arch/arm/mm/cache-v6.S

   1 /*
   2  *  linux/arch/arm/mm/cache-v6.S
   3  *
   4  *  Copyright (C) 2001 Deep Blue Solutions Ltd.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  *
  10  *  This is the "shell" of the ARMv6 processor support.
  11  */
  12 #include <linux/linkage.h>
  13 #include <linux/init.h>
  14 #include <asm/assembler.h>
  15 #include <asm/unwind.h>
  16
  17 #include "proc-macros.S"
  18
  19 #define HARVARD_CACHE
  20 #define CACHE_LINE_SIZE         32
  21 #define D_CACHE_LINE_SIZE       32
  22 #define BTB_FLUSH_SIZE          8
  23
  24 /*
  25  *      v6_flush_icache_all()
  26  *
  27  *      Flush the whole I-cache.
  28  *
  29  *      ARM1136 erratum 411920 - Invalidate Instruction Cache operation can fail.
  30  *      This erratum is present in 1136, 1156 and 1176. It does not affect the
  31  *      MPCore.
  32  *
  33  *      Registers:
  34  *      r0 - set to 0
  35  *      r1 - corrupted
  36  */
  37 ENTRY(v6_flush_icache_all)
  38         mov     r0, #0
  39 #ifdef CONFIG_ARM_ERRATA_411920
  40         mrs     r1, cpsr
  41         cpsid   ifa                             @ disable interrupts
  42         mcr     p15, 0, r0, c7, c5, 0           @ invalidate entire I-cache
  43         mcr     p15, 0, r0, c7, c5, 0           @ invalidate entire I-cache
  44         mcr     p15, 0, r0, c7, c5, 0           @ invalidate entire I-cache
  45         mcr     p15, 0, r0, c7, c5, 0           @ invalidate entire I-cache
  46         msr     cpsr_cx, r1                     @ restore interrupts
  47         .rept   11                              @ ARM Ltd recommends at least
  48         nop                                     @ 11 NOPs
  49         .endr
  50 #else
  51         mcr     p15, 0, r0, c7, c5, 0           @ invalidate I-cache
  52 #endif
  53         mov     pc, lr
  54 ENDPROC(v6_flush_icache_all)
  55
  56 /*
  57  *      v6_flush_cache_all()
  58  *
  59  *      Flush the entire cache.
  60  *
  61  *      It is assumed that:
  62  */
  63 ENTRY(v6_flush_kern_cache_all)
  64         mov     r0, #0
  65 #ifdef HARVARD_CACHE
  66         mcr     p15, 0, r0, c7, c14, 0          @ D cache clean+invalidate
  67 #ifndef CONFIG_ARM_ERRATA_411920
  68         mcr     p15, 0, r0, c7, c5, 0           @ I+BTB cache invalidate
  69 #else
  70         b       v6_flush_icache_all
  71 #endif
  72 #else
  73         mcr     p15, 0, r0, c7, c15, 0          @ Cache clean+invalidate
  74 #endif
  75         mov     pc, lr
  76
  77 /*
  78  *      v6_flush_cache_all()
  79  *
  80  *      Flush all TLB entries in a particular address space
  81  *
  82  *      - mm    - mm_struct describing address space
  83  */
  84 ENTRY(v6_flush_user_cache_all)
  85         /*FALLTHROUGH*/
  86
  87 /*
  88  *      v6_flush_cache_range(start, end, flags)
  89  *
  90  *      Flush a range of TLB entries in the specified address space.
  91  *
  92  *      - start - start address (may not be aligned)
  93  *      - end   - end address (exclusive, may not be aligned)
  94  *      - flags - vm_area_struct flags describing address space
  95  *
  96  *      It is assumed that:
  97  *      - we have a VIPT cache.
  98  */
  99 ENTRY(v6_flush_user_cache_range)
 100         mov     pc, lr
 101
 102 /*
 103  *      v6_coherent_kern_range(start,end)
 104  *
 105  *      Ensure that the I and D caches are coherent within specified
 106  *      region.  This is typically used when code has been written to
 107  *      a memory region, and will be executed.
 108  *
 109  *      - start   - virtual start address of region
 110  *      - end     - virtual end address of region
 111  *
 112  *      It is assumed that:
 113  *      - the Icache does not read data from the write buffer
 114  */
 115 ENTRY(v6_coherent_kern_range)
 116         /* FALLTHROUGH */
 117
 118 /*
 119  *      v6_coherent_user_range(start,end)
 120  *
 121  *      Ensure that the I and D caches are coherent within specified
 122  *      region.  This is typically used when code has been written to
 123  *      a memory region, and will be executed.
