Linux/AM3358: LCD driver configuration

Chandrashekar P

Part Number: AM3358
Other Parts Discussed in Thread: DA8XX, TFP410

Tool/software: Linux

Hello,

I'm using 10.4" LCD display, 24 bit mode. Can anyone guide how i can interface with BBB. Kernel config & dts configuration.

Thanks

over 7 years ago

0 prabhuraj tavag20 over 7 years ago

Expert 2020 points

Hi chandrashekhar,

Have a look at the below links :
processors.wiki.ti.com/.../AM335x_LCD_Controller_Driver's_Guide
processors.wiki.ti.com/.../AM335x_Touchscreen_Driver's_Guide
processors.wiki.ti.com/.../Linux_Core_LCD_Controller_User_Guide

Please share your views.

Thanks,
Prabhuraj
BlackPepper Technologies

0 Chandrashekar P over 7 years ago in reply to prabhuraj tavag20

Intellectual 870 points

Hi,

I have enabled in the kernel, but not able to detect.

Do i need to enable anything in u-boot.

Can you please let me know, which kernel config base i need to take. I got to know latest SDK doesn't support frame buffer need to go with DRM?

Any other debug mechanism to understand what is issue to detect the display.

Thanks,

Shekar

0 prabhuraj tavag20 over 7 years ago in reply to Chandrashekar P

Expert 2020 points

Hi chandrashekhar,

FB driver is obsolete since 3.14 kernel and omapdrm applies to 4.4 and 4.9 kernel. Since you didn't mention about your kernel version, I provided guide for both.
If you are using omapdrm :
Configuring into kernel build:

By default DRM support for LCDC is not built in to the kernel when using omap2plus_defconfig.
Make sure that the following are disabled from .config as the fbdev driver cannot coexist with the DRM driver.
CONFIG_FB_DA8XX
CONFIG_FB_DA8XX_TDA998X
And add:
CONFIG_DRM=y/m
CONFIG_DRM_I2C_NXP_TDA998X=y/m
CONFIG_DRM_TILCDC=y/m

If using modules, it is enough to load tilcdc module, and tda998x module if using beaglebone-black. It does not matter in which order the modules are loaded.

Required Device Tree Nodes:

See .txt files in - Documentation/devicetree/bindings/drm/tilcdc
For Beaglebone-Black see also: Documentation/devicetree/bindings/display/bridge/tda998x.txt
The am335x-boneblack.dts, am335x-evm.dts, and am335x-evmsk.dts have the necessary nodes for LCDC DRM driver

Example Device Tree nodes to enable HDMI with DRM on BeagleBone Black:

&lcdc {
status = "okay";

port {
lcdc_0: endpoint@0 {
remote-endpoint = <&hdmi_0>;
};
};
};
&i2c0 {
tda19988: tda19988 {
compatible = "nxp,tda998x";
reg = <0x70>;

#sound-dai-cells = <0>;
audio-ports = < TDA998x_I2S 0x03>;

ports {
port@0 {
hdmi_0: endpoint@0 {
remote-endpoint = <&lcdc_0>;
};
};
};
};
};

More details you can refer from this guide :
processors.wiki.ti.com/.../Linux_Core_LCD_Controller_User_Guide

Thanks,
Prabhuraj
BlackPepper Technologies

0 Chandrashekar P over 7 years ago in reply to prabhuraj tavag20

Intellectual 870 points

Thanks Prabhuraj,

You mean to say do i need to use "omap2plus_defconfig" in kernel.

Anything to be done on u-boot side?

Thanks,
shekar

0 prabhuraj tavag20 over 7 years ago in reply to Chandrashekar P

Expert 2020 points

Hi,

BBB has beaglebone_defconfig according to build steps from elinux.org/Building_BBB_Kernel
Also, the TI wiki page mentions about omap2plus_defconfig. So, can you please check if the configs are enabled in your current config file?
Which config file are you using now?
I guess there is no need to add any touchscreen support in u-boot. TO get it working kernel, dts changes should suffice.
Few more questions :
1) Which touch screen are you using?
2) Do you have the touch screen driver with you?
3) Is it directly supported by BBB?
4) Has your touchscreen vendor provided any details regarding configuring it with BBB?

Thanks,
Prabhuraj
BlackPepper Technologies

0 Chandrashekar P over 7 years ago in reply to prabhuraj tavag20

Intellectual 870 points

Thanks Prabhuraj,

I'm using the latest AM335x SDK version "04.00.00.04".

About kernel config i was trying with "tisdk_am335x-evm_defconfig" available in SDK "arch/arm/configs/" folder. In this folder "omap2plus_defconfig" config also available. Please suggest which one i need to take & start building on top of that.

I'm using AA104SL02-T1 module, this have the touchscreen with LCD. I have big concern about LCD bring up compare to touchscreen.
For touch screen i need to TSC30 support, we are using USB touchscreen. We can bring up touchscreen no issue.

Please find the attached kernel config, dts & kernel log. Kernel_Log_Config_Dts.tar.gz

Looking forward your reply.

Thanks.

0 Chandrashekar P over 7 years ago in reply to prabhuraj tavag20

Intellectual 870 points

Hello Prabhuraj,

Now the display is coming up, it ends with displaying "Please wait..." .

If i start matrix by executing the "/etc/init.d/matrix-gui-2.0 start " i got the below response but nothing is coming on the display.

/home/root
Removing stale PID file /var/run/matrix-gui-2.0.pid.
Starting Matrix GUI application.

Can you please let me know how can i resolve this issue.

Thanks.

