Commit c5a1e537 authored by Nicolas Saenz Julienne's avatar Nicolas Saenz Julienne Committed by Florian Fainelli
Browse files

ARM: dts: bcm283x: Unify CMA configuration 



With the introduction of the Raspberry Pi 4 we were forced to explicitly
configure CMA's location, since arm64 defaults it into the ZONE_DMA32
memory area, which is not good enough to perform DMA operations on that
device. To bypass this limitation a dedicated CMA DT node was created,
explicitly indicating the acceptable memory range and size.

That said, compatibility between boards is a must on the Raspberry Pi
ecosystem so this creates a common CMA DT node so as for DT overlays to
be able to update CMA's properties regardless of the board being used.

Signed-off-by: default avatarNicolas Saenz Julienne <nsaenzjulienne@suse.de>
Reviewed-by: default avatarPhil Elwell <phil@raspberrypi.org>
Signed-off-by: default avatarFlorian Fainelli <f.fainelli@gmail.com>
parent 0100f76d

arch/arm/boot/dts/bcm2711.dtsi

+13 −20
Original line number Diff line number Diff line
@@ -12,26 +12,6 @@ 


	interrupt-parent = <&gicv2>;



	reserved-memory {

		#address-cells = <2>;

		#size-cells = <1>;

		ranges;



		/*

		 * arm64 reserves the CMA by default somewhere in ZONE_DMA32,

		 * that's not good enough for the BCM2711 as some devices can

		 * only address the lower 1G of memory (ZONE_DMA).

		 */

		linux,cma {

			compatible = "shared-dma-pool";

			size = <0x2000000>; /* 32MB */

			alloc-ranges = <0x0 0x00000000 0x40000000>;

			reusable;

			linux,cma-default;

		};

	};





	soc {

		/*

		 * Defined ranges:
@@ -826,6 +806,19 @@ 
	};

};



&rmem {

	#address-cells = <2>;

};



&cma {

	/*

	 * arm64 reserves the CMA by default somewhere in ZONE_DMA32,

	 * that's not good enough for the BCM2711 as some devices can

	 * only address the lower 1G of memory (ZONE_DMA).

	 */

	alloc-ranges = <0x0 0x00000000 0x40000000>;

};



&i2c0 {

	compatible = "brcm,bcm2711-i2c", "brcm,bcm2835-i2c";

	interrupts = <GIC_SPI 117 IRQ_TYPE_LEVEL_HIGH>;

arch/arm/boot/dts/bcm283x.dtsi

+13 −0
Original line number Diff line number Diff line
@@ -30,6 +30,19 @@ 
		stdout-path = "serial0:115200n8";

	};



	rmem: reserved-memory {

		#address-cells = <1>;

		#size-cells = <1>;

		ranges;



		cma: linux,cma {

			compatible = "shared-dma-pool";

			size = <0x4000000>; /* 64MB */

			reusable;

			linux,cma-default;

		};

	};



	thermal-zones {

		cpu_thermal: cpu-thermal {

			polling-delay-passive = <0>;

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