[RFC PATCH v2 00/11] Simple QoS for exynos-bus driver using interconnect

Wed Sep 25 06:48:14 UTC 2019

Hi,

On 19. 9. 25. 오후 3:37, Artur Świgoń wrote:
> On Wed, 2019-09-25 at 15:12 +0900, Chanwoo Choi wrote:
>> Hi,
>>
>> On 19. 9. 25. 오후 2:47, Artur Świgoń wrote:
>>> Hi,
>>>
>>> On Fri, 2019-09-20 at 11:14 +0900, Chanwoo Choi wrote:
>>>> Hi Artur,
>>>>
>>>> I tried to just build this patch on mainline kernel or linux-next.
>>>> But, when I applied them, merge conflict happens. You didn't develop
>>>> them on latest version. Please rebase them based on latest mainline kernel.
>>>
>>> I developed on top of next-20190918 on which I applied
>>> https://patchwork.kernel.org/cover/11149497/ as I mentioned in the cover
>>> letter. The dev_pm_qos patches and my RFC have just cleanly rebased together on
>>> top of next-20190920. Could you check if you have the dev_pm_qos patches (v5,
>>> the version number is missing in this one; link above) and if so, where does the
>>> conflict appear?
>>
>> I faced on the merge conflict of drivers/devfreq/exynos-bus.c.
>> I think that It is not related to to dev_pm_qos patch.
> 
> I think that it is actually related to the specific version of dev_pm_qos (v5) that
> I used because patch 08/08 of dev_pm_qos series modifies exynos_bus_probe() in
> drivers/devfreq/exynos-bus.c (https://patchwork.kernel.org/patch/11149507/).
> 
> I will rebase the next RFC (v3) on latest dev_pm_qos patches from Leonard and the
> latest Linux-next kernel.

My mistake. I only checked the Leonard's latest patches(v8)
which doesn't contain this patch. OK. I'll try again. Thanks.
[1] https://patchwork.kernel.org/patch/11149507/
- PM / devfreq: Move opp notifier registration to core

