// SPDX-License-Identifier: GPL-2.0-only /* Copyright(c) 2020 Intel Corporation. All rights reserved. */ #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. */ static DEFINE_IDA(cxl_port_ida); 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 struct attribute *cxl_base_attributes[] = { &dev_attr_devtype.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->range.start); } static DEVICE_ATTR_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->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_ACCELERATOR: return sysfs_emit(buf, "accelerator\n"); case CXL_DECODER_EXPANDER: return sysfs_emit(buf, "expander\n"); } return -ENXIO; } static DEVICE_ATTR_RO(target_type); static ssize_t target_list_show(struct device *dev, struct device_attribute *attr, char *buf) { struct cxl_decoder *cxld = to_cxl_decoder(dev); ssize_t offset = 0; int i, rc = 0; device_lock(dev); for (i = 0; i < cxld->interleave_ways; i++) { struct cxl_dport *dport = cxld->target[i]; struct cxl_dport *next = NULL; if (!dport) break; if (i + 1 < cxld->interleave_ways) next = cxld->target[i + 1]; rc = sysfs_emit_at(buf, offset, "%d%s", dport->port_id, next ? "," : ""); if (rc < 0) break; offset += rc; } device_unlock(dev); if (rc < 0) return rc; rc = sysfs_emit_at(buf, offset, "\n"); if (rc < 0) return rc; return offset + rc; } static DEVICE_ATTR_RO(target_list); static struct attribute *cxl_decoder_base_attrs[] = { &dev_attr_start.attr, &dev_attr_size.attr, &dev_attr_locked.attr, &dev_attr_target_list.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, NULL, }; static struct attribute_group cxl_decoder_root_attribute_group = { .attrs = cxl_decoder_root_attrs, }; 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, 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 void cxl_decoder_release(struct device *dev) { struct cxl_decoder *cxld = to_cxl_decoder(dev); struct cxl_port *port = to_cxl_port(dev->parent); ida_free(&port->decoder_ida, cxld->id); kfree(cxld); put_device(&port->dev); } static const struct device_type cxl_decoder_switch_type = { .name = "cxl_decoder_switch", .release = cxl_decoder_release, .groups = cxl_decoder_switch_attribute_groups, }; static const struct device_type cxl_decoder_root_type = { .name = "cxl_decoder_root", .release = cxl_decoder_release, .groups = cxl_decoder_root_attribute_groups, }; bool is_root_decoder(struct device *dev) { return dev->type == &cxl_decoder_root_type; } EXPORT_SYMBOL_GPL(is_root_decoder); struct cxl_decoder *to_cxl_decoder(struct device *dev) { if (dev_WARN_ONCE(dev, dev->type->release != cxl_decoder_release, "not a cxl_decoder device\n")) return NULL; return container_of(dev, struct cxl_decoder, dev); } EXPORT_SYMBOL_GPL(to_cxl_decoder); static void cxl_dport_release(struct cxl_dport *dport) { list_del(&dport->list); put_device(dport->dport); kfree(dport); } static void cxl_port_release(struct device *dev) { struct cxl_port *port = to_cxl_port(dev); struct cxl_dport *dport, *_d; device_lock(dev); list_for_each_entry_safe(dport, _d, &port->dports, list) cxl_dport_release(dport); device_unlock(dev); ida_free(&cxl_port_ida, port->id); kfree(port); } static const struct attribute_group *cxl_port_attribute_groups[] = { &cxl_base_attribute_group, NULL, }; static const struct device_type cxl_port_type = { .name = "cxl_port", .release = cxl_port_release, .groups = cxl_port_attribute_groups, }; struct cxl_port *to_cxl_port(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); } static void unregister_port(void *_port) { struct cxl_port *port = _port; struct cxl_dport *dport; device_lock(&port->dev); list_for_each_entry(dport, &port->dports, list) { char link_name[CXL_TARGET_STRLEN]; if (snprintf(link_name, CXL_TARGET_STRLEN, "dport%d", dport->port_id) >= CXL_TARGET_STRLEN) continue; sysfs_remove_link(&port->dev.kobj, link_name); } device_unlock(&port->dev); 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->kobj, "uport"); if (rc) return rc; return devm_add_action_or_reset(host, cxl_unlink_uport, port); } static struct cxl_port *cxl_port_alloc(struct device *uport, resource_size_t component_reg_phys, struct cxl_port *parent_port) { struct cxl_port *port; struct device *dev; int rc; port = kzalloc(sizeof(*port), GFP_KERNEL); if (!port) return ERR_PTR(-ENOMEM); rc = ida_alloc(&cxl_port_ida, GFP_KERNEL); if (rc < 0) goto err; port->id = rc; /* * 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_port) dev->parent = &parent_port->dev; else dev->parent = uport; port->uport = uport; port->component_reg_phys = component_reg_phys; ida_init(&port->decoder_ida); INIT_LIST_HEAD(&port->dports); device_initialize(dev); device_set_pm_not_required(dev); dev->bus = &cxl_bus_type; dev->type = &cxl_port_type; return port; err: kfree(port); return ERR_PTR(rc); } /** * devm_cxl_add_port - register a cxl_port in CXL memory decode hierarchy * @host: host device for devm operations * @uport: "physical" device implementing this upstream port * @component_reg_phys: (optional) for configurable cxl_port instances * @parent_port: next hop up in the CXL memory decode hierarchy */ struct cxl_port *devm_cxl_add_port(struct device *host, struct device *uport, resource_size_t