diff options
Diffstat (limited to 'hw/intc/i8259.c')
| -rw-r--r-- | hw/intc/i8259.c | 496 |
1 files changed, 496 insertions, 0 deletions
diff --git a/hw/intc/i8259.c b/hw/intc/i8259.c new file mode 100644 index 0000000000..ce14bd0f94 --- /dev/null +++ b/hw/intc/i8259.c @@ -0,0 +1,496 @@ +/* + * QEMU 8259 interrupt controller emulation + * + * Copyright (c) 2003-2004 Fabrice Bellard + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ +#include "hw/hw.h" +#include "hw/i386/pc.h" +#include "hw/isa/isa.h" +#include "monitor/monitor.h" +#include "qemu/timer.h" +#include "hw/isa/i8259_internal.h" + +/* debug PIC */ +//#define DEBUG_PIC + +#ifdef DEBUG_PIC +#define DPRINTF(fmt, ...) \ + do { printf("pic: " fmt , ## __VA_ARGS__); } while (0) +#else +#define DPRINTF(fmt, ...) +#endif + +//#define DEBUG_IRQ_LATENCY +//#define DEBUG_IRQ_COUNT + +#if defined(DEBUG_PIC) || defined(DEBUG_IRQ_COUNT) +static int irq_level[16]; +#endif +#ifdef DEBUG_IRQ_COUNT +static uint64_t irq_count[16]; +#endif +#ifdef DEBUG_IRQ_LATENCY +static int64_t irq_time[16]; +#endif +DeviceState *isa_pic; +static PICCommonState *slave_pic; + +/* return the highest priority found in mask (highest = smallest + number). Return 8 if no irq */ +static int get_priority(PICCommonState *s, int mask) +{ + int priority; + + if (mask == 0) { + return 8; + } + priority = 0; + while ((mask & (1 << ((priority + s->priority_add) & 7))) == 0) { + priority++; + } + return priority; +} + +/* return the pic wanted interrupt. return -1 if none */ +static int pic_get_irq(PICCommonState *s) +{ + int mask, cur_priority, priority; + + mask = s->irr & ~s->imr; + priority = get_priority(s, mask); + if (priority == 8) { + return -1; + } + /* compute current priority. If special fully nested mode on the + master, the IRQ coming from the slave is not taken into account + for the priority computation. */ + mask = s->isr; + if (s->special_mask) { + mask &= ~s->imr; + } + if (s->special_fully_nested_mode && s->master) { + mask &= ~(1 << 2); + } + cur_priority = get_priority(s, mask); + if (priority < cur_priority) { + /* higher priority found: an irq should be generated */ + return (priority + s->priority_add) & 7; + } else { + return -1; + } +} + +/* Update INT output. Must be called every time the output may have changed. */ +static void pic_update_irq(PICCommonState *s) +{ + int irq; + + irq = pic_get_irq(s); + if (irq >= 0) { + DPRINTF("pic%d: imr=%x irr=%x padd=%d\n", + s->master ? 0 : 1, s->imr, s->irr, s->priority_add); + qemu_irq_raise(s->int_out[0]); + } else { + qemu_irq_lower(s->int_out[0]); + } +} + +/* set irq level. If an edge is detected, then the IRR is set to 1 */ +static void pic_set_irq(void *opaque, int irq, int level) +{ + PICCommonState *s = opaque; + int mask = 1 << irq; + +#if defined(DEBUG_PIC) || defined(DEBUG_IRQ_COUNT) || \ + defined(DEBUG_IRQ_LATENCY) + int irq_index = s->master ? irq : irq + 8; +#endif +#if defined(DEBUG_PIC) || defined(DEBUG_IRQ_COUNT) + if (level != irq_level[irq_index]) { + DPRINTF("pic_set_irq: irq=%d level=%d\n", irq_index, level); + irq_level[irq_index] = level; +#ifdef DEBUG_IRQ_COUNT + if (level == 1) { + irq_count[irq_index]++; + } +#endif + } +#endif +#ifdef DEBUG_IRQ_LATENCY + if (level) { + irq_time[irq_index] = qemu_get_clock_ns(vm_clock); + } +#endif + + if (s->elcr & mask) { + /* level triggered */ + if (level) { + s->irr |= mask; + s->last_irr |= mask; + } else { + s->irr &= ~mask; + s->last_irr &= ~mask; + } + } else { + /* edge triggered */ + if (level) { + if ((s->last_irr & mask) == 0) { + s->irr |= mask; + } + s->last_irr |= mask; + } else { + s->last_irr &= ~mask; + } + } + pic_update_irq(s); +} + +/* acknowledge interrupt 'irq' */ +static void pic_intack(PICCommonState *s, int irq) +{ + if (s->auto_eoi) { + if (s->rotate_on_auto_eoi) { + s->priority_add = (irq + 1) & 7; + } + } else { + s->isr |= (1 << irq); + } + /* We don't clear a level sensitive interrupt here */ + if (!(s->elcr & (1 << irq))) { + s->irr &= ~(1 << irq); + } + pic_update_irq(s); +} + +int pic_read_irq(DeviceState *d) +{ + PICCommonState *s = DO_UPCAST(PICCommonState, dev.qdev, d); + int irq, irq2, intno; + + irq = pic_get_irq(s); + if (irq >= 0) { + if (irq == 2) { + irq2 = pic_get_irq(slave_pic); + if (irq2 >= 0) { + pic_intack(slave_pic, irq2); + } else { + /* spurious IRQ on slave controller */ + irq2 = 7; + } + intno = slave_pic->irq_base + irq2; + } else { + intno = s->irq_base + irq; + } + pic_intack(s, irq); + } else { + /* spurious IRQ on host controller */ + irq = 7; + intno = s->irq_base + irq; + } + +#if defined(DEBUG_PIC) || defined(DEBUG_IRQ_LATENCY) + if (irq == 2) { + irq = irq2 + 8; + } +#endif +#ifdef DEBUG_IRQ_LATENCY + printf("IRQ%d latency=%0.3fus\n", + irq, + (double)(qemu_get_clock_ns(vm_clock) - + irq_time[irq]) * 1000000.0 / get_ticks_per_sec()); +#endif + DPRINTF("pic_interrupt: irq=%d\n", irq); + return intno; +} + +static void pic_init_reset(PICCommonState *s) +{ + pic_reset_common(s); + pic_update_irq(s); +} + +static void pic_reset(DeviceState *dev) +{ + PICCommonState *s = DO_UPCAST(PICCommonState, dev.qdev, dev); + + s->elcr = 0; + pic_init_reset(s); +} + +static void pic_ioport_write(void *opaque, hwaddr addr64, + uint64_t val64, unsigned size) +{ + PICCommonState *s = opaque; + uint32_t addr = addr64; + uint32_t val = val64; + int priority, cmd, irq; + + DPRINTF("write: addr=0x%02x val=0x%02x\n", addr, val); + if (addr == 0) { + if (val & 0x10) { + pic_init_reset(s); + s->init_state = 1; + s->init4 = val & 1; + s->single_mode = val & 2; + if (val & 0x08) { + hw_error("level sensitive irq not supported"); + } + } else if (val & 0x08) { + if (val & 0x04) { + s->poll = 1; + } + if (val & 0x02) { + s->read_reg_select = val & 1; + } + if (val & 0x40) { + s->special_mask = (val >> 5) & 1; + } + } else { + cmd = val >> 5; + switch (cmd) { + case 0: + case 4: + s->rotate_on_auto_eoi = cmd >> 2; + break; + case 1: /* end of interrupt */ + case 5: + priority = get_priority(s, s->isr); + if (priority != 8) { + irq = (priority + s->priority_add) & 7; + s->isr &= ~(1 << irq); + if (cmd == 5) { + s->priority_add = (irq + 1) & 7; + } + pic_update_irq(s); + } + break; + case 3: + irq = val & 7; + s->isr &= ~(1 << irq); + pic_update_irq(s); + break; + case 6: + s->priority_add = (val + 1) & 7; + pic_update_irq(s); + break; + case 7: + irq = val & 7; + s->isr &= ~(1 << irq); + s->priority_add = (irq + 1) & 7; + pic_update_irq(s); + break; + default: + /* no operation */ + break; + } + } + } else { + switch (s->init_state) { + case 0: + /* normal mode */ + s->imr = val; + pic_update_irq(s); + break; + case 1: + s->irq_base = val & 0xf8; + s->init_state = s->single_mode ? (s->init4 ? 