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/acle-compat.h>
45 #include <machine/armreg.h>
46 #include <machine/cpufunc.h>
47 #include <machine/fiq.h>
49 #include <machine/pcb.h>
51 #include <machine/cpu.h>
53 TAILQ_HEAD(, fiqhandler) fiqhandler_stack =
54 TAILQ_HEAD_INITIALIZER(fiqhandler_stack);
56 extern char *fiq_nullhandler_code;
57 extern uint32_t fiq_nullhandler_size;
62 * Actually install the FIQ handler down at the FIQ vector.
64 * The FIQ vector is fixed by the hardware definition as the
65 * seventh 32-bit word in the vector page.
67 * Note: If the FIQ is invoked via an extra layer of
68 * indirection, the actual FIQ code store lives in the
69 * data segment, so there is no need to manipulate
70 * the vector page's protection.
73 fiq_installhandler(void *func, size_t size)
75 const uint32_t fiqvector = 7 * sizeof(uint32_t);
77 #if __ARM_ARCH < 6 && !defined(__ARM_FIQ_INDIRECT)
78 vector_page_setprot(VM_PROT_READ|VM_PROT_WRITE);
81 memcpy((void *)(vector_page + fiqvector), func, size);
83 #if __ARM_ARCH < 6 && !defined(__ARM_FIQ_INDIRECT)
84 vector_page_setprot(VM_PROT_READ);
86 icache_sync((vm_offset_t) fiqvector, size);
92 * Claim the FIQ vector.
95 fiq_claim(struct fiqhandler *fh)
97 struct fiqhandler *ofh;
101 if (fh->fh_size > 0x100)
104 oldirqstate = disable_interrupts(PSR_F);
106 if ((ofh = TAILQ_FIRST(&fiqhandler_stack)) != NULL) {
107 if ((ofh->fh_flags & FH_CANPUSH) == 0) {
112 /* Save the previous FIQ handler's registers. */
113 if (ofh->fh_regs != NULL)
114 fiq_getregs(ofh->fh_regs);
117 /* Set FIQ mode registers to ours. */
118 if (fh->fh_regs != NULL)
119 fiq_setregs(fh->fh_regs);
121 TAILQ_INSERT_HEAD(&fiqhandler_stack, fh, fh_list);
123 /* Now copy the actual handler into place. */
124 fiq_installhandler(fh->fh_func, fh->fh_size);
126 /* Make sure FIQs are enabled when we return. */
127 oldirqstate &= ~PSR_F;
130 restore_interrupts(oldirqstate);
137 * Release the FIQ vector.
140 fiq_release(struct fiqhandler *fh)
143 struct fiqhandler *ofh;
145 oldirqstate = disable_interrupts(PSR_F);
148 * If we are the currently active FIQ handler, then we
149 * need to save our registers and pop the next one back
152 if (fh == TAILQ_FIRST(&fiqhandler_stack)) {
153 if (fh->fh_regs != NULL)
154 fiq_getregs(fh->fh_regs);
155 TAILQ_REMOVE(&fiqhandler_stack, fh, fh_list);
156 if ((ofh = TAILQ_FIRST(&fiqhandler_stack)) != NULL) {
157 if (ofh->fh_regs != NULL)
158 fiq_setregs(ofh->fh_regs);
159 fiq_installhandler(ofh->fh_func, ofh->fh_size);
162 TAILQ_REMOVE(&fiqhandler_stack, fh, fh_list);
164 if (TAILQ_FIRST(&fiqhandler_stack) == NULL) {
165 /* Copy the NULL handler back down into the vector. */
166 fiq_installhandler(fiq_nullhandler_code, fiq_nullhandler_size);
168 /* Make sure FIQs are disabled when we return. */
169 oldirqstate |= PSR_F;
172 restore_interrupts(oldirqstate);