2  *  linux/arch/arm/mm/cache-v7.S
 
   4  *  Copyright (C) 2001 Deep Blue Solutions Ltd.
 
   5  *  Copyright (C) 2005 ARM Ltd.
 
   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.
 
  11  *  This is the "shell" of the ARMv7 processor support.
 
  13 #include <linux/linkage.h>
 
  14 #include <linux/init.h>
 
  15 #include "assembler.h"
 
  16 #include <asm/unwind.h>
 
  18 #include "proc-macros.S"
 
  21  *      v7_flush_icache_all()
 
  23  *      Flush the whole I-cache.
 
  28 ENTRY(v7_flush_icache_all)
 
  30         ALT_SMP(mcr     p15, 0, r0, c7, c1, 0)          @ invalidate I-cache inner shareable
 
  31         ALT_UP(mcr      p15, 0, r0, c7, c5, 0)          @ I+BTB cache invalidate
 
  33 ENDPROC(v7_flush_icache_all)
 
  36  *      v7_flush_dcache_all()
 
  38  *      Flush the whole D-cache.
 
  40  *      Corrupted registers: r0-r7, r9-r11 (r6 only in Thumb mode)
 
  42  *      - mm    - mm_struct describing address space
 
  44 ENTRY(v7_flush_dcache_all)
 
  45         dmb                                     @ ensure ordering with previous memory accesses
 
  46         mrc     p15, 1, r0, c0, c0, 1           @ read clidr
 
  47         ands    r3, r0, #0x7000000              @ extract loc from clidr
 
  48         mov     r3, r3, lsr #23                 @ left align loc bit field
 
  49         beq     finished                        @ if loc is 0, then no need to clean
 
  50         mov     r10, #0                         @ start clean at cache level 0
 
  52         add     r2, r10, r10, lsr #1            @ work out 3x current cache level
 
  53         mov     r1, r0, lsr r2                  @ extract cache type bits from clidr
 
  54         and     r1, r1, #7                      @ mask of the bits for current cache only
 
  55         cmp     r1, #2                          @ see what cache we have at this level
 
  56         blt     skip                            @ skip if no cache, or just i-cache
 
  57         mcr     p15, 2, r10, c0, c0, 0          @ select current cache level in cssr
 
  58         isb                                     @ isb to sych the new cssr&csidr
 
  59         mrc     p15, 1, r1, c0, c0, 0           @ read the new csidr
 
  60         and     r2, r1, #7                      @ extract the length of the cache lines
 
  61         add     r2, r2, #4                      @ add 4 (line length offset)
 
  63         ands    r4, r4, r1, lsr #3              @ find maximum number on the way size
 
  64         clz     r5, r4                          @ find bit position of way size increment
 
  66         ands    r7, r7, r1, lsr #13             @ extract max number of the index size
 
  68         mov     r9, r4                          @ create working copy of max way size
 
  70  ARM(   orr     r11, r10, r9, lsl r5    )       @ factor way and cache number into r11
 
  71  THUMB( lsl     r6, r9, r5              )
 
  72  THUMB( orr     r11, r10, r6            )       @ factor way and cache number into r11
 
  73  ARM(   orr     r11, r11, r7, lsl r2    )       @ factor index number into r11
 
  74  THUMB( lsl     r6, r7, r2              )
 
  75  THUMB( orr     r11, r11, r6            )       @ factor index number into r11
 
  76         mcr     p15, 0, r11, c7, c14, 2         @ clean & invalidate by set/way
 
  77         subs    r9, r9, #1                      @ decrement the way
 
  79         subs    r7, r7, #1                      @ decrement the index
 
  82         add     r10, r10, #2                    @ increment cache number
 
  86         mov     r10, #0                         @ swith back to cache level 0
 
  87         mcr     p15, 2, r10, c0, c0, 0          @ select current cache level in cssr
 
  91 ENDPROC(v7_flush_dcache_all)
 
  94  *      v7_flush_cache_all()
 
  96  *      Flush the entire cache system.
 
  97  *  The data cache flush is now achieved using atomic clean / invalidates
 
  98  *  working outwards from L1 cache. This is done using Set/Way based cache
 
  99  *  maintenance instructions.
 
 100  *  The instruction cache can still be invalidated back to the point of
 
 101  *  unification in a single instruction.
 
 104 ENTRY(v7_flush_kern_cache_all)
 
 105  ARM(   stmfd   sp!, {r4-r5, r7, r9-r11, lr}    )
 
 106  THUMB( stmfd   sp!, {r4-r7, r9-r11, lr}        )
 
 107         bl      v7_flush_dcache_all
 
 109         ALT_SMP(mcr     p15, 0, r0, c7, c1, 0)  @ invalidate I-cache inner shareable
 
 110         ALT_UP(mcr      p15, 0, r0, c7, c5, 0)  @ I+BTB cache invalidate
 
 111  ARM(   ldmfd   sp!, {r4-r5, r7, r9-r11, lr}    )
 
 112  THUMB( ldmfd   sp!, {r4-r7, r9-r11, lr}        )
 
 114 ENDPROC(v7_flush_kern_cache_all)
 
 117  *      v7_flush_cache_all()
 
 119  *      Flush all TLB entries in a particular address space
 
 121  *      - mm    - mm_struct describing address space
 
 123 ENTRY(v7_flush_user_cache_all)
 
 127  *      v7_flush_cache_range(start, end, flags)
 
 129  *      Flush a range of TLB entries in the specified address space.
 
