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  */
  34 ENTRY(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
  52 1:     sub     r2, r2, #1      @ NumSets--
  53        mov     r3, r4          @ Temp = NumWays
  54 2:     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
  63        isb
  64        mov     pc, lr
  65 ENDPROC(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  */
  75 ENTRY(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         mov     pc, lr
  80 ENDPROC(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
  90 ENTRY(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(moveq    pc, 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         moveq   pc, lr                          @ return if level == 0
 106         mov     r10, #0                         @ r10 (starting level) = 0
 107         b       flush_levels                    @ start flushing cache levels
 108 ENDPROC(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  */
 119 ENTRY(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
 126 flush_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
 148 loop1:
 149         mov     r9, r4                          @ create working copy of max way size
 150 loop2:
 151  ARM(   orr     r11, r10, r9, lsl r5    )       @ factor way and cache number into r11
 152  THUMB( lsl     r6, r9, r5              )
 153  THUMB( orr     r11, r10, r6            )       @ factor way and cache number into r11
 154  ARM(   orr     r11, r11, r7, lsl r2    )       @ factor index number into r11
 155  THUMB( lsl     r6, r7, 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 way
 159         bge     loop2
 160         subs    r7, r7, #1                      @ decrement the index
 161         bge     loop1
 162 skip:
 163         add     r10, r10, #2                    @ increment cache number
 164         cmp     r3, r10
 165         bgt     flush_levels
 166 finished:
 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
 170         isb
 171         mov     pc, lr
 172 ENDPROC(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  */
 185 ENTRY(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         mov     pc, lr
 195 ENDPROC(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  */
 203 ENTRY(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         mov     pc, lr
 213 ENDPROC(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  */
 222 ENTRY(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  */
 237 ENTRY(v7_flush_user_cache_range)
 238         mov     pc, lr
 239 ENDPROC(v7_flush_user_cache_all)
 240 ENDPROC(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  */
 255 ENTRY(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  */
 271 ENTRY(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
 280 1:
 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
 286         icache_line_size r2, r3
 287         sub     r3, r2, #1
 288         bic     r12, r0, r3
 289 2:
 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
 298         isb
 299         mov     pc, 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  */
 305 9001:
 306 #ifdef CONFIG_ARM_ERRATA_775420
 307         dsb
 308 #endif
 309         mov     r0, #-EFAULT
 310         mov     pc, lr
 311  UNWIND(.fnend          )
 312 ENDPROC(v7_coherent_kern_range)
 313 ENDPROC(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  */
 324 ENTRY(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
 333 1:
 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
 339         mov     pc, lr
 340 ENDPROC(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  */
 352 v7_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
 366 1:
 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
 372         mov     pc, lr
 373 ENDPROC(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  */
 380 v7_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
 388 1:
 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
 394         mov     pc, lr
 395 ENDPROC(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  */
 402 ENTRY(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
 410 1:
 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
 416         mov     pc, lr
 417 ENDPROC(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  */
 425 ENTRY(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
 430 ENDPROC(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  */
 438 ENTRY(v7_dma_unmap_area)
 439         add     r1, r1, r0
 440         teq     r2, #DMA_TO_DEVICE
 441         bne     v7_dma_inv_range
 442         mov     pc, lr
 443 ENDPROC(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