LXR linux/arch/arm/mm/cache-v7.S

   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
  19#include "proc-macros.S"
  20
  21/*
  22 * The secondary kernel init calls v7_flush_dcache_all before it enables
  23 * the L1; however, the L1 comes out of reset in an undefined state, so
  24 * the clean + invalidate performed by v7_flush_dcache_all causes a bunch
  25 * of cache lines with uninitialized data and uninitialized tags to get
  26 * written out to memory, which does really unpleasant things to the main
  27 * processor.  We fix this by performing an invalidate, rather than a
  28 * clean + invalidate, before jumping into the kernel.
  29 *
  30 * This function is cloned from arch/arm/mach-tegra/headsmp.S, and needs
  31 * to be called for both secondary cores startup and primary core resume
  32 * procedures.
  33 */
  34ENTRY(v7_invalidate_l1)
  35       mov     r0, #0
  36       mcr     p15, 2, r0, c0, c0, 0
  37       mrc     p15, 1, r0, c0, c0, 0
  38
  39       ldr     r1, =0x7fff
  40       and     r2, r1, r0, lsr #13
  41
  42       ldr     r1, =0x3ff
  43
  44       and     r3, r1, r0, lsr #3      @ NumWays - 1
  45       add     r2, r2, #1              @ NumSets
  46
  47       and     r0, r0, #0x7
  48       add     r0, r0, #4      @ SetShift
  49
  50       clz     r1, r3          @ WayShift
  51       add     r4, r3, #1      @ NumWays
  521:     sub     r2, r2, #1      @ NumSets--
  53       mov     r3, r4          @ Temp = NumWays
  542:     subs    r3, r3, #1      @ Temp--
  55       mov     r5, r3, lsl r1
  56       mov     r6, r2, lsl r0
  57       orr     r5, r5, r6      @ Reg = (Temp<<WayShift)|(NumSets<<SetShift)
  58       mcr     p15, 0, r5, c7, c6, 2
  59       bgt     2b
  60       cmp     r2, #0
  61       bgt     1b
  62       dsb     st
  63       isb
  64       ret     lr
  65ENDPROC(v7_invalidate_l1)
  66
  67/*
  68 *      v7_flush_icache_all()
  69 *
  70 *      Flush the whole I-cache.
  71 *
  72 *      Registers:
  73 *      r0 - set to 0
  74 */
  75ENTRY(v7_flush_icache_all)
  76        mov     r0, #0
  77        ALT_SMP(mcr     p15, 0, r0, c7, c1, 0)          @ invalidate I-cache inner shareable
  78        ALT_UP(mcr      p15, 0, r0, c7, c5, 0)          @ I+BTB cache invalidate
  79        ret     lr
  80ENDPROC(v7_flush_icache_all)
  81
  82 /*
  83 *     v7_flush_dcache_louis()
  84 *
  85 *     Flush the D-cache up to the Level of Unification Inner Shareable
  86 *
  87 *     Corrupted registers: r0-r7, r9-r11 (r6 only in Thumb mode)
  88 */
  89
  90ENTRY(v7_flush_dcache_louis)
  91        dmb                                     @ ensure ordering with previous memory accesses
  92        mrc     p15, 1, r0, c0, c0, 1           @ read clidr, r0 = clidr
  93        ALT_SMP(ands    r3, r0, #(7 << 21))     @ extract LoUIS from clidr
  94        ALT_UP(ands     r3, r0, #(7 << 27))     @ extract LoUU from clidr
  95#ifdef CONFIG_ARM_ERRATA_643719
  96        ALT_SMP(mrceq   p15, 0, r2, c0, c0, 0)  @ read main ID register
  97        ALT_UP(reteq    lr)                     @ LoUU is zero, so nothing to do
  98        ldreq   r1, =0x410fc090                 @ ID of ARM Cortex A9 r0p?
  99        biceq   r2, r2, #0x0000000f             @ clear minor revision number
 100        teqeq   r2, r1                          @ test for errata affected core and if so...
 101        orreqs  r3, #(1 << 21)                  @   fix LoUIS value (and set flags state to 'ne')
 102#endif
 103        ALT_SMP(mov     r3, r3, lsr #20)        @ r3 = LoUIS * 2
 104        ALT_UP(mov      r3, r3, lsr #26)        @ r3 = LoUU * 2
 105        reteq   lr                              @ return if level == 0
 106        mov     r10, #0                         @ r10 (starting level) = 0
 107        b       flush_levels                    @ start flushing cache levels
 108ENDPROC(v7_flush_dcache_louis)
 109
 110/*
 111 *      v7_flush_dcache_all()
 112 *
 113 *      Flush the whole D-cache.
