Commit Graph

3199 Commits

Author SHA1 Message Date
Rafael J. Wysocki
5a5adb1528 cpufreq arm fixes for 5.19-rc6
- mediatek: Handle sram regulator probe deferral
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Merge tag 'cpufreq-arm-fixes-5.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm

Pull a cpufreq ARM fix for 5.19-rc7 from Viresh Kumar:

- mediatek: Handle sram regulator probe deferral

* tag 'cpufreq-arm-fixes-5.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm:
  cpufreq: mediatek: Handle sram regulator probe deferral
2022-07-15 13:54:14 +02:00
AngeloGioacchino Del Regno
d2394860b4 cpufreq: mediatek: Handle sram regulator probe deferral
If the regulator_get_optional() call for the SRAM regulator returns
a probe deferral, we must bail out and retry probing later: failing
to do this will produce unstabilities on platforms requiring the
handling for this regulator.

Fixes: ffa7bdf7f3 ("cpufreq: mediatek: Make sram regulator optional")
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-07-13 16:51:32 +05:30
Rafael J. Wysocki
049b1ed9be cpufreq arm fixes for 5.19-rc5
- Fix missing of_node_put for qoriq and pmac32 driver (Liang He).
 - Fix issues around throttle interrupt for qcom driver (Stephen Boyd).
 - Add MT8186 to cpufreq-dt-platdev blocklist (AngeloGioacchino Del Regno).
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Merge tag 'cpufreq-arm-fixes-5.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm

Pull cpufreq ARM fixes for 5.19-rc5 from Viresh Kumar:

 - Fix missing of_node_put for qoriq and pmac32 driver (Liang He).
 - Fix issues around throttle interrupt for qcom driver (Stephen Boyd).
 - Add MT8186 to cpufreq-dt-platdev blocklist (AngeloGioacchino Del Regno).

* tag 'cpufreq-arm-fixes-5.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm:
  cpufreq: Add MT8186 to cpufreq-dt-platdev blocklist
  cpufreq: pmac32-cpufreq: Fix refcount leak bug
  cpufreq: qcom-hw: Don't do lmh things without a throttle interrupt
  drivers: cpufreq: Add missing of_node_put() in qoriq-cpufreq.c
2022-06-28 17:56:57 +02:00
AngeloGioacchino Del Regno
be4b61ec45 cpufreq: Add MT8186 to cpufreq-dt-platdev blocklist
This SoC shall use the mediatek-cpufreq driver, or the system will
crash upon any clock scaling request: add it to the cpufreq-dt-platdev
blocklist.

Fixes: 39b360102f ("cpufreq: mediatek: Add support for MT8186")
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-06-28 13:34:56 +05:30
Liang He
ccd7567d4b cpufreq: pmac32-cpufreq: Fix refcount leak bug
In pmac_cpufreq_init_MacRISC3(), we need to add corresponding
of_node_put() for the three node pointers whose refcount have
been incremented by of_find_node_by_name().

Signed-off-by: Liang He <windhl@126.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-06-28 13:34:51 +05:30
Stephen Boyd
668a7a12de cpufreq: qcom-hw: Don't do lmh things without a throttle interrupt
Offlining cpu6 and cpu7 and then onlining cpu6 hangs on
sc7180-trogdor-lazor because the throttle interrupt doesn't exist.
Similarly, things go sideways when suspend/resume runs. That's because
the qcom_cpufreq_hw_cpu_online() and qcom_cpufreq_hw_lmh_exit()
functions are calling genirq APIs with an interrupt value of '-6', i.e.
-ENXIO, and that isn't good.

Check the value of the throttle interrupt like we already do in other
functions in this file and bail out early from lmh code to fix the hang.

Reported-by: Rob Clark <robdclark@chromium.org>
Cc: Vladimir Zapolskiy <vladimir.zapolskiy@linaro.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Fixes: a1eb080a04 ("cpufreq: qcom-hw: provide online/offline operations")
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Vladimir Zapolskiy <vladimir.zapolskiy@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-06-28 13:34:51 +05:30
Liang He
4ff5a9b6d9 drivers: cpufreq: Add missing of_node_put() in qoriq-cpufreq.c
In qoriq_cpufreq_probe(), of_find_matching_node() will return a
node pointer with refcount incremented. We should use of_node_put()
when it is not used anymore.

