IMX-MIPI-HDMI Linux L4.9.88_2.0.0

[shawnnageli]

I have been working to get the MIPI to HDMI adapter working with L4.9.88_2.0.0 (stock image).  When going into u-boot it could not find fsl-imx8mq-evk-dcss-adv7535.dtb.  It is not installed in the stock image.

I found in the Linux Binary Demo Images - i.MX 8MQuad EVK folder several .dtb files one if which included Image-fsl-imx8mq-evk-dcss-adv7535.dtb.  I copied this to the same directly I found he default dtb file ( /run/media/mmcblk0p1 ).  Once this was installed I was able to set in u-boot to this dtb and ran fine.

HDMI output functioned properly before and now it should display the incoming HDMI input the HDMI-MIPI adapter.  I have an HDMI signal generator and have tried several video formats, resolutions, and frame rates but cannot get it to display anything.  I do see the monitoring trying to display but cannot seem to get an image through.

The adapter is plugged into J1501 as instructed.  

Is there a list of acceptable HDMI resolutions and frame rates?  Is it HDCP compatible?

[rutvij_trivedi]

Hi ,
I am also facing an issue while connecting IMX-MIPI-HDMI to HDMI, but not able to see anything on HDMI.
HDMI still says "No Signal", and not even NXP logo on HDMI.

No other device is connected (i.e camera ), MIPI-HDMI is connected before booting and I'm using fsl-imx8mq-evk-dcss-adv7535.dtb as mentioned in Document Number: AN12188.
Command line argument doesn't have anything related to HDMI its as per below

root@imx8mqevk:~# cat /proc/cmdline

console=ttymxc0,115200 earlycon=ec_imx6q,0x30860000,115200 root=/dev/mmcblk1p2 rootwait rw

In dmesg I'm getting below logs

[    1.018324] msm_serial: driver initialized
[    1.028259] [drm] Initialized
[    1.044338] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
[    1.051028] [drm] No driver support for vblank timestamp query.
[    1.057080] imx-drm display-subsystem: bound imx-dcss-crtc.0 (ops dcss_crtc_ops)
[    1.064615] nwl_dsi-imx mipi_dsi@30A00000: Using DCSS as input source
[    1.071271] nwl-mipi-dsi 30a00000.mipi_dsi_bridge: [drm:nwl_dsi_host_attach] lanes=4, format=0x0 flags=0x215
[    1.081122] imx-drm display-subsystem: bound mipi_dsi@30A00000 (ops imx_nwl_dsi_component_ops)
[    1.101979] random: fast init done
[    1.121371] EDID block is all zeroes
[    1.124967] imx-drm display-subsystem: HDMI-A-1: EDID block 0 invalid.
[    1.134231] nwl-mipi-dsi 30a00000.mipi_dsi_bridge: [drm:nwl_dsi_host_attach] lanes=3, format=0x0 flags=0x215
[    1.134255] [drm] OPIPE_CFG: gamut = 1, nl = 1, pr = 1, pix_format = 875713089
[    1.707337] Console: switching to colour frame buffer device 128x48
[    1.746320] imx-drm display-subsystem: fb0:  frame buffer device
[    1.777984] loop: module loaded

My schematic version is SCH-29615 REV B3.

So is there anything i'm missing here.
Any help would be appreciable.


Regards,
Rutvij Trivedi.

[diegoadrian]

Hello,

Unfortunately, the device that uses the MIPI to HDMI adapter (adv7533) is under NDA, and we cannot access the information of how to program it. However, we recommend you to go with Analog Devices, they can help you with the resolution that can support their chip. 

I apologize for the inconveniences.

Best Regards,

Diego.

[shawnnageli]

I was under the impression it was the ADV7535 from Analog Devices.  Also, from the documentation for this adapter board it indicated that at least an initial driver for the i.MX8 must be supported if you are able get video initially, however; as mentioned earlier it does not appear to work.

https://www.nxp.com/docs/en/application-note/AN12188.pdf 

[diegoadrian]

Hello,

I get confused.

