arch/sh/mm/clear_page.S

   1 /* $Id: clear_page.S,v 1.13 2003/08/25 17:03:10 lethal Exp $
   2  *
   3  * __clear_user_page, __clear_user, clear_page implementation of SuperH
   4  *
   5  * Copyright (C) 2001  Kaz Kojima
   6  * Copyright (C) 2001, 2002  Niibe Yutaka
   7  *
   8  */
   9 #include <linux/config.h>
  10 #include <linux/linkage.h>
  11
  12 /*
  13  * clear_page_slow
  14  * @to: P1 address
  15  *
  16  * void clear_page_slow(void *to)
  17  */
  18
  19 /*
  20  * r0 --- scratch
  21  * r4 --- to
  22  * r5 --- to + 4096
  23  */
  24 ENTRY(clear_page_slow)
  25         mov     r4,r5
  26         mov.w   .Llimit,r0
  27         add     r0,r5
  28         mov     #0,r0
  29         !
  30 1:
  31 #if defined(CONFIG_CPU_SH3)
  32         mov.l   r0,@r4
  33 #elif defined(CONFIG_CPU_SH4)
  34         movca.l r0,@r4
  35         mov     r4,r1
  36 #endif
  37         add     #32,r4
  38         mov.l   r0,@-r4
  39         mov.l   r0,@-r4
  40         mov.l   r0,@-r4
  41         mov.l   r0,@-r4
  42         mov.l   r0,@-r4
  43         mov.l   r0,@-r4
  44         mov.l   r0,@-r4
  45 #if defined(CONFIG_CPU_SH4)
  46         ocbwb   @r1
  47 #endif
  48         cmp/eq  r5,r4
  49         bf/s    1b
  50          add    #28,r4
  51         !
  52         rts
  53          nop
  54 .Llimit:        .word   (4096-28)
  55
  56 ENTRY(__clear_user)
  57         !
  58         mov     #0, r0
  59         mov     #0xe0, r1       ! 0xffffffe0
  60         !
  61         ! r4..(r4+31)&~32          -------- not aligned [ Area 0 ]
  62         ! (r4+31)&~32..(r4+r5)&~32 -------- aligned     [ Area 1 ]
  63         ! (r4+r5)&~32..r4+r5       -------- not aligned [ Area 2 ]
  64         !
  65         ! Clear area 0
  66         mov     r4, r2
  67         !
  68         tst     r1, r5          ! length < 32
  69         bt      .Larea2         ! skip to remainder
  70         !
  71         add     #31, r2
  72         and     r1, r2
  73         cmp/eq  r4, r2
  74         bt      .Larea1
  75         mov     r2, r3
  76         sub     r4, r3
  77         mov     r3, r7
  78         mov     r4, r2
  79         !
  80 .L0:    dt      r3
  81 0:      mov.b   r0, @r2
  82         bf/s    .L0
  83          add    #1, r2
  84         !
  85         sub     r7, r5
  86         mov     r2, r4
  87 .Larea1:
  88         mov     r4, r3
  89         add     r5, r3
  90         and     r1, r3
  91         cmp/hi  r2, r3
  92         bf      .Larea2
  93         !
  94         ! Clear area 1
  95 #if defined(CONFIG_CPU_SH4)
  96 1:      movca.l r0, @r2
  97 #else
  98 1:      mov.l   r0, @r2
  99 #endif
 100         add     #4, r2
 101 2:      mov.l   r0, @r2
 102         add     #4, r2
 103 3:      mov.l   r0, @r2
 104         add     #4, r2
 105 4:      mov.l   r0, @r2
 106         add     #4, r2
 107 5:      mov.l   r0, @r2
 108         add     #4, r2
 109 6:      mov.l   r0, @r2
 110         add     #4, r2
 111 7:      mov.l   r0, @r2
 112         add     #4, r2
 113 8:      mov.l   r0, @r2
 114         add     #4, r2
 115         cmp/hi  r2, r3
 116         bt/s    1b
 117          nop
 118         !
 119         ! Clear area 2
 120 .Larea2:
 121         mov     r4, r3
 122         add     r5, r3
 123         cmp/hs  r3, r2
 124         bt/s    .Ldone
 125          sub    r2, r3
 126 .L2:    dt      r3
 127 9:      mov.b   r0, @r2
 128         bf/s    .L2
 129          add    #1, r2
 130         !
