| Paul Mundt | 510c72ad | 2006-11-27 12:06:26 +0900 | [diff] [blame] | 1 | /* |
| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2 | * __clear_user_page, __clear_user, clear_page implementation of SuperH |
| 3 | * |
| 4 | * Copyright (C) 2001 Kaz Kojima |
| 5 | * Copyright (C) 2001, 2002 Niibe Yutaka |
| Paul Mundt | 510c72ad | 2006-11-27 12:06:26 +0900 | [diff] [blame] | 6 | * Copyright (C) 2006 Paul Mundt |
| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 7 | */ |
| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 8 | #include <linux/linkage.h> |
| Paul Mundt | 510c72ad | 2006-11-27 12:06:26 +0900 | [diff] [blame] | 9 | #include <asm/page.h> |
| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 10 | |
| 11 | /* |
| Paul Mundt | 0dcb957 | 2007-11-23 13:55:02 +0900 | [diff] [blame] | 12 | * clear_page |
| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 13 | * @to: P1 address |
| 14 | * |
| Paul Mundt | 0dcb957 | 2007-11-23 13:55:02 +0900 | [diff] [blame] | 15 | * void clear_page(void *to) |
| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 16 | */ |
| 17 | |
| 18 | /* |
| 19 | * r0 --- scratch |
| 20 | * r4 --- to |
| Paul Mundt | 510c72ad | 2006-11-27 12:06:26 +0900 | [diff] [blame] | 21 | * r5 --- to + PAGE_SIZE |
| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 22 | */ |
| Paul Mundt | 0dcb957 | 2007-11-23 13:55:02 +0900 | [diff] [blame] | 23 | ENTRY(clear_page) |
| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 24 | mov r4,r5 |
| Paul Mundt | 510c72ad | 2006-11-27 12:06:26 +0900 | [diff] [blame] | 25 | mov.l .Llimit,r0 |
| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 26 | add r0,r5 |
| 27 | mov #0,r0 |
| 28 | ! |
| 29 | 1: |
| 30 | #if defined(CONFIG_CPU_SH3) |
| 31 | mov.l r0,@r4 |
| 32 | #elif defined(CONFIG_CPU_SH4) |
| 33 | movca.l r0,@r4 |
| 34 | mov r4,r1 |
| 35 | #endif |
| 36 | add #32,r4 |
| 37 | mov.l r0,@-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 | #if defined(CONFIG_CPU_SH4) |
| 45 | ocbwb @r1 |
| 46 | #endif |
| 47 | cmp/eq r5,r4 |
| 48 | bf/s 1b |
| 49 | add #28,r4 |
| 50 | ! |
| 51 | rts |
| 52 | nop |
| Paul Mundt | 325df7f | 2007-11-30 16:34:26 +0900 | [diff] [blame^] | 53 | |
| 54 | .balign 4 |
| Paul Mundt | 510c72ad | 2006-11-27 12:06:26 +0900 | [diff] [blame] | 55 | .Llimit: .long (PAGE_SIZE-28) |
| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 56 | |
| 57 | ENTRY(__clear_user) |
| 58 | ! |
| 59 | mov #0, r0 |
| 60 | mov #0xe0, r1 ! 0xffffffe0 |
| 61 | ! |
| 62 | ! r4..(r4+31)&~32 -------- not aligned [ Area 0 ] |
| 63 | ! (r4+31)&~32..(r4+r5)&~32 -------- aligned [ Area 1 ] |
| 64 | ! (r4+r5)&~32..r4+r5 -------- not aligned [ Area 2 ] |
| 65 | ! |
| 66 | ! Clear area 0 |
| 67 | mov r4, r2 |
| 68 | ! |
| 69 | tst r1, r5 ! length < 32 |
| 70 | bt .Larea2 ! skip to remainder |
| 71 | ! |
| 72 | add #31, r2 |
| 73 | and r1, r2 |
| 74 | cmp/eq r4, r2 |
| 75 | bt .Larea1 |
| 76 | mov r2, r3 |
| 77 | sub r4, r3 |
| 78 | mov r3, r7 |
| 79 | mov r4, r2 |
| 80 | ! |
| 81 | .L0: dt r3 |
| 82 | 0: mov.b r0, @r2 |
| 83 | bf/s .L0 |
| 84 | add #1, r2 |
| 85 | ! |
| 86 | sub r7, r5 |
| 87 | mov r2, r4 |
| 88 | .Larea1: |
| 89 | mov r4, r3 |
| 90 | add r5, r3 |
| 91 | and r1, r3 |
| 92 | cmp/hi r2, r3 |
| 93 | bf .Larea2 |
| 94 | ! |
| 95 | ! Clear area 1 |
| 96 | #if defined(CONFIG_CPU_SH4) |
| 97 | 1: movca.l r0, @r2 |
| 98 | #else |
| 99 | 1: mov.l r0, @r2 |
| 100 | #endif |
| 101 | add #4, r2 |
| 102 | 2: mov.l r0, @r2 |
| 103 | add #4, r2 |
| 104 | 3: mov.l r0, @r2 |
| 105 | add #4, r2 |
| 106 | 4: mov.l r0, @r2 |
| 107 | add #4, r2 |
| 108 | 5: mov.l r0, @r2 |
| 109 | add #4, r2 |
| 110 | 6: mov.l r0, @r2 |
| 111 | add #4, r2 |
| 112 | 7: mov.l r0, @r2 |
| 113 | add #4, r2 |
| 114 | 8: mov.l r0, @r2 |
| 115 | add #4, r2 |
| 116 | cmp/hi r2, r3 |
| 117 | bt/s 1b |
| 118 | nop |
| 119 | ! |
| 120 | ! Clear area 2 |
| 121 | .Larea2: |
| 122 | mov r4, r3 |
| 123 | add r5, r3 |
| 124 | cmp/hs r3, r2 |
| 125 | bt/s .Ldone |
| 126 | sub r2, r3 |
| 127 | .L2: dt r3 |
| 128 | 9: mov.b r0, @r2 |
| 129 | bf/s .L2 |
| 130 | add #1, r2 |
| 131 | ! |
| 132 | .Ldone: rts |
| 133 | mov #0, r0 ! return 0 as normal return |
| 134 | |
| 135 | ! return the number of bytes remained |
| 136 | .Lbad_clear_user: |
| 137 | mov r4, r0 |
| 138 | add r5, r0 |
| 139 | rts |
| 140 | sub r2, r0 |
| 141 | |
| 142 | .section __ex_table,"a" |
| 143 | .align 2 |
| 144 | .long 0b, .Lbad_clear_user |
| 145 | .long 1b, .Lbad_clear_user |
| 146 | .long 2b, .Lbad_clear_user |
| 147 | .long 3b, .Lbad_clear_user |
| 148 | .long 4b, .Lbad_clear_user |
| 149 | .long 5b, .Lbad_clear_user |
| 150 | .long 6b, .Lbad_clear_user |
| 151 | .long 7b, .Lbad_clear_user |
| 152 | .long 8b, .Lbad_clear_user |
| 153 | .long 9b, .Lbad_clear_user |
| 154 | .previous |