arm64: broadcom: bcm2712: Rework rp1 overlay handling

[RFC PATCH] arm64: broadcom: bcm2712: Rework rp1 overlay handling

Posted by Rob Herring (Arm) 2 months, 3 weeks ago

It's a requirement that DT overlays be applied at build time in order to
validate them as overlays are not validated on their own.

Simply adding a build time target is possible, but it's also not desirable
to have targets which include the overlay contents and apply the same
overlay.

Rework the targets such that there are 2 overlays: the existing RP1 overlay
and the board specific configuration of the RP1 (bcm2712-rpi-5-b.dtso).

Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
---
The missing applying of rp1.dtbo will soon be a warning[1].

The comment in bcm2712-rpi-5-b.dts(o) needs updating or removing. The RP1
driver or userspace handling of the overlay probably needs updating to
handle the 2 overlays. IIRC, I think we can apply overlays to overlays
which may be useful here. If not, adding that to the tools should be
possible.

[1] https://lore.kernel.org/all/20251114222759.4181152-1-robh@kernel.org/
---
 arch/arm64/boot/dts/broadcom/Makefile                 | 10 ++++++++--
 ...m2712-d-rpi-5-b.dts => bcm2712-d-rpi-5-b-base.dts} |  2 +-
 .../{bcm2712-rpi-5-b.dts => bcm2712-rpi-5-b.dtso}     | 11 +++++------
 3 files changed, 14 insertions(+), 9 deletions(-)
 rename arch/arm64/boot/dts/broadcom/{bcm2712-d-rpi-5-b.dts => bcm2712-d-rpi-5-b-base.dts} (95%)
 rename arch/arm64/boot/dts/broadcom/{bcm2712-rpi-5-b.dts => bcm2712-rpi-5-b.dtso} (92%)

diff --git a/arch/arm64/boot/dts/broadcom/Makefile b/arch/arm64/boot/dts/broadcom/Makefile
index 83d45afc6588..4957edec9d9f 100644
--- a/arch/arm64/boot/dts/broadcom/Makefile
+++ b/arch/arm64/boot/dts/broadcom/Makefile
@@ -6,9 +6,9 @@ DTC_FLAGS := -@
 dtb-$(CONFIG_ARCH_BCM2835) += bcm2711-rpi-400.dtb \
 			      bcm2711-rpi-4-b.dtb \
 			      bcm2711-rpi-cm4-io.dtb \
-			      bcm2712-rpi-5-b.dtb \
+			      bcm2712-rpi-5-b.dtbo \
 			      bcm2712-rpi-5-b-ovl-rp1.dtb \
-			      bcm2712-d-rpi-5-b.dtb \
+			      bcm2712-d-rpi-5-b-base.dtb \
 			      bcm2837-rpi-2-b.dtb \
 			      bcm2837-rpi-3-a-plus.dtb \
 			      bcm2837-rpi-3-b.dtb \
@@ -17,6 +17,12 @@ dtb-$(CONFIG_ARCH_BCM2835) += bcm2711-rpi-400.dtb \
 			      bcm2837-rpi-zero-2-w.dtb \
 			      rp1.dtbo
 
+bcm2712-rpi-5-b-dtbs := bcm2712-rpi-5-b-ovl-rp1.dtb rp1.dtbo bcm2712-rpi-5-b.dtbo
+dtb-$(CONFIG_ARCH_BCM2835) += bcm2712-rpi-5-b.dtb
+
+bcm2712-d-rpi-5-b-dtbs := bcm2712-d-rpi-5-b-base.dtb rp1.dtbo bcm2712-rpi-5-b.dtbo
+dtb-$(CONFIG_ARCH_BCM2835) += bcm2712-d-rpi-5-b.dtb
+
 subdir-y	+= bcmbca
 subdir-y	+= northstar2
 subdir-y	+= stingray
diff --git a/arch/arm64/boot/dts/broadcom/bcm2712-d-rpi-5-b.dts b/arch/arm64/boot/dts/broadcom/bcm2712-d-rpi-5-b-base.dts
similarity index 95%
rename from arch/arm64/boot/dts/broadcom/bcm2712-d-rpi-5-b.dts
rename to arch/arm64/boot/dts/broadcom/bcm2712-d-rpi-5-b-base.dts
index 7de24d60bcd1..48a0ae118839 100644
--- a/arch/arm64/boot/dts/broadcom/bcm2712-d-rpi-5-b.dts
+++ b/arch/arm64/boot/dts/broadcom/bcm2712-d-rpi-5-b-base.dts
@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: (GPL-2.0 OR MIT)
 /dts-v1/;
 
