xref: /openbsd/sys/arch/arm/arm/cpufunc_asm.S (revision fdf77656)
1/*	$OpenBSD: cpufunc_asm.S,v 1.7 2019/11/07 21:54:49 patrick Exp $	*/
2/*	$NetBSD: cpufunc_asm.S,v 1.12 2003/09/06 09:14:52 rearnsha Exp $	*/
3
4/*
5 * Copyright (c) 1997,1998 Mark Brinicombe.
6 * Copyright (c) 1997 Causality Limited
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 3. All advertising materials mentioning features or use of this software
18 *    must display the following acknowledgement:
19 *	This product includes software developed by Causality Limited.
20 * 4. The name of Causality Limited may not be used to endorse or promote
21 *    products derived from this software without specific prior written
22 *    permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY CAUSALITY LIMITED ``AS IS'' AND ANY EXPRESS
25 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
26 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
27 * DISCLAIMED. IN NO EVENT SHALL CAUSALITY LIMITED BE LIABLE FOR ANY DIRECT,
28 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
29 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
30 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 *
36 * RiscBSD kernel project
37 *
38 * cpufunc.S
39 *
40 * Assembly functions for CPU / MMU / TLB specific operations
41 *
42 * Created      : 30/01/97
43 */
44
45#include <machine/asm.h>
46#include <arm/sysreg.h>
47
48	.text
49	.align	2
50
51ENTRY(cpufunc_nullop)
52	mov	pc, lr
53
54/*
55 * Generic functions to read the internal coprocessor registers
56 *
57 * Currently these registers are :
58 *  c0 - CPU ID
59 *  c5 - Fault status
60 *  c6 - Fault address
61 *
62 */
63
64ENTRY(cpufunc_id)
65	mrc	CP15_MIDR(r0)
66	mov	pc, lr
67
68ENTRY(cpu_get_control)
69	mrc	CP15_SCTLR(r0)
70	mov	pc, lr
71
72ENTRY(cpu_read_cache_config)
73	mrc	CP15_CTR(r0)
74	mov	pc, lr
75
76ENTRY(cpufunc_dfsr)
77	mrc	CP15_DFSR(r0)
78	mov	pc, lr
79
80ENTRY(cpufunc_dfar)
81	mrc	CP15_DFAR(r0)
82	mov	pc, lr
83
84ENTRY(cpufunc_ifsr)
85	mrc	CP15_IFSR(r0)
86	mov	pc, lr
87
88ENTRY(cpufunc_ifar)
89	mrc	CP15_IFAR(r0)
90	mov	pc, lr
91
92
93/*
94 * Generic functions to write the internal coprocessor registers
95 *
96 *
97 * Currently these registers are
98 *  c1 - CPU Control
99 *  c3 - Domain Access Control
100 *
101 * All other registers are CPU architecture specific
102 */
103
104#if 0 /* See below. */
105ENTRY(cpufunc_control)
106	mcr	CP15_SCTLR(r0)
107	mov	pc, lr
108#endif
109
110ENTRY(cpufunc_domains)
111	mcr	CP15_DACR(r0)
112	mov	pc, lr
113
114/*
115 * Generic functions to read/modify/write the internal coprocessor registers
116 *
117 *
118 * Currently these registers are
119 *  c1 - CPU Control
120 *
121 * All other registers are CPU architecture specific
122 */
123
124ENTRY(cpufunc_control)
125	mrc	CP15_SCTLR(r3)		/* Read the control register */
126	bic	r2, r3, r0		/* Clear bits */
127	eor	r2, r2, r1		/* XOR bits */
128
129	teq	r2, r3			/* Only write if there is a change */
130	mcrne	CP15_SCTLR(r2)		/* Write new control register */
131	mov	r0, r3			/* Return old value */
132	mov	pc, lr
133
134ENTRY(cpufunc_auxcontrol)
135	mrc	CP15_ACTLR(r3)		/* Read the aux control register */
136	bic	r2, r3, r0		/* Clear bits */
137	eor	r2, r2, r1		/* XOR bits */
138
139	teq	r2, r3			/* Only write if there is a change */
140	mcrne	CP15_ACTLR(r2)		/* Write new aux control register */
141	mov	r0, r3			/* Return old value */
142	mov	pc, lr
143