drtracing.org Git - deliverable/linux.git/blob

   1 Broadcom BCM6345-style Level 1 interrupt controller
   2
   3 This block is a first level interrupt controller that is typically connected
   4 directly to one of the HW INT lines on each CPU.
   5
   6 Key elements of the hardware design include:
   7
   8 - 32, 64 or 128 incoming level IRQ lines
   9
  10 - Most onchip peripherals are wired directly to an L1 input
  11
  12 - A separate instance of the register set for each CPU, allowing individual
  13   peripheral IRQs to be routed to any CPU
  14
  15 - Contains one or more enable/status word pairs per CPU
  16
  17 - No atomic set/clear operations
  18
  19 - No polarity/level/edge settings
  20
  21 - No FIFO or priority encoder logic; software is expected to read all
  22   2-4 status words to determine which IRQs are pending
  23
  24 Required properties:
  25
  26 - compatible: should be "brcm,bcm<soc>-l1-intc", "brcm,bcm6345-l1-intc"
  27 - reg: specifies the base physical address and size of the registers;
  28   the number of supported IRQs is inferred from the size argument
  29 - interrupt-controller: identifies the node as an interrupt controller
  30 - #interrupt-cells: specifies the number of cells needed to encode an interrupt
  31   source, should be 1.
  32 - interrupt-parent: specifies the phandle to the parent interrupt controller(s)
  33   this one is cascaded from
  34 - interrupts: specifies the interrupt line(s) in the interrupt-parent controller
  35   node; valid values depend on the type of parent interrupt controller
  36
  37 If multiple reg ranges and interrupt-parent entries are present on an SMP
  38 system, the driver will allow IRQ SMP affinity to be set up through the
  39 /proc/irq/ interface.  In the simplest possible configuration, only one
  40 reg range and one interrupt-parent is needed.
  41
  42 The driver operates in native CPU endian by default, there is no support for
  43 specifying an alternative endianness.
  44
  45 Example:
  46
  47 periph_intc: interrupt-controller@10000000 {
  48         compatible = "brcm,bcm63168-l1-intc", "brcm,bcm6345-l1-intc";
  49         reg = <0x10000020 0x20>,
  50               <0x10000040 0x20>;
  51
  52         interrupt-controller;
  53         #interrupt-cells = <1>;
  54
  55         interrupt-parent = <&cpu_intc>;
  56         interrupts = <2>, <3>;
  57 };