cpufreq: interactive: allow arbitrary speed / delay mappings

Accept a string of delays and speeds at which to apply the delay before
raising each step above hispeed. For example, "80000 1300000:200000
1500000:40000" means that the delay at or above 1GHz, until 1.3GHz is 80 msecs,
the delay until 1.5GHz is 200 msecs and the delay at or above 1.5GHz is 40
msecs when hispeed_freq is 1GHz.

[toddpoynor@google.com: add documentation]
Change-Id: Ifeebede8b1acbdd0a53e5c6916bccbf764dc854f
Signed-off-by: Minsung Kim <ms925.kim@samsung.com>
cpufreq: interactive: add io_is_busy interface

Previously the idle time returned from get_cpu_idle_time_us included the
iowait time. So the iowait time was always calculated as idle time.

But now the idle time returned from get_cpu_idle_time_us does not include
the iowait time anymore because of below commit which cause the iowait time
always calculated as busy time:
    6beea0c nohz: Fix update_ts_time_stat idle accounting

Add the io_is_busy interface, as does the ondemand governor, and let the user
configure the iowait time as busy or idle through the io_is_busy sysfs
interface.

By default, io_is_busy is disabled.

[toddpoynor@google.com: minor updates]
Change-Id: If7d70ff864c43bc9c8d7fd7cfc66f930d339f9b4
Signed-off-by: Lianwei Wang <lian-wei.wang@motorola.com>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
cpufreq: interactive: fix crash on error paths in get_tokenized_data

Use separate variable for error code, free proper pointer.

Change-Id: Ia83cccb195997789ac6afbf5b8761f7b278196d6
Reported-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
cpufreq: interactive: base above_hispeed_delay on target freq, not current

Time to wait should be based on the intended target speed, not the
actual speed (which may be held high by another CPU).

Change-Id: Ifc5bb55d06adddb9a02af90af05398a78f282272
Reported-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
cpufreq: interactive: fix uninitialized spinlock

Add missing spinlock init

Backtrace:
[<c0011ce4>] (dump_backtrace+0x0/0x10c) from [<c0662a68>] (dump_stack+0x18/0x1c)
 r6:00000032 r5:c0bd09ec r4:e6848000 r3:00000000
[<c0662a50>] (dump_stack+0x0/0x1c) from [<c06670b0>] (spin_dump+0x80/0x94)
[<c0667030>] (spin_dump+0x0/0x94) from [<c06670f0>] (spin_bug+0x2c/0x30)
 r5:c08f91fc r4:c0bd09ec
[<c06670c4>] (spin_bug+0x0/0x30) from [<c0245f74>] (do_raw_spin_unlock+0x88/0xcc)
 r5:e547bac0 r4:c0bd09ec
[<c0245eec>] (do_raw_spin_unlock+0x0/0xcc) from [<c066c9cc>] (_raw_spin_unlock_irqrestore+0x14/0x40)
 r5:e547bac0 r4:60000013
[<c066c9b8>] (_raw_spin_unlock_irqrestore+0x0/0x40) from [<c044b884>] (store_above_hispeed_delay+0x6c/0x80)
 r4:c0b4cf78 r3:00000007
[<c044b818>] (store_above_hispeed_delay+0x0/0x80) from [<c0235d24>] (kobj_attr_store+0x1c/0x28)
 r7:e68ff000 r6:00000032 r5:e58137c0 r4:e61cde80
[<c0235d08>] (kobj_attr_store+0x0/0x28) from [<c0156b78>] (sysfs_write_file+0x104/0x184)
[<c0156a74>] (sysfs_write_file+0x0/0x184) from [<c0100680>] (vfs_write+0xb0/0x140)
[<c01005d0>] (vfs_write+0x0/0x140) from [<c0100900>] (sys_write+0x44/0x70)
 r8:00000000 r7:00000004 r6:00000032 r5:bee43c90 r4:e5600300
[<c01008bc>] (sys_write+0x0/0x70) from [<c000e400>] (ret_fast_syscall+0x0/0x30)
 r9:e6842000 r8:c000e584 r6:00000032 r5:bee43c90 r4:00000009

Change-Id: I80a1e0b3fecb24adba501ff44f568479deeff7fa
Signed-off-by: Minsung Kim <ms925.kim@samsung.com>
cpufreq: interactive: handle errors from cpufreq_frequency_table_target

Add checks for error return from cpufreq_frequency_table_target, and be
less noisy on the existing call with an error check.  CPU hotplug and
system shutdown may cause this call to return -EINVAL.

