Commit Graph

304 Commits

Author SHA1 Message Date
Dmitry Osipenko
fee22854c0 PM / devfreq: tegra30: Tune up MCCPU boost-down coefficient
MCCPU boosts up very aggressively by 800% and boosts down very mildly by
10%. This doesn't work well when system is idling because the very slow
de-boosting results in lots of consecutive-down interrupts, in result
memory stays clocked high and CPU doesn't enter deepest idling state
instead of keeping memory at lowest freq and having CPU cluster turned
off. A more faster de-boosting fixes the case of idling system and doesn't
affect the case of an active system.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2019-11-06 12:04:01 +09:00
Dmitry Osipenko
f61ee20106 PM / devfreq: tegra30: Support variable polling interval
The ACTMON governor is interrupt-driven and currently hardware's polling
interval is fixed to 16ms in the driver. Devfreq supports variable polling
interval by the generic governors, let's re-use the generic interface for
changing of the polling interval. Now the polling interval can be changed
dynamically via /sys/class/devfreq/devfreq0/polling_interval.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2019-11-06 12:04:01 +09:00
Dmitry Osipenko
5c0f6c7959 PM / devfreq: Add new interrupt_driven flag for governors
Currently interrupt-driven governors (like NVIDIA Tegra30 ACTMON governor)
are used to set polling_ms=0 in order to avoid periodic polling of device
status by devfreq core. This means that polling interval can't be changed
by userspace for such governors.

The new governor flag allows interrupt-driven governors to convey that
devfreq core shouldn't perform polling of device status and thus generic
devfreq polling interval could be supported by these governors now.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2019-11-06 12:04:01 +09:00
Dmitry Osipenko
28615e37be PM / devfreq: tegra30: Use kHz units for dependency threshold
The dependency threshold designates a memory activity level below which
CPU's frequency isn't accounted. Currently the threshold is given in
"memory cycle" units and that value depends on the polling interval which
is fixed to 12ms in the driver. Later on we'd want to add support for a
variable polling interval and thus the threshold value either needs to be
scaled in accordance to the polling interval or it needs to be represented
in a units that do not depend on the polling interval.

It is nicer to have threshold value being defined independently of the
polling interval, thus this patch converts the dependency threshold units
from "cycle" to "kHz". Having this change as a separate-preparatory patch
will make easier to follow further patches.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2019-11-06 12:04:01 +09:00
Dmitry Osipenko
88ec816446 PM / devfreq: tegra30: Disable consecutive interrupts when appropriate
Consecutive interrupts should be disabled when boosting is completed.

Currently the disabling of "lower" interrupt happens only for MCCPU
monitor that uses dependency threshold, but even in a case of MCCPU the
interrupt isn't getting disabled if CPU's activity is above the threshold.
This results in a lot of dummy interrupt requests. The boosting feature is
used by both MCCPU and MCALL, boosting should be stopped once it reaches 0
for both of the monitors and regardless of the activity level.

