cxl/core/port: Rename bus.c to port.c
authorDan Williams <dan.j.williams@intel.com>
Mon, 24 Jan 2022 00:29:21 +0000 (16:29 -0800)
committerDan Williams <dan.j.williams@intel.com>
Wed, 9 Feb 2022 06:57:28 +0000 (22:57 -0800)
Given it is dominated by port infrastructure, and will only acquire
more, rename bus.c to port.c.

Reviewed-by: Ben Widawsky <ben.widawsky@intel.com>
Link: https://lore.kernel.org/r/164298416136.3018233.15442880970000855425.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Documentation/driver-api/cxl/memory-devices.rst
drivers/cxl/core/Makefile
drivers/cxl/core/bus.c [deleted file]
drivers/cxl/core/port.c [new file with mode: 0644]
tools/testing/cxl/Kbuild

index 3b8f413..c8f7a16 100644 (file)
@@ -36,10 +36,10 @@ CXL Core
 .. kernel-doc:: drivers/cxl/cxl.h
    :internal:
 
-.. kernel-doc:: drivers/cxl/core/bus.c
+.. kernel-doc:: drivers/cxl/core/port.c
    :doc: cxl core
 
-.. kernel-doc:: drivers/cxl/core/bus.c
+.. kernel-doc:: drivers/cxl/core/port.c
    :identifiers:
 
 .. kernel-doc:: drivers/cxl/core/pmem.c
index 40ab503..a90202a 100644 (file)
@@ -2,7 +2,7 @@
 obj-$(CONFIG_CXL_BUS) += cxl_core.o
 