0 Chandrashekar P over 7 years ago in reply to prabhuraj tavag20

Intellectual 870 points

Hello Prabhuraj,

Can you please reply.

0 prabhuraj tavag20 over 7 years ago in reply to Chandrashekar P

Expert 2020 points

Hi Chandrashekar,

The solution for this problem is discussed in the following threads :
e2e.ti.com/.../2145422
e2e.ti.com/.../1998699

Please got through the links, try out the experiments and share your observations.

Thanks,
Prabhuraj
BlackPepper Technologies

0 Chandrashekar P over 7 years ago in reply to prabhuraj tavag20

Intellectual 870 points

Hello Prabhuraj,

Please check the below kernel log file and let me know what is the issue.

As they suggested i have done the below changes:

/etc/powervr.ini: add DefaultPixelFormat=RGB888
/etc/weston.ini: add gbm-format=rgb888 at section [core]
/etc/profile.d/qt_env.sh: add export QT_QPA_EGLFS_INTEGRATION=none

the following commands need to be executed at boot prompt
=> setenv optargs video=LVDS-1:800x600
=> saveenv

add the LVDS configuration to /etc/weston.ini in a new "output" section, as shown below:
[output]
name=LVDS-1
mode=800x600

I'm using 10.4" LVDS AA104SL02--T1 display with touchscreen

Please reply as ASAP.4162.20Sep17_2.tar.gz

0 prabhuraj tavag20 over 7 years ago in reply to Chandrashekar P

Expert 2020 points

Hi Chandrashekhar,

As per my understanding, your tilcdc is up so you are able to see the arm-arago projects print on the touch screen. Congrats for that.
Now your matrix-gui is not turning up because omapdrm is failing and wayland/weston is also failing.. I didn't see much log of omapdrm. Please look into this and let me know your views.

Thanks,
Prabhuraj
BlackPepper Technologies

0 Chandrashekar P over 7 years ago in reply to prabhuraj tavag20

Intellectual 870 points

Thanks Prabhuraj,

I have enabled in the kernel all OMAPDRM external display device drivers as static and test, but same result can you please check once the kernel log file.

Please check & suggest the solution. 21Sep17_3.tar.gz

Thanks.

0 prabhuraj tavag20 over 7 years ago in reply to Chandrashekar P

Expert 2020 points

Hi Chandrashekhar,

I went through your logs. Are you sure that you have enabled these options ?
CONFIG_DRM=y
CONFIG_DRM_I2C_NXP_TDA998X=y
CONFIG_DRM_TILCDC=y
Also, do you see /dev/video0 or /dev/video1 which are associated with omapdrm driver?
Follow the links below for more info :
e2e.ti.com/.../1900347
e2e.ti.com/.../522972

Thanks,
Prabhuraj
BlackPepper Technologies

0 prabhuraj tavag20 over 7 years ago in reply to prabhuraj tavag20

Expert 2020 points

Also, can you compile the DRM tests and see what's happening?
processors.wiki.ti.com/.../Graphics_Display_Getting_Started_Guide

thanks,
Prabhuraj
BlackPepper Technologies

0 Chandrashekar P over 7 years ago in reply to prabhuraj tavag20

Intellectual 870 points

Thanks Prabhuraj,

I have enabled the below options:
CONFIG_DRM=y
CONFIG_DRM_I2C_NXP_TDA998X=y
CONFIG_DRM_TILCDC=y

But not able to see /dev/video0 or /dev/video1

When i test the DRM i got the below response:

root@am335x-evm:~/omapdrm-tests-master# ./planescale
assert(common-drm.c:224): : Success

Looking forward your reply.

Thanks

0 Chandrashekar P over 7 years ago in reply to prabhuraj tavag20

Intellectual 870 points

Hello Prabhuraj,

We able to see lcd as "/dev/fb & /dev/fb0" is it fine?

Thanks

0 prabhuraj tavag20 over 7 years ago in reply to Chandrashekar P

Expert 2020 points

Hi Chandrashekhar,

Framebuffer(fb) driver is obsolete in 4.4 and 4.9 kernel. You need to have omaprdrm.

I guess, you have enabled both fb and omapdrm. Can you disable fb configs in kernel and check once?

Thanks,

Prabhuraj

BlackPepper Technologies

0 Chandrashekar P over 7 years ago in reply to prabhuraj tavag20

Intellectual 870 points

Thanks Prabhuraj,

I disabled in kernel config, please find the kernel config but still i'm able to see /dev/fb0. 22Sep2017.tar.gz

After disabled i'm not able to see penguin image while booting & login prompt also. Just back light led is ON.

Thanks

0 Chandrashekar P over 7 years ago in reply to prabhuraj tavag20

Intellectual 870 points

Hello Prabhuraj,

Can you please give some input on the below log:

[ 1.047832] [drm] Initialized
[ 1.052990] exynos-drm-ipp exynos-drm-ipp: drm ipp registered successfully.
[ 1.060753] ---------------drm_platform_init---------------

[ 1.066509] ***************drm_get_platform_dev***************

[ 1.073558] [drm:exynos_drm_load] *ERROR* no device found for DMA mapping operations.
[ 1.081930] exynos-drm exynos-drm: master bind failed: -19
[ 1.088815] Error: Driver 'tfp410' is already registered, aborting...

I have added few debug messages to drm_pci.c file to debug the issue.

Thanks.

0 prabhuraj tavag20 over 7 years ago in reply to Chandrashekar P

Expert 2020 points

Hi,

If you are using TI platform then exynos is not required. Disable it and then see whats happening.

Thanks,

Prabhuraj

BlackPepper Technologies

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Linux/AM3358: LCD driver configuration