1/* 2 * linux/arch/arm/mm/cache-v7.S 3 * 4 * Copyright (C) 2001 Deep Blue Solutions Ltd. 5 * Copyright (C) 2005 ARM Ltd. 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 * 11 * This is the "shell" of the ARMv7 processor support. 12 */ 13#include <linux/linkage.h> 14#include <linux/init.h> 15#include <asm/assembler.h> 16#include <asm/errno.h> 17#include <asm/unwind.h> 18#include <asm/hardware/cache-b15-rac.h> 19 20#include "proc-macros.S" 21 22#ifdef CONFIG_CPU_ICACHE_MISMATCH_WORKAROUND 23.globl icache_size 24 .data 25 .align 2 26icache_size: 27 .long 64 28 .text 29#endif 30/* 31 * The secondary kernel init calls v7_flush_dcache_all before it enables 32 * the L1; however, the L1 comes out of reset in an undefined state, so 33 * the clean + invalidate performed by v7_flush_dcache_all causes a bunch 34 * of cache lines with uninitialized data and uninitialized tags to get 35 * written out to memory, which does really unpleasant things to the main 36 * processor. We fix this by performing an invalidate, rather than a 37 * clean + invalidate, before jumping into the kernel. 38 * 39 * This function is cloned from arch/arm/mach-tegra/headsmp.S, and needs 40 * to be called for both secondary cores startup and primary core resume 41 * procedures. 42 */ 43ENTRY(v7_invalidate_l1) 44 mov r0, #0 45 mcr p15, 2, r0, c0, c0, 0 46 mrc p15, 1, r0, c0, c0, 0 47 48 movw r1, #0x7fff 49 and r2, r1, r0, lsr #13 50 51 movw r1, #0x3ff 52 53 and r3, r1, r0, lsr #3 @ NumWays - 1 54 add r2, r2, #1 @ NumSets 55 56 and r0, r0, #0x7 57 add r0, r0, #4 @ SetShift 58 59 clz r1, r3 @ WayShift 60 add r4, r3, #1 @ NumWays 611: sub r2, r2, #1 @ NumSets-- 62 mov r3, r4 @ Temp = NumWays 632: subs r3, r3, #1 @ Temp-- 64 mov r5, r3, lsl r1 65 mov r6, r2, lsl r0 66 orr r5, r5, r6 @ Reg = (Temp<<WayShift)|(NumSets<<SetShift) 67 mcr p15, 0, r5, c7, c6, 2 68 bgt 2b 69 cmp r2, #0 70 bgt 1b 71 dsb st 72 isb 73 ret lr 74ENDPROC(v7_invalidate_l1) 75 76/* 77 * v7_flush_icache_all() 78 * 79 * Flush the whole I-cache. 80 * 81 * Registers: 82 * r0 - set to 0 83 */ 84ENTRY(v7_flush_icache_all) 85 mov r0, #0 86 ALT_SMP(mcr p15, 0, r0, c7, c1, 0) @ invalidate I-cache inner shareable 87 ALT_UP(mcr p15, 0, r0, c7, c5, 0) @ I+BTB cache invalidate 88 ret lr 89ENDPROC(v7_flush_icache_all) 90 91 /* 92 * v7_flush_dcache_louis() 93 * 94 * Flush the D-cache up to the Level of Unification Inner Shareable 95 * 96 * Corrupted registers: r0-r7, r9-r11 (r6 only in Thumb mode) 97 */ 98 99ENTRY(v7_flush_dcache_louis) 100 dmb @ ensure ordering with previous memory accesses 101 mrc p15, 1, r0, c0, c0, 1 @ read clidr, r0 = clidr 102ALT_SMP(mov r3, r0, lsr #20) @ move LoUIS into position 103ALT_UP( mov r3, r0, lsr #26) @ move LoUU into position 104 ands r3, r3, #7 << 1 @ extract LoU*2 field from clidr 105 bne start_flush_levels @ LoU != 0, start flushing 106#ifdef CONFIG_ARM_ERRATA_643719 107ALT_SMP(mrc p15, 0, r2, c0, c0, 0) @ read main ID register 108ALT_UP( ret lr) @ LoUU is zero, so nothing to do 109 movw r1, #:lower16:(0x410fc090 >> 4) @ ID of ARM Cortex A9 r0p? 110 movt r1, #:upper16:(0x410fc090 >> 4) 111 teq r1, r2, lsr #4 @ test for errata affected core and if so... 112 moveq r3, #1 << 1 @ fix LoUIS value 113 beq start_flush_levels @ start flushing cache levels 114#endif 115 ret lr 116ENDPROC(v7_flush_dcache_louis) 117 118/* 119 * v7_flush_dcache_all() 120 * 121 * Flush the whole D-cache. 