Are you not seeing any video since the beginning? 

If no, please follow the below steps:

The fsl-imx8mq-evk-dcss-adv7535.dtb file is in the Boot imx8mq partition of your SDcard, you can access if you go to the below path:

$cd /run/media/mmcblk1p1/

However, to change the device tree, you will need to make it through u-boot with the below command:

u-boot ->  editenv fdt_file "Press enter and in you will need to change to the new device tree"

u-boot -> saveenv

After that, you will have the video output through the MIPI to HDMI adapter (please take note that you must need to have connected the adapter before the booting since the adapter is an I2C device and needs to have an I2C address).

Best Regards,

Diego. 

[shawnnageli]

Yes, I have video from the beginning.

The development board I have does not contain an SD card. As mentioned in the original post I found a version (Image-fsl-imx8mq-evk-dcss-adv7535.dtb)  in the Linux Binary Demo Images for release 4.9.88_2.0.0  in the source files here -i.MX Software|NXP 

I coped this file over to the internal flash /run/media/mmcblk0p1

I have change the device tree in two different ways:

u-boot ->  setenv fdt_file Image-fsl-imx8mq-evk-dcss-adv7535.dtb

u-boot ->  run bootcmd

u-boot ->  editenv fdt_file " Used Image-fsl-imx8mq-evk-dcss-adv7535.dtb"

u-boot -> saveenv

In BOTH cases it runs this device tress that is shown above.  I no longer see the desktop that comes with fsl-imx8mq-evk.dtb that is the stock device tree.  I see my monitor trying to display something but does not work.  As mentioned I am using an HDMI signal generator that allows me to supply any format and resolution.  In any of the cases I have tried I do not see anything on the monitor.

Is the Image-fsl-imx8mq-evk-dcss-adv7535.dtb file I have the same as the fsl-imx8mq-evk-dcss-adv7535.dtb you mention?  Would this be the issue.  I am confident the device tree is being set correctly.

Thanks,

Shawn

[diegoadrian]

Hello 

Are you using our demo image, or is a custom image?

Furthermore, have you tried connecting the adapter before the booting process? As I mentioned before, the adapter is an I2C device and needs to negotiate the I2C address. 

Best Regards,

Diego.

[shawnnageli]

This is the demo image for 4.9.88_2.0.0.  The only thing being changes is the .dtb file being used.

Yes, the adapter is connected before even powering or booting anything.  I have also tried with the monitor having it plugged in to the MIPI-HDMI adapter before booting and after booting.

Another thing I looked into was dmesg output if I could see anything related to the MIPI-HMDI, adv7535 but did not see anything in particular.  Wanted to see if it was running anything at boot-up.

Thanks,

Shawn

[diegoadrian]

Hello

I apologize for the delay.

Do you know the silicon revision of your board?

Best Regards,

Diego.

[shawnnageli]

Where is the silicon revision of the board located?

Would it be this number: 700-29615 REV A

Shawn

[diegoadrian]

This is not the revision number, but with your schematic's revision, I can check the revision of the i.MX.

Best Regards,

Diego.

[shawnnageli]

Diego,

OK.  The schematics revision is SCH-29615 Rev B3

Shawn

[diegoadrian]

Hello,

According to our schematic, you have the same chip as my board. Please, let me investigate more. 

One more question, you are not using the MIPI-HDMI bridge with the camera module?

Since I have mentioned, both ones have the same I2C address and the i.MX8 during the booting process will not know which device needs to be called.

Best Regards,

Diego.

[shawnnageli]

Diego,

I have been using the camera module at the same time.  I disconnected and ran the MIPI-HDMI bridge by itself but still getting the same results.

I also tried a different video source to the Bridge as well as a different monitor.  As stated before the monitor tries to display something. 

When I run the stock .dtb file I see the NXP logo during boot and the desktop when it is done booting.

Shawn

[haidong_zheng]

I don't quite understand your question,  seem you use HDMI-MIPI as HDMI input ?   For 8M it does not support HDMI input.