[systemd-devel] bootloader time on a non-EFI bootloader

[Lennart Poettering]

On Fri, 10.04.15 10:34, Koen Kooi (koen at dominion.thruhere.net) wrote:

> 
> > Op 9 apr. 2015, om 11:28 heeft Lennart Poettering <lennart at poettering.net> het volgende geschreven:
> > 
> > On Mon, 16.03.15 11:29, Umut Tezduyar Lindskog (umut at tezduyar.com) wrote:
> > 
> >> Hi,
> >> 
> >> I would like to pass the time it was spent in bootloader to systemd.
> >> Is there a kernel command line to pass this information on non EFI
> >> bootloader? Or is there an another way?
> > 
> > I am open to add this, but I really don't want to see tons of
> > different "drivers" to read this data added to systemd. Hence the way
> > I think this should work, is adding a generic interface to the kernel
> > to /sys/firmware/timing or so, where this information can be read
> > from. We'd then make systemd read that. And wherever the information
> > comes from would be a kernel internal decision, and could be
> > implemented in a myriad of different ways for different architectures.
> > 
> > Also note that ACPI 5.0 exports this timing information in a generic
> > way anyway. Given that ACPI is fairly standard and apparently is even
> > what embedded is standardizing on I'd be open to adding native support
> > for parsing this info from ACPI to systemd, if it's easy enough.
> 
> My situation is slightly different: UEFI that loads a linux Image
> directly using the EFI stub, but no ACPI since it’s a devicetree
> platform. What kind of options to I have to get the boottime info?
> Long term I’d like to use gummiboot, but I haven’t tried building it
> for aarch64 yet.

Hmm, I thought EFI implied ACPI?

Lennart

-- 
Lennart Poettering, Red Hat