Re: [PATCH v2] tty: serial: msm: Don't reconfigure same baud rate

[Srinivas Kandagatla]

On 21/06/16 10:43, Nicolas Dechesne wrote:
> On Fri, Jun 17, 2016 at 1:02 PM, Nicolas Dechesne
> <nicolas.dechesne@xxxxxxxxxx> wrote:
> > <bjorn.andersson@xxxxxxxxxx> wrote:
> > > msm_set_termios() is called whenever the tty is opened. Setting the baud
> > > rate requires a full reset of the msm serial block, even when the rate
> > > is unchanged. In the case when the same uart is used as console this
> > > reset will discard any console output data still being clocked out of
> > > the TX fifo.
> > >
> > > By skipping the rate-change in the case where the baud rate is unchanged
> > > since last request we can avoid the reset and the discarding of the
> > > data.
> > >
> > > Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
> >
> >
> > Tested-by: Nicolas Dechesne <nicolas.dechesne@xxxxxxxxxx>
> >
> > I no longer see this type of corruption on serial console
> >
> > [    6.325118] ALSA device ï[    6.333338] Freeing unused kernel
> > memory: 572K (ffffffc000c10000 - ffffffc000c9f000)
> > [   13.800269]  remoteproc2: remote processor a20400ï[  OK  ] Started
> > Start the WCN core.
> > [ ï         Starting Update UTMP about System Runlevel Changes...
>
>
> oops. today i tried on APQ8064 boards , both IFC6410Plus and SD
> 600eval, and I can no longer 'type' into the serial console, I can get
> debug messages though. Reverting this change 'fixes' the problem.

Am also hitting the same issue as Nico on IFC6410 with this patch.


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