[syslinux] Question about hdt and UEFI

[Gene Cumm]

On Tue, Apr 10, 2018 at 10:18 AM, R S <rene.shuster at bcsemail.org> wrote:
> You mind to elaborate?

Sure.  efi64/com32/hdt/hdt.c32 is compiled for EFI64 and linked for
the COM32 EFI64 format but the source probably contains some raw ASM
commands that don't work on UEFI since they make BIOS calls.

> I'd like to re-use HDT as well, but I was forced to abandon it years ago due
> to lack of UEFI support and lack of development. Heck even the website
> hdt-project is now owned by a domain-grabber (The Syslinux wiki is still
> linking to it when I check 3 weeks ago... might want to remove that link).

Yes, this is unfortunate.  To accomodate BIOS versus EFI, it would
have to abstract some pieces more to only use the BIOS calls in the
BIOS build and instead use EFI calls on EFI builds.

> On Tue, Apr 10, 2018 at 10:10 AM, Gene Cumm <gene.cumm at gmail.com> wrote:
>>
>> On Tue, Apr 10, 2018 at 10:08 AM, R S <rene.shuster at bcsemail.org> wrote:
>> > If I remember correct HDT is a .C32 executable and not .EFI, so no it
>> > will
>> > not work.
>>
>> Syslinux on EFI won't load arbitrary .efi files but there are 3
>> different flavors of COM32 files, one per firmware.
>>
>> > On Tue, Apr 10, 2018 at 10:02 AM, Gene Cumm via Syslinux
>> > <syslinux at zytor.com> wrote:
>> >>
>> >> On Thu, Mar 8, 2018 at 4:43 AM, Nicolas Lécureuil via Syslinux
>> >> <syslinux at zytor.com> wrote:
>> >>
>> >> > i am trying to use hdt with an UEFI install.  It does  not start and
>> >> > freeze.
>> >> >
>> >> > Does someone know if it is supposed to work ?
>> >> >
>> >> > Btw i have enough machines here to do real QA :)
>> >>
>> >> Personally, I have never tried.  The symptoms would seem to indicate
>> >> it's trying to execute some BIOS code and isn't ready for EFI (yet).
>> >>
>> >> Erwan, any insight/thoughts?
>> >>
>> >> --
>> >> -Gene