Re: [PATCH 0/7] ARM: dts: qcom: msm8974: klte: Enable some hardware

[Brian Masney <masneyb@onstation.org>]

Hi Iskren,

On Tue, Jun 30, 2020 at 05:09:05PM +0300, Iskren Chernev wrote:
> Enable support for various hw found on the Samsung Galaxy S5:
> - touchkey (the two buttons around the home button)
> - touchscreen
> - notification led
> - wifi
> - external SD card
> 
> Please note that for working wifi the correct firmware is needed. Check [1]
> for links and locations.
> 
> Also note, that to actually run a mainline kernel on the klte, you'd need
> to apply this patch [2]. Any feedback on getting this to run on pure
> mainline are welcome.
> 
> [1] https://gitlab.com/postmarketOS/pmaports/-/blob/master/firmware/firmware-samsung-klte/APKBUILD
> [2] https://gitlab.com/postmarketOS/linux-postmarketos/-/commit/765f55b248cd3b231af8431fe2f2aeca263b4e4b

Good to see more msm8974 support upstream!

Regarding the second patch, that should only be needed in order to
use the GPU on these devices. I hope that patch won't be needed once
IOMMU support is added, which is the last major missing piece in order
to have the GPU working upstream. I posted a RFC patch [3] in January
but didn't get any suggestions. I suspect some kind of memory corruption
since the board gets unstable with that patch.

If that hack patch is still needed to use the GPU once IOMMU support is
in place, then I planned to troubleshoot it further by adding some log
statements to various probe functions with and without that patch to see
the probe order between the various subsystems. I suspect the issue is
that a clock isn't ticking yet.

[3] https://lore.kernel.org/lkml/20200109002606.35653-1-masneyb@onstation.org/T/#u

Brian