From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1Zx8RC-0000Hd-UT for barebox@lists.infradead.org; Fri, 13 Nov 2015 07:06:23 +0000 Date: Fri, 13 Nov 2015 08:06:00 +0100 From: Sascha Hauer Message-ID: <20151113070600.GX8526@pengutronix.de> References: <1447195492.4553.95.camel@rtred1test09.kymeta.local> <20151111080300.GO8526@pengutronix.de> <1447270216.4553.116.camel@rtred1test09.kymeta.local> <1447275243.4553.119.camel@rtred1test09.kymeta.local> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1447275243.4553.119.camel@rtred1test09.kymeta.local> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: [PATCH v3] net: designware: Don't hang in reset with powered down phy To: Trent Piepho Cc: barebox On Wed, Nov 11, 2015 at 08:54:01PM +0000, Trent Piepho wrote: > The dw MAC requires that all clock domains to be running for it to > finish a MAC reset. This include the clock provided by the PHY. > > If the PHY is powered down, bit BMCR_PDOWN set, then it won't be > generating a clock. And so the MAC never comes out of reset. On > shutdown, Linux will put the PHY in powerdown mode, so it can easily > be the case that the PHY is powered down on boot. > > See Linux kernel commit 2d871aa07136fe6e576bde63072cf33e2c664e95. > > Currently the MAC reset is done before the phy is probed. We can't > power up the phy until it's probed, so the resets must be in the > opposite order. The MAC reset is in device init but the PHY probe is > in device open. Device init is done first, always, while open is done > later, and only if the device is used. > > Rather than move the phy probe to init, this moves the MAC reset to > open. It seems better to speed up boots that doesn't use ethernet by > skipping MAC reset than to slow them down by adding PHY probe. > > Signed-off-by: Trent Piepho > --- > > Ignore v2, I missed a bunch of compiler warnings that scrolled off the > screen and barebox doesn't seem to be using -Werror. Newer compilers tend to introduce more warnings, so using -Werror would mean that an older barebox will likely not build with recent compiler versions. I had this problem with other projects sometimes, so I don't think that using -Werror is a good idea. Anyway, applied, thanks Sascha -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox