.\" Copyright (c) 2006, 2008 Stanislav Sedov . .\" All rights reserved. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" .\" $FreeBSD$ .\" .Dd January 5, 2018 .Dt CPUCONTROL 8 .Os .Sh NAME .Nm cpucontrol .Nd control utility for the .Xr cpuctl 4 device .Sh SYNOPSIS .Nm .Bk .Op Fl v .Fl m Ar msr .Ar device .Ek .Bk .Nm .Op Fl v .Fl m Ar msr Ns = Ns Ar value .Ar device .Ek .Bk .Nm .Op Fl v .Fl m Ar msr Ns &= Ns Ar mask .Ar device .Ek .Bk .Nm .Op Fl v .Fl m Ar msr Ns |= Ns Ar mask .Ar device .Ek .Bk .Nm .Op Fl v .Fl i Ar level .Ar device .Ek .Bk .Nm .Op Fl v .Fl i Ar level,level_type .Ar device .Ek .Bk .Nm .Op Fl vn .Op Fl d Ar datadir .Fl u .Ar device .Ek .Bk .Nm .Fl e .Ar device .Ek .Sh DESCRIPTION The .Nm utility can be used to read and write arbitrary machine-specific CPU registers via the .Xr cpuctl 4 special device. It can also be used to apply CPU firmware updates. .Pp The following options are available: .Bl -tag -width indent .It Fl d Ar datadir Directory paths where to look for microcode images. The option can be specified multiple times. The paths are added in order of the options appearance on the command line, default directories are appended after the user-supplied paths. .It Fl n Do not look for the microcode images in the standard directories. Currently standard directory to look for the microcode update files is .Pa /usr/local/share/cpucontrol . .It Fl m Ar msr Show value of the specified MSR. MSR register number should be given as a hexadecimal number. The high word is printed first, then the low word is printed second. .It Fl m Ar msr Ns = Ns Ar value Store the .Ar value in the specified MSR register. The .Ar value argument can be prefixed with ~ operator. In this case the inverted value of argument will be stored in the register. .It Fl m Ar msr Ns &= Ns Ar mask Store the result of bitwise AND operation between .Ar mask and the current MSR value in the MSR register. The .Ar mask argument can be prefixed with ~ operator. In this case the inverted value of mask will be used. .It Fl m Ar msr Ns |= Ns Ar mask Store the result of bitwise OR operation between .Ar mask and the current MSR value in the MSR register. The .Ar mask argument can be prefixed with ~ operator. In this case the inverted value of mask will be used. .It Fl i Ar level Retrieve CPUID info. Level should be given as a hex number. .It Fl i Ar level,level_type Retrieve CPUID info. Level and level_type should be given as hex numbers. .It Fl u Apply CPU firmware updates. The .Nm utility will walk through the configured data directories and apply all firmware updates available for this CPU. .It Fl e Re-evaluate the kernel flags indicating the present CPU features. This command is typically executed after a firmware update was applied which changes information reported by the .Dv CPUID instruction. .Pp .Bf -symbolic Only execute the .Fl e command after the microcode update was applied to all CPUs in the system. The kernel does not operate correctly if the features of processors are not identical. .Ef .It Fl v Increase the verbosity level. .It Fl h Show help message. .El .Sh EXIT STATUS .Ex -std .Sh EXAMPLES The command .Pp .Dq Li "cpucontrol -m 0x10 /dev/cpuctl0" .Pp will read the contents of TSC MSR from CPU 0. .Pp To set the CPU 0 TSC MSR register value to 0x1 issue .Pp .Dq Li "cpucontrol -m 0x10=0x1 /dev/cpuctl0" . .Pp The following command will clear the second bit of TSC register: .Pp .Dq Li "cpucontrol -m 0x10&=~0x02 /dev/cpuctl0" . .Pp The following command will set the forth and second bit of TSC register: .Pp .Dq Li "cpucontrol -m 0x10|=0x0a /dev/cpuctl0" . .Pp The command .Pp .Dq Li "cpucontrol -i 0x1 /dev/cpuctl1" .Pp will retrieve the CPUID level 0x1 from CPU 1. .Pp To perform firmware updates on CPU 0 from images located at .Pa /usr/local/share/cpuctl use the following command: .Pp .Dq Li "cpucontrol -nd /usr/local/share/cpuctl -u /dev/cpuctl0" .Sh SEE ALSO .Xr cpuctl 4 .Sh HISTORY The .Nm utility first appeared in .Fx 7.2 . .Sh AUTHORS The .Nm utility and this manual page was written by .An Stanislav Sedov Aq Mt stas@FreeBSD.org .