[PATCH v2 0/7] drm/exynos: more cleanup with super device support

[Andrzej Hajda]

On 04/03/2014 11:05 AM, 대인기 wrote:
> Hi Andrzej,
>
>> Hi Inki,
>>
>> On 04/01/2014 02:37 PM, Inki Dae wrote:
>>> This patch series cleans up exynos drm framework and kms sub drivers
>>> using the component framework[1].
>> I have tested it on trats platform (fimd + dsi), it works.
>> However it seems to be suboptimal.
>> In case of deferred probing of any of components (due to lack of some
>> resources, ex. clock, regulator, phy), all components
>> which were already bound are unbound and re-bound later when another
>> driver is added, this causes multiple unnecessary free/re-allocate cycles.
> The components bound and then unbound wouldn't be bound again because the components unbound are removed component_list like below,
>
> ret = try_to_bring_up_masters(component);
> if (ret < 0) {
>        list_del(&component->node);
>        kfree(component);
> }
>
> And I cannot see that components are freed and re-allocated repeatedly. See the below log,
>
> [    1.425000] [drm] Initialized drm 1.1.0 20060810
> [    1.430000] exynos-drm-ipp exynos-drm-ipp: drm ipp registered successfully.
> [    1.435000] exynos4-fb 11c00000.fimd: adding component (ops fimd_component_ops)
> [    1.445000] exynos-dsi 11c80000.dsi: adding component (ops exynos_dsi_component_ops)
> [    1.450000] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
> [    1.455000] [drm] No driver support for vblank timestamp query.
> [    1.465000] exynos-drm display-subsystem.8: binding 11c00000.fimd (ops fimd_component_ops)
> [    1.470000] exynos-drm display-subsystem.8: bound 11c00000.fimd (ops fimd_component_ops)
> [    1.480000] exynos-drm display-subsystem.8: binding 11c80000.dsi (ops exynos_dsi_component_ops)
> [    1.490000] exynos-drm display-subsystem.8: failed to bind 11c80000.dsi (ops exynos_dsi_component_ops): -12
> [    1.500000] exynos-drm display-subsystem.8: master bind failed: -12
> [    1.505000] exynos-dsi: probe of 11c80000.dsi failed with error -12
Here you have error -12 - ENOMEM, so everything just fails, and this is
OK. The problem is in case of deferred probe.
Good way to simulate it is to make mipi-phy driver as module and insmod
it from userspace.

Regards
Andrzej

>
> I have tested it on universal, trats, trats2 boards. And they all work fine.
> But there was one thing I missed. That is that dpi probe and remove shoudn't be called if fimd node has no port node. For this, I posted it again.
>
> Did you check it again? It seems your missing something. And Can you tell me more details how did you test it? If there is no any problem, I'm going to have pull request today or tomorrow.

The problem I have described has nothing to do with dpi, in fact dpi
driver was disabled in this test.
Anyway I will test DPI separately.

>
> Thanks,
> Inki Dae
>
>> Maybe I miss something, but I guess registration list(s) + DT super-node
>> should perform better.
>>
>> Here is sample log from trats with mipi-phy driver delayed probe:
>>
>>  binding 11c00000.fimd (ops fimd_component_ops)
>>  bound 11c00000.fimd (ops fimd_component_ops)
>>  binding 11c80000.dsi (ops exynos_dsi_component_ops)
>>  failed to bind 11c80000.dsi (ops exynos_dsi_component_ops): -517
>>  unbinding 11c00000.fimd (ops fimd_component_ops)
>>  master bind failed: -517
>>  binding 11c00000.fimd (ops fimd_component_ops)
>>  bound 11c00000.fimd (ops fimd_component_ops)
>>  binding 11c80000.dsi (ops exynos_dsi_component_ops)
>>  failed to bind 11c80000.dsi (ops exynos_dsi_component_ops): -517
>>  unbinding 11c00000.fimd (ops fimd_component_ops)
>>  master bind failed: -517
>>  binding 11c00000.fimd (ops fimd_component_ops)
>>  bound 11c00000.fimd (ops fimd_component_ops)
>>  binding 11c80000.dsi (ops exynos_dsi_component_ops)
>>  failed to bind 11c80000.dsi (ops exynos_dsi_component_ops): -517
>>  unbinding 11c00000.fimd (ops fimd_component_ops)
>>  master bind failed: -517
>>  binding 11c00000.fimd (ops fimd_component_ops)
>>  bound 11c00000.fimd (ops fimd_component_ops)
>>  binding 11c80000.dsi (ops exynos_dsi_component_ops)
>>  failed to bind 11c80000.dsi (ops exynos_dsi_component_ops): -517
>>  unbinding 11c00000.fimd (ops fimd_component_ops)
>>  master bind failed: -517
>>  binding 11c00000.fimd (ops fimd_component_ops)
>>  bound 11c00000.fimd (ops fimd_component_ops)
>>  binding 11c80000.dsi (ops exynos_dsi_component_ops)
>>  bound 11c80000.dsi (ops exynos_dsi_component_ops)
>>
>> This log will grow with number of devices probed in-between.
>>
>> Regards
>> Andrzej
>>
>>> And this patch series had been posted for RFC[2].
>>>
>>> Thanks,
>>> Inki Dae