This patchset changes the generation of the Raspberry Pi devices DTB
files to improve the support for out-of-tree device-tree overlays, like
it has recently been done for the Nvidia SoCs.
I personally only need that for arm64, but I have added a similar patch
to do the same on arm.
Aurelien Jarno (2):
arm64: dts: broadcom: Enable device-tree overlay support for RPi
devices
arm: dts: Enable device-tree overlay support for RPi devices
arch/arm/boot/dts/Makefile | 18 ++++++++++++++++++
arch/arm64/boot/dts/broadcom/Makefile | 11 +++++++++++
2 files changed, 29 insertions(+)
--
2.34.1
Add the '-@' DTC option for the Raspberry Pi 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 Rasbperry Pi devices are well known for their GPIO header, that
allow various "HATs" or other modules do 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 ~40%. For example, with v5.17 increase in size is as follows:
bcm2711-rpi-400.dtb 26481 -> 36830 bytes
bcm2711-rpi-4-b.dtb 26537 -> 36886 bytes
bcm2711-rpi-cm4-io.dtb 26426 -> 36945 bytes
bcm2835-rpi-a.dtb 12641 -> 17852 bytes
bcm2835-rpi-a-plus.dtb 12765 -> 17976 bytes
bcm2835-rpi-b.dtb 12763 -> 17998 bytes
bcm2835-rpi-b-plus.dtb 12979 -> 18263 bytes
bcm2835-rpi-b-rev2.dtb 12847 -> 18131 bytes
bcm2835-rpi-cm1-io1.dtb 12839 -> 18113 bytes
bcm2835-rpi-zero.dtb 12681 -> 17924 bytes
bcm2835-rpi-zero-w.dtb 13135 -> 18430 bytes
bcm2836-rpi-2-b.dtb 13687 -> 19255 bytes
bcm2837-rpi-3-a-plus.dtb 14133 -> 19740 bytes
bcm2837-rpi-3-b.dtb 14310 -> 20006 bytes
bcm2837-rpi-3-b-plus.dtb 14670 -> 20474 bytes
bcm2837-rpi-cm3-io3.dtb 13680 -> 19266 bytes
Signed-off-by: Aurelien Jarno <[email protected]>
---
arch/arm/boot/dts/Makefile | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)
diff --git a/arch/arm/boot/dts/Makefile b/arch/arm/boot/dts/Makefile
index 7c16f8a2b738..85644149de44 100644
--- a/arch/arm/boot/dts/Makefile
+++ b/arch/arm/boot/dts/Makefile
@@ -81,6 +81,24 @@ dtb-$(CONFIG_SOC_SAMA7G5) += \
at91-sama7g5ek.dtb
dtb-$(CONFIG_ARCH_AXXIA) += \
axm5516-amarillo.dtb
+# Enables support for device-tree overlays
+DTC_FLAGS_bcm2835-rpi-b := -@
+DTC_FLAGS_bcm2835-rpi-a := -@
+DTC_FLAGS_bcm2835-rpi-b-rev2 := -@
+DTC_FLAGS_bcm2835-rpi-b-plus := -@
+DTC_FLAGS_bcm2835-rpi-a-plus := -@
+DTC_FLAGS_bcm2835-rpi-cm1-io1 := -@
+DTC_FLAGS_bcm2836-rpi-2-b := -@
+DTC_FLAGS_bcm2837-rpi-3-a-plus := -@
+DTC_FLAGS_bcm2837-rpi-3-b := -@
+DTC_FLAGS_bcm2837-rpi-3-b-plus := -@
+DTC_FLAGS_bcm2837-rpi-cm3-io3 := -@
+DTC_FLAGS_bcm2837-rpi-zero-2-w := -@
+DTC_FLAGS_bcm2711-rpi-400 := -@
+DTC_FLAGS_bcm2711-rpi-4-b := -@
+DTC_FLAGS_bcm2711-rpi-cm4-io := -@
+DTC_FLAGS_bcm2835-rpi-zero := -@
+DTC_FLAGS_bcm2835-rpi-zero-w := -@
dtb-$(CONFIG_ARCH_BCM2835) += \
bcm2835-rpi-b.dtb \
bcm2835-rpi-a.dtb \
--
2.34.1
Add the '-@' DTC option for the Raspberry Pi devices. This option
populates the '__symbols__' node that contains all the necessary symbols
for supporting device-tree overlays (for instance from the firmware or
the bootloader) on these devices.
The Rasbperry Pi devices are well known for their GPIO header, that
allow various "HATs" or other modules do be connected and this enables
users to create out-of-tree device-tree overlays for these modules.