-#include "bcm2712-rpi-5-b.dts"
+#include "bcm2712-rpi-5-b-ovl-rp1.dts"
 
 &gio_aon {
 	brcm,gpio-bank-widths = <15 6>;
diff --git a/arch/arm64/boot/dts/broadcom/bcm2712-rpi-5-b.dts b/arch/arm64/boot/dts/broadcom/bcm2712-rpi-5-b.dtso
similarity index 92%
rename from arch/arm64/boot/dts/broadcom/bcm2712-rpi-5-b.dts
rename to arch/arm64/boot/dts/broadcom/bcm2712-rpi-5-b.dtso
index b8f256545022..89d099c00035 100644
--- a/arch/arm64/boot/dts/broadcom/bcm2712-rpi-5-b.dts
+++ b/arch/arm64/boot/dts/broadcom/bcm2712-rpi-5-b.dtso
@@ -15,19 +15,18 @@
  */
 
 /dts-v1/;
+/plugin/;
 
-#include "bcm2712-rpi-5-b-ovl-rp1.dts"
-
-&pcie2 {
-	#include "rp1-nexus.dtsi"
-};
+#include <dt-bindings/gpio/gpio.h>
 
 &rp1_eth {
 	status = "okay";
 	phy-mode = "rgmii-id";
 	phy-handle = <&phy1>;
+        #address-cells = <1>;
+        #size-cells = <0>;
 
-	mdio {
+	mdio@1 {
 		reg = <0x1>;
 		reset-gpios = <&rp1_gpio 32 GPIO_ACTIVE_LOW>;
 		reset-delay-us = <5000>;
-- 
2.51.0

Re: [RFC PATCH] arm64: broadcom: bcm2712: Rework rp1 overlay handling

Posted by Andrea della Porta 2 months ago

Hi Rob,
sorry for the delay...

