diff options
Diffstat (limited to 'target/linux/bcm27xx/patches-5.4/950-0438-ARM-dts-bcm2711-fix-soc-s-node-dma-ranges.patch')
| -rw-r--r-- | target/linux/bcm27xx/patches-5.4/950-0438-ARM-dts-bcm2711-fix-soc-s-node-dma-ranges.patch | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/target/linux/bcm27xx/patches-5.4/950-0438-ARM-dts-bcm2711-fix-soc-s-node-dma-ranges.patch b/target/linux/bcm27xx/patches-5.4/950-0438-ARM-dts-bcm2711-fix-soc-s-node-dma-ranges.patch new file mode 100644 index 0000000000..ed0be9b9a3 --- /dev/null +++ b/target/linux/bcm27xx/patches-5.4/950-0438-ARM-dts-bcm2711-fix-soc-s-node-dma-ranges.patch @@ -0,0 +1,40 @@ +From 44d7ee4730fbe3c00aba0457489acd0b6e2937c9 Mon Sep 17 00:00:00 2001 +From: Nicolas Saenz Julienne <nsaenzjulienne@suse.de> +Date: Wed, 4 Dec 2019 13:56:33 +0100 +Subject: [PATCH] ARM: dts: bcm2711: fix soc's node dma-ranges + +Raspberry Pi's firmware has a feature to select how much memory to +reserve for its GPU called 'gpu_mem'. The possible values go from 16MB +to 944MB, with a default of 64MB. This memory resides in the topmost +part of the lower 1GB memory area and grows bigger expanding towards the +begging of memory. + +It turns out that with low 'gpu_mem' values (16MB and 32MB) the size of +the memory available to the system in the lower 1GB area can outgrow the +interconnect's dma-range as its size was selected based on the maximum +system memory available given the default gpu_mem configuration. This +makes that memory slice unavailable for DMA. And may cause nasty kernel +warnings if CMA happens to include it. + +Change soc's dma-ranges to really reflect it's HW limitation, which is +being able to only DMA to the lower 1GB area. + +Fixes: 7dbe8c62ceeb ("ARM: dts: Add minimal Raspberry Pi 4 support") +Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de> +Reviewed-by: Phil Elwell <phil@raspberrypi.org> +Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> +--- + arch/arm/boot/dts/bcm2711.dtsi | 2 +- + 1 file changed, 1 insertion(+), 1 deletion(-) + +--- a/arch/arm/boot/dts/bcm2711.dtsi ++++ b/arch/arm/boot/dts/bcm2711.dtsi +@@ -43,7 +43,7 @@ + <0x7c000000 0x0 0xfc000000 0x02000000>, + <0x40000000 0x0 0xff800000 0x00800000>; + /* Emulate a contiguous 30-bit address range for DMA */ +- dma-ranges = <0xc0000000 0x0 0x00000000 0x3c000000>; ++ dma-ranges = <0xc0000000 0x0 0x00000000 0x40000000>; + + /* + * This node is the provider for the enable-method for |