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CPUCONTROL(8) FreeBSD System Manager's Manual CPUCONTROL(8) NAME cpucontrol -- control utility for the cpuctl(4) device. SYNOPSIS cpucontrol [-vh] -m msr device cpucontrol [-vh] -m msr=value device cpucontrol [-vh] -m msr&=mask device cpucontrol [-vh] -m msr|=mask device cpucontrol [-vh] -i level device cpucontrol [-vh] [-d datadir] -u device DESCRIPTION The cpucontrol utility can be used to read and write arbitrary machine- specific CPU registers via the cpuctl(4) special device. It can also be used to apply CPU firmware updates. The following options are available: -d datadir Where to look for microcode images. The option can be specified multiple times. -m msr[=value] Show value of the specified MSR. MSR register number should be given as a hexadecimal number. -m msr=value Store the value in the specified MSR register. The value argu- ment can be prefixed with ~ operator. In this case the inverted value of argument will be stored in the register. -m msr&=mask Store the result of bitwise AND operation between mask and the current MSR value in the MSR register. The mask argument can be prefixed with ~ operator. In this case the inverted value of mask will be used. -m msr|=mask Store the result of bitwise OR operation between mask and the current MSR value in the MSR register. The mask argument can be prefixed with ~ operator. In this case the inverted value of mask will be used. -i level Retrieve CPUID info. Level should be given as a hex number. -u Apply CPU firmware updates. The cpucontrol utility will walk through the configured data directories and apply all firmware updates available for this CPU. -v Increase the verbosity level. -h Show help message. EXIT STATUS The cpucontrol utility exits 0 on success, and >0 if an error occurs. EXAMPLES The command ``cpucontrol -m 0x10 /dev/cpuctl0'' will read the contents of TSC MSR from CPU 0. To set the CPU 0 TSC MSR register value to 0x1 issue ``cpucontrol -m 0x10=0x1 /dev/cpuctl0''. The following command will clear the second bit of TSC register: ``cpucontrol -m 0x10&=~0x02 /dev/cpuctl0''. The following command will set the forth and second bit of TSC register: ``cpucontrol -m 0x10|=0x0a /dev/cpuctl0''. The command ``cpucontrol -i 0x1 /dev/cpuctl1'' will retrieve the CPUID level 0x1 from CPU 1. To perform firmware updates on CPU 0 from images located at /usr/local/share/cpuctl/ use the following command: ``cpucontrol -d /usr/local/share/cpuctl/ -u /dev/cpuctl0'' SEE ALSO cpuctl(4) HISTORY The cpucontrol utility first appeared in FreeBSD 7.2. BUGS Yes, probably, report if any. AUTHORS The cpucontrol utility and this manual page was written by Stanislav Sedov <stas@FreeBSD.org>. FreeBSD 11.1 June 30, 2009 FreeBSD 11.1
NAME | SYNOPSIS | DESCRIPTION | EXIT STATUS | EXAMPLES | SEE ALSO | HISTORY | BUGS | AUTHORS
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