xref: /freebsd/sys/contrib/device-tree/Bindings/dma/brcm,bcm2835-dma.yaml (revision a90b9d0159070121c221b966469c3e36d912bf82) 
1# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2%YAML 1.2
3---
4$id: http://devicetree.org/schemas/dma/brcm,bcm2835-dma.yaml#
5$schema: http://devicetree.org/meta-schemas/core.yaml#
6
7title: BCM2835 DMA controller
8
9maintainers:
10  - Nicolas Saenz Julienne <nsaenz@kernel.org>
11
12description:
13  The BCM2835 DMA controller has 16 channels in total. Only the lower
14  13 channels have an associated IRQ. Some arbitrary channels are used by the
15  VideoCore firmware (1,3,6,7 in the current firmware version). The channels
16  0, 2 and 3 have special functionality and should not be used by the driver.
17
18allOf:
19  - $ref: dma-controller.yaml#
20
21properties:
22  compatible:
23    const: brcm,bcm2835-dma
24
25  reg:
26    maxItems: 1
27
28  interrupts:
29    description:
30      Should contain the DMA interrupts associated to the DMA channels in
31      ascending order.
32    minItems: 1
33    maxItems: 16
34
35  interrupt-names:
36    minItems: 1
37    maxItems: 16
38
39  '#dma-cells':
40    description: The single cell represents the DREQ number.
41    const: 1
42
43  brcm,dma-channel-mask:
44    $ref: /schemas/types.yaml#/definitions/uint32
45    description:
46      Bitmask of available DMA channels in ascending order that are
47      not reserved by firmware and are available to the
48      kernel. i.e. first channel corresponds to LSB.
49
50unevaluatedProperties: false
51
52required:
53  - compatible
54  - reg
55  - interrupts
56  - "#dma-cells"
57  - brcm,dma-channel-mask
58
59examples:
60  - |
61    dma-controller@7e007000 {
62      compatible = "brcm,bcm2835-dma";
63      reg = <0x7e007000 0xf00>;
64      interrupts = <1 16>,
65                   <1 17>,
66                   <1 18>,
67                   <1 19>,
68                   <1 20>,
69                   <1 21>,
70                   <1 22>,
71                   <1 23>,
72                   <1 24>,
73                   <1 25>,
74                   <1 26>,
75                   /* dma channel 11-14 share one irq */
76                   <1 27>,
77                   <1 27>,
78                   <1 27>,
79                   <1 27>,
80                   /* unused shared irq for all channels */
81                   <1 28>;
82      interrupt-names = "dma0",
83                        "dma1",
84                        "dma2",
85                        "dma3",
86                        "dma4",
87                        "dma5",
88                        "dma6",
89                        "dma7",
90                        "dma8",
91                        "dma9",
92                        "dma10",
93                        "dma11",
94                        "dma12",
95                        "dma13",
96                        "dma14",
97                        "dma-shared-all";
98        #dma-cells = <1>;
99        brcm,dma-channel-mask = <0x7f35>;
100    };
101
102...
103