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) 				\
19 98: 	x,y;					\
20 	.section .fixup,ALLOC,EXECINSTR;	\
21 	.align	4;				\
22 99:	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:
73 memset:
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
83 3:
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)
93 2:
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
102 1:
103 	cmp	%o1, 7
104 	bleu	7f
105 	 andcc	%o0, 3, %o2
106 
107 	bne	3b
108 4:
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
117 2:
118 	andcc	%o1, 0xffffff80, %o3	! Now everything is 8 aligned and o1 is len to run
119 	be	9f
120 	 andcc	%o1, 0x78, %o2
121 10:
122 	ZERO_BIG_BLOCK(%o0, 0x00, %g2)
123 	subcc	%o3, 128, %o3
124 	ZERO_BIG_BLOCK(%o0, 0x40, %g2)
125 11:
126 	EXT(10b, 11b, 20f)
127 	bne	10b
128 	 add	%o0, 128, %o0
129 
130 	orcc	%o2, %g0, %g0
131 9:
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 
141 12:
142 	ZERO_LAST_BLOCKS(%o0, 0x48, %g2)
143 	ZERO_LAST_BLOCKS(%o0, 0x08, %g2)
144 13:
145 	EXT(12b, 13b, 21f)
146 	be	8f
147 	 andcc	%o1, 4, %g0
148 
149 	be	1f
150 	 andcc	%o1, 2, %g0
151 
152 	EX(st	%g3, [%o0], and %o1, 7)
153 	add	%o0, 4, %o0
154 1:
155 	be	1f
156 	 andcc	%o1, 1, %g0
157 
158 	EX(sth	%g3, [%o0], and %o1, 3)
159 	add	%o0, 2, %o0
160 1:
161 	bne,a	8f
162 	 EX(stb	%g3, [%o0], and %o1, 1)
163 8:
164 	b	0f
165 	 nop
166 7:
167 	be	13b
168 	 orcc	%o1, 0, %g0
169 
170 	be	0f
171 8:
172 	 add	%o0, 1, %o0
173 	subcc	%o1, 1, %o1
174 	bne	8b
175 	 EX(stb	%g3, [%o0 - 1], add %o1, 1)
176 0:
177 	andcc	%g4, 1, %g0
178 	be	5f
179 	 nop
180 	retl
181 	 mov	%g1, %o0
182 5:
183 	retl
184 	 clr	%o0
185 __memset_end:
186 
187 	.section .fixup,#alloc,#execinstr
188 	.align	4
189 20:
190 	cmp	%g2, 8
191 	bleu	1f
192 	 and	%o1, 0x7f, %o1
193 	sub	%g2, 9, %g2
194 	add	%o3, 64, %o3
195 1:
196 	sll	%g2, 3, %g2
197 	add	%o3, %o1, %o0
198 	b 30f
199 	 sub	%o0, %g2, %o0
200 21:
201 	mov	8, %o0
202 	and	%o1, 7, %o1
203 	sub	%o0, %g2, %o0
204 	sll	%o0, 3, %o0
205 	b 30f
206 	 add	%o0, %o1, %o0
207 30:
208 /* %o4 is faulting address, %o5 is %pc where fault occurred */
209 	save	%sp, -104, %sp
210 	mov	%i5, %o0
211 	mov	%i7, %o1
212 	call	lookup_fault
213 	 mov	%i4, %o2
214 	ret
215 	 restore
216 
217 	.globl __bzero_end
218 __bzero_end:
219