implement channels 1 and 2 of the legacy PIT.

ok otto, deraadt

diff --git a/usr.sbin/vmd/i8253.c b/usr.sbin/vmd/i8253.c
index de4045e..bddd86c 100644 (file)
--- a/usr.sbin/vmd/i8253.c
+++ b/usr.sbin/vmd/i8253.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: i8253.c,v 1.12 2017/03/27 00:28:04 deraadt Exp $ */
+/* $OpenBSD: i8253.c,v 1.13 2017/04/08 19:06:04 mlarkin Exp $ */
 /*
  * Copyright (c) 2016 Mike Larkin <mlarkin@openbsd.org>
  *
@@ -55,8 +55,21 @@ i8253_init(uint32_t vm_id)
        i8253_counter[0].start = 0xFFFF;
        i8253_counter[0].mode = TIMER_INTTC;
        i8253_counter[0].last_r = 1;
-       evtimer_set(&i8253_counter[0].timer, i8253_fire,
-           (void *)(intptr_t)vm_id);
+       i8253_counter[0].vm_id = vm_id;
+
+       i8253_counter[1].start = 0xFFFF;
+       i8253_counter[1].mode = TIMER_INTTC;
+       i8253_counter[1].last_r = 1;
+       i8253_counter[1].vm_id = vm_id;
+
+       i8253_counter[2].start = 0xFFFF;
+       i8253_counter[2].mode = TIMER_INTTC;
+       i8253_counter[2].last_r = 1;
+       i8253_counter[2].vm_id = vm_id;
+
+       evtimer_set(&i8253_counter[0].timer, i8253_fire, &i8253_counter[0]);
+       evtimer_set(&i8253_counter[1].timer, i8253_fire, &i8253_counter[1]);
+       evtimer_set(&i8253_counter[2].timer, i8253_fire, &i8253_counter[2]);
 }
 
 /*
@@ -74,13 +87,12 @@ i8253_do_readback(uint32_t data)
        struct timeval now, delta;
        uint64_t ns, ticks;
 
-       if ((data & TIMER_RB_C1) || (data & TIMER_RB_C2))
-               log_warnx("%s: readback of unsupported channel(s) "
-                   "requested", __func__);
-
        /* bits are inverted here - !TIMER_RB_STATUS == enable chan readback */
-       if (data & ~TIMER_RB_STATUS)
+       if (data & ~TIMER_RB_STATUS) {
                i8253_counter[0].rbs = (data & TIMER_RB_C0) ? 1 : 0;
+               i8253_counter[1].rbs = (data & TIMER_RB_C1) ? 1 : 0;
+               i8253_counter[2].rbs = (data & TIMER_RB_C2) ? 1 : 0;
+       }
 
        /* !TIMER_RB_COUNT == enable counter readback */
        if (data & ~TIMER_RB_COUNT) {
@@ -106,6 +118,52 @@ i8253_do_readback(uint32_t data)
                        else
                                i8253_counter[0].olatch = 0;
                }
+
+               if (data & TIMER_RB_C1) {
+                       gettimeofday(&now, NULL);
+                       delta.tv_sec = now.tv_sec - i8253_counter[1].tv.tv_sec;
+                       delta.tv_usec = now.tv_usec -
+                           i8253_counter[1].tv.tv_usec;
+                       if (delta.tv_usec < 0) {
+                               delta.tv_sec--;
+                               delta.tv_usec += 1000000;
+                       }
+                       if (delta.tv_usec > 1000000) {
+                               delta.tv_sec++;
+                               delta.tv_usec -= 1000000;
+                       }
+                       ns = delta.tv_usec * 1000 + delta.tv_sec * 1000000000;
+                       ticks = ns / NS_PER_TICK;
+                       if (i8253_counter[1].start)
+                               i8253_counter[1].olatch =
+                                   i8253_counter[1].start -
+                                   ticks % i8253_counter[1].start;
+                       else
+                               i8253_counter[1].olatch = 0;
+               }
+
+               if (data & TIMER_RB_C2) {
+                       gettimeofday(&now, NULL);
+                       delta.tv_sec = now.tv_sec - i8253_counter[2].tv.tv_sec;
+                       delta.tv_usec = now.tv_usec -
+                           i8253_counter[2].tv.tv_usec;
+                       if (delta.tv_usec < 0) {
+                               delta.tv_sec--;
+                               delta.tv_usec += 1000000;
+                       }
+                       if (delta.tv_usec > 1000000) {
+                               delta.tv_sec++;
+                               delta.tv_usec -= 1000000;
+                       }
+                       ns = delta.tv_usec * 1000 + delta.tv_sec * 1000000000;
+                       ticks = ns / NS_PER_TICK;
+                       if (i8253_counter[2].start)
+                               i8253_counter[2].olatch =
+                                   i8253_counter[2].start -
+                                   ticks % i8253_counter[2].start;
+                       else
+                               i8253_counter[2].olatch = 0;
+               }
        }
 }
 
