Re: [PATCH 4/4] arm64: dts: google: Add initial dts for frankel, blazer, and mustang
From: Krzysztof Kozlowski <krzk@kernel.org>
Date: 2025-11-12 08:14:17
Also in:
linux-devicetree, linux-samsung-soc, lkml
On 11/11/2025 20:22, Douglas Anderson wrote:
Add barebones device trees for frankel (Pixel 10), blazer (Pixel 10
Pro), and mustang (Pixel 10 Pro XL). These device trees are enough to
boot to a serial prompt using an initramfs.
Many things can be noted about these device trees:
1. They are organized as "dts" files for the main SoC and "dtso"
overlays for the boards. There is discussion about this in the
bindings patch ("dt-bindings: arm: google: Add bindings for
frankel/blazer/mustang").
2. They won't boot with the currently shipping bootloader. The current
bootloader hardcodes several paths to nodes that it wants to update
and considers it a fatal error if it can't find these nodes.
Interested parties will need to wait for fixes to land and a new
bootloader to be rolled out before attempting to use these.
3. They only add one revision (MP1) of each of frankel, blazer, and
mustang. With this simple barebones device tree, there doesn't
appear to be any difference between the revisions. More revisions
will be added as needed in the future. The heuristics in the
bootloader will pick the MP1 device tree if there are not any
better matches.
4. They only add the dts for the B0 SoC for now. The A0 SoC support
can be added later if we find the need.
5. Even newer versions of the bootloader will still error out if they
don't find a UFS node to add calibration data to. Until UFS is
supported, we provide a bogus UFS node for the bootloader. While
the bootloader could be changed, there is no long-term benefit
since eventually the device tree will have a UFS node.
6. They purposely choose to use the full 64-bit address and size cells
for the root node and the `soc@0` node. Although I haven't tested
the need for this, I presume the arguments made in commit
bede7d2dc8f3 ("arm64: dts: qcom: sdm845: Increase address and size
cells for soc") would apply here.
7. Though it looks as if the UART is never enabled, the bootloader
knows to enable the UART when the console is turned on. Baud rate
is configurable in the bootloader so is never hardcoded in the
device tree.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
---
To avoid fragmenting the discussion, IMO:
* Let's have the discussion about using the "dts" for SoC and the
"dtso" for the boards in response to the bindings (patch #1).That's discussion here, bindings are irrelevant to this.
quoted hunk ↗ jump to hunk
* If we want to have a discussion about putting "board-id" and "model-id" at the root of the board overlays, we can have it here. I'll preemptively note that the "board-id" and "model-id" won't show up in the final combined device tree and they are just used by the tool (mkdtimg). We could change mkdtimg to parse the "compatible" strings of the overlays files (since I've put the IDs there too), but official the docs [1] seem to indicate that top-level properties like this are OK. In order for these device trees to pass validation without warnings, it's assumed you have my dtc patches: * https://lore.kernel.org/r/20251110204529.2838248-1-dianders@chromium.org (local) * https://lore.kernel.org/r/20251110204529.2838248-2-dianders@chromium.org (local) [1] https://git.kernel.org/pub/scm/utils/dtc/dtc.git/tree/Documentation/dt-object-internal.txt?h=main arch/arm64/boot/dts/google/Makefile | 9 + arch/arm64/boot/dts/google/lga-b0.dts | 391 ++++++++++++++++++ .../arm64/boot/dts/google/lga-blazer-mp1.dtso | 22 + .../boot/dts/google/lga-frankel-mp1.dtso | 22 + .../boot/dts/google/lga-mustang-mp1.dtso | 22 + .../boot/dts/google/lga-muzel-common.dtsi | 17 + 6 files changed, 483 insertions(+) create mode 100644 arch/arm64/boot/dts/google/lga-b0.dts create mode 100644 arch/arm64/boot/dts/google/lga-blazer-mp1.dtso create mode 100644 arch/arm64/boot/dts/google/lga-frankel-mp1.dtso create mode 100644 arch/arm64/boot/dts/google/lga-mustang-mp1.dtso create mode 100644 arch/arm64/boot/dts/google/lga-muzel-common.dtsidiff --git a/arch/arm64/boot/dts/google/Makefile b/arch/arm64/boot/dts/google/Makefile index a6b187e2d631..276001e91632 100644 --- a/arch/arm64/boot/dts/google/Makefile +++ b/arch/arm64/boot/dts/google/Makefile@@ -1 +1,10 @@ # SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause) + +dtb-$(CONFIG_ARCH_GOOGLE) += \ + lga-blazer-mp1.dtb \ + lga-frankel-mp1.dtb \ + lga-mustang-mp1.dtb + +lga-blazer-mp1-dtbs := lga-b0.dtb lga-blazer-mp1.dtbo +lga-frankel-mp1-dtbs := lga-b0.dtb lga-frankel-mp1.dtbo +lga-mustang-mp1-dtbs := lga-b0.dtb lga-mustang-mp1.dtbodiff --git a/arch/arm64/boot/dts/google/lga-b0.dts b/arch/arm64/boot/dts/google/lga-b0.dts new file mode 100644 index 000000000000..83c2db4f20ef --- /dev/null +++ b/arch/arm64/boot/dts/google/lga-b0.dts@@ -0,0 +1,391 @@ +// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause +/* + * Google Tensor G5 (laguna) SoC rev B0 + * + * Copyright 2024-2025 Google LLC. + */ + +/dts-v1/; + +#include <dt-bindings/interrupt-controller/arm-gic.h> +#include <dt-bindings/interrupt-controller/irq.h> + +/ { + model = "Google Tensor G5 rev B0"; + compatible = "google,soc-id-0005-rev-10", "google,lga";
So that's SoC, thus must not be a DTS file, but DTSI. ... ...
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diff --git a/arch/arm64/boot/dts/google/lga-frankel-mp1.dtso b/arch/arm64/boot/dts/google/lga-frankel-mp1.dtso new file mode 100644 index 000000000000..133494de7a9b --- /dev/null +++ b/arch/arm64/boot/dts/google/lga-frankel-mp1.dtso
And that's a board, so DTS.
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@@ -0,0 +1,22 @@ +// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause +/* + * Google Pixel 10 (frankel) MP 1 + * + * Copyright 2024-2025 Google LLC. + */ + +/dts-v1/; +/plugin/; + +#include "lga-muzel-common.dtsi" + +/ { + board-id = <0x070306>; + board-rev = <0x010000>;
Undocumented ABI, which you cannot document because these properties are not allowed. You cannot have them. Best regards, Krzysztof