122 * 123 * Corrupted registers: r0-r7, r9-r11 (r6 only in Thumb mode) 124 * 125 * - mm - mm_struct describing address space 126 */ 127ENTRY(v7_flush_dcache_all) 128 dmb @ ensure ordering with previous memory accesses 129 mrc p15, 1, r0, c0, c0, 1 @ read clidr 130 mov r3, r0, lsr #23 @ move LoC into position 131 ands r3, r3, #7 << 1 @ extract LoC*2 from clidr 132 beq finished @ if loc is 0, then no need to clean 133start_flush_levels: 134 mov r10, #0 @ start clean at cache level 0 135flush_levels: 136 add r2, r10, r10, lsr #1 @ work out 3x current cache level 137 mov r1, r0, lsr r2 @ extract cache type bits from clidr 138 and r1, r1, #7 @ mask of the bits for current cache only 139 cmp r1, #2 @ see what cache we have at this level 140 blt skip @ skip if no cache, or just i-cache 141#ifdef CONFIG_PREEMPT 142 save_and_disable_irqs_notrace r9 @ make cssr&csidr read atomic 143#endif 144 mcr p15, 2, r10, c0, c0, 0 @ select current cache level in cssr 145 isb @ isb to sych the new cssr&csidr 146 mrc p15, 1, r1, c0, c0, 0 @ read the new csidr 147#ifdef CONFIG_PREEMPT 148 restore_irqs_notrace r9 149#endif 150 and r2, r1, #7 @ extract the length of the cache lines 151 add r2, r2, #4 @ add 4 (line length offset) 152 movw r4, #0x3ff 153 ands r4, r4, r1, lsr #3 @ find maximum number on the way size 154 clz r5, r4 @ find bit position of way size increment 155 movw r7, #0x7fff 156 ands r7, r7, r1, lsr #13 @ extract max number of the index size 157loop1: 158 mov r9, r7 @ create working copy of max index 159loop2: 160 ARM( orr r11, r10, r4, lsl r5 ) @ factor way and cache number into r11 161 THUMB( lsl r6, r4, r5 ) 162 THUMB( orr r11, r10, r6 ) @ factor way and cache number into r11 163 ARM( orr r11, r11, r9, lsl r2 ) @ factor index number into r11 164 THUMB( lsl r6, r9, r2 ) 165 THUMB( orr r11, r11, r6 ) @ factor index number into r11 166 mcr p15, 0, r11, c7, c14, 2 @ clean & invalidate by set/way 167 subs r9, r9, #1 @ decrement the index 168 bge loop2 169 subs r4, r4, #1 @ decrement the way 170 bge loop1 171skip: 172 add r10, r10, #2 @ increment cache number 173 cmp r3, r10 174 bgt flush_levels 175finished: 176 mov r10, #0 @ switch back to cache level 0 177 mcr p15, 2, r10, c0, c0, 0 @ select current cache level in cssr 178 dsb st 179 isb 180 ret lr 181ENDPROC(v7_flush_dcache_all) 182 183/* 184 * v7_flush_cache_all() 185 * 186 * Flush the entire cache system. 187 * The data cache flush is now achieved using atomic clean / invalidates 188 * working outwards from L1 cache. This is done using Set/Way based cache 189 * maintenance instructions. 190 * The instruction cache can still be invalidated back to the point of 191 * unification in a single instruction. 192 * 193 */ 194ENTRY(v7_flush_kern_cache_all) 195 ARM( stmfd sp!, {r4-r5, r7, r9-r11, lr} ) 196 THUMB( stmfd sp!, {r4-r7, r9-r11, lr} ) 197 bl v7_flush_dcache_all 198 mov r0, #0 199 ALT_SMP(mcr p15, 0, r0, c7, c1, 0) @ invalidate I-cache inner shareable 200 ALT_UP(mcr p15, 0, r0, c7, c5, 0) @ I+BTB cache invalidate 201 ARM( ldmfd sp!, {r4-r5, r7, r9-r11, lr} ) 202 THUMB( ldmfd sp!, {r4-r7, r9-r11, lr} ) 203 ret lr 204ENDPROC(v7_flush_kern_cache_all) 205 206 /* 207 * v7_flush_kern_cache_louis(void) 208 * 209 * Flush the data cache up to Level of Unification Inner Shareable. 210 * Invalidate the I-cache to the point of unification. 