From patchwork Mon Apr 4 15:14:12 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Jonathan Cameron X-Patchwork-Id: 12800409 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 169B0C433F5 for ; Mon, 4 Apr 2022 15:20:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1378000AbiDDPWo (ORCPT ); Mon, 4 Apr 2022 11:22:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35190 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1378506AbiDDPWn (ORCPT ); Mon, 4 Apr 2022 11:22:43 -0400 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 15B703C4A6 for ; Mon, 4 Apr 2022 08:20:47 -0700 (PDT) Received: from fraeml744-chm.china.huawei.com (unknown [172.18.147.207]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4KXDv90zy5z67Ljg; Mon, 4 Apr 2022 23:18:45 +0800 (CST) Received: from lhreml710-chm.china.huawei.com (10.201.108.61) by fraeml744-chm.china.huawei.com (10.206.15.225) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Mon, 4 Apr 2022 17:20:45 +0200 Received: from SecurePC-101-06.china.huawei.com (10.122.247.231) by lhreml710-chm.china.huawei.com (10.201.108.61) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Mon, 4 Apr 2022 16:20:44 +0100 From: Jonathan Cameron To: , , =?utf-8?q?Alex_Benn?= =?utf-8?q?=C3=A9e?= , Marcel Apfelbaum , "Michael S . Tsirkin" , Igor Mammedov , Markus Armbruster , "Mark Cave-Ayland" , Adam Manzanares CC: , Ben Widawsky , "Peter Maydell" , Shameerali Kolothum Thodi , =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= , Peter Xu , David Hildenbrand , Paolo Bonzini , Saransh Gupta1 , Shreyas Shah , Chris Browy , "Samarth Saxena" , Dan Williams , "k . jensen @ samsung . com" , Tong Zhang , , Alison Schofield Subject: [PATCH v9 12/45] hw/pci/cxl: Create a CXL bus type Date: Mon, 4 Apr 2022 16:14:12 +0100 Message-ID: <20220404151445.10955-13-Jonathan.Cameron@huawei.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220404151445.10955-1-Jonathan.Cameron@huawei.com> References: <20220404151445.10955-1-Jonathan.Cameron@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.122.247.231] X-ClientProxiedBy: lhreml717-chm.china.huawei.com (10.201.108.68) To lhreml710-chm.china.huawei.com (10.201.108.61) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-cxl@vger.kernel.org From: Ben Widawsky The easiest way to differentiate a CXL bus, and a PCIE bus is using a flag. A CXL bus, in hardware, is backward compatible with PCIE, and therefore the code tries pretty hard to keep them in sync as much as possible. The other way to implement this would be to try to cast the bus to the correct type. This is less code and useful for debugging via simply looking at the flags. Signed-off-by: Ben Widawsky Signed-off-by: Jonathan Cameron Reviewed-by: Alex Bennée --- hw/pci-bridge/pci_expander_bridge.c | 9 ++++++++- include/hw/pci/pci_bus.h | 7 +++++++ 2 files changed, 15 insertions(+), 1 deletion(-) diff --git a/hw/pci-bridge/pci_expander_bridge.c b/hw/pci-bridge/pci_expander_bridge.c index d4514227a8..a6caa1e7b5 100644 --- a/hw/pci-bridge/pci_expander_bridge.c +++ b/hw/pci-bridge/pci_expander_bridge.c @@ -24,7 +24,7 @@ #include "hw/boards.h" #include "qom/object.h" -enum BusType { PCI, PCIE }; +enum BusType { PCI, PCIE, CXL }; #define TYPE_PXB_BUS "pxb-bus" typedef struct PXBBus PXBBus; @@ -35,6 +35,10 @@ DECLARE_INSTANCE_CHECKER(PXBBus, PXB_BUS, DECLARE_INSTANCE_CHECKER(PXBBus, PXB_PCIE_BUS, TYPE_PXB_PCIE_BUS) +#define TYPE_PXB_CXL_BUS "pxb-cxl-bus" +DECLARE_INSTANCE_CHECKER(PXBBus, PXB_CXL_BUS, + TYPE_PXB_CXL_BUS) + struct PXBBus { /*< private >*/ PCIBus parent_obj; @@ -251,6 +255,9 @@ static void pxb_dev_realize_common(PCIDevice *dev, enum BusType type, ds = qdev_new(TYPE_PXB_HOST); if (type == PCIE) { bus = pci_root_bus_new(ds, dev_name, NULL, NULL, 0, TYPE_PXB_PCIE_BUS); + } else if (type == CXL) { + bus = pci_root_bus_new(ds, dev_name, NULL, NULL, 0, TYPE_PXB_CXL_BUS); + bus->flags |= PCI_BUS_CXL; } else { bus = pci_root_bus_new(ds, "pxb-internal", NULL, NULL, 0, TYPE_PXB_BUS); bds = qdev_new("pci-bridge"); diff --git a/include/hw/pci/pci_bus.h b/include/hw/pci/pci_bus.h index 347440d42c..eb94e7e85c 100644 --- a/include/hw/pci/pci_bus.h +++ b/include/hw/pci/pci_bus.h @@ -24,6 +24,8 @@ enum PCIBusFlags { PCI_BUS_IS_ROOT = 0x0001, /* PCIe extended configuration space is accessible on this bus */ PCI_BUS_EXTENDED_CONFIG_SPACE = 0x0002, + /* This is a CXL Type BUS */ + PCI_BUS_CXL = 0x0004, }; struct PCIBus { @@ -53,6 +55,11 @@ struct PCIBus { Notifier machine_done; }; +static inline bool pci_bus_is_cxl(PCIBus *bus) +{ + return !!(bus->flags & PCI_BUS_CXL); +} + static inline bool pci_bus_is_root(PCIBus *bus) { return !!(bus->flags & PCI_BUS_IS_ROOT);