From patchwork Wed Sep 23 00:00:04 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Daney X-Patchwork-Id: 7246601 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 14C92BEEC1 for ; Wed, 23 Sep 2015 00:03:36 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 07C6A207A9 for ; Wed, 23 Sep 2015 00:03:35 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id EC00820797 for ; Wed, 23 Sep 2015 00:03:33 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZeXUd-0004uY-O5; Wed, 23 Sep 2015 00:01:03 +0000 Received: from mail-io0-x236.google.com ([2607:f8b0:4001:c06::236]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZeXUA-0004ae-K2 for linux-arm-kernel@lists.infradead.org; Wed, 23 Sep 2015 00:00:36 +0000 Received: by iofh134 with SMTP id h134so30258830iof.0 for ; Tue, 22 Sep 2015 17:00:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=AB5/iq1K1kyNPQvFMpUv9U6KcHXZ0nDG5IKfu0fwsN0=; b=eyQb/mZPWSS7fyBCnHIpBXb1ccuaEXDDm0iHRjCLhyp4WWu9FcPje1KFZ9K+P91kgw TatWs5mEvaegl2RR7d2qAfBhaEMVg6t/AXo+H1fDDWFrXMy9MCAWzpJHbyDXi6O9a6TK 8Jtp74eLvhBselo2QbV67tKGAafU/ByF6OjFsObvYudvHj2k2axKRgx+n3SRWnpw/apn 2ygVLUwb3BLeKP2w3Fi7HV7ePG7qm1FtaT0Ja53YmZ6NbzG5/4/yaWM7IUSsZrMCRh5y lkfHIwHDpuF1OICvmgjIte4+H2DST+5TIkraCLr0a7oMfKqg1Qtpk7UQ9X87AC6fM2xE oAAA== X-Received: by 10.107.6.74 with SMTP id 71mr35386536iog.16.1442966413865; Tue, 22 Sep 2015 17:00:13 -0700 (PDT) Received: from dl.caveonetworks.com (64.2.3.194.ptr.us.xo.net. [64.2.3.194]) by smtp.gmail.com with ESMTPSA id o9sm2156131igh.5.2015.09.22.17.00.10 (version=TLSv1 cipher=RC4-SHA bits=128/128); Tue, 22 Sep 2015 17:00:11 -0700 (PDT) Received: from dl.caveonetworks.com (localhost.localdomain [127.0.0.1]) by dl.caveonetworks.com (8.14.5/8.14.5) with ESMTP id t8N0093B013243; Tue, 22 Sep 2015 17:00:09 -0700 Received: (from ddaney@localhost) by dl.caveonetworks.com (8.14.5/8.14.5/Submit) id t8N009YN013242; Tue, 22 Sep 2015 17:00:09 -0700 From: David Daney To: linux-kernel@vger.kernel.org, Will Deacon , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, Marc Zyngier , Grant Likely , Thomas Gleixner , Jason Cooper Subject: [PATCH v2 1/3] Docs: dt: Add PCI MSI map bindings Date: Tue, 22 Sep 2015 17:00:04 -0700 Message-Id: <1442966406-13198-2-git-send-email-ddaney.cavm@gmail.com> X-Mailer: git-send-email 1.7.11.7 In-Reply-To: <1442966406-13198-1-git-send-email-ddaney.cavm@gmail.com> References: <1442966406-13198-1-git-send-email-ddaney.cavm@gmail.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20150922_170034_980583_CD069534 X-CRM114-Status: GOOD ( 22.41 ) X-Spam-Score: -2.7 (--) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: David Daney MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.1 required=5.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, FREEMAIL_FROM, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, T_DKIM_INVALID, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Mark Rutland Currently msi-parent is used by a few bindings to describe the relationship between a PCI root complex and a single MSI controller, but this property does not have a generic binding document. Additionally, msi-parent is insufficient to describe more complex relationships between MSI controllers and devices under a root complex, where devices may be able to target multiple MSI controllers, or where MSI controllers use (non-probeable) sideband information to distinguish devices. This patch adds a generic binding for mapping PCI devices to MSI controllers. This document covers msi-parent, and a new msi-map property (specific to PCI*) which may be used to map devices (identified by their Requester ID) to sideband data for each MSI controller that they may target. Signed-off-by: Mark Rutland Signed-off-by: David Daney Acked-by: Marc Zyngier --- Documentation/devicetree/bindings/pci/pci-msi.txt | 220 ++++++++++++++++++++++ 1 file changed, 220 insertions(+) create mode 100644 Documentation/devicetree/bindings/pci/pci-msi.txt diff --git a/Documentation/devicetree/bindings/pci/pci-msi.txt b/Documentation/devicetree/bindings/pci/pci-msi.txt new file mode 100644 index 0000000..9b3cc81 --- /dev/null +++ b/Documentation/devicetree/bindings/pci/pci-msi.txt @@ -0,0 +1,220 @@ +This document describes the generic device tree binding for describing the +relationship between PCI devices and MSI controllers. + +Each PCI device under a root complex is uniquely identified by its Requester ID +(AKA RID). A Requester ID is a triplet of a Bus number, Device number, and +Function number. + +For the purpose of this document, when treated as a numeric value, a RID is +formatted such that: + +* Bits [15:8] are the Bus number. +* Bits [7:3] are the Device number. +* Bits [2:0] are the Function number. +* Any other