[PATCH v2 0/5] Add runtime PM support for clocks (on Exynos SoC example)

[Marek Szyprowski]

Hi Tobias,


On 2016-10-06 20:05, Tobias Jakobi wrote:
> Hello Marek,
>
> I'm using the patches from the v4.8-clocks-pm-v2 branch plus the ones
> from the v4.8-clocks-pm-v2 branch on top of 4.8.0.
>
> I see some warnings on boot coming from driver core. It appears that the
> warnings are actually meaningful, since IOMMUs stop working completly.
> E.g. if I modprobe s5p-mfc later, firmware loading fails because
> apparantly the IOMMU domain isn't online.
>
>> WARNING: CPU: 0 PID: 1 at drivers/base/core.c:356 device_links_driver_bound+0x124/0x12c
> I added some debug printk() to device_links_driver_bound(), to show the
> link status. Apparantly it is always DEVICE_LINK_AVAILABLE.

Please note that some additional patches are needed to get IOMMU working 
properly with both runtime-pm patches and deferred probe, which feature 
in turn is needed to get it working after adding clocks-pm changes. I 
will send such patch soon (as a new version of IOMMU deferred probe 
support patches were posted a few days ago).

 > (...)

Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland