1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * blockops.S: Common block zero optimized routines.
4 *
5 * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
6 */
7
8#include <linux/export.h>
9#include <linux/linkage.h>
10#include <asm/page.h>
11
12 /* Zero out 64 bytes of memory at (buf + offset).
13 * Assumes %g1 contains zero.
14 */
15#define BLAST_BLOCK(buf, offset) \
16 std %g0, [buf + offset + 0x38]; \
17 std %g0, [buf + offset + 0x30]; \
18 std %g0, [buf + offset + 0x28]; \
19 std %g0, [buf + offset + 0x20]; \
20 std %g0, [buf + offset + 0x18]; \
21 std %g0, [buf + offset + 0x10]; \
22 std %g0, [buf + offset + 0x08]; \
23 std %g0, [buf + offset + 0x00];
24
25 /* Copy 32 bytes of memory at (src + offset) to
26 * (dst + offset).
27 */
28#define MIRROR_BLOCK(dst, src, offset, t0, t1, t2, t3, t4, t5, t6, t7) \
29 ldd [src + offset + 0x18], t0; \
30 ldd [src + offset + 0x10], t2; \
31 ldd [src + offset + 0x08], t4; \
32 ldd [src + offset + 0x00], t6; \
33 std t0, [dst + offset + 0x18]; \
34 std t2, [dst + offset + 0x10]; \
35 std t4, [dst + offset + 0x08]; \
36 std t6, [dst + offset + 0x00];
37
38 /* Profiling evidence indicates that memset() is
39 * commonly called for blocks of size PAGE_SIZE,
40 * and (2 * PAGE_SIZE) (for kernel stacks)
41 * and with a second arg of zero. We assume in
42 * all of these cases that the buffer is aligned
43 * on at least an 8 byte boundary.
44 *
45 * Therefore we special case them to make them
46 * as fast as possible.
47 */
48
49 .text
50ENTRY(bzero_1page)
51/* NOTE: If you change the number of insns of this routine, please check
52 * arch/sparc/mm/hypersparc.S */
53 /* %o0 = buf */
54 or %g0, %g0, %g1
55 or %o0, %g0, %o1
56 or %g0, (PAGE_SIZE >> 8), %g2
571:
58 BLAST_BLOCK(%o0, 0x00)
59 BLAST_BLOCK(%o0, 0x40)
60 BLAST_BLOCK(%o0, 0x80)
61 BLAST_BLOCK(%o0, 0xc0)
62 subcc %g2, 1, %g2
63 bne 1b
64 add %o0, 0x100, %o0
65
66 retl
67 nop
68ENDPROC(bzero_1page)
69EXPORT_SYMBOL(bzero_1page)
70
71ENTRY(__copy_1page)
72/* NOTE: If you change the number of insns of this routine, please check
73 * arch/sparc/mm/hypersparc.S */
74 /* %o0 = dst, %o1 = src */
75 or %g0, (PAGE_SIZE >> 8), %g1
761:
77 MIRROR_BLOCK(%o0, %o1, 0x00, %o2, %o3, %o4, %o5, %g2, %g3, %g4, %g5)
78 MIRROR_BLOCK(%o0, %o1, 0x20, %o2, %o3, %o4, %o5, %g2, %g3, %g4, %g5)
79 MIRROR_BLOCK(%o0, %o1, 0x40, %o2, %o3, %o4, %o5, %g2, %g3, %g4, %g5)
80 MIRROR_BLOCK(%o0, %o1, 0x60, %o2, %o3, %o4, %o5, %g2, %g3, %g4, %g5)
81 MIRROR_BLOCK(%o0, %o1, 0x80, %o2, %o3, %o4, %o5, %g2, %g3, %g4, %g5)
82 MIRROR_BLOCK(%o0, %o1, 0xa0, %o2, %o3, %o4, %o5, %g2, %g3, %g4, %g5)
83 MIRROR_BLOCK(%o0, %o1, 0xc0, %o2, %o3, %o4, %o5, %g2, %g3, %g4, %g5)
84 MIRROR_BLOCK(%o0, %o1, 0xe0, %o2, %o3, %o4, %o5, %g2, %g3, %g4, %g5)
85 subcc %g1, 1, %g1
86 add %o0, 0x100, %o0
87 bne 1b
88 add %o1, 0x100, %o1
89
90 retl
91 nop
92ENDPROC(__copy_1page)
93EXPORT_SYMBOL(__copy_1page)
94

source code of linux/arch/sparc/lib/blockops.S