arch/mn10300/mm/cache-flush-mn10300.S

   1 /* MN10300 CPU core caching routines
   2  *
   3  * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
   4  * Written by David Howells (dhowells@redhat.com)
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public Licence
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the Licence, or (at your option) any later version.
  10  */
  11
  12 #include <linux/sys.h>
  13 #include <linux/linkage.h>
  14 #include <asm/smp.h>
  15 #include <asm/page.h>
  16 #include <asm/cache.h>
  17
  18         .am33_2
  19         .globl mn10300_dcache_flush
  20         .globl mn10300_dcache_flush_page
  21         .globl mn10300_dcache_flush_range
  22         .globl mn10300_dcache_flush_range2
  23         .globl mn10300_dcache_flush_inv
  24         .globl mn10300_dcache_flush_inv_page
  25         .globl mn10300_dcache_flush_inv_range
  26         .globl mn10300_dcache_flush_inv_range2
  27
  28 ###############################################################################
  29 #
  30 # void mn10300_dcache_flush(void)
  31 # Flush the entire data cache back to RAM
  32 #
  33 ###############################################################################
  34         ALIGN
  35 mn10300_dcache_flush:
  36         movhu   (CHCTR),d0
  37         btst    CHCTR_DCEN,d0
  38         beq     mn10300_dcache_flush_end
  39
  40         # read the addresses tagged in the cache's tag RAM and attempt to flush
  41         # those addresses specifically
  42         # - we rely on the hardware to filter out invalid tag entry addresses
  43         mov     DCACHE_TAG(0,0),a0              # dcache tag RAM access address
  44         mov     DCACHE_PURGE(0,0),a1            # dcache purge request address
  45         mov     L1_CACHE_NWAYS*L1_CACHE_NENTRIES,d1  # total number of entries
  46
  47 mn10300_dcache_flush_loop:
  48         mov     (a0),d0
  49         and     L1_CACHE_TAG_ADDRESS|L1_CACHE_TAG_ENTRY,d0
  50         or      L1_CACHE_TAG_VALID,d0           # retain valid entries in the
  51                                                 # cache
  52         mov     d0,(a1)                         # conditional purge
  53
  54 mn10300_dcache_flush_skip:
  55         add     L1_CACHE_BYTES,a0
  56         add     L1_CACHE_BYTES,a1
  57         add     -1,d1
  58         bne     mn10300_dcache_flush_loop
  59
  60 mn10300_dcache_flush_end:
  61         ret     [],0
  62
  63 ###############################################################################
  64 #
  65 # void mn10300_dcache_flush_page(unsigned start)
  66 # void mn10300_dcache_flush_range(unsigned start, unsigned end)
  67 # void mn10300_dcache_flush_range2(unsigned start, unsigned size)
  68 # Flush a range of addresses on a page in the dcache
  69 #
  70 ###############################################################################
  71         ALIGN
  72 mn10300_dcache_flush_page:
  73         mov     PAGE_SIZE,d1
  74 mn10300_dcache_flush_range2:
  75         add     d0,d1
  76 mn10300_dcache_flush_range:
  77         movm    [d2,d3],(sp)
  78
  79         movhu   (CHCTR),d2
  80         btst    CHCTR_DCEN,d2
  81         beq     mn10300_dcache_flush_range_end
  82
  83         # round start addr down
  84         and     L1_CACHE_TAG_ADDRESS|L1_CACHE_TAG_ENTRY,d0
  85         mov     d0,a1
  86
  87         add     L1_CACHE_BYTES,d1                       # round end addr up
  88         and     L1_CACHE_TAG_ADDRESS|L1_CACHE_TAG_ENTRY,d1
  89
  90         # write a request to flush all instances of an address from the cache
  91         mov     DCACHE_PURGE(0,0),a0
  92         mov     a1,d0
  93         and     L1_CACHE_TAG_ENTRY,d0
  94         add     d0,a0                           # starting dcache purge control
  95                                                 # reg address
  96
  97         sub     a1,d1
  98         lsr     L1_CACHE_SHIFT,d1               # total number of entries to
