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=-8.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FAKE_REPLY_C,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 36724C4CECE for ; Thu, 12 Mar 2020 20:59:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 043C72074A for ; Thu, 12 Mar 2020 20:59:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584046742; bh=sZrxWzYm4Q2gQ/nKayUGqNHfr3nP8m8qZiAHKqaks08=; h=Date:From:To:Cc:Subject:In-Reply-To:List-ID:From; b=SWs/r9j+UfedOifhR8GdIy49cwB4ZNTUbJQLB3NBxLedK7+y2J7+A4QwHY+KMH7qM AZZAwRmTZUji15k3Q/iN8npGgNlAKHoZE6mFPLAD70V4+coPSBaaxOXpTs2ad89dz/ bMSTGJguOBdSsYbh1aEqO99l0vZ1ilbo5k/G+j8w= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726882AbgCLU7B (ORCPT ); Thu, 12 Mar 2020 16:59:01 -0400 Received: from mail.kernel.org ([198.145.29.99]:45528 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726246AbgCLU7A (ORCPT ); Thu, 12 Mar 2020 16:59:00 -0400 Received: from localhost (mobile-166-175-186-165.mycingular.net [166.175.186.165]) (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 CA66B206B7; Thu, 12 Mar 2020 20:58:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584046740; bh=sZrxWzYm4Q2gQ/nKayUGqNHfr3nP8m8qZiAHKqaks08=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=YoAaCQPJTwGmp7XWP86L78EAbP87WHaly0Mp6Ed8cwzHqWkTNzAekl0Vckbc5pcmt sHCTW0fPtyDVPWOuPF8zuumu2s9LhFTzzRroslWpC97D1efkVIlDqL6XyysJdOWTM/ cfylvimv3zTN/vGEqEvIIqwZ9L3tXOyXL77JU+ks= Date: Thu, 12 Mar 2020 15:58:58 -0500 From: Bjorn Helgaas To: Jean-Philippe Brucker Cc: will@kernel.org, robh+dt@kernel.org, joro@8bytes.org, baolu.lu@linux.intel.com, sudeep.holla@arm.com, linux-doc@vger.kernel.org, linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, linux-acpi@vger.kernel.org, iommu@lists.linux-foundation.org, lorenzo.pieralisi@arm.com, corbet@lwn.net, mark.rutland@arm.com, liviu.dudau@arm.com, guohanjun@huawei.com, rjw@rjwysocki.net, lenb@kernel.org, robin.murphy@arm.com, dwmw2@infradead.org, amurray@thegoodpenguin.co.uk, frowand.list@gmail.com Subject: Re: [PATCH v2 04/11] ACPI/IORT: Check ATS capability in root complex node Message-ID: <20200312205858.GA178807@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200311124506.208376-5-jean-philippe@linaro.org> User-Agent: Mutt/1.12.2 (2019-09-21) Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Wed, Mar 11, 2020 at 01:44:59PM +0100, Jean-Philippe Brucker wrote: > When initializing a PCI root bridge, copy its "ATS supported" attribute > into the root bridge. > > Acked-by: Hanjun Guo > Signed-off-by: Jean-Philippe Brucker > --- > drivers/acpi/arm64/iort.c | 27 +++++++++++++++++++++++++++ > drivers/acpi/pci_root.c | 3 +++ > include/linux/acpi_iort.h | 8 ++++++++ > 3 files changed, 38 insertions(+) > > diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c > index ed3d2d1a7ae9..d99d7f5b51e1 100644 > --- a/drivers/acpi/arm64/iort.c > +++ b/drivers/acpi/arm64/iort.c > @@ -1633,6 +1633,33 @@ static void __init iort_enable_acs(struct acpi_iort_node *iort_node) > } > } > } > + > +static acpi_status iort_match_host_bridge_callback(struct acpi_iort_node *node, > + void *context) > +{ > + struct acpi_iort_root_complex *pci_rc; > + struct pci_host_bridge *host_bridge = context; > + > + pci_rc = (struct acpi_iort_root_complex *)node->node_data; > + > + return pci_domain_nr(host_bridge->bus) == pci_rc->pci_segment_number ? > + AE_OK : AE_NOT_FOUND; > +} > + > +void iort_pci_host_bridge_setup(struct pci_host_bridge *host_bridge) > +{ > + struct acpi_iort_node *node; > + struct acpi_iort_root_complex *pci_rc; > + > + node = iort_scan_node(ACPI_IORT_NODE_PCI_ROOT_COMPLEX, > + iort_match_host_bridge_callback, host_bridge); > + if (!node) > + return; > + > + pci_rc = (struct acpi_iort_root_complex *)node->node_data; > + host_bridge->ats_supported = !!(pci_rc->ats_attribute & > + ACPI_IORT_ATS_SUPPORTED); > +} > #else > static inline void iort_enable_acs(struct acpi_iort_node *iort_node) { } > #endif > diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c > index d1e666ef3fcc..eb2fb8f17c0b 100644 > --- a/drivers/acpi/pci_root.c > +++ b/drivers/acpi/pci_root.c > @@ -6,6 +6,7 @@ > * Copyright (C) 2001, 2002 Paul Diefenbaugh > */ > > +#include > #include > #include > #include > @@ -917,6 +918,8 @@ struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root, > if (!(root->osc_control_set & OSC_PCI_EXPRESS_LTR_CONTROL)) > host_bridge->native_ltr = 0; > > + iort_pci_host_bridge_setup(host_bridge); Similar comment as on the OF side. You mentioned at [1] that "it's important that we only enable ATS if the host bridge supports it". That should be captured in a commit log and comment somewhere here. That suggests to me that we should not set bridge->ats_supported = 1; by default in pci_init_host_bridge(), but rather leave it zero as it is by default, and then do things like: if (iort_pci_host_bridge_ats_supported(bridge)) bridge->ats_supported = 1; if (of_pci_host_bridge_ats_supported(bridge)) bridge->ats_supported = 1; I don't know what you do about IVRS and DMAR, which don't appear in this series except in the comment. [1] https://lore.kernel.org/r/20200213165049.508908-1-jean-philippe@linaro.org > /* > * Evaluate the "PCI Boot Configuration" _DSM Function. If it > * exists and returns 0, we must preserve any PCI resource > diff --git a/include/linux/acpi_iort.h b/include/linux/acpi_iort.h > index 8e7e2ec37f1b..7b06871cc3aa 100644 > --- a/include/linux/acpi_iort.h > +++ b/include/linux/acpi_iort.h > @@ -10,6 +10,7 @@ > #include > #include > #include > +#include > > #define IORT_IRQ_MASK(irq) (irq & 0xffffffffULL) > #define IORT_IRQ_TRIGGER_MASK(irq) ((irq >> 32) & 0xffffffffULL) > @@ -55,4 +56,11 @@ int iort_iommu_msi_get_resv_regions(struct device *dev, struct list_head *head) > { return 0; } > #endif > > +#if defined(CONFIG_ACPI_IORT) && defined(CONFIG_PCI) > +void iort_pci_host_bridge_setup(struct pci_host_bridge *host_bridge); > +#else > +static inline > +void iort_pci_host_bridge_setup(struct pci_host_bridge *host_bridge) { } > +#endif > + > #endif /* __ACPI_IORT_H__ */ > -- > 2.25.1 >