From mboxrd@z Thu Jan 1 00:00:00 1970 From: Laurent Pinchart Date: Tue, 30 Sep 2014 10:48:27 +0000 Subject: Re: [PATCH] ARM: shmobile: r8a7790: switch from scif to scifa Message-Id: <1585108.kaX7ZqOH2z@avalon> List-Id: References: <1410883837-5611-1-git-send-email-wsa@the-dreams.de> In-Reply-To: <1410883837-5611-1-git-send-email-wsa@the-dreams.de> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-sh@vger.kernel.org Hi Geert, On Tuesday 30 September 2014 12:44:59 Geert Uytterhoeven wrote: > On Tue, Sep 30, 2014 at 12:40 PM, Laurent Pinchart wrote: > > On Tuesday 30 September 2014 13:30:29 Simon Horman wrote: > >> On Fri, Sep 19, 2014 at 12:28:28PM +0900, Simon Horman wrote: > >>> On Thu, Sep 18, 2014 at 10:57:12AM +0300, Laurent Pinchart wrote: > >>>> On Thursday 18 September 2014 08:55:43 Simon Horman wrote: > >>>>> On Wed, Sep 17, 2014 at 05:40:07PM +0300, Laurent Pinchart wrote: > >>>>>> On Tuesday 16 September 2014 18:10:37 Wolfram Sang wrote: > >>>>>>> From: Wolfram Sang > >>>>>>> > >>>>>>> SCIF and SCIFA can be plexed onto the same wires on Lager board. > >>>>>>> The datasheet also describes the wires as SCIFA. So, to make use > >>>>>>> of the bigger FIFOs switch to SCIFA instead. > >>>>>>> > >>>>>>> Signed-off-by: Wolfram Sang > >>>>>>> --- > >>>>>>> > >>>>>>> Currently, I use this patch to check if the DMA RX issue is the > >> >>>>> same on SCIF and SCIFA (yes, it is). However, I still think it > >>>>>>> makes sense to use the bigger FIFOs. I will check this next week > >>>>>>> with Bastian's FIFO patches. Until then, I send this as RFC to > >>>>>>> collect opinions speaking for/against this change. > >>>>>> > >>>>>> I have nothing against this change, but I believe the aliases should > >>>>>> now be serial0 and serial1 to match the legacy code (OK, that's a > >>>>>> lame excuse, we all know that I just want to change the aliases > >>>>>> ;-)). > >>>>> > >>>>> Thanks Laurent, I think its probably time we had that conversation > >>>>> again. But I think that change can be done (or not ^) separately to > >>>>> this change. > >>>> > >>>> It could, but I believe it would make sense to do both in one patch, > >>>> otherwise there will be a console serial port device mismatch between > >>>> the legacy and multiplatform cases. > >>> > >>> I'm a little confused. > >> > Does this patch introduce such a miss-match? > >> > >> Hi Laurent, > >> > >> I'd like to move this forwards somehow. > > > > This patch switches the Lager board to use SCIFA[01] instead of SCIF[01], > > while keeping the Linux devices named /dev/ttySC[67]. With legacy boot, > > SCIFA[01] are named /dev/ttySC[01]. There would thus be a mismatch in that > > sense, even if this change doesn't prevent using the same Linux serial > > devices on both legacy and DT boot. > > So if I understand if correctly, booting with the current > "console=ttySC6,115200" > in /chosen/bootargs will give a working console for both legacy and > multi-platform, > but the underlying serial hardware block for the console differs (legacy > uses SCIF0, multi-platform uses SCIFA0)? As far as I understand that's correct. -- Regards, Laurent Pinchart