From patchwork Wed Nov 23 11:21:03 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tomasz Nowicki X-Patchwork-Id: 698167 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3tP0Kg3tZcz9t2F for ; Wed, 23 Nov 2016 22:21:59 +1100 (AEDT) Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=semihalf-com.20150623.gappssmtp.com header.i=@semihalf-com.20150623.gappssmtp.com header.b="yW5BrWT7"; dkim-atps=neutral Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934870AbcKWLVr (ORCPT ); Wed, 23 Nov 2016 06:21:47 -0500 Received: from mail-lf0-f44.google.com ([209.85.215.44]:36581 "EHLO mail-lf0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935640AbcKWLVH (ORCPT ); Wed, 23 Nov 2016 06:21:07 -0500 Received: by mail-lf0-f44.google.com with SMTP id t196so1144447lff.3 for ; Wed, 23 Nov 2016 03:21:06 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=semihalf-com.20150623.gappssmtp.com; s=20150623; h=subject:to:references:cc:from:message-id:date:user-agent :mime-version:in-reply-to:content-transfer-encoding; bh=atv/bUuNWuTgMMGJ5/uIAybUc4aTCP9y4kQOq6W/w4M=; b=yW5BrWT7eT2be8WFp584wI9x4xtTEwlP4D8+xg5X6WUQ6Zag+riqNIQ8BHXWOAnlo+ f0VoZgmVl25cMBCZ9g1objW/afxS3fPVB9sZXZSbbECNe+aKvgT3tk142AxMkLG4NyMq H1GLPk6Bd3Ltv2GNhVUsaSX5dnYebCGLRc4m9XNv4bdId4mTuRXeM1thoMbBMQxfC+kX eQIQE0n+Uas4nnFWAT0PAAgJcAUa5h1SMqFzGEGDcCELqED/A/MnJAqbZCeb3exsi1UO 2b5IZC7UxB3CLwk7NBvZ92NUzEeG83IMCDXFh/yewQ+U7apLkCVAAuP/s/B1ieCoUlSH HwqQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:subject:to:references:cc:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding; bh=atv/bUuNWuTgMMGJ5/uIAybUc4aTCP9y4kQOq6W/w4M=; b=aG2cupjFJsjQmrqgljoYq1b+EfBsQClZyd4KQWfUO35n6q2bEWnH1IkygG6aWeQRa9 /7/lQOm6oTin8s08Nu+S0z5jyJmzcw0SBrwlahONrIVFRRu9cr4XJ1Is05Qufnh04cZP wSwcsSOvL9iV0QWevsXQkMKmHjZW1vdBxq7O0XOQapCgNnuyDrrBdgS0j+CF6YzESRRF 60SeNB1ljwSHWo0RQTLr03GEBB31ESXosf1gWJmFHpscyWFhEJQj6RiQpMSH3kmP5Dwi zbPAXpYdNUp/USQuw/SzvHMeTJa2eYU9RaTHHPhCtBZWOgwlcFQGEEO73O5p3zT2wY5f JYxA== X-Gm-Message-State: AKaTC00kgtZbJIPX7XFohZrbpB2B8E3FHgbH20V9TsiSZXkpYul5ALEzkr0qGbUAAfqcQg== X-Received: by 10.46.9.5 with SMTP id 5mr886413ljj.23.1479900065265; Wed, 23 Nov 2016 03:21:05 -0800 (PST) Received: from [10.0.0.85] (31-172-191-173.noc.fibertech.net.pl. [31.172.191.173]) by smtp.googlemail.com with ESMTPSA id l34sm7115300lfi.4.2016.11.23.03.21.03 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 23 Nov 2016 03:21:04 -0800 (PST) Subject: Re: [PATCH V9 11/11] ARM64/PCI: Support for ACPI based PCI host controller To: Bjorn Helgaas References: <1465588519-11334-1-git-send-email-tn@semihalf.com> <1465588519-11334-12-git-send-email-tn@semihalf.com> <20161122231321.GA20246@bhelgaas-glaptop.roam.corp.google.com> Cc: arnd@arndb.de, will.deacon@arm.com, catalin.marinas@arm.com, rafael@kernel.org, hanjun.guo@linaro.org, Lorenzo.Pieralisi@arm.com, okaya@codeaurora.org, jchandra@broadcom.com, robert.richter@caviumnetworks.com, mw@semihalf.com, Liviu.Dudau@arm.com, ddaney@caviumnetworks.com, wangyijing@huawei.com, Suravee.Suthikulpanit@amd.com, msalter@redhat.com, linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, linaro-acpi@lists.linaro.org, jcm@redhat.com, andrea.gallo@linaro.org, dhdang@apm.com, jeremy.linton@arm.com, liudongdong3@huawei.com, cov@codeaurora.org From: Tomasz Nowicki Message-ID: Date: Wed, 23 Nov 2016 12:21:03 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Firefox/45.0 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: <20161122231321.GA20246@bhelgaas-glaptop.roam.corp.google.com> Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Hi Bjorn, On 23.11.2016 00:13, Bjorn Helgaas wrote: > Hi Tomasz, > > On Fri, Jun 10, 2016 at 09:55:19PM +0200, Tomasz Nowicki wrote: >> Implement pci_acpi_scan_root