From 07455e4e4321129af0053c61191707ccf8289fc7 Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Mon, 26 Jun 2017 16:02:39 +0100 Subject: dt-bindings: mailbox: add support for mailbox client shared memory Many users of the mailbox controllers depend on the shared memory between the two end points to exchange the main data while using simple doorbell mechanism to alert the end points of the presence of a message. This patch defines device tree bindings to represent such shared memory in a generic way. Cc: Mark Rutland Acked-by: Rob Herring Signed-off-by: Sudeep Holla --- .../devicetree/bindings/mailbox/mailbox.txt | 28 ++++++++++++++++++++++ 1 file changed, 28 insertions(+) (limited to 'Documentation/devicetree/bindings/mailbox') diff --git a/Documentation/devicetree/bindings/mailbox/mailbox.txt b/Documentation/devicetree/bindings/mailbox/mailbox.txt index be05b9746c69..af8ecee2ac68 100644 --- a/Documentation/devicetree/bindings/mailbox/mailbox.txt +++ b/Documentation/devicetree/bindings/mailbox/mailbox.txt @@ -23,6 +23,11 @@ Required property: Optional property: - mbox-names: List of identifier strings for each mailbox channel. +- shmem : List of phandle pointing to the shared memory(SHM) area between the + users of these mailboxes for IPC, one for each mailbox. This shared + memory can be part of any memory reserved for the purpose of this + communication between the mailbox client and the remote. + Example: pwr_cntrl: power { @@ -30,3 +35,26 @@ Example: mbox-names = "pwr-ctrl", "rpc"; mboxes = <&mailbox 0 &mailbox 1>; }; + +Example with shared memory(shmem): + + sram: sram@50000000 { + compatible = "mmio-sram"; + reg = <0x50000000 0x10000>; + + #address-cells = <1>; + #size-cells = <1>; + ranges = <0 0x50000000 0x10000>; + + cl_shmem: shmem@0 { + compatible = "client-shmem"; + reg = <0x0 0x200>; + }; + }; + + client@2e000000 { + ... + mboxes = <&mailbox 0>; + shmem = <&cl_shmem>; + .. + }; -- cgit v1.2.3