On 15:15 Mon 17 Nov     , Rob Herring (Arm) wrote:
> It's a requirement that DT overlays be applied at build time in order to
> validate them as overlays are not validated on their own.
> 
> Simply adding a build time target is possible, but it's also not desirable
> to have targets which include the overlay contents and apply the same
> overlay.
> 
> Rework the targets such that there are 2 overlays: the existing RP1 overlay
> and the board specific configuration of the RP1 (bcm2712-rpi-5-b.dtso).
> 
> Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
> ---
> The missing applying of rp1.dtbo will soon be a warning[1].
> 
> The comment in bcm2712-rpi-5-b.dts(o) needs updating or removing. The RP1
> driver or userspace handling of the overlay probably needs updating to
> handle the 2 overlays. IIRC, I think we can apply overlays to overlays
> which may be useful here. If not, adding that to the tools should be
> possible.
> 
> [1] https://lore.kernel.org/all/20251114222759.4181152-1-robh@kernel.org/
> ---
>  arch/arm64/boot/dts/broadcom/Makefile                 | 10 ++++++++--
>  ...m2712-d-rpi-5-b.dts => bcm2712-d-rpi-5-b-base.dts} |  2 +-
>  .../{bcm2712-rpi-5-b.dts => bcm2712-rpi-5-b.dtso}     | 11 +++++------
>  3 files changed, 14 insertions(+), 9 deletions(-)
>  rename arch/arm64/boot/dts/broadcom/{bcm2712-d-rpi-5-b.dts => bcm2712-d-rpi-5-b-base.dts} (95%)
>  rename arch/arm64/boot/dts/broadcom/{bcm2712-rpi-5-b.dts => bcm2712-rpi-5-b.dtso} (92%)
> 
> diff --git a/arch/arm64/boot/dts/broadcom/Makefile b/arch/arm64/boot/dts/broadcom/Makefile
> index 83d45afc6588..4957edec9d9f 100644
> --- a/arch/arm64/boot/dts/broadcom/Makefile
> +++ b/arch/arm64/boot/dts/broadcom/Makefile
> @@ -6,9 +6,9 @@ DTC_FLAGS := -@
>  dtb-$(CONFIG_ARCH_BCM2835) += bcm2711-rpi-400.dtb \
>  			      bcm2711-rpi-4-b.dtb \
>  			      bcm2711-rpi-cm4-io.dtb \
> -			      bcm2712-rpi-5-b.dtb \
> +			      bcm2712-rpi-5-b.dtbo \
>  			      bcm2712-rpi-5-b-ovl-rp1.dtb \
> -			      bcm2712-d-rpi-5-b.dtb \
> +			      bcm2712-d-rpi-5-b-base.dtb \
>  			      bcm2837-rpi-2-b.dtb \
>  			      bcm2837-rpi-3-a-plus.dtb \
>  			      bcm2837-rpi-3-b.dtb \
> @@ -17,6 +17,12 @@ dtb-$(CONFIG_ARCH_BCM2835) += bcm2711-rpi-400.dtb \
>  			      bcm2837-rpi-zero-2-w.dtb \
>  			      rp1.dtbo
>  
> +bcm2712-rpi-5-b-dtbs := bcm2712-rpi-5-b-ovl-rp1.dtb rp1.dtbo bcm2712-rpi-5-b.dtbo
> +dtb-$(CONFIG_ARCH_BCM2835) += bcm2712-rpi-5-b.dtb
> +
> +bcm2712-d-rpi-5-b-dtbs := bcm2712-d-rpi-5-b-base.dtb rp1.dtbo bcm2712-rpi-5-b.dtbo
> +dtb-$(CONFIG_ARCH_BCM2835) += bcm2712-d-rpi-5-b.dtb
> +
>  subdir-y	+= bcmbca
>  subdir-y	+= northstar2
>  subdir-y	+= stingray
> diff --git a/arch/arm64/boot/dts/broadcom/bcm2712-d-rpi-5-b.dts b/arch/arm64/boot/dts/broadcom/bcm2712-d-rpi-5-b-base.dts
> similarity index 95%
> rename from arch/arm64/boot/dts/broadcom/bcm2712-d-rpi-5-b.dts
> rename to arch/arm64/boot/dts/broadcom/bcm2712-d-rpi-5-b-base.dts
> index 7de24d60bcd1..48a0ae118839 100644
> --- a/arch/arm64/boot/dts/broadcom/bcm2712-d-rpi-5-b.dts
> +++ b/arch/arm64/boot/dts/broadcom/bcm2712-d-rpi-5-b-base.dts
> @@ -1,7 +1,7 @@
>  // SPDX-License-Identifier: (GPL-2.0 OR MIT)
>  /dts-v1/;
>  
> -#include "bcm2712-rpi-5-b.dts"
> +#include "bcm2712-rpi-5-b-ovl-rp1.dts"
>  
>  &gio_aon {
>  	brcm,gpio-bank-widths = <15 6>;
> diff --git a/arch/arm64/boot/dts/broadcom/bcm2712-rpi-5-b.dts b/arch/arm64/boot/dts/broadcom/bcm2712-rpi-5-b.dtso
> similarity index 92%
> rename from arch/arm64/boot/dts/broadcom/bcm2712-rpi-5-b.dts
> rename to arch/arm64/boot/dts/broadcom/bcm2712-rpi-5-b.dtso
> index b8f256545022..89d099c00035 100644
> --- a/arch/arm64/boot/dts/broadcom/bcm2712-rpi-5-b.dts
> +++ b/arch/arm64/boot/dts/broadcom/bcm2712-rpi-5-b.dtso
> @@ -15,19 +15,18 @@
>   */
>  
>  /dts-v1/;
> +/plugin/;
>  
> -#include "bcm2712-rpi-5-b-ovl-rp1.dts"
> -
> -&pcie2 {
> -	#include "rp1-nexus.dtsi"
> -};
> +#include <dt-bindings/gpio/gpio.h>

Sounds reasonable to me, please let me have a full round of tests to check for
any issue with the driver and I'll come back with feedback.

