dt-bindings: dmaengine: nbpfaxi: Rename bindings documentation file

Rename the device tree bindings for renesas "Type-AXI" NBPFAXI* DMA
controllers from nbpfaxi.txt to renesas,nbpfaxi.txt.

This is part of an ongoing effort to name bindings documentation files for
Renesas IP blocks consistently, in line with the compat strings they
document.

Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Link: https://lore.kernel.org/r/20190819135244.18183-1-horms+renesas@verge.net.au
Signed-off-by: Vinod Koul <vkoul@kernel.org>

1 files changed, 69 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/dma/renesas,nbpfaxi.txt b/Documentation/devicetree/bindings/dma/renesas,nbpfaxi.txt
new file mode 100644
index 000000000000..d2e1e62e346a
--- /dev/null
+++ b/Documentation/devicetree/bindings/dma/renesas,nbpfaxi.txt
@@ -0,0 +1,69 @@
+* 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";