Fixes: 157f527639 ("cpufreq: qoriq: convert to a platform driver")
[ Viresh: Fixed Author's name in commit log ]
Signed-off-by: Liang He <windhl@126.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-06-28 13:34:45 +05:30
Jinzhou Su
b376471fb4 cpufreq: amd-pstate: Add resume and suspend callbacks
When system resumes from S3, the CPPC enable register will be
cleared and reset to 0.

So enable the CPPC interface by writing 1 to this register on
system resume and disable it during system suspend.

Signed-off-by: Jinzhou Su <Jinzhou.Su@amd.com>
Signed-off-by: Jinzhou Su <Jinzhou.Su@amd.com>
Acked-by: Huang Rui <ray.huang@amd.com>
[ rjw: Subject and changelog edits ]
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-06-23 21:19:52 +02:00
Linus Torvalds
96479c0980 ARM: multiplatform changes, part 2
The second part of the multiplatform changes now converts the
 Intel/Marvell PXA platform along with the rest. The patches went through
 several rebases before the merge window as bugs were found, so they
 remained separate.
 
 This has to touch a lot of drivers, in particular the touchscreen,
 pcmcia, sound and clk bits, to detach the driver files from the
 platform and board specific header files.
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Merge tag 'arm-multiplatform-5.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc

Pull more ARM multiplatform updates from Arnd Bergmann:
 "The second part of the multiplatform changes now converts the
  Intel/Marvell PXA platform along with the rest. The patches went
  through several rebases before the merge window as bugs were found, so
  they remained separate.

  This has to touch a lot of drivers, in particular the touchscreen,
  pcmcia, sound and clk bits, to detach the driver files from the
  platform and board specific header files"

* tag 'arm-multiplatform-5.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (48 commits)
  ARM: pxa/mmp: remove traces of plat-pxa
  ARM: pxa: convert to multiplatform
  ARM: pxa/sa1100: move I/O space to PCI_IOBASE
  ARM: pxa: remove support for MTD_XIP
  ARM: pxa: move mach/*.h to mach-pxa/
  ARM: PXA: fix multi-cpu build of xsc3
  ARM: pxa: move plat-pxa to drivers/soc/
  ARM: mmp: rename pxa_register_device
  ARM: mmp: remove tavorevb board support
  ARM: pxa: remove unused mach/bitfield.h
  ARM: pxa: move clk register definitions to driver
  ARM: pxa: move smemc register access from clk to platform
  cpufreq: pxa3: move clk register access to clk driver
  ARM: pxa: remove get_clk_frequency_khz()
  ARM: pxa: pcmcia: move smemc configuration back to arch
  ASoC: pxa: i2s: use normal MMIO accessors
  ASoC: pxa: ac97: use normal MMIO accessors
  ASoC: pxa: use pdev resource for FIFO regs
  Input: wm97xx - get rid of irq_enable method in wm97xx_mach_ops
  Input: wm97xx - switch to using threaded IRQ
  ...
2022-06-02 15:23:54 -07:00
Pierre Gondois
da4363457f cpufreq: CPPC: Fix unused-function warning
Building the cppc_cpufreq driver with for arm64 with
CONFIG_ENERGY_MODEL=n triggers the following warnings:
 drivers/cpufreq/cppc_cpufreq.c:550:12: error: ‘cppc_get_cpu_cost’ defined but not used
[-Werror=unused-function]
   550 | static int cppc_get_cpu_cost(struct device *cpu_dev, unsigned long KHz,
       |            ^~~~~~~~~~~~~~~~~
 drivers/cpufreq/cppc_cpufreq.c:481:12: error: ‘cppc_get_cpu_power’ defined but not used
[-Werror=unused-function]
   481 | static int cppc_get_cpu_power(struct device *cpu_dev,
       |            ^~~~~~~~~~~~~~~~~~

Move the Energy Model related functions into specific guards.
This allows to fix the warning and prevent doing extra work
when the Energy Model is not present.