The boosting stops to grow once the maximum limit is hit and thus the
"upper" interrupt needs to be disabled when the limit is reached.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2019-11-06 12:04:01 +09:00
Dmitry Osipenko
333abefb28 PM / devfreq: tegra30: Don't enable already enabled consecutive interrupts
Consecutive up/down interrupt-bit is set in the interrupt status register
only if that interrupt was previously enabled. Thus enabling the already
enabled interrupt doesn't do much for us.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2019-11-06 12:04:01 +09:00
Dmitry Osipenko
9cff217778 PM / devfreq: tegra30: Include appropriate header
It's not very correct to include mod_devicetable.h for the OF device
drivers and of_device.h should be included instead.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Tested-by: Peter Geis <pgwipeout@gmail.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2019-11-06 12:04:01 +09:00
Dmitry Osipenko
b87dea3bba PM / devfreq: tegra30: Constify structs
Constify unmodifiable structs, for consistency.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Tested-by: Peter Geis <pgwipeout@gmail.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2019-11-06 12:04:01 +09:00
Dmitry Osipenko
61d9320841 PM / devfreq: tegra30: Don't enable consecutive-down interrupt on startup
The consecutive-down event tells that we should perform frequency
de-boosting, but boosting is in a reset state on start and hence the
event won't do anything useful for us and it will be just a dummy
interrupt request.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Tested-by: Peter Geis <pgwipeout@gmail.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2019-11-06 12:04:01 +09:00
Dmitry Osipenko
1426655827 PM / devfreq: tegra30: Reset boosting on startup
Governor could be stopped while boosting is active. We have assumption
that everything is reset on governor's restart, including the boosting
value, which was missed.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Tested-by: Peter Geis <pgwipeout@gmail.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2019-11-06 12:04:01 +09:00
Dmitry Osipenko
6f2a35d65b PM / devfreq: tegra30: Move clk-notifier's registration to governor's start
There is no point in receiving of the notifications while governor is
stopped, let's keep them disabled like we do for the CPU freq-change
notifications. This also fixes a potential use-after-free bug if
notification happens after device's removal.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Tested-by: Peter Geis <pgwipeout@gmail.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2019-11-06 12:04:00 +09:00
Dmitry Osipenko
11eb6ec5c0 PM / devfreq: tegra30: Use CPUFreq notifier
The CPU's client need to take into account that CPUFreq may change
while memory activity not, staying high. Thus an appropriate frequency
notifier should be used in addition to the clk-notifier.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Tested-by: Peter Geis <pgwipeout@gmail.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2019-11-06 12:04:00 +09:00
Dmitry Osipenko
0ce3884654 PM / devfreq: tegra30: Use kHz units uniformly in the code
Part of the code uses Hz units and the other kHz, let's switch to kHz
everywhere for consistency. A small benefit from this change (besides
code's cleanup) is that now powertop utility correctly displays devfreq's
stats, for some reason it expects them to be in kHz.

Tested-by: Peter Geis <pgwipeout@gmail.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2019-11-06 12:04:00 +09:00
Dmitry Osipenko
53b4b2aeee PM / devfreq: tegra30: Fix integer overflow on CPU's freq max out
There is another kHz-conversion bug in the code, resulting in integer
overflow. Although, this time the resulting value is 4294966296 and it's
close to ULONG_MAX, which is okay in this case.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Tested-by: Peter Geis <pgwipeout@gmail.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2019-11-06 12:04:00 +09:00
Dmitry Osipenko
e7955a34a2 PM / devfreq: tegra30: Drop write-barrier
There is no need in a write-barrier now, given that interrupt masking is
handled by CPU's GIC now. Hence we know exactly that interrupt won't fire
after stopping the devfreq's governor. In other cases we don't care about
potential buffering of the writes to hardware and thus there is no need to
stall CPU.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Tested-by: Peter Geis <pgwipeout@gmail.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2019-11-06 12:04:00 +09:00
Dmitry Osipenko
7296443b90 PM / devfreq: tegra30: Handle possible round-rate error
The EMC clock rate rounding technically could fail, hence let's handle
the error cases properly.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Tested-by: Peter Geis <pgwipeout@gmail.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2019-11-06 12:04:00 +09:00
Dmitry Osipenko
d49eeb1e83 PM / devfreq: tegra30: Keep interrupt disabled while governor is stopped
There is no real need to keep interrupt always-enabled, will be nicer
to keep it disabled while governor is inactive.

Suggested-by: Thierry Reding <thierry.reding@gmail.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Tested-by: Peter Geis <pgwipeout@gmail.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2019-11-06 12:04:00 +09:00
Dmitry Osipenko
dccdea01ad PM / devfreq: tegra30: Change irq type to unsigned int
IRQ numbers are always positive, hence the corresponding variable should
be unsigned to keep types consistent. This is a minor change that cleans
up code a tad more.

Suggested-by: Thierry Reding <thierry.reding@gmail.com>
Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Tested-by: Peter Geis <pgwipeout@gmail.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2019-11-06 12:04:00 +09:00
Marek Szyprowski
1f125dee4f PM / devfreq: exynos-ppmu: remove useless assignment
The error code is propagated to the caller, so there is no need to keep
it additionally in the unused variable.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2019-11-06 12:04:00 +09:00
Leonard Crestez
2abb0d5268 PM / devfreq: Lock devfreq in trans_stat_show
There is no locking in this sysfs show function so stats printing can
race with a devfreq_update_status called as part of freq switching or
with initialization.

Also add an assert in devfreq_update_status to make it clear that lock
must be held by caller.

