xref: /openbmc/linux/arch/mips/lib/memset.S (revision 8684014d)
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#else
118	EX(LONG_S_R, a1, (a0), .Lfirst_fixup\@)	/* make word/dword aligned */
119#endif
120	PTR_SUBU	a0, t0			/* long align ptr */
121	PTR_ADDU	a2, t0			/* correct size */
122
1231:	ori		t1, a2, 0x3f		/* # of full blocks */
124	xori		t1, 0x3f
125	beqz		t1, .Lmemset_partial\@	/* no block to fill */
126	andi		t0, a2, 0x40-STORSIZE
127
128	PTR_ADDU	t1, a0			/* end address */
129	.set		reorder
1301:	PTR_ADDIU	a0, 64
131	R10KCBARRIER(0(ra))
132	f_fill64 a0, -64, FILL64RG, .Lfwd_fixup\@, \mode
133	bne		t1, a0, 1b
134	.set		noreorder
135
136.Lmemset_partial\@:
137	R10KCBARRIER(0(ra))
138	PTR_LA		t1, 2f			/* where to start */
139#ifdef CONFIG_CPU_MICROMIPS
140	LONG_SRL	t7, t0, 1
141#endif
142#if LONGSIZE == 4
143	PTR_SUBU	t1, FILLPTRG
144#else
145	.set		noat
146	LONG_SRL	AT, FILLPTRG, 1
147	PTR_SUBU	t1, AT
148	.set		at
149#endif
150	jr		t1
151	PTR_ADDU	a0, t0			/* dest ptr */
152
153	.set		push
154	.set		noreorder
155	.set		nomacro
156	/* ... but first do longs ... */
157	f_fill64 a0, -64, FILL64RG, .Lpartial_fixup\@, \mode
1582:	.set		pop
159	andi		a2, STORMASK		/* At most one long to go */
160
161	beqz		a2, 1f
162	PTR_ADDU	a0, a2			/* What's left */
163	R10KCBARRIER(0(ra))
164#ifdef __MIPSEB__
165	EX(LONG_S_R, a1, -1(a0), .Llast_fixup\@)
166#else
167	EX(LONG_S_L, a1, -1(a0), .Llast_fixup\@)
168#endif
1691:	jr		ra
170	move		a2, zero
171
172.Lsmall_memset\@:
173	beqz		a2, 2f
174	PTR_ADDU	t1, a0, a2
175
1761:	PTR_ADDIU	a0, 1			/* fill bytewise */
177	R10KCBARRIER(0(ra))
178	bne		t1, a0, 1b
179	sb		a1, -1(a0)
180
1812:	jr		ra			/* done */
182	move		a2, zero
183	.if __memset == 1
184	END(memset)
185	.set __memset, 0
186	.hidden __memset
187	.endif
188
189.Lfirst_fixup\@:
190	jr	ra
191	nop
192
193.Lfwd_fixup\@:
194	PTR_L		t0, TI_TASK($28)
195	andi		a2, 0x3f
196	LONG_L		t0, THREAD_BUADDR(t0)
197	LONG_ADDU	a2, t1
198	jr		ra
199	LONG_SUBU	a2, t0
200
201.Lpartial_fixup\@:
202	PTR_L		t0, TI_TASK($28)
203	andi		a2, STORMASK
204	LONG_L		t0, THREAD_BUADDR(t0)
205	LONG_ADDU	a2, t1
206	jr		ra
207	LONG_SUBU	a2, t0
208
209.Llast_fixup\@:
210	jr		ra
211	andi		v1, a2, STORMASK
212
213	.endm
214
215/*
216 * memset(void *s, int c, size_t n)
217 *
218 * a0: start of area to clear
219 * a1: char to fill with
220 * a2: size of area to clear
221 */
222
223LEAF(memset)
224	beqz		a1, 1f
225	move		v0, a0			/* result */
226
227	andi		a1, 0xff		/* spread fillword */
228	LONG_SLL		t1, a1, 8
229	or		a1, t1
230	LONG_SLL		t1, a1, 16
231#if LONGSIZE == 8
232	or		a1, t1
233	LONG_SLL		t1, a1, 32
234#endif
235	or		a1, t1
2361:
237#ifndef CONFIG_EVA
238FEXPORT(__bzero)
239#endif
240	__BUILD_BZERO LEGACY_MODE
241
242#ifdef CONFIG_EVA
243LEAF(__bzero)
244	__BUILD_BZERO EVA_MODE
245END(__bzero)
246#endif
247