 114 *
 115 *      Corrupted registers: r0-r7, r9-r11 (r6 only in Thumb mode)
 116 *
 117 *      - mm    - mm_struct describing address space
 118 */
 119ENTRY(v7_flush_dcache_all)
 120        dmb                                     @ ensure ordering with previous memory accesses
 121        mrc     p15, 1, r0, c0, c0, 1           @ read clidr
 122        ands    r3, r0, #0x7000000              @ extract loc from clidr
 123        mov     r3, r3, lsr #23                 @ left align loc bit field
 124        beq     finished                        @ if loc is 0, then no need to clean
 125        mov     r10, #0                         @ start clean at cache level 0
 126flush_levels:
 127        add     r2, r10, r10, lsr #1            @ work out 3x current cache level
 128        mov     r1, r0, lsr r2                  @ extract cache type bits from clidr
 129        and     r1, r1, #7                      @ mask of the bits for current cache only
 130        cmp     r1, #2                          @ see what cache we have at this level
 131        blt     skip                            @ skip if no cache, or just i-cache
 132#ifdef CONFIG_PREEMPT
 133        save_and_disable_irqs_notrace r9        @ make cssr&csidr read atomic
 134#endif
 135        mcr     p15, 2, r10, c0, c0, 0          @ select current cache level in cssr
 136        isb                                     @ isb to sych the new cssr&csidr
 137        mrc     p15, 1, r1, c0, c0, 0           @ read the new csidr
 138#ifdef CONFIG_PREEMPT
 139        restore_irqs_notrace r9
 140#endif
 141        and     r2, r1, #7                      @ extract the length of the cache lines
 142        add     r2, r2, #4                      @ add 4 (line length offset)
 143        ldr     r4, =0x3ff
 144        ands    r4, r4, r1, lsr #3              @ find maximum number on the way size
 145        clz     r5, r4                          @ find bit position of way size increment
 146        ldr     r7, =0x7fff
 147        ands    r7, r7, r1, lsr #13             @ extract max number of the index size
 148loop1:
 149        mov     r9, r7                          @ create working copy of max index
 150loop2:
 151 ARM(   orr     r11, r10, r4, lsl r5    )       @ factor way and cache number into r11
 152 THUMB( lsl     r6, r4, r5              )
 153 THUMB( orr     r11, r10, r6            )       @ factor way and cache number into r11
 154 ARM(   orr     r11, r11, r9, lsl r2    )       @ factor index number into r11
 155 THUMB( lsl     r6, r9, r2              )
 156 THUMB( orr     r11, r11, r6            )       @ factor index number into r11
 157        mcr     p15, 0, r11, c7, c14, 2         @ clean & invalidate by set/way
 158        subs    r9, r9, #1                      @ decrement the index
 159        bge     loop2
 160        subs    r4, r4, #1                      @ decrement the way
 161        bge     loop1
 162skip:
 163        add     r10, r10, #2                    @ increment cache number
 164        cmp     r3, r10
 165        bgt     flush_levels
 166finished:
 167        mov     r10, #0                         @ swith back to cache level 0
 168        mcr     p15, 2, r10, c0, c0, 0          @ select current cache level in cssr
 169        dsb     st
 170        isb
 171        ret     lr
 172ENDPROC(v7_flush_dcache_all)
 173
 174/*
 175 *      v7_flush_cache_all()
 176 *
 177 *      Flush the entire cache system.
 178 *  The data cache flush is now achieved using atomic clean / invalidates
 179 *  working outwards from L1 cache. This is done using Set/Way based cache
 180 *  maintenance instructions.
 181 *  The instruction cache can still be invalidated back to the point of
 182 *  unification in a single instruction.
 183 *
 184 */
 185ENTRY(v7_flush_kern_cache_all)
 186 ARM(   stmfd   sp!, {r4-r5, r7, r9-r11, lr}    )
 187 THUMB( stmfd   sp!, {r4-r7, r9-r11, lr}        )
 188        bl      v7_flush_dcache_all
 189        mov     r0, #0
 190        ALT_SMP(mcr     p15, 0, r0, c7, c1, 0)  @ invalidate I-cache inner shareable
 191        ALT_UP(mcr      p15, 0, r0, c7, c5, 0)  @ I+BTB cache invalidate
 192 ARM(   ldmfd   sp!, {r4-r5, r7, r9-r11, lr}    )
 193 THUMB( ldmfd   sp!, {r4-r7, r9-r11, lr}        )
 194        ret     lr
 195ENDPROC(v7_flush_kern_cache_all)
 196
 197 /*
 198 *     v7_flush_kern_cache_louis(void)
 199 *
 200 *     Flush the data cache up to Level of Unification Inner Shareable.
 201 *     Invalidate the I-cache to the point of unification.
