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 X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6BB4AC04EB9 for ; Mon, 3 Dec 2018 22:18:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 38EDB20851 for ; Mon, 3 Dec 2018 22:18:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 38EDB20851 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=bootlin.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-pci-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725893AbeLCWS6 convert rfc822-to-8bit (ORCPT ); Mon, 3 Dec 2018 17:18:58 -0500 Received: from mail.bootlin.com ([62.4.15.54]:34451 "EHLO mail.bootlin.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725873AbeLCWS6 (ORCPT ); Mon, 3 Dec 2018 17:18:58 -0500 Received: by mail.bootlin.com (Postfix, from userid 110) id C9D6620791; Mon, 3 Dec 2018 23:18:55 +0100 (CET) Received: from xps13 (unknown [91.224.148.103]) by mail.bootlin.com (Postfix) with ESMTPSA id BDCEC207AD; Mon, 3 Dec 2018 23:18:44 +0100 (CET) Date: Mon, 3 Dec 2018 23:18:44 +0100 From: Miquel Raynal To: "Rafael J. Wysocki" Cc: Lorenzo Pieralisi , sudeep.holla@arm.com, Gregory Clement , Jason Cooper , Andrew Lunn , Sebastian Hesselbarth , Thomas Petazzoni , Bjorn Helgaas , devicetree@vger.kernel.org, Rob Herring , Mark Rutland , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Antoine Tenart , Maxime Chevallier , Nadav Haklai Subject: Re: [PATCH 05/12] PCI: aardvark: add suspend to RAM support Message-ID: <20181203231844.0791bdee@xps13> In-Reply-To: <1999610.6DN9RK2Tt3@aspire.rjw.lan> References: <20181123141831.8214-1-miquel.raynal@bootlin.com> <20181203102708.GA6090@e107981-ln.cambridge.arm.com> <20181203163846.494904f9@xps13> <1999610.6DN9RK2Tt3@aspire.rjw.lan> Organization: Bootlin X-Mailer: Claws Mail 3.17.1 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Hi Rafael, Stephen, "Rafael J. Wysocki" wrote on Mon, 03 Dec 2018 23:00:20 +0100: > On Monday, December 3, 2018 4:38:46 PM CET Miquel Raynal wrote: > > Hi Lorenzo, > > > > Lorenzo Pieralisi wrote on Mon, 3 Dec 2018 > > 10:27:08 +0000: > > > > > [+Rafael, Sudeep] > > > > > > On Fri, Nov 23, 2018 at 03:18:24PM +0100, Miquel Raynal wrote: > > > > Add suspend and resume callbacks. The priority of these are > > > > "_noirq()", to workaround early access to the registers done by the > > > > PCI core through the ->read()/->write() callbacks at resume time. > > > > > > > > Signed-off-by: Miquel Raynal > > > > --- > > > > drivers/pci/controller/pci-aardvark.c | 52 +++++++++++++++++++++++++++ > > > > 1 file changed, 52 insertions(+) > > > > > > > > diff --git a/drivers/pci/controller/pci-aardvark.c b/drivers/pci/controller/pci-aardvark.c > > > > index 108b3f15c410..7ecf1ac4036b 100644 > > > > --- a/drivers/pci/controller/pci-aardvark.c > > > > +++ b/drivers/pci/controller/pci-aardvark.c > > > > @@ -1108,6 +1108,55 @@ static int advk_pcie_setup_clk(struct advk_pcie *pcie) > > > > return ret; > > > > } > > > > > > > > +static int __maybe_unused advk_pcie_suspend(struct device *dev) > > > > +{ > > > > + struct advk_pcie *pcie = dev_get_drvdata(dev); > > > > + > > > > + advk_pcie_disable_phy(pcie); > > > > + > > > > + clk_disable_unprepare(pcie->clk); > > > > > > I have noticed it is common practice, still, I would like to check whether > > > it is allowed to call functions that may sleep in a NOIRQ suspend/resume > > > callback ? > > > > You are right this is weird. I double checked and for instance, > > pcie-mediatek.c, pci-tegra.c and pci-imx6.c do the exact same thing. There are > > probably other cases where drivers call functions that may sleep from a NOIRQ > > context. I am interested to know if this is valid and if not, what is the > > alternative? > > > > Yes, it is valid. _noirq means that the high-level action handlers will not be > invoked for interrupts occurring during that period, but that doesn't apply to > timer interrupts. > > IOW, don't expect *your* IRQ handler to be invoked then (if this is not a timer > IRQ), but you can sleep. > > Thanks, > Rafael > Thank you both for the enlightenment. Thanks, Miquèl