>  
>  &rp1_eth {
>  	status = "okay";
>  	phy-mode = "rgmii-id";
>  	phy-handle = <&phy1>;
> +        #address-cells = <1>;
> +        #size-cells = <0>;

I think this should go in a separate patch.

>  
> -	mdio {
> +	mdio@1 {

Ditto.

Many thanks,
Andrea

>  		reg = <0x1>;
>  		reset-gpios = <&rp1_gpio 32 GPIO_ACTIVE_LOW>;
>  		reset-delay-us = <5000>;
> -- 
> 2.51.0
>

Re: [RFC PATCH] arm64: broadcom: bcm2712: Rework rp1 overlay handling

Posted by Andrea della Porta 1 month, 3 weeks ago

Hi Rob,

On 14:58 Tue 09 Dec     , Andrea della Porta wrote:
> Hi Rob,
> sorry for the delay...
> 
> On 15:15 Mon 17 Nov     , Rob Herring (Arm) wrote:
> > It's a requirement that DT overlays be applied at build time in order to
> > validate them as overlays are not validated on their own.
> > 
> > Simply adding a build time target is possible, but it's also not desirable
> > to have targets which include the overlay contents and apply the same
> > overlay.
> > 
> > Rework the targets such that there are 2 overlays: the existing RP1 overlay
> > and the board specific configuration of the RP1 (bcm2712-rpi-5-b.dtso).
> > 
> > Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
> > ---
> > The missing applying of rp1.dtbo will soon be a warning[1].
> > 
> > The comment in bcm2712-rpi-5-b.dts(o) needs updating or removing. The RP1
> > driver or userspace handling of the overlay probably needs updating to
> > handle the 2 overlays. IIRC, I think we can apply overlays to overlays
> > which may be useful here. If not, adding that to the tools should be
> > possible.
> > 
> > [1] https://lore.kernel.org/all/20251114222759.4181152-1-robh@kernel.org/
> > ---
> >  arch/arm64/boot/dts/broadcom/Makefile                 | 10 ++++++++--
> >  ...m2712-d-rpi-5-b.dts => bcm2712-d-rpi-5-b-base.dts} |  2 +-
> >  .../{bcm2712-rpi-5-b.dts => bcm2712-rpi-5-b.dtso}     | 11 +++++------
> >  3 files changed, 14 insertions(+), 9 deletions(-)
> >  rename arch/arm64/boot/dts/broadcom/{bcm2712-d-rpi-5-b.dts => bcm2712-d-rpi-5-b-base.dts} (95%)
> >  rename arch/arm64/boot/dts/broadcom/{bcm2712-rpi-5-b.dts => bcm2712-rpi-5-b.dtso} (92%)
> > 
> > diff --git a/arch/arm64/boot/dts/broadcom/Makefile b/arch/arm64/boot/dts/broadcom/Makefile
> > index 83d45afc6588..4957edec9d9f 100644
> > --- a/arch/arm64/boot/dts/broadcom/Makefile
> > +++ b/arch/arm64/boot/dts/broadcom/Makefile
> > @@ -6,9 +6,9 @@ DTC_FLAGS := -@
> >  dtb-$(CONFIG_ARCH_BCM2835) += bcm2711-rpi-400.dtb \
> >  			      bcm2711-rpi-4-b.dtb \
> >  			      bcm2711-rpi-cm4-io.dtb \
