// SPDX-License-Identifier: GPL-2.0-only /* Copyright(c) 2020 Intel Corporation. All rights reserved. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "core.h" /** * DOC: cxl core * * The CXL core provides a set of interfaces that can be consumed by CXL aware * drivers. The interfaces allow for creation, modification, and destruction of * regions, memory devices, ports, and decoders. CXL aware drivers must register * with the CXL core via these interfaces in order to be able to participate in * cross-device interleave coordination. The CXL core also establishes and * maintains the bridge to the nvdimm subsystem. * * CXL core introduces sysfs hierarchy to control the devices that are * instantiated by the core. */ /* * All changes to the interleave configuration occur with this lock held * for write. */ DECLARE_RWSEM(cxl_region_rwsem); static DEFINE_IDA(cxl_port_ida); static DEFINE_XARRAY(cxl_root_buses); int cxl_num_decoders_committed(struct cxl_port *port) { lockdep_assert_held(&cxl_region_rwsem); return port->commit_end + 1; } static ssize_t devtype_show(struct device *dev, struct device_attribute *attr, char *buf) { return sysfs_emit(buf, "%s\n", dev->type->name); } static DEVICE_ATTR_RO(devtype); static int cxl_device_id(const struct device *dev) { if (dev->type == &cxl_nvdimm_bridge_type) return CXL_DEVICE_NVDIMM_BRIDGE; if (dev->type == &cxl_nvdimm_type) return CXL_DEVICE_NVDIMM; if (dev->type == CXL_PMEM_REGION_TYPE()) return CXL_DEVICE_PMEM_REGION; if (dev->type == CXL_DAX_REGION_TYPE()) return CXL_DEVICE_DAX_REGION; if (is_cxl_port(dev)) { if (is_cxl_root(to_cxl_port(dev))) return CXL_DEVICE_ROOT; return CXL_DEVICE_PORT; } if (is_cxl_memdev(dev)) return CXL_DEVICE_MEMORY_EXPANDER; if (dev->type == CXL_REGION_TYPE()) return CXL_DEVICE_REGION; if (dev->type == &cxl_pmu_type) return CXL_DEVICE_PMU; return 0; } static ssize_t modalias_show(struct device *dev, struct device_attribute *attr, char *buf) { return sysfs_emit(buf, CXL_MODALIAS_FMT "\n", cxl_device_id(dev)); } static DEVICE_ATTR_RO(modalias); static struct attribute *cxl_base_attributes[] = { &dev_attr_devtype.attr, &dev_attr_modalias.attr, NULL, }; struct attribute_group cxl_base_attribute_group = { .attrs = cxl_base_attributes, }; static ssize_t start_show(struct device *dev, struct device_attribute *attr, char *buf) { struct cxl_decoder *cxld = to_cxl_decoder(dev); return sysfs_emit(buf, "%#llx\n", cxld->hpa_range.start); } static DEVICE_ATTR_ADMIN_RO(start); static ssize_t size_show(struct device *dev, struct device_attribute *attr, char *buf) { struct cxl_decoder *cxld = to_cxl_decoder(dev); return sysfs_emit(buf, "%#llx\n", range_len(&cxld->hpa_range)); } static DEVICE_ATTR_RO(size); #define CXL_DECODER_FLAG_ATTR(name, flag) \ static ssize_t name##_show(struct device *dev, \ struct device_attribute *attr, char *buf) \ { \ struct cxl_decoder *cxld = to_cxl_decoder(dev); \ \ return sysfs_emit(buf, "%s\n", \ (cxld->flags & (flag)) ? "1" : "0"); \ } \ static DEVICE_ATTR_RO(name) CXL_DECODER_FLAG_ATTR(cap_pmem, CXL_DECODER_F_PMEM); CXL_DECODER_FLAG_ATTR(cap_ram, CXL_DECODER_F_RAM); CXL_DECODER_FLAG_ATTR(cap_type2, CXL_DECODER_F_TYPE2); CXL_DECODER_FLAG_ATTR(cap_type3, CXL_DECODER_F_TYPE3); CXL_DECODER_FLAG_ATTR(locked, CXL_DECODER_F_LOCK); static ssize_t target_type_show(struct device *dev, struct device_attribute *attr, char *buf) { struct cxl_decoder *cxld = to_cxl_decoder(dev); switch (cxld->target_type) { case CXL_DECODER_DEVMEM: return sysfs_emit(buf, "accelerator\n"); case CXL_DECODER_HOSTONLYMEM: return sysfs_emit(buf, "expander\n"); } return -ENXIO; } static DEVICE_ATTR_RO(target_type); static ssize_t emit_target_list(struct cxl_switch_decoder *cxlsd, char *buf) { struct cxl_decoder *cxld = &cxlsd->cxld; ssize_t offset = 0; int i, rc = 0; for (i = 0; i < cxld->interleave_ways; i++) { struct cxl_dport *dport = cxlsd->target[i]; struct cxl_dport *next = NULL; if (!dport) break; if (i + 1 < cxld->interleave_ways) next = cxlsd->target[i + 1]; rc = sysfs_emit_at(buf, offset, "%d%s", dport->port_id, next ? "," : ""); if (rc < 0) return rc; offset += rc; } return offset; } static ssize_t target_list_show(struct device *dev, struct device_attribute *attr, char *buf) { struct cxl_switch_decoder *cxlsd = to_cxl_switch_decoder(dev); ssize_t offset; int rc; guard(rwsem_read)(&cxl_region_rwsem); rc = emit_target_list(cxlsd, buf); if (rc < 0) return rc; offset = rc; rc = sysfs_emit_at(buf, offset, "\n"); if (rc < 0) return rc; return offset + rc; } static DEVICE_ATTR_RO(target_list); static ssize_t mode_show(struct device *dev, struct device_attribute *attr, char *buf) { struct cxl_endpoint_decoder *cxled = to_cxl_endpoint_decoder(dev); return sysfs_emit(buf, "%s\n", cxl_decoder_mode_name(cxled->mode)); } static ssize_t mode_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t len) { struct cxl_endpoint_decoder *cxled = to_cxl_endpoint_decoder(dev); enum cxl_decoder_mode mode; ssize_t rc; if (sysfs_streq(buf, "pmem")) mode = CXL_DECODER_PMEM; else if (sysfs_streq(buf, "ram")) mode = CXL_DECODER_RAM; else return -EINVAL; rc = cxl_dpa_set_mode(cxled, mode); if (rc) return rc; return len; } static DEVICE_ATTR_RW(mode); static ssize_t dpa_resource_show(struct device *dev, struct device_attribute *attr, char *buf) { struct cxl_endpoint_decoder *cxled = to_cxl_endpoint_decoder(dev); guard(rwsem_read)(&cxl_dpa_rwsem); return sysfs_emit(buf, "%#llx\n", (u64)cxl_dpa_resource_start(cxled)); } static DEVICE_ATTR_RO(dpa_resource); static ssize_t dpa_size_show(struct device *dev, struct device_attribute *attr, char *buf) { struct cxl_endpoint_decoder *cxled = to_cxl_endpoint_decoder(dev); resource_size_t size = cxl_dpa_size(cxled); return sysfs_emit(buf, "%pa\n", &size); } static ssize_t dpa_size_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t len) { struct cxl_endpoint_decoder *cxled = to_cxl_endpoint_decoder(dev); unsigned long long size; ssize_t rc; rc = kstrtoull(buf, 0, &size); if (rc) return rc; if (!IS_ALIGNED(size, SZ_256M)) return -EINVAL; rc = cxl_dpa_free(cxled); if (rc) return rc; if (size == 0) return len; rc = cxl_dpa_alloc(cxled, size); if (rc) return rc; return len; } static DEVICE_ATTR_RW(dpa_size); static ssize_t interleave_granularity_show(struct device *dev, struct device_attribute *attr, char *buf) { struct cxl_decoder *cxld = to_cxl_decoder(dev); return sysfs_emit(buf, "%d\n", cxld->interleave_granularity); } static DEVICE_ATTR_RO(interleave_granularity); static ssize_t interleave_ways_show(struct device *dev, struct device_attribute *attr, char *buf) { struct cxl_decoder *cxld = to_cxl_decoder(dev); return sysfs_emit(buf, "%d\n", cxld->interleave_ways); } static DEVICE_ATTR_RO(interleave_ways); static ssize_t qos_class_show(struct device *dev, struct device_attribute *attr, char *buf) { struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(dev); return sysfs_emit(buf, "%d\n", cxlrd->qos_class); } static DEVICE_ATTR_RO(qos_class); static struct attribute *cxl_decoder_base_attrs[] = { &dev_attr_start.attr, &dev_attr_size.attr, &dev_attr_locked.attr, &dev_attr_interleave_granularity.attr, &dev_attr_interleave_ways.attr, NULL, }; static struct attribute_group cxl_decoder_base_attribute_group = { .attrs = cxl_decoder_base_attrs, }; static struct attribute *cxl_decoder_root_attrs[] = { &dev_attr_cap_pmem.attr, &dev_attr_cap_ram.attr, &dev_attr_cap_type2.attr, &dev_attr_cap_type3.attr, &dev_attr_target_list.attr, &dev_attr_qos_class.attr, SET_CXL_REGION_ATTR(create_pmem_region) SET_CXL_REGION_ATTR(create_ram_region) SET_CXL_REGION_ATTR(delete_region) NULL, }; static bool can_create_pmem(struct cxl_root_decoder *cxlrd) { unsigned long flags = CXL_DECODER_F_TYPE3 | CXL_DECODER_F_PMEM; return (cxlrd->cxlsd.cxld.flags & flags) == flags; } static bool can_create_ram(struct cxl_root_decoder *cxlrd) { unsigned long flags = CXL_DECODER_F_TYPE3 | CXL_DECODER_F_RAM; return (cxlrd->cxlsd.cxld.flags & flags) == flags; } static umode_t cxl_root_decoder_visible(struct kobject *kobj, struct attribute *a, int n) { struct device *dev = kobj_to_dev(kobj); struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(dev); if (a == CXL_REGION_ATTR(create_pmem_region) && !can_create_pmem(cxlrd)) return 0; if (a == CXL_REGION_ATTR(create_ram_region) && !can_create_ram(cxlrd)) return 0; if (a == CXL_REGION_ATTR(delete_region) && !(can_create_pmem(cxlrd) || can_create_ram(cxlrd))) return 0; return a->mode; } static struct attribute_group cxl_decoder_root_attribute_group = { .attrs = cxl_decoder_root_attrs, .is_visible = cxl_root_decoder_visible, }; static const struct attribute_group *cxl_decoder_root_attribute_groups[] = { &cxl_decoder_root_attribute_group, &cxl_decoder_base_attribute_group, &cxl_base_attribute_group, NULL, }; static struct attribute *cxl_decoder_switch_attrs[] = { &dev_attr_target_type.attr, &dev_attr_target_list.attr, SET_CXL_REGION_ATTR(region) NULL, }; static struct attribute_group cxl_decoder_switch_attribute_group = { .attrs = cxl_decoder_switch_attrs, }; static const struct attribute_group *cxl_decoder_switch_attribute_groups[] = { &cxl_decoder_switch_attribute_group, &cxl_decoder_base_attribute_group, &cxl_base_attribute_group, NULL, }; static struct attribute *cxl_decoder_endpoint_attrs[] = { &dev_attr_target_type.attr, &dev_attr_mode.attr, &dev_attr_dpa_size.attr, &dev_attr_dpa_resource.attr, SET_CXL_REGION_ATTR(region) NULL, }; static struct attribute_group cxl_decoder_endpoint_attribute_group = { .attrs = cxl_decoder_endpoint_attrs, }; static const struct attribute_group *cxl_decoder_endpoint_attribute_groups[] = { &cxl_decoder_base_attribute_group, &cxl_decoder_endpoint_attribute_group, &cxl_base_attribute_group, NULL, }; static void __cxl_decoder_release(struct cxl_decoder *cxld) { struct cxl_port *port = to_cxl_port(cxld->dev.parent); ida_free(&port->decoder_ida, cxld->id); put_device(&port->dev); } static void cxl_endpoint_decoder_release(struct device *dev) { struct cxl_endpoint_decoder *cxled = to_cxl_endpoint_decoder(dev); __cxl_decoder_release(&cxled->cxld); kfree(cxled); } static void cxl_switch_decoder_release(struct device *dev) { struct cxl_switch_decoder *cxlsd = to_cxl_switch_decoder(dev); __cxl_decoder_release(&cxlsd->cxld); kfree(cxlsd); } struct cxl_root_decoder *to_cxl_root_decoder(struct device *dev) { if (dev_WARN_ONCE(dev, !is_root_decoder(dev), "not a cxl_root_decoder device\n")) return NULL; return container_of(dev, struct cxl_root_decoder, cxlsd.cxld.dev); } EXPORT_SYMBOL_NS_GPL(to_cxl_root_decoder, CXL); static void cxl_root_decoder_release(struct device *dev) { struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(dev); if (atomic_read(&cxlrd->region_id) >= 0) memregion_free(atomic_read(&cxlrd->region_id)); __cxl_decoder_release(&cxlrd->cxlsd.cxld); kfree(cxlrd); } static const struct device_type cxl_decoder_endpoint_type = { .name = "cxl_decoder_endpoint", .release = cxl_endpoint_decoder_release, .groups = cxl_decoder_endpoint_attribute_groups, }; static const struct device_type cxl_decoder_switch_type = { .name = "cxl_decoder_switch", .release = cxl_switch_decoder_release, .groups = cxl_decoder_switch_attribute_groups, }; static const struct device_type cxl_decoder_root_type = { .name = "cxl_decoder_root", .release = cxl_root_decoder_release, .groups = cxl_decoder_root_attribute_groups, }; bool is_endpoint_decoder(struct device *dev) { return dev->type == &cxl_decoder_endpoint_type; } EXPORT_SYMBOL_NS_GPL(is_endpoint_decoder, CXL); bool is_root_decoder(struct device *dev) { return dev->type == &cxl_decoder_root_type; } EXPORT_SYMBOL_NS_GPL(is_root_decoder, CXL); bool is_switch_decoder(struct device *dev) { return is_root_decoder(dev) || dev->type == &cxl_decoder_switch_type; } EXPORT_SYMBOL_NS_GPL(is_switch_decoder, CXL); struct cxl_decoder *to_cxl_decoder(struct device *dev) { if (dev_WARN_ONCE(dev, !is_switch_decoder(dev) && !is_endpoint_decoder(dev), "not a cxl_decoder device\n")) return NULL; return container_of(dev, struct cxl_decoder, dev); } EXPORT_SYMBOL_NS_GPL(to_cxl_decoder, CXL); struct cxl_endpoint_decoder *to_cxl_endpoint_decoder(struct device *dev) { if (dev_WARN_ONCE(dev, !is_endpoint_decoder(dev), "not a cxl_endpoint_decoder device\n")) return NULL; return container_of(dev, struct cxl_endpoint_decoder, cxld.dev); } EXPORT_SYMBOL_NS_GPL(to_cxl_endpoint_decoder, CXL); struct cxl_switch_decoder *to_cxl_switch_decoder(struct device *dev) { if (dev_WARN_ONCE(dev, !is_switch_decoder(dev), "not a cxl_switch_decoder device\n")) return NULL; return container_of(dev, struct cxl_switch_decoder, cxld.dev); } EXPORT_SYMBOL_NS_GPL(to_cxl_switch_decoder, CXL); static void cxl_ep_release(struct cxl_ep *ep) { put_device(ep->ep); kfree(ep); } static void cxl_ep_remove(struct cxl_port *port, struct cxl_ep *ep) { if (!ep) return; xa_erase(&port->endpoints, (unsigned long) ep->ep); cxl_ep_release(ep); } static void cxl_port_release(struct device *dev) { struct cxl_port *port = to_cxl_port(dev); unsigned long index; struct cxl_ep *ep; xa_for_each(&port->endpoints, index, ep) cxl_ep_remove(port, ep); xa_destroy(&port->endpoints); xa_destroy(&port->dports); xa_destroy(&port->regions); ida_free(&cxl_port_ida, port->id); if (is_cxl_root(port)) kfree(to_cxl_root(port)); else kfree(port); } static ssize_t decoders_committed_show(struct device *dev, struct device_attribute *attr, char *buf) { struct cxl_port *port = to_cxl_port(dev); int rc; down_read(&cxl_region_rwsem); rc = sysfs_emit(buf, "%d\n", cxl_num_decoders_committed(port)); up_read(&cxl_region_rwsem); return rc; } static DEVICE_ATTR_RO(decoders_committed); static struct attribute *cxl_port_attrs[] = { &dev_attr_decoders_committed.attr, NULL, }; static struct attribute_group cxl_port_attribute_group = { .attrs = cxl_port_attrs, }; static const struct attribute_group *cxl_port_attribute_groups[] = { &cxl_base_attribute_group, &cxl_port_attribute_group, NULL, }; static const struct device_type cxl_port_type = { .name = "cxl_port", .release = cxl_port_release, .groups = cxl_port_attribute_groups, }; bool is_cxl_port(const struct device *dev) { return dev->type == &cxl_port_type; } EXPORT_SYMBOL_NS_GPL(is_cxl_port, CXL); struct cxl_port *to_cxl_port(const struct device *dev) { if (dev_WARN_ONCE(dev, dev->type != &cxl_port_type, "not a cxl_port device\n")) return NULL; return container_of(dev, struct cxl_port, dev); } EXPORT_SYMBOL_NS_GPL(to_cxl_port, CXL); static void unregister_port(void *_port) { struct cxl_port *port = _port; struct cxl_port *parent; struct device *lock_dev; if (is_cxl_root(port)) parent = NULL; else parent = to_cxl_port(port->dev.parent); /* * CXL root port's and the first level of ports are unregistered * under the platform firmware device lock, all other ports are * unregistered while holding their parent port lock. */ if (!parent) lock_dev = port->uport_dev; else if (is_cxl_root(parent)) lock_dev = parent->uport_dev; else lock_dev = &parent->dev; device_lock_assert(lock_dev); port->dead = true; device_unregister(&port->dev); } static void cxl_unlink_uport(void *_port) { struct cxl_port *port = _port; sysfs_remove_link(&port->dev.kobj, "uport"); } static int devm_cxl_link_uport(struct device *host, struct cxl_port *port) { int rc; rc = sysfs_create_link(&port->dev.kobj, &port->uport_dev->kobj, "uport"); if (rc) return rc; return devm_add_action_or_reset(host, cxl_unlink_uport, port); } static void cxl_unlink_parent_dport(void *_port) { struct cxl_port *port = _port; sysfs_remove_link(&port->dev.kobj, "parent_dport"); } static int devm_cxl_link_parent_dport(struct device *host, struct cxl_port *port, struct cxl_dport *parent_dport) { int rc; if (!parent_dport) return 0; rc = sysfs_create_link(&port->dev.kobj, &parent_dport->dport_dev->kobj, "parent_dport"); if (rc) return rc; return devm_add_action_or_reset(host, cxl_unlink_parent_dport, port); } static struct lock_class_key cxl_port_key; static struct cxl_port *cxl_port_alloc(struct device *uport_dev, struct cxl_dport *parent_dport) { struct cxl_root *cxl_root __free(kfree) = NULL; struct cxl_port *port, *_port __free(kfree) = NULL; struct device *dev; int rc; /* No parent_dport, root cxl_port */ if (!parent_dport) { cxl_root = kzalloc(sizeof(*cxl_root), GFP_KERNEL); if (!cxl_root) return ERR_PTR(-ENOMEM); } else { _port = kzalloc(sizeof(*port), GFP_KERNEL); if (!_port) return ERR_PTR(-ENOMEM); } rc = ida_alloc(&cxl_port_ida, GFP_KERNEL); if (rc < 0) return ERR_PTR(rc); if (cxl_root) port = &no_free_ptr(cxl_root)->port; else port = no_free_ptr(_port); port->id = rc; port->uport_dev = uport_dev; /* * The top-level cxl_port "cxl_root" does not have a cxl_port as * its parent and it does not have any corresponding component * registers as its decode is described by a fixed platform * description. */ dev = &port->dev; if (parent_dport) { struct cxl_port *parent_port = parent_dport->port; struct cxl_port *iter; dev->parent = &parent_port->dev; port->depth = parent_port->depth + 1; port->parent_dport = parent_dport; /* * walk to the host bridge, or the first ancestor that knows * the host bridge */ iter = port; while (!iter->host_bridge && !is_cxl_root(to_cxl_port(iter->dev.parent))) iter = to_cxl_port(iter->dev.parent); if (iter->host_bridge) port->host_bridge = iter->host_bridge; else if (parent_dport->rch) port->host_bridge = parent_dport->dport_dev; else port->host_bridge = iter->uport_dev; dev_dbg(uport_dev, "host-bridge: %s\n", dev_name(port->host_bridge)); } else dev->parent = uport_dev; ida_init(&port->decoder_ida); port->hdm_end = -1; port->commit_end = -1; xa_init(&port->dports); xa_init(&port->endpoints); xa_init(&port->regions); device_initialize(dev); lockdep_set_class_and_subclass(&dev->mutex, &cxl_port_key, port->depth); device_set_pm_not_required(dev); dev->bus = &cxl_bus_type; dev->type = &cxl_port_type; return port; } static int cxl_setup_comp_regs(struct device *host, struct cxl_register_map *map, resource_size_t component_reg_phys) { *map = (struct cxl_register_map) { .host = host, .reg_type = CXL_REGLOC_RBI_EMPTY, .resource = component_reg_phys, }; if (component_reg_phys == CXL_RESOURCE_NONE) return 0; map->reg_type = CXL_REGLOC_RBI_COMPONENT; map->max_size = CXL_COMPONENT_REG_BLOCK_SIZE; return cxl_setup_regs(map); } static int cxl_port_setup_regs(struct cxl_port *port, resource_size_t component_reg_phys) { if (dev_is_platform(port->uport_dev)) return 0; return cxl_setup_comp_regs(&port->dev, &port->reg_map, component_reg_phys); } static int cxl_dport_setup_regs(struct device *host, struct cxl_dport *dport, resource_size_t component_reg_phys) { int rc; if (dev_is_platform(dport->dport_dev)) return 0; /* * use @dport->dport_dev for the context for error messages during * register probing, and fixup @host after the fact, since @host may be * NULL. */ rc = cxl_setup_comp_regs(dport->dport_dev, &dport->reg_map, component_reg_phys); dport->reg_map.host = host; return rc; } DEFINE_SHOW_ATTRIBUTE(einj_cxl_available_error_type); static int cxl_einj_inject(void *data, u64 type) { struct cxl_dport *dport = data; if (dport->rch) return einj_cxl_inject_rch_error(dport->rcrb.base, type); return einj_cxl_inject_error(to_pci_dev(dport->dport_dev), type); } DEFINE_DEBUGFS_ATTRIBUTE(cxl_einj_inject_fops, NULL, cxl_einj_inject, "0x%llx\n"); static void cxl_debugfs_create_dport_dir(struct cxl_dport *dport) { struct dentry *dir; if (!einj_cxl_is_initialized()) return; /* * dport_dev needs to be a PCIe port for CXL 2.0+ ports because * EINJ expects a dport SBDF to be specified for 2.0 error injection. */ if (!dport->rch && !dev_is_pci(dport->dport_dev)) return; dir = cxl_debugfs_create_dir(dev_name(dport->dport_dev)); debugfs_create_file("einj_inject", 0200, dir, dport, &cxl_einj_inject_fops); } static struct cxl_port *__devm_cxl_add_port(struct device *host, struct device *uport_dev, resource_size_t component_reg_phys, struct cxl_dport *parent_dport) { struct cxl_port *port; struct device *dev; int rc; port = cxl_port_alloc(uport_dev, parent_dport); if (IS_ERR(port)) return port; dev = &port->dev; if (is_cxl_memdev(uport_dev)) { struct cxl_memdev *cxlmd = to_cxl_memdev(uport_dev); struct cxl_dev_state *cxlds = cxlmd->cxlds; rc = dev_set_name(dev, "endpoint%d", port->id); if (rc) goto err; /* * The endpoint driver already enumerated the component and RAS * registers. Reuse that enumeration while prepping them to be * mapped by the cxl_port driver. */ port->reg_map = cxlds->reg_map; port->reg_map.host = &port->dev; cxlmd->endpoint = port; } else if (parent_dport) { rc = dev_set_name(dev, "port%d", port->id); if (rc) goto err; rc = cxl_port_setup_regs(port, component_reg_phys); if (rc) goto err; } else rc = dev_set_name(dev, "root%d", port->id); if (rc) goto err; rc = device_add(dev); if (rc) goto err; rc = devm_add_action_or_reset(host, unregister_port, port); if (rc) return ERR_PTR(rc); rc = devm_cxl_link_uport(host, port); if (rc) return ERR_PTR(rc); rc = devm_cxl_link_parent_dport(host, port, parent_dport); if (rc) return ERR_PTR(rc); if (parent_dport && dev_is_pci(uport_dev)) port->pci_latency = cxl_pci_get_latency(to_pci_dev(uport_dev)); return port; err: put_device(dev); return ERR_PTR(rc); } /** * devm_cxl_add_port - register a cxl_port in CXL memory decode hierarchy * @host: host device for devm operations * @uport_dev: "physical" device implementing this upstream port * @component_reg_phys: (optional) for configurable cxl_port instances * @parent_dport: next hop up in the CXL memory decode hierarchy */ struct cxl_port *devm_cxl_add_port(struct device *host, struct device *uport_dev, resource_size_t component_reg_phys, struct cxl_dport *parent_dport) { struct cxl_port *port, *parent_port; port = __devm_cxl_add_port(host, uport_dev, component_reg_phys, parent_dport); parent_port = parent_dport ? parent_dport->port : NULL; if (IS_ERR(port)) { dev_dbg(uport_dev, "Failed to add%s%s%s: %ld\n", parent_port ? " port to " : "", parent_port ? dev_name(&parent_port->dev) : "", parent_port ? "" : " root port", PTR_ERR(port)); } else { dev_dbg(uport_dev, "%s added%s%s%s\n", dev_name(&port->dev), parent_port ? " to " : "", parent_port ? dev_name(&parent_port->dev) : "", parent_port ? "" : " (root port)"); } return port; } EXPORT_SYMBOL_NS_GPL(devm_cxl_add_port, CXL); struct cxl_root *devm_cxl_add_root(struct device *host, const struct cxl_root_ops *ops) { struct cxl_root *cxl_root; struct cxl_port *port; port = devm_cxl_add_port(host, host, CXL_RESOURCE_NONE, NULL); if (IS_ERR(port)) return (struct cxl_root *)port; cxl_root = to_cxl_root(port); cxl_root->ops = ops; return cxl_root; } EXPORT_SYMBOL_NS_GPL(devm_cxl_add_root, CXL); struct pci_bus *cxl_port_to_pci_bus(struct cxl_port *port) { /* There is no pci_bus associated with a CXL platform-root port */ if (is_cxl_root(port)) return NULL; if (dev_is_pci(port->uport_dev)) { struct pci_dev *pdev = to_pci_dev(port->uport_dev); return pdev->subordinate; } return xa_load(&cxl_root_buses, (unsigned long)port->uport_dev); } EXPORT_SYMBOL_NS_GPL(cxl_port_to_pci_bus, CXL); static void unregister_pci_bus(void *uport_dev) { xa_erase(&cxl_root_buses, (unsigned long)uport_dev); } int devm_cxl_register_pci_bus(struct device *host, struct device *uport_dev, struct pci_bus *bus) { int rc; if (dev_is_pci(uport_dev)) return -EINVAL; rc = xa_insert(&cxl_root_buses, (unsigned long)uport_dev, bus, GFP_KERNEL); if (rc) return rc; return devm_add_action_or_reset(host, unregister_pci_bus, uport_dev); } EXPORT_SYMBOL_NS_GPL(devm_cxl_register_pci_bus, CXL); static bool dev_is_cxl_root_child(struct device *dev) { struct cxl_port *port, *parent; if (!is_cxl_port(dev)) return false; port = to_cxl_port(dev); if (is_cxl_root(port)) return false; parent = to_cxl_port(port->dev.parent); if (is_cxl_root(parent)) return true; return false; } struct cxl_root *find_cxl_root(struct cxl_port *port) { struct cxl_port *iter = port; while (iter && !is_cxl_root(iter)) iter = to_cxl_port(iter->dev.parent); if (!iter) return NULL; get_device(&iter->dev); return to_cxl_root(iter); } EXPORT_SYMBOL_NS_GPL(find_cxl_root, CXL); void put_cxl_root(struct cxl_root *cxl_root) { if (!cxl_root) return; put_device(&cxl_root->port.dev); } EXPORT_SYMBOL_NS_GPL(put_cxl_root, CXL); static struct cxl_dport *find_dport(struct cxl_port *port, int id) { struct cxl_dport *dport; unsigned long index; device_lock_assert(&port->dev); xa_for_each(&port->dports, index, dport) if (dport->port_id == id) return dport; return NULL; } static int add_dport(struct cxl_port *port, struct cxl_dport *dport) { struct cxl_dport *dup; int rc; device_lock_assert(&port->dev); dup = find_dport(port, dport->port_id); if (dup) { dev_err(&port->dev, "unable to add dport%d-%s non-unique port id (%s)\n", dport->port_id, dev_name(dport->dport_dev), dev_name(dup->dport_dev)); return -EBUSY; } rc = xa_insert(&port->dports, (unsigned long)dport->dport_dev, dport, GFP_KERNEL); if (rc) return rc; port->nr_dports++; return 0; } /* * Since root-level CXL dports cannot be enumerated by PCI they are not * enumerated by the common port driver that acquires the port lock over * dport add/remove. Instead, root dports are manually added by a * platform driver and cond_cxl_root_lock() is used to take the missing * port lock in that case. */ static void cond_cxl_root_lock(struct cxl_port *port) { if (is_cxl_root(port)) device_lock(&port->dev); } static void cond_cxl_root_unlock(struct cxl_port *port) { if (is_cxl_root(port)) device_unlock(&port->dev); } static void cxl_dport_remove(void *data) { struct cxl_dport *dport = data; struct cxl_port *port = dport->port; xa_erase(&port->dports, (unsigned long) dport->dport_dev); put_device(dport->dport_dev); } static void cxl_dport_unlink(void *data) { struct cxl_dport *dport = data; struct cxl_port *port = dport->port; char link_name[CXL_TARGET_STRLEN]; sprintf(link_name, "dport%d", dport->port_id); sysfs_remove_link(&port->dev.kobj, link_name); } static struct cxl_dport * __devm_cxl_add_dport(struct cxl_port *port, struct device *dport_dev, int port_id, resource_size_t component_reg_phys, resource_size_t rcrb) { char link_name[CXL_TARGET_STRLEN]; struct cxl_dport *dport; struct device *host; int rc; if (is_cxl_root(port)) host = port->uport_dev; else host = &port->dev; if (!host->driver) { dev_WARN_ONCE(&port->dev, 1, "dport:%s bad devm context\n", dev_name(dport_dev)); return ERR_PTR(-ENXIO); } if (snprintf(link_name, CXL_TARGET_STRLEN, "dport%d", port_id) >= CXL_TARGET_STRLEN) return ERR_PTR(-EINVAL); dport = devm_kzalloc(host, sizeof(*dport), GFP_KERNEL); if (!dport) return ERR_PTR(-ENOMEM); dport->dport_dev = dport_dev; dport->port_id = port_id; dport->port = port; if (rcrb == CXL_RESOURCE_NONE) { rc = cxl_dport_setup_regs(&port->dev, dport, component_reg_phys); if (rc) return ERR_PTR(rc); } else { dport->rcrb.base = rcrb; component_reg_phys = __rcrb_to_component(dport_dev, &dport->rcrb, CXL_RCRB_DOWNSTREAM); if (component_reg_phys == CXL_RESOURCE_NONE) { dev_warn(dport_dev, "Invalid Component Registers in RCRB"); return ERR_PTR(-ENXIO); } /* * RCH @dport is not ready to map until associated with its * memdev */ rc = cxl_dport_setup_regs(NULL, dport, component_reg_phys); if (rc) return ERR_PTR(rc); dport->rch = true; } if (component_reg_phys != CXL_RESOURCE_NONE) dev_dbg(dport_dev, "Component Registers found for dport: %pa\n", &component_reg_phys); cond_cxl_root_lock(port); rc = add_dport(port, dport); cond_cxl_root_unlock(port); if (rc) return ERR_PTR(rc); get_device(dport_dev); rc = devm_add_action_or_reset(host, cxl_dport_remove, dport); if (rc) return ERR_PTR(rc); rc = sysfs_create_link(&port->dev.kobj, &dport_dev->kobj, link_name); if (rc) return ERR_PTR(rc); rc = devm_add_action_or_reset(host, cxl_dport_unlink, dport); if (rc) return ERR_PTR(rc); if (dev_is_pci(dport_dev)) dport->link_latency = cxl_pci_get_latency(to_pci_dev(dport_dev)); cxl_debugfs_create_dport_dir(dport); return dport; } /** * devm_cxl_add_dport - append VH downstream port data to a cxl_port * @port: the cxl_port that references this dport * @dport_dev: firmware or PCI device representing the dport * @port_id: identifier for this dport in a decoder's target list * @component_reg_phys: optional location of CXL component registers * * Note that dports are appended to the devm release action's of the * either the port's host (for root ports), or the port itself (for * switch ports) */ struct cxl_dport *devm_cxl_add_dport(struct cxl_port *port, struct device *dport_dev, int port_id, resource_size_t component_reg_phys) { struct cxl_dport *dport; dport = __devm_cxl_add_dport(port, dport_dev, port_id, component_reg_phys, CXL_RESOURCE_NONE); if (IS_ERR(dport)) { dev_dbg(dport_dev, "failed to add dport to %s: %ld\n", dev_name(&port->dev), PTR_ERR(dport)); } else { dev_dbg(dport_dev, "dport added to %s\n", dev_name(&port->dev)); } return dport; } EXPORT_SYMBOL_NS_GPL(devm_cxl_add_dport, CXL); /** * devm_cxl_add_rch_dport - append RCH downstream port data to a cxl_port * @port: the cxl_port that references this dport * @dport_dev: firmware or PCI device representing the dport * @port_id: identifier for this dport in a decoder's target list * @rcrb: mandatory location of a Root Complex Register Block * * See CXL 3.0 9.11.8 CXL Devices Attached to an RCH */ struct cxl_dport *devm_cxl_add_rch_dport(struct cxl_port *port, struct device *dport_dev, int port_id, resource_size_t rcrb) { struct cxl_dport *dport; if (rcrb == CXL_RESOURCE_NONE) { dev_dbg(&port->dev, "failed to add RCH dport, missing RCRB\n"); return ERR_PTR(-EINVAL); } dport = __devm_cxl_add_dport(port, dport_dev, port_id, CXL_RESOURCE_NONE, rcrb); if (IS_ERR(dport)) { dev_dbg(dport_dev, "failed to add RCH dport to %s: %ld\n", dev_name(&port->dev), PTR_ERR(dport)); } else { dev_dbg(dport_dev, "RCH dport added to %s\n", dev_name(&port->dev)); } return dport; } EXPORT_SYMBOL_NS_GPL(devm_cxl_add_rch_dport, CXL); static int add_ep(struct cxl_ep *new) { struct cxl_port *port = new->dport->port; int rc; device_lock(&port->dev); if (port->dead) { device_unlock(&port->dev); return -ENXIO; } rc = xa_insert(&port->endpoints, (unsigned long)new->ep, new, GFP_KERNEL); device_unlock(&port->dev); return rc; } /** * cxl_add_ep - register an endpoint's interest in a port * @dport: the dport that routes to @ep_dev * @ep_dev: device representing the endpoint * * Intermediate CXL ports are scanned based on the arrival of endpoints. * When those endpoints depart the port can be destroyed once all * endpoints that care about that port have been removed. */ static int cxl_add_ep(struct cxl_dport *dport, struct device *ep_dev) { struct cxl_ep *ep; int rc; ep = kzalloc(sizeof(*ep), GFP_KERNEL); if (!ep) return -ENOMEM; ep->ep = get_device(ep_dev); ep->dport = dport; rc = add_ep(ep); if (rc) cxl_ep_release(ep); return rc; } struct cxl_find_port_ctx { const struct device *dport_dev; const struct cxl_port *parent_port; struct cxl_dport **dport; }; static int match_port_by_dport(struct device *dev, const void *data) { const struct cxl_find_port_ctx *ctx = data; struct cxl_dport *dport; struct cxl_port *port; if (!is_cxl_port(dev)) return 0; if (ctx->parent_port && dev->parent != &ctx->parent_port->dev) return 0; port = to_cxl_port(dev); dport = cxl_find_dport_by_dev(port, ctx->dport_dev); if (ctx->dport) *ctx->dport = dport; return dport != NULL; } static struct cxl_port *__find_cxl_port(struct cxl_find_port_ctx *ctx) { struct device *dev; if (!ctx->dport_dev) return NULL; dev = bus_find_device(&cxl_bus_type, NULL, ctx, match_port_by_dport); if (dev) return to_cxl_port(dev); return NULL; } static struct cxl_port *find_cxl_port(struct device *dport_dev, struct cxl_dport **dport) { struct cxl_find_port_ctx ctx = { .dport_dev = dport_dev, .dport = dport, }; struct cxl_port *port; port = __find_cxl_port(&ctx); return port; } static struct cxl_port *find_cxl_port_at(struct cxl_port *parent_port, struct device *dport_dev, struct cxl_dport **dport) { struct cxl_find_port_ctx ctx = { .dport_dev = dport_dev, .parent_port = parent_port, .dport = dport, }; struct cxl_port *port; port = __find_cxl_port(&ctx); return port; } /* * All users of grandparent() are using it to walk PCIe-like switch port * hierarchy. A PCIe switch is comprised of a bridge device representing the * upstream switch port and N bridges representing downstream switch ports. When * bridges stack the grand-parent of a downstream switch port is another * downstream switch port in the immediate ancestor switch. */ static struct device *grandparent(struct device *dev) { if (dev && dev->parent) return dev->parent->parent; return NULL; } static struct device *endpoint_host(struct cxl_port *endpoint) { struct cxl_port *port = to_cxl_port(endpoint->dev.parent); if (is_cxl_root(port)) return port->uport_dev; return &port->dev; } static void delete_endpoint(void *data) { struct cxl_memdev *cxlmd = data; struct cxl_port *endpoint = cxlmd->endpoint; struct device *host = endpoint_host(endpoint); device_lock(host); if (host->driver && !endpoint->dead) { devm_release_action(host, cxl_unlink_parent_dport, endpoint); devm_release_action(host, cxl_unlink_uport, endpoint); devm_release_action(host, unregister_port, endpoint); } cxlmd->endpoint = NULL; device_unlock(host); put_device(&endpoint->dev); put_device(host); } int cxl_endpoint_autoremove(struct cxl_memdev *cxlmd, struct cxl_port *endpoint) { struct device *host = endpoint_host(endpoint); struct device *dev = &cxlmd->dev; get_device(host); get_device(&endpoint->dev); cxlmd->depth = endpoint->depth; return devm_add_action_or_reset(dev, delete_endpoint, cxlmd); } EXPORT_SYMBOL_NS_GPL(cxl_endpoint_autoremove, CXL); /* * The natural end of life of a non-root 'cxl_port' is when its parent port goes * through a ->remove() event ("top-down" unregistration). The unnatural trigger * for a port to be unregistered is when all memdevs beneath that port have gone * through ->remove(). This "bottom-up" removal selectively removes individual * child ports manually. This depends on devm_cxl_add_port() to not change is * devm action registration order, and for dports to have already been * destroyed by reap_dports(). */ static void delete_switch_port(struct cxl_port *port) { devm_release_action(port->dev.parent, cxl_unlink_parent_dport, port); devm_release_action(port->dev.parent, cxl_unlink_uport, port); devm_release_action(port->dev.parent, unregister_port, port); } static void reap_dports(struct cxl_port *port) { struct cxl_dport *dport; unsigned long index; device_lock_assert(&port->dev); xa_for_each(&port->dports, index, dport) { devm_release_action(&port->dev, cxl_dport_unlink, dport); devm_release_action(&port->dev, cxl_dport_remove, dport); devm_kfree(&port->dev, dport); } } struct detach_ctx { struct cxl_memdev *cxlmd; int depth; }; static int port_has_memdev(struct device *dev, const void *data) { const struct detach_ctx *ctx = data; struct cxl_port *port; if (!is_cxl_port(dev)) return 0; port = to_cxl_port(dev); if (port->depth != ctx->depth) return 0; return !!cxl_ep_load(port, ctx->cxlmd); } static void cxl_detach_ep(void *data) { struct cxl_memdev *cxlmd = data; for (int i = cxlmd->depth - 1; i >= 1; i--) { struct cxl_port *port, *parent_port; struct detach_ctx ctx = { .cxlmd = cxlmd, .depth = i, }; struct device *dev; struct cxl_ep *ep; bool died = false; dev = bus_find_device(&cxl_bus_type, NULL, &ctx, port_has_memdev); if (!dev) continue; port = to_cxl_port(dev); parent_port = to_cxl_port(port->dev.parent); device_lock(&parent_port->dev); device_lock(&port->dev); ep = cxl_ep_load(port, cxlmd); dev_dbg(&cxlmd->dev, "disconnect %s from %s\n", ep ? dev_name(ep->ep) : "", dev_name(&port->dev)); cxl_ep_remove(port, ep); if (ep && !port->dead && xa_empty(&port->endpoints) && !is_cxl_root(parent_port) && parent_port->dev.driver) { /* * This was the last ep attached to a dynamically * enumerated port. Block new cxl_add_ep() and garbage * collect the port. */ died = true; port->dead = true; reap_dports(port); } device_unlock(&port->dev); if (died) { dev_dbg(&cxlmd->dev, "delete %s\n", dev_name(&port->dev)); delete_switch_port(port); } put_device(&port->dev); device_unlock(&parent_port->dev); } } static resource_size_t find_component_registers(struct device *dev) { struct cxl_register_map map; struct pci_dev *pdev; /* * Theoretically, CXL component registers can be hosted on a * non-PCI device, in practice, only cxl_test hits this case. */ if (!dev_is_pci(dev)) return CXL_RESOURCE_NONE; pdev = to_pci_dev(dev); cxl_find_regblock(pdev, CXL_REGLOC_RBI_COMPONENT, &map); return map.resource; } static int add_port_attach_ep(struct cxl_memdev *cxlmd, struct device *uport_dev, struct device *dport_dev) { struct device *dparent = grandparent(dport_dev); struct cxl_port *port, *parent_port = NULL; struct cxl_dport *dport, *parent_dport; resource_size_t component_reg_phys; int rc; if (!dparent) { /* * The iteration reached the topology root without finding the * CXL-root 'cxl_port' on a previous iteration, fail for now to * be re-probed after platform driver attaches. */ dev_dbg(&cxlmd->dev, "%s is a root dport\n", dev_name(dport_dev)); return -ENXIO; } parent_port = find_cxl_port(dparent, &parent_dport); if (!parent_port) { /* iterate to create this parent_port */ return -EAGAIN; } device_lock(&parent_port->dev); if (!parent_port->dev.driver) { dev_warn(&cxlmd->dev, "port %s:%s disabled, failed to enumerate CXL.mem\n", dev_name(&parent_port->dev), dev_name(uport_dev)); port = ERR_PTR(-ENXIO); goto out; } port = find_cxl_port_at(parent_port, dport_dev, &dport); if (!port) { component_reg_phys = find_component_registers(uport_dev); port = devm_cxl_add_port(&parent_port->dev, uport_dev, component_reg_phys, parent_dport); /* retry find to pick up the new dport information */ if (!IS_ERR(port)) port = find_cxl_port_at(parent_port, dport_dev, &dport); } out: device_unlock(&parent_port->dev); if (IS_ERR(port)) rc = PTR_ERR(port); else { dev_dbg(&cxlmd->dev, "add to new port %s:%s\n", dev_name(&port->dev), dev_name(port->uport_dev)); rc = cxl_add_ep(dport, &cxlmd->dev); if (rc == -EBUSY) { /* * "can't" happen, but this error code means * something to the caller, so translate it. */ rc = -ENXIO; } put_device(&port->dev); } put_device(&parent_port->dev); return rc; } int devm_cxl_enumerate_ports(struct cxl_memdev *cxlmd) { struct device *dev = &cxlmd->dev; struct device *iter; int rc; /* * Skip intermediate port enumeration in the RCH case, there * are no ports in between a host bridge and an endpoint. */ if (cxlmd->cxlds->rcd) return 0; rc = devm_add_action_or_reset(&cxlmd->dev, cxl_detach_ep, cxlmd); if (rc) return rc; /* * Scan for and add all cxl_ports in this device's ancestry. * Repeat until no more ports are added. Abort if a port add * attempt fails. */ retry: for (iter = dev; iter; iter = grandparent(iter)) { struct device *dport_dev = grandparent(iter); struct device *uport_dev; struct cxl_dport *dport; struct cxl_port *port; /* * The terminal "grandparent" in PCI is NULL and @platform_bus * for platform devices */ if (!dport_dev || dport_dev == &platform_bus) return 0; uport_dev = dport_dev->parent; if (!uport_dev) { dev_warn(dev, "at %s no parent for dport: %s\n", dev_name(iter), dev_name(dport_dev)); return -ENXIO; } dev_dbg(dev, "scan: iter: %s dport_dev: %s parent: %s\n", dev_name(iter), dev_name(dport_dev), dev_name(uport_dev)); port = find_cxl_port(dport_dev, &dport); if (port) { dev_dbg(&cxlmd->dev, "found already registered port %s:%s\n", dev_name(&port->dev), dev_name(port->uport_dev)); rc = cxl_add_ep(dport, &cxlmd->dev); /* * If the endpoint already exists in the port's list, * that's ok, it was added on a previous pass. * Otherwise, retry in add_port_attach_ep() after taking * the parent_port lock as the current port may be being * reaped. */ if (rc && rc != -EBUSY) { put_device(&port->dev); return rc; } /* Any more ports to add between this one and the root? */ if (!dev_is_cxl_root_child(&port->dev)) { put_device(&port->dev); continue; } put_device(&port->dev); return 0; } rc = add_port_attach_ep(cxlmd, uport_dev, dport_dev); /* port missing, try to add parent */ if (rc == -EAGAIN) continue; /* failed to add ep or port */ if (rc) return rc; /* port added, new descendants possible, start over */ goto retry; } return 0; } EXPORT_SYMBOL_NS_GPL(devm_cxl_enumerate_ports, CXL); struct cxl_port *cxl_pci_find_port(struct pci_dev *pdev, struct cxl_dport **dport) { return find_cxl_port(pdev->dev.parent, dport); } EXPORT_SYMBOL_NS_GPL(cxl_pci_find_port, CXL); struct cxl_port *cxl_mem_find_port(struct cxl_memdev *cxlmd, struct cxl_dport **dport) { return find_cxl_port(grandparent(&cxlmd->dev), dport); } EXPORT_SYMBOL_NS_GPL(cxl_mem_find_port, CXL); static int decoder_populate_targets(struct cxl_switch_decoder *cxlsd, struct cxl_port *port, int *target_map) { int i; if (!target_map) return 0; device_lock_assert(&port->dev); if (xa_empty(&port->dports)) return -EINVAL; guard(rwsem_write)(&cxl_region_rwsem); for (i = 0; i < cxlsd->cxld.interleave_ways; i++) { struct cxl_dport *dport = find_dport(port, target_map[i]); if (!dport) return -ENXIO; cxlsd->target[i] = dport; } return 0; } struct cxl_dport *cxl_hb_modulo(struct cxl_root_decoder *cxlrd, int pos) { struct cxl_switch_decoder *cxlsd = &cxlrd->cxlsd; struct cxl_decoder *cxld = &cxlsd->cxld; int iw; iw = cxld->interleave_ways; if (dev_WARN_ONCE(&cxld->dev, iw != cxlsd->nr_targets, "misconfigured root decoder\n")) return NULL; return cxlrd->cxlsd.target[pos % iw]; } EXPORT_SYMBOL_NS_GPL(cxl_hb_modulo, CXL); static struct lock_class_key cxl_decoder_key; /** * cxl_decoder_init - Common decoder setup / initialization * @port: owning port of this decoder * @cxld: common decoder properties to initialize * * A port may contain one or more decoders. Each of those decoders * enable some address space for CXL.mem utilization. A decoder is * expected to be configured by the caller before registering via * cxl_decoder_add() */ static