[PATCH v4 2/4] mailbox: Hi6220: add mailbox driver

Leo Yan leo.yan at linaro.org
Thu Oct 15 23:08:09 PDT 2015


On Fri, Oct 16, 2015 at 11:17:32AM +0530, Jassi Brar wrote:
> On Fri, Oct 16, 2015 at 10:59 AM, Leo Yan <leo.yan at linaro.org> wrote:
> > On Fri, Oct 16, 2015 at 10:43:00AM +0530, Jassi Brar wrote:
> >> On Mon, Oct 12, 2015 at 10:02 PM, Leo Yan <leo.yan at linaro.org> wrote:
> >>
> >> > +
> >> > +#define MBOX_CHAN_MAX                  32
> >> > +#define MBOX_CHAN_NUM                  2
> >> > +
> >> You mean the hardware has 32 channels but this driver can not manage
> >> more than 2 ?
> >>
> >> OR, there are 32 interfaces but only 2 physical 'floating' links, so
> >> no more than 2 interfaces can be active at any time?
> >
> > For the later case.
> Former is a s/w limitation and latter is h/w limitation. From what you
> write below, it seems former to be the case.

Sorry, i misunderstood the question. It's a s/w limitation.

> > Mailbox also can be used by other modules, such
> > like audio hifi; later need add links for them if want to enable
> > audio. But so far only uses first 2 channels.
> >
> You mean every time your platform needs another channel, you'll update
> the driver? Not sure about that. It should be simpler to assign which
> ever and as many channels as the client asks via DT.

For hi6220, every channel is fixed to specific purpose; so i can
register all of them in driver, such like hifi related channels;
Though i cannot test them currently, but this will avoid extra
efforts for enabling channels anymore, do you think this is okay?
Or you prefer to bind with DT?

Thanks,
Leo Yan



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