3 : 0) : 2; + break; + case 2: + if (s->init4) { + s->init_state = 3; + } else { + s->init_state = 0; + } + break; + case 3: + s->special_fully_nested_mode = (val >> 4) & 1; + s->auto_eoi = (val >> 1) & 1; + s->init_state = 0; + break; + } + } +} + +static uint64_t pic_ioport_read(void *opaque, hwaddr addr, + unsigned size) +{ + PICCommonState *s = opaque; + int ret; + + if (s->poll) { + ret = pic_get_irq(s); + if (ret >= 0) { + pic_intack(s, ret); + ret |= 0x80; + } else { + ret = 0; + } + s->poll = 0; + } else { + if (addr == 0) { + if (s->read_reg_select) { + ret = s->isr; + } else { + ret = s->irr; + } + } else { + ret = s->imr; + } + } + DPRINTF("read: addr=0x%02x val=0x%02x\n", addr, ret); + return ret; +} + +int pic_get_output(DeviceState *d) +{ + PICCommonState *s = DO_UPCAST(PICCommonState, dev.qdev, d); + + return (pic_get_irq(s) >= 0); +} + +static void elcr_ioport_write(void *opaque, hwaddr addr, + uint64_t val, unsigned size) +{ + PICCommonState *s = opaque; + s->elcr = val & s->elcr_mask; +} + +static uint64_t elcr_ioport_read(void *opaque, hwaddr addr, + unsigned size) +{ + PICCommonState *s = opaque; + return s->elcr; +} + +static const MemoryRegionOps pic_base_ioport_ops = { + .read = pic_ioport_read, + .write = pic_ioport_write, + .impl = { + .min_access_size = 1, + .max_access_size = 1, + }, +}; + +static const MemoryRegionOps pic_elcr_ioport_ops = { + .read = elcr_ioport_read, + .write = elcr_ioport_write, + .impl = { + .min_access_size = 1, + .max_access_size = 1, + }, +}; + +static void pic_init(PICCommonState *s) +{ + memory_region_init_io(&s->base_io, &pic_base_ioport_ops, s, "pic", 2); + memory_region_init_io(&s->elcr_io, &pic_elcr_ioport_ops, s, "elcr", 1); + + qdev_init_gpio_out(&s->dev.qdev, s->int_out, ARRAY_SIZE(s->int_out)); + qdev_init_gpio_in(&s->dev.qdev, pic_set_irq, 8); +} + +void pic_info(Monitor *mon, const QDict *qdict) +{ + int i; + PICCommonState *s; + + if (!isa_pic) { + return; + } + for (i = 0; i < 2; i++) { + s = i == 0 ? DO_UPCAST(PICCommonState, dev.qdev, isa_pic) : slave_pic; + monitor_printf(mon, "pic%d: irr=%02x imr=%02x isr=%02x hprio=%d " + "irq_base=%02x rr_sel=%d elcr=%02x fnm=%d\n", + i, s->irr, s->imr, s->isr, s->priority_add, + s->irq_base, s->read_reg_select, s->elcr, + s->special_fully_nested_mode); + } +} + +void irq_info(Monitor *mon, const QDict *qdict) +{ +#ifndef DEBUG_IRQ_COUNT + monitor_printf(mon, "irq statistic code not compiled.\n"); +#else + int i; + int64_t count; + + monitor_printf(mon, "IRQ statistics:\n"); + for (i = 0; i < 16; i++) { + count = irq_count[i]; + if (count > 0) { + monitor_printf(mon, "%2d: %" PRId64 "\n", i, count); + } + } +#endif +} + +qemu_irq *i8259_init(ISABus *bus, qemu_irq parent_irq) +{ + qemu_irq *irq_set; + ISADevice *dev; + int i; + + irq_set = g_malloc(ISA_NUM_IRQS * sizeof(qemu_irq)); + + dev = i8259_init_chip("isa-i8259", bus, true); + + qdev_connect_gpio_out(&dev->qdev, 0, parent_irq); + for (i = 0 ; i < 8; i++) { + irq_set[i] = qdev_get_gpio_in(&dev->qdev, i); + } + + isa_pic = &dev->qdev; + + dev = i8259_init_chip("isa-i8259", bus, false); + + qdev_connect_gpio_out(&dev->qdev, 0, irq_set[2]); + for (i = 0 ; i < 8; i++) { + irq_set[i + 8] = qdev_get_gpio_in(&dev->qdev, i); + } + + slave_pic = DO_UPCAST(PICCommonState, dev, dev); + + return irq_set; +} + +static void i8259_class_init(ObjectClass *klass, void *data) +{ + PICCommonClass *k = PIC_COMMON_CLASS(klass); + DeviceClass *dc = DEVICE_CLASS(klass); + + k->init = pic_init; + dc->reset = pic_reset; +} + +static const TypeInfo i8259_info = { + .name = "isa-i8259", + .instance_size = sizeof(PICCommonState), + .parent = TYPE_PIC_COMMON, + .class_init = i8259_class_init, +}; + +static void pic_register_types(void) +{ + type_register_static(&i8259_info); +} + +type_init(pic_register_types) |