cpufreq: armada-37xx: Fix driver cleanup when registration failed

[ Upstream commit 92963903a8e11b9576eb7249f8e81eefa93b6f96 ]

Commit 8db82563451f ("cpufreq: armada-37xx: fix freque

cpufreq: armada-37xx: Fix driver cleanup when registration failed

[ Upstream commit 92963903a8e11b9576eb7249f8e81eefa93b6f96 ]

Commit 8db82563451f ("cpufreq: armada-37xx: fix frequency calculation for
opp") changed calculation of frequency passed to the dev_pm_opp_add()
function call. But the code for dev_pm_opp_remove() function call was not
updated, so the driver cleanup phase does not work when registration fails.

This fixes the issue by using the same frequency in both calls.

Signed-off-by: Pali Rohár <pali@kernel.org>
Acked-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Tested-by: Tomasz Maciej Nowak <tmn505@gmail.com>
Tested-by: Anders Trier Olesen <anders.trier.olesen@gmail.com>
Tested-by: Philip Soares <philips@netisense.com>
Fixes: 8db82563451f ("cpufreq: armada-37xx: fix frequency calculation for opp")
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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cpufreq: armada-37xx: Fix the AVS value for load L1

[ Upstream commit d118ac2062b5b8331c8768ac81e016617e0996ee ]

The original CPU voltage value for load L1 is too low for Armada 37x

cpufreq: armada-37xx: Fix the AVS value for load L1

[ Upstream commit d118ac2062b5b8331c8768ac81e016617e0996ee ]

The original CPU voltage value for load L1 is too low for Armada 37xx SoC
when base CPU frequency is 1000 or 1200 MHz. It leads to instabilities
where CPU gets stuck soon after dynamic voltage scaling from load L1 to L0.

Update the CPU voltage value for load L1 accordingly when base frequency is
1000 or 1200 MHz. The minimal L1 value for base CPU frequency 1000 MHz is
updated from the original 1.05V to 1.108V and for 1200 MHz is updated to
1.155V. This minimal L1 value is used only in the case when it is lower
than value for L0.

This change fixes CPU instability issues on 1 GHz and 1.2 GHz variants of
Espressobin and 1 GHz Turris Mox.

Marvell previously for 1 GHz variant of Espressobin provided a patch [1]
suitable only for their Marvell Linux kernel 4.4 fork which workarounded
this issue. Patch forced CPU voltage value to 1.108V in all loads. But
such change does not fix CPU instability issues on 1.2 GHz variants of
Armada 3720 SoC.

During testing we come to the conclusion that using 1.108V as minimal
value for L1 load makes 1 GHz variants of Espressobin and Turris Mox boards
stable. And similarly 1.155V for 1.2 GHz variant of Espressobin.

These two values 1.108V and 1.155V are documented in Armada 3700 Hardware
Specifications as typical initial CPU voltage values.

Discussion about this issue is also at the Armbian forum [2].

[1] - https://github.com/MarvellEmbeddedProcessors/linux-marvell/commit/dc33b62c90696afb6adc7dbcc4ebbd48bedec269
[2] - https://forum.armbian.com/topic/10429-how-to-make-espressobin-v7-stable/

Signed-off-by: Pali Rohár <pali@kernel.org>
Acked-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Tested-by: Tomasz Maciej Nowak <tmn505@gmail.com>
Tested-by: Anders Trier Olesen <anders.trier.olesen@gmail.com>
Tested-by: Philip Soares <philips@netisense.com>
Fixes: 1c3528232f4b ("cpufreq: armada-37xx: Add AVS support")
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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cpufreq: armada-37xx: Fix setting TBG parent for load levels

[ Upstream commit 22592df194e31baf371906cc720da38fa0ab68f5 ]

With CPU frequency determining software [1] we have discove

cpufreq: armada-37xx: Fix setting TBG parent for load levels

[ Upstream commit 22592df194e31baf371906cc720da38fa0ab68f5 ]

With CPU frequency determining software [1] we have discovered that
after this driver does one CPU frequency change, the base frequency of
the CPU is set to the frequency of TBG-A-P clock, instead of the TBG
that is parent to the CPU.

This can be reproduced on EspressoBIN and Turris MOX:
cd /sys/devices/system/cpu/cpufreq/policy0
echo powersave >scaling_governor
echo performance >scaling_governor

Running the mhz tool before this driver is loaded reports 1000 MHz, and
after loading the driver and executing commands above the tool reports
800 MHz.

The change of TBG clock selector is supposed to happen in function
armada37xx_cpufreq_dvfs_setup. Before the function returns, it does
this:
parent = clk_get_parent(clk);
clk_set_parent(clk, parent);

The armada-37xx-periph clock driver has the .set_parent method
implemented correctly for this, so if the method was actually called,
this would work. But since the introduction of the common clock
framework in commit b2476490ef11 ("clk: introduce the common clock..."),
the clk_set_parent function checks whether the parent is actually
changing, and if the requested new parent is same as the old parent
(which is obviously the case for the code above), the .set_parent method
is not called at all.

This patch fixes this issue by filling the correct TBG clock selector
directly in the armada37xx_cpufreq_dvfs_setup during the filling of
other registers at the same address. But the determination of CPU TBG
index cannot be done via the common clock framework, therefore we need
to access the North Bridge Peripheral Clock registers directly in this
driver.

