Hi Michal,
On Wed, 9 Oct 2024 at 07:21, Michal Simek michal.simek@amd.com wrote:
Hi,
On 10/9/24 03:55, Simon Glass wrote:
Hi Michal,
On Mon, 7 Oct 2024 at 07:05, Michal Simek michal.simek@amd.com wrote:
Adding binman node with target images description can be unwanted feature but as of today there is no way to disable it. Also on size constrained systems it is not useful to add binman description to DTB. Introduce BINMAN_EXTERNAL_DTB Kconfig symbol which allows separate DTB for target from DTB for binman itself.
Signed-off-by: Michal Simek michal.simek@amd.com
Makefile | 2 +- lib/Kconfig | 10 ++++++++++ 2 files changed, 11 insertions(+), 1 deletion(-)
Doesn't this defeat one of the purposes of Binman, i.e. to document images? We do want the .dts to include the image description. What sort of problem is this causing?
We have two boot flows. The first one (default one) is using Xilinx FSBL for SOM initialization with fit image (DTBS) + u-boot.elf + tfa.
The second one is using U-Boot SPL instead of FSBL. This flow is used by buildroot for example.
In perfect world I should describe both of these flows. I sent description for the second as RFC here. https://lore.kernel.org/r/de1b8dbabd5ab7f20d7aac217ec4f5074d39f1da.172846276...
OK I'll take a look.
but it is also reasonable to describe the first flow but I really don't want both descriptions ends up in the target image.
Why not? Knowing what is in the firmware is one of the goals of Binman.
The second part is if you look at RFC and how fit-dtb.blob is composed. It is one DTB + DTBS which are composed from overlays.
xilinx_zynqmp_kria_defconfig has CONFIG_DEFAULT_DEVICE_TREE="zynqmp-smk-k26-revA"
That's why binman node should go to this DTB but because other images are composed with overlays binman node is spread to all DTBs inside FIT image.
It means one binman description is in fit-dtb.blob 14 times which is far from ideal.
Yes, but I think what you are saying is that U-Boot doesn't need the description, so you don't need it to appear in the dtbs in the FIT. Is that right?
If so, then I think we should add a way to remove it, in Binman, perhaps with a property in the top-level binman image.
Third part is that I can't see binman node in DT schema or bindings that's why I expect this will be reported and I can't see any code which removes it before handing off to OS which is required for System Ready IR. And IIRC removing is also problematic for measured boot.
I did start this e.g. [1] but have not got back to it. Help would be appreciated if it is important to you. I am not sure about System Ready IR, but we shouldn't need to remove this.
Also, please add an fdtmap somewhere so the image can be listed.
Regards, Simon
[1] Documentation/devicetree/bindings/mtd/partitions/binman.yaml