xref: /linux/arch/sparc/lib/blockops.S (revision 1553a1c48281243359a9529a10ddb551f3b967ab)
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