Hi Sascha:
On 8/24/22 15:07, Sascha Hauer wrote:
Hi Andy Et al.,
On Mon, Aug 22, 2022 at 05:20:15PM +0200, Sascha Hauer wrote:
This series adds support for 4k@30 to the rockchip HDMI controller. This
has been tested on a rk3568 rock3a board. It should be possible to add
4k@60 support the same way, but it doesn't work for me, so let's add
4k@30 as a first step.
I tried adding 4k@60 support the same way, just by adding the missing
fields for 600MHz in the PLL/phy settings. I get a picture on the
screen, but it's not very stable: The monitor often gets black, scans
through the different HDMI inputs and then syncs again. Also when I
re-plug the cable while weston is running I won't get any picture
anymore (the same works fine with lower resolutions). I also tried
the Rock3a 4.19 Kernel which is based on the Rockchip Kernel and I saw
similar problems there.
Do you have an idea what could go wrong there?
4K HDMI output from hdmi need very carefully tuning of HDMI PHY and PLL.
I can make sure that HDMI 4K output on rk3399/rk3288/rk356x are work
fine with our
vendor kernel, but the upstream kernel is only can run at 1080p output,
I have tested
on rk3399 and rk3568-evb1[0]
I am not familiar with hdmi tuning, so I am sorry i can't give detail
idea about this issue,
maybe a more carefully comparison with hdmi driver and pll
configuration between upstream kernel and rockchip 4.19 kernel?
I think you have rk356x evb board, do you have a detail test about 4K
HDMI output with this board? If you have issue about 4k hdmi output
on this board with rockchip 4.19 kernel, we can help to figure it out.
Anyway, I loop Algea to the list, he is maintaining our hdmi
development, but I am sorry to say that he is
also very busy😅
I don't have a rock3a, so I can't confirm the problem you described on
4.19 kernel.
[0]https://patchwork.kernel.org/project/linux-rockchip/patch/20220225075150.2729401-16-s.hauer@xxxxxxxxxxxxxx/
Sascha
