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diff --git a/static/freebsd/man4/cpufreq.4 3.html b/static/freebsd/man4/cpufreq.4 3.html deleted file mode 100644 index c2b02a7d..00000000 --- a/static/freebsd/man4/cpufreq.4 3.html +++ /dev/null @@ -1,279 +0,0 @@ -<table class="head"> - <tr> - <td class="head-ltitle">CPUFREQ(4)</td> - <td class="head-vol">Device Drivers Manual</td> - <td class="head-rtitle">CPUFREQ(4)</td> - </tr> -</table> -<div class="manual-text"> -<section class="Sh"> -<h1 class="Sh" id="NAME"><a class="permalink" href="#NAME">NAME</a></h1> -<p class="Pp"><code class="Nm">cpufreq</code> — <span class="Nd">CPU - frequency control framework</span></p> -</section> -<section class="Sh"> -<h1 class="Sh" id="SYNOPSIS"><a class="permalink" href="#SYNOPSIS">SYNOPSIS</a></h1> -<p class="Pp"><code class="Cd">device cpufreq</code></p> -<p class="Pp"> - <br/> - <code class="In">#include <<a class="In">sys/cpu.h</a>></code></p> -<p class="Pp"><var class="Ft">int</var> - <br/> - <code class="Fn">cpufreq_levels</code>(<var class="Fa" style="white-space: nowrap;">device_t - dev</var>, <var class="Fa" style="white-space: nowrap;">struct cf_level - *levels</var>, <var class="Fa" style="white-space: nowrap;">int - *count</var>);</p> -<p class="Pp"><var class="Ft">int</var> - <br/> - <code class="Fn">cpufreq_set</code>(<var class="Fa" style="white-space: nowrap;">device_t - dev</var>, <var class="Fa" style="white-space: nowrap;">const struct - cf_level *level</var>, <var class="Fa" style="white-space: nowrap;">int - priority</var>);</p> -<p class="Pp"><var class="Ft">int</var> - <br/> - <code class="Fn">cpufreq_get</code>(<var class="Fa" style="white-space: nowrap;">device_t - dev</var>, <var class="Fa" style="white-space: nowrap;">struct cf_level - *level</var>);</p> -<p class="Pp"><var class="Ft">int</var> - <br/> - <code class="Fn">cpufreq_drv_settings</code>(<var class="Fa">device_t - dev</var>, <var class="Fa">struct cf_setting *sets</var>, - <var class="Fa">int *count</var>);</p> -<p class="Pp"><var class="Ft">int</var> - <br/> - <code class="Fn">cpufreq_drv_type</code>(<var class="Fa" style="white-space: nowrap;">device_t - dev</var>, <var class="Fa" style="white-space: nowrap;">int - *type</var>);</p> -<p class="Pp"><var class="Ft">int</var> - <br/> - <code class="Fn">cpufreq_drv_set</code>(<var class="Fa" style="white-space: nowrap;">device_t - dev</var>, <var class="Fa" style="white-space: nowrap;">const struct - cf_setting *set</var>);</p> -<p class="Pp"><var class="Ft">int</var> - <br/> - <code class="Fn">cpufreq_drv_get</code>(<var class="Fa" style="white-space: nowrap;">device_t - dev</var>, <var class="Fa" style="white-space: nowrap;">struct cf_setting - *set</var>);</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="DESCRIPTION"><a class="permalink" href="#DESCRIPTION">DESCRIPTION</a></h1> -<p class="Pp">The <code class="Nm">cpufreq</code> driver provides a unified - kernel and user interface to CPU frequency control drivers. It combines - multiple drivers offering different settings into a single interface of all - possible levels. Users can access this interface directly via - <a class="Xr">sysctl(8)</a> or by indicating to - <span class="Pa">/etc/rc.d/power_profile</span> that it should switch - settings when the AC line state changes via - <a class="Xr">rc.conf(5)</a>.</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="SYSCTL_VARIABLES"><a class="permalink" href="#SYSCTL_VARIABLES">SYSCTL - VARIABLES</a></h1> -<p class="Pp">These settings may be overridden by kernel drivers requesting - alternate settings. If this occurs, the original values will be restored - once the condition has passed (e.g., the system has cooled sufficiently). If - a sysctl cannot be set due to an override condition, it will return - <code class="Er">EPERM</code>.