Hi there,
I need to do changes in the device tree, so I tried to follow the page https://software-dl.ti.com/jacinto7/esd/processor-sdk-linux-rt-jacinto7/08_02_00_01/exports/docs/linux/Foundational_Components_Kernel_Users_Guide.html to get the same one as original, before I do any changes.
I'm using "ti-processor-sdk-linux-j7-evm-08_02_00_03" and on the board is "08.02.00.02" sdcard Linux image.
My steps
make ARCH=arm64 CROSS_COMPILE=aarch64-none-linux-gnu- tisdk_j7-evm_defconfig
make ARCH=arm64 CROSS_COMPILE=aarch64-none-linux-gnu- ti/k3-j721e-sk.dtb
Then, I have got new device tree:
ll arch/arm64/boot/dts/ti/k3-j721e-sk.dtb
Size of this dt is 73.563 bytes only, where original dt on the sd-card has 100.968, which looks already as different dt. Next. I tried to boot Linux.
Correct boot with original dt:
100968 bytes read in 15 ms (6.4 MiB/s)
10670 bytes read in 8 ms (1.3 MiB/s)
2397 bytes read in 8 ms (292 KiB/s)
## Flattened Device Tree blob at 88000000
Booting using the fdt blob at 0x88000000
Loading Device Tree to 000000008fee4000, end 000000008fffffff ... OK
Starting kernel ...
Now, newly compiled dt:
73587 bytes read in 12 ms (5.8 MiB/s)
10670 bytes read in 12 ms (868.2 KiB/s)
failed on fdt_overlay_apply(): FDT_ERR_NOTFOUND
base fdt does did not have a /__symbols__ node
make sure you've compiled with -@
2397 bytes read in 10 ms (233.4 KiB/s)
failed on fdt_overlay_apply(): FDT_ERR_BADMAGIC
base fdt does did not have a /__symbols__ node
make sure you've compiled with -@
ERROR: Did not find a cmdline Flattened Device Tree
Could not find a valid device tree
As seen, my newly compiled dt is not working, so I did disassembly of original and of my dt - the biggest difference is missing __symbols__ section at the end of the file in my dt, as already uboot reported plus missing or different phandle and other elements.
My question: what I did wrong and how to compile dt to get the same file, as on the sd-card.
Thanks
Best regards,
Tomas
