arch/m32r/mm/page.S

   1 /*
   2  *  linux/arch/m32r/mm/page.S
   3  *
   4  *  Clear/Copy page with CPU
   5  *
   6  *  Copyright (C) 2004  The Free Software Initiative of Japan
   7  *
   8  *  Written by Niibe Yutaka
   9  *
  10  * This file is subject to the terms and conditions of the GNU General Public
  11  * License.  See the file "COPYING" in the main directory of this archive
  12  * for more details.
  13  *
  14  */
  15         .text
  16         .global copy_page
  17         /*
  18          * copy_page (to, from)
  19          *
  20          * PAGE_SIZE = 4096-byte
  21          * Cache line = 16-byte
  22          * 16 * 256
  23          */
  24         .align  4
  25 copy_page:
  26         ldi     r2, #255
  27         ld      r3, @r0         /* cache line allocate */
  28         ld      r4, @r1+
  29         ld      r5, @r1+
  30         ld      r6, @r1+
  31         ld      r7, @r1+
  32         .fillinsn
  33 0:
  34         st      r4, @r0
  35         st      r5, @+r0
  36         st      r6, @+r0
  37         st      r7, @+r0
  38         ld      r4, @r1+
  39         addi    r0, #4
  40         ld      r5, @r1+
  41         ld      r6, @r1+
  42         ld      r7, @r1+
  43         ld      r3, @r0         /* cache line allocate */
  44         addi    r2, #-1
  45         bnez    r2, 0b
  46
  47         st      r4, @r0
  48         st      r5, @+r0
  49         st      r6, @+r0
  50         st      r7, @+r0
  51         jmp     r14
  52
  53         .text
  54         .global clear_page
  55         /*
  56          * clear_page (to)
  57          *
  58          * PAGE_SIZE = 4096-byte
  59          * Cache line = 16-byte
  60          * 16 * 256
  61          */
  62         .align  4
  63 clear_page:
  64         ldi     r2, #255
  65         ldi     r4, #0
  66         ld      r3, @r0         /* cache line allocate */
  67         .fillinsn
  68 0:
  69         st      r4, @r0
  70         st      r4, @+r0
  71         st      r4, @+r0
  72         st      r4, @+r0
  73         addi    r0, #4
  74         ld      r3, @r0         /* cache line allocate */
  75         addi    r2, #-1
  76         bnez    r2, 0b
  77
  78         st      r4, @r0
  79         st      r4, @+r0
  80         st      r4, @+r0
  81         st      r4, @+r0
  82         jmp     r14