bits required for padding must be zero. + +MSIs may be distinguished in part through the use of sideband data accompanying +writes. In the case of PCI devices, this sideband data may be derived from the +Requester ID. A mechanism is required to associate a device with both the MSI +controllers it can address, and the sideband data that will be associated with +its writes to those controllers. + +For generic MSI bindings, see +Documentation/devicetree/bindings/interrupt-controller/msi.txt. + + +PCI root complex +================ + +Optional properties +------------------- + +- msi-map: Maps a Requester ID to an MSI controller and associated + msi-specifier data. The property is an arbitrary number of tuples of + (rid-base,msi-controller,msi-base,length), where: + + * rid-base is a single cell describing the first RID matched by the entry. + + * msi-controller is a single phandle to an MSI controller + + * msi-base is an msi-specifier describing the msi-specifier produced for the + first RID matched by the entry. + + * length is a single cell describing how many consecutive RIDs are matched + following the rid-base. + + Any RID r in the interval [rid-base, rid-base + length) is associated with + the listed msi-controller, with the msi-specifier (r - rid-base + msi-base). + +- msi-map-mask: A mask to be applied to each Requester ID prior to being mapped + to an msi-specifier per the msi-map property. + +- msi-parent: Describes the MSI parent of the root complex itself. Where + the root complex and MSI controller do not pass sideband data with MSI + writes, this property may be used to describe the MSI controller(s) + used by PCI devices under the root complex, if defined as such in the + binding for the root complex. + + +Example (1) +=========== + +/ { + #address-cells = <1>; + #size-cells = <1>; + + msi: msi-controller@a { + reg = <0xa 0x1>; + compatible = "vendor,some-controller"; + msi-controller; + #msi-cells = <1>; + }; + + pci: pci@f { + reg = <0xf 0x1>; + compatible = "vendor,pcie-root-complex"; + device_type = "pci"; + + /* + * The sideband data provided to the MSI controller is + * the RID, identity-mapped. + */ + msi-map = <0x0 &msi_a 0x0 0x10000>, + }; +}; + + +Example (2) +=========== + +/ { + #address-cells = <1>; + #size-cells = <1>; + + msi: msi-controller@a { + reg = <0xa 0x1>; + compatible = "vendor,some-controller"; + msi-controller; + #msi-cells = <1>; + }; + + pci: pci@f { + reg = <0xf 0x1>; + compatible = "vendor,pcie-root-complex"; + device_type = "pci"; + + /* + * The sideband data provided to the MSI controller is + * the RID, masked to only the device and function bits. + */ + msi-map = <0x0 &msi_a 0x0 0x100>, + msi-map-mask = <0xff> + }; +}; + + +Example (3) +=========== + +/ { + #address-cells = <1>; + #size-cells = <1>; + + msi: msi-controller@a { + reg = <0xa 0x1>; + compatible = "vendor,some-controller"; + msi-controller; + #msi-cells = <1>; + }; + + pci: pci@f { + reg = <0xf 0x1>; + compatible = "vendor,pcie-root-complex"; + device_type = "pci"; + + /* + * The sideband data provided to the MSI controller is + * the RID, but the high bit of the bus number is + * ignored. + */ + msi-map = <0x0000 &msi 0x0000 0x8000>, + <0x8000 &msi 0x0000 0x8000>; + }; +}; + + +Example (4) +=========== + +/ { + #address-cells = <1>; + #size-cells = <1>; + + msi: msi-controller@a { + reg = <0xa 0x1>; + compatible = "vendor,some-controller"; + msi-controller; + #msi-cells = <1>; + }; + + pci: pci@f { + reg = <0xf 0x1>; + compatible = "vendor,pcie-root-complex"; + device_type = "pci"; + + /* + * The sideband data provided to the MSI controller is + * the RID, but the high bit of the bus number is + * negated. + */ + msi-map = <0x0000 &msi 0x8000 0x8000>, + <0x8000 &msi 0x0000 0x8000>; + }; +}; + + +Example (5) +=========== + +/ { + #address-cells = <1>; + #size-cells = <1>; + + msi_a: msi-controller@a { + reg = <0xa 0x1>; + compatible = "vendor,some-controller"; + msi-controller; + #msi-cells = <1>; + }; + + msi_b: msi-controller@b { + reg = <0xb 0x1>; + compatible = "vendor,some-controller"; + msi-controller; + #msi-cells = <1>; + }; + + msi_c: msi-controller@c { + reg = <0xc 0x1>; + compatible = "vendor,some-controller"; + msi-controller; + #msi-cells = <1>; + }; + + pci: pci@c { + reg = <0xf 0x1>; + compatible = "vendor,pcie-root-complex"; + device_type = "pci"; + + /* + * The sideband data provided to MSI controller a is the + * RID, but the high bit of the bus number is negated. + * The sideband data provided to MSI controller b is the + * RID, identity-mapped. + * MSI controller c is not addressable. + */ + msi-map = <0x0000 &msi_a 0x8000 0x08000>, + <0x8000 &msi_a 0x0000 0x08000>, + <0x0000 &msi_b 0x0000 0x10000>; + }; +};