[PATCH 1/1] riscv: dts: Enable device-tree overlay support for starfive devices

[Palmer Dabbelt]

On Tue, 27 Jun 2023 01:06:20 PDT (-0700), felix.moessbauer at siemens.com wrote:
> Add the '-@' DTC option for the starfive devices. This option
> populates the '__symbols__' node that contains all the necessary symbols
> for supporting device-tree overlays (for instance from the firmware or
> the bootloader) on these devices.
>
> The starfive devices allow various modules to be connected and this
> enables users to create out-of-tree device-tree overlays for these modules.
>
> Please note that this change does increase the size of the resulting DTB
> by ~20%. For example, with v6.4 increase in size is as follows:
>
> jh7100-beaglev-starlight.dtb 6192 -> 7339
> jh7100-starfive-visionfive-v1.dtb 6281 -> 7428
> jh7110-starfive-visionfive-2-v1.2a.dtb 11101 -> 13447
> jh7110-starfive-visionfive-2-v1.3b.dtb 11101 -> 13447
>
> Signed-off-by: Felix Moessbauer <felix.moessbauer at siemens.com>
> ---
>  arch/riscv/boot/dts/starfive/Makefile | 6 ++++++
>  1 file changed, 6 insertions(+)
>
> diff --git a/arch/riscv/boot/dts/starfive/Makefile b/arch/riscv/boot/dts/starfive/Makefile
> index 170956846d49..0141504c0f5c 100644
> --- a/arch/riscv/boot/dts/starfive/Makefile
> +++ b/arch/riscv/boot/dts/starfive/Makefile
> @@ -1,4 +1,10 @@
>  # SPDX-License-Identifier: GPL-2.0
> +# Enables support for device-tree overlays
> +DTC_FLAGS_jh7100-beaglev-starlight := -@
> +DTC_FLAGS_jh7100-starfive-visionfive-v1 := -@
> +DTC_FLAGS_jh7110-starfive-visionfive-2-v1.2a := -@
> +DTC_FLAGS_jh7110-starfive-visionfive-2-v1.3b := -@
> +
>  dtb-$(CONFIG_ARCH_STARFIVE) += jh7100-beaglev-starlight.dtb
>  dtb-$(CONFIG_ARCH_STARFIVE) += jh7100-starfive-visionfive-v1.dtb

Acked-by: Palmer Dabbelt <palmer at rivosinc.com>