Fixes: 39688ce6fa ("PM / devfreq: account suspend/resume for stats")
Cc: stable@vger.kernel.org
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2019-11-06 12:04:00 +09:00
Leonard Crestez
d68adc8f85 PM / devfreq: Check NULL governor in available_governors_show
The governor is initialized after sysfs attributes become visible so in
theory the governor field can be NULL here.

Fixes: bcf23c79c4 ("PM / devfreq: Fix available_governor sysfs")
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2019-11-06 12:03:59 +09:00
Matthias Kaehlcke
df4d7b1451 PM / devfreq: Make log message more explicit when devfreq device already exists
Before creating a new devfreq device devfreq_add_device() checks
if there is already a devfreq dev associated with the requesting
device (parent). If that's the case the function rejects to create
another devfreq dev for that parent and logs an error. The error
message is very unspecific, make it a bit more explicit.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2019-11-06 12:03:59 +09:00
MyungJoo Ham
0465814831 PM / devfreq: passive: fix compiler warning
The recent commit of
PM / devfreq: passive: Use non-devm notifiers
had incurred compiler warning, "unused variable 'dev'".

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-26 21:37:37 +09:00
Leonard Crestez
0ef7c7cce4 PM / devfreq: passive: Use non-devm notifiers
The devfreq passive governor registers and unregisters devfreq
transition notifiers on DEVFREQ_GOV_START/GOV_STOP using devm wrappers.

If devfreq itself is registered with devm then a warning is triggered on
rmmod from devm_devfreq_unregister_notifier. Call stack looks like this:

	devm_devfreq_unregister_notifier+0x30/0x40
	devfreq_passive_event_handler+0x4c/0x88
	devfreq_remove_device.part.8+0x6c/0x9c
	devm_devfreq_dev_release+0x18/0x20
	release_nodes+0x1b0/0x220
	devres_release_all+0x78/0x84
	device_release_driver_internal+0x100/0x1c0
	driver_detach+0x4c/0x90
	bus_remove_driver+0x7c/0xd0
	driver_unregister+0x2c/0x58
	platform_driver_unregister+0x10/0x18
	imx_devfreq_platdrv_exit+0x14/0xd40 [imx_devfreq]

This happens because devres_release_all will first remove all the nodes
into a separate todo list so the nested devres_release from
devm_devfreq_unregister_notifier won't find anything.

Fix the warning by calling the non-devm APIS for frequency notification.
Using devm wrappers is not actually useful for a governor anyway: it
relies on the devfreq core to correctly match the GOV_START/GOV_STOP
notifications.

Fixes: 996133119f ("PM / devfreq: Add new passive governor")
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-25 12:47:31 +09:00
Kamil Konieczny
4294a779bd PM / devfreq: exynos-bus: Convert to use dev_pm_opp_set_rate()
Reuse opp core code for setting bus clock and voltage. As a side
effect this allow usage of coupled regulators feature (required
for boards using Exynos5422/5800 SoCs) because dev_pm_opp_set_rate()
uses regulator_set_voltage_triplet() for setting regulator voltage
while the old code used regulator_set_voltage_tol() with fixed
tolerance. This patch also removes no longer needed parsing of DT
property "exynos,voltage-tolerance" (no Exynos devfreq DT node uses
it). After applying changes both functions exynos_bus_passive_target()
and exynos_bus_target() have the same code, so remove
exynos_bus_passive_target(). In exynos_bus_probe() replace it with
exynos_bus_target.

Signed-off-by: Kamil Konieczny <k.konieczny@partner.samsung.com>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-25 12:46:48 +09:00
Kamil Konieczny
2c2b20e0da PM / devfreq: exynos-bus: Correct clock enable sequence
Regulators should be enabled before clocks to avoid h/w hang. This
require change in exynos_bus_probe() to move exynos_bus_parse_of()
after exynos_bus_parent_parse_of() and change in error handling.
Similar change is needed in exynos_bus_exit() where clock should be
disabled before regulators.

Signed-off-by: Kamil Konieczny <k.konieczny@partner.samsung.com>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-25 12:46:07 +09:00
Krzysztof Kozlowski
e2fc1677ee PM / devfreq: Correct devm_devfreq_remove_device() documentation
Correct the documentation for devm_devfreq_remove_device() argument.

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-25 12:45:34 +09:00
Lukasz Luba
1dd62c66d3 PM / devfreq: events: extend events by type of counted data
This patch adds posibility to choose what type of data should be counted
by the PPMU counter. Now the type comes from DT where the event has been
defined. When there is no 'event-data-type' the default value is used,
which is 'read+write data in bytes'.
It is needed when you want to know not only read+write data bytes but
i.e. only write data in byte, or number of read requests, etc.

Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
[Updated property by MyungJoo. data_type --> event_type]
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-25 12:44:38 +09:00
Lukasz Luba
0ae9c3213c PM / devfreq: exynos-events: change matching code during probe
The patch changes the way how the 'ops' gets populated for different
device versions. The matching function now uses 'of_device_id' in order
to identify the device type.

Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-25 12:36:47 +09:00
Arnd Bergmann
23ca7d2503 PM / devfreq: tegra20: add COMMON_CLK dependency
Compile-testing the new driver on platforms without CONFIG_COMMON_CLK
leads to a link error:

drivers/devfreq/tegra20-devfreq.o: In function `tegra_devfreq_target':
tegra20-devfreq.c:(.text+0x288): undefined reference to `clk_set_min_rate'

Add a dependency on COMMON_CLK to avoid this.

Fixes: 1d39ee8dad6d ("PM / devfreq: Introduce driver for NVIDIA Tegra20")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-24 20:11:12 +09:00
Lukasz Luba
5f8669639f PM / devfreq: events: add Exynos PPMU new events
Define new performance events supported by Exynos5422 SoC counters.
The counters are built-in in Dynamic Memory Controller and provide
information regarding memory utilization.

Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-24 20:11:12 +09:00
Ezequiel Garcia
7544fd7f38 PM / devfreq: Fix kernel oops on governor module load
A bit unexpectedly (but still documented), request_module may
return a positive value, in case of a modprobe error.
This is currently causing issues in the devfreq framework.

When a request_module exits with a positive value, we currently
return that via ERR_PTR. However, because the value is positive,
it's not a ERR_VALUE proper, and is therefore treated as a
valid struct devfreq_governor pointer, leading to a kernel oops.

Fix this by returning -EINVAL if request_module returns a positive
value.

Fixes: b53b012805 ("PM / devfreq: Fix static checker warning in try_then_request_governor")
Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-24 20:11:12 +09:00
Gaël PORTAY
0a453aca94 PM / devfreq: rk3399_dmc: Fix spelling typo
Reorder 'i' and 'v' in "drvier".

Signed-off-by: Gaël PORTAY <gael.portay@collabora.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-24 20:11:12 +09:00
Gaël PORTAY
2c09083293 PM / devfreq: Fix spelling typo
Add missing 'r' in "monitoing".

