Re: How does install-grub work?

[Danny Milosavljevic]

Hi,

On Mon, 29 Aug 2016 23:19:30 +0200
David Craven <address@hidden> wrote:

> So I'd say the next steps are:
> 
> 1. Pick out your changes that are related to renaming grub to
> bootloader and add a shim for the uboot parts. That should be enough
> to get vm's booting.

Yes. Note that Ludo said that it might make sense to separate the build side 
(gnu/build/install.scm and gnu/build/vm.sc) from the host side (other stuff) 
also for the patches.

> 2. Add your extlinux.conf generation/install code.

Yes. This one is the most important part.

On the other hand, Part 3 below is actually not that important even for actual 
ARM hardware. Usually U-Boot is there when you buy it anyway - usually there's 
no need to fiddle with it directly.

> 3. We can still add an install uboot to MBR procedure if it's necessary.

Sometimes MBR, sometimes random location in the middle of nowhere with a 
magical sector number.

There's still a "FIXME" in gnu/build/install.scm install-bootloader about how 
to detect on the build side which bootloader to use and then call either 
install-grub or install-u-boot. I don't know how to do that. I've asked before 
about whether it's (1) possible and (2) desireable to just compare the 
config-filename to "extlinux.conf" and hardcode u-boot then. But *which* u-boot 
package does it use? How would it know?

This is a very important part that is both missing and necessary - and I've not 
found an answer to that so far.

> This would break the changes down into easy to review patches and subgoals...

Yes, I agree that that would be good.