Hi Umut, On Sun, 4 Oct 2026 at 12:46, Umut Tezduyar Lindskog <[email protected]> wrote: > > Thanks Simon, > > Yes, ultimately I want to boot a UKI containing systemd-stub, but I am also > interested in running systemd-boot itself as an EFI application. > > The chain I have in mind on arm64 is roughly: > > U-Boot -> U-Boot EFI implementation -> systemd-boot -> UKI / systemd-stub -> > Linux > > My main question is whether U-Boot’s EFI implementation provides enough of > the UEFI services/protocols expected by systemd-boot and systemd-stub, > without having to use something like an EDK II payload.
I expect so, yes, but I have not tested it. > > The EFI call logging you mention sounds particularly useful for this. Do you > have a pointer to those patches? I would be interested in using it to boot > systemd-boot/UKI and compare the EFI calls actually exercised against what > U-Boot currently implements. It is rejected for mainline [1] but is in the Deinde tree - e.g. see this MR [2]. It is indeed very useful and I have used it to get Windows booting, for example. Regards, Simon [1] https://patchwork.ozlabs.org/project/uboot/cover/[email protected]/ [2] https://concept.deinde.dev/u-boot/u-boot/-/merge_requests/1331 > > Regards, > Umut > > On Sat, Oct 3, 2026 at 4:30 PM Simon Glass <[email protected]> wrote: >> >> Hi Umut, >> >> On Thu, 10 Sept 2026 at 13:14, Umut Tezduyar Lindskog <[email protected]> >> wrote: >> > >> > Hello, >> > >> > My understanding is that u-boot has its own limited UEFI provider >> > implementation unlike some other boot loaders bundling open source UEFI >> > payloads. >> > >> > Has anyone tried to use u-boot's UEFI provider implementation on arm64 >> > with EFI applications systemd-boot and systemd-stub? >> > >> > Using AI, I mapped all the API calls done by these programs to UEFI >> > service / protocol. Most of the text input output functionality and >> > graphics functionality is irrelevant for my purposes. >> > >> > ASCII text mapping table below: >> >> I think you are referring to UKI (which includes the stub)? I have not >> tried it, but there is a good chance that it works. I did send some >> patches for an EFI log which keeps track of the calls which are made. >> >> Regards, >> Simon
