Dear Team,
I am using RZ/G2L with VLP v3.0.6-update3 with the layers below enabled. I've connected my MIPI LCD panel cwd686 and installed the driver.
I have an issue with getting my GPU up and running. I received these error messages during boot and it seems that my GPU clocks are being disabled. Please let me know how should I troubleshoot this and what do you need from me to guide me?
Thank you in advance,
Winston
I observed that this GPU error only appears when my cwd686 MIPI LCD panel driver is being initialized at the "prepare" stage.
when the mipi_dsi_dcs_set_tear_on() is run, I get a return error -110 after which I start getting errors from the GPU driver. I traced the calls to this function, mipi_dsi_dcs_write_buffer(). Error -110 means "ETIMEDOUT 110 It is displayed if connection is timed out".
My LCD panel is not working so I was trying to fix that then I got this GPU error. I'm thinking MIPI interface is not working?
This is my DTS:
and in r9a07g044.dtsi
winston said:when the mipi_dsi_dcs_set_tear_on() is run, I get a return error -110 after which I start getting errors from the GPU driver. I traced the calls to this function, mipi_dsi_dcs_write_buffer(). Error -110 means "ETIMEDOUT 110 It is displayed if connection is timed out".
This means your driver for your panel is trying to send a DCS command to your LCD.
You could comment that out of your LCD driver and see if that helps.
It might be trying to send DCS commands to your LCD while in the wrong mode.
You are right, Chris. The driver caused the communication error by not setting the MIPI to Low Power Mode (LPM) or single-ended signaling before sending the DCS commands; it is required by the LCD chip, ICNL9707. Now, the LCD panel is working somewhat with some flickering issues. Would you have any idea on the GPU errors? I have already added the layers for the graphics and codecs which is q requirement for the Chromium layer. Do I need to install the Panfrost driver? Thanks in advance.
winston said:Would you have any idea on the GPU errors?
That error is strange. I have not seen that before. Normally an error like that would happen happen when you are creating a driver and forgot a step in the code. But in this case, the code is already complete and the driver was tested.
winston said:Do I need to install the Panfrost driver?
If you installed the graphics package from renesas.com, it includes the Mali driver an library. So you do not need Panforst.
If you want, you can try to use Panfrost instead of the graphic package (calls "ARM DDK") on renesas.com. You have to use one of the other.
Chris
Thanks for reply. When you say the code, do you mean the Mali driver?
Might this error be caused by hardware somehow? I am using the System-On-Module produced by one of Renesas's partner MYIR, MYC-YG2LX CPU Module https://www.myirtech.com/list.asp?id=718. I am using Renesas's latest VLP but using MYIR's hardware. Might that combination caused any issue?
How would you start to troubleshoot this issue if you were me? Where will you start?
Appreciate your help.
I found the issue. It was this one line in the dts file r9a07g044.dtsi that I copied over from MYIR. I used their dts because my custom board is based on their development board.
The offending line was the power-domains = <&cpg>. Commenting it off eliminated the GPU errors completely. I remembered seeing one of the patches from one of Renesas layers removing that line so I thought this could be the issue.
Chris, just out of curiousity, do you know why this line would cause the GPU issue?
Thanks!
Hi winston,
Currently, our out-of-tree GPU uses both pm_runtime API and clk API. So they are conflicted because pm_runtime for RZ/G2L series related to on/off clock gate.
So, you should use only 1 type. Comment out the power-domains to fix it.
Thanks hienhuynh for the explanation!
github.com/.../bc7d081f328a626341acac49a27c09895e9f8312