This change should make Longhaul more compatible with
both ver. 2 and Powersaver processors. Voltage transitions
will be done before or after frequency transition. That depends
on direction of change. I don't know how to force conservative
governor when voltage scaling is enabled, so there is only
a warning for user. Minimal voltage is calculated in different
way now because in this way more power is saved at lower
multipliers.
Signed-off-by: Rafal Bilski <rafalbilski@interia.pl>
Signed-off-by: Dave Jones <davej@redhat.com>
CPU_FREQ_TABLE enables helper code and gets select'ed when it's required.
Building it as a module when it's not required doesn't seem to make much sense.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>
Eliminate flush_workqueue in cpufreq_governor(STOP) callpath. Using flush
there has a deadlock potential as in
http://uwsg.iu.edu/hypermail/linux/kernel/0611.3/1223.html
Also, cleanup the locking issues with do_dbs_timer delayed_work callback. As
it changes the CPU frequency using __cpufreq_target, it needs to have
policy_rwsem in write mode, which also protects it from hot plug.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>
Restructure the delayed_work callback in ondemand.
This eliminates the need for smp_processor_id in the callback function and
also helps in proper locking and avoiding flush_workqueue when stopping the
governor (done in subsequent patch).
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>
Yet another attempt to resolve cpufreq and hotplug locking issues.
Patchset has 3 patches:
* Rewrite the lock infrastructure of cpufreq using a per cpu rwsem.
* Minor restructuring of work callback in ondemand driver.
* Use the new cpufreq rwsem infrastructure in ondemand work.
This patch:
Convert policy->lock to rwsem and move it to per_cpu area.
This rwsem will protect against both changing/accessing policy
related parameters and CPU hot plug/unplug.
[malattia@linux.it: fix oops in kref_put()]
Cc: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Mattia Dongili <malattia@linux.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>
The hotplug CPU locking in cpufreq is horrendous. No-one seems to care
enough to fix it, so just remove it so that the 99.9% of the real world
users of this code can use cpufreq without being bothered by warnings.
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>
This is driver for Enhanced Powersaver which is present in VIA C7
processors. Beta tested by Jorgen (jorgen (at) greven dot dk).
Thanks! Based on documentation provided by Dave Jones (Thanks!)
and C7 Eden datasheet available from www.via.com.tw. Looks like all
these C7 Eden CPU's don't have P-states in BIOS. I know that 2
p-states is low, but Jorgen finds it usefull anyway because board
is passive cooled.
There are 3 different types of C7 processors (called brands):
0. C7-M - these processors can set any maultiplier between min and
max, any voltage between min and max.
1. C7 - only min and max states are supported. Voltage is different
for min and max states.
2. Eden - only min and max states are supported. Looks like this
brand can only change multiplier. Voltage seems to be the same for
min and max frequency.
Signed-off-by: Rafal Bilski <rafalbilski@interia.pl>
Signed-off-by: Dave Jones <davej@redhat.com>
Fix whitespace, braces, use kzalloc().
Cc: Dave Airlie <airlied@linux.ie>
Cc: Thomas Hellstrom <thomas@tungstengraphics.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>
This macro was used to save static registers before calling
sys_sigsuspend() and sys_sigreturn().
For the sys_sigreturn() case, there's no point to save them
since they have been already saved by setup_sigcontext()
before calling the signal handler.
For the sys_sigsuspend() case, I don't see any reasons...
Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
All the information in the MIPS c0_status register is priviledged.
Nothing that would constitute part of the thread context.
The one flag one could possibly argument about might be c0_status.fr
but none of the ABIs or tools or application software can make use
of it.
So for consistency with restore_sigcontext32(), which does not
restore c0_status register, this patch remove the saving part.
Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This trivial changes should decrease a lot the size of these
2 functions.
Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
