xref: /netbsd-src/sys/arch/arm/arm/cpufunc_asm_arm10.S (revision f81322cf185a4db50f71fcf7701f20198272620e)
1/*	$NetBSD: cpufunc_asm_arm10.S,v 1.5 2005/12/11 12:16:41 christos Exp $	*/
2
3/*
4 * Copyright (c) 2002 ARM Limited
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. The name of the company may not be used to endorse or promote
16 *    products derived from this software without specific prior written
17 *    permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
20 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
21 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22 * IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
23 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
24 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
25 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 * ARM10 assembly functions for CPU / MMU / TLB specific operations
32 */
33
34#include <machine/cpu.h>
35#include <machine/asm.h>
36
37/*
38 * Functions to set the MMU Translation Table Base register
39 *
40 * We need to clean and flush the cache as it uses virtual
41 * addresses that are about to change.
42 */
43ENTRY(arm10_setttb)
44	stmfd	sp!, {r0, lr}
45	bl	_C_LABEL(armv5_idcache_wbinv_all)
46	ldmfd	sp!, {r0, lr}
47
48	mcr	p15, 0, r0, c2, c0, 0	/* load new TTB */
49
50	mcr	p15, 0, r0, c8, c7, 0	/* invalidate I+D TLBs */
51	RET
52
53/*
54 * TLB functions
55 */
56ENTRY(arm10_tlb_flushID_SE)
57	mcr	p15, 0, r0, c8, c6, 1	/* flush D tlb single entry */
58	mcr	p15, 0, r0, c8, c5, 1	/* flush I tlb single entry */
59	RET
60
61ENTRY(arm10_tlb_flushI_SE)
62	mcr	p15, 0, r0, c8, c5, 1	/* flush I tlb single entry */
63	RET
64
65
66/*
67 * Context switch.
68 *
69 * These is the CPU-specific parts of the context switcher cpu_switch()
70 * These functions actually perform the TTB reload.
71 *
72 * NOTE: Special calling convention
73 *	r1, r4-r13 must be preserved
74 */
75ENTRY(arm10_context_switch)
76	/*
77	 * We can assume that the caches will only contain kernel addresses
78	 * at this point.  So no need to flush them again.
79	 */
80	mcr	p15, 0, r0, c7, c10, 4	/* drain the write buffer */
81	mcr	p15, 0, r0, c2, c0, 0	/* set the new TTB */
82	mcr	p15, 0, r0, c8, c7, 0	/* and flush the I+D tlbs */
83
84	/* Paranoia -- make sure the pipeline is empty. */
85	nop
86	nop
87	nop
88	RET
89