Re: [RFC PATCH 0/7] arm64: Add fit images for sc7180-trogdor and google,lga

[Doug Anderson]

Hi,

On Fri, Oct 30, 2026 at 6:09 PM Doug Anderson <dianders@xxxxxxxxxxxx> wrote:
>
> > The FIT_ITS path is a second way to build image.fit alongside
> > make_fit.py, and much of it repeats what make_fit.py already does: it
> > puts the root compatible from each DTB into the configuration and
> > compresses the DTBs. The series adds fdtget/fdtput, sed parsing of
> > /incbin/ paths and a shell loop in Makefile.lib to do the same for a
> > hand-written .its file, and the .its files repeat the DTB lists from
> > the Makefiles.
> >
> > Have you thought about extending make_fit.py to take the per-board
> > metadata (e.g. from a small file next to the DTs, or via
> > FIT_EXTRA_ARGS) and to run fdtfactor itself? That would avoid the
> > in-tree fdtget/fdtput, the mkimage dependency and most of the Makefile
> > logic, and trogdor would come almost for free.
>
> I certainly can do that if that's what people want. ...and, yes, I
> think it would simplify some stuff in this patch series. The
> question is: what does it look like? Is it a file that is a list
> of devicetrees along with descriptions? The list of devicetrees
> would be to limit which devicetrees are built into the FIT
> and then each would have a description. ...and yes, that would mean
> it would need to be updated in parallel with the Makefile, but I
> don't see a significantly better way to do it. Yeah, I guess that
> could work OK.
>
> If so, I think a bunch of the patches in this series will be
> dropped or look very different. I probably won't directly reply
> to your comments on patch 2, 4, 6, and 7 if we go this way.
>
> Should I give it a shot for v2?

FWIW, I did a quick prototype of this, and it is definitely a much
smaller / less invasive patch series. I've got
"sc7180-trogdor.fitconfig" and "lga.fitconfig" files. Because they are
easy to parse in python, they're in ".ini" format in my prototype. So
"lga.fitconfig" looks like this:

+# SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
+#
+# Each configuration description encodes board and SoC matching metadata
+# for downstream packaging tools in the format:
+#   "<Model> (<key>=<value>,...)"
+# where <key> includes board_id, board_rev, soc_id, and soc_rev with
+# hexadecimal <value>s (in any key order).
+
+[lga-blazer.dtb]
+description = Blazer
(board_id=0x070406,board_rev=0x010000,soc_id=0x0005,soc_rev=0x010000)
+
+[lga-frankel.dtb]
+description = Frankel
(board_id=0x070306,board_rev=0x010000,soc_id=0x0005,soc_rev=0x010000)
+
+[lga-mustang.dtb]
+description = Mustang
(board_id=0x070506,board_rev=0x010000,soc_id=0x0005,soc_rev=0x010000)


Happy to post a v2 RFC showing what that looks like if you want...