[Buildroot] [PATCH 1/1] boot/arm-trusted-firmware: use prebuilt BL33 images

Etienne Carriere etienne.carriere at linaro.org
Fri Nov 30 09:53:28 UTC 2018

On Thu, 29 Nov 2018 at 23:04, Thomas Petazzoni
<thomas.petazzoni at bootlin.com> wrote:
> Hello Etienne,
> On Thu, 22 Nov 2018 16:22:28 +0100, Etienne Carriere wrote:
> > This change allows one to build ATF with an externally built
> > BL33 image or with the U-boot as BL33 boot stage.
> >
> > This change introduces a new configuration directive for TF-A to
> > specify when BL33 stage is provided as a prebuilt image:
> >
> > buildroot configuration shall specify the BL33 binary image location:
> >
> > Signed-off-by: Etienne Carriere <etienne.carriere at linaro.org>
> > ---
> >  boot/arm-trusted-firmware/Config.in               | 22 +++++++++++++++++++++-
> >  boot/arm-trusted-firmware/arm-trusted-firmware.mk |  4 ++++
> >  2 files changed, 25 insertions(+), 1 deletion(-)
> Thanks for this contribution. Could you explain the use case/rationale
> for this change ? In which situation do you want to use prebuilt BL33
> images, as opposed to having another Buildroot package that builds (or
> downloads) them ?

Rational is to relax the BR arm-trusted-firmware (ATF) package
regarding support for alternate BL33 boot stages.
Current package supports only U-boot as ATF BL33 and using an
alternate boot stage mandates changes in boot Config.in and

I understand that I did not setup this the right way as my proposal
does not implies BR is the build/install of the alternate boot stage.

an introduce something like ..._BL33_PACKAGE
to specify the package BR shall build as a dependency for ATF  (i.e
In this case ..._BL33_IMAGE would need to provide the BL33 binary
image file name that is expected from directory $(BINARIES), i.e

Or maybe discard this change and if another boot stage shall be
support, one need to propose specific changes in BR ATF for that BL33
boot stage.

Your though?

For info: I have a former change regarding BL32 (instead of BL33) I
have not yet pushed to the ML.
I wait for OP-TEE OS package to land [1] before proposing change in
ATF for OP-TEE as BL32 or an alternate BL32 with the same model as
this alternate BL33.


> Best regards,
> Thomas
> --
> Thomas Petazzoni, CTO, Bootlin
> Embedded Linux and Kernel engineering
> https://bootlin.com

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