Hi Ramesh,
From: "ext Ramesh Gupta Guntha" <grgupta77@xxxxxxxxx>
Subject: Re: [PATCH 02/10] omap mailbox: add initial omap3 support
Date: Thu, 22 Jan 2009 10:42:52 +0530
> Hi Hiroshi,
>
>
> On 1/22/09, Hiroshi DOYU <Hiroshi.DOYU@xxxxxxxxx> wrote:
> > Hi Hari,
> >
> > From: "ext Kanigeri, Hari" <h-kanigeri2@xxxxxx>
> > Subject: RE: [PATCH 02/10] omap mailbox: add initial omap3 support
> > Date: Wed, 21 Jan 2009 14:02:05 -0600
> >
> > > Hi Doyu-san,
> > >
> > > Can we add the function to return number of messages in the mailbox ?
> >
> > Yes. I assume that you meant the number of h/w fifo.
> > It would be helpful if you explain the case where this API is used.
>
> This is to make sure that mail box fifo is not full before trying to
> write a new message, if it is full for any reason, one can wait for a
> while until fifo is empty.
In the current mailbox implementation, the (request)queue is provided
in order to avoid the situation where client/user has to wait until
fifo is available. And then, a kernel thread tries to put each request
into h/w fifo. If h/w fifo is full, it tries later again.
So I think that there's no need for client side to care about the
availability of h/w fifo, but there's a case that s/w queue isn't
avaiable because of the lack of memory, then client has to sleep or
try again. This is quite unlikely, though.
Hiroshi DOYU
--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
