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torvalds
GitHub Repository: torvalds/linux
 Path: blob/master/Documentation/devicetree/bindings/dma/brcm,bcm2835-dma.yaml
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# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)

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%YAML 1.2

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---

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$id: http://devicetree.org/schemas/dma/brcm,bcm2835-dma.yaml#

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$schema: http://devicetree.org/meta-schemas/core.yaml#

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title: BCM2835 DMA controller

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maintainers:

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  - Nicolas Saenz Julienne <nsaenz@kernel.org>

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description:

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  The BCM2835 DMA controller has 16 channels in total. Only the lower

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  13 channels have an associated IRQ. Some arbitrary channels are used by the

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  VideoCore firmware (1,3,6,7 in the current firmware version). The channels

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  0, 2 and 3 have special functionality and should not be used by the driver.

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allOf:

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  - $ref: dma-controller.yaml#

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properties:

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  compatible:

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    const: brcm,bcm2835-dma

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  reg:

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    maxItems: 1

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  interrupts:

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    description:

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      Should contain the DMA interrupts associated to the DMA channels in

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      ascending order.

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    minItems: 1

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    maxItems: 16

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  interrupt-names:

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    minItems: 1

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    maxItems: 16

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  '#dma-cells':

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    description: The single cell represents the DREQ number.

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    const: 1

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  brcm,dma-channel-mask:

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    $ref: /schemas/types.yaml#/definitions/uint32

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    description:

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      Bitmask of available DMA channels in ascending order that are

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      not reserved by firmware and are available to the

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      kernel. i.e. first channel corresponds to LSB.

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unevaluatedProperties: false

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required:

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  - compatible

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  - reg

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  - interrupts

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  - "#dma-cells"

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  - brcm,dma-channel-mask

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examples:

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  - |

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    dma-controller@7e007000 {

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      compatible = "brcm,bcm2835-dma";

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      reg = <0x7e007000 0xf00>;

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      interrupts = <1 16>,

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                   <1 17>,

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                   <1 18>,

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                   <1 19>,

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                   <1 20>,

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                   <1 21>,

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                   <1 22>,

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                   <1 23>,

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                   <1 24>,

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                   <1 25>,

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                   <1 26>,

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                   /* dma channel 11-14 share one irq */

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                   <1 27>,

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                   <1 27>,

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                   <1 27>,

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                   <1 27>,

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                   /* unused shared irq for all channels */

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                   <1 28>;

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      interrupt-names = "dma0",

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                        "dma1",

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                        "dma2",

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                        "dma3",

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                        "dma4",

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                        "dma5",

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                        "dma6",

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                        "dma7",

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                        "dma8",

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                        "dma9",

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                        "dma10",

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                        "dma11",

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                        "dma12",

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                        "dma13",

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                        "dma14",

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                        "dma-shared-all";

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        #dma-cells = <1>;

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        brcm,dma-channel-mask = <0x7f35>;

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    };

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...

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