component_reg_phys, struct cxl_port *parent_port) { struct cxl_port *port; struct device *dev; int rc; port = cxl_port_alloc(uport, component_reg_phys, parent_port); if (IS_ERR(port)) return port; dev = &port->dev; if (parent_port) rc = dev_set_name(dev, "port%d", port->id); 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); return port; err: put_device(dev); return ERR_PTR(rc); } EXPORT_SYMBOL_GPL(devm_cxl_add_port); static struct cxl_dport *find_dport(struct cxl_port *port, int id) { struct cxl_dport *dport; device_lock_assert(&port->dev); list_for_each_entry (dport, &port->dports, list) if (dport->port_id == id) return dport; return NULL; } static int add_dport(struct cxl_port *port, struct cxl_dport *new) { struct cxl_dport *dup; device_lock(&port->dev); dup = find_dport(port, new->port_id); if (dup) dev_err(&port->dev, "unable to add dport%d-%s non-unique port id (%s)\n", new->port_id, dev_name(new->dport), dev_name(dup->dport)); else list_add_tail(&new->list, &port->dports); device_unlock(&port->dev); return dup ? -EEXIST : 0; } /** * cxl_add_dport - append 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 all allocations and links are undone by cxl_port deletion * and release. */ int cxl_add_dport(struct cxl_port *port, struct device *dport_dev, int port_id, resource_size_t component_reg_phys) { char link_name[CXL_TARGET_STRLEN]; struct cxl_dport *dport; int rc; if (snprintf(link_name, CXL_TARGET_STRLEN, "dport%d", port_id) >= CXL_TARGET_STRLEN) return -EINVAL; dport = kzalloc(sizeof(*dport), GFP_KERNEL); if (!dport) return -ENOMEM; INIT_LIST_HEAD(&dport->list); dport->dport = get_device(dport_dev); dport->port_id = port_id; dport->component_reg_phys = component_reg_phys; dport->port = port; rc = add_dport(port, dport); if (rc) goto err; rc = sysfs_create_link(&port->dev.kobj, &dport_dev->kobj, link_name); if (rc) goto err; return 0; err: cxl_dport_release(dport); return rc; } EXPORT_SYMBOL_GPL(cxl_add_dport); static struct cxl_decoder * cxl_decoder_alloc(struct cxl_port *port, int nr_targets, resource_size_t base, resource_size_t len, int interleave_ways, int interleave_granularity, enum cxl_decoder_type type, unsigned long flags) { struct cxl_decoder *cxld; struct device *dev; int rc = 0; if (interleave_ways < 1) return ERR_PTR(-EINVAL); device_lock(&port->dev); if (list_empty(&port->dports)) rc = -EINVAL; device_unlock(&port->dev); if (rc) return ERR_PTR(rc); cxld = kzalloc(struct_size(cxld, target, nr_targets), GFP_KERNEL); if (!cxld) return ERR_PTR(-ENOMEM); rc = ida_alloc(&port->decoder_ida, GFP_KERNEL); if (rc < 0) goto err; /* need parent to stick around to release the id */ get_device(&port->dev); *cxld = (struct cxl_decoder) { .id = rc, .range = { .start = base, .end = base + len - 1, }, .flags = flags, .interleave_ways = interleave_ways, .interleave_granularity = interleave_granularity, .target_type = type, }; /* handle implied target_list */ if (interleave_ways == 1) cxld->target[0] = list_first_entry(&port->dports, struct cxl_dport, list); dev = &cxld->dev; device_initialize(dev); device_set_pm_not_required(dev); dev->parent = &port->dev; dev->bus = &cxl_bus_type; /* root ports do not have a cxl_port_type parent */ if (port->dev.parent->type == &cxl_port_type) dev->type = &cxl_decoder_switch_type; else dev->type = &cxl_decoder_root_type; return cxld; err: kfree(cxld); return ERR_PTR(rc); } struct cxl_decoder * devm_cxl_add_decoder(struct device *host, struct cxl_port *port, int nr_targets, resource_size_t base, resource_size_t len, int interleave_ways, int interleave_granularity, enum cxl_decoder_type type, unsigned long flags) { struct cxl_decoder *cxld; struct device *dev; int rc; cxld = cxl_decoder_alloc(port, nr_targets, base, len, interleave_ways, interleave_granularity, type, flags); if (IS_ERR(cxld)) return cxld; dev = &cxld->dev; rc = dev_set_name(dev, "decoder%d.%d", port->id, cxld->id); if (rc) goto err; rc = device_add(dev); if (rc) goto err; rc = devm_add_action_or_reset(host, unregister_cxl_dev, dev); if (rc) return ERR_PTR(rc); return cxld; err: put_device(dev); return ERR_PTR(rc); } EXPORT_SYMBOL_GPL(devm_cxl_add_decoder); /** * __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_GPL(__cxl_driver_register); void cxl_driver_unregister(struct cxl_driver *cxl_drv) { driver_unregister(&cxl_drv->drv); } EXPORT_SYMBOL_GPL(cxl_driver_unregister); static int cxl_device_id(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; return 0; } static int cxl_bus_uevent(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) { return to_cxl_drv(dev->driver)->probe(dev); } 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); } struct bus_type cxl_bus_type = { .name = "cxl", .uevent = cxl_bus_uevent, .match = cxl_bus_match, .probe = cxl_bus_probe, .remove = cxl_bus_remove, }; EXPORT_SYMBOL_GPL(cxl_bus_type); static __init int cxl_core_init(void) { int rc; rc = cxl_memdev_init(); if (rc) return rc; rc = bus_register(&cxl_bus_type); if (rc) goto err; return 0; err: cxl_memdev_exit(); return rc; } static void cxl_core_exit(void) { bus_unregister(&cxl_bus_type); cxl_memdev_exit(); } module_init(cxl_core_init); module_exit(cxl_core_exit); MODULE_LICENSE("GPL v2");