211 */ 212ENTRY(v7_flush_kern_cache_louis) 213 ARM( stmfd sp!, {r4-r5, r7, r9-r11, lr} ) 214 THUMB( stmfd sp!, {r4-r7, r9-r11, lr} ) 215 bl v7_flush_dcache_louis 216 mov r0, #0 217 ALT_SMP(mcr p15, 0, r0, c7, c1, 0) @ invalidate I-cache inner shareable 218 ALT_UP(mcr p15, 0, r0, c7, c5, 0) @ I+BTB cache invalidate 219 ARM( ldmfd sp!, {r4-r5, r7, r9-r11, lr} ) 220 THUMB( ldmfd sp!, {r4-r7, r9-r11, lr} ) 221 ret lr 222ENDPROC(v7_flush_kern_cache_louis) 223 224/* 225 * v7_flush_cache_all() 226 * 227 * Flush all TLB entries in a particular address space 228 * 229 * - mm - mm_struct describing address space 230 */ 231ENTRY(v7_flush_user_cache_all) 232 /*FALLTHROUGH*/ 233 234/* 235 * v7_flush_cache_range(start, end, flags) 236 * 237 * Flush a range of TLB entries in the specified address space. 238 * 239 * - start - start address (may not be aligned) 240 * - end - end address (exclusive, may not be aligned) 241 * - flags - vm_area_struct flags describing address space 242 * 243 * It is assumed that: 244 * - we have a VIPT cache. 245 */ 246ENTRY(v7_flush_user_cache_range) 247 ret lr 248ENDPROC(v7_flush_user_cache_all) 249ENDPROC(v7_flush_user_cache_range) 250 251/* 252 * v7_coherent_kern_range(start,end) 253 * 254 * Ensure that the I and D caches are coherent within specified 255 * region. This is typically used when code has been written to 256 * a memory region, and will be executed. 257 * 258 * - start - virtual start address of region 259 * - end - virtual end address of region 260 * 261 * It is assumed that: 262 * - the Icache does not read data from the write buffer 263 */ 264ENTRY(v7_coherent_kern_range) 265 /* FALLTHROUGH */ 266 267/* 268 * v7_coherent_user_range(start,end) 269 * 270 * Ensure that the I and D caches are coherent within specified 271 * region. This is typically used when code has been written to 272 * a memory region, and will be executed. 273 * 274 * - start - virtual start address of region 275 * - end - virtual end address of region 276 * 277 * It is assumed that: 278 * - the Icache does not read data from the write buffer 279 */ 280ENTRY(v7_coherent_user_range) 281 UNWIND(.fnstart ) 282 dcache_line_size r2, r3 283 sub r3, r2, #1 284 bic r12, r0, r3 285#ifdef CONFIG_ARM_ERRATA_764369 286 ALT_SMP(W(dsb)) 287 ALT_UP(W(nop)) 288#endif 2891: 290 USER( mcr p15, 0, r12, c7, c11, 1 ) @ clean D line to the point of unification 291 add r12, r12, r2 292 cmp r12, r1 293 blo 1b 294 dsb ishst 295#ifdef CONFIG_CPU_ICACHE_MISMATCH_WORKAROUND 296 ldr r3, =icache_size 297 ldr r2, [r3, #0] 298#else 299 icache_line_size r2, r3 300#endif 301 sub r3, r2, #1 302 bic r12, r0, r3 3032: 304 USER( mcr p15, 0, r12, c7, c5, 1 ) @ invalidate I line 305 add r12, r12, r2 306 cmp r12, r1 307 blo 2b 308 mov r0, #0 309 ALT_SMP(mcr p15, 0, r0, c7, c1, 6) @ invalidate BTB Inner Shareable 310 ALT_UP(mcr p15, 0, r0, c7, c5, 6) @ invalidate BTB 311 dsb ishst 312 isb 313 ret lr 314 315/* 316 * Fault handling for the cache operation above. If the virtual address in r0 317 * isn't mapped, fail with -EFAULT. 318 */ 3199001: 320#ifdef CONFIG_ARM_ERRATA_775420 321 dsb 322#endif 323 mov r0, #-EFAULT 324 ret lr 325 UNWIND(.fnend ) 326ENDPROC(v7_coherent_kern_range) 327ENDPROC(v7_coherent_user_range) 328 329/* 330 * v7_flush_kern_dcache_area(void *addr, size_t size) 331 * 332 * Ensure that the data held in the page kaddr is written back 333 * to the page in question. 334 * 335 * - addr - kernel address 336 * - size - region size 337 */ 338ENTRY(v7_flush_kern_dcache_area) 339 dcache_line_size r2, r3 340 add r1, r0, r1 341 sub r3, r2, #1 342 bic r0, r0, r3 343#ifdef CONFIG_ARM_ERRATA_764369 344 ALT_SMP(W(dsb)) 345 ALT_UP(W(nop)) 346#endif 3471: 348 mcr p15, 0, r0, c7, c14, 1 @ clean & invalidate D line / unified line 349 add r0, r0, r2 350 cmp r0, r1 351 blo 1b 352 dsb st 353 ret lr 354ENDPROC(v7_flush_kern_dcache_area) 355 356/* 357 * v7_dma_inv_range(start,end) 358 * 359 * Invalidate the data cache within the specified region; we will 360 * be performing a DMA operation in this region and we want to 361 * purge old data in the cache. 