xref: /openbmc/linux/arch/sparc/lib/memset.S (revision 5f99d338)
1/* SPDX-License-Identifier: GPL-2.0 */
2/* linux/arch/sparc/lib/memset.S: Sparc optimized memset, bzero and clear_user code
3 * Copyright (C) 1991,1996 Free Software Foundation
4 * Copyright (C) 1996,1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
5 * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
6 *
7 * Calls to memset returns initial %o0. Calls to bzero returns 0, if ok, and
8 * number of bytes not yet set if exception occurs and we were called as
9 * clear_user.
10 */
11
12#include <asm/ptrace.h>
13#include <asm/export.h>
14
15/* Work around cpp -rob */
16#define ALLOC #alloc
17#define EXECINSTR #execinstr
18#define EX(x,y,a,b) 				\
1998: 	x,y;					\
20	.section .fixup,ALLOC,EXECINSTR;	\
21	.align	4;				\
2299:	retl;					\
23	 a, b, %o0;				\
24	.section __ex_table,ALLOC;		\
25	.align	4;				\
26	.word	98b, 99b;			\
27	.text;					\
28	.align	4
29
30#define EXT(start,end,handler) 			\
31	.section __ex_table,ALLOC;		\
32	.align	4;				\
33	.word	start, 0, end, handler;		\
34	.text;					\
35	.align	4
36
37/* Please don't change these macros, unless you change the logic
38 * in the .fixup section below as well.
39 * Store 64 bytes at (BASE + OFFSET) using value SOURCE. */
40#define ZERO_BIG_BLOCK(base, offset, source)    \
41	std	source, [base + offset + 0x00]; \
42	std	source, [base + offset + 0x08]; \
43	std	source, [base + offset + 0x10]; \
44	std	source, [base + offset + 0x18]; \
45	std	source, [base + offset + 0x20]; \
46	std	source, [base + offset + 0x28]; \
47	std	source, [base + offset + 0x30]; \
48	std	source, [base + offset + 0x38];
49
50#define ZERO_LAST_BLOCKS(base, offset, source)	\
51	std	source, [base - offset - 0x38]; \
52	std	source, [base - offset - 0x30]; \
53	std	source, [base - offset - 0x28]; \
54	std	source, [base - offset - 0x20]; \
55	std	source, [base - offset - 0x18]; \
56	std	source, [base - offset - 0x10]; \
57	std	source, [base - offset - 0x08]; \
58	std	source, [base - offset - 0x00];
59
60	.text
61	.align 4
62
63        .globl  __bzero_begin
64__bzero_begin:
65
66	.globl	__bzero
67	.type	__bzero,#function
68	.globl	memset
69	EXPORT_SYMBOL(__bzero)
70	EXPORT_SYMBOL(memset)
71memset:
72	mov	%o0, %g1
73	mov	1, %g4
74	and	%o1, 0xff, %g3
75	sll	%g3, 8, %g2
76	or	%g3, %g2, %g3
77	sll	%g3, 16, %g2
78	or	%g3, %g2, %g3
79	b	1f
80	 mov	%o2, %o1
813:
82	cmp	%o2, 3
83	be	2f
84	 EX(stb	%g3, [%o0], sub %o1, 0)
85
86	cmp	%o2, 2
87	be	2f
88	 EX(stb	%g3, [%o0 + 0x01], sub %o1, 1)
89
90	EX(stb	%g3, [%o0 + 0x02], sub %o1, 2)
912:
92	sub	%o2, 4, %o2
93	add	%o1, %o2, %o1
94	b	4f
95	 sub	%o0, %o2, %o0
96
97__bzero:
98	clr	%g4
99	mov	%g0, %g3
1001:
101	cmp	%o1, 7
102	bleu	7f
103	 andcc	%o0, 3, %o2
104
105	bne	3b
1064:
107	 andcc	%o0, 4, %g0
108
109	be	2f
110	 mov	%g3, %g2
111
112	EX(st	%g3, [%o0], sub %o1, 0)
113	sub	%o1, 4, %o1
114	add	%o0, 4, %o0
1152:
116	andcc	%o1, 0xffffff80, %o3	! Now everything is 8 aligned and o1 is len to run
117	be	9f
118	 andcc	%o1, 0x78, %o2
11910:
120	ZERO_BIG_BLOCK(%o0, 0x00, %g2)
121	subcc	%o3, 128, %o3
122	ZERO_BIG_BLOCK(%o0, 0x40, %g2)
12311:
124	EXT(10b, 11b, 20f)
125	bne	10b
126	 add	%o0, 128, %o0
127
128	orcc	%o2, %g0, %g0
1299:
130	be	13f
131	 andcc	%o1, 7, %o1
132
133	srl	%o2, 1, %o3
134	set	13f, %o4
135	sub	%o4, %o3, %o4
136	jmp	%o4
137	 add	%o0, %o2, %o0
138
13912:
140	ZERO_LAST_BLOCKS(%o0, 0x48, %g2)
141	ZERO_LAST_BLOCKS(%o0, 0x08, %g2)
14213:
143	be	8f
144	 andcc	%o1, 4, %g0
145
146	be	1f
147	 andcc	%o1, 2, %g0
148
149	EX(st	%g3, [%o0], and %o1, 7)
150	add	%o0, 4, %o0
1511:
152	be	1f
153	 andcc	%o1, 1, %g0
154
155	EX(sth	%g3, [%o0], and %o1, 3)
156	add	%o0, 2, %o0
1571:
158	bne,a	8f
159	 EX(stb	%g3, [%o0], and %o1, 1)
1608:
161	b	0f
162	 nop
1637:
164	be	13b
165	 orcc	%o1, 0, %g0
166
167	be	0f
1688:
169	 add	%o0, 1, %o0
170	subcc	%o1, 1, %o1
171	bne	8b
172	 EX(stb	%g3, [%o0 - 1], add %o1, 1)
1730:
174	andcc	%g4, 1, %g0
175	be	5f
176	 nop
177	retl
178	 mov	%g1, %o0
1795:
180	retl
181	 clr	%o0
182
183	.section .fixup,#alloc,#execinstr
184	.align	4
18520:
186	cmp	%g2, 8
187	bleu	1f
188	 and	%o1, 0x7f, %o1
189	sub	%g2, 9, %g2
190	add	%o3, 64, %o3
1911:
192	sll	%g2, 3, %g2
193	add	%o3, %o1, %o0
194	retl
195	 sub	%o0, %g2, %o0
19621:
197	mov	8, %o0
198	and	%o1, 7, %o1
199	sub	%o0, %g2, %o0
200	sll	%o0, 3, %o0
201	retl
202	 add	%o0, %o1, %o0
203
204	.globl __bzero_end
205__bzero_end:
206