 131  *      - start - start address (may not be aligned)
 
 132  *      - end   - end address (exclusive, may not be aligned)
 
 133  *      - flags - vm_area_struct flags describing address space
 
 135  *      It is assumed that:
 
 136  *      - we have a VIPT cache.
 
 138 ENTRY(v7_flush_user_cache_range)
 
 140 ENDPROC(v7_flush_user_cache_all)
 
 141 ENDPROC(v7_flush_user_cache_range)
 
 144  *      v7_coherent_kern_range(start,end)
 
 146  *      Ensure that the I and D caches are coherent within specified
 
 147  *      region.  This is typically used when code has been written to
 
 148  *      a memory region, and will be executed.
 
 150  *      - start   - virtual start address of region
 
 151  *      - end     - virtual end address of region
 
 153  *      It is assumed that:
 
 154  *      - the Icache does not read data from the write buffer
 
 156 ENTRY(v7_coherent_kern_range)
 
 160  *      v7_coherent_user_range(start,end)
 
 162  *      Ensure that the I and D caches are coherent within specified
 
 163  *      region.  This is typically used when code has been written to
 
 164  *      a memory region, and will be executed.
 
 166  *      - start   - virtual start address of region
 
 167  *      - end     - virtual end address of region
 
 169  *      It is assumed that:
 
 170  *      - the Icache does not read data from the write buffer
 
 172 ENTRY(v7_coherent_user_range)
 
 174         dcache_line_size r2, r3
 
 178  USER(  mcr     p15, 0, r12, c7, c11, 1 )       @ clean D line to the point of unification
 
 183         icache_line_size r2, r3
 
 187  USER(  mcr     p15, 0, r12, c7, c5, 1  )       @ invalidate I line
 
 193         ALT_SMP(mcr     p15, 0, r0, c7, c1, 6)  @ invalidate BTB Inner Shareable
 
 194         ALT_UP(mcr      p15, 0, r0, c7, c5, 6)  @ invalidate BTB
 
 200  * Fault handling for the cache operation above. If the virtual address in r0
 
 201  * isn't mapped, just try the next page.
 
 204         mov     r12, r12, lsr #12
 
 205         mov     r12, r12, lsl #12
 
 209 ENDPROC(v7_coherent_kern_range)
 
 210 ENDPROC(v7_coherent_user_range)
 
 213  *      v7_flush_kern_dcache_area(void *addr, size_t size)
 
 215  *      Ensure that the data held in the page kaddr is written back
 
 216  *      to the page in question.
 
 218  *      - addr  - kernel address
 
 219  *      - size  - region size
 
 221 ENTRY(v7_flush_kern_dcache_area)
 
 222         dcache_line_size r2, r3
 
 225         mcr     p15, 0, r0, c7, c14, 1          @ clean & invalidate D line / unified line
 
 231 ENDPROC(v7_flush_kern_dcache_area)
 
 234  *      v7_dma_inv_range(start,end)
 
 236  *      Invalidate the data cache within the specified region; we will
 
 237  *      be performing a DMA operation in this region and we want to
 
 238  *      purge old data in the cache.
 
 240  *      - start   - virtual start address of region
 
 241  *      - end     - virtual end address of region
 
 244         dcache_line_size r2, r3
 
 248         mcrne   p15, 0, r0, c7, c14, 1          @ clean & invalidate D / U line
 
 252         mcrne   p15, 0, r1, c7, c14, 1          @ clean & invalidate D / U line
 
 254         mcr     p15, 0, r0, c7, c6, 1           @ invalidate D / U line
 
 260 ENDPROC(v7_dma_inv_range)
 
 263  *      v7_dma_clean_range(start,end)
 
 264  *      - start   - virtual start address of region
 
 265  *      - end     - virtual end address of region
 
 268         dcache_line_size r2, r3
 
 272         mcr     p15, 0, r0, c7, c10, 1          @ clean D / U line
 
 278 ENDPROC(v7_dma_clean_range)
 
 281  *      v7_dma_flush_range(start,end)
 
 282  *      - start   - virtual start address of region
 
 283  *      - end     - virtual end address of region
 
 285 ENTRY(v7_dma_flush_range)
 
 286         dcache_line_size r2, r3
 
 290         mcr     p15, 0, r0, c7, c14, 1          @ clean & invalidate D / U line
 
 296 ENDPROC(v7_dma_flush_range)
 
 300         .type   v7_cache_fns, #object
 
 302         .long   v7_flush_icache_all
 
 303         .long   v7_flush_kern_cache_all
 
 304         .long   v7_flush_user_cache_all
 
 305         .long   v7_flush_user_cache_range
 
 306         .long   v7_coherent_kern_range
 
 307         .long   v7_coherent_user_range
 
 308         .long   v7_flush_kern_dcache_area
 
 309         .long   v7_dma_flush_range
 
 310         .size   v7_cache_fns, . - v7_cache_fns