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2024-03-01powercap: dtpm: Fix kernel-doc for dtpm_create_hierarchy() functionYang Li1-1/+1
The existing comment block above the dtpm_create_hierarchy function does not conform to the kernel-doc standard. This patch fixes the documentation to match the expected kernel-doc format, which includes a structured documentation header with param and return value. Signed-off-by: Yang Li <yang.lee@linux.alibaba.com> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-03-01powercap: DTPM: Fix spelling mistake "initialze" -> "initialize"Colin Ian King1-1/+1
There is a spelling mistake in a pr_info() message. Fix it. Signed-off-by: Colin Ian King <colin.i.king@gmail.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-03-01powercap: DTPM: dtpm_node_callback[] can be statickernel test robot1-1/+1
drivers/powercap/dtpm.c:525:22: warning: symbol 'dtpm_node_callback' was not declared. Should it be static? Fixes: 3759ec678e89 ("powercap/drivers/dtpm: Add hierarchy creation") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: kernel test robot <lkp@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-02-23powercap/dtpm: Move the 'root' reset placeDaniel Lezcano1-3/+2
The 'root' node is checked everytime a dtpm node is destroyed. When we reach the end of the hierarchy destruction function, we can unconditionnaly set the 'root' node to NULL again. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Link: https://lore.kernel.org/r/20220130210210.549877-5-daniel.lezcano@linaro.org
2022-02-23powercap/dtpm: Destroy hierarchy functionDaniel Lezcano1-0/+43
The hierarchy creation function exits but without a destroy hierarchy function. Due to that, the modules creating the hierarchy can not be unloaded properly because they don't have an exit callback. Provide the dtpm_destroy_hierarchy() function to remove the previously created hierarchy. The function relies on all the release mechanisms implemented by the underlying powercap framework. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Link: https://lore.kernel.org/r/20220130210210.549877-4-daniel.lezcano@linaro.org
2022-02-23powercap/dtpm: Fixup kfree for virtual nodeDaniel Lezcano1-2/+2
When the node is virtual there is no release function associated which can free the memory. Free the memory when no 'ops' exists. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/20220130210210.549877-3-daniel.lezcano@linaro.org
2022-02-23powercap/dtpm: Change locking schemeDaniel Lezcano1-68/+27
The different functions are all called through the dtpm_create_hierarchy() which handle the mutex. The different functions are used in this context, consequently with the lock always held. Remove all locks taken in the function and add the lock in the hierarchy creation function. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Link: https://lore.kernel.org/r/20220130210210.549877-1-daniel.lezcano@linaro.org
2022-02-04powercap/drivers/dtpm: Add hierarchy creationDaniel Lezcano1-3/+187
The DTPM framework is available but without a way to configure it. This change provides a way to create a hierarchy of DTPM node where the power consumption reflects the sum of the children's power consumption. It is up to the platform to specify an array of dtpm nodes where each element has a pointer to its parent, except the top most one. The type of the node gives the indication of which initialization callback to call. At this time, we can create a virtual node, where its purpose is to be a parent in the hierarchy, and a DT node where the name describes its path. In order to ensure a nice self-encapsulation, the DTPM subsys array contains a couple of initialization functions, one to setup the DTPM backend and one to initialize it up. With this approach, the DTPM framework has a very few material to export. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Link: https://lore.kernel.org/r/20220128163537.212248-3-daniel.lezcano@linaro.org
2022-02-04powercap/drivers/dtpm: Convert the init table section to a simple arrayDaniel Lezcano1-0/+2
The init table section is freed after the system booted. However the next changes will make per module the DTPM description, so the table won't be accessible when the module is loaded. In order to fix that, we should move the table to the data section where there are very few entries and that makes strange to add it there. The main goal of the table was to keep self-encapsulated code and we can keep it almost as it by using an array instead. Suggested-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/20220128163537.212248-2-daniel.lezcano@linaro.org
