Dual display not working in imx8mq-evk

[SJ22]

Hi,

I connected imx-mipi-hdmi connecter to imx8mq-evk board for enabling dual display, so during u-boot , i loaded a dts file named imx8mq-evk-dual-display.dtb where I have enabled mipi_dsi node, even after that nothing is coming in display. 

I am getting this issue while booting :adv7511 2-003d: Probe failed. Remote port 'mipi_dsi@30a00000' disabled

But I have enabled these nodes in the dts files. Do you know what might be the issue.

[marktsai1989]

Hi @Sanket_Parekh 

Can VPU in IMX8MQ support color space conversion and scaling ?

[Sanket_Parekh]

Hi @SJ22 

I hope you are doing well.

There are many changes in imx8mq-evk.dts file between 5.4 and the latest kernel version.

It is not recommended to make changes to the latest device tree in the 5.4 kernel.

Please make sure that you have followed the below steps in u-boot.

=> setenv fdt_file imx8mq-evk-dual-display.dts
=> saveenv

Please try using kernel provided by nxp.

linux-imx

Please refer to the below article when the dual display is realized in imx8mq

How to use the dual display on i.MX8 including 4k decoding

https://community.nxp.com/t5/i-MX-Processors/Dual-display-kmssik-is-not-working-on-5-4-zeus-build/td...

Please share the part number of both displays connected to the board.

Thanks & Regards,

Sanket Parekh

[SJ22]

Hi @Sanket_Parekh 

I have connected Dell displays (D1918H) 18.5 inch.

[Sanket_Parekh]

Hi @SJ22 ,

I hope you are doing well.

One can compare the current kernel configuration file with the prebuilt image's(5.4.) configuration file.

To obtain a prebuilt image's configuration file on board, use the below command.

 zcat /proc/config.gz > filename.config 

Please provide me with the kernel configuration file.

Please use linux-imx instead of linux-fslc-imx.

Thanks & Regards,

Sanket Parekh

[Sanket_Parekh]

Hi @SJ22 ,

I hope you are doing well.

This issue could be due to the wrong slave address for adv_bridge.

Please share the output of the below command.

# i2cdetect -y 30a40000.i2c

Please mention the BSP version used.

Have you tried using prebuilt images?

Please make sure the below-mentioned options are enabled in the kernel.
CONFIG_DRM_I2C_ADV7511=y
CONIFG_FB_MXC_ADV7535=y

Please refer to AN12188 Quick Start Guide for IMX-MIPI-HDMI for i.MX 8M Evaluation Kit.

Thanks & Regards,

Sanket Parekh

[SJ22]

Hello Sanket,

The output for i2detect is :

imx8mqevk:~# i2cdetect -y 30a40000.i2c
0 1 2 3 4 5 6 7 8 9 a b c d e f
00: -- -- -- -- -- -- -- -- -- -- -- -- --
10: UU UU UU UU -- -- -- -- -- -- -- -- -- -- -- --
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- UU -- --
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- -- 

I am using  linux-fslc-imx kernel whose version is 5.4.114+gitAUTOINC+f9a9b58ef7 ; I am using AGL image for imx8mq-evk board.

I have checked the prebuild image, in that, dual display was working and I compared the dts files , only difference is the use of mipi_dsi_bridge node in the prebuilt image: https://coral.googlesource.com/linux-imx/+/refs/heads/alpha/arch/arm64/boot/dts/freescale/fsl-imx8mq.... The dts file which I am using: https://github.com/nxp-imx/linux-imx/blob/lf-6.1.y/arch/arm64/boot/dts/freescale/imx8mq-evk-lcdif-ad...

CONFIG_DRM_I2C_ADV7511 is enabled but CONFIG_FB_MXC_ADV7535 is disabled. I think that is where the issue is coming; I have one general doubt I am not finding this option CONFIG_FB_MXC_ADV7535 in menuconfig. This option is present in Kconfig ,but in the menuconfig path -> Device Drivers -> Graphics support -> Frame buffer Devices, this option is not visible. Do you know what might be the issue?

[SJ22]

Hi @Sanket_Parekh ,

one more quick update, I enabled CONFIG_FB_MXC_ADV7535 but still nothing is coming in the hdmi .I am getting this issue: adv7535 2-003d: failed to get required video mode. I have attached the screenshot of the log. So the issue narrows down to the dts files right?

[Sanket_Parekh]

Hi @SJ22 ,

I hope you are doing well.

It is recommended to use BSP provided by NXP for EVK.

Please refer to below document.

i.MX Yocto Project User's Guide

One can use the below options in kernel defconfig.

CONFIG_DRM_I2C_ADV7511=y

CONFIG_DRM_I2C_ADV7511_AUDIO=y

CONFIG_DRM_I2C_ADV7511_CEC=y

This issue could be due to incorrect device tree configurations or version mismatching.

Please refer to below dts file for dual display in nxp linux.

imx8mq-evk-dual-display.dts

Above dts supports the below display interface.

1. DCSS + onboard HDMI
2. LCDIF + DSI-HDMI converter: ADV7535

Thanks & Regards,

Sanket Parekh

[SJ22]

Hi @Sanket_Parekh ,

These configurations which you mentioned are all enabled.

CONFIG_DRM_I2C_ADV7511=y

CONFIG_DRM_I2C_ADV7511_AUDIO=y

CONFIG_DRM_I2C_ADV7511_CEC=y

I am using the same dts file imx8mq-evk-dual-display.dts  which is already present in the bsp layer, also tried loading the corresponding dtb file during u-boot but still no use. 

[Sanket_Parekh]

Hi @SJ22 

I hope you are doing well.

Base file (imx8mq-evk.dts ) of imx8mq-evk-dual-display.dts has many changes between linux versions.

like below,

LF-3064 Revert "arm64: dts: imx8mq-evk: Add MIPI DSI support"

Please try using the latest linux kernel source provided by nxp.

https://github.com/nxp-imx/linux-imx.

Thanks & Regards,

Sanket Parekh

[SJ22]

Hi @Sanket_Parekh ,

The dts files I am using is same as what is present in the latest kernel source. Also when I checked one of the prebuild images where the dual display is working,the only difference which I noticed in the dts files is that they have used node called mipi_dsi_bridge which is absent in the link which you gave for the latest kernel source. So I added that particular node but still it was failing.

[SJ22]

Hi @Sanket_Parekh ,

I managed to resolve this particular issue related to adv7511 driver: adv7511 2-003d: Probe failed. Remote port 'mipi_dsi@30a00000' disabled. But still it is not working. I have noticed an absence of this log [ie nwl-mipi-dsi 30a00000.mipi_dsi_bridge: [drm:nwl_dsi_host_attach] lanes=4, format=0x0 flags=0x215] which is related to mipi-dsi-host-attach function call in mipi dsi host controller driver,nwl-dsi.

Currently I am getting these logs:

mxsfb 30320000.lcdif: Failed to get axi clock: 0

[    3.238761] nwl-dsi 30a00000.mipi_dsi: [drm:imx8mq_dsi_select_input] Using LCDIF as input source

I feel like there is some issue with the mipi-dsi-host controller driver and drm. Do you know why that log is absent