Please note that this change does increase the size of the resulting DTB
by ~40%. For example, with v5.17 increase in size is as follows:
bcm2711-rpi-400.dtb 26481 -> 36830 bytes
bcm2711-rpi-4-b.dtb 26537 -> 36886 bytes
bcm2711-rpi-cm4-io.dtb 26426 -> 36945 bytes
bcm2837-rpi-3-a-plus.dtb 14133 -> 19740 bytes
bcm2837-rpi-3-b.dtb 14310 -> 20006 bytes
bcm2837-rpi-3-b-plus.dtb 14670 -> 20474 bytes
bcm2837-rpi-cm3-io3.dtb 13680 -> 19266 bytes
Signed-off-by: Aurelien Jarno <[email protected]>
---
arch/arm64/boot/dts/broadcom/Makefile | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/arch/arm64/boot/dts/broadcom/Makefile b/arch/arm64/boot/dts/broadcom/Makefile
index 5082fcd1fea5..0aa8ee2afdd5 100644
--- a/arch/arm64/boot/dts/broadcom/Makefile
+++ b/arch/arm64/boot/dts/broadcom/Makefile
@@ -1,4 +1,15 @@
# SPDX-License-Identifier: GPL-2.0
+
+# Enables support for device-tree overlays
+DTC_FLAGS_bcm2711-rpi-400 := -@
+DTC_FLAGS_bcm2711-rpi-4-b := -@
+DTC_FLAGS_bcm2711-rpi-cm4-io := -@
+DTC_FLAGS_bcm2837-rpi-3-a-plus := -@
+DTC_FLAGS_bcm2837-rpi-3-b := -@
+DTC_FLAGS_bcm2837-rpi-3-b-plus := -@
+DTC_FLAGS_bcm2837-rpi-cm3-io3 := -@
+DTC_FLAGS_bcm2837-rpi-zero-2-w := -@
+
dtb-$(CONFIG_ARCH_BCM2835) += bcm2711-rpi-400.dtb \
bcm2711-rpi-4-b.dtb \
bcm2711-rpi-cm4-io.dtb \
--
2.34.1
Hello,
On Mon, Apr 11, 2022 at 12:59:38AM +0200, Aurelien Jarno wrote:
> This patchset changes the generation of the Raspberry Pi devices DTB
> files to improve the support for out-of-tree device-tree overlays, like
> it has recently been done for the Nvidia SoCs.
>
> I personally only need that for arm64, but I have added a similar patch
> to do the same on arm.
>
> Aurelien Jarno (2):
> arm64: dts: broadcom: Enable device-tree overlay support for RPi
> devices
> arm: dts: Enable device-tree overlay support for RPi devices
I like these changes,
Acked-by: Uwe Kleine-K?nig <[email protected]>
Given there was no feedback for >1 year now, I wonder if there are good
reasons against this change, or it just fell through the cracks?!
Best regards
Uwe
--
Pengutronix e.K. | Uwe Kleine-K?nig |
Industrial Linux Solutions | https://www.pengutronix.de/ |
Hello,
[expanded Cc: to include William Zhang and Florian Fainelli]
On Mon, Apr 11, 2022 at 12:59:39AM +0200, Aurelien Jarno wrote:
> Add the '-@' DTC option for the Raspberry Pi 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 Rasbperry Pi devices are well known for their GPIO header, that
> allow various "HATs" or other modules do 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 ~40%. For example, with v5.17 increase in size is as follows:
>
> bcm2711-rpi-400.dtb 26481 -> 36830 bytes
> bcm2711-rpi-4-b.dtb 26537 -> 36886 bytes
> bcm2711-rpi-cm4-io.dtb 26426 -> 36945 bytes
> bcm2837-rpi-3-a-plus.dtb 14133 -> 19740 bytes
> bcm2837-rpi-3-b.dtb 14310 -> 20006 bytes
> bcm2837-rpi-3-b-plus.dtb 14670 -> 20474 bytes
> bcm2837-rpi-cm3-io3.dtb 13680 -> 19266 bytes
>
> Signed-off-by: Aurelien Jarno <[email protected]>
> ---
> arch/arm64/boot/dts/broadcom/Makefile | 11 +++++++++++
> 1 file changed, 11 insertions(+)
>
> diff --git a/arch/arm64/boot/dts/broadcom/Makefile b/arch/arm64/boot/dts/broadcom/Makefile
> index 5082fcd1fea5..0aa8ee2afdd5 100644
> --- a/arch/arm64/boot/dts/broadcom/Makefile
> +++ b/arch/arm64/boot/dts/broadcom/Makefile
> @@ -1,4 +1,15 @@
> # SPDX-License-Identifier: GPL-2.0
> +
> +# Enables support for device-tree overlays
> +DTC_FLAGS_bcm2711-rpi-400 := -@
> +DTC_FLAGS_bcm2711-rpi-4-b := -@
> +DTC_FLAGS_bcm2711-rpi-cm4-io := -@
> +DTC_FLAGS_bcm2837-rpi-3-a-plus := -@
> +DTC_FLAGS_bcm2837-rpi-3-b := -@
> +DTC_FLAGS_bcm2837-rpi-3-b-plus := -@
> +DTC_FLAGS_bcm2837-rpi-cm3-io3 := -@
> +DTC_FLAGS_bcm2837-rpi-zero-2-w := -@
Instead of setting these all explicitly a single
DTC_FLAGS := -@
would work, too, without changing how the dts in subdirs are compiled.
IMHO this would be suiteable for arch/arm64/boot/dts/broadcom.
Best regards
Uwe
--
Pengutronix e.K. | Uwe Kleine-K?nig |
Industrial Linux Solutions | https://www.pengutronix.de/ |