pmtmr.c revision 245652
1/*- 2 * Copyright (c) 2012 NetApp, Inc. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL NETAPP, INC OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD: head/usr.sbin/bhyve/pmtmr.c 245123 2013-01-07 04:51:43Z grehan $ 27 */ 28 29#include <sys/cdefs.h> 30__FBSDID("$FreeBSD: head/usr.sbin/bhyve/pmtmr.c 245123 2013-01-07 04:51:43Z grehan $"); 31 32#include <sys/types.h> 33#include <sys/sysctl.h> 34#include <sys/time.h> 35#include <machine/cpufunc.h> 36 37#include <stdio.h> 38#include <time.h> 39#include <assert.h> 40#include <pthread.h> 41 42#include "inout.h" 43 44/* 45 * The ACPI Power Management timer is a free-running 24- or 32-bit 46 * timer with a frequency of 3.579545MHz 47 * 48 * This implementation will be 32-bits 49 */ 50 51#define IO_PMTMR 0x408 /* 4-byte i/o port for the timer */ 52 53#define PMTMR_FREQ 3579545 /* 3.579545MHz */ 54 55static pthread_mutex_t pmtmr_mtx; 56static uint64_t pmtmr_tscf; 57static uint64_t pmtmr_old; 58static uint64_t pmtmr_tsc_old; 59 60static uint32_t 61pmtmr_val(void) 62{ 63 uint64_t pmtmr_tsc_new; 64 uint64_t pmtmr_new; 65 static int inited = 0; 66 67 if (!inited) { 68 size_t len; 69 uint32_t tmpf; 70 71 inited = 1; 72 pthread_mutex_init(&pmtmr_mtx, NULL); 73 len = sizeof(tmpf); 74 sysctlbyname("machdep.tsc_freq", &tmpf, &len, 75 NULL, 0); 76 pmtmr_tscf = tmpf; 77 pmtmr_tsc_old = rdtsc(); 78 pmtmr_old = pmtmr_tsc_old / pmtmr_tscf * PMTMR_FREQ; 79 return (pmtmr_old); 80 } 81 82 pthread_mutex_lock(&pmtmr_mtx); 83 pmtmr_tsc_new = rdtsc(); 84 pmtmr_new = (pmtmr_tsc_new - pmtmr_tsc_old) * PMTMR_FREQ / pmtmr_tscf + 85 pmtmr_old; 86 pmtmr_old = pmtmr_new; 87 pmtmr_tsc_old = pmtmr_tsc_new; 88 pthread_mutex_unlock(&pmtmr_mtx); 89 90 return (pmtmr_new); 91} 92 93static int 94pmtmr_handler(struct vmctx *ctx, int vcpu, int in, int port, int bytes, 95 uint32_t *eax, void *arg) 96{ 97 assert(in == 1); 98 99 if (bytes != 4) 100 return (-1); 101 102 *eax = pmtmr_val(); 103 104 return (0); 105} 106 107INOUT_PORT(pmtmr, IO_PMTMR, IOPORT_F_IN, pmtmr_handler); 108 109