@@ -196,11 +254,6 @@ vcpu_exit_i8253(struct vm_run_params *vrp)
        } else {
                sel = vei->vei.vei_port - (TIMER_CNTR0 + TIMER_BASE);
 
-               if (sel != 0) {
-                       log_warnx("%s: i8253 PIT: nonzero channel %d "
-                           "selected", __func__, sel);
-               }
-
                if (vei->vei.vei_dir == VEI_DIR_OUT) { /* OUT instruction */
                        if (i8253_counter[sel].last_w == 0) {
                                i8253_counter[sel].ilatch |= (out_data & 0xff);
@@ -212,6 +265,11 @@ vcpu_exit_i8253(struct vm_run_params *vrp)
                                i8253_counter[sel].last_w = 0;
                                mode = (out_data & 0xe) >> 1;
 
+                               if (i8253_counter[sel].start == 0)
+                                       i8253_counter[sel].start = 0xffff;
+                               
+                               log_debug("%s: channel %d reset, mode=%d, start=%d", __func__,
+                                   sel, mode, i8253_counter[sel].start);
                                i8253_counter[sel].mode = mode;
                                i8253_reset(sel);
                        }
@@ -253,18 +311,6 @@ i8253_reset(uint8_t chn)
 {
        struct timeval tv;
 
-       if (chn != 0) {
-               /*
-                * Channels other than 0 are not likely to be programmed
-                * by the guest. Long ago, channel 1 was used to refresh
-                * RAM, and channel 2 is sometimes routed to the PC
-                * speaker.
-                */
-               log_debug("%s: unsupported channel %d start request",
-                   __func__, chn);
-               return;
-       }
-
        evtimer_del(&i8253_counter[chn].timer);
        timerclear(&tv);
 
@@ -287,12 +333,13 @@ void
 i8253_fire(int fd, short type, void *arg)
 {
        struct timeval tv;
+       struct i8253_counter *ctr = (struct i8253_counter *)arg;
 
        timerclear(&tv);
-       tv.tv_usec = (i8253_counter[0].start * NS_PER_TICK) / 1000;
+       tv.tv_usec = (ctr->start * NS_PER_TICK) / 1000;
 
-       vcpu_assert_pic_irq((ptrdiff_t)arg, 0, 0);
+       vcpu_assert_pic_irq(ctr->vm_id, 0, 0);
 
-       if (i8253_counter[0].mode != TIMER_INTTC)
-               evtimer_add(&i8253_counter[0].timer, &tv);
+       if (ctr->mode != TIMER_INTTC)
+               evtimer_add(&ctr->timer, &tv);
 }

diff --git a/usr.sbin/vmd/i8253.h b/usr.sbin/vmd/i8253.h
index f0f94e5..0001668 100644 (file)
--- a/usr.sbin/vmd/i8253.h
+++ b/usr.sbin/vmd/i8253.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: i8253.h,v 1.3 2017/03/23 07:02:47 mlarkin Exp $ */
+/* $OpenBSD: i8253.h,v 1.4 2017/04/08 19:06:04 mlarkin Exp $ */
 /*
  * Copyright (c) 2016 Mike Larkin <mlarkin@openbsd.org>
  *
@@ -38,6 +38,7 @@ struct i8253_counter {
        uint8_t mode;           /* counter mode */
        uint8_t rbs;            /* channel is in readback status mode */
        struct event timer;     /* timer event for this counter */
+       uint32_t vm_id;         /* owning VM id */
 };
 
 void i8253_init(uint32_t);