From patchwork Wed Feb 2 14:10:07 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jonathan Cameron X-Patchwork-Id: 12733029 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 D785EC433EF for ; Wed, 2 Feb 2022 14:17:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231190AbiBBORR (ORCPT ); Wed, 2 Feb 2022 09:17:17 -0500 Received: from frasgout.his.huawei.com ([185.176.79.56]:4630 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230171AbiBBORR (ORCPT ); Wed, 2 Feb 2022 09:17:17 -0500 Received: from fraeml709-chm.china.huawei.com (unknown [172.18.147.200]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4JpkJy4Kg1z67T9N; Wed, 2 Feb 2022 22:12:34 +0800 (CST) Received: from lhreml710-chm.china.huawei.com (10.201.108.61) by fraeml709-chm.china.huawei.com (10.206.15.37) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Wed, 2 Feb 2022 15:17:15 +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; Wed, 2 Feb 2022 14:17:14 +0000 From: Jonathan Cameron To: , =?utf-8?q?Alex_Benn=C3=A9e?= , Marcel Apfelbaum , "Michael S . Tsirkin" , Igor Mammedov CC: , Ben Widawsky , "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 v5 13/43] hw/pxb: Allow creation of a CXL PXB (host bridge) Date: Wed, 2 Feb 2022 14:10:07 +0000 Message-ID: <20220202141037.17352-14-Jonathan.Cameron@huawei.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220202141037.17352-1-Jonathan.Cameron@huawei.com> References: <20220202141037.17352-1-Jonathan.Cameron@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.122.247.231] X-ClientProxiedBy: lhreml743-chm.china.huawei.com (10.201.108.193) 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 This works like adding a typical pxb device, except the name is 'pxb-cxl' instead of 'pxb-pcie'. An example command line would be as follows: -device pxb-cxl,id=cxl.0,bus="pcie.0",bus_nr=1 A CXL PXB is backward compatible with PCIe. What this means in practice is that an operating system that is unaware of CXL should still be able to enumerate this topology as if it were PCIe. One can create multiple CXL PXB host bridges, but a host bridge can only be connected to the main root bus. Host bridges cannot appear elsewhere in the topology. Note that as of this patch, the ACPI tables needed for the host bridge (specifically, an ACPI object in _SB named ACPI0016 and the CEDT) aren't created. So while this patch internally creates it, it cannot be properly used by an operating system or other system software. Signed-off-by: Ben Widawsky Signed-off-by: Jonathan.Cameron --- v5: All in response to Alex's review (thanks!) - Moved pxb_dev_reset() to cxl realize function instead of doing it in the common code called from that function. - Fixed pxb_dev_reset() not being called in other paths due to it being registered in the wrong class_init. Note it was also broken so pulled a reference from the PXB_CXL_DEV to the host bridge back from patch 24 as we now need it here. hw/pci-bridge/pci_expander_bridge.c | 95 ++++++++++++++++++++++++++++- hw/pci/pci.c | 7 +++ include/hw/pci/pci.h | 6 ++ 3 files changed, 106 insertions(+), 2 deletions(-) diff --git a/hw/pci-bridge/pci_expander_bridge.c b/hw/pci-bridge/pci_expander_bridge.c index a6caa1e7b5..c7a28c7b2e 100644 --- a/hw/pci-bridge/pci_expander_bridge.c +++ b/hw/pci-bridge/pci_expander_bridge.c @@ -17,6 +17,7 @@ #include "hw/pci/pci_host.h" #include "hw/qdev-properties.h" #include "hw/pci/pci_bridge.h" +#include "hw/cxl/cxl.h" #include "qemu/range.h" #include "qemu/error-report.h" #include "qemu/module.h" @@ -56,6 +57,17 @@ DECLARE_INSTANCE_CHECKER(PXBDev, PXB_DEV, DECLARE_INSTANCE_CHECKER(PXBDev, PXB_PCIE_DEV, TYPE_PXB_PCIE_DEVICE) +#define TYPE_PXB_CXL_DEVICE "pxb-cxl" +DECLARE_INSTANCE_CHECKER(PXBDev, PXB_CXL_DEV, + TYPE_PXB_CXL_DEVICE) + +typedef struct CXLHost { + PCIHostState parent_obj; + + CXLComponentState cxl_cstate; +} CXLHost; + + struct PXBDev { /*< private >*/ PCIDevice parent_obj; @@ -64,10 +76,18 @@ struct PXBDev { uint8_t bus_nr; uint16_t numa_node; bool bypass_iommu; + struct cxl_dev { + CXLHost *cxl_host_bridge; + } cxl; }; static PXBDev *convert_to_pxb(PCIDevice *dev) { + /* A CXL PXB's parent bus is PCIe, so the normal check won't work */ + if (object_dynamic_cast(OBJECT(dev), TYPE_PXB_CXL_DEVICE)) { + return PXB_CXL_DEV(dev); + } + return pci_bus_is_express(pci_get_bus(dev)) ? PXB_PCIE_DEV(dev) : PXB_DEV(dev); } @@ -76,6 +96,9 @@ static GList *pxb_dev_list; #define TYPE_PXB_HOST "pxb-host" +#define TYPE_PXB_CXL_HOST "pxb-cxl-host" +#define PXB_CXL_HOST(obj) OBJECT_CHECK(CXLHost, (obj), TYPE_PXB_CXL_HOST) + static int pxb_bus_num(PCIBus *bus) { PXBDev *pxb = convert_to_pxb(bus->parent_dev); @@ -112,11 +135,20 @@ static const TypeInfo pxb_pcie_bus_info = { .class_init = pxb_bus_class_init, }; +static const TypeInfo pxb_cxl_bus_info = { + .name = TYPE_PXB_CXL_BUS, + .parent = TYPE_CXL_BUS, + .instance_size = sizeof(PXBBus), + .class_init = pxb_bus_class_init, +}; + static const char *pxb_host_root_bus_path(PCIHostState *host_bridge, PCIBus *rootbus) { - PXBBus *bus = pci_bus_is_express(rootbus) ? - PXB_PCIE_BUS(rootbus) : PXB_BUS(rootbus); + PXBBus *bus = pci_bus_is_cxl(rootbus) ? + PXB_CXL_BUS(rootbus) : + pci_bus_is_express(rootbus) ? PXB_PCIE_BUS(rootbus) : + PXB_BUS(rootbus); snprintf(bus->bus_path, 8, "0000:%02x", pxb_bus_num(rootbus)); return bus->bus_path; @@ -218,6 +250,16 @@ static int pxb_map_irq_fn(PCIDevice *pci_dev, int pin) return pin - PCI_SLOT(pxb->devfn); } +static void pxb_dev_reset(DeviceState *dev) +{ + CXLHost *cxl = PXB_CXL_DEV(dev)->cxl.cxl_host_bridge; + CXLComponentState *cxl_cstate = &cxl->cxl_cstate; + uint32_t *reg_state = cxl_cstate->crb.cache_mem_registers; + + cxl_component_register_init_common(reg_state, CXL2_ROOT_PORT); + ARRAY_FIELD_DP32(reg_state, CXL_HDM_DECODER_CAPABILITY, TARGET_COUNT, 8); +} + static gint pxb_compare(gconstpointer a, gconstpointer b) { const PXBDev *pxb_a = a, *pxb_b = b; @@ -258,6 +300,7 @@ static void pxb_dev_realize_common(PCIDevice *dev, enum BusType type, } else if (type == CXL) { bus = pci_root_bus_new(ds, dev_name, NULL, NULL, 0, TYPE_PXB_CXL_BUS); bus->flags |= PCI_BUS_CXL; + PXB_CXL_DEV(dev)->cxl.cxl_host_bridge = PXB_CXL_HOST(ds); } else { bus = pci_root_bus_new(ds, "pxb-internal", NULL, NULL, 0, TYPE_PXB_BUS); bds = qdev_new("pci-bridge"); @@ -290,6 +333,7 @@ static void pxb_dev_realize_common(PCIDevice *dev, enum BusType type, pci_config_set_class(dev->config, PCI_CLASS_BRIDGE_HOST); pxb_dev_list = g_list_insert_sorted(pxb_dev_list, pxb, pxb_compare); + return; err_register_bus: @@ -389,13 +433,60 @@ static const TypeInfo pxb_pcie_dev_info = { }, }; +static void pxb_cxl_dev_realize(PCIDevice *dev, Error **errp) +{ + /* A CXL PXB's parent bus is still PCIe */ + if (!pci_bus_is_express(pci_get_bus(dev))) { + error_setg(errp, "pxb-cxl devices cannot reside on a PCI bus"); + return; + } + + pxb_dev_realize_common(dev, CXL, errp); + pxb_dev_reset(DEVICE(dev)); +} + +static void pxb_cxl_dev_class_init(ObjectClass *klass, void *data) +{ + DeviceClass *dc = DEVICE_CLASS(klass); + PCIDeviceClass *k = PCI_DEVICE_CLASS(klass); + + k->realize = pxb_cxl_dev_realize; + k->exit = pxb_dev_exitfn; + /* + * XXX: These types of bridges don't actually show up in the hierarchy so + * vendor, device, class, etc. ids are intentionally left out. + */ + + dc->desc = "CXL Host Bridge"; + device_class_set_props(dc, pxb_dev_properties); + set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories); + + /* Host bridges aren't hotpluggable. FIXME: spec reference */ + dc->hotpluggable = false; + dc->reset = pxb_dev_reset; +} + +static const TypeInfo pxb_cxl_dev_info = { + .name = TYPE_PXB_CXL_DEVICE, + .parent = TYPE_PCI_DEVICE, + .instance_size = sizeof(PXBDev), + .class_init = pxb_cxl_dev_class_init, + .interfaces = + (InterfaceInfo[]){ + { INTERFACE_CONVENTIONAL_PCI_DEVICE }, + {}, + }, +}; + static void pxb_register_types(void) { type_register_static(&pxb_bus_info); type_register_static(&pxb_pcie_bus_info); + type_register_static(&pxb_cxl_bus_info); type_register_static(&pxb_host_info); type_register_static(&pxb_dev_info); type_register_static(&pxb_pcie_dev_info); + type_register_static(&pxb_cxl_dev_info); } type_init(pxb_register_types) diff --git a/hw/pci/pci.c b/hw/pci/pci.c index 474ea98c1d..cafebf6f59 100644 --- a/hw/pci/pci.c +++ b/hw/pci/pci.c @@ -229,6 +229,12 @@ static const TypeInfo pcie_bus_info = { .class_init = pcie_bus_class_init, }; +static const TypeInfo cxl_bus_info = { + .name = TYPE_CXL_BUS, + .parent = TYPE_PCIE_BUS, + .class_init = pcie_bus_class_init, +}; + static PCIBus *pci_find_bus_nr(PCIBus *bus, int bus_num); static void pci_update_mappings(PCIDevice *d); static void pci_irq_handler(void *opaque, int irq_num, int level); @@ -2892,6 +2898,7 @@ static void pci_register_types(void) { type_register_static(&pci_bus_info); type_register_static(&pcie_bus_info); + type_register_static(&cxl_bus_info); type_register_static(&conventional_pci_interface_info); type_register_static(&cxl_interface_info); type_register_static(&pcie_interface_info); diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h index 908896ebe8..97cbbad375 100644 --- a/include/hw/pci/pci.h +++ b/include/hw/pci/pci.h @@ -409,6 +409,7 @@ typedef PCIINTxRoute (*pci_route_irq_fn)(void *opaque, int pin); #define TYPE_PCI_BUS "PCI" OBJECT_DECLARE_TYPE(PCIBus, PCIBusClass, PCI_BUS) #define TYPE_PCIE_BUS "PCIE" +#define TYPE_CXL_BUS "CXL" typedef void (*pci_bus_dev_fn)(PCIBus *b, PCIDevice *d, void *opaque); typedef void (*pci_bus_fn)(PCIBus *b, void *opaque); @@ -768,6 +769,11 @@ static inline void pci_irq_pulse(PCIDevice *pci_dev) pci_irq_deassert(pci_dev); } +static inline int pci_is_cxl(const PCIDevice *d) +{ + return d->cap_present & QEMU_PCIE_CAP_CXL; +} + static inline int pci_is_express(const PCIDevice *d) { return d->cap_present & QEMU_PCI_CAP_EXPRESS;