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diff --git a/share/man/man4/cpuctl.4 b/share/man/man4/cpuctl.4 new file mode 100644 index 0000000..3cc0138 --- /dev/null +++ b/share/man/man4/cpuctl.4 @@ -0,0 +1,193 @@ +.\" Copyright (c) 2006-2008 Stanislav Sedov <stas@FreeBSD.org> +.\" 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 June 20, 2014 +.Dt CPUCTL 4 +.Os +.Sh NAME +.Nm cpuctl +.Nd cpuctl pseudo device +.Sh SYNOPSIS +To compile this driver into the kernel, +place the following lines in your kernel +configuration file: +.Bd -ragged -offset indent +.Cd "device cpuctl" +.Ed +.Pp +Alternatively, to load the driver as a module +at boot time, place the following in +.Xr loader.conf 5 : +.Bd -literal -offset indent +cpuctl_load="YES" +.Ed +.Sh DESCRIPTION +The special device +.Pa /dev/cpuctl +presents interface to the system CPU. +It provides functionality to retrieve +CPUID information, read/write machine specific registers (MSR) and perform +CPU firmware updates. +.Pp +For each CPU present in the system, the special device +.Pa /dev/cpuctl%d +with the appropriate index will be created. +For multicore CPUs such a +special device will be created for each core. +.Pp +Currently, only i386 and amd64 processors are +supported. +.Sh IOCTL INTERFACE +All of the supported operations are invoked using the +.Xr ioctl 2 +system call. +Currently, the following ioctls are defined: +.Bl -tag -width CPUCTL_CPUID_COUNT +.It Dv CPUCTL_RDMSR Fa cpuctl_msr_args_t *args +.It Dv CPUCTL_WRMSR Fa cpuctl_msr_args_t *args +Read/write CPU machine specific register. +The +.Vt cpuctl_msr_args_t +structure is defined in +.In sys/cpuctl.h +as: +.Bd -literal +typedef struct { + int msr; /* MSR to read */ + uint64_t data; +} cpuctl_msr_args_t; +.Ed +.It Dv CPUCTL_MSRSBIT Fa cpuctl_msr_args_t *args +.It Dv CPUCTL_MSRCBIT Fa cpuctl_msr_args_t *args +Set/clear MSR bits according to the mask given in the +.Va data +field. +.It Dv CPUCTL_CPUID Fa cpuctl_cpuid_args_t *args +Retrieve CPUID information. +Arguments are supplied in the following structure: +.Bd -literal +typedef struct { + int level; /* CPUID level */ + uint32_t data[4]; +} cpuctl_cpuid_args_t; +.Ed +It is equivalent to the +.Dv CPUCTL_CPUID_COUNT +request with +.Va level_type +set to 0. +.It Dv CPUCTL_CPUID_COUNT Fa cpuctl_cpuid_count_args_t *args +Retrieve CPUID information. +Arguments are supplied in the following structure: +.Bd -literal +typedef struct { + int level; /* CPUID level */ + int level_type; /* CPUID level type */ + uint32_t data[4]; +} cpuctl_cpuid_count_args_t; +.Ed +The +.Va level +field indicates the CPUID level to retrieve, +it is loaded into the +.Va %eax +register before the CPUID instruction is executed, +The +.Va level_type +field indicates the CPUID level type to retrieve, +it is loaded into the +.Va %ecx +register. +.Pp +The +.Va data +field is used to store the received CPUID data. +That is, +.Va data[0] +contains the value of +.Va %eax +register after the CPUID instruction is executed, +.Va data[1] +is for +.Va %ebx , +.Va data[2] +for +.Va %ecx , +and +.Va data[3] +for +.Va %edx . +.It Dv CPUCTL_UPDATE cpuctl_update_args_t *args +Update CPU firmware (microcode). +The structure is defined in +.In sys/cpuctl.h +as: +.Bd -literal +typedef struct { + void *data; + size_t size; +} cpuctl_update_args_t; +.Ed +.Pp +The +.Va data +field should point to the firmware image of size +.Va size . +.El +.Pp +For additional information refer to +.Pa cpuctl.h . +.Sh RETURN VALUES +.Bl -tag -width Er +.It Bq Er ENXIO +The operation requested is not supported by the device (e.g., unsupported +architecture or the CPU is disabled). +.It Bq Er EINVAL +Incorrect request was supplied, or microcode image is not correct. +.It Bq Er ENOMEM +No physical memory was available to complete the request. +.It Bq Er EFAULT +The firmware image address points outside the process address space. +.El +.Sh FILES +.Bl -tag -width /dev/cpuctl -compact +.It Pa /dev/cpuctl +.El +.Sh SEE ALSO +.Xr hwpmc 4 , +.Xr cpucontrol 8 +.Sh HISTORY +The +.Nm +driver first appeared in +.Fx 7.2 . +.Sh AUTHORS +The +.Nm +module and this manual page were written by +.An Stanislav Sedov Aq stas@FreeBSD.org . +.Sh BUGS +Yes, probably, report if any. |