362 * 363 * - start - virtual start address of region 364 * - end - virtual end address of region 365 */ 366v7_dma_inv_range: 367 dcache_line_size r2, r3 368 sub r3, r2, #1 369 tst r0, r3 370 bic r0, r0, r3 371#ifdef CONFIG_ARM_ERRATA_764369 372 ALT_SMP(W(dsb)) 373 ALT_UP(W(nop)) 374#endif 375 mcrne p15, 0, r0, c7, c14, 1 @ clean & invalidate D / U line 376 addne r0, r0, r2 377 378 tst r1, r3 379 bic r1, r1, r3 380 mcrne p15, 0, r1, c7, c14, 1 @ clean & invalidate D / U line 381 cmp r0, r1 3821: 383 mcrlo p15, 0, r0, c7, c6, 1 @ invalidate D / U line 384 addlo r0, r0, r2 385 cmplo r0, r1 386 blo 1b 387 dsb st 388 ret lr 389ENDPROC(v7_dma_inv_range) 390 391/* 392 * v7_dma_clean_range(start,end) 393 * - start - virtual start address of region 394 * - end - virtual end address of region 395 */ 396v7_dma_clean_range: 397 dcache_line_size r2, r3 398 sub r3, r2, #1 399 bic r0, r0, r3 400#ifdef CONFIG_ARM_ERRATA_764369 401 ALT_SMP(W(dsb)) 402 ALT_UP(W(nop)) 403#endif 4041: 405 mcr p15, 0, r0, c7, c10, 1 @ clean D / U line 406 add r0, r0, r2 407 cmp r0, r1 408 blo 1b 409 dsb st 410 ret lr 411ENDPROC(v7_dma_clean_range) 412 413/* 414 * v7_dma_flush_range(start,end) 415 * - start - virtual start address of region 416 * - end - virtual end address of region 417 */ 418ENTRY(v7_dma_flush_range) 419 dcache_line_size r2, r3 420 sub r3, r2, #1 421 bic r0, r0, r3 422#ifdef CONFIG_ARM_ERRATA_764369 423 ALT_SMP(W(dsb)) 424 ALT_UP(W(nop)) 425#endif 4261: 427 mcr p15, 0, r0, c7, c14, 1 @ clean & invalidate D / U line 428 add r0, r0, r2 429 cmp r0, r1 430 blo 1b 431 dsb st 432 ret lr 433ENDPROC(v7_dma_flush_range) 434 435/* 436 * dma_map_area(start, size, dir) 437 * - start - kernel virtual start address 438 * - size - size of region 439 * - dir - DMA direction 440 */ 441ENTRY(v7_dma_map_area) 442 add r1, r1, r0 443 teq r2, #DMA_FROM_DEVICE 444 beq v7_dma_inv_range 445 b v7_dma_clean_range 446ENDPROC(v7_dma_map_area) 447 448/* 449 * dma_unmap_area(start, size, dir) 450 * - start - kernel virtual start address 451 * - size - size of region 452 * - dir - DMA direction 453 */ 454ENTRY(v7_dma_unmap_area) 455 add r1, r1, r0 456 teq r2, #DMA_TO_DEVICE 457 bne v7_dma_inv_range 458 ret lr 459ENDPROC(v7_dma_unmap_area) 460 461 __INITDATA 462 463 @ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S) 464 define_cache_functions v7 465 466 /* The Broadcom Brahma-B15 read-ahead cache requires some modifications 467 * to the v7_cache_fns, we only override the ones we need 468 */ 469#ifndef CONFIG_CACHE_B15_RAC 470 globl_equ b15_flush_kern_cache_all, v7_flush_kern_cache_all 471#endif 472 globl_equ b15_flush_icache_all, v7_flush_icache_all 473 globl_equ b15_flush_kern_cache_louis, v7_flush_kern_cache_louis 474 globl_equ b15_flush_user_cache_all, v7_flush_user_cache_all 475 globl_equ b15_flush_user_cache_range, v7_flush_user_cache_range 476 globl_equ b15_coherent_kern_range, v7_coherent_kern_range 477 globl_equ b15_coherent_user_range, v7_coherent_user_range 478 globl_equ b15_flush_kern_dcache_area, v7_flush_kern_dcache_area 479 480 globl_equ b15_dma_map_area, v7_dma_map_area 481 globl_equ b15_dma_unmap_area, v7_dma_unmap_area 482 globl_equ b15_dma_flush_range, v7_dma_flush_range 483 484 define_cache_functions b15 485