[RFC PATCH 6/7] arm64: dts: google: lga: Add lga.its FIT image script

[Douglas Anderson]

Add an Image Tree Source (`lga.its`) describing the FIT image for Google
Tensor G5 (LGA) Pixel 10 family boards (`lga-blazer.dtb`,
`lga-frankel.dtb`, and `lga-mustang.dtb`) with board and SoC ID/revision
metadata in the configuration descriptions, allowing the LGA FIT image
to be built with:

  make \
    FIT_ITS=google/lga.its \
    FIT_FACTOR_DTBS=1 \
    FDTFACTOR_ARGS="--strip-local-fixups --single-base-dtb" \
    image.fit

NOTE: At the moment, Pixel 10 doesn't directly boot from a FIT
image. However, packaging scripts will be able to take an image as
built above and convert it into a format that the bootloader can
handle.

It should also be noted that the "description" of the various
configurations here is expected to be parsed to help figure out which
configuration to use on which board. This idea came out of discussions
at Linux Plumbers Conference 2026 and means we don't need "loader"
info polluting device trees. Having a structured (and upstream) place
to store this data is part of the motivation for landing this FIT
image.

Side note: at the moment, the Pixel bootloader can't handle picking
overlays based on the soc_id and soc_rev (it only uses those to pick
base dtb files), so for now we won't be able to support boards that
might have different SoCs. I've included the soc_id and soc_rev in
this FIT image in the hopes that we can improve the bootloader in the
future, though.

Assisted-by: Gemini:gemini-pro-prerelease
Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
---
Note that building `image.fit` with `lga.its` requires the Pixel 10
(`lga-blazer.dtb`, `lga-frankel.dtb`, and `lga-mustang.dtb`) device
trees, which are currently in linux-next and not yet in mainline.

 arch/arm64/boot/dts/google/lga.its | 68 ++++++++++++++++++++++++++++++
 1 file changed, 68 insertions(+)
 create mode 100644 arch/arm64/boot/dts/google/lga.its

diff --git a/arch/arm64/boot/dts/google/lga.its b/arch/arm64/boot/dts/google/lga.its
new file mode 100644
index 000000000000..5ba19c0b5411
--- /dev/null
+++ b/arch/arm64/boot/dts/google/lga.its
@@ -0,0 +1,68 @@
+// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
+/dts-v1/;
+
+/ {
+	description = "Google Tensor G5 (LGA) kernel and device trees";
+	#address-cells = <1>;
+
+	images {
+		kernel-1 {
+			description = "Linux kernel";
+			data = /incbin/("arch/arm64/boot/Image");
+			type = "kernel_noload";
+			arch = "arm64";
+			os = "linux";
+			compression = "none";
+			load = <0>;
+			entry = <0>;
+		};
+		fdt-1 {
+			description = "lga-blazer.dtb";
+			data = /incbin/("arch/arm64/boot/dts/google/lga-blazer.dtb");
+			type = "flat_dt";
+			arch = "arm64";
+			compression = "none";
+			hash-1 {
+				algo = "sha1";
+			};
+		};
+		fdt-2 {
+			description = "lga-frankel.dtb";
+			data = /incbin/("arch/arm64/boot/dts/google/lga-frankel.dtb");
+			type = "flat_dt";
+			arch = "arm64";
+			compression = "none";
+			hash-1 {
+				algo = "sha1";
+			};
+		};
+		fdt-3 {
+			description = "lga-mustang.dtb";
+			data = /incbin/("arch/arm64/boot/dts/google/lga-mustang.dtb");
+			type = "flat_dt";
+			arch = "arm64";
+			compression = "none";
+			hash-1 {
+				algo = "sha1";
+			};
+		};
+	};
+
+	configurations {
+		conf-1 {
+			description = "Blazer (board_id=0x070406,board_rev=0x010000,soc_id=0x0005,soc_rev=0x010000)";
+			kernel = "kernel-1";
+			fdt = "fdt-1";
+		};
+		conf-2 {
+			description = "Frankel (board_id=0x070306,board_rev=0x010000,soc_id=0x0005,soc_rev=0x010000)";
+			kernel = "kernel-1";
+			fdt = "fdt-2";
+		};
+		conf-3 {
+			description = "Mustang (board_id=0x070506,board_rev=0x010000,soc_id=0x0005,soc_rev=0x010000)";
+			kernel = "kernel-1";
+			fdt = "fdt-3";
+		};
+	};
+};
-- 
2.56.0.212.g129ede20d9-goog