</p> -<p class="Pp">The frequency cannot be changed if TSC is in use as the - timecounter and the hardware does not support invariant TSC. This is because - the timecounter system needs to use a source that has a constant rate. (On - invariant TSC hardware, the TSC runs at the P0 rate regardless of the - configured P-state.) Modern hardware mostly has invariant TSC. The - timecounter source can be changed with the - <span class="Pa">kern.timecounter.hardware</span> sysctl. Available modes - are in <span class="Pa">kern.timecounter.choice</span> sysctl entry.</p> -<dl class="Bl-tag"> - <dt id="dev.cpu._d.freq"><var class="Va">dev.cpu.%d.freq</var></dt> - <dd>Current active CPU frequency in MHz.</dd> - <dt id="dev.cpu._d.freq_driver"><var class="Va">dev.cpu.%d.freq_driver</var></dt> - <dd>The specific <code class="Nm">cpufreq</code> driver used by this cpu.</dd> - <dt id="dev.cpu._d.freq_levels"><var class="Va">dev.cpu.%d.freq_levels</var></dt> - <dd>Currently available levels for the CPU (frequency/power usage). Values are - in units of MHz and milliwatts.</dd> - <dt id="dev.DEVICE._d.freq_settings"><var class="Va">dev.DEVICE.%d.freq_settings</var></dt> - <dd>Currently available settings for the driver (frequency/power usage). - Values are in units of MHz and milliwatts. This is helpful for - understanding which settings are offered by which driver for debugging - purposes.</dd> - <dt id="debug.cpufreq.lowest"><var class="Va">debug.cpufreq.lowest</var></dt> - <dd>Lowest CPU frequency in MHz to offer to users. This setting is also - accessible via a tunable with the same name. This can be used to disable - very low levels that may be unusable on some systems.</dd> - <dt id="debug.cpufreq.verbose"><var class="Va">debug.cpufreq.verbose</var></dt> - <dd>Print verbose messages. This setting is also accessible via a tunable with - the same name.</dd> - <dt id="debug.hwpstate_pstate_limit"><var class="Va">debug.hwpstate_pstate_limit</var></dt> - <dd>If enabled, the AMD hwpstate driver limits administrative control of - P-states (including by <a class="Xr">powerd(8)</a>) to the value in the - 0xc0010061 MSR, known as "PStateCurLim[CurPstateLimit]." It is - disabled (0) by default. On some hardware, the limit register seems to - simply follow the configured P-state, which results in the inability to - ever raise the P-state back to P0 from a reduced frequency state.</dd> -</dl> -</section> -<section class="Sh"> -<h1 class="Sh" id="SUPPORTED_DRIVERS"><a class="permalink" href="#SUPPORTED_DRIVERS">SUPPORTED - DRIVERS</a></h1> -<p class="Pp">The following device drivers offer absolute frequency control via - the <code class="Nm">cpufreq</code> interface. Usually, only one of these - can be active at a time.</p> -<p class="Pp"></p> -<dl class="Bl-tag Bl-compact"> - <dt>acpi_perf</dt> - <dd>ACPI CPU performance states</dd> - <dt><a class="Xr">est(4)</a></dt> - <dd>Intel Enhanced SpeedStep</dd> - <dt>hwpstate</dt> - <dd>AMD Cool'n'Quiet2 used in K10 through Family 17h</dd> - <dt><a class="Xr">hwpstate_intel(4)</a></dt> - <dd>Intel SpeedShift driver</dd> - <dt>ichss</dt> - <dd>Intel SpeedStep for ICH</dd> - <dt>powernow</dt> - <dd>AMD PowerNow! and Cool'n'Quiet for K7 and K8</dd> - <dt>smist</dt> - <dd>Intel SMI-based SpeedStep for PIIX4</dd> -</dl> -<p class="Pp">The following device drivers offer relative frequency control and - have an additive effect:</p> -<p class="Pp"></p> -<dl class="Bl-tag Bl-compact"> - <dt>acpi_throttle</dt> - <dd>ACPI CPU throttling</dd> - <dt>p4tcc</dt> - <dd>Pentium 4 Thermal Control Circuitry</dd> -</dl> -</section> -<section class="Sh"> -<h1 