Documentation/devicetree/bindings/mailbox/xlnx,zynqmp-ipi-mailbox.txt

   1 Xilinx IPI Mailbox Controller
   2 ========================================
   3
   4 The Xilinx IPI(Inter Processor Interrupt) mailbox controller is to manage
   5 messaging between two Xilinx Zynq UltraScale+ MPSoC IPI agents. Each IPI
   6 agent owns registers used for notification and buffers for message.
   7
   8                +-------------------------------------+
   9                | Xilinx ZynqMP IPI Controller        |
  10                +-------------------------------------+
  11     +--------------------------------------------------+
  12 ATF                    |                     |
  13                        |                     |
  14                        |                     |
  15     +--------------------------+             |
  16                        |                     |
  17                        |                     |
  18     +--------------------------------------------------+
  19             +------------------------------------------+
  20             |  +----------------+   +----------------+ |
  21 Hardware    |  |  IPI Agent     |   |  IPI Buffers   | |
  22             |  |  Registers     |   |                | |
  23             |  |                |   |                | |
  24             |  +----------------+   +----------------+ |
  25             |                                          |
  26             | Xilinx IPI Agent Block                   |
  27             +------------------------------------------+
  28
  29
  30 Controller Device Node:
  31 ===========================
  32 Required properties:
  33 --------------------
  34 IPI agent node:
  35 - compatible:           Shall be: "xlnx,zynqmp-ipi-mailbox"
  36 - interrupt-parent:     Phandle for the interrupt controller
  37 - interrupts:           Interrupt information corresponding to the
  38                         interrupt-names property.
  39 - xlnx,ipi-id:          local Xilinx IPI agent ID
  40 - #address-cells:       number of address cells of internal IPI mailbox nodes
  41 - #size-cells:          number of size cells of internal IPI mailbox nodes
  42
  43 Internal IPI mailbox node:
  44 - reg:                  IPI buffers address ranges
  45 - reg-names:            Names of the reg resources. It should have:
  46                         * local_request_region
  47                           - IPI request msg buffer written by local and read
  48                             by remote
  49                         * local_response_region
  50                           - IPI response msg buffer written by local and read
  51                             by remote
  52                         * remote_request_region
  53                           - IPI request msg buffer written by remote and read
  54                             by local
  55                         * remote_response_region
  56                           - IPI response msg buffer written by remote and read
  57                             by local
  58 - #mbox-cells:          Shall be 1. It contains:
  59                         * tx(0) or rx(1) channel
  60 - xlnx,ipi-id:          remote Xilinx IPI agent ID of which the mailbox is
  61                         connected to.
  62
  63 Optional properties:
  64 --------------------
  65 - method:              The method of accessing the IPI agent registers.
  66                        Permitted values are: "smc" and "hvc". Default is
  67                        "smc".
  68
  69 Client Device Node:
  70 ===========================
  71 Required properties:
  72 --------------------
  73 - mboxes:               Standard property to specify a mailbox
  74                         (See ./mailbox.txt)
  75 - mbox-names:           List of identifier  strings for each mailbox
  76                         channel.
  77
  78 Example:
  79 ===========================
  80         zynqmp_ipi {
  81                 compatible = "xlnx,zynqmp-ipi-mailbox";
  82                 interrupt-parent = <&gic>;
  83                 interrupts = <0 29 4>;
  84                 xlnx,ipi-id = <0>;
  85                 #address-cells = <1>;
  86                 #size-cells = <1>;
  87                 ranges;
  88
  89                 /* APU<->RPU0 IPI mailbox controller */
  90                 ipi_mailbox_rpu0: mailbox@ff90400 {
  91                         reg = <0xff990400 0x20>,
  92                               <0xff990420 0x20>,
  93                               <0xff990080 0x20>,
  94                               <0xff9900a0 0x20>;
  95                         reg-names = "local_request_region",
  96                                     "local_response_region",
  97                                     "remote_request_region",
  98                                     "remote_response_region";
  99                         #mbox-cells = <1>;
 100                         xlnx,ipi-id = <1>;
 101                 };
 102                 /* APU<->RPU1 IPI mailbox controller */
 103                 ipi_mailbox_rpu1: mailbox@ff990440 {
 104                         reg = <0xff990440 0x20>,
 105                               <0xff990460 0x20>,
 106                               <0xff990280 0x20>,
 107                               <0xff9902a0 0x20>;
 108                         reg-names = "local_request_region",
 109                                     "local_response_region",
 110                                     "remote_request_region",
 111                                     "remote_response_region";
 112                         #mbox-cells = <1>;
 113                         xlnx,ipi-id = <2>;
 114                 };
 115         };
 116         rpu0 {
 117                 ...
 118                 mboxes = <&ipi_mailbox_rpu0 0>,
 119                          <&ipi_mailbox_rpu0 1>;
 120                 mbox-names = "tx", "rx";
 121         };
 122         rpu1 {
 123                 ...
 124                 mboxes = <&ipi_mailbox_rpu1 0>,
 125                          <&ipi_mailbox_rpu1 1>;
 126                 mbox-names = "tx", "rx";
 127         };