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authorbellard <bellard@c046a42c-6fe2-441c-8c8c-71466251a162>2004-03-14 12:20:30 +0000
committerbellard <bellard@c046a42c-6fe2-441c-8c8c-71466251a162>2004-03-14 12:20:30 +0000
commit80cabfad16384ca47f783a7c494bd1c3c6e3c4bc (patch)
treead2965750e60527e38280de84ab1d6d01d33ef68 /hw/i8259.c
parent38ca2abc2eb0fc8edd067420b3fcfa10ffa0054b (diff)
separated more devices from emulator
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@656 c046a42c-6fe2-441c-8c8c-71466251a162
Diffstat (limited to 'hw/i8259.c')
-rw-r--r--hw/i8259.c388
1 files changed, 388 insertions, 0 deletions
diff --git a/hw/i8259.c b/hw/i8259.c
new file mode 100644
index 0000000000..08c7be3943
--- /dev/null
+++ b/hw/i8259.c
@@ -0,0 +1,388 @@
+/*
+ * 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 <stdlib.h>
+#include <stdio.h>
+#include <stdarg.h>
+#include <string.h>
+#include <getopt.h>
+#include <inttypes.h>
+#include <unistd.h>
+#include <sys/mman.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <time.h>
+#include <sys/time.h>
+#include <malloc.h>
+#include <termios.h>
+#include <sys/poll.h>
+#include <errno.h>
+#include <sys/wait.h>
+#include <netinet/in.h>
+
+#include "cpu.h"
+#include "vl.h"
+
+/* debug PIC */
+//#define DEBUG_PIC
+
+typedef struct PicState {
+ uint8_t last_irr; /* edge detection */
+ uint8_t irr; /* interrupt request register */
+ uint8_t imr; /* interrupt mask register */
+ uint8_t isr; /* interrupt service register */
+ uint8_t priority_add; /* highest irq priority */
+ uint8_t irq_base;
+ uint8_t read_reg_select;
+ uint8_t poll;
+ uint8_t special_mask;
+ uint8_t init_state;
+ uint8_t auto_eoi;
+ uint8_t rotate_on_auto_eoi;
+ uint8_t special_fully_nested_mode;
+ uint8_t init4; /* true if 4 byte init */
+} PicState;
+
+/* 0 is master pic, 1 is slave pic */
+PicState pics[2];
+int pic_irq_requested;
+
+/* set irq level. If an edge is detected, then the IRR is set to 1 */
+static inline void pic_set_irq1(PicState *s, int irq, int level)
+{
+ int mask;
+ mask = 1 << irq;
+ if (level) {
+ if ((s->last_irr & mask) == 0)
+ s->irr |= mask;
+ s->last_irr |= mask;
+ } else {
+ s->last_irr &= ~mask;
+ }
+}
+
+/* return the highest priority found in mask (highest = smallest
+ number). Return 8 if no irq */
+static inline int get_priority(PicState *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(PicState *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_fully_nested_mode && s == &pics[0])
+ 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;
+ }
+}
+
+/* raise irq to CPU if necessary. must be called every time the active
+ irq may change */
+void pic_update_irq(void)
+{
+ int irq2, irq;
+
+ /* first look at slave pic */
+ irq2 = pic_get_irq(&pics[1]);
+ if (irq2 >= 0) {
+ /* if irq request by slave pic, signal master PIC */
+ pic_set_irq1(&pics[0], 2, 1);
+ pic_set_irq1(&pics[0], 2, 0);
+ }
+ /* look at requested irq */
+ irq = pic_get_irq(&pics[0]);
+ if (irq >= 0) {
+ if (irq == 2) {
+ /* from slave pic */
+ pic_irq_requested = 8 + irq2;
+ } else {
+ /* from master pic */
+ pic_irq_requested = irq;
+ }
+#if defined(DEBUG_PIC)
+ {
+ int i;
+ for(i = 0; i < 2; i++) {
+ printf("pic%d: imr=%x irr=%x padd=%d\n",
+ i, pics[i].imr, pics[i].irr, pics[i].priority_add);
+
+ }
+ }
+ printf("pic: cpu_interrupt req=%d\n", pic_irq_requested);
+#endif
+ cpu_interrupt(cpu_single_env, CPU_INTERRUPT_HARD);
+ }
+}
+
+#ifdef DEBUG_IRQ_LATENCY
+int64_t irq_time[16];
+int64_t cpu_get_ticks(void);
+#endif
+#if defined(DEBUG_PIC)
+int irq_level[16];
+#endif
+
+void pic_set_irq(int irq, int level)
+{
