+Lukasz and a few others
Hi Brian,
On 31 August 2015 at 16:38, Brian_Brelsford@dell.com wrote:
Dell Customer Communication
I have a question with respect to the .itb as a complete bootable/execution entity.
OUR PAST DESIGNs:
Our past home grown solutions, much like fit update, is a binary that contains the various components (meaning kernel, root file system, other stuff).
They are copied into hard coded flash locations, bootcmd then does mmc read of kernel, then bootm, kernel goes to hard coded location to get the rootfs, etc.We also have a system that copy’s the kernel and rootfs as files into a ext4 file system, bootcmd does ext4load of kernel, then bootm, kernel knows of file /rootfs, etc.FULL BENEFIT OF .itb
It would seem that the benefit of having everything in the .itb (Kernel, rootfs, dtb, etc).
It can be copied as a single blob, so fwupdate is really just a single copy to your flash device.
Yes that's right.
QUESTIONs:
Is the full intent of the .itb is to leave it all together, kernel, dtb, rootfs, other stuff?
Pull the itb into memory, boot the kernel, it knows how to find the rootfs, etc.
OR
Is the .itb a kernel/dtb , then via bootargs we tell the kernel where rootfs is?
Meaning it is not part of the .itb.
The second option. You can put a ramdisk in the .itb (FIT) but typically that is just used to get the boot started, and you then use a root disk on another device, with bootargs telling the kernel where to find it.
What the open source industry doing?
If I am totally off base please feel free to correct me.
Thank you for your time.
Brian Brelsford
Regards, Simon