tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Copyright (C) 1998, 1999, 2000 by Ralf Baechle
7 * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
8 */
9#include <asm/asm.h>
10#include <asm/asm-offsets.h>
11#include <asm/regdef.h>
12
13#define EX(insn,reg,addr,handler) \
149: insn reg, addr; \
15 .section __ex_table,"a"; \
16 PTR 9b, handler; \
17 .previous
18
19 .macro f_fill64 dst, offset, val, fixup
20 EX(LONG_S, \val, (\offset + 0 * LONGSIZE)(\dst), \fixup)
21 EX(LONG_S, \val, (\offset + 1 * LONGSIZE)(\dst), \fixup)
22 EX(LONG_S, \val, (\offset + 2 * LONGSIZE)(\dst), \fixup)
23 EX(LONG_S, \val, (\offset + 3 * LONGSIZE)(\dst), \fixup)
24 EX(LONG_S, \val, (\offset + 4 * LONGSIZE)(\dst), \fixup)
25 EX(LONG_S, \val, (\offset + 5 * LONGSIZE)(\dst), \fixup)
26 EX(LONG_S, \val, (\offset + 6 * LONGSIZE)(\dst), \fixup)
27 EX(LONG_S, \val, (\offset + 7 * LONGSIZE)(\dst), \fixup)
28 .endm
29
30/*
31 * memset(void *s, int c, size_t n)
32 *
33 * a0: start of area to clear
34 * a1: char to fill with
35 * a2: size of area to clear
36 */
37 .set noreorder
38 .align 5
39LEAF(memset)
40 beqz a1, 1f
41 move v0, a0 /* result */
42
43 andi a1, 0xff /* spread fillword */
44 dsll t1, a1, 8
45 or a1, t1
46 dsll t1, a1, 16
47 or a1, t1
48 dsll t1, a1, 32
49 or a1, t1
501:
51
52FEXPORT(__bzero)
53 sltiu t0, a2, LONGSIZE /* very small region? */
54 bnez t0, small_memset
55 andi t0, a0, LONGMASK /* aligned? */
56
57 beqz t0, 1f
58 PTR_SUBU t0, LONGSIZE /* alignment in bytes */
59
60#ifdef __MIPSEB__
61 EX(sdl, a1, (a0), first_fixup) /* make dword aligned */
62#endif
63#ifdef __MIPSEL__
64 EX(sdr, a1, (a0), first_fixup) /* make dword aligned */
65#endif
66 PTR_SUBU a0, t0 /* long align ptr */
67 PTR_ADDU a2, t0 /* correct size */
68
691: ori t1, a2, 0x3f /* # of full blocks */
70 xori t1, 0x3f
71 beqz t1, memset_partial /* no block to fill */
72 andi t0, a2, 0x38
73
74 PTR_ADDU t1, a0 /* end address */
75 .set reorder
761: PTR_ADDIU a0, 64
77 f_fill64 a0, -64, a1, fwd_fixup
78 bne t1, a0, 1b
79 .set noreorder
80
81memset_partial:
82 PTR_LA t1, 2f /* where to start */
83 .set noat
84 dsrl AT, t0, 1
85 PTR_SUBU t1, AT
86 .set noat
87 jr t1
88 PTR_ADDU a0, t0 /* dest ptr */
89
90 .set push
91 .set noreorder
92 .set nomacro
93 f_fill64 a0, -64, a1, partial_fixup /* ... but first do longs ... */
942: .set pop
95 andi a2, LONGMASK /* At most one long to go */
96
97 beqz a2, 1f
98 PTR_ADDU a0, a2 /* What's left */
99#ifdef __MIPSEB__
100 EX(sdr, a1, -1(a0), last_fixup)
101#endif
102#ifdef __MIPSEL__
103 EX(sdl, a1, -1(a0), last_fixup)
104#endif
1051: jr ra
106 move a2, zero
107
108small_memset:
109 beqz a2, 2f
110 PTR_ADDU t1, a0, a2
111
1121: PTR_ADDIU a0, 1 /* fill bytewise */
113 bne t1, a0, 1b
114 sb a1, -1(a0)
115
1162: jr ra /* done */
117 move a2, zero
118 END(memset)
119
120first_fixup:
121 jr ra
122 nop
123
124fwd_fixup:
125 PTR_L t0, TI_TASK($28)
126 LONG_L t0, THREAD_BUADDR(t0)
127 andi a2, 0x3f
128 LONG_ADDU a2, t1
129 jr ra
130 LONG_SUBU a2, t0
131
132partial_fixup:
133 PTR_L t0, TI_TASK($28)
134 LONG_L t0, THREAD_BUADDR(t0)
135 andi a2, LONGMASK
136 LONG_ADDU a2, t1
137 jr ra
138 LONG_SUBU a2, t0
139
140last_fixup:
141 jr ra
142 andi v1, a2, LONGMASK