+#if defined(DEBUG_PIC)
+ if (level != irq_level[irq]) {
+ printf("pic_set_irq: irq=%d level=%d\n", irq, level);
+ irq_level[irq] = level;
+ }
+#endif
+#ifdef DEBUG_IRQ_LATENCY
+ if (level) {
+ irq_time[irq] = cpu_get_ticks();
+ }
+#endif
+ pic_set_irq1(&pics[irq >> 3], irq & 7, level);
+ pic_update_irq();
+}
+
+/* acknowledge interrupt 'irq' */
+static inline void pic_intack(PicState *s, int irq)
+{
+ if (s->auto_eoi) {
+ if (s->rotate_on_auto_eoi)
+ s->priority_add = (irq + 1) & 7;
+ } else {
+ s->isr |= (1 << irq);
+ }
+ s->irr &= ~(1 << irq);
+}
+
+int cpu_x86_get_pic_interrupt(CPUState *env)
+{
+ int irq, irq2, intno;
+
+ /* signal the pic that the irq was acked by the CPU */
+ irq = pic_irq_requested;
+#ifdef DEBUG_IRQ_LATENCY
+ printf("IRQ%d latency=%0.3fus\n",
+ irq,
+ (double)(cpu_get_ticks() - irq_time[irq]) * 1000000.0 / ticks_per_sec);
+#endif
+#if defined(DEBUG_PIC)
+ printf("pic_interrupt: irq=%d\n", irq);
+#endif
+
+ if (irq >= 8) {
+ irq2 = irq & 7;
+ pic_intack(&pics[1], irq2);
+ irq = 2;
+ intno = pics[1].irq_base + irq2;
+ } else {
+ intno = pics[0].irq_base + irq;
+ }
+ pic_intack(&pics[0], irq);
+ return intno;
+}
+
+void pic_ioport_write(CPUState *env, uint32_t addr, uint32_t val)
+{
+ PicState *s;
+ int priority, cmd, irq;
+
+#ifdef DEBUG_PIC
+ printf("pic_write: addr=0x%02x val=0x%02x\n", addr, val);
+#endif
+ s = &pics[addr >> 7];
+ addr &= 1;
+ if (addr == 0) {
+ if (val & 0x10) {
+ /* init */
+ memset(s, 0, sizeof(PicState));
+ s->init_state = 1;
+ s->init4 = val & 1;
+ if (val & 0x02)
+ hw_error("single mode not supported");
+ 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();
+ }
+ break;
+ case 3:
+ irq = val & 7;
+ s->isr &= ~(1 << irq);
+ pic_update_irq();
+ break;
+ case 6:
+ s->priority_add = (val + 1) & 7;
+ pic_update_irq();
+ break;
+ case 7:
+ irq = val & 7;
+ s->isr &= ~(1 << irq);
+ s->priority_add = (irq + 1) & 7;
+ pic_update_irq();
+ break;
+ default:
+ /* no operation */
+ break;
+ }
+ }
+ } else {
+ switch(s->init_state) {
+ case 0:
+ /* normal mode */
+ s->imr = val;
+ pic_update_irq();
+ break;
+ case 1:
+ s->irq_base = val & 0xf8;
+ s->init_state = 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 uint32_t pic_poll_read (PicState *s, uint32_t addr1)
+{
+ int ret;
+
+ ret = pic_get_irq(s);
+ if (ret >= 0) {
+ if (addr1 >> 7) {
+ pics[0].isr &= ~(1 << 2);
+ pics[0].irr &= ~(1 << 2);
+ }
+ s->irr &= ~(1 << ret);
+ s->isr &= ~(1 << ret);
+ if (addr1 >> 7 || ret != 2)
+ pic_update_irq();
+ } else {
+ ret = 0x07;
+ pic_update_irq();
+ }
+
+ return ret;
+}
+
+uint32_t pic_ioport_read(CPUState *env, uint32_t addr1)
+{
+ PicState *s;
+ unsigned int addr;
+ int ret;
+
+ addr = addr1;
+ s = &pics[addr >> 7];
+ addr &= 1;
+ if (s->poll) {
+ ret = pic_poll_read(s, addr1);
+ s->poll = 0;
+ } else {
+ if (addr == 0) {
+ if (s->read_reg_select)
+ ret = s->isr;
+ else
+ ret = s->irr;
+ } else {
+ ret = s->imr;
+ }
+ }
+#ifdef DEBUG_PIC
+ printf("pic_read: addr=0x%02x val=0x%02x\n", addr1, ret);
+#endif
+ return ret;
+}
+
+/* memory mapped interrupt status */
+uint32_t pic_intack_read(CPUState *env)
+{
+ int ret;
+
+ ret = pic_poll_read(&pics[0], 0x00);
+ if (ret == 2)
+ ret = pic_poll_read(&pics[1], 0x80) + 8;
+ /* Prepare for ISR read */
+ pics[0].read_reg_select = 1;
+
+ return ret;
+}
+
+void pic_init(void)
+{
+#if defined (TARGET_I386) || defined (TARGET_PPC)
+ register_ioport_write(0x20, 2, pic_ioport_write, 1);
+ register_ioport_read(0x20, 2, pic_ioport_read, 1);
+ register_ioport_write(0xa0, 2, pic_ioport_write, 1);
+ register_ioport_read(0xa0, 2, pic_ioport_read, 1);
+#endif
+}
+