 131 .Ldone: rts
 132          mov    #0, r0  ! return 0 as normal return
 133
 134         ! return the number of bytes remained
 135 .Lbad_clear_user:
 136         mov     r4, r0
 137         add     r5, r0
 138         rts
 139          sub    r2, r0
 140
 141 .section __ex_table,"a"
 142         .align 2
 143         .long   0b, .Lbad_clear_user
 144         .long   1b, .Lbad_clear_user
 145         .long   2b, .Lbad_clear_user
 146         .long   3b, .Lbad_clear_user
 147         .long   4b, .Lbad_clear_user
 148         .long   5b, .Lbad_clear_user
 149         .long   6b, .Lbad_clear_user
 150         .long   7b, .Lbad_clear_user
 151         .long   8b, .Lbad_clear_user
 152         .long   9b, .Lbad_clear_user
 153 .previous
 154
 155 #if defined(CONFIG_CPU_SH4)
 156 /*
 157  * __clear_user_page
 158  * @to: P3 address (with same color)
 159  * @orig_to: P1 address
 160  *
 161  * void __clear_user_page(void *to, void *orig_to)
 162  */
 163
 164 /*
 165  * r0 --- scratch
 166  * r4 --- to
 167  * r5 --- orig_to
 168  * r6 --- to + 4096
 169  */
 170 ENTRY(__clear_user_page)
 171         mov.w   .L4096,r0
 172         mov     r4,r6
 173         add     r0,r6
 174         mov     #0,r0
 175         !
 176 1:      ocbi    @r5
 177         add     #32,r5
 178         movca.l r0,@r4
 179         mov     r4,r1
 180         add     #32,r4
 181         mov.l   r0,@-r4
 182         mov.l   r0,@-r4
 183         mov.l   r0,@-r4
 184         mov.l   r0,@-r4
 185         mov.l   r0,@-r4
 186         mov.l   r0,@-r4
 187         mov.l   r0,@-r4
 188         add     #28,r4
 189         cmp/eq  r6,r4
 190         bf/s    1b
 191          ocbwb  @r1
 192         !
 193         rts
 194          nop
 195 .L4096: .word   4096
 196
 197 ENTRY(__flush_cache_4096)
 198         mov.l   1f,r3
 199         add     r6,r3
 200         mov     r4,r0
 201         mov     #64,r2
 202         shll    r2
 203         mov     #64,r6
 204         jmp     @r3
 205          mov    #96,r7
 206         .align  2
 207 1:      .long   2f
 208 2:
 209         .rept   32
 210         mov.l   r5,@r0
 211         mov.l   r5,@(32,r0)
 212         mov.l   r5,@(r0,r6)
 213         mov.l   r5,@(r0,r7)
 214         add     r2,r5
 215         add     r2,r0
 216         .endr
 217         nop
 218         nop
 219         nop
 220         nop
 221         nop
 222         nop
 223         nop
 224         rts
 225          nop
 226
 227 ENTRY(__flush_dcache_all)
 228         mov.l   2f,r0
 229         mov.l   3f,r4
 230         and     r0,r4           ! r4 = (unsigned long)&empty_zero_page[0] & ~0xffffc000
 231         stc     sr,r1           ! save SR
 232         mov.l   4f,r2
 233         or      r1,r2
 234         mov     #32,r3
 235         shll2   r3
 236 1:
 237         ldc     r2,sr           ! set BL bit
 238         movca.l r0,@r4
 239         ocbi    @r4
 240         add     #32,r4
 241         movca.l r0,@r4
 242         ocbi    @r4
 243         add     #32,r4
 244         movca.l r0,@r4
 245         ocbi    @r4
 246         add     #32,r4
 247         movca.l r0,@r4
 248         ocbi    @r4
 249         ldc     r1,sr           ! restore SR
 250         dt      r3
 251         bf/s    1b
 252          add    #32,r4
 253
 254         rts
 255          nop
 256         .align  2
 257 2:      .long   0xffffc000
 258 3:      .long   empty_zero_page
 259 4:      .long   0x10000000      ! BL bit
 260
 261 /* __flush_cache_4096_all(unsigned long addr) */
 262 ENTRY(__flush_cache_4096_all)
 263         mov.l   2f,r0
 264         mov.l   3f,r2
 265         and     r0,r2
 266         or      r2,r4           ! r4 = addr | (unsigned long)&empty_zero_page[0] & ~0x3fff
 267         stc     sr,r1           ! save SR
 268         mov.l   4f,r2
 269         or      r1,r2
 270         mov     #32,r3
 271 1:
 272         ldc     r2,sr           ! set BL bit
 273         movca.l r0,@r4
 274         ocbi    @r4
 275         add     #32,r4
 276         movca.l r0,@r4
 277         ocbi    @r4
 278         add     #32,r4
 279         movca.l r0,@r4
 280         ocbi    @r4
 281         add     #32,r4
 282         movca.l r0,@r4
 283         ocbi    @r4
 284         ldc     r1,sr           ! restore SR
 285         dt      r3
 286         bf/s    1b
 287          add    #32,r4
 288
 289         rts
 290          nop
 291         .align  2
 292 2:      .long   0xffffc000
 293 3:      .long   empty_zero_page
 294 4:      .long   0x10000000      ! BL bit
 295 #endif