Bug: 8613560
Change-Id: Id78d8829920462c0db1c7e14e717d91740d6cb44
Signed-off-by: Todd Poynor <toddpoynor@google.com>
cpufreq: interactive: reduce chance of zero time delta on load eval

Reschedule load sampling timer after timestamp of sample start taken,
hold spinlock across entire sequence to avoid preemption.  Avoid the
WARN for zero time delta in the load sampling timer function.

Change-Id: Idc10a756f09141decb6df92669521a1ebf0dbc10
Signed-off-by: Todd Poynor <toddpoynor@google.com>
cpufreq: interactive: avoid underflow on active time calculation

Check for idle time delta less than elapsed time delta, avoid
underflow computing active time.

Change-Id: I3e4c6ef1ad794eec49ed379c0c50fa727fd6ad28
Signed-off-by: Minsung Kim <ms925.kim@samsung.com>
cpufreq: interactive: fix race on cpufreq TRANSITION notifier

The cpufreq TRANSTION notifier callback does not check the
governor_enabled state on affected CPUS, which will case
kernel panic in update_load because the policy object maybe
NULL or invalid when governor_enabled is false.

Change-Id: Ie0f1718124f61e2f9b5da57abc6981ada5b83908
Signed-off-by: Lianwei Wang <a22439@motorola.com>
cpufreq: interactive: resched timer if max freq raised

When the policy max freq is raised, and before the timer is
rescheduled in idle callback, the cpu freq may stuck at a
lower freq.

The target_freq shall be updated too, else on a high load
situation, the new_freq is always equal to target_freq and
which will cause freq stuck at a lower freq too.

Reschedule the timer on gov limits callback.

Change-Id: I6c187001ab43e859731429b64f75a74eebc37a24
Signed-off-by: Lianwei Wang <a22439@motorola.com>
cpufreq: interactive: fix show_target_loads and show_above_hispeed_delay

Remove a trailing whitespace from target_loads and above_hispeed_delay. Problem
happens when user-space program tried to restore parameters that saved before
changing parameters. In this case was returned error(EINVAL).

Change-Id: I5a74e3824602cd6f2b74651adda5ec1b627e61e9
Signed-off-by: Minsung Kim <ms925.kim@samsung.com>
block: row-iosched idling triggered by readahead pages

In the current implementation idling is triggered only by request
insertion frequency. This heuristic is not very accurate and may hit
random requests that shouldn't trigger idling. This patch uses the
PG_readahead flag in struct page's flags, which indicates that the page
is part of a readahead window, to start idling upon dispatch of a request
associated with a readahead page.

The above readehead flag is used together with the existing
insertion-frequency trigger. The frequency timer will catch read requests
which are not part of a readahead window, but are still part of a
sequential stream (and therefore dispatched in small time intervals).

Change-Id: Icb7145199c007408de3f267645ccb842e051fd00
Signed-off-by: Lee Susman <lsusman@codeaurora.org>
block: row: Remove warning massage from add_request

Regular priority queues is marked as "starved" if it skipped a dispatch
due to being empty. When a new request is added to a "starved" queue
it will be marked as urgent.
The removed WARN_ON was warning about an impossible case when a regular
priority (read) queue was marked as starved but wasn't empty. This is
a possible case due to the bellow:
If the device driver fetched a read request that is pending for
transmission and an URGENT request arrives, the fetched read will be
reinserted back to the scheduler. Its possible that the queue it will be
reinserted to was marked as "starved" in the meanwhile due to being empty.

