Re: [PATCH V4 2/2] dt-bindings: mailbox: add doorbell support to ARM MHU

[Arnd Bergmann]

On Wed, Sep 16, 2020 at 11:39 AM Viresh Kumar <viresh.kumar@xxxxxxxxxx> wrote:
>
> From: Sudeep Holla <sudeep.holla@xxxxxxx>
>
> 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).
>
> Reviewed-by: Rob Herring <robh@xxxxxxxxxx>
> Signed-off-by: Sudeep Holla <sudeep.holla@xxxxxxx>
> Co-developed-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
> Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>

Acked-by: Arnd Bergmann <arnd@xxxxxxxx>