Fixes: 740fcdc2c2 ("cpufreq: CPPC: Register EM based on efficiency class information")
Reported-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
Tested-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-05-30 15:33:42 +02:00
Zheng Bin
a3f083e04a cpufreq: CPPC: Fix build error without CONFIG_ACPI_CPPC_CPUFREQ_FIE
If CONFIG_ACPI_CPPC_CPUFREQ_FIE is not set, building fails:

drivers/cpufreq/cppc_cpufreq.c: In function ‘populate_efficiency_class’:
drivers/cpufreq/cppc_cpufreq.c:584:2: error: ‘cppc_cpufreq_driver’ undeclared (first use in this function); did you mean ‘cpufreq_driver’?
  cppc_cpufreq_driver.register_em = cppc_cpufreq_register_em;
  ^~~~~~~~~~~~~~~~~~~
  cpufreq_driver

Make declare of cppc_cpufreq_driver out of CONFIG_ACPI_CPPC_CPUFREQ_FIE
to fix this.

Fixes: 740fcdc2c2 ("cpufreq: CPPC: Register EM based on efficiency class information")
Signed-off-by: Zheng Bin <zhengbin13@huawei.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-05-30 15:31:28 +02:00
Rafael J. Wysocki
990247af7c cpufreq arm updates for 5.19-rc1
- Tegra234 cpufreq support (Sumit Gupta).
 
 - Mediatek cleanups and enhancements (Wan Jiabing, Rex-BC Chen, and
   Jia-Wei Chang).
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Merge tag 'cpufreq-arm-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm

Pull ARM cpufreq updates for 5.19-rc1 from Viresh Kumar:

 - Tegra234 cpufreq support (Sumit Gupta).

 - Mediatek cleanups and enhancements (Wan Jiabing, Rex-BC Chen, and
   Jia-Wei Chang).

* tag 'cpufreq-arm-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm: (21 commits)
  cpufreq: mediatek: Add support for MT8186
  cpufreq: mediatek: Link CCI device to CPU
  dt-bindings: cpufreq: mediatek: Add MediaTek CCI property
  cpufreq: mediatek: Fix potential deadlock problem in mtk_cpufreq_set_target
  cpufreq: mediatek: Add opp notification support
  cpufreq: mediatek: Refine mtk_cpufreq_voltage_tracking()
  cpufreq: mediatek: Move voltage limits to platform data
  cpufreq: mediatek: Unregister platform device on exit
  cpufreq: mediatek: Fix NULL pointer dereference in mediatek-cpufreq
  cpufreq: mediatek: Make sram regulator optional
  cpufreq: mediatek: Record previous target vproc value
  cpufreq: mediatek: Replace old_* with pre_*
  cpufreq: mediatek: Use device print to show logs
  cpufreq: mediatek: Enable clocks and regulators
  cpufreq: mediatek: Remove unused headers
  cpufreq: mediatek: Cleanup variables and error handling in mtk_cpu_dvfs_info_init()
  cpufreq: mediatek: Use module_init and add module_exit
  arm64: tegra: add node for tegra234 cpufreq
  cpufreq: tegra194: Add support for Tegra234
  cpufreq: tegra194: add soc data to support multiple soc
  ...
2022-05-25 15:01:30 +02:00
Pierre Gondois
2d41dc2380 cpufreq: CPPC: Enable dvfs_possible_from_any_cpu
The communication mean of the _CPC desired performance can be
PCC, System Memory, System IO, or Functional Fixed Hardware (FFH).

PCC, SystemMemory and SystemIo address spaces are available from any
CPU. Thus, dvfs_possible_from_any_cpu should be enabled in such case.
For FFH, let the FFH implementation do smp_call_function_*() calls.

Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-05-19 19:45:34 +02:00
Pierre Gondois
3cc30dd00a cpufreq: CPPC: Enable fast_switch
The communication mean of the _CPC desired performance can be
PCC, System Memory, System IO, or Functional Fixed Hardware.

commit b7898fda5b ("cpufreq: Support for fast frequency switching")
fast_switching is 'for switching CPU frequencies from interrupt
context'.
Writes to SystemMemory and SystemIo are fast and suitable this.
This is not the case for PCC and might not be the case for FFH.

Enable fast_switching for the cppc_cpufreq driver in above cases.

Add cppc_allow_fast_switch() to check the desired performance
register address space and set fast_switching accordingly.

Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-05-19 19:45:34 +02:00
Schspa Shi
514ff1bcd9 cpufreq: make interface functions and lock holding state clear
cpufreq_offline() calls offline() and exit() under the policy rwsem
But they are called outside the rwsem in cpufreq_online().