 124  *
 125  *      - start   - virtual start address of region
 126  *      - end     - virtual end address of region
 127  *
 128  *      It is assumed that:
 129  *      - the Icache does not read data from the write buffer
 130  */
 131 ENTRY(v6_coherent_user_range)
 132  UNWIND(.fnstart                )
 133 #ifdef HARVARD_CACHE
 134         bic     r0, r0, #CACHE_LINE_SIZE - 1
 135 1:
 136  USER(  mcr     p15, 0, r0, c7, c10, 1  )       @ clean D line
 137         add     r0, r0, #CACHE_LINE_SIZE
 138 2:
 139         cmp     r0, r1
 140         blo     1b
 141 #endif
 142         mov     r0, #0
 143 #ifdef HARVARD_CACHE
 144         mcr     p15, 0, r0, c7, c10, 4          @ drain write buffer
 145 #ifndef CONFIG_ARM_ERRATA_411920
 146         mcr     p15, 0, r0, c7, c5, 0           @ I+BTB cache invalidate
 147 #else
 148         b       v6_flush_icache_all
 149 #endif
 150 #else
 151         mcr     p15, 0, r0, c7, c5, 6           @ invalidate BTB
 152 #endif
 153         mov     pc, lr
 154
 155 /*
 156  * Fault handling for the cache operation above. If the virtual address in r0
 157  * isn't mapped, just try the next page.
 158  */
 159 9001:
 160         mov     r0, r0, lsr #12
 161         mov     r0, r0, lsl #12
 162         add     r0, r0, #4096
 163         b       2b
 164  UNWIND(.fnend          )
 165 ENDPROC(v6_coherent_user_range)
 166 ENDPROC(v6_coherent_kern_range)
 167
 168 /*
 169  *      v6_flush_kern_dcache_area(void *addr, size_t size)
 170  *
 171  *      Ensure that the data held in the page kaddr is written back
 172  *      to the page in question.
 173  *
 174  *      - addr  - kernel address
 175  *      - size  - region size
 176  */
 177 ENTRY(v6_flush_kern_dcache_area)
 178         add     r1, r0, r1
 179 1:
 180 #ifdef HARVARD_CACHE
 181         mcr     p15, 0, r0, c7, c14, 1          @ clean & invalidate D line
 182 #else
 183         mcr     p15, 0, r0, c7, c15, 1          @ clean & invalidate unified line
 184 #endif
 185         add     r0, r0, #D_CACHE_LINE_SIZE
 186         cmp     r0, r1
 187         blo     1b
 188 #ifdef HARVARD_CACHE
 189         mov     r0, #0
 190         mcr     p15, 0, r0, c7, c10, 4
 191 #endif
 192         mov     pc, lr
 193
 194
 195 /*
 196  *      v6_dma_inv_range(start,end)
 197  *
 198  *      Invalidate the data cache within the specified region; we will
 199  *      be performing a DMA operation in this region and we want to
 200  *      purge old data in the cache.
