| /* |
| * 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 "qemu/osdep.h" |
| #include "hw/intc/i8259.h" |
| #include "hw/irq.h" |
| #include "hw/isa/isa.h" |
| #include "qemu/timer.h" |
| #include "qemu/log.h" |
| #include "hw/isa/i8259_internal.h" |
| #include "trace.h" |
| #include "qom/object.h" |
| |
| /* debug PIC */ |
| //#define DEBUG_PIC |
| |
| //#define DEBUG_IRQ_LATENCY |
| |
| #define TYPE_I8259 "isa-i8259" |
| typedef struct PICClass PICClass; |
| DECLARE_CLASS_CHECKERS(PICClass, PIC, |
| TYPE_I8259) |
| |
| /** |
| * PICClass: |
| * @parent_realize: The parent's realizefn. |
| */ |
| struct PICClass { |
| PICCommonClass parent_class; |
| |
| DeviceRealize parent_realize; |
| }; |
| |
| #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) { |
| trace_pic_update_irq(s->master, 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; |
| int irq_index = s->master ? irq : irq + 8; |
| |
| trace_pic_set_irq(s->master, irq, level); |
| pic_stat_update_irq(irq_index, level); |
| |
| #ifdef DEBUG_IRQ_LATENCY |
| if (level) { |
| irq_time[irq_index] = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); |
| } |
| #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 = PIC_COMMON(d); |
| int irq, intno; |
| |
| irq = pic_get_irq(s); |
| if (irq >= 0) { |
| int irq2; |
| |
| 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; |
| pic_intack(s, irq); |
| irq = irq2 + 8; |
| } else { |
| intno = s->irq_base + irq; |
| pic_intack(s, irq); |
| } |
| } else { |
| /* spurious IRQ on host controller */ |
| irq = 7; |
| intno = s->irq_base + irq; |
| } |
| |
| #ifdef DEBUG_IRQ_LATENCY |
| printf("IRQ%d latency=%0.3fus\n", |
| irq, |
| (double)(qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) - |
| irq_time[irq]) * 1000000.0 / NANOSECONDS_PER_SECOND); |
| #endif |
| |
| trace_pic_interrupt(irq, intno); |
| 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 = PIC_COMMON(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; |
| |
| trace_pic_ioport_write(s->master, 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) { |
| qemu_log_mask(LOG_UNIMP, |
| "i8259: level sensitive irq not supported\n"); |
| } |
| } 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; |
| } |
| } |
| trace_pic_ioport_read(s->master, addr, ret); |
| return ret; |
| } |
| |
| int pic_get_output(DeviceState *d) |
| { |
| PICCommonState *s = PIC_COMMON(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_realize(DeviceState *dev, Error **errp) |
| { |
| PICCommonState *s = PIC_COMMON(dev); |
| PICClass *pc = PIC_GET_CLASS(dev); |
| |
| memory_region_init_io(&s->base_io, OBJECT(s), &pic_base_ioport_ops, s, |
| "pic", 2); |
| memory_region_init_io(&s->elcr_io, OBJECT(s), &pic_elcr_ioport_ops, s, |
| "elcr", 1); |
| |
| qdev_init_gpio_out(dev, s->int_out, ARRAY_SIZE(s->int_out)); |
| qdev_init_gpio_in(dev, pic_set_irq, 8); |
| |
| pc->parent_realize(dev, errp); |
| } |
| |
| qemu_irq *i8259_init(ISABus *bus, qemu_irq parent_irq) |
| { |
| qemu_irq *irq_set; |
| DeviceState *dev; |
| ISADevice *isadev; |
| int i; |
| |
| irq_set = g_new0(qemu_irq, ISA_NUM_IRQS); |
| |
| isadev = i8259_init_chip(TYPE_I8259, bus, true); |
| dev = DEVICE(isadev); |
| |
| qdev_connect_gpio_out(dev, 0, parent_irq); |
| for (i = 0 ; i < 8; i++) { |
| irq_set[i] = qdev_get_gpio_in(dev, i); |
| } |
| |
| isa_pic = dev; |
| |
| isadev = i8259_init_chip(TYPE_I8259, bus, false); |
| dev = DEVICE(isadev); |
| |
| qdev_connect_gpio_out(dev, 0, irq_set[2]); |
| for (i = 0 ; i < 8; i++) { |
| irq_set[i + 8] = qdev_get_gpio_in(dev, i); |
| } |
| |
| slave_pic = PIC_COMMON(dev); |
| |
| return irq_set; |
| } |
| |
| static void i8259_class_init(ObjectClass *klass, void *data) |
| { |
| PICClass *k = PIC_CLASS(klass); |
| DeviceClass *dc = DEVICE_CLASS(klass); |
| |
| device_class_set_parent_realize(dc, pic_realize, &k->parent_realize); |
| dc->reset = pic_reset; |
| } |
| |
| static const TypeInfo i8259_info = { |
| .name = TYPE_I8259, |
| .instance_size = sizeof(PICCommonState), |
| .parent = TYPE_PIC_COMMON, |
| .class_init = i8259_class_init, |
| .class_size = sizeof(PICClass), |
| }; |
| |
| static void pic_register_types(void) |
| { |
| type_register_static(&i8259_info); |
| } |
| |
| type_init(pic_register_types) |