  99                                                 # examine
 100
 101         or      L1_CACHE_TAG_VALID,a1           # retain valid entries in the
 102                                                 # cache
 103
 104 mn10300_dcache_flush_range_loop:
 105         mov     a1,(L1_CACHE_WAYDISP*0,a0)      # conditionally purge this line
 106                                                 # all ways
 107
 108         add     L1_CACHE_BYTES,a0
 109         add     L1_CACHE_BYTES,a1
 110         and     ~L1_CACHE_WAYDISP,a0            # make sure way stay on way 0
 111         add     -1,d1
 112         bne     mn10300_dcache_flush_range_loop
 113
 114 mn10300_dcache_flush_range_end:
 115         ret     [d2,d3],8
 116
 117 ###############################################################################
 118 #
 119 # void mn10300_dcache_flush_inv(void)
 120 # Flush the entire data cache and invalidate all entries
 121 #
 122 ###############################################################################
 123         ALIGN
 124 mn10300_dcache_flush_inv:
 125         movhu   (CHCTR),d0
 126         btst    CHCTR_DCEN,d0
 127         beq     mn10300_dcache_flush_inv_end
 128
 129         # hit each line in the dcache with an unconditional purge
 130         mov     DCACHE_PURGE(0,0),a1            # dcache purge request address
 131         mov     L1_CACHE_NWAYS*L1_CACHE_NENTRIES,d1  # total number of entries
 132
 133 mn10300_dcache_flush_inv_loop:
 134         mov     (a1),d0                         # unconditional purge
 135
 136         add     L1_CACHE_BYTES,a1
 137         add     -1,d1
 138         bne     mn10300_dcache_flush_inv_loop
 139
 140 mn10300_dcache_flush_inv_end:
 141         ret     [],0
 142
 143 ###############################################################################
 144 #
 145 # void mn10300_dcache_flush_inv_page(unsigned start)
 146 # void mn10300_dcache_flush_inv_range(unsigned start, unsigned end)
 147 # void mn10300_dcache_flush_inv_range2(unsigned start, unsigned size)
 148 # Flush and invalidate a range of addresses on a page in the dcache
 149 #
 150 ###############################################################################
 151         ALIGN
 152 mn10300_dcache_flush_inv_page:
 153         mov     PAGE_SIZE,d1
 154 mn10300_dcache_flush_inv_range2:
 155         add     d0,d1
 156 mn10300_dcache_flush_inv_range:
 157         movm    [d2,d3],(sp)
 158         movhu   (CHCTR),d2
 159         btst    CHCTR_DCEN,d2
 160         beq     mn10300_dcache_flush_inv_range_end
 161
 162         and     L1_CACHE_TAG_ADDRESS|L1_CACHE_TAG_ENTRY,d0      # round start
 163                                                                 # addr down
 164         mov     d0,a1
 165
 166         add     L1_CACHE_BYTES,d1                       # round end addr up
 167         and     L1_CACHE_TAG_ADDRESS|L1_CACHE_TAG_ENTRY,d1
 168
 169         # write a request to flush and invalidate all instances of an address
 170         # from the cache
 171         mov     DCACHE_PURGE(0,0),a0
 172         mov     a1,d0
 173         and     L1_CACHE_TAG_ENTRY,d0
 174         add     d0,a0                           # starting dcache purge control
 175                                                 # reg address
 176
 177         sub     a1,d1
 178         lsr     L1_CACHE_SHIFT,d1               # total number of entries to
 179                                                 # examine
 180
 181 mn10300_dcache_flush_inv_range_loop:
 182         mov     a1,(L1_CACHE_WAYDISP*0,a0)      # conditionally purge this line
 183                                                 # in all ways
 184
 185         add     L1_CACHE_BYTES,a0
 186         add     L1_CACHE_BYTES,a1
 187         and     ~L1_CACHE_WAYDISP,a0            # make sure way stay on way 0
 188         add     -1,d1
 189         bne     mn10300_dcache_flush_inv_range_loop
 190
 191 mn10300_dcache_flush_inv_range_end:
 192         ret     [d2,d3],8