Make cpufreq_online() call offline() and exit() as well as online() and
init() under the policy rwsem to achieve a clear lock relationship.

All of the init() and online() implementations in the tree only
initialize the policy object without attempting to acquire the policy
rwsem and they won't call cpufreq APIs attempting to acquire it.

Signed-off-by: Schspa Shi <schspa@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
[ rjw: Changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-05-17 21:39:05 +02:00
Schspa Shi
d4627a287e cpufreq: Abort show()/store() for half-initialized policies
If policy initialization fails after the sysfs files are created,
there is a possibility to end up running show()/store() callbacks
for half-initialized policies, which may have unpredictable
outcomes.

Abort show()/store() in such a case by making sure the policy is active.

Also dectivate the policy on such failures.

Signed-off-by: Schspa Shi <schspa@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-05-17 21:39:04 +02:00
Rafael J. Wysocki
f339f35417 cpufreq: Rearrange locking in cpufreq_remove_dev()
Currently, cpufreq_remove_dev() invokes the ->exit() driver callback
without holding the policy rwsem which is inconsistent with what
happens if ->exit() is invoked directly from cpufreq_offline().

It also manipulates the real_cpus mask and removes the CPU device
symlink without holding the policy rwsem, but cpufreq_offline() holds
the rwsem around the modifications thereof.

For consistency, modify cpufreq_remove_dev() to hold the policy rwsem
until the ->exit() callback has been called (or it has been determined
that it is not necessary to call it).

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-05-12 17:11:57 +02:00
Rafael J. Wysocki
fddd8f86df cpufreq: Split cpufreq_offline()
Split the "core" part running under the policy rwsem out of
cpufreq_offline() to allow the locking in cpufreq_remove_dev() to be
rearranged more easily.

As a side-effect this eliminates the unlock label that's not needed
any more.

No expected functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-05-12 17:11:57 +02:00
Rafael J. Wysocki
e1e962c5b9 cpufreq: Reorganize checks in cpufreq_offline()
Notice that cpufreq_offline() only needs to check policy_is_inactive()
once and rearrange the code in there to make that happen.

No expected functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-05-12 17:11:57 +02:00
Jia-Wei Chang
39b360102f cpufreq: mediatek: Add support for MT8186
The platform data of MT8186 is different from previous MediaTek SoCs,
so we add a new compatible and platform data for it.

Signed-off-by: Jia-Wei Chang <jia-wei.chang@mediatek.com>
Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-05-12 10:39:31 +05:30
Rex-BC Chen
0daa47325b cpufreq: mediatek: Link CCI device to CPU
In some MediaTek SoCs, like MT8183, CPU and CCI share the same power
supplies. Cpufreq needs to check if CCI devfreq exists and wait until
CCI devfreq ready before scaling frequency.

Before CCI devfreq is ready, we record the voltage when booting to
kernel and use the max(cpu target voltage, booting voltage) to
prevent cpufreq adjust to the lower voltage which will cause the CCI
crash because of high frequency and low voltage.

- Add is_ccifreq_ready() to link CCI device to CPI, and CPU will start
  DVFS when CCI is ready.
- Add platform data for MT8183.

Signed-off-by: Jia-Wei Chang <jia-wei.chang@mediatek.com>
Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-05-12 10:39:31 +05:30
Viresh Kumar
5c84c1b84b cpufreq: Clear real_cpus mask from remove_cpu_dev_symlink()
add_cpu_dev_symlink() is responsible for setting the CPUs in the
real_cpus mask, the reverse of which should be done from
remove_cpu_dev_symlink() to make it look clean and avoid any breakage
later on.

Move the call to clear the mask to remove_cpu_dev_symlink().

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-05-11 19:23:10 +02:00
Srinivas Pandruvada
bbd67f1b5a cpufreq: intel_pstate: Support Sapphire Rapids OOB mode
Prevent intel_pstate to load when OOB (Out Of Band) P-states mode is
enabled in Sapphire Rapids. The OOB identifying bits are same as the
prior generation CPUs like Ice Lake servers. So, also add Sapphire
Rapids to intel_pstate_cpu_oob_ids list.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-05-11 19:17:43 +02:00
Wan Jiabing
85f5b3c437 cpufreq: mediatek: Fix potential deadlock problem in mtk_cpufreq_set_target
Fix following coccichek error:
./drivers/cpufreq/mediatek-cpufreq.c:199:2-8: preceding lock on line
./drivers/cpufreq/mediatek-cpufreq.c:208:2-8: preceding lock on line

mutex_lock is acquired but not released before return.
Use 'goto out' to help releasing the mutex_lock.