> > -			      bcm2712-rpi-5-b.dtb \
> > +			      bcm2712-rpi-5-b.dtbo \
> >  			      bcm2712-rpi-5-b-ovl-rp1.dtb \
> > -			      bcm2712-d-rpi-5-b.dtb \
> > +			      bcm2712-d-rpi-5-b-base.dtb \
> >  			      bcm2837-rpi-2-b.dtb \
> >  			      bcm2837-rpi-3-a-plus.dtb \
> >  			      bcm2837-rpi-3-b.dtb \
> > @@ -17,6 +17,12 @@ dtb-$(CONFIG_ARCH_BCM2835) += bcm2711-rpi-400.dtb \
> >  			      bcm2837-rpi-zero-2-w.dtb \
> >  			      rp1.dtbo
> >  
> > +bcm2712-rpi-5-b-dtbs := bcm2712-rpi-5-b-ovl-rp1.dtb rp1.dtbo bcm2712-rpi-5-b.dtbo
> > +dtb-$(CONFIG_ARCH_BCM2835) += bcm2712-rpi-5-b.dtb
> > +
> > +bcm2712-d-rpi-5-b-dtbs := bcm2712-d-rpi-5-b-base.dtb rp1.dtbo bcm2712-rpi-5-b.dtbo
> > +dtb-$(CONFIG_ARCH_BCM2835) += bcm2712-d-rpi-5-b.dtb
> > +
> >  subdir-y	+= bcmbca
> >  subdir-y	+= northstar2
> >  subdir-y	+= stingray
> > diff --git a/arch/arm64/boot/dts/broadcom/bcm2712-d-rpi-5-b.dts b/arch/arm64/boot/dts/broadcom/bcm2712-d-rpi-5-b-base.dts
> > similarity index 95%
> > rename from arch/arm64/boot/dts/broadcom/bcm2712-d-rpi-5-b.dts
> > rename to arch/arm64/boot/dts/broadcom/bcm2712-d-rpi-5-b-base.dts
> > index 7de24d60bcd1..48a0ae118839 100644
> > --- a/arch/arm64/boot/dts/broadcom/bcm2712-d-rpi-5-b.dts
> > +++ b/arch/arm64/boot/dts/broadcom/bcm2712-d-rpi-5-b-base.dts
> > @@ -1,7 +1,7 @@
> >  // SPDX-License-Identifier: (GPL-2.0 OR MIT)
> >  /dts-v1/;
> >  
> > -#include "bcm2712-rpi-5-b.dts"
> > +#include "bcm2712-rpi-5-b-ovl-rp1.dts"
> >  
> >  &gio_aon {
> >  	brcm,gpio-bank-widths = <15 6>;
> > diff --git a/arch/arm64/boot/dts/broadcom/bcm2712-rpi-5-b.dts b/arch/arm64/boot/dts/broadcom/bcm2712-rpi-5-b.dtso
> > similarity index 92%
> > rename from arch/arm64/boot/dts/broadcom/bcm2712-rpi-5-b.dts
> > rename to arch/arm64/boot/dts/broadcom/bcm2712-rpi-5-b.dtso
> > index b8f256545022..89d099c00035 100644
> > --- a/arch/arm64/boot/dts/broadcom/bcm2712-rpi-5-b.dts
> > +++ b/arch/arm64/boot/dts/broadcom/bcm2712-rpi-5-b.dtso
> > @@ -15,19 +15,18 @@
> >   */
> >  
> >  /dts-v1/;
> > +/plugin/;
> >  
> > -#include "bcm2712-rpi-5-b-ovl-rp1.dts"
> > -
> > -&pcie2 {
> > -	#include "rp1-nexus.dtsi"
> > -};
> > +#include <dt-bindings/gpio/gpio.h>
> 
> Sounds reasonable to me, please let me have a full round of tests to check for
> any issue with the driver and I'll come back with feedback.

Just a heads up, since you've posted this new revision [1] and that I'm currently
reworking RP1 overlay (in order to drop it), I assume that this patch is no longer
relevant and I'll avoid testing it.

