From mboxrd@z Thu Jan 1 00:00:00 1970 From: NeilBrown Subject: Re: patch "tty: serial: OMAP: ensure FIFO levels are set correctly in non-DMA" added to tty tree Date: Sat, 4 Feb 2012 14:43:53 +1100 Message-ID: <20120204144353.0803fe23@notabene.brown> References: <13274430881471@kroah.org> <20120126042155.GA3185@suse.de> <20120126191604.GA15516@suse.de> <20120203150708.386951d2@notabene.brown> <20120203205401.5ddf241d@notabene.brown> <20120204085940.2de44594@notabene.brown> <20120204110131.7378b8fe@notabene.brown> <20120204140923.063706c8@notabene.brown> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=PGP-SHA1; boundary="Sig_/z.q4=aAMemSNsuwP9Okc2EE"; protocol="application/pgp-signature" Return-path: In-Reply-To: Sender: linux-omap-owner@vger.kernel.org To: Paul Walmsley Cc: greg@kroah.com, khilman@ti.com, govindraj.raja@ti.com, tomi.valkeinen@ti.com, linux-serial@vger.kernel.org, linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org List-Id: linux-serial@vger.kernel.org --Sig_/z.q4=aAMemSNsuwP9Okc2EE Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Fri, 3 Feb 2012 20:16:08 -0700 (MST) Paul Walmsley wrot= e: > On Sat, 4 Feb 2012, NeilBrown wrote: >=20 > > On Fri, 3 Feb 2012 19:06:19 -0700 (MST) Paul Walmsley = wrote: > > >=20 > > > Here's a patch that helps. It seems to work down to an=20 > > > autosuspend_delay_ms of 1 ms. Without it, the best I can get is 8 ms. > > >=20 > > > Of course, ideally it should work fine at autosuspend_delay_ms =3D 0,= so=20 > > > likely there's some other infelicity that we're currently missing. > > >=20 > > > Neil, care to give this a test and confirm it on your setup? > >=20 > > Yes, that seems to make the output corruption go away. >=20 > Cool, thanks for the test :-) >=20 > > Even with small autosuspend_delay_ms down to 0 it doesn't corrupt outpu= t, > > but as the first input byte is corrupted, I cannot really type with tho= se > > setting (so I ssh to gain control again). >=20 > Could you try pasting in a buffer from another window? If I paste in the= =20 > buffer at the bottom of this message a few times, I see some output=20 > corruption.=20 I have to set autosuspend_delay_ms for omap_uart.3 as well before the behaviour is significant. But then I see no output corruption. Lots of input corruption of course but the output looks fine. NeilBrown >=20 >=20 > - Paul >=20 >=20 > =20 > ; > ; > ; > ; > cat /sys/devices/platform/omap/omap_uart.2/power/autosuspend_delay_ms > echo 0 > /sys/devices/platform/omap/omap_uart.2/power/autosuspend_delay_ms > cat /proc/interrupts > ; >=20 > -- > To unsubscribe from this list: send the line "unsubscribe linux-omap" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html --Sig_/z.q4=aAMemSNsuwP9Okc2EE Content-Type: application/pgp-signature; name=signature.asc Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.18 (GNU/Linux) iQIVAwUBTyypeTnsnt1WYoG5AQKznRAAwJJNdnEAu42CEowscBKi5aYANuO8AED1 X3C+5nXQgr01lg/uTGpX95BvlVg0U8HXa/UT8pAf+08gPxpZvyVJSZjFkgfOE2yN rjMq4DLTxcFwTJ1TNiVYLB/+CVTw8TiVvrZFSVe3YESFFCMP8uvtvUVG9AYWlCrc NVbugEf3P8rGNyO5YjEOjaKsD3JCIT0mzkbBRd4d9K1/Kjen/JAJQ24+OZOuzxJR BA9R+EiS9ZU9CFv0IC0SNHvfqPKQhNIFEfsOwFb3L2YJzOl2XVwmaRIeKWjedP5J WbS4HvJWdPtoA4Vkq07C9XFxaKRQ0+V7dL5dSbUuKp2Fo1O6yJsUlNcnEpwoGTAP /KeOkCu6z5i4lrSf7rzR1Td7jOzBm8ewt/pQALGA7hFqvYyiot4CQCrrkmYPL687 b05+254jhmcFJ9PLgwjbIzbaUiUjUX86zwuny6CF0MlwkaOExDKRg/viJxsCKLPp uQzDK0PGD9am3B9m5/dMzh7TH6we9+qHHFBpqiVGfT2BPJIA4xvIZAdTwpr85ZGM CzJIeOU5Sr7vImCh/b3iaf/ejmthRfLddP7mvDGoBOiHSIlI7Tc8eWvMYN1qx7eW C4dLPdFsX6x4kKF680ysMvlXmtwnpdY4TTxGe9D4QReyWIXRNNrdj7Wo8uCjWbwe NZnJpd0IgJs= =dwyH -----END PGP SIGNATURE----- --Sig_/z.q4=aAMemSNsuwP9Okc2EE--