Fixes: c210063b40 ("cpufreq: mediatek: Add opp notification support")
Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Reviewed-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-05-10 14:40:56 +05:30
Viresh Kumar
85f0e42bd6 Revert "cpufreq: Fix possible race in cpufreq online error path"
This reverts commit f346e96267.

The commit tried to fix a possible real bug but it made it even worse.
The fix was simply buggy as now an error out to out_offline_policy or
out_exit_policy will try to release a semaphore which was never taken in
the first place. This works fine only if we failed late, i.e. via
out_destroy_policy.

Fixes: f346e96267 ("cpufreq: Fix possible race in cpufreq online error path")
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-05-09 18:51:54 +02:00
Arnd Bergmann
5c6603e741 cpufreq: pxa3: move clk register access to clk driver
The driver needs some low-level register access for setting
the core and bus frequencies. These registers are owned
by the clk driver, so move the low-level access into that
driver with a slightly higher-level interface and avoid
any machine header file dependencies.

Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Stephen Boyd <sboyd@kernel.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: linux-clk@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2022-05-07 22:55:49 +02:00
Arnd Bergmann
e0a3596eb8 ARM: pxa: remove get_clk_frequency_khz()
get_clk_frequency_khz() is not a proper name for a global function,
and there is only one caller.

Convert viper to use the properly namespaced
pxa25x_get_clk_frequency_khz() and remove the other references.

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Cc: linux-pm@vger.kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2022-05-07 22:55:49 +02:00
Pierre Gondois
740fcdc2c2 cpufreq: CPPC: Register EM based on efficiency class information
Performance states and energy consumption values are not advertised
in ACPI. In the GicC structure of the MADT table, the "Processor
Power Efficiency Class field" (called efficiency class from now)
allows to describe the relative energy efficiency of CPUs.

To leverage the EM and EAS, the CPPC driver creates a set of
artificial performance states and registers them in the Energy Model
(EM), such as:
- Every 20 capacity unit, a performance state is created.
- The energy cost of each performance state gradually increases.
No power value is generated as only the cost is used in the EM.

During task placement, a task can raise the frequency of its whole
pd. This can make EAS place a task on a pd with CPUs that are
individually less energy efficient.
As cost values are artificial, and to place tasks on CPUs with the
lower efficiency class, a gap in cost values is generated for adjacent
efficiency classes.
E.g.:
- efficiency class = 0, capacity is in [0-1024], so cost values
  are in [0: 51] (one performance state every 20 capacity unit)
- efficiency class = 1, capacity is in [0-1024], cost values
  are in [1*gap+0: 1*gap+51].

The value of the cost gap is chosen to absorb a the energy of 4 CPUs
at their maximum capacity. This means that between:
1- a pd of 4 CPUs, each of them being used at almost their full
   capacity. Their efficiency class is N.
2- a CPU using almost none of its capacity. Its efficiency class is
   N+1
EAS will choose the first option.

This patch also populates the (struct cpufreq_driver).register_em
callback if the valid efficiency_class ACPI values are provided.

Signed-off-by: Pierre Gondois <Pierre.Gondois@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-05-06 21:01:17 +02:00
Pierre Gondois
d3c3db41df cpufreq: CPPC: Add per_cpu efficiency_class
In ACPI, describing power efficiency of CPUs can be done through the
following arm specific field:
ACPI 6.4, s5.2.12.14 'GIC CPU Interface (GICC) Structure',
'Processor Power Efficiency Class field':
  Describes the relative power efficiency of the associated pro-
  cessor. Lower efficiency class numbers are more efficient than
  higher ones (e.g. efficiency class 0 should be treated as more
  efficient than efficiency class 1). However, absolute values
  of this number have no meaning: 2 isn’t necessarily half as
  efficient as 1.

The efficiency_class field is stored in the GicC structure of the
ACPI MADT table and it's currently supported in Linux for arm64 only.
Thus, this new functionality is introduced for arm64 only.

