[PATCH] arm64: dts: broadcom: bcm2712-rpi: mark /soc/firmware node as 32-bit

From: Arnd Bergmann

Date: Fri Mar 20 2026 - 11:23:27 EST


From: Arnd Bergmann <arnd@xxxxxxxx>

Moving /soc/firmware to /soc/firmware/rpi-firmware resulted in a build
time warning:

arch/arm64/boot/dts/broadcom/bcm2712-rpi-5-b-base.dtsi:200.4-15: Warning (dma_ranges_format): /soc@107c000000/firmware/rpi-firmware:dma-ranges: empty "dma-ranges" property but its #address-cells (1) differs from /soc@107c000000/firmware (2)

The problem is that while both /soc and /soc/firmware/rpi-firmware are
limited to 32-bit DMA and MMIO addressing, the intermediate /soc/firmware
now gets the default 64-bit addressing, which requires an explicit
translation of the DMA addresses of its 32-bit children.

Mark this one as 32-bit as well for simplicity. Note that this does limit
any other kind of firmware to 32-bit address translation as well, which
might not be ideal in case any of it runs in 64-bit mode. A better solution
may be to move it out of /soc altogether.

Fixes: e3b22edda733 ("arm64: dts: broadcom: bcm2712-rpi: Move the firmware node down 1 level")
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
I'm a bit confused by the changelog test of the e3b22edda733 commit,
which does not appear to match what it actually does. Maybe the intention
was to move /soc/firmware to /firmware/rpi-firmware instead of
/soc/firmware/rpi-firmware? This would also require an explict
dma address translation though.
---
arch/arm64/boot/dts/broadcom/bcm2712-rpi-5-b-base.dtsi | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/arch/arm64/boot/dts/broadcom/bcm2712-rpi-5-b-base.dtsi b/arch/arm64/boot/dts/broadcom/bcm2712-rpi-5-b-base.dtsi
index eddaf72c4e73..c3e71e6aaff6 100644
--- a/arch/arm64/boot/dts/broadcom/bcm2712-rpi-5-b-base.dtsi
+++ b/arch/arm64/boot/dts/broadcom/bcm2712-rpi-5-b-base.dtsi
@@ -191,6 +191,10 @@ wifi: wifi@1 {

&soc {
firmware {
+ #address-cells = <1>;
+ #size-cells = <1>;
+ dma-ranges;
+
firmware: rpi-firmware {
compatible = "raspberrypi,bcm2835-firmware", "simple-mfd";
#address-cells = <1>;
--
2.39.5