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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
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tree848558de17fb3008cdf4d861b01ac7781903ce39 /Documentation/devicetree/bindings/dma/st,stm32-dma.yaml
parentInitial commit. (diff)
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Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
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+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/dma/st,stm32-dma.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: STMicroelectronics STM32 DMA Controller bindings
+
+description: |
+ The STM32 DMA is a general-purpose direct memory access controller capable of
+ supporting 8 independent DMA channels. Each channel can have up to 8 requests.
+ DMA clients connected to the STM32 DMA controller must use the format
+ described in the dma.txt file, using a four-cell specifier for each
+ channel: a phandle to the DMA controller plus the following four integer cells:
+ 1. The channel id
+ 2. The request line number
+ 3. A 32bit mask specifying the DMA channel configuration which are device
+ dependent:
+ -bit 9: Peripheral Increment Address
+ 0x0: no address increment between transfers
+ 0x1: increment address between transfers
+ -bit 10: Memory Increment Address
+ 0x0: no address increment between transfers
+ 0x1: increment address between transfers
+ -bit 15: Peripheral Increment Offset Size
+ 0x0: offset size is linked to the peripheral bus width
+ 0x1: offset size is fixed to 4 (32-bit alignment)
+ -bit 16-17: Priority level
+ 0x0: low
+ 0x1: medium
+ 0x2: high
+ 0x3: very high
+ 4. A 32bit bitfield value specifying DMA features which are device dependent:
+ -bit 0-1: DMA FIFO threshold selection
+ 0x0: 1/4 full FIFO
+ 0x1: 1/2 full FIFO
+ 0x2: 3/4 full FIFO
+ 0x3: full FIFO
+ -bit 2: DMA direct mode
+ 0x0: FIFO mode with threshold selectable with bit 0-1
+ 0x1: Direct mode: each DMA request immediately initiates a transfer
+ from/to the memory, FIFO is bypassed.
+ -bit 4: alternative DMA request/acknowledge protocol
+ 0x0: Use standard DMA ACK management, where ACK signal is maintained
+ up to the removal of request and transfer completion
+ 0x1: Use alternative DMA ACK management, where ACK de-assertion does
+ not wait for the de-assertion of the REQuest, ACK is only managed
+ by transfer completion. This must only be used on channels
+ managing transfers for STM32 USART/UART.
+
+
+maintainers:
+ - Amelie Delaunay <amelie.delaunay@foss.st.com>
+
+allOf:
+ - $ref: "dma-controller.yaml#"
+
+properties:
+ "#dma-cells":
+ const: 4
+
+ compatible:
+ const: st,stm32-dma
+
+ reg:
+ maxItems: 1
+
+ clocks:
+ maxItems: 1
+
+ interrupts:
+ maxItems: 8
+ description: Should contain all of the per-channel DMA
+ interrupts in ascending order with respect to the
+ DMA channel index.
+
+ resets:
+ maxItems: 1
+
+ st,mem2mem:
+ $ref: /schemas/types.yaml#/definitions/flag
+ description: if defined, it indicates that the controller
+ supports memory-to-memory transfer
+
+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@40026400 {
+ compatible = "st,stm32-dma";
+ reg = <0x40026400 0x400>;
+ interrupts = <56>,
+ <57>,
+ <58>,
+ <59>,
+ <60>,
+ <68>,
+ <69>,
+ <70>;
+ clocks = <&clk_hclk>;
+ #dma-cells = <4>;
+ st,mem2mem;
+ resets = <&rcc 150>;
+ dma-requests = <8>;
+ };
+
+...