 ccflags-y += -I$(srctree)/drivers/cxl
-cxl_core-y := bus.o
+cxl_core-y := port.o
 cxl_core-y += pmem.o
 cxl_core-y += regs.o
 cxl_core-y += memdev.o
diff --git a/drivers/cxl/core/bus.c b/drivers/cxl/core/bus.c
deleted file mode 100644 (file)
index 3f9b98e..0000000
+++ /dev/null
@@ -1,675 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/* Copyright(c) 2020 Intel Corporation. All rights reserved. */
-#include <linux/io-64-nonatomic-lo-hi.h>
-#include <linux/device.h>
-#include <linux/module.h>
-#include <linux/pci.h>
-#include <linux/slab.h>
-#include <linux/idr.h>
-#include <cxlmem.h>
-#include <cxl.h>
-#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);
-}
-
-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_NS_GPL(is_root_decoder, CXL);
-
-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_NS_GPL(to_cxl_decoder, CXL);
-
-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_NS_GPL(devm_cxl_add_port, CXL);
-
-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_NS_GPL(cxl_add_dport, CXL);
-
-static int decoder_populate_targets(struct cxl_decoder *cxld,
-                                   struct cxl_port *port, int *target_map)
-{
-       int rc = 0, i;
-
-       if (!target_map)
-               return 0;
-
-       device_lock(&port->dev);
-       if (list_empty(&port->dports)) {
-               rc = -EINVAL;
-               goto out_unlock;
-       }
-
-       for (i = 0; i < cxld->nr_targets; i++) {
-               struct cxl_dport *dport = find_dport(port, target_map[i]);
-
-               if (!dport) {
-                       rc = -ENXIO;
-                       goto out_unlock;
-               }
-               cxld->target[i] = dport;
-       }
-
-out_unlock:
-       device_unlock(&port->dev);
-
-       return rc;
-}
-
-struct cxl_decoder *cxl_decoder_alloc(struct cxl_port *port, int nr_targets)
-{
-       struct cxl_decoder *cxld;
-       struct device *dev;
-       int rc = 0;
-
-       if (nr_targets > CXL_DECODER_MAX_INTERLEAVE || nr_targets < 1)
-               return ERR_PTR(-EINVAL);
-
-       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;
-
-       cxld->id = rc;
-       cxld->nr_targets = nr_targets;
-       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);
-}
-EXPORT_SYMBOL_NS_GPL(cxl_decoder_alloc, CXL);
-
-int cxl_decoder_add(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;
-
-       port = to_cxl_port(cxld->dev.parent);
-       rc = decoder_populate_targets(cxld, port, target_map);
-       if (rc)
-               return rc;
-
-       dev = &cxld->dev;
-       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, CXL);
-
-static void cxld_unregister(void *dev)
-{
-       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_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_NS_GPL(cxl_bus_type, CXL);
-
-static __init int cxl_core_init(void)
-{
-       int rc;
-
-       cxl_mbox_init();
-
-       rc = cxl_memdev_init();
-       if (rc)
-               return rc;
-
-       rc = bus_register(&cxl_bus_type);
-       if (rc)
-               goto err;
-       return 0;
-
-err:
-       cxl_memdev_exit();
-       cxl_mbox_exit();
-       return rc;
-}
-
-static void cxl_core_exit(void)
-{
-       bus_unregister(&cxl_bus_type);
-       cxl_memdev_exit();
-       cxl_mbox_exit();
-}
-
-module_init(cxl_core_init);
-module_exit(cxl_core_exit);
-MODULE_LICENSE("GPL v2");
diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c
new file mode 100644 (file)
index 0000000..3f9b98e
--- /dev/null
@@ -0,0 +1,675 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright(c) 2020 Intel Corporation. All rights reserved. */
+#include <linux/io-64-nonatomic-lo-hi.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/slab.h>
+#include <linux/idr.h>
+#include <cxlmem.h>
+#include <cxl.h>
+#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);
+}
+
+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_NS_GPL(is_root_decoder, CXL);
+
+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_NS_GPL(to_cxl_decoder, CXL);
+
+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_NS_GPL(devm_cxl_add_port, CXL);
+
+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_NS_GPL(cxl_add_dport, CXL);
+
+static int decoder_populate_targets(struct cxl_decoder *cxld,
+                                   struct cxl_port *port, int *target_map)
+{
+       int rc = 0, i;
+
+       if (!target_map)
+               return 0;
+
+       device_lock(&port->dev);
+       if (list_empty(&port->dports)) {
+               rc = -EINVAL;
+               goto out_unlock;
+       }
+
+       for (i = 0; i < cxld->nr_targets; i++) {
+               struct cxl_dport *dport = find_dport(port, target_map[i]);
+
+               if (!dport) {
+                       rc = -ENXIO;
+                       goto out_unlock;
+               }
+               cxld->target[i] = dport;
+       }
+
+out_unlock:
+       device_unlock(&port->dev);
+
+       return rc;
+}
+
+struct cxl_decoder *cxl_decoder_alloc(struct cxl_port *port, int nr_targets)
+{
+       struct cxl_decoder *cxld;
+       struct device *dev;
+       int rc = 0;
+
+       if (nr_targets > CXL_DECODER_MAX_INTERLEAVE || nr_targets < 1)
+               return ERR_PTR(-EINVAL);
+
+       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;
+
+       cxld->id = rc;
+       cxld->nr_targets = nr_targets;
+       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);
+}
+EXPORT_SYMBOL_NS_GPL(cxl_decoder_alloc, CXL);
+
+int cxl_decoder_add(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;
+
+       port = to_cxl_port(cxld->dev.parent);
+       rc = decoder_populate_targets(cxld, port, target_map);
+       if (rc)
+               return rc;
+
+       dev = &cxld->dev;
+       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, CXL);
+
+static void cxld_unregister(void *dev)
+{
+       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_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_NS_GPL(cxl_bus_type, CXL);
+
+static __init int cxl_core_init(void)
+{
+       int rc;
+
+       cxl_mbox_init();
+
+       rc = cxl_memdev_init();
+       if (rc)
+               return rc;
+
+       rc = bus_register(&cxl_bus_type);
+       if (rc)
+               goto err;
+       return 0;
+
+err:
+       cxl_memdev_exit();
+       cxl_mbox_exit();
+       return rc;
+}
+
+static void cxl_core_exit(void)
+{
+       bus_unregister(&cxl_bus_type);
+       cxl_memdev_exit();
+       cxl_mbox_exit();
+}
+
+module_init(cxl_core_init);
+module_exit(cxl_core_exit);
+MODULE_LICENSE("GPL v2");
index 1acdf2f..3299fb0 100644 (file)
@@ -25,7 +25,7 @@ cxl_pmem-y += config_check.o
 
 obj-m += cxl_core.o
 
-cxl_core-y := $(CXL_CORE_SRC)/bus.o
+cxl_core-y := $(CXL_CORE_SRC)/port.o
 cxl_core-y += $(CXL_CORE_SRC)/pmem.o
 cxl_core-y += $(CXL_CORE_SRC)/regs.o
 cxl_core-y += $(CXL_CORE_SRC)/memdev.o