diff options
Diffstat (limited to 'sys/arm/arm/fiq.c')
| -rw-r--r-- | sys/arm/arm/fiq.c | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/sys/arm/arm/fiq.c b/sys/arm/arm/fiq.c new file mode 100644 index 000000000000..e55aa1276deb --- /dev/null +++ b/sys/arm/arm/fiq.c @@ -0,0 +1,172 @@ +/* $NetBSD: fiq.c,v 1.5 2002/04/03 23:33:27 thorpej Exp $ */ + +/*- + * Copyright (c) 2001, 2002 Wasabi Systems, Inc. + * All rights reserved. + * + * Written by Jason R. Thorpe for Wasabi Systems, Inc. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed for the NetBSD Project by + * Wasabi Systems, Inc. + * 4. The name of Wasabi Systems, Inc. may not be used to endorse + * or promote products derived from this software without specific prior + * written permission. + * + * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED + * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR + * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC + * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <sys/param.h> +#include <sys/systm.h> + +#include <machine/armreg.h> +#include <machine/cpufunc.h> +#include <machine/fiq.h> +#include <vm/vm.h> +#include <machine/pcb.h> +#include <vm/pmap.h> +#include <machine/cpu.h> + +TAILQ_HEAD(, fiqhandler) fiqhandler_stack = + TAILQ_HEAD_INITIALIZER(fiqhandler_stack); + +extern char *fiq_nullhandler_code; +extern uint32_t fiq_nullhandler_size; + +/* + * fiq_installhandler: + * + * Actually install the FIQ handler down at the FIQ vector. + * + * The FIQ vector is fixed by the hardware definition as the + * seventh 32-bit word in the vector page. + * + * Note: If the FIQ is invoked via an extra layer of + * indirection, the actual FIQ code store lives in the + * data segment, so there is no need to manipulate + * the vector page's protection. + */ +static void +fiq_installhandler(void *func, size_t size) +{ + const uint32_t fiqvector = 7 * sizeof(uint32_t); + +#if __ARM_ARCH < 6 && !defined(__ARM_FIQ_INDIRECT) + vector_page_setprot(VM_PROT_READ|VM_PROT_WRITE); +#endif + + memcpy((void *)(vector_page + fiqvector), func, size); + +#if __ARM_ARCH < 6 && !defined(__ARM_FIQ_INDIRECT) + vector_page_setprot(VM_PROT_READ); +#endif + icache_sync((vm_offset_t) fiqvector, size); +} + +/* + * fiq_claim: + * + * Claim the FIQ vector. + */ +int +fiq_claim(struct fiqhandler *fh) +{ + struct fiqhandler *ofh; + u_int oldirqstate; + int error = 0; + + if (fh->fh_size > 0x100) + return (EFBIG); + + oldirqstate = disable_interrupts(PSR_F); + + if ((ofh = TAILQ_FIRST(&fiqhandler_stack)) != NULL) { + if ((ofh->fh_flags & FH_CANPUSH) == 0) { + error = EBUSY; + goto out; + } + + /* Save the previous FIQ handler's registers. */ + if (ofh->fh_regs != NULL) + fiq_getregs(ofh->fh_regs); + } + + /* Set FIQ mode registers to ours. */ + if (fh->fh_regs != NULL) + fiq_setregs(fh->fh_regs); + + TAILQ_INSERT_HEAD(&fiqhandler_stack, fh, fh_list); + + /* Now copy the actual handler into place. */ + fiq_installhandler(fh->fh_func, fh->fh_size); + + /* Make sure FIQs are enabled when we return. */ + oldirqstate &= ~PSR_F; + + out: + restore_interrupts(oldirqstate); + return (error); +} + +/* + * fiq_release: + * + * Release the FIQ vector. + */ +void +fiq_release(struct fiqhandler *fh) +{ + u_int oldirqstate; + struct fiqhandler *ofh; + + oldirqstate = disable_interrupts(PSR_F); + + /* + * If we are the currently active FIQ handler, then we + * need to save our registers and pop the next one back + * into the vector. + */ + if (fh == TAILQ_FIRST(&fiqhandler_stack)) { + if (fh->fh_regs != NULL) + fiq_getregs(fh->fh_regs); + TAILQ_REMOVE(&fiqhandler_stack, fh, fh_list); + if ((ofh = TAILQ_FIRST(&fiqhandler_stack)) != NULL) { + if (ofh->fh_regs != NULL) + fiq_setregs(ofh->fh_regs); + fiq_installhandler(ofh->fh_func, ofh->fh_size); + } + } else + TAILQ_REMOVE(&fiqhandler_stack, fh, fh_list); + + if (TAILQ_FIRST(&fiqhandler_stack) == NULL) { + /* Copy the NULL handler back down into the vector. */ + fiq_installhandler(fiq_nullhandler_code, fiq_nullhandler_size); + + /* Make sure FIQs are disabled when we return. */ + oldirqstate |= PSR_F; + } + + restore_interrupts(oldirqstate); +} |