00003f3f, mmuset=0x00003135, ucset=0x00001130 414 415 __INITDATA 416 417/* 418 * Purpose : Function pointers used to access above functions - all calls 419 * come through these 420 */ 421 .type arm922_processor_functions, #object 422arm922_processor_functions: 423 .word v4t_early_abort 424 .word pabort_noifar 425 .word cpu_arm922_proc_init 426 .word cpu_arm922_proc_fin 427 .word cpu_arm922_reset 428 .word cpu_arm922_do_idle 429 .word cpu_arm922_dcache_clean_area 430 .word cpu_arm922_switch_mm 431 .word cpu_arm922_set_pte_ext 432 .size arm922_processor_functions, . - arm922_processor_functions 433 434 .section ".rodata" 435 436 .type cpu_arch_name, #object 437cpu_arch_name: 438 .asciz "armv4t" 439 .size cpu_arch_name, . - cpu_arch_name 440 441 .type cpu_elf_name, #object 442cpu_elf_name: 443 .asciz "v4" 444 .size cpu_elf_name, . - cpu_elf_name 445 446 .type cpu_arm922_name, #object 447cpu_arm922_name: 448 .asciz "ARM922T" 449 .size cpu_arm922_name, . - cpu_arm922_name 450 451 .align 452 453 .section ".proc.info.init", #alloc, #execinstr 454 455 .type __arm922_proc_info,#object 456__arm922_proc_info: 457 .long 0x41009220 458 .long 0xff00fff0 459 .long PMD_TYPE_SECT | \ 460 PMD_SECT_BUFFERABLE | \ 461 PMD_SECT_CACHEABLE | \ 462 PMD_BIT4 | \ 463 PMD_SECT_AP_WRITE | \ 464 PMD_SECT_AP_READ 465 .long PMD_TYPE_SECT | \ 466 PMD_BIT4 | \ 467 PMD_SECT_AP_WRITE | \ 468 PMD_SECT_AP_READ 469 b __arm922_setup 470 .long cpu_arch_name 471 .long cpu_elf_name 472 .long HWCAP_SWP | HWCAP_HALF | HWCAP_THUMB 473 .long cpu_arm922_name 474 .long arm922_processor_functions 475 .long v4wbi_tlb_fns 476 .long v4wb_user_fns 477#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH 478 .long arm922_cache_fns 479#else 480 .long v4wt_cache_fns 481#endif 482 .size __arm922_proc_info, . - __arm922_proc_info 483