1 /* $NetBSD: fiq.c,v 1.5 2002/04/03 23:33:27 thorpej Exp $ */
4 * Copyright (c) 2001, 2002 Wasabi Systems, Inc.
7 * Written by Jason R. Thorpe for Wasabi Systems, Inc.
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
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
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.
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
41 #include <sys/param.h>
42 #include <sys/systm.h>
44 #include <machine/armreg.h>
45 #include <machine/cpufunc.h>
46 #include <machine/fiq.h>
48 #include <machine/pcb.h>
50 #include <machine/cpu.h>
52 TAILQ_HEAD(, fiqhandler) fiqhandler_stack =
53 TAILQ_HEAD_INITIALIZER(fiqhandler_stack);
55 extern char *fiq_nullhandler_code;
56 extern uint32_t fiq_nullhandler_size;
61 * Actually install the FIQ handler down at the FIQ vector.
63 * The FIQ vector is fixed by the hardware definition as the
64 * seventh 32-bit word in the vector page.
66 * Note: If the FIQ is invoked via an extra layer of
67 * indirection, the actual FIQ code store lives in the
68 * data segment, so there is no need to manipulate
69 * the vector page's protection.
72 fiq_installhandler(void *func, size_t size)
74 const uint32_t fiqvector = 7 * sizeof(uint32_t);
76 #if !defined(__ARM_FIQ_INDIRECT)
77 vector_page_setprot(VM_PROT_READ|VM_PROT_WRITE);
80 memcpy((void *)(vector_page + fiqvector), func, size);
82 #if !defined(__ARM_FIQ_INDIRECT)
83 vector_page_setprot(VM_PROT_READ);
84 cpu_icache_sync_range((vm_offset_t) fiqvector, size);
91 * Claim the FIQ vector.
94 fiq_claim(struct fiqhandler *fh)
96 struct fiqhandler *ofh;
100 if (fh->fh_size > 0x100)
103 oldirqstate = disable_interrupts(PSR_F);
105 if ((ofh = TAILQ_FIRST(&fiqhandler_stack)) != NULL) {
106 if ((ofh->fh_flags & FH_CANPUSH) == 0) {
111 /* Save the previous FIQ handler's registers. */
112 if (ofh->fh_regs != NULL)
113 fiq_getregs(ofh->fh_regs);
116 /* Set FIQ mode registers to ours. */
117 if (fh->fh_regs != NULL)
118 fiq_setregs(fh->fh_regs);
120 TAILQ_INSERT_HEAD(&fiqhandler_stack, fh, fh_list);
122 /* Now copy the actual handler into place. */
123 fiq_installhandler(fh->fh_func, fh->fh_size);
125 /* Make sure FIQs are enabled when we return. */
126 oldirqstate &= ~PSR_F;
129 restore_interrupts(oldirqstate);
136 * Release the FIQ vector.
139 fiq_release(struct fiqhandler *fh)
142 struct fiqhandler *ofh;
144 oldirqstate = disable_interrupts(PSR_F);
147 * If we are the currently active FIQ handler, then we
148 * need to save our registers and pop the next one back
151 if (fh == TAILQ_FIRST(&fiqhandler_stack)) {
152 if (fh->fh_regs != NULL)
153 fiq_getregs(fh->fh_regs);
154 TAILQ_REMOVE(&fiqhandler_stack, fh, fh_list);
155 if ((ofh = TAILQ_FIRST(&fiqhandler_stack)) != NULL) {
156 if (ofh->fh_regs != NULL)
157 fiq_setregs(ofh->fh_regs);
158 fiq_installhandler(ofh->fh_func, ofh->fh_size);
161 TAILQ_REMOVE(&fiqhandler_stack, fh, fh_list);
163 if (TAILQ_FIRST(&fiqhandler_stack) == NULL) {
164 /* Copy the NULL handler back down into the vector. */
165 fiq_installhandler(fiq_nullhandler_code, fiq_nullhandler_size);
167 /* Make sure FIQs are disabled when we return. */
168 oldirqstate |= PSR_F;
171 restore_interrupts(oldirqstate);