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 A2359C4332F for ; Thu, 10 Nov 2022 21:07:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232119AbiKJVHs (ORCPT ); Thu, 10 Nov 2022 16:07:48 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59496 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232103AbiKJVHh (ORCPT ); Thu, 10 Nov 2022 16:07:37 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6872258BD6; Thu, 10 Nov 2022 13:07:36 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id E1134B8238E; Thu, 10 Nov 2022 21:07:34 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 61E41C433C1; Thu, 10 Nov 2022 21:07:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1668114453; bh=9J/8mtPefAQqogh4jFlbGu4+fqQ9vN2bfV5hD1uWbrI=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=ZWu+EBIa70QL4S8G0ObyISCrLNZ0uU2/EmFiyH5ZJv4RsNowDJ7nogF6AphwUiSPy madpFJ0j6Pl83dzdkBcyB6rPKS1MfeUytJaSrA+0ba8o0On0bVyDrq5HK5UB9r6vrC c3NGAGSqgOpw59O+lsYebPWLj0Dvluoe1wXxzjOk0O4SJ6NTld+GIztG62bvXQ5sCz qtIM4Vw9KVpUkcFe5vdLGRwPSU2wpIBWII7ZxZELKelwdbpUa+oe63tY54ORtOlUjP F4Mz0vK4t9DegeViF+JS6PHMFSaSN1kz1rIuMAlzPJiE5aIf9T4VSxh9SGuEPeIH2d Q91vXEvBMEjVA== Date: Thu, 10 Nov 2022 15:07:31 -0600 From: Bjorn Helgaas To: Liu Peibao Cc: Bjorn Helgaas , Rob Herring , Krzysztof Kozlowski , Lorenzo Pieralisi , Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= , Jiaxun Yang , Christophe JAILLET , Huacai Chen , Jianmin Lv , Yinbo Zhu , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH V4] PCI: loongson: Skip scanning unavailable child devices Message-ID: <20221110210731.GA672063@bhelgaas> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20221108064240.8030-1-liupeibao@loongson.cn> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Nov 08, 2022 at 02:42:40PM +0800, Liu Peibao wrote: > The PCI Controller of 2k1000 could not mask devices by setting vender ID or > device ID in configuration space header as invalid values. When there are > pins shareable between the platform device and PCI device, if the platform > device is preferred, we should not scan this PCI device. In the above > scene, add `status = "disabled"` property in DT node of this PCI device. > > Signed-off-by: Liu Peibao > --- > V3 -> V4: 1. get rid of the masklist and search the status property > directly. > 2. check the status property only when accessing the vendor ID. > V2 -> V3: 1. use list_for_each_entry() for more clearly. > 2. fix wrong use of sizeof(). > V1 -> V2: use existing property "status" instead of adding new property. > > drivers/pci/controller/pci-loongson.c | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/drivers/pci/controller/pci-loongson.c b/drivers/pci/controller/pci-loongson.c > index 05c50408f13b..efca0b3b5a29 100644 > --- a/drivers/pci/controller/pci-loongson.c > +++ b/drivers/pci/controller/pci-loongson.c > @@ -194,6 +194,17 @@ static void __iomem *pci_loongson_map_bus(struct pci_bus *bus, > return NULL; > } > > +#ifdef CONFIG_OF > + /* Don't access disabled devices. */ > + if (pci_is_root_bus(bus) && where == PCI_VENDOR_ID) { > + struct device_node *dn; > + > + dn = of_pci_find_child_device(bus->dev.of_node, devfn); > + if (dn && !of_device_is_available(dn)) > + return NULL; > + } > +#endif Looks nice and simple, thanks for trying this out. > /* CFG0 can only access standard space */ > if (where < PCI_CFG_SPACE_SIZE && priv->cfg0_base) > return cfg0_map(priv, bus, devfn, where); > -- > 2.20.1 >