 202 */
 203ENTRY(v7_flush_kern_cache_louis)
 204 ARM(   stmfd   sp!, {r4-r5, r7, r9-r11, lr}    )
 205 THUMB( stmfd   sp!, {r4-r7, r9-r11, lr}        )
 206        bl      v7_flush_dcache_louis
 207        mov     r0, #0
 208        ALT_SMP(mcr     p15, 0, r0, c7, c1, 0)  @ invalidate I-cache inner shareable
 209        ALT_UP(mcr      p15, 0, r0, c7, c5, 0)  @ I+BTB cache invalidate
 210 ARM(   ldmfd   sp!, {r4-r5, r7, r9-r11, lr}    )
 211 THUMB( ldmfd   sp!, {r4-r7, r9-r11, lr}        )
 212        ret     lr
 213ENDPROC(v7_flush_kern_cache_louis)
 214
 215/*
 216 *      v7_flush_cache_all()
 217 *
 218 *      Flush all TLB entries in a particular address space
 219 *
 220 *      - mm    - mm_struct describing address space
 221 */
 222ENTRY(v7_flush_user_cache_all)
 223        /*FALLTHROUGH*/
 224
 225/*
 226 *      v7_flush_cache_range(start, end, flags)
 227 *
 228 *      Flush a range of TLB entries in the specified address space.
 229 *
 230 *      - start - start address (may not be aligned)
 231 *      - end   - end address (exclusive, may not be aligned)
 232 *      - flags - vm_area_struct flags describing address space
 233 *
 234 *      It is assumed that:
 235 *      - we have a VIPT cache.
 236 */
 237ENTRY(v7_flush_user_cache_range)
 238        ret     lr
 239ENDPROC(v7_flush_user_cache_all)
 240ENDPROC(v7_flush_user_cache_range)
 241
 242/*
 243 *      v7_coherent_kern_range(start,end)
 244 *
 245 *      Ensure that the I and D caches are coherent within specified
 246 *      region.  This is typically used when code has been written to
 247 *      a memory region, and will be executed.
 248 *
 249 *      - start   - virtual start address of region
 250 *      - end     - virtual end address of region
 251 *
 252 *      It is assumed that:
 253 *      - the Icache does not read data from the write buffer
 254 */
 255ENTRY(v7_coherent_kern_range)
 256        /* FALLTHROUGH */
 257
 258/*
 259 *      v7_coherent_user_range(start,end)
 260 *
 261 *      Ensure that the I and D caches are coherent within specified
 262 *      region.  This is typically used when code has been written to
 263 *      a memory region, and will be executed.
 264 *
 265 *      - start   - virtual start address of region
 266 *      - end     - virtual end address of region
 267 *
 268 *      It is assumed that:
 269 *      - the Icache does not read data from the write buffer
 270 */
 271ENTRY(v7_coherent_user_range)
 272 UNWIND(.fnstart                )
 273        dcache_line_size r2, r3
 274        sub     r3, r2, #1
 275        bic     r12, r0, r3
 276#ifdef CONFIG_ARM_ERRATA_764369
 277        ALT_SMP(W(dsb))
 278        ALT_UP(W(nop))
 279#endif
 2801:
 281 USER(  mcr     p15, 0, r12, c7, c11, 1 )       @ clean D line to the point of unification
 282        add     r12, r12, r2
 283        cmp     r12, r1
 284        blo     1b
 285        dsb     ishst
 286        icache_line_size r2, r3
 287        sub     r3, r2, #1
 288        bic     r12, r0, r3
 2892:
 290 USER(  mcr     p15, 0, r12, c7, c5, 1  )       @ invalidate I line
 291        add     r12, r12, r2
 292        cmp     r12, r1
 293        blo     2b
 294        mov     r0, #0
 295        ALT_SMP(mcr     p15, 0, r0, c7, c1, 6)  @ invalidate BTB Inner Shareable
 296        ALT_UP(mcr      p15, 0, r0, c7, c5, 6)  @ invalidate BTB
 297        dsb     ishst
 298        isb
 299        ret     lr
 300
 301/*
 302 * Fault handling for the cache operation above. If the virtual address in r0
 303 * isn't mapped, fail with -EFAULT.
 304 */
 3059001:
 306#ifdef CONFIG_ARM_ERRATA_775420
 307        dsb
 308#endif
 309        mov     r0, #-EFAULT
 310        ret     lr
 311 UNWIND(.fnend          )
 312ENDPROC(v7_coherent_kern_range)
 313ENDPROC(v7_coherent_user_range)
 314
 315/*
 316 *      v7_flush_kern_dcache_area(void *addr, size_t size)
 317 *
 318 *      Ensure that the data held in the page kaddr is written back
 319 *      to the page in question.
