From patchwork Mon Jan 24 17:16:35 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Jonathan Cameron X-Patchwork-Id: 12722478 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 9034FC433EF for ; Mon, 24 Jan 2022 17:23:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241352AbiAXRXO (ORCPT ); Mon, 24 Jan 2022 12:23:14 -0500 Received: from frasgout.his.huawei.com ([185.176.79.56]:4457 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244428AbiAXRXN (ORCPT ); Mon, 24 Jan 2022 12:23:13 -0500 Received: from fraeml701-chm.china.huawei.com (unknown [172.18.147.201]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4JjGtB3fpPz67ws7; Tue, 25 Jan 2022 01:18:58 +0800 (CST) Received: from lhreml710-chm.china.huawei.com (10.201.108.61) by fraeml701-chm.china.huawei.com (10.206.15.50) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2308.21; Mon, 24 Jan 2022 18:23:11 +0100 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 15.1.2308.21; Mon, 24 Jan 2022 17:23:11 +0000 From: Jonathan Cameron To: , Marcel Apfelbaum , "Michael S . Tsirkin" , Igor Mammedov CC: , Ben Widawsky , =?utf-8?q?Alex_Benn=C3=A9e?= , Peter Maydell , , Shameerali Kolothum Thodi , =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= , Saransh Gupta1 , Shreyas Shah , Chris Browy , Samarth Saxena , "Dan Williams" Subject: [PATCH v4 12/42] hw/pci/cxl: Create a CXL bus type Date: Mon, 24 Jan 2022 17:16:35 +0000 Message-ID: <20220124171705.10432-13-Jonathan.Cameron@huawei.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220124171705.10432-1-Jonathan.Cameron@huawei.com> References: <20220124171705.10432-1-Jonathan.Cameron@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.122.247.231] X-ClientProxiedBy: lhreml740-chm.china.huawei.com (10.201.108.190) 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);