Re: [PATCH v5 0/8] Support for autonomous selection in cppc_cpufreq

["zhenglifeng (A)" <zhenglifeng1@huawei.com>]

On 2025/2/24 18:31, Pierre Gondois wrote:
> 
> 
> On 2/22/25 11:07, zhenglifeng (A) wrote:
>> On 2025/2/19 3:17, Rafael J. Wysocki wrote:
>>> On Thu, Feb 13, 2025 at 2:55 AM zhenglifeng (A) <zhenglifeng1@huawei.com> wrote:
>>>>
>>>> On 2025/2/6 21:14, Lifeng Zheng wrote:
>>>>> Add sysfs interfaces for CPPC autonomous selection in the cppc_cpufreq
>>>>> driver.
>>>>>
>>>>> The patch series is organized in two parts:
>>>>>
>>>>>   - patch 1-5 refactor out the general CPPC register get and set functions
>>>>>     in cppc_acpi.c
>>>>>
>>>>>   - patches 6-8 expose sysfs files for users to control CPPC autonomous
>>>>>     selection when supported
>>>>>
>>>>> Changelog:
>>>>>
>>>>> v5:
>>>>>
>>>>>   - add more explanation to the commit logs and comments
>>>>>   - change REG_OPTIONAL from bin to hex
>>>>>   - split patch 2 into 3 smaller patches
>>>>>   - remove CPPC_REG_VAL_READ() and CPPC_REG_VAL_WRITE() macros
>>>>>   - move the modification part in patch 5 into a separate patch
>>>>>   - rename the sysfs file from "energy_perf" to
>>>>>     energy_performance_preference_val
>>>>>
>>>>> v4:
>>>>>
>>>>>   - add REG_OPTIONAL and IS_OPTIONAL_CPC_REG to judge if a cpc register is
>>>>>     an optional one
>>>>>   - check whether the register is optional before CPC_SUPPORTED check in
>>>>>     cppc_get_reg_val() and cppc_set_reg_val()
>>>>>   - check the register's type in cppc_set_reg_val()
>>>>>   - add macros to generally implement registers getting and setting
>>>>>     functions
>>>>>   - move some logic codes from cppc_cpufreq.c to cppc_acpi.c
>>>>>   - replace cppc_get_auto_sel_caps() by cppc_get_auto_sel()
>>>>>
>>>>> v3:
>>>>>
>>>>>   - change cppc_get_reg() and cppc_set_reg() name to cppc_get_reg_val() and
>>>>>     cppc_set_reg_val()
>>>>>   - extract cppc_get_reg_val_in_pcc() and cppc_set_reg_val_in_pcc()
>>>>>   - return the result of cpc_read() in cppc_get_reg_val()
>>>>>   - add pr_debug() in cppc_get_reg_val_in_pcc() when pcc_ss_id < 0
>>>>>   - rename 'cpunum' to 'cpu' in cppc_get_reg_val()
>>>>>   - move some macros from drivers/cpufreq/cppc_cpufreq.c to
>>>>>     include/acpi/cppc_acpi.h with a CPPC_XXX prefix
>>>>>
>>>>> v2:
>>>>>
>>>>>   - fix some incorrect placeholder
>>>>>   - change kstrtoul to kstrtobool in store_auto_select
>>>>>
>>>>> Lifeng Zheng (8):
>>>>>    ACPI: CPPC: Add IS_OPTIONAL_CPC_REG macro to judge if a cpc_reg is
>>>>>      optional
>>>>>    ACPI: CPPC: Optimize cppc_get_perf()
>>>>>    ACPI: CPPC: Rename cppc_get_perf() to cppc_get_reg_val()
>>>>>    ACPI: CPPC: Add cppc_set_reg_val()
>>>>>    ACPI: CPPC: Refactor register value get and set ABIs
>>>>>    ACPI: CPPC: Modify cppc_get_auto_sel_caps() to cppc_get_auto_sel()
>>>>>    ACPI: CPPC: Add three functions related to autonomous selection
>>>>>    cpufreq: CPPC: Support for autonomous selection in cppc_cpufreq
>>>>>
>>>>>   .../ABI/testing/sysfs-devices-system-cpu      |  54 ++++
>>>>>   drivers/acpi/cppc_acpi.c                      | 303 +++++++++++-------
>>>>>   drivers/cpufreq/amd-pstate.c                  |   3 +-
>>>>>   drivers/cpufreq/cppc_cpufreq.c                | 109 +++++++
>>>>>   include/acpi/cppc_acpi.h                      |  30 +-
>>>>>   5 files changed, 372 insertions(+), 127 deletions(-)
>>>>>
>>>>
>>>> Gentle ping.
>>>
>>> OK, so I'm wondering how this is related to the patch series at
>>>
>>> https://lore.kernel.org/linux-acpi/20250211103737.447704-1-sumitg@nvidia.com/
>>
>> This series refactors some cppc_acpi ABIs and supports cppc autonomous
>> selection with sysfs files in cpufreq policy.  Later, [1] proposed another
>> design with different user interfaces.We will discuss and reach a consensus
>> with regard to this.
>>
>> However, as mentioned in [1], patch 1-7 in this series (the cppc_acpi part)
>> are not related to user interfaces, so can be reviewed and applied
>> separately.  I can also send patch 1-7 as a new thread if preferred.
>>
>> [1] https://lore.kernel.org/linux-acpi/20250211103737.447704-1-sumitg@nvidia.com/
> 
> I tried the patchset on a platform which doesn't implement CPC and everything worked well.
> As Lifeng said,
>   PATCH v5 8/8] cpufreq: CPPC: Support for autonomous selection in cppc_cpufreq
> seems to be still in discussion, but for patches 1-7 FWIW:
> 
> Reviewed-by: Pierre Gondois <pierre.gondois@arm.com>

Thank you!

Regards,
Lifeng

> 
> Regards,
> Pierre
> 
>>
>>>
>>>> Attach discussions of previous versions:
>>>> v1: https://lore.kernel.org/all/20241114084816.1128647-1-zhenglifeng1@huawei.com/
>>>> v2: https://lore.kernel.org/all/20241122062051.3658577-1-zhenglifeng1@huawei.com/
>>>> v3: https://lore.kernel.org/all/20241216091603.1247644-1-zhenglifeng1@huawei.com/
>>>> v4: https://lore.kernel.org/all/20250113122104.3870673-1-zhenglifeng1@huawei.com/
>>>>
>>>
>>
>>
>