On 08/08/18 01:10, Alexander Graf wrote:
On 07.08.18 09:26, Kristian Amlie wrote:
What I want out of this exercise is to make sure that the EFI path in distro_bootcmd will be able to boot an EFI app on any board, regardless of whether it uses kernel_addr_r or loadaddr. Sounds reasonable, right?
If you enable distro boot for a board, one of the requirement is that kernel_addr_r is set to a reasonable value:
http://git.denx.de/?p=u-boot.git;a=blob;f=doc/README.distro;h=f8e9752a0fa424...
Aha! This link clears up the confusion.
There are several things I could do from here on:
- Keep the current patch, but add "loadaddr" to pxe and extlinux
variants as well to get consistent behavior.
- Reverse order of attempts, and try to use kernel_addr_r first, then
loadaddr. Possibly this could also include a patch to pxe and extlinux to make them behave the same.
- Do nothing, and keep kernel_addr_r as the one and only. IMHO this
implicitly means that loadaddr should be deprecated and removed, given their overlapping meaning, and boards converted to using kernel_addr_r.
I think this is the best option. Just convert boards you care about slowly over to distro boot (which implicitly means they also use kernel_addr_r). For other boards you can not rely on any EFI boot path enumeration anyway, because the boot command doesn't search for EFI binaries ;).
You're right, I had not thought of that. It makes a lot of sense, we will make this part of our recommendation for board porting then.
Thanks!