diff options
| author |   mlarkin <mlarkin@openbsd.org> | 2018-04-27 08:57:13 +0000 |
|---|---|---|
| committer | mlarkin <mlarkin@openbsd.org> | 2018-04-27 08:57:13 +0000 |
| commit | 5272a52da352549adcc9346419e84db795e836ce (patch) | |
| tree | 82b3c6cdb246e83cb887db58b25839df597dfd27 | |
| parent | Fix the prologue detection to match amd64 opcodes, not i386 opcodes (diff) | |
| download | wireguard-openbsd-5272a52da352549adcc9346419e84db795e836ce.tar.xz wireguard-openbsd-5272a52da352549adcc9346419e84db795e836ce.zip | |
vmd(8): allow counter state readback via misc port for square wave mode
| -rw-r--r-- | usr.sbin/vmd/i8253.c | 37 |
1 files changed, 28 insertions, 9 deletions
diff --git a/usr.sbin/vmd/i8253.c b/usr.sbin/vmd/i8253.c index c218acce748..ef24a31277d 100644 --- a/usr.sbin/vmd/i8253.c +++ b/usr.sbin/vmd/i8253.c @@ -1,4 +1,4 @@ -/* $OpenBSD: i8253.c,v 1.23 2018/04/27 06:44:43 mlarkin Exp $ */ +/* $OpenBSD: i8253.c,v 1.24 2018/04/27 08:57:13 mlarkin Exp $ */ /* * Copyright (c) 2016 Mike Larkin <mlarkin@openbsd.org> * @@ -138,17 +138,36 @@ uint8_t vcpu_exit_i8253_misc(struct vm_run_params *vrp) { union vm_exit *vei = vrp->vrp_exit; + uint16_t cur; + uint64_t ns, ticks; + struct timespec now, delta; if (vei->vei.vei_dir == VEI_DIR_IN) { /* Port 0x61[5] = counter channel 2 state */ - if (i8253_channel[2].state) { - set_return_data(vei, (1 << 5)); - log_debug("%s: counter 2 fired, returning 0x20", - __func__); - } else { - set_return_data(vei, 0); - log_debug("%s: counter 2 clear, returning 0x0", - __func__); + if (i8253_channel[2].mode == TIMER_INTTC) { + if (i8253_channel[2].state) { + set_return_data(vei, (1 << 5)); + log_debug("%s: counter 2 fired, returning " + "0x20", __func__); + } else { + set_return_data(vei, 0); + log_debug("%s: counter 2 clear, returning 0x0", + __func__); + } + } else if (i8253_channel[2].mode == TIMER_SQWAVE) { + clock_gettime(CLOCK_MONOTONIC, &now); + timespecsub(&now, &i8253_channel[2].ts, &delta); + ns = delta.tv_sec * 1000000000 + delta.tv_nsec; + ticks = ns / NS_PER_TICK; + if (i8253_channel[2].start) { + cur = i8253_channel[2].start - + ticks % i8253_channel[2].start; + + if (cur > i8253_channel[2].start / 2) + set_return_data(vei, 1); + else + set_return_data(vei, 0); + } } } else { log_debug("%s: discarding data written to PIT misc port\n", |