diff options
Diffstat (limited to '')
-rw-r--r-- | Documentation/devicetree/bindings/dma/st,stm32-mdma.yaml | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/dma/st,stm32-mdma.yaml b/Documentation/devicetree/bindings/dma/st,stm32-mdma.yaml new file mode 100644 index 000000000..00cfa3913 --- /dev/null +++ b/Documentation/devicetree/bindings/dma/st,stm32-mdma.yaml @@ -0,0 +1,106 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/dma/st,stm32-mdma.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: STMicroelectronics STM32 MDMA Controller bindings + +description: | + The STM32 MDMA is a general-purpose direct memory access controller capable of + supporting 64 independent DMA channels with 256 HW requests. + DMA clients connected to the STM32 MDMA controller must use the format + described in the dma.txt file, using a five-cell specifier for each channel: + a phandle to the MDMA controller plus the following five integer cells: + 1. The request line number + 2. The priority level + 0x0: Low + 0x1: Medium + 0x2: High + 0x3: Very high + 3. A 32bit mask specifying the DMA channel configuration + -bit 0-1: Source increment mode + 0x0: Source address pointer is fixed + 0x2: Source address pointer is incremented after each data transfer + 0x3: Source address pointer is decremented after each data transfer + -bit 2-3: Destination increment mode + 0x0: Destination address pointer is fixed + 0x2: Destination address pointer is incremented after each data transfer + 0x3: Destination address pointer is decremented after each data transfer + -bit 8-9: Source increment offset size + 0x0: byte (8bit) + 0x1: half-word (16bit) + 0x2: word (32bit) + 0x3: double-word (64bit) + -bit 10-11: Destination increment offset size + 0x0: byte (8bit) + 0x1: half-word (16bit) + 0x2: word (32bit) + 0x3: double-word (64bit) + -bit 25-18: The number of bytes to be transferred in a single transfer + (min = 1 byte, max = 128 bytes) + -bit 29:28: Trigger Mode + 0x00: Each MDMA request triggers a buffer transfer (max 128 bytes) + 0x1: Each MDMA request triggers a block transfer (max 64K bytes) + 0x2: Each MDMA request triggers a repeated block transfer + 0x3: Each MDMA request triggers a linked list transfer + 4. A 32bit value specifying the register to be used to acknowledge the request + if no HW ack signal is used by the MDMA client + 5. A 32bit mask specifying the value to be written to acknowledge the request + if no HW ack signal is used by the MDMA client + +maintainers: + - Amelie Delaunay <amelie.delaunay@foss.st.com> + +allOf: + - $ref: "dma-controller.yaml#" + +properties: + "#dma-cells": + const: 5 + + compatible: + const: st,stm32h7-mdma + + reg: + maxItems: 1 + + clocks: + maxItems: 1 + + interrupts: + maxItems: 1 + + resets: + maxItems: 1 + + st,ahb-addr-masks: + $ref: /schemas/types.yaml#/definitions/uint32-array + description: Array of u32 mask to list memory devices addressed via AHB bus. + +required: + - compatible + - reg + - clocks + - interrupts + +unevaluatedProperties: false + +examples: + - | + #include <dt-bindings/interrupt-controller/arm-gic.h> + #include <dt-bindings/clock/stm32mp1-clks.h> + #include <dt-bindings/reset/stm32mp1-resets.h> + dma-controller@52000000 { + compatible = "st,stm32h7-mdma"; + reg = <0x52000000 0x1000>; + interrupts = <122>; + clocks = <&timer_clk>; + resets = <&rcc 992>; + #dma-cells = <5>; + dma-channels = <16>; + dma-requests = <32>; + st,ahb-addr-masks = <0x20000000>, <0x00000000>; + }; + +... |