To allow the cppc_cpufreq driver to know and preprocess the
efficiency_class values of all the CPUs, add a per_cpu efficiency_class
variable to store them.

At least 2 different efficiency classes must be present,
otherwise there is no use in creating an Energy Model.

The efficiency_class values are squeezed in [0:#efficiency_class-1]
while conserving the order. For instance, efficiency classes of:
  [111, 212, 250]
will be mapped to:
  [0 (was 111), 1 (was 212), 2 (was 250)].

Each policy being independently registered in the driver, populating
the per_cpu efficiency_class is done only once at the driver
initialization. This prevents from having each policy re-searching the
efficiency_class values of other CPUs. The EM will be registered in a
following patch.

The patch also exports acpi_cpu_get_madt_gicc() to fetch the GicC
structure of the ACPI MADT table for each CPU.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Pierre Gondois <Pierre.Gondois@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-05-06 21:01:17 +02:00
Rafael J. Wysocki
46acb9d9b6 Merge Energy Model material for 5.19 to satisfy dependencies. 2022-05-06 21:00:44 +02:00
Viresh Kumar
f55ae08c89 cpufreq: Avoid unnecessary frequency updates due to mismatch
For some platforms, the frequency returned by hardware may be slightly
different from what is provided in the frequency table. For example,
hardware may return 499 MHz instead of 500 MHz. In such cases it is
better to avoid getting into unnecessary frequency updates, as we may
end up switching policy->cur between the two and sending unnecessary
pre/post update notifications, etc.

This patch has chosen allows the hardware frequency and table frequency
to deviate by 1 MHz for now, we may want to increase it a bit later on
if someone still complains.

Reported-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Jia-wei Chang <jia-wei.chang@mediatek.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-05-06 20:56:21 +02:00
Rex-BC Chen
c210063b40 cpufreq: mediatek: Add opp notification support
From this opp notifier, cpufreq should listen to opp notification and do
proper actions when receiving events of disable and voltage adjustment.

One of the user for this opp notifier is MediaTek SVS.
The MediaTek Smart Voltage Scaling (SVS) is a hardware which calculates
suitable SVS bank voltages to OPP voltage table.

Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com>
Signed-off-by: Jia-Wei Chang <jia-wei.chang@mediatek.com>
Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
[ Viresh: Renamed opp_freq as current_freq and moved its initialization ]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-05-06 09:43:42 +05:30
Jia-Wei Chang
6a17b3876b cpufreq: mediatek: Refine mtk_cpufreq_voltage_tracking()
Because the difference of sram and proc should in a range of min_volt_shift
and max_volt_shift. We need to adjust the sram and proc step by step.

We replace VOLT_TOL (voltage tolerance) with the platform data and update the
logic to determine the voltage boundary and invoking regulator_set_voltage.

- Use 'sram_min_volt' and 'sram_max_volt' to determine the voltage boundary
  of sram regulator.
- Use (sram_min_volt - min_volt_shift) and 'proc_max_volt' to determine the
  voltage boundary of vproc regulator.

Moreover, to prevent infinite loop when tracking voltage, we calculate the
maximum value for each platform data.
We assume min voltage is 0 and tracking target voltage using
min_volt_shift for each iteration.
The retry_max is 3 times of expeted iteration count.

Signed-off-by: Jia-Wei Chang <jia-wei.chang@mediatek.com>
Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-05-06 09:40:42 +05:30
Rex-BC Chen
ead858bd12 cpufreq: mediatek: Move voltage limits to platform data
Voltages and shifts are defined as macros originally.
There are different requirements of these values for each MediaTek SoCs.
Therefore, we add the platform data and move these values into it.

Signed-off-by: Jia-Wei Chang <jia-wei.chang@mediatek.com>
Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-05-06 09:40:02 +05:30
Rex-BC Chen
f126fbadce cpufreq: mediatek: Unregister platform device on exit
We register the platform device when driver inits. However, we do not
unregister it when driver exits.

To resolve this, we declare the platform data to be a global static
variable and rename it to be "cpufreq_pdev". With this global variable,
we can do platform_device_unregister() when driver exits.