and other arch-specific call so that ARM64 >> can start using ACPI to setup and enumerate PCI buses. >> >> Prior to buses enumeration the pci_acpi_scan_root() implementation looks >> for configuration space start address (obtained through ACPI _CBA method or >> MCFG interface). If succeed, it uses ECAM library to create new mapping. >> Then it attaches generic ECAM ops (pci_generic_ecam_ops) which are used >> for accessing configuration space later on. >> ... > >> +static struct acpi_pci_root_ops acpi_pci_root_ops = { >> + .release_info = pci_acpi_generic_release_info, >> +}; >> + >> +/* Interface called from ACPI code to setup PCI host controller */ >> struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root) >> { >> - /* TODO: Should be revisited when implementing PCI on ACPI */ >> - return NULL; >> + int node = acpi_get_node(root->device->handle); >> + struct acpi_pci_generic_root_info *ri; >> + struct pci_bus *bus, *child; >> + >> + ri = kzalloc_node(sizeof(*ri), GFP_KERNEL, node); >> + if (!ri) >> + return NULL; >> + >> + ri->cfg = pci_acpi_setup_ecam_mapping(root); >> + if (!ri->cfg) { >> + kfree(ri); >> + return NULL; >> + } >> + >> + acpi_pci_root_ops.pci_ops = &ri->cfg->ops->pci_ops; > > This has already been merged, but this isn't right, is it? We're > writing a host controller-specific pointer into the single system-wide > acpi_pci_root_ops, then passing it on to acpi_pci_root_create(). > > Today, I think ri->cfg->ops->pci_ops is always &pci_generic_ecam_ops, > from this path: > > ri->cfg = pci_acpi_setup_ecam_mapping > cfg = pci_ecam_create(..., &pci_generic_ecam_ops) > cfg = kzalloc(...) > cfg->ops = ops # &pci_generic_ecam_ops > > But we're about to merge the ECAM quirks series, which will mean it > may not be &pci_generic_ecam_ops. Even apart from the ECAM quirks, we > should avoid this pattern of putting device-specific info in a single > shared structure because it's too difficult to verify that it's > correct. > Well spotted. I agree, we need to fix this. How about this: Of course, this should be the part of ECAM quirks core patches. The other option we have is to remove "struct pci_ops *pci_ops;" from acpi_pci_root_ops structure and pass struct pci_ops as an extra argument to acpi_pci_root_create(). What do you think? Thanks, Tomasz --- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/arch/arm64/kernel/pci.c b/arch/arm64/kernel/pci.c index fb439c7..31c0e1c 100644 --- a/arch/arm64/kernel/pci.c +++ b/arch/arm64/kernel/pci.c @@ -152,33 +152,35 @@ static void pci_acpi_generic_release_info(struct acpi_pci_root_info *ci) ri = container_of(ci, struct acpi_pci_generic_root_info, common); pci_ecam_free(ri->cfg); + kfree(ci->ops); kfree(ri); } -static struct acpi_pci_root_ops acpi_pci_root_ops = { - .release_info = pci_acpi_generic_release_info, -}; - /* Interface called from ACPI code to setup PCI host controller */ struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root) { int node = acpi_get_node(root->device->handle); struct acpi_pci_generic_root_info *ri; struct pci_bus *bus, *child; + struct acpi_pci_root_ops *root_ops; ri = kzalloc_node(sizeof(*ri), GFP_KERNEL, node); if (!ri) return NULL; + root_ops = kzalloc_node(sizeof(*root_ops), GFP_KERNEL, node); + if (!root_ops) + return NULL; + ri->cfg = pci_acpi_setup_ecam_mapping(root); if (!ri->cfg) { kfree(ri); + kfree(root_ops); return NULL; } - acpi_pci_root_ops.pci_ops = &ri->cfg->ops->pci_ops; - bus = acpi_pci_root_create(root, &acpi_pci_root_ops, &ri->common, - ri->cfg); + root_ops->release_info = pci_acpi_generic_release_info; + root_ops->pci_ops = &ri->cfg->ops->pci_ops; + bus = acpi_pci_root_create(root, root_ops, &ri->common, ri->cfg); if (!bus) return NULL;