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=-11.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 8914FC433E0 for ; Mon, 3 Aug 2020 14:46:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6342C2076E for ; Mon, 3 Aug 2020 14:46:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1596465997; bh=EedRPINOKfpkKJFcMma8Y9eMI4MC2bcF2mDpZ3GPHJM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=R6bqWYosM49Af8EHWoFZbwXJNLl9UBqqhEa1cjdPjssXAhHdmE6X/jNuZ8eN3ZeR6 skFYSariVow8Im7GPwZLwKkMkljqlOjqjqMDJ59rkTLP8uZCBVw4OEAXEqUoEt06k4 ujDcyCDD+dmUhw5XGAU85ti79RVlaxRcpaOwKTIQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726358AbgHCOqh (ORCPT ); Mon, 3 Aug 2020 10:46:37 -0400 Received: from mail.kernel.org ([198.145.29.99]:40898 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726189AbgHCOqh (ORCPT ); Mon, 3 Aug 2020 10:46:37 -0400 Received: from pali.im (pali.im [31.31.79.79]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9C64C206D7; Mon, 3 Aug 2020 14:46:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1596465995; bh=EedRPINOKfpkKJFcMma8Y9eMI4MC2bcF2mDpZ3GPHJM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=IwaBT7lWkehhcjmXNFPkyfd+oAlG8VzGlsuplyxppCBzmutiVjnidPYNCq0FwwcGA 0+H7xupjlZJbFD/S2T3/qPDPRMcDRvL8Cu9k4Rzhg1LmOtP98HsWXuqB/1sYv6GNGW xnIRLYEwT+XHNZs83VMSK8uzKa+ujtwxt3IwTer8= Received: by pali.im (Postfix) id C0A3A121D; Mon, 3 Aug 2020 16:46:34 +0200 (CEST) Date: Mon, 3 Aug 2020 16:46:34 +0200 From: Pali =?utf-8?B?Um9ow6Fy?= To: Rob Herring Cc: Marek =?utf-8?B?QmVow7pu?= , linux-pci@vger.kernel.org, Tomasz Maciej Nowak , Gregory Clement , Bjorn Helgaas , Lorenzo Pieralisi , linux-kernel@vger.kernel.org, Andrew Lunn , Xogium Subject: Re: [PATCH 4/5] PCI: aardvark: Implement driver 'remove' function and allow to build it as module Message-ID: <20200803144634.nr5cjddyvdnv3lxo@pali> References: <20200715142557.17115-1-marek.behun@nic.cz> <20200715142557.17115-5-marek.behun@nic.cz> <20200729184809.GA569408@bogus> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20200729184809.GA569408@bogus> User-Agent: NeoMutt/20180716 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Wednesday 29 July 2020 12:48:09 Rob Herring wrote: > On Wed, Jul 15, 2020 at 04:25:56PM +0200, Marek Behún wrote: > > From: Pali Rohár > > > > Providing driver's 'remove' function allows kernel to bind and unbind devices > > from aardvark driver. It also allows to build aardvark driver as a module. > > > > Compiling aardvark as a module simplifies development and debugging of > > this driver as it can be reloaded at runtime without the need to reboot > > to new kernel. > > > > Signed-off-by: Pali Rohár > > Reviewed-by: Marek Behún > > --- > > drivers/pci/controller/Kconfig | 2 +- > > drivers/pci/controller/pci-aardvark.c | 25 ++++++++++++++++++++++--- > > 2 files changed, 23 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/pci/controller/Kconfig b/drivers/pci/controller/Kconfig > > index adddf21fa381..f9da5ff2c517 100644 > > --- a/drivers/pci/controller/Kconfig > > +++ b/drivers/pci/controller/Kconfig > > @@ -12,7 +12,7 @@ config PCI_MVEBU > > select PCI_BRIDGE_EMUL > > > > config PCI_AARDVARK > > - bool "Aardvark PCIe controller" > > + tristate "Aardvark PCIe controller" > > depends on (ARCH_MVEBU && ARM64) || COMPILE_TEST > > depends on OF > > depends on PCI_MSI_IRQ_DOMAIN > > diff --git a/drivers/pci/controller/pci-aardvark.c b/drivers/pci/controller/pci-aardvark.c > > index d5f58684d962..0a5aa6d77f5d 100644 > > --- a/drivers/pci/controller/pci-aardvark.c > > +++ b/drivers/pci/controller/pci-aardvark.c > > @@ -14,6 +14,7 @@ > > #include > > #include > > #include > > +#include > > #include > > #include > > #include > > @@ -1114,6 +1115,7 @@ static int advk_pcie_probe(struct platform_device *pdev) > > > > pcie = pci_host_bridge_priv(bridge); > > pcie->pdev = pdev; > > + platform_set_drvdata(pdev, pcie); > > > > res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > > pcie->base = devm_ioremap_resource(dev, res); > > @@ -1204,18 +1206,35 @@ static int advk_pcie_probe(struct platform_device *pdev) > > return 0; > > } > > > > +static int advk_pcie_remove(struct platform_device *pdev) > > +{ > > + struct advk_pcie *pcie = platform_get_drvdata(pdev); > > + struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie); > > + > > + pci_stop_root_bus(bridge->bus); > > + pci_remove_root_bus(bridge->bus); > > Based on pci_host_common_remove() implementation, doesn't this need a > lock around it (pci_lock_rescan_remove)? Well, I'm not sure. I looked into other pci drivers and none of following drivers pci-tegra.c, pcie-altera.c, pcie-brcmstb.c, pcie-iproc.c, pcie-mediatek.c, pcie-rockchip-host.c calls pci_lock_rescan_remove() and pci_unlock_rescan_remove(). Only pci-host-common.c and pci-hyperv.c protect pci_stop_root_bus() and pci_remove_root_bus() by locks. > We should probably have a common function (say pci_bridge_remove) to > implement this. You could use pci_host_common_remove(), but you'd have > to adjust drvdata. Ok, I agree that some common function could be useful as the same code (pci_stop_root_bus(); pci_remove_root_bus();) is called in more pci drivers. But first we need to know if locks are required or not. > > + > > + advk_pcie_remove_msi_irq_domain(pcie); > > + advk_pcie_remove_irq_domain(pcie); > > + > > + return 0; > > +} > > + > > static const struct of_device_id advk_pcie_of_match_table[] = { > > { .compatible = "marvell,armada-3700-pcie", }, > > {}, > > }; > > +MODULE_DEVICE_TABLE(of, advk_pcie_of_match_table); > > > > static struct platform_driver advk_pcie_driver = { > > .driver = { > > .name = "advk-pcie", > > .of_match_table = advk_pcie_of_match_table, > > - /* Driver unloading/unbinding currently not supported */ > > - .suppress_bind_attrs = true, > > }, > > .probe = advk_pcie_probe, > > + .remove = advk_pcie_remove, > > }; > > -builtin_platform_driver(advk_pcie_driver); > > +module_platform_driver(advk_pcie_driver); > > + > > +MODULE_DESCRIPTION("Aardvark PCIe controller"); > > +MODULE_LICENSE("GPL v2"); > > -- > > 2.26.2 > >