| 0,0 → 1,155 |
|---|
| /* |
| * Copyright (c) 2003-2004 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 mips32interrupt |
| * @{ |
| */ |
| /** @file |
| */ |
| |
| #include <interrupt.h> |
| #include <arch/interrupt.h> |
| #include <arch/types.h> |
| #include <arch.h> |
| #include <arch/cp0.h> |
| #include <time/clock.h> |
| #include <arch/drivers/arc.h> |
| #include <ipc/sysipc.h> |
| #include <ddi/device.h> |
| |
| #define IRQ_COUNT 8 |
| #define TIMER_IRQ 7 |
| |
| function virtual_timer_fnc = NULL; |
| static irq_t timer_irq; |
| |
| /** Disable interrupts. |
| * |
| * @return Old interrupt priority level. |
| */ |
| ipl_t interrupts_disable(void) |
| { |
| ipl_t ipl = (ipl_t) cp0_status_read(); |
| cp0_status_write(ipl & ~cp0_status_ie_enabled_bit); |
| return ipl; |
| } |
| |
| /** Enable interrupts. |
| * |
| * @return Old interrupt priority level. |
| */ |
| ipl_t interrupts_enable(void) |
| { |
| ipl_t ipl = (ipl_t) cp0_status_read(); |
| cp0_status_write(ipl | cp0_status_ie_enabled_bit); |
| return ipl; |
| } |
| |
| /** Restore interrupt priority level. |
| * |
| * @param ipl Saved interrupt priority level. |
| */ |
| void interrupts_restore(ipl_t ipl) |
| { |
| cp0_status_write(cp0_status_read() | (ipl & cp0_status_ie_enabled_bit)); |
| } |
| |
| /** Read interrupt priority level. |
| * |
| * @return Current interrupt priority level. |
| */ |
| ipl_t interrupts_read(void) |
| { |
| return cp0_status_read(); |
| } |
| |
| /* TODO: This is SMP unsafe!!! */ |
| uint32_t count_hi = 0; |
| static unsigned long nextcount; |
| static unsigned long lastcount; |
| |
| /** Start hardware clock */ |
| static void timer_start(void) |
| { |
| lastcount = cp0_count_read(); |
| nextcount = cp0_compare_value + cp0_count_read(); |
| cp0_compare_write(nextcount); |
| } |
| |
| static irq_ownership_t timer_claim(void) |
| { |
| return IRQ_ACCEPT; |
| } |
| |
| static void timer_irq_handler(irq_t *irq, void *arg, ...) |
| { |
| unsigned long drift; |
| |
| if (cp0_count_read() < lastcount) |
| /* Count overflow detected */ |
| count_hi++; |
| lastcount = cp0_count_read(); |
| |
| drift = cp0_count_read() - nextcount; |
| while (drift > cp0_compare_value) { |
| drift -= cp0_compare_value; |
| CPU->missed_clock_ticks++; |
| } |
| nextcount = cp0_count_read() + cp0_compare_value - drift; |
| cp0_compare_write(nextcount); |
| |
| /* |
| * 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); |
| |
| if (virtual_timer_fnc != NULL) |
| virtual_timer_fnc(); |
| } |
| |
| /* Initialize basic tables for exception dispatching */ |
| void interrupt_init(void) |
| { |
| irq_init(IRQ_COUNT, IRQ_COUNT); |
| |
| irq_initialize(&timer_irq); |
| timer_irq.devno = device_assign_devno(); |
| timer_irq.inr = TIMER_IRQ; |
| timer_irq.claim = timer_claim; |
| timer_irq.handler = timer_irq_handler; |
| irq_register(&timer_irq); |
| |
| timer_start(); |
| cp0_unmask_int(TIMER_IRQ); |
| } |
| |
| /** @} |
| */ |