Commit dac2b98e authored by Harini T's avatar Harini T Committed by Jassi Brar
Browse files

dt-bindings: mailbox: xlnx,zynqmp-ipi-mailbox: Document msg region requirement 



Add description clarifying that for Versal IPI mailboxes, both host and
remote agents must have the "msg" register region defined for successful
message passing. Without both, only notification-based communication
works.

Signed-off-by: default avatarHarini T <harini.t@amd.com>
Acked-by: default avatarRob Herring (Arm) <robh@kernel.org>
Signed-off-by: default avatarJassi Brar <jassisinghbrar@gmail.com>
parent 6acf50c7

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

+11 −0
Original line number Diff line number Diff line
@@ -11,6 +11,17 @@ description: | 
  messaging between two Xilinx Zynq UltraScale+ MPSoC IPI agents. Each IPI

  agent owns registers used for notification and buffers for message.



  For Versal devices, there are two types of IPI channels:

    - Buffered channels: Support message passing and require the "msg"

    register region to be present on both the host and remote IPI agents.

    - Buffer-less channels: Support notification only and do not require the

    "msg" register region. For these channels, the "msg" region should be

    omitted.



  For message passing, both the host and remote IPI agents must define the "msg"

  register region. If either agent omits the "msg" region, only notification

  based communication is possible.



               +-------------------------------------+

               | Xilinx ZynqMP IPI Controller        |

               +-------------------------------------+