CPUCTL(8)               NetBSD System Manager's Manual               CPUCTL(8)

     cpuctl -- program to control CPUs

     cpuctl [-v] command [arguments]

     The cpuctl command can be used to control and inspect the state of CPUs
     in the system.

     The first argument, command, specifies the action to take.  Valid com-
     mands are:

     identify cpu     Output information on the specified CPU's features and
                      capabilities.  Not available on all architectures.

     list             For each CPU in the system, display the current state
                      and time of the last state change.

     offline cpuno    Set the specified CPU off line.

                      Unbound LWPs (lightweight processes) will not be exe-
                      cuted on the CPU while it is off line.  Bound LWPs will
                      continue to be executed on the CPU, and device inter-
                      rupts routed to the CPU will continue to be handled.  A
                      future release of the system may allow device interrupts
                      to be re-routed away from individual CPUs.

                      At least one CPU in the system must remain on line.

     online cpuno     Set the specified CPU on line, making it available to
                      run unbound LWPs.

     ucode [cpuno] [file]
                      This applies the microcode patch to CPUs.  If cpuno is
                      not specified or -1, all CPUs are updated.  If cpuno is
                      -2, the current CPUs are updated.  The default filename
                      is used if no filename is specified.  The identify com-
                      mand prints the installed version on that CPU.  On suc-
                      cess the identify command show different ucode versions
                      before and after this command.

     Valid flags are:

     -v      Be more verbose.

     /dev/cpuctl  control device
                  The directory to install the microcode file for AMD CPUs
                  into.  The default filename is microcode_amd.bin for CPU
                  families 0x10 to 0x14.  The default filename is
                  microcode_amd_famXXh.bin where XX is the CPU family starting
                  with 15 (hex).  Get it from

           cpuctl identify 0
     and you should see something like this:

           cpu0: UCode version: 0x1000080

     After applying the microcode patch with
           cpuctl ucode
     you can see with
           cpuctl identify 0
     that the patch got applied:

           cpu0: UCode version: 0x1000083

     psrset(8), schedctl(8)

     The cpuctl command first appeared in NetBSD 5.0.

NetBSD 7.0                     November 20, 2014                    NetBSD 7.0

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