class="Sh" id="KERNEL_INTERFACE"><a class="permalink" href="#KERNEL_INTERFACE">KERNEL - INTERFACE</a></h1> -<p class="Pp">Kernel components can query and set CPU frequencies through the - <code class="Nm">cpufreq</code> kernel interface. This involves obtaining a - <code class="Nm">cpufreq</code> device, calling - <a class="permalink" href="#cpufreq_levels"><code class="Fn" id="cpufreq_levels">cpufreq_levels</code></a>() - to get the currently available frequency levels, checking the current level - with <code class="Fn">cpufreq_get</code>(), and setting a new one from the - list with <code class="Fn">cpufreq_set</code>(). Each level may actually - reference more than one <code class="Nm">cpufreq</code> driver but kernel - components do not need to be aware of this. The - <var class="Va">total_set</var> element of <var class="Vt">struct - cf_level</var> provides a summary of the frequency and power for this level. - Unknown or irrelevant values are set to - <code class="Dv">CPUFREQ_VAL_UNKNOWN</code>.</p> -<p class="Pp" id="cpufreq_levels~2">The - <a class="permalink" href="#cpufreq_levels~2"><code class="Fn">cpufreq_levels</code></a>() - method takes a <code class="Nm">cpufreq</code> device and an empty array of - <var class="Fa">levels</var>. The <var class="Fa">count</var> value should - be set to the number of levels available and after the function completes, - will be set to the actual number of levels returned. If there are more - levels than <var class="Fa">count</var> will allow, it should return - <code class="Er">E2BIG</code>.</p> -<p class="Pp" id="cpufreq_get">The - <a class="permalink" href="#cpufreq_get"><code class="Fn">cpufreq_get</code></a>() - method takes a pointer to space to store a <var class="Fa">level</var>. - After successful completion, the output will be the current active level and - is equal to one of the levels returned by - <code class="Fn">cpufreq_levels</code>().</p> -<p class="Pp" id="cpufreq_set">The - <a class="permalink" href="#cpufreq_set"><code class="Fn">cpufreq_set</code></a>() - method takes a pointer a <var class="Fa">level</var> and attempts to - activate it. The <var class="Fa">priority</var> (i.e., - <code class="Dv">CPUFREQ_PRIO_KERN</code>) tells - <code class="Nm">cpufreq</code> whether to override previous settings while - activating this level. If <var class="Fa">priority</var> is higher than the - current active level, that level will be saved and overridden with the new - level. If a level is already saved, the new level is set without overwriting - the older saved level. If <code class="Fn">cpufreq_set</code>() is called - with a <code class="Dv">NULL</code> <var class="Fa">level</var>, the saved - level will be restored. If there is no saved level, - <code class="Fn">cpufreq_set</code>() will return - <code class="Er">ENXIO</code>. If <var class="Fa">priority</var> is lower - than the current active level's priority, this method returns - <code class="Er">EPERM</code>.</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="DRIVER_INTERFACE"><a class="permalink" href="#DRIVER_INTERFACE">DRIVER - INTERFACE</a></h1> -<p class="Pp">Kernel drivers offering hardware-specific CPU frequency control - export their individual settings through the <code class="Nm">cpufreq</code> - driver interface. This involves implementing these methods: - <code class="Fn">cpufreq_drv_settings</code>(), - <code class="Fn">cpufreq_drv_type</code>(), - <code class="Fn">cpufreq_drv_set</code>(), and - <code class="Fn">cpufreq_drv_get</code>(). Additionally, the driver must - attach a device as a child of a CPU device so that these methods can be - called by the <code class="Nm">cpufreq</code> framework.