Signed-off-by: Gaël PORTAY <gael.portay@collabora.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-24 20:11:12 +09:00
Dmitry Osipenko
d196175ed8 PM / devfreq: Introduce driver for NVIDIA Tegra20
Add devfreq driver for NVIDIA Tegra20 SoC's. The driver periodically
reads out Memory Controller counters and adjusts memory frequency based
on the memory clients activity.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
[Removed MAINTAINERS updates by MyungJoo so that it can be sent elsewhere.]
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-24 20:11:12 +09:00
Dmitry Osipenko
2360175291 PM / devfreq: tegra: Rename tegra-devfreq.c to tegra30-devfreq.c
In order to reflect that driver serves NVIDIA Tegra30 and later SoC
generations, let's rename the driver's source file to "tegra30-devfreq.c".
This will make driver files to look more consistent after addition of a
driver for Tegra20.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-24 20:11:12 +09:00
Dmitry Osipenko
35f8dbc727 PM / devfreq: tegra: Enable COMPILE_TEST for the driver
The driver's compilation doesn't have any specific dependencies, hence
the COMPILE_TEST option can be supported in Kconfig.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-24 20:11:12 +09:00
Dmitry Osipenko
1ac3474885 PM / devfreq: tegra: Support Tegra30
The devfreq driver can be used on Tegra30 without any code change and
it works perfectly fine, the default Tegra124 parameters are good enough
for Tegra30.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
[Modified by MyungJoo to depends on Tegra30/114/124/210 only]
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-24 20:11:12 +09:00
Dmitry Osipenko
546ff09381 PM / devfreq: tegra: Reconfigure hardware on governor's restart
Move hardware configuration to governor's start/resume methods.
This allows to re-initialize hardware counters and reconfigure
cleanly if governor was stopped/paused. That is needed because we
are not aware of all hardware changes that happened while governor
was stopped and the paused state may get out of sync with reality,
hence it's better to start with a clean slate after the pause. In
a result there is no memory bandwidth starvation after resume from
suspend-to-ram that results in display controller underflowing that
happens on resume because of improper decision made by devfreq about
the required memory frequency. This change also cleans up code a tad
by moving hardware-configuration code into a single location.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-24 20:11:12 +09:00
Dmitry Osipenko
5a7e10c895 PM / devfreq: tegra: Move governor registration to driver's probe
There is no need to register the ACTMON's governor separately from
the driver, hence let's move the registration into the driver's probe
function for consistency and to make code cleaner a tad.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-24 20:11:12 +09:00
Dmitry Osipenko
386789ebbd PM / devfreq: tegra: Mark ACTMON's governor as immutable
The ACTMON's governor supports only the Tegra's devfreq device and there
is no need to use any other governor, hence let's mark Tegra governor as
immutable to permanently stick it with Tegra's devfreq device.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-24 20:11:12 +09:00
Dmitry Osipenko
151531f79a PM / devfreq: tegra: Avoid inconsistency of current frequency value
The frequency value potentially could change in-between. It doesn't
cause any real problem at all right now, but that could change in the
future. Hence let's avoid the inconsistency.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-24 20:11:12 +09:00
Dmitry Osipenko
8fda5c1fab PM / devfreq: tegra: Clean up driver's probe / remove
Reset hardware, disable ACTMON clock, release OPP's and handle all
possible error cases correctly, maintaining the correct tear down
order. Also use devm_platform_ioremap_resource() which is now available
in the kernel.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-24 20:11:12 +09:00
Dmitry Osipenko
7514dd05ea PM / devfreq: tegra: Properly disable interrupts
There is no guarantee that interrupt handling isn't running in parallel
with tegra_actmon_disable_interrupts(), hence it is necessary to protect
DEV_CTRL register accesses and clear IRQ status with ACTMON's IRQ being
disabled in the Interrupt Controller in order to ensure that device
interrupt is indeed being disabled.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-24 20:11:12 +09:00
Dmitry Osipenko
dd3f2616bb PM / devfreq: tegra: Drop primary interrupt handler
There is no real need in the primary interrupt handler, hence move
everything to the secondary (threaded) handler. In a result locking
is consistent now and there are no potential races with the interrupt
handler because it is protected with the devfreq's mutex.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-24 20:11:12 +09:00
Dmitry Osipenko
b061312f4b PM / devfreq: tegra: Don't set EMC clock rate to maximum on probe
There is no real benefit from doing so, hence let's drop that rate setting
for consistency.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-24 20:11:12 +09:00
Dmitry Osipenko
30af44fae8 PM / devfreq: tegra: Don't ignore clk errors
The clk_set_min_rate() could fail and in this case clk_set_rate() sets
rate to 0, which may drop EMC rate to minimum and make machine very
difficult to use.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-24 20:11:12 +09:00
Dmitry Osipenko
ed2a8dd22a PM / devfreq: tegra: Replace write memory barrier with the read barrier
The write memory barrier isn't needed because the BUS buffer is flushed
by read after write that happens after the removed wmb(), we will also
use readl() instead of the relaxed version to ensure that read is indeed
completed.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-24 20:11:12 +09:00
Dmitry Osipenko
efe9043db4 PM / devfreq: tegra: Replace readl-writel with relaxed versions
There is no need to insert memory barrier on each readl/writel
invocation, hence use the relaxed versions.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-24 20:11:12 +09:00
Dmitry Osipenko
62bacb06b9 PM / devfreq: tegra: Fix kHz to Hz conversion
The kHz to Hz is incorrectly converted in a few places in the code,
this results in a wrong frequency being calculated because devfreq core
uses OPP frequencies that are given in Hz to clamp the rate, while
tegra-devfreq gives to the core value in kHz and then it also expects to
receive value in kHz from the core. In a result memory freq is always set
to a value which is close to ULONG_MAX because of the bug. Hence the EMC
frequency is always capped to the maximum and the driver doesn't do
anything useful. This patch was tested on Tegra30 and Tegra124 SoC's, EMC
frequency scaling works properly now.

Cc: <stable@vger.kernel.org> # 4.14+
Tested-by: Steev Klimaszewski <steev@kali.org>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2019-08-24 20:11:12 +09:00