Rev 3343 | Details | Compare with Previous | Last modification | View Log | RSS feed
| Rev | Author | Line No. | Line |
|---|---|---|---|
| 435 | jermar | 1 | /* |
| 2071 | jermar | 2 | * Copyright (c) 2005 Jakub Jermar |
| 435 | jermar | 3 | * All rights reserved. |
| 4 | * |
||
| 5 | * Redistribution and use in source and binary forms, with or without |
||
| 6 | * modification, are permitted provided that the following conditions |
||
| 7 | * are met: |
||
| 8 | * |
||
| 9 | * - Redistributions of source code must retain the above copyright |
||
| 10 | * notice, this list of conditions and the following disclaimer. |
||
| 11 | * - Redistributions in binary form must reproduce the above copyright |
||
| 12 | * notice, this list of conditions and the following disclaimer in the |
||
| 13 | * documentation and/or other materials provided with the distribution. |
||
| 14 | * - The name of the author may not be used to endorse or promote products |
||
| 15 | * derived from this software without specific prior written permission. |
||
| 16 | * |
||
| 17 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
||
| 18 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||
| 19 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
||
| 20 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
||
| 21 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||
| 22 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
||
| 23 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
||
| 24 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
||
| 25 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
||
| 26 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||
| 27 | */ |
||
| 28 | |||
| 1881 | jermar | 29 | /** @addtogroup ia64 |
| 1702 | cejka | 30 | * @{ |
| 31 | */ |
||
| 32 | /** @file |
||
| 33 | */ |
||
| 34 | |||
| 435 | jermar | 35 | /** Interval Timer driver. */ |
| 36 | |||
| 37 | #include <arch/drivers/it.h> |
||
| 38 | #include <arch/interrupt.h> |
||
| 39 | #include <arch/register.h> |
||
| 40 | #include <arch/asm.h> |
||
| 41 | #include <arch/barrier.h> |
||
| 42 | #include <time/clock.h> |
||
| 1942 | jermar | 43 | #include <ddi/irq.h> |
| 44 | #include <ddi/device.h> |
||
| 1482 | vana | 45 | #include <arch.h> |
| 435 | jermar | 46 | |
| 1482 | vana | 47 | #define IT_SERVICE_CLOCKS 64 |
| 48 | |||
| 3593 | rimsky | 49 | #define FREQ_NUMERATOR_SHIFT 32 |
| 50 | #define FREQ_NUMERATOR_MASK 0xffffffff00000000LL |
||
| 51 | |||
| 52 | #define FREQ_DENOMINATOR_SHIFT 0 |
||
| 53 | #define FREQ_DENOMINATOR_MASK 0xffffffffLL |
||
| 54 | |||
| 55 | |||
| 56 | uint64_t it_delta; |
||
| 57 | |||
| 58 | |||
| 1942 | jermar | 59 | static irq_t it_irq; |
| 60 | |||
| 61 | static irq_ownership_t it_claim(void); |
||
| 62 | static void it_interrupt(irq_t *irq, void *arg, ...); |
||
| 63 | |||
| 435 | jermar | 64 | /** Initialize Interval Timer. */ |
| 65 | void it_init(void) |
||
| 66 | { |
||
| 67 | cr_itv_t itv; |
||
| 3593 | rimsky | 68 | |
| 69 | if(config.cpu_active==1) |
||
| 70 | { |
||
| 71 | irq_initialize(&it_irq); |
||
| 72 | it_irq.inr = INTERRUPT_TIMER; |
||
| 73 | it_irq.devno = device_assign_devno(); |
||
| 74 | it_irq.claim = it_claim; |
||
| 75 | it_irq.handler = it_interrupt; |
||
| 76 | irq_register(&it_irq); |
||
| 77 | |||
| 78 | uint64_t base_freq; |
||
| 79 | base_freq = ((bootinfo->freq_scale) & FREQ_NUMERATOR_MASK) >> FREQ_NUMERATOR_SHIFT; |
||
| 80 | base_freq *= bootinfo->sys_freq; |
||
| 81 | base_freq /= ((bootinfo->freq_scale) & FREQ_DENOMINATOR_MASK) >> FREQ_DENOMINATOR_SHIFT; |
||
| 82 | |||
| 83 | it_delta = base_freq /HZ; |
||
| 84 | |||
| 85 | } |
||
| 86 | |||
| 435 | jermar | 87 | /* initialize Interval Timer external interrupt vector */ |
| 88 | itv.value = itv_read(); |
||
| 89 | itv.vector = INTERRUPT_TIMER; |
||
| 90 | itv.m = 0; |
||
| 91 | itv_write(itv.value); |
||
| 92 | |||
| 93 | /* set Interval Timer Counter to zero */ |
||
| 94 | itc_write(0); |
||
| 95 | |||
| 96 | /* generate first Interval Timer interrupt in IT_DELTA ticks */ |
||
| 97 | itm_write(IT_DELTA); |
||
| 456 | jermar | 98 | |
| 99 | /* propagate changes */ |
||
| 435 | jermar | 100 | srlz_d(); |
| 101 | } |
||
| 102 | |||
| 1942 | jermar | 103 | /** Always claim ownership for this IRQ. |
| 104 | * |
||
| 105 | * Other devices are responsible to avoid using INR 0. |
||
| 106 | * |
||
| 107 | * @return Always IRQ_ACCEPT. |
||
| 108 | */ |
||
| 109 | irq_ownership_t it_claim(void) |
||
| 110 | { |
||
| 111 | return IRQ_ACCEPT; |
||
| 112 | } |
||
| 1482 | vana | 113 | |
| 435 | jermar | 114 | /** Process Interval Timer interrupt. */ |
| 1942 | jermar | 115 | void it_interrupt(irq_t *irq, void *arg, ...) |
| 435 | jermar | 116 | { |
| 1780 | jermar | 117 | int64_t c; |
| 118 | int64_t m; |
||
| 1482 | vana | 119 | |
| 435 | jermar | 120 | eoi_write(EOI); |
| 1482 | vana | 121 | |
| 1881 | jermar | 122 | m = itm_read(); |
| 1482 | vana | 123 | |
| 1881 | jermar | 124 | while (1) { |
| 125 | c = itc_read(); |
||
| 126 | c += IT_SERVICE_CLOCKS; |
||
| 1482 | vana | 127 | |
| 1881 | jermar | 128 | m += IT_DELTA; |
| 1942 | jermar | 129 | if (m - c < 0) |
| 1482 | vana | 130 | CPU->missed_clock_ticks++; |
| 1881 | jermar | 131 | else |
| 132 | break; |
||
| 1482 | vana | 133 | } |
| 134 | |||
| 135 | itm_write(m); |
||
| 456 | jermar | 136 | srlz_d(); /* propagate changes */ |
| 2107 | jermar | 137 | |
| 138 | /* |
||
| 139 | * We are holding a lock which prevents preemption. |
||
| 140 | * Release the lock, call clock() and reacquire the lock again. |
||
| 141 | */ |
||
| 142 | spinlock_unlock(&irq->lock); |
||
| 435 | jermar | 143 | clock(); |
| 2107 | jermar | 144 | spinlock_lock(&irq->lock); |
| 435 | jermar | 145 | } |
| 1702 | cejka | 146 | |
| 1881 | jermar | 147 | /** @} |
| 1702 | cejka | 148 | */ |