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 1A9AFC43334 for ; Thu, 21 Jul 2022 08:50:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232079AbiGUIuS (ORCPT ); Thu, 21 Jul 2022 04:50:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52100 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229539AbiGUIuP (ORCPT ); Thu, 21 Jul 2022 04:50:15 -0400 Received: from pandora.armlinux.org.uk (pandora.armlinux.org.uk [IPv6:2001:4d48:ad52:32c8:5054:ff:fe00:142]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 12B26EB4 for ; Thu, 21 Jul 2022 01:50:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=Rk/aX50MwzZ83ghgQLTLTJVjsWpYCc/vPUglmdR9NS0=; b=m6Lpl+KIQXkLBLKTqSg58v8vgY MSMeXu0/hxR0tuu7sADwKP77680vVT08h5BzBXJuTHnxhY3uQaOKnm0M0eoszN0REPG1RLI6z97LZ sRBGXCMWHc2GZwPOTTHo5hNA68RGVlhK3bNC8+2G+l6BaP5N7GfqjZF32OfAQ6mIbJ5QtkGh8hoVk CMylsKu/m06CAYO/bFqSV1jMysAydhs91wRngY/qYNPxDR1CHxnMnCInbLQk5yEQh2hmadXoO/xJ/ vlRqGmJD0AonanT5MWuEOpultqCRMeznG0N94jToD3Yw6zhYdnn1Fs3ueKfpiKOcdDlFxTcOT7gaO +SsB1kIQ==; Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:33476) by pandora.armlinux.org.uk with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1oERsX-0004zm-Nc; Thu, 21 Jul 2022 09:49:53 +0100 Received: from linux by shell.armlinux.org.uk with local (Exim 4.94.2) (envelope-from ) id 1oERsR-0004ix-Vy; Thu, 21 Jul 2022 09:49:48 +0100 Date: Thu, 21 Jul 2022 09:49:47 +0100 From: "Russell King (Oracle)" To: Sudeep Holla , Saravana Kannan Cc: Philipp Zabel , Rob Herring , Ulf Hansson , Linus Walleij , Nicolas Saenz Julienne , Geert Uytterhoeven , Marek Szyprowski , Kefeng Wang , Greg Kroah-Hartman , kernel-team@android.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH v5] amba: Remove deferred device addition Message-ID: References: <20220719182010.637337-1-saravanak@google.com> <20220720131221.azqfidkry3cwiarw@bogus> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220720131221.azqfidkry3cwiarw@bogus> Sender: Russell King (Oracle) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jul 20, 2022 at 02:12:21PM +0100, Sudeep Holla wrote: > On Tue, Jul 19, 2022 at 11:20:10AM -0700, Saravana Kannan wrote: > > The uevents generated for an amba device need PID and CID information > > that's available only when the amba device is powered on, clocked and > > out of reset. So, if those resources aren't available, the information > > can't be read to generate the uevents. To workaround this requirement, > > if the resources weren't available, the device addition was deferred and > > retried periodically. > > > > However, this deferred addition retry isn't based on resources becoming > > available. Instead, it's retried every 5 seconds and causes arbitrary > > probe delays for amba devices and their consumers. > > > > Also, maintaining a separate deferred-probe like mechanism is > > maintenance headache. > > > > With this commit, instead of deferring the device addition, we simply > > defer the generation of uevents for the device and probing of the device > > (because drivers needs PID and CID to match) until the PID and CID > > information can be read. This allows us to delete all the amba specific > > deferring code and also avoid the arbitrary probing delays. > > > > Cc: Rob Herring > > Cc: Ulf Hansson > > Cc: Saravana Kannan > > Cc: Linus Walleij > > Cc: Sudeep Holla > > Tested-by: Sudeep Holla > > on Juno with linux-next(which had the reported issue [1]) + this patch(which > fixes the issue) Ok, but this patch needs to end up in the patch system for me to apply it. Can someone please add "KernelVersion: 5.19-rc7" or whatever version the patch was generated against (just the tagged version is sufficient) somewhere in the email, and send it to patches@armlinu.org.uk. Thanks. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!