[PATCH V3 2/2] dt-bindings: mailbox: add doorbell support to ARM MHU

Rob Herring robh at kernel.org
Tue Sep 15 15:40:38 EDT 2020

On Thu, 10 Sep 2020 15:25:19 +0530, Viresh Kumar wrote:
> From: Sudeep Holla <sudeep.holla at arm.com>
> The ARM MHU's reference manual states following:
> "The MHU drives the signal using a 32-bit register, with all 32 bits
> logically ORed together. The MHU provides a set of registers to enable
> software to set, clear, and check the status of each of the bits of this
> register independently.  The use of 32 bits for each interrupt line
> enables software to provide more information about the source of the
> interrupt. For example, each bit of the register can be associated with
> a type of event that can contribute to raising the interrupt."
> This patch thus extends the MHU controller's DT binding to add support
> for doorbell mode.
> Though the same MHU hardware controller is used in the two modes, A new
> compatible string is added here to represent the combination of the MHU
> hardware and the firmware sitting on the other side (which expects each
> bit to represent a different signal now).
> Signed-off-by: Sudeep Holla <sudeep.holla at arm.com>
> Co-developed-by: Viresh Kumar <viresh.kumar at linaro.org>
> Signed-off-by: Viresh Kumar <viresh.kumar at linaro.org>
> ---
> V3: Update the json schema and fix number of interrupt lines.
>  .../devicetree/bindings/mailbox/arm,mhu.yaml  | 60 +++++++++++++++++--
>  1 file changed, 54 insertions(+), 6 deletions(-)

Reviewed-by: Rob Herring <robh at kernel.org>

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