 201  *
 202  *      - start   - virtual start address of region
 203  *      - end     - virtual end address of region
 204  */
 205 v6_dma_inv_range:
 206         tst     r0, #D_CACHE_LINE_SIZE - 1
 207         bic     r0, r0, #D_CACHE_LINE_SIZE - 1
 208 #ifdef HARVARD_CACHE
 209         mcrne   p15, 0, r0, c7, c10, 1          @ clean D line
 210 #else
 211         mcrne   p15, 0, r0, c7, c11, 1          @ clean unified line
 212 #endif
 213         tst     r1, #D_CACHE_LINE_SIZE - 1
 214         bic     r1, r1, #D_CACHE_LINE_SIZE - 1
 215 #ifdef HARVARD_CACHE
 216         mcrne   p15, 0, r1, c7, c14, 1          @ clean & invalidate D line
 217 #else
 218         mcrne   p15, 0, r1, c7, c15, 1          @ clean & invalidate unified line
 219 #endif
 220 1:
 221 #ifdef CONFIG_DMA_CACHE_RWFO
 222         ldr     r2, [r0]                        @ read for ownership
 223         str     r2, [r0]                        @ write for ownership
 224 #endif
 225 #ifdef HARVARD_CACHE
 226         mcr     p15, 0, r0, c7, c6, 1           @ invalidate D line
 227 #else
 228         mcr     p15, 0, r0, c7, c7, 1           @ invalidate unified line
 229 #endif
 230         add     r0, r0, #D_CACHE_LINE_SIZE
 231         cmp     r0, r1
 232         blo     1b
 233         mov     r0, #0
 234         mcr     p15, 0, r0, c7, c10, 4          @ drain write buffer
 235         mov     pc, lr
 236
 237 /*
 238  *      v6_dma_clean_range(start,end)
 239  *      - start   - virtual start address of region
 240  *      - end     - virtual end address of region
 241  */
 242 v6_dma_clean_range:
 243         bic     r0, r0, #D_CACHE_LINE_SIZE - 1
 244 1:
 245 #ifdef CONFIG_DMA_CACHE_RWFO
 246         ldr     r2, [r0]                        @ read for ownership
 247 #endif
 248 #ifdef HARVARD_CACHE
 249         mcr     p15, 0, r0, c7, c10, 1          @ clean D line
 250 #else
 251         mcr     p15, 0, r0, c7, c11, 1          @ clean unified line
 252 #endif
 253         add     r0, r0, #D_CACHE_LINE_SIZE
 254         cmp     r0, r1
 255         blo     1b
 256         mov     r0, #0
 257         mcr     p15, 0, r0, c7, c10, 4          @ drain write buffer
 258         mov     pc, lr
 259
 260 /*
 261  *      v6_dma_flush_range(start,end)
 262  *      - start   - virtual start address of region
 263  *      - end     - virtual end address of region
 264  */
 265 ENTRY(v6_dma_flush_range)
 266         bic     r0, r0, #D_CACHE_LINE_SIZE - 1
 267 1:
 268 #ifdef CONFIG_DMA_CACHE_RWFO
 269         ldr     r2, [r0]                        @ read for ownership
 270         str     r2, [r0]                        @ write for ownership
 271 #endif
 272 #ifdef HARVARD_CACHE
 273         mcr     p15, 0, r0, c7, c14, 1          @ clean & invalidate D line
 274 #else
 275         mcr     p15, 0, r0, c7, c15, 1          @ clean & invalidate line
 276 #endif
 277         add     r0, r0, #D_CACHE_LINE_SIZE
 278         cmp     r0, r1
 279         blo     1b
 280         mov     r0, #0
 281         mcr     p15, 0, r0, c7, c10, 4          @ drain write buffer
 282         mov     pc, lr
 283
 284 /*
 285  *      dma_map_area(start, size, dir)
 286  *      - start - kernel virtual start address
 287  *      - size  - size of region
 288  *      - dir   - DMA direction
 289  */
 290 ENTRY(v6_dma_map_area)
 291         add     r1, r1, r0
 292         teq     r2, #DMA_FROM_DEVICE
 293         beq     v6_dma_inv_range
 294 #ifndef CONFIG_DMA_CACHE_RWFO
 295         b       v6_dma_clean_range
 296 #else
 297         teq     r2, #DMA_TO_DEVICE
 298         beq     v6_dma_clean_range
 299         b       v6_dma_flush_range
 300 #endif
 301 ENDPROC(v6_dma_map_area)
 302
 303 /*
 304  *      dma_unmap_area(start, size, dir)
 305  *      - start - kernel virtual start address
 306  *      - size  - size of region
 307  *      - dir   - DMA direction
 308  */
 309 ENTRY(v6_dma_unmap_area)
 310 #ifndef CONFIG_DMA_CACHE_RWFO
 311         add     r1, r1, r0
 312         teq     r2, #DMA_TO_DEVICE
 313         bne     v6_dma_inv_range
 314 #endif
 315         mov     pc, lr
 316 ENDPROC(v6_dma_unmap_area)
 317
 318         __INITDATA
 319
 320         .type   v6_cache_fns, #object
 321 ENTRY(v6_cache_fns)
 322         .long   v6_flush_icache_all
 323         .long   v6_flush_kern_cache_all
 324         .long   v6_flush_user_cache_all
 325         .long   v6_flush_user_cache_range
 326         .long   v6_coherent_kern_range
 327         .long   v6_coherent_user_range
 328         .long   v6_flush_kern_dcache_area
 329         .long   v6_dma_map_area
 330         .long   v6_dma_unmap_area
 331         .long   v6_dma_flush_range
 332         .size   v6_cache_fns, . - v6_cache_fns