thinkpad-acpi: bump up version to 0.23

[safe/jmp/linux-2.6] / Documentation / cpu-freq / user-guide.txt

diff --git a/Documentation/cpu-freq/user-guide.txt b/Documentation/cpu-freq/user-guide.txt
index 7fedc00..75f4119 100644 (file)
--- a/Documentation/cpu-freq/user-guide.txt
+++ b/Documentation/cpu-freq/user-guide.txt
@@ -23,6 +23,7 @@ Contents:
 1.3 sparc64
 1.4 ppc
 1.5 SuperH
+1.6 Blackfin
 
 2. "Policy" / "Governor"?
 2.1 Policy
@@ -45,6 +46,7 @@ The following ARM processors are supported by cpufreq:
 ARM Integrator
 ARM-SA1100
 ARM-SA1110
+Intel PXA
 
 
 1.2 x86
@@ -91,10 +93,19 @@ Several "PowerBook" and "iBook2" notebooks are supported.
 1.5 SuperH
 ----------
 
-The following SuperH processors are supported by cpufreq:
+All SuperH processors supporting rate rounding through the clock
+framework are supported by cpufreq.
 
-SH-3
-SH-4
+1.6 Blackfin
+------------
+
+The following Blackfin processors are supported by cpufreq:
+
+BF522, BF523, BF524, BF525, BF526, BF527, Rev 0.1 or higher
+BF531, BF532, BF533, Rev 0.3 or higher
+BF534, BF536, BF537, Rev 0.2 or higher
+BF561, Rev 0.3 or higher
+BF542, BF544, BF547, BF548, BF549, Rev 0.1 or higher
 
 
 2. "Policy" / "Governor" ?
@@ -141,6 +152,18 @@ cpuinfo_min_freq :         this file shows the minimum operating
                                frequency the processor can run at(in kHz) 
 cpuinfo_max_freq :             this file shows the maximum operating
                                frequency the processor can run at(in kHz) 
+cpuinfo_transition_latency     The time it takes on this CPU to
+                               switch between two frequencies in nano
+                               seconds. If unknown or known to be
+                               that high that the driver does not
+                               work with the ondemand governor, -1
+                               (CPUFREQ_ETERNAL) will be returned.
+                               Using this information can be useful
+                               to choose an appropriate polling
+                               frequency for a kernel governor or
+                               userspace daemon. Make sure to not
+                               switch the frequency too often
+                               resulting in performance loss.
 scaling_driver :               this file shows what cpufreq driver is
                                used to set the frequency on this CPU
 
@@ -153,11 +176,28 @@ scaling_governor,         and by "echoing" the name of another
                                that some governors won't load - they only
                                work on some specific architectures or
                                processors.
-scaling_min_freq and 
+
+cpuinfo_cur_freq :             Current speed of the CPU, in KHz.
+
+scaling_available_frequencies : List of available frequencies, in KHz.
+
+scaling_min_freq and
 scaling_max_freq               show the current "policy limits" (in
                                kHz). By echoing new values into these
                                files, you can change these limits.
+                               NOTE: when setting a policy you need to
+                               first set scaling_max_freq, then
+                               scaling_min_freq.
+
+affected_cpus :                        List of CPUs that require software coordination
+                               of frequency.
 
+related_cpus :                 List of CPUs that need some sort of frequency
+                               coordination, whether software or hardware.
+
+scaling_driver :               Hardware driver for cpufreq.
+
+scaling_cur_freq :             Current frequency of the CPU, in KHz.
 
 If you have selected the "userspace" governor which allows you to
 set the CPU operating frequency to a specific value, you can read out
@@ -167,19 +207,3 @@ scaling_setspeed.          By "echoing" a new frequency into this
                                you can change the speed of the CPU,
                                but only within the limits of
                                scaling_min_freq and scaling_max_freq.
-                               
-
-3.2 Deprecated Interfaces
--------------------------
-
-Depending on your kernel configuration, you might find the following 
-cpufreq-related files:
-/proc/cpufreq
-/proc/sys/cpu/*/speed
-/proc/sys/cpu/*/speed-min
-/proc/sys/cpu/*/speed-max
-
-These are files for deprecated interfaces to cpufreq, which offer far
-less functionality. Because of this, these interfaces aren't described
-here.
-