AM3359: Combining .dtb and kernel image

Srinivasa Wunnimani1

Intellectual 600 points

Part Number: AM3359

Hi,

I have a AM3359 board with NAND flash.

I am using default tisdk_am335x-evm_defconfig:

Compilation steps is as below:

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- distclean
make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- tisdk_am335x-evm_defconfig
make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- zImage -j4

Booting the kernel as below:

fatload mmc 0:1 0x88000000 am335x-evm.dtb
setenv bootargs console=ttyS0,115200n8 root=/dev/mmcblk0p2
fatload mmc 0:1 0x82000000 zImage
bootz 0x82000000 - 0x88000000

NAND flash is detected, able to make the partitions, erase & write (everything is good).

Attached: Kernel_log_two_images.txt

Next I am I am trying to combine linux image (zImage) & device tree Blob (.dtb) as below:
Below option was enabled by default:

"Boot options --->"

"Use appended device tree blob to zImage (EXPERIMENTAL)"

Used below command to merge .dtb & zImage

cat arch/arm/boot/dts/am335x-evm.dtb >> arch/arm/boot/zImage

Using this single zImage booting the kernel as below:

setenv bootargs console=ttyS0,115200n8 root=/dev/mmcblk0p2
fatload mmc 0:1 0x82000000 zImage
bootz 0x82000000

Here I am able to boot the kernel but only NAND flash is not being detected!!! I am noticing everything is okay except for NAND.
Attached: Kernel_log_single_image.txt

What is the problem with this step?
How do I combile zImage with .dtb to a single zImage OR
How do I combile uImage with .dtb to a single uImage

Regards
Srinivasa

14_Nov_2019.zip

over 6 years ago

0 RonB over 6 years ago

TI__Mastermind 30746 points

Hello,

As you can see the appended device tree blog feature is marked "Experimental" by the Linux community. As such we do not test or validate this feature. Could you please expand on why you feel you need this for your system design or what overall goal you are trying to achieve. Maybe we can suggest alternatives.

Thank you.

0 Srinivasa Wunnimani1 over 6 years ago in reply to RonB

Intellectual 600 points

Hi,

We are upgrading our system to Linux version 4.14. Earlier we did not have DTB concept and our partition table as per the attached sheet “NAND_PARTITIONS.xlsx” tab “Existing Partitions”.

Because of dtb concept we need to fit dtb to Kernel image or put it in seperate partition.

Goal: To maintain the same partition table as in the existing system. Considering this we were trying to combine kernel image with dtb file.

Alternatives: Add seperate partition for dtb.

Option 1: Add a common partition all kernel as shown in tab “Option 1.”

Option 2: Add a separate partition for each kernel as shown in tab “Option 2.”My understanding is option 1 or 2 does not make any difference. Your thought on this please.

If you have any other options other than this, please let us know.

Regards

Srinivasa

8562.NAND_PARTITIONS.xlsx

0 Srinivasa Wunnimani1 over 6 years ago in reply to Srinivasa Wunnimani1

Intellectual 600 points

Hi,

I have come across below article:

Is there any possibility of creatng a fit image as mentioned in demo 2: Build the FIT (Slide 30) using below command?

mkimage -f kernel_fdt_rd.its kernel_fdt_rd.itb

Do we have support for this in TI SDK 05.03.00.07?

Regards

Srinivasa

0 RonB over 6 years ago in reply to Srinivasa Wunnimani1

TI__Mastermind 30746 points

Hi,

Can you try using:

bootm 0x82000000

instead of:

bootz 0x82000000

to boot the combined image in your original post?

Please let us known the results. Thank you.

0 Srinivasa Wunnimani1 over 6 years ago in reply to RonB

Intellectual 600 points

Hi,

Tried the Flattened Image Tree (FIT) option from the below link:

https://support.criticallink.com/redmine/projects/armc8-platforms/wiki/2019_MDK_Release_Guide

Now it is working fine.

Regards

Srinivasa

Processors

Processors forum

AM3359: Combining .dtb and kernel image