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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /Documentation/devicetree/bindings/dma/nbpfaxi.txt
parentInitial commit. (diff)
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Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
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+* Renesas "Type-AXI" NBPFAXI* DMA controllers
+
+* DMA controller
+
+Required properties
+
+- compatible: must be one of
+ "renesas,nbpfaxi64dmac1b4"
+ "renesas,nbpfaxi64dmac1b8"
+ "renesas,nbpfaxi64dmac1b16"
+ "renesas,nbpfaxi64dmac4b4"
+ "renesas,nbpfaxi64dmac4b8"
+ "renesas,nbpfaxi64dmac4b16"
+ "renesas,nbpfaxi64dmac8b4"
+ "renesas,nbpfaxi64dmac8b8"
+ "renesas,nbpfaxi64dmac8b16"
+- #dma-cells: must be 2: the first integer is a terminal number, to which this
+ slave is connected, the second one is flags. Flags is a bitmask
+ with the following bits defined:
+
+#define NBPF_SLAVE_RQ_HIGH 1
+#define NBPF_SLAVE_RQ_LOW 2
+#define NBPF_SLAVE_RQ_LEVEL 4
+
+Optional properties:
+- max-burst-mem-read: limit burst size for memory reads
+ (DMA_MEM_TO_MEM/DMA_MEM_TO_DEV) to this value, specified in bytes, rather
+ than using the maximum burst size allowed by the hardware's buffer size.
+- max-burst-mem-write: limit burst size for memory writes
+ (DMA_DEV_TO_MEM/DMA_MEM_TO_MEM) to this value, specified in bytes, rather
+ than using the maximum burst size allowed by the hardware's buffer size.
+ If both max-burst-mem-read and max-burst-mem-write are set, DMA_MEM_TO_MEM
+ will use the lower value.
+
+You can use dma-channels and dma-requests as described in dma.txt, although they
+won't be used, this information is derived from the compatibility string.
+
+Example:
+
+ dma: dma-controller@48000000 {
+ compatible = "renesas,nbpfaxi64dmac8b4";
+ reg = <0x48000000 0x400>;
+ interrupts = <0 12 0x4
+ 0 13 0x4
+ 0 14 0x4
+ 0 15 0x4
+ 0 16 0x4
+ 0 17 0x4
+ 0 18 0x4
+ 0 19 0x4>;
+ #dma-cells = <2>;
+ dma-channels = <8>;
+ dma-requests = <8>;
+ };
+
+* DMA client
+
+Required properties:
+
+dmas and dma-names are required, as described in dma.txt.
+
+Example:
+
+#include <dt-bindings/dma/nbpfaxi.h>
+
+...
+ dmas = <&dma 0 (NBPF_SLAVE_RQ_HIGH | NBPF_SLAVE_RQ_LEVEL)
+ &dma 1 (NBPF_SLAVE_RQ_HIGH | NBPF_SLAVE_RQ_LEVEL)>;
+ dma-names = "rx", "tx";