> 
>> Maybe, Kamil's patches[1] changed the many things of exynos-bus.c
>> If your test branch doesn't contain following patches, 
>> you need to rebase your patches based on latest mainline kernel 
>> from Linus Torvald.
>> [1] https://patchwork.kernel.org/cover/11083663/
>> - [RESEND PATCH v5 0/4] add coupled regulators for Exynos5422/5800
> 
> Yes, requiring Kamil's patches is one of the changes in this RFC (v2), since they
> are already merged.
> 
>> Today, I tried to apply these patch again based on latest mainline kernel.
>> The merge conflict happen still.
>>
>> - merge conflict log
>> Applying: devfreq: exynos-bus: Extract exynos_bus_profile_init()
>> error: patch failed: drivers/devfreq/exynos-bus.c:334
>> error: drivers/devfreq/exynos-bus.c: patch does not apply
>> Patch failed at 0001 devfreq: exynos-bus: Extract exynos_bus_profile_init()
>>
>>
>>>
>>>> On 19. 9. 20. 오전 10:07, Chanwoo Choi wrote:
>>>>> Hi Artur,
>>>>>
>>>>> On v1, I mentioned that we need to discuss how to change
>>>>> the v2 for this. But, I have not received any reply from you on v1.
>>>>> And, without your reply from v1, you just send v2.
>>>>>
>>>>> I think that it is not proper development sequence.
>>>>> I have spent many times to review your patches
>>>>> and also I'll review your patches. You have to take care
>>>>> the reply of reviewer and and keep the basic rule
>>>>> of mailing contribution for discussion.
>>>>>
>>>>> On 19. 9. 19. 오후 11:22, Artur Świgoń wrote:
>>>>>> The following patchset adds interconnect[1][2] framework support to the
>>>>>> exynos-bus devfreq driver. Extending the devfreq driver with interconnect
>>>>>> capabilities started as a response to the issue referenced in [3]. The
>>>>>> patches can be subdivided into four logical groups:
>>>>>>
>>>>>> (a) Refactoring the existing devfreq driver in order to improve readability
>>>>>> and accommodate for adding new code (patches 01--04/11).
>>>>>>
>>>>>> (b) Tweaking the interconnect framework to support the exynos-bus use case
>>>>>> (patches 05--07/11). Exporting of_icc_get_from_provider() allows us to
>>>>>> avoid hardcoding every single graph edge in the DT or driver source, and
>>>>>> relaxing the requirement contained in that function removes the need to
>>>>>> provide dummy node IDs in the DT. Adjusting the logic in
>>>>>> apply_constraints() (drivers/interconnect/core.c) accounts for the fact
>>>>>> that every bus is a separate entity and therefore a separate interconnect
>>>>>> provider, albeit constituting a part of a larger hierarchy.
>>>>>>
>>>>>> (c) Implementing interconnect providers in the exynos-bus devfreq driver
>>>>>> and adding required DT properties for one selected platform, namely
>>>>>> Exynos4412 (patches 08--09/11). Due to the fact that this aims to be a
>>>>>> generic driver for various Exynos SoCs, node IDs are generated dynamically
>>>>>> rather than hardcoded. This has been determined to be a simpler approach,
>>>>>> but depends on changes described in (b).
>>>>>>
>>>>>> (d) Implementing a sample interconnect consumer for exynos-mixer targeted
>>>>>> at the issue referenced in [3], again with DT info only for Exynos4412
>>>>>> (patches 10--11/11).
>>>>>>
>>>>>> Integration of devfreq and interconnect functionalities is achieved by
>>>>>> using dev_pm_qos_*() API[5]. All new code works equally well when
>>>>>> CONFIG_INTERCONNECT is 'n' (as in exynos_defconfig) in which case all
>>>>>> interconnect API functions are no-ops.
>>>>>>
>>>>>> This patchset depends on [5].
>>>>>>
>>>>>> --- Changes since v1 [6]:
>>>>>> * Rebase on [4] (coupled regulators).
>>>>>> * Rebase on [5] (dev_pm_qos for devfreq).
>>>>>> * Use dev_pm_qos_*() API[5] instead of overriding frequency in
>>>>>>   exynos_bus_target().
>>>>>> * Use IDR for node ID allocation.
>>>>>> * Avoid goto in functions extracted in patches 01 & 02 (cf. patch 04).
>>>>>> * Reverse order of multiplication and division in
>>>>>>   mixer_set_memory_bandwidth() (patch 11) to avoid integer overflow.
>>>>>>
>>>>>> ---
>>>>>> Artur Świgoń
>>>>>> Samsung R&D Institute Poland
>>>>>> Samsung Electronics
>>>>>>
>>>>>> ---
>>>>>> References:
>>>>>> [1] Documentation/interconnect/interconnect.rst
>>>>>> [2] Documentation/devicetree/bindings/interconnect/interconnect.txt
>>>>>> [3] https://patchwork.kernel.org/patch/10861757/ (original issue)
>>>>>> [4] https://patchwork.kernel.org/cover/11083663/ (coupled regulators; merged)
>>>>>> [5] https://patchwork.kernel.org/cover/11149497/ (dev_pm_qos for devfreq)
>>>>>> [6] https://patchwork.kernel.org/cover/11054417/ (v1 of this RFC)
>>>>>>
>>>>>> Artur Świgoń (10):
>>>>>>   devfreq: exynos-bus: Extract exynos_bus_profile_init()
>>>>>>   devfreq: exynos-bus: Extract exynos_bus_profile_init_passive()
>>>>>>   devfreq: exynos-bus: Change goto-based logic to if-else logic
>>>>>>   devfreq: exynos-bus: Clean up code
>>>>>>   interconnect: Export of_icc_get_from_provider()
>>>>>>   interconnect: Relax requirement in of_icc_get_from_provider()
>>>>>>   interconnect: Relax condition in apply_constraints()
>>>>>>   arm: dts: exynos: Add parents and #interconnect-cells to Exynos4412
>>>>>>   devfreq: exynos-bus: Add interconnect functionality to exynos-bus
>>>>>>   arm: dts: exynos: Add interconnects to Exynos4412 mixer
>>>>>>
>>>>>> Marek Szyprowski (1):
>>>>>>   drm: exynos: mixer: Add interconnect support
>>>>>>
>>>>>>  .../boot/dts/exynos4412-odroid-common.dtsi    |   1 +
>>>>>>  arch/arm/boot/dts/exynos4412.dtsi             |  10 +
>>>>>>  drivers/devfreq/exynos-bus.c                  | 319 +++++++++++++-----
>>>>>>  drivers/gpu/drm/exynos/exynos_mixer.c         |  71 +++-
>>>>>>  drivers/interconnect/core.c                   |  12 +-
>>>>>>  include/linux/interconnect-provider.h         |   6 +
>>>>>>  6 files changed, 327 insertions(+), 92 deletions(-)
>>>>>>
> 
> 
> 
> 


-- 
Best Regards,
Chanwoo Choi
Samsung Electronics