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authorNicolas Saenz Julienne <nsaenzjulienne@suse.de>2019-11-06 10:59:44 +0100
committerFlorian Fainelli <f.fainelli@gmail.com>2019-11-14 12:33:48 -0800
commitd98a8dbdaec628f5c993cc711ba9ab98fe909f0f (patch)
tree4cbfa3a45810e5e3da8cc50070781f44d8ba50d6 /arch
parent4c365e231bd1d3bbe2bdbc2a0c4e413ffb365b20 (diff)
downloadlinux-d98a8dbdaec628f5c993cc711ba9ab98fe909f0f.tar.gz
ARM: dts: bcm2711: force CMA into first GB of memory
arm64 places the CMA in ZONE_DMA32, which is not good enough for the
Raspberry Pi 4 since it contains peripherals that can only address the
first GB of memory. Explicitly place the CMA into that area.

Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Acked-by: Stefan Wahren <wahrenst@gmx.net>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Diffstat (limited to 'arch')
-rw-r--r--arch/arm/boot/dts/bcm2711.dtsi20
1 files changed, 20 insertions, 0 deletions
diff --git a/arch/arm/boot/dts/bcm2711.dtsi b/arch/arm/boot/dts/bcm2711.dtsi
index ac83dac2e6ba..34d24fe272e2 100644
--- a/arch/arm/boot/dts/bcm2711.dtsi
+++ b/arch/arm/boot/dts/bcm2711.dtsi
@@ -12,6 +12,26 @@
 
 	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: