On Wed, Dec 29, 2021 at 05:04:17PM +0100, Mark Kettenis wrote: > > From: François Ozog <francois.o...@linaro.org> > > Date: Wed, 29 Dec 2021 14:39:36 +0100 > > > > HI Simon > > > > On Wed, 29 Dec 2021 at 14:36, Simon Glass <s...@chromium.org> wrote: > > > > > Hi François, > > > > > > On Tue, 28 Dec 2021 at 03:15, François Ozog <francois.o...@linaro.org> > > > wrote: > > > > > > > > > > > > > > > > Le mar. 28 déc. 2021 à 09:32, Simon Glass <s...@chromium.org> a écrit : > > > >> > > > >> Hi Masahisa, > > > >> > > > >> On Tue, 21 Dec 2021 at 00:37, Masahisa Kojima > > > >> <masahisa.koj...@linaro.org> wrote: > > > >> > > > > >> > Hi Takahiro, > > > >> > > > > >> > On Tue, 21 Dec 2021 at 11:47, Takahiro Akashi > > > >> > <takahiro.aka...@linaro.org> wrote: > > > >> > > > > > >> > > On Mon, Dec 20, 2021 at 06:25:05PM +0900, Masahisa Kojima wrote: > > > >> > > > Hi Heinrich, Ilias, Akashi-san, > > > >> > > > > > > >> > > > Ilias and I are now discussing to create efi bootmenu, almost > > > similar > > > >> > > > to UiApp in EDK2. > > > >> > > > > > >> > > Why not discuss this topic openly in ML? > > > >> > > > > >> > Yes, I included U-Boot ML.(Sorry, I should include from the the > > > beginning.) > > > >> > > > > >> > > > > > >> > > How is this feature related to Simon's bootmethod proposal? > > > >> > > > > >> > If I correctly understand Simon's bootmethod proposal, > > > >> > the difference is that efi bootmenu only targets to implement > > > >> > the menu based UI to select/edit/add/delete "Boot####" and > > > "BootOrder". > > > >> > > > >> Yes, EFI would be one of the bootmethods. Others would be U-Boot > > > >> scripts, Chrome OS, Android, etc. plus people might add custom ones. > > > >> > > > >> Also I am thinking that (perhaps) the bootdev part of the standard > > > >> boot thing could be used to provide boot devices for EFI. > > > >> > > > >> If we do have a bootmenu, I wonder if it could be generic, instead of > > > >> tied to EFI? > > > > > > > > EFI BootXXXX specify an array of device paths and boot options. A device > > > path is quite a unique construct despite its name. > > > > A device path is itself an array of elements, some elements can be a > > > file path , configuration information, or diverse metadata. An example of > > > configuration information element is UART baud,stop bits, parity along > > > with > > > terminal (vt100, ansi…). Another device path element can cover IP address, > > > transport information (tcp, UDP and port number). > > > > The traditional EFI boot menu is quite crude and does not expose the > > > full capabilities of BootXXXX (lacks edit of boot options for instance!). > > > > > > > > In the long run we will need to leverage all the BootXXXX capabilities > > > and those are EFI specific while being OS agnostic. > > > > The other U-Boot boot methods (Android , ChromeOS…) are OS specific. > > > > The goals are thus very different and making a generic approach seems > > > quite compromised. If there is a fully generic framework available in the > > > future, it may be possible to integrate the EFI boot menu. But at least > > > there is a need to solve, code first, the EFI complexities to fuel the > > > generic architecture discussion. > > > > > > Despite this, the goal of standard boot is to encompass all of this > > > within U-Boot. I believe that it will be successful, even if the path > > > at present is a bit unclear. > > > > > So I would suggest we work bottom up. Starting by making EFI menu work, > > then extend it more generic or integrated it in a framework. Starting top > > down would require a long architecture process based on not enough known > > problems to solve for each environment. > > > > Well, whatever you do, please build something that works well with a > serial console. EDK2 makes assumptions the terminal emulation on the > other side, insists on changing the colors to white on black and > relies on function keys that need escape sequences. And escape > sequences over serial are always iffy since they depend on timing for > their interpretation. You can do better for U-Boot. > > Also, keep in mind that BootOrder and Boot#### only really work if > there is runtime EFI variable support. So the boot menu should > include options to select a device to boot from and use the default > (removable media) bootloader from the ESP on that device.
I think that this issue can/should be addressed in a separate patch although I have had no progress on my patch[1]. -Takahiro Akashi [1] https://lists.denx.de/pipermail/u-boot/2021-November/466583.html > And a way > to make this selection stick! Pretty much all x86 EFI implementations > provide functionality like that. I suppose this could be done by > populating the EFI variable store with appropriate Boot#### variables > and manipulating BootOrder. But that would make it hard to generalize > the boot menu to non-EFI boot flows.
