source: mainline/kernel/arch/ppc32/src/interrupt.c@ 5f1fffb

/*
 * Copyright (c) 2006 Martin Decky
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - 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.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 THE AUTHOR 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.
 */

/** @addtogroup ppc32interrupt
 * @{
 */
/** @file
 */

#include <ddi/irq.h>
#include <interrupt.h>
#include <arch/interrupt.h>
#include <typedefs.h>
#include <arch.h>
#include <time/clock.h>
#include <ipc/sysipc.h>
#include <arch/drivers/pic.h>
#include <arch/mm/tlb.h>
#include <print.h>

void start_decrementer(void)
{
        asm volatile (
                "mtdec %[dec]\n"
                :: [dec] "r" (1000)
        );
}

/** External interrupts handler
 *
 */
static void exception_external(int n, istate_t *istate)
{
        uint8_t inum;
        
        while ((inum = pic_get_pending()) != 255) {
                irq_t *irq = irq_dispatch_and_lock(inum);
                if (irq) {
                        /*
                         * The IRQ handler was found.
                         */
                        
                        if (irq->preack) {
                                /* Acknowledge the interrupt before processing */
                                if (irq->cir)
                                        irq->cir(irq->cir_arg, irq->inr);
                        }
                        
                        irq->handler(irq);
                        
                        if (!irq->preack) {
                                if (irq->cir)
                                        irq->cir(irq->cir_arg, irq->inr);
                        }
                        
                        irq_spinlock_unlock(&irq->lock, false);
                } else {
                        /*
                         * Spurious interrupt.
                         */
#ifdef CONFIG_DEBUG
                        printf("cpu%" PRIs ": spurious interrupt (inum=%" PRIu8 ")\n",
                            CPU->id, inum);
#endif
                }
        }
}

static void exception_decrementer(int n, istate_t *istate)
{
        start_decrementer();
        clock();
}

/* Initialize basic tables for exception dispatching */
void interrupt_init(void)
{
        exc_register(VECTOR_DATA_STORAGE, "data_storage", true,
            pht_refill);
        exc_register(VECTOR_INSTRUCTION_STORAGE, "instruction_storage", true,
            pht_refill);
        exc_register(VECTOR_EXTERNAL, "external", true,
            exception_external);
        exc_register(VECTOR_DECREMENTER, "timer", true,
            exception_decrementer);
}

/** @}
 */