int cxl_decoder_init(struct cxl_port *port, struct cxl_decoder *cxld) { struct device *dev; int rc; rc = ida_alloc(&port->decoder_ida, GFP_KERNEL); if (rc < 0) return rc; /* need parent to stick around to release the id */ get_device(&port->dev); cxld->id = rc; dev = &cxld->dev; device_initialize(dev); lockdep_set_class(&dev->mutex, &cxl_decoder_key); device_set_pm_not_required(dev); dev->parent = &port->dev; dev->bus = &cxl_bus_type; /* Pre initialize an "empty" decoder */ cxld->interleave_ways = 1; cxld->interleave_granularity = PAGE_SIZE; cxld->target_type = CXL_DECODER_HOSTONLYMEM; cxld->hpa_range = (struct range) { .start = 0, .end = -1, }; return 0; } static int cxl_switch_decoder_init(struct cxl_port *port, struct cxl_switch_decoder *cxlsd, int nr_targets) { if (nr_targets > CXL_DECODER_MAX_INTERLEAVE) return -EINVAL; cxlsd->nr_targets = nr_targets; return cxl_decoder_init(port, &cxlsd->cxld); } /** * cxl_root_decoder_alloc - Allocate a root level decoder * @port: owning CXL root of this decoder * @nr_targets: static number of downstream targets * @calc_hb: which host bridge covers the n'th position by granularity * * Return: A new cxl decoder to be registered by cxl_decoder_add(). A * 'CXL root' decoder is one that decodes from a top-level / static platform * firmware description of CXL resources into a CXL standard decode * topology. */ struct cxl_root_decoder *cxl_root_decoder_alloc(struct cxl_port *port, unsigned int nr_targets, cxl_calc_hb_fn calc_hb) { struct cxl_root_decoder *cxlrd; struct cxl_switch_decoder *cxlsd; struct cxl_decoder *cxld; int rc; if (!is_cxl_root(port)) return ERR_PTR(-EINVAL); cxlrd = kzalloc(struct_size(cxlrd, cxlsd.target, nr_targets), GFP_KERNEL); if (!cxlrd) return ERR_PTR(-ENOMEM); cxlsd = &cxlrd->cxlsd; rc = cxl_switch_decoder_init(port, cxlsd, nr_targets); if (rc) { kfree(cxlrd); return ERR_PTR(rc); } cxlrd->calc_hb = calc_hb; mutex_init(&cxlrd->range_lock); cxld = &cxlsd->cxld; cxld->dev.type = &cxl_decoder_root_type; /* * cxl_root_decoder_release() special cases negative ids to * detect memregion_alloc() failures. */ atomic_set(&cxlrd->region_id, -1); rc = memregion_alloc(GFP_KERNEL); if (rc < 0) { put_device(&cxld->dev); return ERR_PTR(rc); } atomic_set(&cxlrd->region_id, rc); cxlrd->qos_class = CXL_QOS_CLASS_INVALID; return cxlrd; } EXPORT_SYMBOL_NS_GPL(cxl_root_decoder_alloc, CXL); /** * cxl_switch_decoder_alloc - Allocate a switch level decoder * @port: owning CXL switch port of this decoder * @nr_targets: max number of dynamically addressable downstream targets * * Return: A new cxl decoder to be registered by cxl_decoder_add(). A * 'switch' decoder is any decoder that can be enumerated by PCIe * topology and the HDM Decoder Capability. This includes the decoders * that sit between Switch Upstream Ports / Switch Downstream Ports and * Host Bridges / Root Ports. */ struct cxl_switch_decoder *cxl_switch_decoder_alloc(struct cxl_port *port, unsigned int nr_targets) { struct cxl_switch_decoder *cxlsd; struct cxl_decoder *cxld; int rc; if (is_cxl_root(port) || is_cxl_endpoint(port)) return ERR_PTR(-EINVAL); cxlsd = kzalloc(struct_size(cxlsd, target, nr_targets), GFP_KERNEL); if (!cxlsd) return ERR_PTR(-ENOMEM); rc = cxl_switch_decoder_init(port, cxlsd, nr_targets); if (rc) { kfree(cxlsd); return ERR_PTR(rc); } cxld = &cxlsd->cxld; cxld->dev.type = &cxl_decoder_switch_type; return cxlsd; } EXPORT_SYMBOL_NS_GPL(cxl_switch_decoder_alloc, CXL); /** * cxl_endpoint_decoder_alloc - Allocate an endpoint decoder * @port: owning port of this decoder * * Return: A new cxl decoder to be registered by cxl_decoder_add() */ struct cxl_endpoint_decoder *cxl_endpoint_decoder_alloc(struct cxl_port *port) { struct cxl_endpoint_decoder *cxled; struct cxl_decoder *cxld; int rc; if (!is_cxl_endpoint(port)) return ERR_PTR(-EINVAL); cxled = kzalloc(sizeof(*cxled), GFP_KERNEL); if (!cxled) return ERR_PTR(-ENOMEM); cxled->pos = -1; cxld = &cxled->cxld; rc = cxl_decoder_init(port, cxld); if (rc) { kfree(cxled); return ERR_PTR(rc); } cxld->dev.type = &cxl_decoder_endpoint_type; return cxled; } EXPORT_SYMBOL_NS_GPL(cxl_endpoint_decoder_alloc, CXL); /** * cxl_decoder_add_locked - Add a decoder with targets * @cxld: The cxl decoder allocated by cxl__decoder_alloc() * @target_map: A list of downstream ports that this decoder can direct memory * traffic to. These numbers should correspond with the port number * in the PCIe Link Capabilities structure. * * Certain types of decoders may not have any targets. The main example of this * is an endpoint device. A more awkward example is a hostbridge whose root * ports get hot added (technically possible, though unlikely). * * This is the locked variant of cxl_decoder_add(). * * Context: Process context. Expects the device lock of the port that owns the * @cxld to be held. * * Return: Negative error code if the decoder wasn't properly configured; else * returns 0. */ int cxl_decoder_add_locked(struct cxl_decoder *cxld, int *target_map) { struct cxl_port *port; struct device *dev; int rc; if (WARN_ON_ONCE(!cxld)) return -EINVAL; if (WARN_ON_ONCE(IS_ERR(cxld))) return PTR_ERR(cxld); if (cxld->interleave_ways < 1) return -EINVAL; dev = &cxld->dev; port = to_cxl_port(cxld->dev.parent); if (!is_endpoint_decoder(dev)) { struct cxl_switch_decoder *cxlsd = to_cxl_switch_decoder(dev); rc = decoder_populate_targets(cxlsd, port, target_map); if (rc && (cxld->flags & CXL_DECODER_F_ENABLE)) { dev_err(&port->dev, "Failed to populate active decoder targets\n"); return rc; } } rc = dev_set_name(dev, "decoder%d.%d", port->id, cxld->id); if (rc) return rc; return device_add(dev); } EXPORT_SYMBOL_NS_GPL(cxl_decoder_add_locked, CXL); /** * cxl_decoder_add - Add a decoder with targets * @cxld: The cxl decoder allocated by cxl__decoder_alloc() * @target_map: A list of downstream ports that this decoder can direct memory * traffic to. These numbers should correspond with the port number * in the PCIe Link Capabilities structure. * * This is the unlocked variant of cxl_decoder_add_locked(). * See cxl_decoder_add_locked(). * * Context: Process context. Takes and releases the device lock of the port that * owns the @cxld. */ int cxl_decoder_add(struct cxl_decoder *cxld, int *target_map) { struct cxl_port *port; int rc; if (WARN_ON_ONCE(!cxld)) return -EINVAL; if (WARN_ON_ONCE(IS_ERR(cxld))) return PTR_ERR(cxld); port = to_cxl_port(cxld->dev.parent); device_lock(&port->dev); rc = cxl_decoder_add_locked(cxld, target_map); device_unlock(&port->dev); return rc; } EXPORT_SYMBOL_NS_GPL(cxl_decoder_add, CXL); static void cxld_unregister(void *dev) { struct cxl_endpoint_decoder *cxled; if (is_endpoint_decoder(dev)) { cxled = to_cxl_endpoint_decoder(dev); cxl_decoder_kill_region(cxled); } device_unregister(dev); } int cxl_decoder_autoremove(struct device *host, struct cxl_decoder *cxld) { return devm_add_action_or_reset(host, cxld_unregister, &cxld->dev); } EXPORT_SYMBOL_NS_GPL(cxl_decoder_autoremove, CXL); /** * __cxl_driver_register - register a driver for the cxl bus * @cxl_drv: cxl driver structure to attach * @owner: owning module/driver * @modname: KBUILD_MODNAME for parent driver */ int __cxl_driver_register(struct cxl_driver *cxl_drv, struct module *owner, const char *modname) { if (!cxl_drv->probe) { pr_debug("%s ->probe() must be specified\n", modname); return -EINVAL; } if (!cxl_drv->name) { pr_debug("%s ->name must be specified\n", modname); return -EINVAL; } if (!cxl_drv->id) { pr_debug("%s ->id must be specified\n", modname); return -EINVAL; } cxl_drv->drv.bus = &cxl_bus_type; cxl_drv->drv.owner = owner; cxl_drv->drv.mod_name = modname; cxl_drv->drv.name = cxl_drv->name; return driver_register(&cxl_drv->drv); } EXPORT_SYMBOL_NS_GPL(__cxl_driver_register, CXL); void cxl_driver_unregister(struct cxl_driver *cxl_drv) { driver_unregister(&cxl_drv->drv); } EXPORT_SYMBOL_NS_GPL(cxl_driver_unregister, CXL); static int cxl_bus_uevent(const struct device *dev, struct kobj_uevent_env *env) { return add_uevent_var(env, "MODALIAS=" CXL_MODALIAS_FMT, cxl_device_id(dev)); } static int cxl_bus_match(struct device *dev, struct device_driver *drv) { return cxl_device_id(dev) == to_cxl_drv(drv)->id; } static int cxl_bus_probe(struct device *dev) { int rc; rc = to_cxl_drv(dev->driver)->probe(dev); dev_dbg(dev, "probe: %d\n", rc); return rc; } static void cxl_bus_remove(struct device *dev) { struct cxl_driver *cxl_drv = to_cxl_drv(dev->driver); if (cxl_drv->remove) cxl_drv->remove(dev); } static struct workqueue_struct *cxl_bus_wq; static void cxl_bus_rescan_queue(struct work_struct *w) { int rc = bus_rescan_devices(&cxl_bus_type); pr_debug("CXL bus rescan result: %d\n", rc); } void cxl_bus_rescan(void) { static DECLARE_WORK(rescan_work, cxl_bus_rescan_queue); queue_work(cxl_bus_wq, &rescan_work); } EXPORT_SYMBOL_NS_GPL(cxl_bus_rescan, CXL); void cxl_bus_drain(void) { drain_workqueue(cxl_bus_wq); } EXPORT_SYMBOL_NS_GPL(cxl_bus_drain, CXL); bool schedule_cxl_memdev_detach(struct cxl_memdev *cxlmd) { return queue_work(cxl_bus_wq, &cxlmd->detach_work); } EXPORT_SYMBOL_NS_GPL(schedule_cxl_memdev_detach, CXL); static void add_latency(struct access_coordinate *c, long latency) { for (int i = 0; i < ACCESS_COORDINATE_MAX; i++) { c[i].write_latency += latency; c[i].read_latency += latency; } } static bool coordinates_valid(struct access_coordinate *c) { for (int i = 0; i < ACCESS_COORDINATE_MAX; i++) { if (c[i].read_bandwidth && c[i].write_bandwidth && c[i].read_latency && c[i].write_latency) continue; return false; } return true; } static void set_min_bandwidth(struct access_coordinate *c, unsigned int bw) { for (int i = 0; i < ACCESS_COORDINATE_MAX; i++) { c[i].write_bandwidth = min(c[i].write_bandwidth, bw); c[i].read_bandwidth = min(c[i].read_bandwidth, bw); } } static void set_access_coordinates(struct access_coordinate *out, struct access_coordinate *in) { for (int i = 0; i < ACCESS_COORDINATE_MAX; i++) out[i] = in[i]; } static bool parent_port_is_cxl_root(struct cxl_port *port) { return is_cxl_root(to_cxl_port(port->dev.parent)); } /** * cxl_endpoint_get_perf_coordinates - Retrieve performance numbers stored in dports * of CXL path * @port: endpoint cxl_port * @coord: output performance data * * Return: errno on failure, 0 on success. */ int cxl_endpoint_get_perf_coordinates(struct cxl_port *port, struct access_coordinate *coord) { struct cxl_memdev *cxlmd = to_cxl_memdev(port->uport_dev); struct access_coordinate c[] = { { .read_bandwidth = UINT_MAX, .write_bandwidth = UINT_MAX, }, { .read_bandwidth = UINT_MAX, .write_bandwidth = UINT_MAX, }, }; struct cxl_port *iter = port; struct cxl_dport *dport; struct pci_dev *pdev; struct device *dev; unsigned int bw; bool is_cxl_root; if (!is_cxl_endpoint(port)) return -EINVAL; /* * Skip calculation for RCD. Expectation is HMAT already covers RCD case * since RCH does not support hotplug. */ if (cxlmd->cxlds->rcd) return 0; /* * Exit the loop when the parent port of the current iter port is cxl * root. The iterative loop starts at the endpoint and gathers the * latency of the CXL link from the current device/port to the connected * downstream port each iteration. */ do { dport = iter->parent_dport; iter = to_cxl_port(iter->dev.parent); is_cxl_root = parent_port_is_cxl_root(iter); /* * There's no valid access_coordinate for a root port since RPs do not * have CDAT and therefore needs to be skipped. */ if (!is_cxl_root) { if (!coordinates_valid(dport->coord)) return -EINVAL; cxl_coordinates_combine(c, c, dport->coord); } add_latency(c, dport->link_latency); } while (!is_cxl_root); dport = iter->parent_dport; /* Retrieve HB coords */ if (!coordinates_valid(dport->coord)) return -EINVAL; cxl_coordinates_combine(c, c, dport->coord); dev = port->uport_dev->parent; if (!dev_is_pci(dev)) return -ENODEV; /* Get the calculated PCI paths bandwidth */ pdev = to_pci_dev(dev); bw = pcie_bandwidth_available(pdev, NULL, NULL, NULL); if (bw == 0) return -ENXIO; bw /= BITS_PER_BYTE; set_min_bandwidth(c, bw); set_access_coordinates(coord, c); return 0; } EXPORT_SYMBOL_NS_GPL(cxl_endpoint_get_perf_coordinates, CXL); /* for user tooling to ensure port disable work has completed */ static ssize_t flush_store(const struct bus_type *bus, const char *buf, size_t count) { if (sysfs_streq(buf, "1")) { flush_workqueue(cxl_bus_wq); return count; } return -EINVAL; } static BUS_ATTR_WO(flush); static struct attribute *cxl_bus_attributes[] = { &bus_attr_flush.attr, NULL, }; static struct attribute_group cxl_bus_attribute_group = { .attrs = cxl_bus_attributes, }; static const struct attribute_group *cxl_bus_attribute_groups[] = { &cxl_bus_attribute_group, NULL, }; struct bus_type cxl_bus_type = { .name = "cxl", .uevent = cxl_bus_uevent, .match = cxl_bus_match, .probe = cxl_bus_probe, .remove = cxl_bus_remove, .bus_groups = cxl_bus_attribute_groups, }; EXPORT_SYMBOL_NS_GPL(cxl_bus_type, CXL); static struct dentry *cxl_debugfs; struct dentry *cxl_debugfs_create_dir(const char *dir) { return debugfs_create_dir(dir, cxl_debugfs); } EXPORT_SYMBOL_NS_GPL(cxl_debugfs_create_dir, CXL); static __init int cxl_core_init(void) { int rc; cxl_debugfs = debugfs_create_dir("cxl", NULL); if (einj_cxl_is_initialized()) debugfs_create_file("einj_types", 0400, cxl_debugfs, NULL, &einj_cxl_available_error_type_fops); cxl_mbox_init(); rc = cxl_memdev_init(); if (rc) return rc; cxl_bus_wq = alloc_ordered_workqueue("cxl_port", 0); if (!cxl_bus_wq) { rc = -ENOMEM; goto err_wq; } rc = bus_register(&cxl_bus_type); if (rc) goto err_bus; rc = cxl_region_init(); if (rc) goto err_region; return 0; err_region: bus_unregister(&cxl_bus_type); err_bus: destroy_workqueue(cxl_bus_wq); err_wq: cxl_memdev_exit(); return rc; } static void cxl_core_exit(void) { cxl_region_exit(); bus_unregister(&cxl_bus_type); destroy_workqueue(cxl_bus_wq); cxl_memdev_exit(); debugfs_remove_recursive(cxl_debugfs); } subsys_initcall(cxl_core_init); module_exit(cxl_core_exit); MODULE_LICENSE("GPL v2"); MODULE_IMPORT_NS(CXL);