[1] https://github.com/wtarreau/mhz

Signed-off-by: Marek Behún <kabel@kernel.org>
Acked-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Tested-by: Pali Rohár <pali@kernel.org>
Tested-by: Tomasz Maciej Nowak <tmn505@gmail.com>
Tested-by: Anders Trier Olesen <anders.trier.olesen@gmail.com>
Tested-by: Philip Soares <philips@netisense.com>
Fixes: 92ce45fb875d ("cpufreq: Add DVFS support for Armada 37xx")
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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cpufreq: armada-37xx: Add missing MODULE_DEVICE_TABLE

CONFIG_ARM_ARMADA_37XX_CPUFREQ is tristate option and therefore this
cpufreq driver can be compiled as a module. This patch adds mis

cpufreq: armada-37xx: Add missing MODULE_DEVICE_TABLE

CONFIG_ARM_ARMADA_37XX_CPUFREQ is tristate option and therefore this
cpufreq driver can be compiled as a module. This patch adds missing
MODULE_DEVICE_TABLE which generates correct modalias for automatic
loading of this cpufreq driver when is compiled as an external module.

Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Pali Rohár <pali@kernel.org>
Fixes: 92ce45fb875d7 ("cpufreq: Add DVFS support for Armada 37xx")
[ Viresh: Added __maybe_unused ]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

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cpufreq: dt: fix oops on armada37xx

Commit 0c868627e617e43a295d8 (cpufreq: dt: Allow platform specific
intermediate callbacks) added two function pointers to the
struct cpufreq_dt_pl

cpufreq: dt: fix oops on armada37xx

Commit 0c868627e617e43a295d8 (cpufreq: dt: Allow platform specific
intermediate callbacks) added two function pointers to the
struct cpufreq_dt_platform_data. However, armada37xx_cpufreq_driver_init()
has this struct (pdata) located on the stack and uses only "suspend"
and "resume" fields. So these newly added "get_intermediate" and
"target_intermediate" pointers are uninitialized and contain arbitrary
non-null values, causing all kinds of trouble.

For instance, here is an oops on espressobin after an attempt to change
the cpefreq governor:

[ 29.174554] Unable to handle kernel execute from non-executable memory at virtual address ffff00003f87bdc0
...
[ 29.269373] pc : 0xffff00003f87bdc0
[ 29.272957] lr : __cpufreq_driver_target+0x138/0x580
...

Fixed by zeroing out pdata before use.

Cc: <stable@vger.kernel.org> # v5.7+
Signed-off-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

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cpufreq: armada-37xx: Remove set but not used variable 'freq'

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/cpufreq/armada-37xx-cpufreq.c: In function 'armada37xx_cpufreq_a

cpufreq: armada-37xx: Remove set but not used variable 'freq'

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/cpufreq/armada-37xx-cpufreq.c: In function 'armada37xx_cpufreq_avs_setup':
drivers/cpufreq/armada-37xx-cpufreq.c:260:28: warning:
variable 'freq' set but not used [-Wunused-but-set-variable]

It's never used since introduction in commit 1c3528232f4b ("cpufreq:
armada-37xx: Add AVS support")

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

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cpufreq: armada-37xx: fix frequency calculation for opp

The frequency calculation was based on the current(max) frequency of the
CPU. However for low frequency, the value used was alread

cpufreq: armada-37xx: fix frequency calculation for opp

The frequency calculation was based on the current(max) frequency of the
CPU. However for low frequency, the value used was already the parent
frequency divided by a factor of 2.

Instead of using this frequency, this fix directly get the frequency from
the parent clock.

Fixes: 92ce45fb875d ("cpufreq: Add DVFS support for Armada 37xx")
Cc: <stable@vger.kernel.org>
Reported-by: Christian Neubert <christian.neubert.86@gmail.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

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cpufreq: armada-37xx: Add AVS support

Armada 37xx supports Adaptive Voltage Scaling and thanks to this patch a
voltage is associated to each load level.

Signed-off-by: Gregory C

cpufreq: armada-37xx: Add AVS support

Armada 37xx supports Adaptive Voltage Scaling and thanks to this patch a
voltage is associated to each load level.

Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

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cpufreq: add suspend/resume support in Armada 37xx DVFS driver

Add suspend/resume hooks in Armada 37xx DVFS driver to handle S2RAM
operations. As there is currently no 'driver' structure

cpufreq: add suspend/resume support in Armada 37xx DVFS driver

Add suspend/resume hooks in Armada 37xx DVFS driver to handle S2RAM
operations. As there is currently no 'driver' structure, create one
to store both the regmap and the register values during suspend
operation.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

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cpufreq: armada: Free resources on error paths

The resources weren't freed on failures, free them properly.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Miqu

cpufreq: armada: Free resources on error paths

The resources weren't freed on failures, free them properly.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

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cpufreq: armada-37xx: Fix clock leak

There was no clk_put() balancing the clk_get(). This commit fixes it.

Fixes: 92ce45fb875d (cpufreq: Add DVFS support for Armada 37xx)
Cc: 4.

cpufreq: armada-37xx: Fix clock leak

There was no clk_put() balancing the clk_get(). This commit fixes it.

Fixes: 92ce45fb875d (cpufreq: Add DVFS support for Armada 37xx)
Cc: 4.16+ <stable@vger.kernel.org> # 4.16+
Reported-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

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cpufreq: Add DVFS support for Armada 37xx

This patch adds DVFS support for the Armada 37xx SoCs

There are up to four CPU frequency loads for Armada 37xx controlled by
the hardwa

cpufreq: Add DVFS support for Armada 37xx

This patch adds DVFS support for the Armada 37xx SoCs

There are up to four CPU frequency loads for Armada 37xx controlled by
the hardware.

This driver associates the CPU load level to a frequency, then the
hardware will switch while selecting a load level.

The hardware also can associate a voltage for each level (AVS support)
but it is not yet supported

Tested-by: Andre Heider <a.heider@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

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