2021-12-23powercap/drivers/dtpm: Reduce trace verbosityDaniel Lezcano1-3/+3
The traces when registering a powerzone is at the pr_info level and should be changed to pr_debug as requested by Greg-KH. Cc: Greg KH <gregkh@linuxfoundation.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lkml.kernel.org/r/YGAnRx8SiZHFPpY6@kroah.com Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/20211123101601.2433340-2-daniel.lezcano@linaro.org
2021-12-03powercap: DTPM: Drop unused local variable from init_dtpm()Rafael J. Wysocki1-2/+0
The dtpm_descr variable in init_dtpm() is not used after commit f751db8adaea ("powercap/drivers/dtpm: Disable DTPM at boot time"), so drop it. Fixes: f751db8adaea ("powercap/drivers/dtpm: Disable DTPM at boot time") Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-12-01powercap/drivers/dtpm: Disable DTPM at boot timeDaniel Lezcano1-3/+0
The DTPM framework misses a mechanism to set it up. That is currently under review but will come after the next cycle. As the distro are enabling all the kernel options, the DTPM framework is enabled on platforms where the energy model is not implemented, thus making the framework inconsistent and disrupting the CPU frequency scaling service. Remove the initialization at boot time as a hot fix. Fixes: 7a89d7eacf8e ("powercap/drivers/dtpm: Simplify the dtpm table") Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Reported-By: Doug Smythies <dsmythies@telus.net> Tested-By: Doug Smythies <dsmythies@telus.net> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-10-21powercap/drivers/dtpm: Fix power limit initializationDaniel Lezcano1-1/+3
When a DTPM node is registered its power limit must be initialized to the power max. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/20210318205238.21937-1-daniel.lezcano@linaro.org
2021-10-21powercap/drivers/dtpm: Use container_of instead of a private data fieldDaniel Lezcano1-12/+6
The dtpm framework provides an API to allocate a dtpm node. However when a backend dtpm driver needs to allocate a dtpm node it must define its own structure and store the pointer of this structure in the private field of the dtpm structure. It is more elegant to use the container_of macro and add the dtpm structure inside the dtpm backend specific structure. The code will be able to deal properly with the dtpm structure as a generic entity, making all this even more self-encapsulated. The dtpm_alloc() function does no longer make sense as the dtpm structure will be allocated when allocating the device specific dtpm structure. The dtpm_init() is provided instead. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Reviewed-by: Lukasz Luba <lukasz.luba@arm.com> Link: https://lore.kernel.org/r/20210312130411.29833-4-daniel.lezcano@linaro.org
2021-10-21powercap/drivers/dtpm: Simplify the dtpm tableDaniel Lezcano1-2/+2
The dtpm table is an array of pointers, that forces the user of the table to define initdata along with the declaration of the table entry. It is more efficient to create an array of dtpm structure, so the declaration of the table entry can be done by initializing the different fields. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Reviewed-by: Lukasz Luba <lukasz.luba@arm.com> Link: https://lore.kernel.org/r/20210312130411.29833-3-daniel.lezcano@linaro.org
2021-10-21powercap/drivers/dtpm: Encapsulate even more the codeDaniel Lezcano1-27/+27
In order to increase the self-encapsulation of the dtpm generic code, the following changes are adding a power update ops to the dtpm ops. That allows the generic code to call directly the dtpm backend function to update the power values. The power update function does compute the power characteristics when the function is invoked. In the case of the CPUs, the power consumption depends on the number of online CPUs. The online CPUs mask is not up to date at CPUHP_AP_ONLINE_DYN state in the tear down callback. That is the reason why the online / offline are at separate state. As there is already an existing state for DTPM, this one is only moved to the DEAD state, so there is no addition of new state with these changes. The dtpm node is not removed when the cpu is unplugged. That simplifies the code for the next changes and results in a more self-encapsulated code. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Reviewed-by: Lukasz Luba <lukasz.luba@arm.com> Link: https://lore.kernel.org/r/20210312130411.29833-1-daniel.lezcano@linaro.org
2021-03-01powercap/drivers/dtpm: Fix root node initializationDaniel Lezcano1-0/+3
The root node is not set to NULL when the dtpm root node is removed. Consequently, it is not possible to create a new root as it is already set. Set the root node to NULL when the last node is removed. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-07powercap/drivers/dtpm: Fix an IS_ERR() vs NULL checkDan Carpenter1-2/+2
The powercap_register_control_type() function never returns NULL, it returns error pointers on error so update this check. Fixes: a20d0ef97abf ("powercap/drivers/dtpm: Add API for dynamic thermal power management") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-07powercap/drivers/dtpm: Fix some missing unlock bugsDan Carpenter1-5/+12
We need to unlock on these paths before returning. Fixes: a20d0ef97abf ("powercap/drivers/dtpm: Add API for dynamic thermal power management") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-07powercap/drivers/dtpm: Fix a double shift bugDan Carpenter1-1/+1
The DTPM_POWER_LIMIT_FLAG is used for test_bit() etc which take a bit number so it should be bit 0. But currently it's set to BIT(0) then that is double shifted equivalent to BIT(BIT(0)). This doesn't cause a run time problem because it's done consistently. Fixes: a20d0ef97abf ("powercap/drivers/dtpm: Add API for dynamic thermal power management") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-12-30powercap/drivers/dtpm: Fix __udivdi3 and __aeabi_uldivmod unresolved symbolsDaniel Lezcano1-3/+3
32-bit architectures do not support u64 divisions, so the macro DIV_ROUND_CLOSEST is not adequate as the compiler will replace the call to an unexisting function for the platform, leading to unresolved references to symbols. Fix this by using the compatible macros: DIV64_U64_ROUND_CLOSEST and DIV_ROUND_CLOSEST_ULL. Fixes: a20d0ef97abf ("powercap/drivers/dtpm: Add API for dynamic thermal power management") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-12-22powercap/drivers/dtpm: Add API for dynamic thermal power managementDaniel Lezcano1-0/+473
On the embedded world, the complexity of the SoC leads to an increasing number of hotspots which need to be monitored and mitigated as a whole in order to prevent the temperature to go above the normative and legally stated 'skin temperature'. Another aspect is to sustain the performance for a given power budget, for example virtual reality where the user can feel dizziness if the GPU performance is capped while a big CPU is processing something else. Or reduce the battery charging because the dissipated power is too high compared with the power consumed by other devices. The userspace is the most adequate place to dynamically act on the different devices by limiting their power given an application profile: it has the knowledge of the platform. These userspace daemons are in charge of the Dynamic Thermal Power Management (DTPM). Nowadays, the dtpm daemons are abusing the thermal framework as they act on the cooling device state to force a specific and arbitrary state without taking care of the governor decisions. Given the closed loop of some governors that can confuse the logic or directly enter in a decision conflict. As the number of cooling device support is limited today to the CPU and the GPU, the dtpm daemons have little control on the power dissipation of the system. The out of tree solutions are hacking around here and there in the drivers, in the frameworks to have control on the devices. The common solution is to declare them as cooling devices. There is no unification of the power limitation unit, opaque states are used. This patch provides a way to create a hierarchy of constraints using the powercap framework. The devices which are registered as power limit-able devices are represented in this hierarchy as a tree. They are linked together with intermediate nodes which are just there to propagate the constraint to the children. The leaves of the tree are the real devices, the intermediate nodes are virtual, aggregating the children constraints and power characteristics. Each node have a weight on a 2^10 basis, in order to reflect the percentage of power distribution of the children's node. This percentage is used to dispatch the power limit to the children. The weight is computed against the max power of the siblings. This simple approach allows to do a fair distribution of the power limit. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Reviewed-by: Lukasz Luba <lukasz.luba@arm.com> Tested-by: Lukasz Luba <lukasz.luba@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>