 320 *
 321 *      - addr  - kernel address
 322 *      - size  - region size
 323 */
 324ENTRY(v7_flush_kern_dcache_area)
 325        dcache_line_size r2, r3
 326        add     r1, r0, r1
 327        sub     r3, r2, #1
 328        bic     r0, r0, r3
 329#ifdef CONFIG_ARM_ERRATA_764369
 330        ALT_SMP(W(dsb))
 331        ALT_UP(W(nop))
 332#endif
 3331:
 334        mcr     p15, 0, r0, c7, c14, 1          @ clean & invalidate D line / unified line
 335        add     r0, r0, r2
 336        cmp     r0, r1
 337        blo     1b
 338        dsb     st
 339        ret     lr
 340ENDPROC(v7_flush_kern_dcache_area)
 341
 342/*
 343 *      v7_dma_inv_range(start,end)
 344 *
 345 *      Invalidate the data cache within the specified region; we will
 346 *      be performing a DMA operation in this region and we want to
 347 *      purge old data in the cache.
 348 *
 349 *      - start   - virtual start address of region
 350 *      - end     - virtual end address of region
 351 */
 352v7_dma_inv_range:
 353        dcache_line_size r2, r3
 354        sub     r3, r2, #1
 355        tst     r0, r3
 356        bic     r0, r0, r3
 357#ifdef CONFIG_ARM_ERRATA_764369
 358        ALT_SMP(W(dsb))
 359        ALT_UP(W(nop))
 360#endif
 361        mcrne   p15, 0, r0, c7, c14, 1          @ clean & invalidate D / U line
 362
 363        tst     r1, r3
 364        bic     r1, r1, r3
 365        mcrne   p15, 0, r1, c7, c14, 1          @ clean & invalidate D / U line
 3661:
 367        mcr     p15, 0, r0, c7, c6, 1           @ invalidate D / U line
 368        add     r0, r0, r2
 369        cmp     r0, r1
 370        blo     1b
 371        dsb     st
 372        ret     lr
 373ENDPROC(v7_dma_inv_range)
 374
 375/*
 376 *      v7_dma_clean_range(start,end)
 377 *      - start   - virtual start address of region
 378 *      - end     - virtual end address of region
 379 */
 380v7_dma_clean_range:
 381        dcache_line_size r2, r3
 382        sub     r3, r2, #1
 383        bic     r0, r0, r3
 384#ifdef CONFIG_ARM_ERRATA_764369
 385        ALT_SMP(W(dsb))
 386        ALT_UP(W(nop))
 387#endif
 3881:
 389        mcr     p15, 0, r0, c7, c10, 1          @ clean D / U line
 390        add     r0, r0, r2
 391        cmp     r0, r1
 392        blo     1b
 393        dsb     st
 394        ret     lr
 395ENDPROC(v7_dma_clean_range)
 396
 397/*
 398 *      v7_dma_flush_range(start,end)
 399 *      - start   - virtual start address of region
 400 *      - end     - virtual end address of region
 401 */
 402ENTRY(v7_dma_flush_range)
 403        dcache_line_size r2, r3
 404        sub     r3, r2, #1
 405        bic     r0, r0, r3
 406#ifdef CONFIG_ARM_ERRATA_764369
 407        ALT_SMP(W(dsb))
 408        ALT_UP(W(nop))
 409#endif
 4101:
 411        mcr     p15, 0, r0, c7, c14, 1          @ clean & invalidate D / U line
 412        add     r0, r0, r2
 413        cmp     r0, r1
 414        blo     1b
 415        dsb     st
 416        ret     lr
 417ENDPROC(v7_dma_flush_range)
 418
 419/*
 420 *      dma_map_area(start, size, dir)
 421 *      - start - kernel virtual start address
 422 *      - size  - size of region
 423 *      - dir   - DMA direction
 424 */
 425ENTRY(v7_dma_map_area)
 426        add     r1, r1, r0
 427        teq     r2, #DMA_FROM_DEVICE
 428        beq     v7_dma_inv_range
 429        b       v7_dma_clean_range
 430ENDPROC(v7_dma_map_area)
 431
 432/*
 433 *      dma_unmap_area(start, size, dir)
 434 *      - start - kernel virtual start address
 435 *      - size  - size of region
 436 *      - dir   - DMA direction
 437 */
 438ENTRY(v7_dma_unmap_area)
 439        add     r1, r1, r0
 440        teq     r2, #DMA_TO_DEVICE
 441        bne     v7_dma_inv_range
 442        ret     lr
 443ENDPROC(v7_dma_unmap_area)
 444
 445        __INITDATA
 446
 447        @ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
 448        define_cache_functions v7
 449