Commit Graph

9 Commits

Author SHA1 Message Date
Chumbalkar Nagananda
51555c0e91 [CPUFREQ] minor correction to cpu-freq documentation
I have been reading the documentation for cpufreq closely. Found a couple of
minor errors in the Documentation.

Signed-off-by: Naga Chumbalkar <nagananda.chumbalkar@hp.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2009-06-15 11:49:42 -04:00
Thomas Renninger
ed12978453 [CPUFREQ] Introduce /sys/devices/system/cpu/cpu*/cpufreq/cpuinfo_transition_latency
It's not only useful for the ondemand and conservative governors, but
also for userspace daemons to know about the HW transition latency of
the CPU.
It is especially useful for userspace to know about this value when
the ondemand or conservative governors are run. The sampling rate
control value depends on it and for userspace being able to set sane
tuning values there it has to know about the transition latency.

Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:31 -05:00
Thomas Renninger
62663ea822 ACPI: cpufreq: Remove deprecated /proc/acpi/processor/../performance proc entries
They were long enough set deprecated...

Update Documentation/cpu-freq/users-guide.txt:
The deprecated files listed there seen not to exist for some time anymore
already.

Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-02-04 00:12:24 -05:00
Paul Mundt
8a655053ca doc: Update sh cpufreq documentation.
The sh cpufreq driver is no longer limited to just the SH-3 and SH-4,
update the documentation to reflect this fact accordingly.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-12-22 18:44:47 +09:00
Robin Getz
121fe86bdf [CPUFREQ] Documentation: Add Blackfin to list of supported processors
Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-11-25 13:38:29 -05:00
Darrick J. Wong
605400a8ab [CPUFREQ] document the currently undocumented parts of the sysfs interface
There is a description of some of the sysfs files.  However, there are some
that are not mentioned in the documentation, so add them to the user's guide.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-04-28 16:27:08 -04:00
Russell King
9e2697ff37 [ARM] pxa: add cpufreq support
There have been patches hanging around for ages to add support for
cpufreq to PXA255 processors.  It's about time we applied one.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-01-26 15:07:52 +00:00
Mattia Dongili
9c9a43ed27 [CPUFREQ] return error when failing to set minfreq
I just stumbled on this bug/feature, this is how to reproduce it:

# echo 450000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq
# echo 450000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
# echo powersave > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
# cpufreq-info -p
450000 450000 powersave
# echo 1800000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq ; echo $?
0
# cpufreq-info -p
450000 450000 powersave

Here it is. The kernel refuses to set a min_freq higher than the
max_freq but it allows a max_freq lower than min_freq (lowering min_freq
also).

This behaviour is pretty straightforward (but undocumented) and it
doesn't return an error altough failing to accomplish the requested
action (set min_freq).
The problem (IMO) is basically that userspace is not allowed to set a
full policy atomically while the kernel always does that thus it must
enforce an ordering on operations.

The attached patch returns -EINVAL if trying to increase frequencies
starting from scaling_min_freq and documents the correct ordering of writes.

Signed-off-by: Mattia Dongili <malattia@linux.it>
Signed-off-by: Dominik Brodowski <linux at dominikbrodowski.net>
Signed-off-by: Dave Jones <davej@redhat.com>

--
2006-07-31 18:37:05 -04:00
Linus Torvalds
1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00