CRs-fixed: 517800
Change-Id: Iaae642ea0ed9c817c41745b0e8ae2217cc684f0c
Signed-off-by: Tatyana Brokhman <tlinder@codeaurora.org>
msm: kgsl: Option to disable GPU fault tolerance

When GPU Fault tolerance is set to KGSL_FT_OFF do not run
fault tolerance. When we turn off fault tolerance
a) If GPU continues executing commands then
   GPU stall detection is false
b) If GPU does not execute further commands then
   GPU stall detection is correct

When GPU stall detection is suspected to be false,
we can use this option to confirm stall detection.

Change-Id: Iac4d235377df015db223df9ec5597fb43d4c8878
Signed-off-by: Tarun Karra <tkarra@codeaurora.org>
msm: kgsl: don't store rptr in struct adreno_ringbuffer

Since the rptr is written by the GPU, there's no point
in keeping a copy in the ringbuffer struct where it will
likely be out of date. If you need to look at the ringbuffer,
read it into a local variable with adreno_get_rptr().

Change-Id: Ibf1ba0b9c71a93f65a5c85a58328b2202a27af3f
Signed-off-by: Jeremy Gebben <jgebben@codeaurora.org>
mm: pass readahead info down to the i/o scheduler

Some i/o schedulers (i.e. row-iosched, cfq-iosched) deploy an idling
algorithm in order to be better synced with the readahead algorithm.
Idling is a prediction algorithm for incoming read requests.

In this patch we mark pages which are part of a readahead window, by
setting a newly introduced flag. With this flag, the i/o scheduler can
identify a request which is associated with a readahead page. This
enables the i/o scheduler's idling mechanism to be en-sync with the
readahead mechanism and, in turn, can increase read throughput.

Change-Id: I0654f23315b6d19d71bcc9cc029c6b281a44b196
Signed-off-by: Lee Susman <lsusman@codeaurora.org>
msm: cpufreq: Ensure cpufreq change happens on corresponding CPU

* This removes stuttering a few ppl were experiencing -imoseyon

Checking the cpus_allowed mask of the current thread before changing the
frequency doesn't guarantee that the rest of the execution will continue on
the same CPU. The only way to guarantee this is to schedule a work on the
specific CPU and also prevent hotplug  of that CPU (already done by
existing code).

Change-Id: I51a02fcc777a47d3c16f2d83c47e96f2c59f7ae6
Signed-off-by: Saravana Kannan <skannan@codeaurora.org>
msm: krait-regulator-pmic: Add krait-regulator-pmic driver

Read the register configurations of regulators in the gang and
bug if the gang is not setup correctly.

Importantly, fix the voltage overshoots observed during PFM-PWM
transitions by implementing the following steps.

PFM -> PWM
After the buck is set to PWM mode, wait 50uS and then set the PWM
current limit to 3.5A.

PWM -> PFM
After the buck is set to pfm mode, immediately lower the PWM current limit
to 2A (no delay required).

Change-Id: I15af09aaf8427e75253a4e12878ee1f0a1265454
Signed-off-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>

Conflicts:

	arch/arm/mach-msm/Makefile
msm: krait-regulator: switch mode on the same cpu

The driver currently runs LDO-BHS mode switches while possibly
running on a different CPU. The CPU for which the mode switch is
issued could be running its SPM sequence as a part of going in or
coming out of power collapse. The LDO-BHS switching executed from a
different CPU could race with the mode switches done in SPM sequence
leaving the CPU in a bad state.

Fix this by executing LDO-BHS mode switches on the target CPU. This
guarantees that the SPM sequence won't be running on that CPU while
changing modes.

CRs-Fixed: 523449
Change-Id: I863ce3bcd6dd9ba3155c4573071f01e7a020ef48
Signed-off-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>
msm: krait-regulator: rename online to reg_en

The online variable is confusing, since it does not mean whether
the core is online or offline. It actually used to indicate whether
the regulator is enabled or disabled.
Change the variable name to indicate so.

Change-Id: I20c270162df57cf81c17e808d383880b5b2e4eef
Signed-off-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>