FreeBSD/Linux Kernel Cross Reference
sys/arm/arm/fiq.c
1 /* $NetBSD: fiq.c,v 1.5 2002/04/03 23:33:27 thorpej Exp $ */
2
3 /*-
4 * Copyright (c) 2001, 2002 Wasabi Systems, Inc.
5 * All rights reserved.
6 *
7 * Written by Jason R. Thorpe for Wasabi Systems, Inc.
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 for the NetBSD Project by
20 * Wasabi Systems, Inc.
21 * 4. The name of Wasabi Systems, Inc. may not be used to endorse
22 * or promote products derived from this software without specific prior
23 * written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC
29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35 * POSSIBILITY OF SUCH DAMAGE.
36 */
37
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD: src/sys/arm/arm/fiq.c,v 1.3 2005/03/16 07:56:21 jmg Exp $");
40
41 #include <sys/param.h>
42 #include <sys/systm.h>
43
44 #include <machine/cpufunc.h>
45 #include <machine/fiq.h>
46 #include <vm/vm.h>
47 #include <machine/pcb.h>
48 #include <vm/pmap.h>
49 #include <machine/cpu.h>
50
51 TAILQ_HEAD(, fiqhandler) fiqhandler_stack =
52 TAILQ_HEAD_INITIALIZER(fiqhandler_stack);
53
54 extern char fiqvector[];
55 extern char fiq_nullhandler[], fiq_nullhandler_end[];
56
57 #define IRQ_BIT I32_bit
58 #define FIQ_BIT F32_bit
59
60 /*
61 * fiq_installhandler:
62 *
63 * Actually install the FIQ handler down at the FIQ vector.
64 *
65 * Note: If the FIQ is invoked via an extra layer of
66 * indirection, the actual FIQ code store lives in the
67 * data segment, so there is no need to manipulate
68 * the vector page's protection.
69 */
70 static void
71 fiq_installhandler(void *func, size_t size)
72 {
73 #if !defined(__ARM_FIQ_INDIRECT)
74 vector_page_setprot(VM_PROT_READ|VM_PROT_WRITE);
75 #endif
76
77 memcpy(vector_page + fiqvector, func, size);
78
79 #if !defined(__ARM_FIQ_INDIRECT)
80 vector_page_setprot(VM_PROT_READ);
81 cpu_icache_sync_range((vm_offset_t) fiqvector, size);
82 #endif
83 }
84
85 /*
86 * fiq_claim:
87 *
88 * Claim the FIQ vector.
89 */
90 int
91 fiq_claim(struct fiqhandler *fh)
92 {
93 struct fiqhandler *ofh;
94 u_int oldirqstate;
95 int error = 0;
96
97 if (fh->fh_size > 0x100)
98 return (EFBIG);
99
100 oldirqstate = disable_interrupts(FIQ_BIT);
101
102 if ((ofh = TAILQ_FIRST(&fiqhandler_stack)) != NULL) {
103 if ((ofh->fh_flags & FH_CANPUSH) == 0) {
104 error = EBUSY;
105 goto out;
106 }
107
108 /* Save the previous FIQ handler's registers. */
109 if (ofh->fh_regs != NULL)
110 fiq_getregs(ofh->fh_regs);
111 }
112
113 /* Set FIQ mode registers to ours. */
114 if (fh->fh_regs != NULL)
115 fiq_setregs(fh->fh_regs);
116
117 TAILQ_INSERT_HEAD(&fiqhandler_stack, fh, fh_list);
118
119 /* Now copy the actual handler into place. */
120 fiq_installhandler(fh->fh_func, fh->fh_size);
121
122 /* Make sure FIQs are enabled when we return. */
123 oldirqstate &= ~FIQ_BIT;
124
125 out:
126 restore_interrupts(oldirqstate);
127 return (error);
128 }
129
130 /*
131 * fiq_release:
132 *
133 * Release the FIQ vector.
134 */
135 void
136 fiq_release(struct fiqhandler *fh)
137 {
138 u_int oldirqstate;
139 struct fiqhandler *ofh;
140
141 oldirqstate = disable_interrupts(FIQ_BIT);
142
143 /*
144 * If we are the currently active FIQ handler, then we
145 * need to save our registers and pop the next one back
146 * into the vector.
147 */
148 if (fh == TAILQ_FIRST(&fiqhandler_stack)) {
149 if (fh->fh_regs != NULL)
150 fiq_getregs(fh->fh_regs);
151 TAILQ_REMOVE(&fiqhandler_stack, fh, fh_list);
152 if ((ofh = TAILQ_FIRST(&fiqhandler_stack)) != NULL) {
153 if (ofh->fh_regs != NULL)
154 fiq_setregs(ofh->fh_regs);
155 fiq_installhandler(ofh->fh_func, ofh->fh_size);
156 }
157 } else
158 TAILQ_REMOVE(&fiqhandler_stack, fh, fh_list);
159
160 if (TAILQ_FIRST(&fiqhandler_stack) == NULL) {
161 /* Copy the NULL handler back down into the vector. */
162 fiq_installhandler(fiq_nullhandler,
163 (size_t)(fiq_nullhandler_end - fiq_nullhandler));
164
165 /* Make sure FIQs are disabled when we return. */
166 oldirqstate |= FIQ_BIT;
167 }
168
169 restore_interrupts(oldirqstate);
170 }
171 Cache object: afeee9bd48a7b7e5b94638f0b3e1800d
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