Re: [Buildroot] [PATCH v9 05/22] boot/ti-k3-r5-loader: bump to version 2024.01

[Andreas Dannenberg via buildroot <buildroot@buildroot.org>]

Hi Yann,

On Wed, Mar 20, 2024 at 07:14:06AM +0100, Yann E. MORIN wrote:
> Andreas, All,
> 
> On 2024-03-19 21:18 -0500, Andreas Dannenberg via buildroot spake thusly:
> > On Tue, Mar 19, 2024 at 11:09:32PM +0100, Yann E. MORIN wrote:
> > > On 2024-03-04 16:32 +0100, Dario Binacchi spake thusly:
> > > > All in-tree configs with the ti-k3-r5 bootloader use a custom version,
> > > > so this patch is mostly for the menuconfig default version
> [--SNIP--]
> > > Speaking of that, by the way, ti-k3-r5-loader really is uboot, so I
> > > think that it should share:
> > >  1. the same DL_DIR:   TI_K3_R5_LOADER_DL_SUBDIR = uboot
> > >  2. the same hash file:  have ti-k3-r5-loader.hash be a symlink to
> > >     uboot.hash  (and have a xomment at the top of that hash file that it
> > >     is shared and that old hashes should/can be kept)
> > The entire boot chain for TI K3 devices (like all of AM62x) comprising
> > what's known as ti-k3-r5-loaer in Buildroot as well as U-Boot SPL/U-Boot
> > [proper] should _always_ be built from the same U-Boot source commit, as
> > this is how it's developed, tested, and used by pretty much everybody.
> > So your suggestion to more closely tie those things together makes a lot
> > of sense IMHO.
> 
> Ah, interesting, thanks for the feedback.
> 
> So, it looks like for the situation for ti-k3-r5-loaer vs. U-Boot is
> very similar to the one for barebox: it can build a "base" barebox, and
> an "aux" barebox; they both share the same implementation (the
> barebox-package mini-infra), they each provide their own (def|.)config
> file, and they each have their own set of (Buildroot) options (the aux
> one has fewer options).
> 
> So it looks like this is what we should have done for ti-k3-r5-loaer,
> no?

I'm not familiar with barebox but what you are describing looks similar.
Note that ti-k3-r5-loader (building the initial boot binary) is building
for 32-bit ARMv7, and the next boot stages (U-Boot SPL, U-Boot) are all
64-bit ARMv8, so this might complicate any possible unification efforts.
 
> Also, does it make sense to use ti-k3-r5-loaer without U-Boot?

Yes, you could do "Falcon Boot" where the ti-k3-r5-loader would directly
load the Linux kernel, greatly simplifing the boot flow and booting much
MUCH faster. Actually it's a much-requested feature from our customers
(you know, the real world use cases :) so I wrote a technical note [1]
about that last year on how to set this up manually but it would be
great if we could bring this into Buildroot as a package/option somehow
at some point, after we get the base support accepted into the tree.

[1]
https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1205638/faq-am625-how-to-boot-from-r5-u-boot-spl-directly-into-the-linux-kernel-skipping-a53-spl-and-a53-u-boot-falcon-mode


--
Andreas Dannenberg
Texas Instruments Inc




> 
> Regards,
> Yann E. MORIN.
> 
> -- 
> .-----------------.--------------------.------------------.--------------------.
> |  Yann E. MORIN  | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: |
> | +33 662 376 056 | Software  Designer | \ / CAMPAIGN     |  ___               |
> | +33 561 099 427 `------------.-------:  X  AGAINST      |  \e/  There is no  |
> | http://ymorin.is-a-geek.org/ | _/*\_ | / \ HTML MAIL    |   v   conspiracy.  |
> '------------------------------^-------^------------------^--------------------'
_______________________________________________
buildroot mailing list
buildroot@buildroot.org
https://lists.buildroot.org/mailman/listinfo/buildroot