xref: /openbmc/linux/arch/mips/lib/memset.S (revision 588b48ca)
1/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License.  See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Copyright (C) 1998, 1999, 2000 by Ralf Baechle
7 * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
8 * Copyright (C) 2007 by Maciej W. Rozycki
9 * Copyright (C) 2011, 2012 MIPS Technologies, Inc.
10 */
11#include <asm/asm.h>
12#include <asm/asm-offsets.h>
13#include <asm/regdef.h>
14
15#if LONGSIZE == 4
16#define LONG_S_L swl
17#define LONG_S_R swr
18#else
19#define LONG_S_L sdl
20#define LONG_S_R sdr
21#endif
22
23#ifdef CONFIG_CPU_MICROMIPS
24#define STORSIZE (LONGSIZE * 2)
25#define STORMASK (STORSIZE - 1)
26#define FILL64RG t8
27#define FILLPTRG t7
28#undef  LONG_S
29#define LONG_S LONG_SP
30#else
31#define STORSIZE LONGSIZE
32#define STORMASK LONGMASK
33#define FILL64RG a1
34#define FILLPTRG t0
35#endif
36
37#define LEGACY_MODE 1
38#define EVA_MODE    2
39
40/*
41 * No need to protect it with EVA #ifdefery. The generated block of code
42 * will never be assembled if EVA is not enabled.
43 */
44#define __EVAFY(insn, reg, addr) __BUILD_EVA_INSN(insn##e, reg, addr)
45#define ___BUILD_EVA_INSN(insn, reg, addr) __EVAFY(insn, reg, addr)
46
47#define EX(insn,reg,addr,handler)			\
48	.if \mode == LEGACY_MODE;			\
499:		insn	reg, addr;			\
50	.else;						\
519:		___BUILD_EVA_INSN(insn, reg, addr);	\
52	.endif;						\
53	.section __ex_table,"a";			\
54	PTR	9b, handler;				\
55	.previous
56
57	.macro	f_fill64 dst, offset, val, fixup, mode
58	EX(LONG_S, \val, (\offset +  0 * STORSIZE)(\dst), \fixup)
59	EX(LONG_S, \val, (\offset +  1 * STORSIZE)(\dst), \fixup)
60	EX(LONG_S, \val, (\offset +  2 * STORSIZE)(\dst), \fixup)
61	EX(LONG_S, \val, (\offset +  3 * STORSIZE)(\dst), \fixup)
62#if ((defined(CONFIG_CPU_MICROMIPS) && (LONGSIZE == 4)) || !defined(CONFIG_CPU_MICROMIPS))
63	EX(LONG_S, \val, (\offset +  4 * STORSIZE)(\dst), \fixup)
64	EX(LONG_S, \val, (\offset +  5 * STORSIZE)(\dst), \fixup)
65	EX(LONG_S, \val, (\offset +  6 * STORSIZE)(\dst), \fixup)
66	EX(LONG_S, \val, (\offset +  7 * STORSIZE)(\dst), \fixup)
67#endif
68#if (!defined(CONFIG_CPU_MICROMIPS) && (LONGSIZE == 4))
69	EX(LONG_S, \val, (\offset +  8 * STORSIZE)(\dst), \fixup)
70	EX(LONG_S, \val, (\offset +  9 * STORSIZE)(\dst), \fixup)
71	EX(LONG_S, \val, (\offset + 10 * STORSIZE)(\dst), \fixup)
72	EX(LONG_S, \val, (\offset + 11 * STORSIZE)(\dst), \fixup)
73	EX(LONG_S, \val, (\offset + 12 * STORSIZE)(\dst), \fixup)
74	EX(LONG_S, \val, (\offset + 13 * STORSIZE)(\dst), \fixup)
75	EX(LONG_S, \val, (\offset + 14 * STORSIZE)(\dst), \fixup)
76	EX(LONG_S, \val, (\offset + 15 * STORSIZE)(\dst), \fixup)
77#endif
78	.endm
79
80	.set	noreorder
81	.align	5
82
83	/*
84	 * Macro to generate the __bzero{,_user} symbol
85	 * Arguments:
86	 * mode: LEGACY_MODE or EVA_MODE
87	 */
88	.macro __BUILD_BZERO mode
89	/* Initialize __memset if this is the first time we call this macro */
90	.ifnotdef __memset
91	.set __memset, 1
92	.hidden __memset /* Make sure it does not leak */
93	.endif
94
95	sltiu		t0, a2, STORSIZE	/* very small region? */
96	bnez		t0, .Lsmall_memset\@
97	andi		t0, a0, STORMASK	/* aligned? */
98
99#ifdef CONFIG_CPU_MICROMIPS
