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-rw-r--r--hw/intc/i8259.c498
1 files changed, 498 insertions, 0 deletions
diff --git a/hw/intc/i8259.c b/hw/intc/i8259.c
new file mode 100644
index 0000000000..fef00fca75
--- /dev/null
+++ b/hw/intc/i8259.c
@@ -0,0 +1,498 @@
+/*
+ * 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 = PIC_COMMON(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 = 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;
+
+ 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 = 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_init(PICCommonState *s)
+{
+ DeviceState *dev = DEVICE(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(dev, s->int_out, ARRAY_SIZE(s->int_out));
+ qdev_init_gpio_in(dev, 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 ? PIC_COMMON(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 = PIC_COMMON(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)
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