lkml.org 
[lkml]   [2020]   [Feb]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH 1/2] dt-bindings: arm: arm,scmi: add smc/hvc transports
    On 2020-02-07 11:00, Peng Fan wrote:
    >> Subject: Re: [PATCH 1/2] dt-bindings: arm: arm,scmi: add smc/hvc
    >> transports
    >>
    >> On 2020-02-07 10:47, Sudeep Holla wrote:
    >> > On Fri, Feb 07, 2020 at 10:08:36AM +0000, Marc Zyngier wrote:
    >> >> On 2020-02-06 13:01, peng.fan@nxp.com wrote:
    >> >> > From: Peng Fan <peng.fan@nxp.com>
    >> >> >
    >> >> > SCMI could use SMC/HVC as tranports, so add into devicetree binding
    >> >> > doc.
    >> >> >
    >> >> > Signed-off-by: Peng Fan <peng.fan@nxp.com>
    >> >> > ---
    >> >> > Documentation/devicetree/bindings/arm/arm,scmi.txt | 4 +++-
    >> >> > 1 file changed, 3 insertions(+), 1 deletion(-)
    >> >> >
    >> >> > diff --git a/Documentation/devicetree/bindings/arm/arm,scmi.txt
    >> >> > b/Documentation/devicetree/bindings/arm/arm,scmi.txt
    >> >> > index f493d69e6194..03cff8b55a93 100644
    >> >> > --- a/Documentation/devicetree/bindings/arm/arm,scmi.txt
    >> >> > +++ b/Documentation/devicetree/bindings/arm/arm,scmi.txt
    >> >> > @@ -14,7 +14,7 @@ Required properties:
    >> >> >
    >> >> > The scmi node with the following properties shall be under the
    >> >> > /firmware/ node.
    >> >> >
    >> >> > -- compatible : shall be "arm,scmi"
    >> >> > +- compatible : shall be "arm,scmi" or "arm,scmi-smc"
    >> >> > - mboxes: List of phandle and mailbox channel specifiers. It
    >> >> > should contain
    >> >> > exactly one or two mailboxes, one for transmitting messages("tx")
    >> >> > and another optional for receiving the notifications("rx") if
    >> >> > @@ -25,6 +25,8 @@ The scmi node with the following properties shall
    >> >> > be under the /firmware/ node.
    >> >> > protocol identifier for a given sub-node.
    >> >> > - #size-cells : should be '0' as 'reg' property doesn't have any size
    >> >> > associated with it.
    >> >> > +- arm,smc-id : SMC id required when using smc transports
    >> >> > +- arm,hvc-id : HVC id required when using hvc transports
    >> >> >
    >> >> > Optional properties:
    >> >>
    >> >> Not directly related to DT: Why do we need to distinguish between SMC
    >> >> and HVC?
    >> >
    >> > IIUC you want just one property to get the function ID ? Does that
    >> > align with what you are saying ? I wanted to ask the same question and
    >> > I see no need for 2 different properties.
    >>
    >> Exactly. Using SMC or HVC should come from the context, and there is
    >> zero
    >> value in having different different IDs, depending on the conduit.
    >>
    >> We *really* want SMC and HVC to behave the same way. Any attempt to
    >> make them different should just be NAKed.
    >
    > ok. Then just like psci node,
    > Add a "method" property for each protocol, and add "arm,func-id" to
    > indicate the ID.
    >
    > How about this?

    Or rather just a function ID, full stop. the conduit *MUST* be inherited
    from the PSCI context.

    M.
    --
    Jazz is not dead. It just smells funny...

    \
     
     \ /
      Last update: 2020-02-07 12:10    [W:3.844 / U:0.328 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site