Fixes: 501c574f4e ("cpufreq: mediatek: Add support of cpufreq to MT2701/MT7623 SoC")
Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
[ Viresh: Commit log and Subject ]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-05-06 09:38:10 +05:30
Rafael J. Wysocki
02678c0882 Merge back earlier cpufreq changes for 5.19. 2022-05-05 14:22:23 +02:00
Wan Jiabing
a3b8d1b12c cpufreq: mediatek: Fix NULL pointer dereference in mediatek-cpufreq
Fix following coccicheck error:
drivers/cpufreq/mediatek-cpufreq.c:464:16-23: ERROR: info is NULL but dereferenced.

Use pr_err instead of dev_err to avoid dereferring a NULL pointer.

Fixes: f52b16ba9fe4 ("cpufreq: mediatek: Use device print to show logs")
Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-04-27 08:51:14 +05:30
Jia-Wei Chang
ffa7bdf7f3 cpufreq: mediatek: Make sram regulator optional
For some MediaTek SoCs, like MT8186, it's possible that the sram regulator
is shared between CPU and CCI.
We hope regulator framework can return error for error handling rather
than a dummy handler from regulator_get api.
Therefore, we choose to use regulator_get_optional.

Signed-off-by: Jia-Wei Chang <jia-wei.chang@mediatek.com>
Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-04-26 12:09:10 +05:30
Jia-Wei Chang
bffcd33313 cpufreq: mediatek: Record previous target vproc value
We found the buck voltage may not be exactly the same with what we set
because CPU may share the same buck with other module.
Therefore, we need to record the previous desired value instead of reading
it from regulators.

Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com>
Signed-off-by: Jia-Wei Chang <jia-wei.chang@mediatek.com>
Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-04-26 12:09:10 +05:30
Rex-BC Chen
4aef4aeaf1 cpufreq: mediatek: Replace old_* with pre_*
To make driver more readable, replace old_* with pre_*.

Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-04-26 12:09:10 +05:30
Rex-BC Chen
9acc0f7a6e cpufreq: mediatek: Use device print to show logs
- Replace pr_* with dev_* to show logs.
- Remove usage of __func__.

Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-04-26 12:09:10 +05:30
Jia-Wei Chang
4b9ceb757b cpufreq: mediatek: Enable clocks and regulators
We need to enable regulators so that the max and min requested values will
be recorded.
The intermediate clock is not always enabled by CCF in different projects,
so we should enable it in the cpufreq driver.

Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com>
Signed-off-by: Jia-Wei Chang <jia-wei.chang@mediatek.com>
Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-04-26 12:09:10 +05:30
Jia-Wei Chang
ad97585781 cpufreq: mediatek: Remove unused headers
Remove unused headers.

Signed-off-by: Jia-Wei Chang <jia-wei.chang@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-04-26 12:09:10 +05:30
Jia-Wei Chang
396dee972a cpufreq: mediatek: Cleanup variables and error handling in mtk_cpu_dvfs_info_init()
- Remove several unnecessary varaibles in mtk_cpu_dvfs_info_init().
- Unify error message format and use dev_err_probe() if possible.

Signed-off-by: Jia-Wei Chang <jia-wei.chang@mediatek.com>
Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-04-26 12:09:10 +05:30
Jia-Wei Chang
b7070187c8 cpufreq: mediatek: Use module_init and add module_exit
- Use module_init instead of device_initcall.
- Add a function for module_exit to unregister driver.

Signed-off-by: Jia-Wei Chang <jia-wei.chang@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-04-26 12:09:09 +05:30
Sumit Gupta
273bc890a2 cpufreq: tegra194: Add support for Tegra234
This patch adds driver support for Tegra234 cpufreq.
Tegra234 has per core MMIO registers instead of system registers for
cpu frequency requests and to read the counters for re-constructing
the cpu frequency. Also, MPIDR affinity info in Tegra234 is different
from Tegra194.
Added ops hooks  and soc data for Tegra234. This will help to easily
add variants of Tegra234 and future SoC's which use similar logic to
{get|set} the cpu frequency.

Signed-off-by: Sumit Gupta <sumitg@nvidia.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-04-26 12:09:09 +05:30
Sumit Gupta
0839ed1fd7 cpufreq: tegra194: add soc data to support multiple soc
Adding SoC data and ops to support multiple SoC's in same driver.

