1 /* $NetBSD: fiq.c,v 1.5 2002/04/03 23:33:27 thorpej Exp $ */
4 * SPDX-License-Identifier: BSD-4-Clause
6 * Copyright (c) 2001, 2002 Wasabi Systems, Inc.
9 * Written by Jason R. Thorpe for Wasabi Systems, Inc.
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 * must display the following acknowledgement:
21 * This product includes software developed for the NetBSD Project by
22 * Wasabi Systems, Inc.
23 * 4. The name of Wasabi Systems, Inc. may not be used to endorse
24 * or promote products derived from this software without specific prior
27 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
29 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC
31 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37 * POSSIBILITY OF SUCH DAMAGE.
40 #include <sys/cdefs.h>
41 __FBSDID("$FreeBSD$");
43 #include <sys/param.h>
44 #include <sys/systm.h>
46 #include <machine/armreg.h>
47 #include <machine/cpufunc.h>
48 #include <machine/fiq.h>
50 #include <machine/pcb.h>
52 #include <machine/cpu.h>
54 TAILQ_HEAD(, fiqhandler) fiqhandler_stack =
55 TAILQ_HEAD_INITIALIZER(fiqhandler_stack);
57 extern char *fiq_nullhandler_code;
58 extern uint32_t fiq_nullhandler_size;
63 * Actually install the FIQ handler down at the FIQ vector.
65 * The FIQ vector is fixed by the hardware definition as the
66 * seventh 32-bit word in the vector page.
68 * Note: If the FIQ is invoked via an extra layer of
69 * indirection, the actual FIQ code store lives in the
70 * data segment, so there is no need to manipulate
71 * the vector page's protection.
74 fiq_installhandler(void *func, size_t size)
76 const uint32_t fiqvector = 7 * sizeof(uint32_t);
78 #if __ARM_ARCH < 6 && !defined(__ARM_FIQ_INDIRECT)
79 vector_page_setprot(VM_PROT_READ|VM_PROT_WRITE);
82 memcpy((void *)(vector_page + fiqvector), func, size);
84 #if __ARM_ARCH < 6 && !defined(__ARM_FIQ_INDIRECT)
85 vector_page_setprot(VM_PROT_READ);
87 icache_sync((vm_offset_t) fiqvector, size);
93 * Claim the FIQ vector.
96 fiq_claim(struct fiqhandler *fh)
98 struct fiqhandler *ofh;
102 if (fh->fh_size > 0x100)
105 oldirqstate = disable_interrupts(PSR_F);
107 if ((ofh = TAILQ_FIRST(&fiqhandler_stack)) != NULL) {
108 if ((ofh->fh_flags & FH_CANPUSH) == 0) {
113 /* Save the previous FIQ handler's registers. */
114 if (ofh->fh_regs != NULL)
115 fiq_getregs(ofh->fh_regs);
118 /* Set FIQ mode registers to ours. */
119 if (fh->fh_regs != NULL)
120 fiq_setregs(fh->fh_regs);
122 TAILQ_INSERT_HEAD(&fiqhandler_stack, fh, fh_list);
124 /* Now copy the actual handler into place. */
125 fiq_installhandler(fh->fh_func, fh->fh_size);
127 /* Make sure FIQs are enabled when we return. */
128 oldirqstate &= ~PSR_F;
131 restore_interrupts(oldirqstate);
138 * Release the FIQ vector.
141 fiq_release(struct fiqhandler *fh)
144 struct fiqhandler *ofh;
146 oldirqstate = disable_interrupts(PSR_F);
149 * If we are the currently active FIQ handler, then we
150 * need to save our registers and pop the next one back
153 if (fh == TAILQ_FIRST(&fiqhandler_stack)) {
154 if (fh->fh_regs != NULL)
155 fiq_getregs(fh->fh_regs);
156 TAILQ_REMOVE(&fiqhandler_stack, fh, fh_list);
157 if ((ofh = TAILQ_FIRST(&fiqhandler_stack)) != NULL) {
158 if (ofh->fh_regs != NULL)
159 fiq_setregs(ofh->fh_regs);
160 fiq_installhandler(ofh->fh_func, ofh->fh_size);
163 TAILQ_REMOVE(&fiqhandler_stack, fh, fh_list);
165 if (TAILQ_FIRST(&fiqhandler_stack) == NULL) {
166 /* Copy the NULL handler back down into the vector. */
167 fiq_installhandler(fiq_nullhandler_code, fiq_nullhandler_size);
169 /* Make sure FIQs are disabled when we return. */
170 oldirqstate |= PSR_F;
173 restore_interrupts(oldirqstate);