I am using Imx7 512 MB NAND
Made a image tdx-reference-minimal-image and added display support to it weston. whenever I am using LCD from DWIN (LN80480T050IA4001) am not getting anything on screen not even characters of uboot and kernal. So I followed document from below link Build Linux Kernel from Source Code | Toradex Developer Center
Kernel Git Tag :v6.1.55
for patches
meta-toradex-bsp-common BSP version: 6.3.0
Was able to build kernel (zImage)
after installing it not able to load image into system, I have connected serial port at 115200 Image is halted at Starting kernel …
Things I have observed
Existing zImage file was 9.5 MB and newly created zImage file is 7.5 MB
Am I selecting some wrong repository or BSP version?
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Based on the context provided, it seems like you are experiencing an issue with the display not showing anything after building and installing a new Linux kernel image on your iMX7 512 MB NAND module. Here are a few points to consider:
Kernel Size Difference: The difference in size between the existing zImage (9.5 MB) and the newly created zImage (7.5 MB) could indicate that some necessary components or configurations might be missing in the new build. Ensure that all required drivers and configurations for your display are included in the kernel configuration.
Kernel Configuration: Verify that the kernel configuration used for building the new zImage includes all necessary options for your specific hardware setup, especially for the display. You might need to compare the configuration of the existing working kernel with the new one to identify any missing options.
Device Tree: Ensure that the device tree used with the new kernel is correctly configured for your display. The device tree should describe the hardware setup accurately, including the display interface and any specific settings required by the DWIN LCD.
BSP Version and Git Tag: You mentioned using Kernel Git Tag v6.1.55 and meta-toradex-bsp-common BSP version 6.3.0. Double-check that these versions are compatible with your hardware and that they include support for your specific display.
Serial Output: Since the system halts at “Starting kernel …”, it might be useful to enable early printk or other debugging options in the kernel to get more information about where the boot process is failing.
Patches: Ensure that any necessary patches have been correctly applied to the kernel source, especially if they are required for your specific hardware or display.
If these steps do not resolve the issue, you may need to provide more specific details or consult additional resources or support channels for further assistance.
Please, also check if these links can help you solve your problem:
Hi @bharat_sabne,
As discussed, this could happen due to wrong kernel.
If I remember correctly, you were using the wrong toolchain, please use the correct toolchain and rebuild the kernel.
You also need to update the kernel module if you have made changes in the kernel.
As you suggested, I have rebuild kernel from scratch, and used correct toolchain this time. I did not modify any single file this time just followed instruction from link https://developer.toradex.com/linux-bsp/os-development/build-u-boot-and-linux-kernel-from-source-code/build-linux-kernel-from-source-code/
Now I am facing different issue
[ 2.533844] —[ end Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0) ]—
Hi @bharat_sabne ,
Please write down all the steps you have followed.
Also, in case you dont know, you do not need to replace the kernel to update the device tree.
After compiling kernel, you can compile the device tree and replace the device tree on your colibri iMX7
$ export ARCH=arm
$ export DTC_FLAGS=“-@”
$ export PATH=~/gcc-linaro/bin/:$PATH
$ export CROSS_COMPILE=arm-none-linux-gnueabihf-
3. Used git to clone repository by using tag v6.1.55
4. git clone -b v6.1.55 git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
5. Downloaded patched from git clone meta-toradex-bsp-common.git - Toradex BSP layer, recipes common to all modules
6. Copied patches from meta-toradex-bsp-common/recipes-kernel/linux/linux-toradex-mainline-git to patch folder
7. Applied patches one by one sequentially, few patches were missing from meta-toradex-bsp-common these are mentioned below
Downloaded kernel-config of minimal OS from Artifact Repository Browser
renamed kernel-config to .config & make olddefconfig
Compiled kernel using make -j$(nproc) zImage 2>&1
Made dtb files using make DTC_FLAGS=“-@”
copied zImage and pasted in newly created image replacing exiting one (Path: /home/bharat/linux/arch/arm/boot/zImage), also skipped zImage and installed again with different different combinations (with dtb files)
copied dtb files and replace into same image
Used easy installer to install
Observations
Screen is at 640x480 in Older LCD, in newer nothing is showing attached video for your reference.
After restart screen is not showing anything but able to ping and take tty console using ssh (If we change to older LCD this issue is not there)
Hi @bharat_sabne ,
From your recent ticket, I can see that you were able to see the display and need little bit tweaking of the timings. For that I already shared instructions to you on the email ticket.
I am marking this one as solved.
I have tested the setup with a touchscreen LCD, and everything appears to be working well. However, I’d like to verify the functionality with a non-touch LCD before confirming the final closure. I’ll update you once that’s complete.
