xref: /openbmc/linux/arch/sparc/lib/memset.S (revision 7559e757) 
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 STORE(source, base, offset, n)		\
3198: 	std source, [base + offset + n];	\
32	.section .fixup,ALLOC,EXECINSTR;	\
33	.align	4;				\
3499:	ba 30f;					\
35	 sub %o3, n - offset, %o3;		\
36	.section __ex_table,ALLOC;		\
37	.align	4;				\
38	.word	98b, 99b;			\
39	.text;					\
40	.align	4;
41
42#define STORE_LAST(source, base, offset, n)	\
43	EX(std source, [base - offset - n],	\
44	   add %o1, offset + n);
45
46/* Please don't change these macros, unless you change the logic
47 * in the .fixup section below as well.
48 * Store 64 bytes at (BASE + OFFSET) using value SOURCE. */
49#define ZERO_BIG_BLOCK(base, offset, source)	\
50	STORE(source, base, offset, 0x00);	\
51	STORE(source, base, offset, 0x08);	\
52	STORE(source, base, offset, 0x10);	\
53	STORE(source, base, offset, 0x18);	\
54	STORE(source, base, offset, 0x20);	\
55	STORE(source, base, offset, 0x28);	\
56	STORE(source, base, offset, 0x30);	\
57	STORE(source, base, offset, 0x38);
58
59#define ZERO_LAST_BLOCKS(base, offset, source)	\
60	STORE_LAST(source, base, offset, 0x38);	\
61	STORE_LAST(source, base, offset, 0x30); \
62	STORE_LAST(source, base, offset, 0x28);	\
63	STORE_LAST(source, base, offset, 0x20);	\
64	STORE_LAST(source, base, offset, 0x18);	\
65	STORE_LAST(source, base, offset, 0x10);	\
66	STORE_LAST(source, base, offset, 0x08);	\
67	STORE_LAST(source, base, offset, 0x00);
68
69	.text
70	.align 4
71
72        .globl  __bzero_begin
73__bzero_begin:
74
75	.globl	__bzero
76	.type	__bzero,#function
77	.globl	memset
78	EXPORT_SYMBOL(__bzero)
79	EXPORT_SYMBOL(memset)
80memset:
81	mov	%o0, %g1
82	mov	1, %g4
83	and	%o1, 0xff, %g3
84	sll	%g3, 8, %g2
85	or	%g3, %g2, %g3
86	sll	%g3, 16, %g2
87	or	%g3, %g2, %g3
88	b	1f
89	 mov	%o2, %o1
903:
91	cmp	%o2, 3
92	be	2f
93	 EX(stb	%g3, [%o0], sub %o1, 0)
94
95	cmp	%o2, 2
96	be	2f
97	 EX(stb	%g3, [%o0 + 0x01], sub %o1, 1)
98
99	EX(stb	%g3, [%o0 + 0x02], sub %o1, 2)
1002:
101	sub	%o2, 4, %o2
102	add	%o1, %o2, %o1
103	b	4f
104	 sub	%o0, %o2, %o0
105
106__bzero:
107	clr	%g4
108	mov	%g0, %g3
1091:
110	cmp	%o1, 7
111	bleu	7f
112	 andcc	%o0, 3, %o2
113
114	bne	3b
1154:
116	 andcc	%o0, 4, %g0
117
118	be	2f
119	 mov	%g3, %g2
120
121	EX(st	%g3, [%o0], sub %o1, 0)
122	sub	%o1, 4, %o1
123	add	%o0, 4, %o0
1242:
125	andcc	%o1, 0xffffff80, %o3	! Now everything is 8 aligned and o1 is len to run
126	be	9f
127	 andcc	%o1, 0x78, %o2
12810:
129	ZERO_BIG_BLOCK(%o0, 0x00, %g2)
130	subcc	%o3, 128, %o3
131	ZERO_BIG_BLOCK(%o0, 0x40, %g2)
132	bne	10b
133	 add	%o0, 128, %o0
134
135	orcc	%o2, %g0, %g0
1369:
137	be	13f
138	 andcc	%o1, 7, %o1
139
140	srl	%o2, 1, %o3
141	set	13f, %o4
142	sub	%o4, %o3, %o4
143	jmp	%o4
144	 add	%o0, %o2, %o0
145
146	ZERO_LAST_BLOCKS(%o0, 0x48, %g2)
147	ZERO_LAST_BLOCKS(%o0, 0x08, %g2)
14813:
149	be	8f
150	 andcc	%o1, 4, %g0
151
152	be	1f
153	 andcc	%o1, 2, %g0
154
155	EX(st	%g3, [%o0], and %o1, 7)
156	add	%o0, 4, %o0
1571:
158	be	1f
159	 andcc	%o1, 1, %g0
160
161	EX(sth	%g3, [%o0], and %o1, 3)
162	add	%o0, 2, %o0
1631:
164	bne,a	8f
165	 EX(stb	%g3, [%o0], and %o1, 1)
1668:
167	b	0f
168	 nop
1697:
170	be	13b
171	 orcc	%o1, 0, %g0
172
173	be	0f
1748:
175	 add	%o0, 1, %o0
176	subcc	%o1, 1, %o1
177	bne	8b
178	 EX(stb	%g3, [%o0 - 1], add %o1, 1)
1790:
180	andcc	%g4, 1, %g0
181	be	5f
182	 nop
183	retl
184	 mov	%g1, %o0
1855:
186	retl
187	 clr	%o0
188
189	.section .fixup,#alloc,#execinstr
190	.align	4
19130:
192	and	%o1, 0x7f, %o1
193	retl
194	 add	%o3, %o1, %o0
195
196	.globl __bzero_end
197__bzero_end:
198