| 0,0 → 1,127 |
|---|
| /* |
| * Copyright (c) 2005 Jakub Jermar |
| * 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 ia64 |
| * @{ |
| */ |
| /** @file |
| */ |
| |
| /** Interval Timer driver. */ |
| |
| #include <arch/drivers/it.h> |
| #include <arch/interrupt.h> |
| #include <arch/register.h> |
| #include <arch/asm.h> |
| #include <arch/barrier.h> |
| #include <time/clock.h> |
| #include <ddi/irq.h> |
| #include <ddi/device.h> |
| #include <arch.h> |
| |
| #define IT_SERVICE_CLOCKS 64 |
| |
| static irq_t it_irq; |
| |
| static irq_ownership_t it_claim(void); |
| static void it_interrupt(irq_t *irq, void *arg, ...); |
| |
| /** Initialize Interval Timer. */ |
| void it_init(void) |
| { |
| cr_itv_t itv; |
| |
| irq_initialize(&it_irq); |
| it_irq.inr = INTERRUPT_TIMER; |
| it_irq.devno = device_assign_devno(); |
| it_irq.claim = it_claim; |
| it_irq.handler = it_interrupt; |
| irq_register(&it_irq); |
| |
| /* initialize Interval Timer external interrupt vector */ |
| itv.value = itv_read(); |
| itv.vector = INTERRUPT_TIMER; |
| itv.m = 0; |
| itv_write(itv.value); |
| |
| /* set Interval Timer Counter to zero */ |
| itc_write(0); |
| |
| /* generate first Interval Timer interrupt in IT_DELTA ticks */ |
| itm_write(IT_DELTA); |
| |
| /* propagate changes */ |
| srlz_d(); |
| } |
| |
| /** Always claim ownership for this IRQ. |
| * |
| * Other devices are responsible to avoid using INR 0. |
| * |
| * @return Always IRQ_ACCEPT. |
| */ |
| irq_ownership_t it_claim(void) |
| { |
| return IRQ_ACCEPT; |
| } |
| |
| /** Process Interval Timer interrupt. */ |
| void it_interrupt(irq_t *irq, void *arg, ...) |
| { |
| int64_t c; |
| int64_t m; |
| |
| eoi_write(EOI); |
| |
| m = itm_read(); |
| |
| while (1) { |
| c = itc_read(); |
| c += IT_SERVICE_CLOCKS; |
| |
| m += IT_DELTA; |
| if (m - c < 0) |
| CPU->missed_clock_ticks++; |
| else |
| break; |
| } |
| |
| itm_write(m); |
| srlz_d(); /* propagate changes */ |
| |
| /* |
| * We are holding a lock which prevents preemption. |
| * Release the lock, call clock() and reacquire the lock again. |
| */ |
| spinlock_unlock(&irq->lock); |
| clock(); |
| spinlock_lock(&irq->lock); |
| } |
| |
| /** @} |
| */ |