WSL2-Linux-Kernel/drivers/cxl/core/port.c

1998 строки
49 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/* Copyright(c) 2020 Intel Corporation. All rights reserved. */
#include <linux/memregion.h>
#include <linux/workqueue.h>
#include <linux/debugfs.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 <cxlpci.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 DEFINE_XARRAY(cxl_root_buses);
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;
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_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 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;
unsigned int seq;
int rc;
do {
seq = read_seqbegin(&cxlsd->target_lock);
rc = emit_target_list(cxlsd, buf);
} while (read_seqretry(&cxlsd->target_lock, seq));
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);
u64 base = cxl_dpa_resource_start(cxled);
return sysfs_emit(buf, "%#llx\n", base);
}
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 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,
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);
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,
};
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;
else if (is_cxl_root(parent))
lock_dev = parent->uport;
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->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->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,
resource_size_t component_reg_phys,
struct cxl_dport *parent_dport)
{
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;
port->uport = uport;
/*
* 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;
else
port->host_bridge = iter->uport;
dev_dbg(uport, "host-bridge: %s\n", dev_name(port->host_bridge));
} else
dev->parent = uport;
port->component_reg_phys = component_reg_phys;
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;
err:
kfree(port);
return ERR_PTR(rc);
}
static struct cxl_port *__devm_cxl_add_port(struct device *host,
struct device *uport,
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, component_reg_phys, parent_dport);
if (IS_ERR(port))
return port;
dev = &port->dev;
if (is_cxl_memdev(uport))
rc = dev_set_name(dev, "endpoint%d", port->id);
else if (parent_dport)
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);
rc = devm_cxl_link_parent_dport(host, port, parent_dport);
if (rc)
return ERR_PTR(rc);
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: "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,
resource_size_t component_reg_phys,
struct cxl_dport *parent_dport)
{
struct cxl_port *port, *parent_port;
port = __devm_cxl_add_port(host, uport, component_reg_phys,
parent_dport);
parent_port = parent_dport ? parent_dport->port : NULL;
if (IS_ERR(port)) {
dev_dbg(uport, "Failed to add %s%s%s%s: %ld\n",
dev_name(&port->dev),
parent_port ? " to " : "",
parent_port ? dev_name(&parent_port->dev) : "",
parent_port ? "" : " (root port)",
PTR_ERR(port));
} else {
dev_dbg(uport, "%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 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)) {
struct pci_dev *pdev = to_pci_dev(port->uport);
return pdev->subordinate;
}
return xa_load(&cxl_root_buses, (unsigned long)port->uport);
}
EXPORT_SYMBOL_NS_GPL(cxl_port_to_pci_bus, CXL);
static void unregister_pci_bus(void *uport)
{
xa_erase(&cxl_root_buses, (unsigned long)uport);
}
int devm_cxl_register_pci_bus(struct device *host, struct device *uport,
struct pci_bus *bus)
{
int rc;
if (dev_is_pci(uport))
return -EINVAL;
rc = xa_insert(&cxl_root_buses, (unsigned long)uport, bus, GFP_KERNEL);
if (rc)
return rc;
return devm_add_action_or_reset(host, unregister_pci_bus, uport);
}
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_port *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 iter;
}
EXPORT_SYMBOL_NS_GPL(find_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 *new)
{
struct cxl_dport *dup;
int rc;
device_lock_assert(&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));
return -EBUSY;
}
rc = xa_insert(&port->dports, (unsigned long)new->dport, new,
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);
put_device(dport->dport);
}
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;
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 = dport_dev;
dport->port_id = port_id;
dport->component_reg_phys = component_reg_phys;
dport->port = port;
if (rcrb != CXL_RESOURCE_NONE)
dport->rch = true;
dport->rcrb = rcrb;
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);
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
* @component_reg_phys: optional location of CXL component registers
* @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 component_reg_phys,
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,
component_reg_phys, 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 void delete_endpoint(void *data)
{
struct cxl_memdev *cxlmd = data;
struct cxl_port *endpoint = dev_get_drvdata(&cxlmd->dev);
struct cxl_port *parent_port;
struct device *parent;
parent_port = cxl_mem_find_port(cxlmd, NULL);
if (!parent_port)
goto out;
parent = &parent_port->dev;
device_lock(parent);
if (parent->driver && !endpoint->dead) {
devm_release_action(parent, cxl_unlink_parent_dport, endpoint);
devm_release_action(parent, cxl_unlink_uport, endpoint);
devm_release_action(parent, unregister_port, endpoint);
}
device_unlock(parent);
put_device(parent);
out:
put_device(&endpoint->dev);
}
int cxl_endpoint_autoremove(struct cxl_memdev *cxlmd, struct cxl_port *endpoint)
{
struct device *dev = &cxlmd->dev;
get_device(&endpoint->dev);
dev_set_drvdata(dev, endpoint);
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));
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;
if (!dport_dev)
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));
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_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, rc = 0;
if (!target_map)
return 0;
device_lock_assert(&port->dev);
if (xa_empty(&port->dports))
return -EINVAL;
write_seqlock(&cxlsd->target_lock);
for (i = 0; i < cxlsd->nr_targets; i++) {
struct cxl_dport *dport = find_dport(port, target_map[i]);
if (!dport) {
rc = -ENXIO;
break;
}
cxlsd->target[i] = dport;
}
write_sequnlock(&cxlsd->target_lock);
return rc;
}
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_EXPANDER;
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;
seqlock_init(&cxlsd->target_lock);
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);
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_<type>_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_<type>_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);
/* 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);
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");