From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0453BCCA47D for ; Wed, 22 Jun 2022 11:21:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1357615AbiFVLVP (ORCPT ); Wed, 22 Jun 2022 07:21:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56868 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1357595AbiFVLUy (ORCPT ); Wed, 22 Jun 2022 07:20:54 -0400 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 780973CFC0 for ; Wed, 22 Jun 2022 04:19:16 -0700 (PDT) Received: from ptx.hi.pengutronix.de ([2001:67c:670:100:1d::c0]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1o3yNj-0002pw-5i; Wed, 22 Jun 2022 13:18:47 +0200 Received: from sha by ptx.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1o3yNV-0004vY-2O; Wed, 22 Jun 2022 13:18:33 +0200 Date: Wed, 22 Jun 2022 13:18:33 +0200 From: Sascha Hauer To: Andy Shevchenko Cc: Linus Walleij , Andrew Lunn , Ulf Hansson , "Rafael J. Wysocki" , Eric Dumazet , Pavel Machek , Will Deacon , Saravana Kannan , Kevin Hilman , Joerg Roedel , Russell King , Jakub Kicinski , Paolo Abeni , Android Kernel Team , Len Brown , Linux PM , "open list:GPIO SUBSYSTEM" , Hideaki YOSHIFUJI , Greg Kroah-Hartman , David Ahern , Linux Kernel Mailing List , "list@263.net:IOMMU DRIVERS" , Sascha Hauer , netdev , "David S. Miller" , Heiner Kallweit Subject: Re: [PATCH v2 7/9] driver core: Set fw_devlink.strict=1 by default Message-ID: <20220622111833.GW1615@pengutronix.de> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Sent-From: Pengutronix Hildesheim X-URL: http://www.pengutronix.de/ X-Accept-Language: de,en X-Accept-Content-Type: text/plain User-Agent: Mutt/1.10.1 (2018-07-13) X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::c0 X-SA-Exim-Mail-From: sha@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 22, 2022 at 12:52:02PM +0200, Andy Shevchenko wrote: > On Wed, Jun 22, 2022 at 10:44 AM Linus Walleij wrote: > > On Wed, Jun 22, 2022 at 9:48 AM Sascha Hauer wrote: > > ... > > > > This patch has the effect that console UART devices which have "dmas" > > > properties specified in the device tree get deferred for 10 to 20 > > > seconds. This happens on i.MX and likely on other SoCs as well. On i.MX > > > the dma channel is only requested at UART startup time and not at probe > > > time. dma is not used for the console. Nevertheless with this driver probe > > > defers until the dma engine driver is available. > > > > > > It shouldn't go in as-is. > > > > This affects all machines with the PL011 UART and DMAs specified as > > well. > > > > It would be best if the console subsystem could be treated special and > > not require DMA devlink to be satisfied before probing. > > In 8250 we force disable DMA and PM on kernel consoles, because it's > so-o PITA and has a lot of corner cases we may never chase down. On i.MX this is done as well, but it doesn't help here. The driver is not even probed when the device node contains a "dmas" property. Sascha -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |