xref: /openbmc/linux/arch/sparc/lib/memset.S (revision 6d99a79c) 
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:	ba 30f;					\
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)
71	.globl	__memset_start, __memset_end
72__memset_start:
73memset:
74	mov	%o0, %g1
75	mov	1, %g4
76	and	%o1, 0xff, %g3
77	sll	%g3, 8, %g2
78	or	%g3, %g2, %g3
79	sll	%g3, 16, %g2
80	or	%g3, %g2, %g3
81	b	1f
82	 mov	%o2, %o1
833:
84	cmp	%o2, 3
85	be	2f
86	 EX(stb	%g3, [%o0], sub %o1, 0)
87
88	cmp	%o2, 2
89	be	2f
90	 EX(stb	%g3, [%o0 + 0x01], sub %o1, 1)
91
92	EX(stb	%g3, [%o0 + 0x02], sub %o1, 2)
932:
94	sub	%o2, 4, %o2
95	add	%o1, %o2, %o1
96	b	4f
97	 sub	%o0, %o2, %o0
98
99__bzero:
100	clr	%g4
101	mov	%g0, %g3
1021:
103	cmp	%o1, 7
104	bleu	7f
105	 andcc	%o0, 3, %o2
106
107	bne	3b
1084:
109	 andcc	%o0, 4, %g0
110
111	be	2f
112	 mov	%g3, %g2
113
114	EX(st	%g3, [%o0], sub %o1, 0)
115	sub	%o1, 4, %o1
116	add	%o0, 4, %o0
1172:
118	andcc	%o1, 0xffffff80, %o3	! Now everything is 8 aligned and o1 is len to run
119	be	9f
120	 andcc	%o1, 0x78, %o2
12110:
122	ZERO_BIG_BLOCK(%o0, 0x00, %g2)
123	subcc	%o3, 128, %o3
124	ZERO_BIG_BLOCK(%o0, 0x40, %g2)
12511:
126	EXT(10b, 11b, 20f)
127	bne	10b
128	 add	%o0, 128, %o0
129
130	orcc	%o2, %g0, %g0
1319:
132	be	13f
133	 andcc	%o1, 7, %o1
134
135	srl	%o2, 1, %o3
136	set	13f, %o4
137	sub	%o4, %o3, %o4
138	jmp	%o4
139	 add	%o0, %o2, %o0
140
14112:
142	ZERO_LAST_BLOCKS(%o0, 0x48, %g2)
143	ZERO_LAST_BLOCKS(%o0, 0x08, %g2)
14413:
145	be	8f
146	 andcc	%o1, 4, %g0
147
148	be	1f
149	 andcc	%o1, 2, %g0
150
151	EX(st	%g3, [%o0], and %o1, 7)
152	add	%o0, 4, %o0
1531:
154	be	1f
155	 andcc	%o1, 1, %g0
156
157	EX(sth	%g3, [%o0], and %o1, 3)
158	add	%o0, 2, %o0
1591:
160	bne,a	8f
161	 EX(stb	%g3, [%o0], and %o1, 1)
1628:
163	b	0f
164	 nop
1657:
166	be	13b
167	 orcc	%o1, 0, %g0
168
169	be	0f
1708:
171	 add	%o0, 1, %o0
172	subcc	%o1, 1, %o1
173	bne	8b
174	 EX(stb	%g3, [%o0 - 1], add %o1, 1)
1750:
176	andcc	%g4, 1, %g0
177	be	5f
178	 nop
179	retl
180	 mov	%g1, %o0
1815:
182	retl
183	 clr	%o0
184__memset_end:
185
186	.section .fixup,#alloc,#execinstr
187	.align	4
18820:
189	cmp	%g2, 8
190	bleu	1f
191	 and	%o1, 0x7f, %o1
192	sub	%g2, 9, %g2
193	add	%o3, 64, %o3
1941:
195	sll	%g2, 3, %g2
196	add	%o3, %o1, %o0
197	b 30f
198	 sub	%o0, %g2, %o0
19921:
200	mov	8, %o0
201	and	%o1, 7, %o1
202	sub	%o0, %g2, %o0
203	sll	%o0, 3, %o0
204	b 30f
205	 add	%o0, %o1, %o0
20630:
207/* %o4 is faulting address, %o5 is %pc where fault occurred */
208	save	%sp, -104, %sp
209	mov	%i5, %o0
210	mov	%i7, %o1
211	call	lookup_fault
212	 mov	%i4, %o2
213	ret
214	 restore
215
216	.globl __bzero_end
217__bzero_end:
218