</p> -<p class="Pp" id="cpufreq_drv_settings">The - <a class="permalink" href="#cpufreq_drv_settings"><code class="Fn">cpufreq_drv_settings</code></a>() - method returns an array of currently available settings, each of type - <var class="Vt">struct cf_setting</var>. The driver should set unknown or - irrelevant values to <code class="Dv">CPUFREQ_VAL_UNKNOWN</code>. All the - following elements for each setting should be returned:</p> -<div class="Bd Pp Li"> -<pre>struct cf_setting { - int freq; /* CPU clock in MHz or 100ths of a percent. */ - int volts; /* Voltage in mV. */ - int power; /* Power consumed in mW. */ - int lat; /* Transition latency in us. */ - device_t dev; /* Driver providing this setting. */ -};</pre> -</div> -<p class="Pp">On entry to this method, <var class="Fa">count</var> contains the - number of settings that can be returned. On successful completion, the - driver sets it to the actual number of settings returned. If the driver - offers more settings than <var class="Fa">count</var> will allow, it should - return <code class="Er">E2BIG</code>.</p> -<p class="Pp" id="cpufreq_drv_type">The - <a class="permalink" href="#cpufreq_drv_type"><code class="Fn">cpufreq_drv_type</code></a>() - method indicates the type of settings it offers, either - <code class="Dv">CPUFREQ_TYPE_ABSOLUTE</code> or - <code class="Dv">CPUFREQ_TYPE_RELATIVE</code>. Additionally, the driver may - set the <code class="Dv">CPUFREQ_FLAG_INFO_ONLY</code> flag if the settings - it provides are information for other drivers only and cannot be passed to - <code class="Fn">cpufreq_drv_set</code>() to activate them.</p> -<p class="Pp" id="cpufreq_drv_set">The - <a class="permalink" href="#cpufreq_drv_set"><code class="Fn">cpufreq_drv_set</code></a>() - method takes a driver setting and makes it active. If the setting is invalid - or not currently available, it should return - <code class="Er">EINVAL</code>.</p> -<p class="Pp" id="cpufreq_drv_get">The - <a class="permalink" href="#cpufreq_drv_get"><code class="Fn">cpufreq_drv_get</code></a>() - method returns the currently-active driver setting. The - <var class="Vt">struct cf_setting</var> returned must be valid for passing - to <code class="Fn">cpufreq_drv_set</code>(), including all elements being - filled out correctly. If the driver cannot infer the current setting (even - by estimating it with - <a class="permalink" href="#cpu_est_clockrate"><code class="Fn" id="cpu_est_clockrate">cpu_est_clockrate</code></a>()) - then it should set all elements to - <code class="Dv">CPUFREQ_VAL_UNKNOWN</code>.</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="SEE_ALSO"><a class="permalink" href="#SEE_ALSO">SEE - ALSO</a></h1> -<p class="Pp"><a class="Xr">acpi(4)</a>, <a class="Xr">est(4)</a>, - <a class="Xr">timecounters(4)</a>, <a class="Xr">powerd(8)</a>, - <a class="Xr">sysctl(8)</a></p> -</section> -<section class="Sh"> -<h1 class="Sh" id="AUTHORS"><a class="permalink" href="#AUTHORS">AUTHORS</a></h1> -<p class="Pp"><span class="An">Nate Lawson</span> - <br/> - <span class="An">Bruno Ducrot</span> contributed the - <span class="Pa">powernow</span> driver.</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="BUGS"><a class="permalink" href="#BUGS">BUGS</a></h1> -<p class="Pp">The following drivers have not yet been converted to the - <code class="Nm">cpufreq</code> interface: <a class="Xr">longrun(4)</a>.</p> -<p class="Pp">Notification of CPU and bus frequency changes is not implemented - yet.</p> -<p class="Pp">When multiple CPUs offer frequency control, they cannot be set to - different levels and must all offer the same frequency settings.</p> -</section> -</div> -<table class="foot"> - <tr> - <td class="foot-date">April 4, 2022</td> - <td class="foot-os">FreeBSD 15.0</td> - </tr> -</table> |