kernel/Documentation/devicetree/bindings/dma/img-mdc-dma.txt

   1 * IMG Multi-threaded DMA Controller (MDC)
   2
   3 Required properties:
   4 - compatible: Must be "img,pistachio-mdc-dma".
   5 - reg: Must contain the base address and length of the MDC registers.
   6 - interrupts: Must contain all the per-channel DMA interrupts.
   7 - clocks: Must contain an entry for each entry in clock-names.
   8   See ../clock/clock-bindings.txt for details.
   9 - clock-names: Must include the following entries:
  10   - sys: MDC system interface clock.
  11 - img,cr-periph: Must contain a phandle to the peripheral control syscon
  12   node which contains the DMA request to channel mapping registers.
  13 - img,max-burst-multiplier: Must be the maximum supported burst size multiplier.
  14   The maximum burst size is this value multiplied by the hardware-reported bus
  15   width.
  16 - #dma-cells: Must be 3:
  17   - The first cell is the peripheral's DMA request line.
  18   - The second cell is a bitmap specifying to which channels the DMA request
  19     line may be mapped (i.e. bit N set indicates channel N is usable).
  20   - The third cell is the thread ID to be used by the channel.
  21
  22 Optional properties:
  23 - dma-channels: Number of supported DMA channels, up to 32.  If not specified
  24   the number reported by the hardware is used.
  25
  26 Example:
  27
  28 mdc: dma-controller@18143000 {
  29         compatible = "img,pistachio-mdc-dma";
  30         reg = <0x18143000 0x1000>;
  31         interrupts = <GIC_SHARED 27 IRQ_TYPE_LEVEL_HIGH>,
  32                      <GIC_SHARED 28 IRQ_TYPE_LEVEL_HIGH>,
  33                      <GIC_SHARED 29 IRQ_TYPE_LEVEL_HIGH>,
  34                      <GIC_SHARED 30 IRQ_TYPE_LEVEL_HIGH>,
  35                      <GIC_SHARED 31 IRQ_TYPE_LEVEL_HIGH>,
  36                      <GIC_SHARED 32 IRQ_TYPE_LEVEL_HIGH>,
  37                      <GIC_SHARED 33 IRQ_TYPE_LEVEL_HIGH>,
  38                      <GIC_SHARED 34 IRQ_TYPE_LEVEL_HIGH>,
  39                      <GIC_SHARED 35 IRQ_TYPE_LEVEL_HIGH>,
  40                      <GIC_SHARED 36 IRQ_TYPE_LEVEL_HIGH>,
  41                      <GIC_SHARED 37 IRQ_TYPE_LEVEL_HIGH>,
  42                      <GIC_SHARED 38 IRQ_TYPE_LEVEL_HIGH>;
  43         clocks = <&system_clk>;
  44         clock-names = "sys";
  45
  46         img,max-burst-multiplier = <16>;
  47         img,cr-periph = <&cr_periph>;
  48
  49         #dma-cells = <3>;
  50 };
  51
  52 spi@18100f00 {
  53         ...
  54         dmas = <&mdc 9 0xffffffff 0>, <&mdc 10 0xffffffff 0>;
  55         dma-names = "tx", "rx";
  56         ...
  57 };