Signed-off-by: Sumit Gupta <sumitg@nvidia.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-04-26 12:09:09 +05:30
Vladimir Zapolskiy
e4e6448638 cpufreq: qcom-cpufreq-hw: Clear dcvs interrupts
It's noted that dcvs interrupts are not self-clearing, thus an interrupt
handler runs constantly, which leads to a severe regression in runtime.
To fix the problem an explicit write to clear interrupt register is
required, note that on OSM platforms the register may not be present.

Fixes: 275157b367 ("cpufreq: qcom-cpufreq-hw: Add dcvs interrupt support")
Signed-off-by: Vladimir Zapolskiy <vladimir.zapolskiy@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-04-26 12:08:31 +05:30
Xiaobing Luo
1aa24a8f3b cpufreq: fix memory leak in sun50i_cpufreq_nvmem_probe
--------------------------------------------
unreferenced object 0xffff000010742a00 (size 128):
  comm "swapper/0", pid 1, jiffies 4294902015 (age 1187.652s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<00000000b4dfebaa>] __kmalloc+0x338/0x474
    [<00000000d6e716db>] sun50i_cpufreq_nvmem_probe+0xc4/0x36c
    [<000000007d6082a0>] platform_probe+0x98/0x11c
    [<00000000c990f549>] really_probe+0x234/0x5a0
    [<000000002d9fecc6>] __driver_probe_device+0x194/0x224
    [<00000000cf0b94fa>] driver_probe_device+0x64/0x13c
    [<00000000f238e4cf>] __device_attach_driver+0xf8/0x180
    [<000000006720e418>] bus_for_each_drv+0xf8/0x160
    [<00000000df4f14f6>] __device_attach+0x174/0x29c
    [<00000000782002fb>] device_initial_probe+0x20/0x30
    [<00000000c2681b06>] bus_probe_device+0xfc/0x110
    [<00000000964cf3bd>] device_add+0x5f0/0xcd0
    [<000000004b9264e3>] platform_device_add+0x198/0x390
    [<00000000fa82a9d0>] platform_device_register_full+0x178/0x210
    [<000000009a5daf13>] sun50i_cpufreq_init+0xf8/0x168
    [<000000000377cc7c>] do_one_initcall+0xe4/0x570
--------------------------------------------

if sun50i_cpufreq_get_efuse failed, then opp_tables leak.

Fixes: f328584f7b ("cpufreq: Add sun50i nvmem based CPU scaling driver")
Signed-off-by: Xiaobing Luo <luoxiaobing0926@gmail.com>
Reviewed-by: Samuel Holland <samuel@sholland.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-04-25 10:35:24 +05:30
Schspa Shi
f346e96267 cpufreq: Fix possible race in cpufreq online error path
When cpufreq online fails, the policy->cpus mask is not cleared and
policy->rwsem is released too early, so the driver can be invoked
via the cpuinfo_cur_freq sysfs attribute while its ->offline() or
->exit() callbacks are being run.

Take policy->clk as an example:

static int cpufreq_online(unsigned int cpu)
{
  ...
  // policy->cpus != 0 at this time
  down_write(&policy->rwsem);
  ret = cpufreq_add_dev_interface(policy);
  up_write(&policy->rwsem);

  return 0;

out_destroy_policy:
	for_each_cpu(j, policy->real_cpus)
		remove_cpu_dev_symlink(policy, get_cpu_device(j));
    up_write(&policy->rwsem);
...
out_exit_policy:
  if (cpufreq_driver->exit)
    cpufreq_driver->exit(policy);
      clk_put(policy->clk);
      // policy->clk is a wild pointer
...
                                    ^
                                    |
                            Another process access
                            __cpufreq_get
                              cpufreq_verify_current_freq
                                cpufreq_generic_get
                                  // acces wild pointer of policy->clk;
                                    |
                                    |
out_offline_policy:                 |
  cpufreq_policy_free(policy);      |
    // deleted here, and will wait for no body reference
    cpufreq_policy_put_kobj(policy);
}

Address this by modifying cpufreq_online() to release policy->rwsem
in the error path after the driver callbacks have run and to clear
policy->cpus before releasing the semaphore.

Fixes: 7106e02bae ("cpufreq: release policy->rwsem on error")
Signed-off-by: Schspa Shi <schspa@gmail.com>
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-04-22 18:17:48 +02:00