[U-Boot] [PATCH 5/5] ls2080ardb: Convert to distro boot

[Alexander Graf]

On 16.05.16 14:04, Bhupesh Sharma wrote:
> 
> 
>> -----Original Message-----
>> From: Alexander Graf [mailto:agraf at suse.de]
>> Sent: Monday, May 16, 2016 1:09 PM
>> To: Amit Tomer <amittomer25 at gmail.com>
>> Cc: Bhupesh Sharma <bhupesh.sharma at nxp.com>; york sun
>> <york.sun at nxp.com>; u-boot at lists.denx.de; Peter Newton
>> <peter.newton at nxp.com>
>> Subject: Re: [U-Boot] [PATCH 5/5] ls2080ardb: Convert to distro boot
>>
>>
>>
>>> Am 16.05.2016 um 08:58 schrieb Amit Tomer <amittomer25 at gmail.com>:
>>>
>>>> On Sun, May 15, 2016 at 2:51 AM, Bhupesh Sharma
>> <bhupesh.sharma at nxp.com> wrote:
>>>> Note that UEFI firmware support is already available on LS2080A-RDB
>>>> and allows Booting distributions like CentOS on the same.
>>>
>>> Sorry to intervene here but it's about having the EFI support inside
>>> u-boot itself that may *not* required to have separate UEFI firmware
>>> to boot various distributions.
>>>
>>> Please correct, if it's not right ?
>>
>> It's correct. The idea is to allow everyone to boot using the uEFI
>> entry point in Linux (or any other OS), regardless of whether they want
>> to run U-Boot or a TianoCore based formware.
>>
>> This might seem useless today for embedded use cases, but some features
>> are only available via an EFI entry, such as kASLR. You can also invoke
>> Linux directly using the "bootefi" command, as Linux is an EFI binary
>> itself. That way the boot path doesn't become much longer than with
>> booti today.
>>
> 
> The default firmware being offered by NXP to boot distros on LS2080A and variants is UEFI.
> 
> EFI application support in u-boot doesn't present a solution to things like run-time variable/service
> support that is required by distros to update firmware components on the go. And there are several
> other services being offered by UEFI to help distro boot e.g. secure uefi boot through x.509 certifications
> compliant to UEFI specifications.

Don't get me wrong - I think it's great if there is a TianoCore based
firmware for LS2080A. But I didn't get the impression that there is a
TianoCore based firmware for every NXP SoC out there, so enabling all of
them to use the U-Boot provided uEFI implementation is still a win.

That said, there's nothing that keeps us from implementing the bits you
mentioned in U-Boot either. There is support for RTS in U-Boot, we just
didn't convert any drivers (RTC comes to mind first) yet.

There's also no support for uEFI environment variables, but mostly
because most systems I've used this code on so far just didn't have any
storage to put them.

Certification checks also shouldn't be an issue if someone cared enough
about them.

But I don't think we need a discussion of TianoCore vs U-Boot. What
everyone really wants is to have things "just work". And some customers
just prefer U-Boot for various reasons that are outside of my control.
If they can run the same boot path as everyone else, it makes life for
me as distribution vendor easier. And unlike other people in the
community, I don't think being a TianoCore+ACPI messiah is any helpful
for that goal.


Alex