Thanks,
Andrea

[1] - https://lore.kernel.org/all/aUQA5IKqqsrElzKP@apocalypse/

> 
> >  
> >  &rp1_eth {
> >  	status = "okay";
> >  	phy-mode = "rgmii-id";
> >  	phy-handle = <&phy1>;
> > +        #address-cells = <1>;
> > +        #size-cells = <0>;
> 
> I think this should go in a separate patch.
> 
> >  
> > -	mdio {
> > +	mdio@1 {
> 
> Ditto.
> 
> Many thanks,
> Andrea
> 
> >  		reg = <0x1>;
> >  		reset-gpios = <&rp1_gpio 32 GPIO_ACTIVE_LOW>;
> >  		reset-delay-us = <5000>;
> > -- 
> > 2.51.0
> >

Re: [RFC PATCH] arm64: broadcom: bcm2712: Rework rp1 overlay handling

Posted by Krzysztof Kozlowski 2 months ago

On 17/11/2025 22:15, Rob Herring (Arm) wrote:
> It's a requirement that DT overlays be applied at build time in order to
> validate them as overlays are not validated on their own.
> 
> Simply adding a build time target is possible, but it's also not desirable
> to have targets which include the overlay contents and apply the same
> overlay.
> 
> Rework the targets such that there are 2 overlays: the existing RP1 overlay
> and the board specific configuration of the RP1 (bcm2712-rpi-5-b.dtso).
> 
> Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
> ---
> The missing applying of rp1.dtbo will soon be a warning[1].
> 
> The comment in bcm2712-rpi-5-b.dts(o) needs updating or removing. The RP1
> driver or userspace handling of the overlay probably needs updating to
> handle the 2 overlays. IIRC, I think we can apply overlays to overlays
> which may be useful here. If not, adding that to the tools should be
> possible.
> 
> [1] https://lore.kernel.org/all/20251114222759.4181152-1-robh@kernel.org/
> ---
>  arch/arm64/boot/dts/broadcom/Makefile                 | 10 ++++++++--
>  ...m2712-d-rpi-5-b.dts => bcm2712-d-rpi-5-b-base.dts} |  2 +-
>  .../{bcm2712-rpi-5-b.dts => bcm2712-rpi-5-b.dtso}     | 11 +++++------


So now Linus' tree has warnings. Can this be applied by anyone around
Broadcom and sent as fixes?


Best regards,
Krzysztof

Re: [RFC PATCH] arm64: broadcom: bcm2712: Rework rp1 overlay handling

Posted by Florian Fainelli 2 months ago

On 12/5/25 00:08, Krzysztof Kozlowski wrote:
> On 17/11/2025 22:15, Rob Herring (Arm) wrote:
>> It's a requirement that DT overlays be applied at build time in order to
>> validate them as overlays are not validated on their own.
>>
>> Simply adding a build time target is possible, but it's also not desirable
>> to have targets which include the overlay contents and apply the same
>> overlay.
>>
>> Rework the targets such that there are 2 overlays: the existing RP1 overlay
>> and the board specific configuration of the RP1 (bcm2712-rpi-5-b.dtso).
>>
>> Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
>> ---
>> The missing applying of rp1.dtbo will soon be a warning[1].
>>
>> The comment in bcm2712-rpi-5-b.dts(o) needs updating or removing. The RP1
>> driver or userspace handling of the overlay probably needs updating to
>> handle the 2 overlays. IIRC, I think we can apply overlays to overlays
>> which may be useful here. If not, adding that to the tools should be
>> possible.
>>
>> [1] https://lore.kernel.org/all/20251114222759.4181152-1-robh@kernel.org/
>> ---
>>   arch/arm64/boot/dts/broadcom/Makefile                 | 10 ++++++++--
>>   ...m2712-d-rpi-5-b.dts => bcm2712-d-rpi-5-b-base.dts} |  2 +-
>>   .../{bcm2712-rpi-5-b.dts => bcm2712-rpi-5-b.dtso}     | 11 +++++------
> 
> 
> So now Linus' tree has warnings. Can this be applied by anyone around
> Broadcom and sent as fixes?

It's an RFC and I was hoping to get Andrea to comment on this patch 
before applying.
-- 
Florian