diff options
Diffstat (limited to 'target/linux/bcm27xx/patches-5.4/950-0699-ARM-dts-bcm2711-Allow-40-bit-DMA-for-SPI.patch')
| -rw-r--r-- | target/linux/bcm27xx/patches-5.4/950-0699-ARM-dts-bcm2711-Allow-40-bit-DMA-for-SPI.patch | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/target/linux/bcm27xx/patches-5.4/950-0699-ARM-dts-bcm2711-Allow-40-bit-DMA-for-SPI.patch b/target/linux/bcm27xx/patches-5.4/950-0699-ARM-dts-bcm2711-Allow-40-bit-DMA-for-SPI.patch new file mode 100644 index 0000000000..ac6543fe4f --- /dev/null +++ b/target/linux/bcm27xx/patches-5.4/950-0699-ARM-dts-bcm2711-Allow-40-bit-DMA-for-SPI.patch @@ -0,0 +1,40 @@ +From 0dcafa8ab800d1f534bb0cb51cd02a082cf34be6 Mon Sep 17 00:00:00 2001 +From: Phil Elwell <phil@raspberrypi.com> +Date: Thu, 30 Apr 2020 12:43:05 +0100 +Subject: [PATCH] ARM: dts: bcm2711: Allow 40-bit DMA for SPI + +Add the spi_dma4 DT parameter to enable use of the 40-bit DMA channels +to drive SPI. Note that there are only 3-4 40-bit channels available, +and using this parameter claims 2 of them. + +Usage: dtparam=spi_dma4 + +Signed-off-by: Phil Elwell <phil@raspberrypi.com> +--- + arch/arm/boot/dts/bcm2711-rpi-4-b.dts | 2 ++ + arch/arm/boot/dts/overlays/README | 4 ++++ + 2 files changed, 6 insertions(+) + +--- a/arch/arm/boot/dts/bcm2711-rpi-4-b.dts ++++ b/arch/arm/boot/dts/bcm2711-rpi-4-b.dts +@@ -554,5 +554,7 @@ + eth_led0 = <&phy1>,"led-modes:0"; + eth_led1 = <&phy1>,"led-modes:4"; + ++ spi_dma4 = <&spi0>, "dmas:0=", <&dma40>, ++ <&spi0>, "dmas:8=", <&dma40>; + }; + }; +--- a/arch/arm/boot/dts/overlays/README ++++ b/arch/arm/boot/dts/overlays/README +@@ -159,6 +159,10 @@ Params: + spi Set to "on" to enable the spi interfaces + (default "off") + ++ spi_dma4 Use to enable 40-bit DMA on spi interfaces ++ (the assigned value doesn't matter) ++ (2711 only) ++ + random Set to "on" to enable the hardware random + number generator (default "on") + |