diff --git a/util/msrtool/freebsd.c b/util/msrtool/freebsd.c
new file mode 100644
index 0000000..912e1c9
--- /dev/null
+++ b/util/msrtool/freebsd.c
@@ -0,0 +1,105 @@
+/*
+ * This file is part of msrtool.
+ *
+ * Copyright (c) 2009 Andriy Gapon <avg@icyb.net.ua>
+ * Copyright (c) 2009 Peter Stuge <peter@stuge.se>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
+ */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <string.h>
+#include <errno.h>
+
+#include "msrtool.h"
+
+static int msr_fd[MAX_CORES] = {-1, -1, -1, -1, -1, -1, -1, -1};
+
+int freebsd_probe(const struct sysdef *system)
+{
+#ifdef __FreeBSD__
+	struct stat st;
+
+	return stat("/dev/cpuctl0", &st) == 0;
+#else
+	return 0;
+#endif
+}
+
+int freebsd_open(uint8_t cpu, enum SysModes mode)
+{
+#ifdef __FreeBSD__
+	int flags;
+	char devname[32];
+
+	if (cpu >= MAX_CORES)
+		return 0;
+
+	if (SYS_RDWR == mode)
+		flags = O_RDWR;
+	else if (SYS_WRONLY == mode)
+		flags = O_WRONLY;
+	else
+		flags = O_RDONLY;
+
+	snprintf(devname, sizeof(devname), "/dev/cpuctl%u", cpu);
+	msr_fd[cpu] = open(devname, flags);
+	if (msr_fd[cpu] < 0) {
+		perror(devname);
+		return 0;
+	}
+	return 1;
+#else
+	return 0;
+#endif
+}
+
+int freebsd_close(uint8_t cpu)
+{
+	if (cpu >= MAX_CORES)
+		return 0;
+
+	if (msr_fd[cpu] != -1)
+		close(msr_fd[cpu]);
+	msr_fd[cpu] = -1;
+	return 1;
+}
+
+int freebsd_rdmsr(uint8_t cpu, uint32_t addr, struct msr *val)
+{
+#ifdef __FreeBSD__
+	cpuctl_msr_args_t args;
+
+	if (cpu >= MAX_CORES)
+		return 0;
+
+	if (msr_fd[cpu] < 0)
+		return 0;
+
+	args.msr = addr;
+	if (ioctl(msr_fd[cpu], CPUCTL_RDMSR, &args) < 0) {
+		perror("ioctl(CPUCTL_RDMSR)");
+		return 0;
+	}
+
+	val->hi = args.data >> 32;
+	val->lo = args.data & 0xffffffff;
+	return 1;
+#else
+	return 0;
+#endif
+}