100	move		t8, a1			/* used by 'swp' instruction */
101	move		t9, a1
102#endif
103#ifndef CONFIG_CPU_DADDI_WORKAROUNDS
104	beqz		t0, 1f
105	PTR_SUBU	t0, STORSIZE		/* alignment in bytes */
106#else
107	.set		noat
108	li		AT, STORSIZE
109	beqz		t0, 1f
110	PTR_SUBU	t0, AT			/* alignment in bytes */
111	.set		at
112#endif
113
114	R10KCBARRIER(0(ra))
115#ifdef __MIPSEB__
116	EX(LONG_S_L, a1, (a0), .Lfirst_fixup\@)	/* make word/dword aligned */
117#endif
118#ifdef __MIPSEL__
119	EX(LONG_S_R, a1, (a0), .Lfirst_fixup\@)	/* make word/dword aligned */
120#endif
121	PTR_SUBU	a0, t0			/* long align ptr */
122	PTR_ADDU	a2, t0			/* correct size */
123
1241:	ori		t1, a2, 0x3f		/* # of full blocks */
125	xori		t1, 0x3f
126	beqz		t1, .Lmemset_partial\@	/* no block to fill */
127	andi		t0, a2, 0x40-STORSIZE
128
129	PTR_ADDU	t1, a0			/* end address */
130	.set		reorder
1311:	PTR_ADDIU	a0, 64
132	R10KCBARRIER(0(ra))
133	f_fill64 a0, -64, FILL64RG, .Lfwd_fixup\@, \mode
134	bne		t1, a0, 1b
135	.set		noreorder
136
137.Lmemset_partial\@:
138	R10KCBARRIER(0(ra))
139	PTR_LA		t1, 2f			/* where to start */
140#ifdef CONFIG_CPU_MICROMIPS
141	LONG_SRL	t7, t0, 1
142#endif
143#if LONGSIZE == 4
144	PTR_SUBU	t1, FILLPTRG
145#else
146	.set		noat
147	LONG_SRL	AT, FILLPTRG, 1
148	PTR_SUBU	t1, AT
149	.set		at
150#endif
151	jr		t1
152	PTR_ADDU	a0, t0			/* dest ptr */
153
154	.set		push
155	.set		noreorder
156	.set		nomacro
157	/* ... but first do longs ... */
158	f_fill64 a0, -64, FILL64RG, .Lpartial_fixup\@, \mode
1592:	.set		pop
160	andi		a2, STORMASK		/* At most one long to go */
161
162	beqz		a2, 1f
163	PTR_ADDU	a0, a2			/* What's left */
164	R10KCBARRIER(0(ra))
165#ifdef __MIPSEB__
166	EX(LONG_S_R, a1, -1(a0), .Llast_fixup\@)
167#endif
168#ifdef __MIPSEL__
169	EX(LONG_S_L, a1, -1(a0), .Llast_fixup\@)
170#endif
1711:	jr		ra
172	move		a2, zero
173
174.Lsmall_memset\@:
175	beqz		a2, 2f
176	PTR_ADDU	t1, a0, a2
177
1781:	PTR_ADDIU	a0, 1			/* fill bytewise */
179	R10KCBARRIER(0(ra))
180	bne		t1, a0, 1b
181	sb		a1, -1(a0)
182
1832:	jr		ra			/* done */
184	move		a2, zero
185	.if __memset == 1
186	END(memset)
187	.set __memset, 0
188	.hidden __memset
189	.endif
190
191.Lfirst_fixup\@:
192	jr	ra
193	nop
194
195.Lfwd_fixup\@:
196	PTR_L		t0, TI_TASK($28)
197	andi		a2, 0x3f
198	LONG_L		t0, THREAD_BUADDR(t0)
199	LONG_ADDU	a2, t1
200	jr		ra
201	LONG_SUBU	a2, t0
202
203.Lpartial_fixup\@:
204	PTR_L		t0, TI_TASK($28)
205	andi		a2, STORMASK
206	LONG_L		t0, THREAD_BUADDR(t0)
207	LONG_ADDU	a2, t1
208	jr		ra
209	LONG_SUBU	a2, t0
210
211.Llast_fixup\@:
212	jr		ra
213	andi		v1, a2, STORMASK
214
215	.endm
216
217/*
218 * memset(void *s, int c, size_t n)
219 *
220 * a0: start of area to clear
221 * a1: char to fill with
222 * a2: size of area to clear
223 */
224
225LEAF(memset)
226	beqz		a1, 1f
227	move		v0, a0			/* result */
228
229	andi		a1, 0xff		/* spread fillword */
230	LONG_SLL		t1, a1, 8
231	or		a1, t1
232	LONG_SLL		t1, a1, 16
233#if LONGSIZE == 8
234	or		a1, t1
235	LONG_SLL		t1, a1, 32
236#endif
237	or		a1, t1
2381:
239#ifndef CONFIG_EVA
240FEXPORT(__bzero)
241#endif
242	__BUILD_BZERO LEGACY_MODE
243
244#ifdef CONFIG_EVA
245LEAF(__bzero)
246	__BUILD_BZERO EVA_MODE
247END(__bzero)
248#endif
249