summaryrefslogtreecommitdiffstats
path: root/drivers/cxl
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/cxl')
-rw-r--r--drivers/cxl/Kconfig5
-rw-r--r--drivers/cxl/Makefile2
-rw-r--r--drivers/cxl/acpi.c26
-rw-r--r--drivers/cxl/core/pci.c2
-rw-r--r--drivers/cxl/core/port.c34
-rw-r--r--drivers/cxl/cxl.h4
-rw-r--r--drivers/cxl/cxlpci.h1
-rw-r--r--drivers/cxl/port.c63
8 files changed, 108 insertions, 29 deletions
diff --git a/drivers/cxl/Kconfig b/drivers/cxl/Kconfig
index ef05e96f8f97..4f4f7587f6ca 100644
--- a/drivers/cxl/Kconfig
+++ b/drivers/cxl/Kconfig
@@ -77,4 +77,9 @@ config CXL_PMEM
provisioning the persistent memory capacity of CXL memory expanders.
If unsure say 'm'.
+
+config CXL_PORT
+ default CXL_BUS
+ tristate
+
endif
diff --git a/drivers/cxl/Makefile b/drivers/cxl/Makefile
index cf07ae6cea17..56fcac2323cb 100644
--- a/drivers/cxl/Makefile
+++ b/drivers/cxl/Makefile
@@ -3,7 +3,9 @@ obj-$(CONFIG_CXL_BUS) += core/
obj-$(CONFIG_CXL_PCI) += cxl_pci.o
obj-$(CONFIG_CXL_ACPI) += cxl_acpi.o
obj-$(CONFIG_CXL_PMEM) += cxl_pmem.o
+obj-$(CONFIG_CXL_PORT) += cxl_port.o
cxl_pci-y := pci.o
cxl_acpi-y := acpi.o
cxl_pmem-y := pmem.o
+cxl_port-y := port.o
diff --git a/drivers/cxl/acpi.c b/drivers/cxl/acpi.c
index 8c2ced91518b..82591642ea90 100644
--- a/drivers/cxl/acpi.c
+++ b/drivers/cxl/acpi.c
@@ -169,7 +169,6 @@ static int add_host_bridge_uport(struct device *match, void *arg)
struct acpi_device *bridge = to_cxl_host_bridge(host, match);
struct acpi_pci_root *pci_root;
struct cxl_dport *dport;
- struct cxl_hdm *cxlhdm;
struct cxl_port *port;
int rc;
@@ -197,28 +196,7 @@ static int add_host_bridge_uport(struct device *match, void *arg)
return PTR_ERR(port);
dev_dbg(host, "%s: add: %s\n", dev_name(match), dev_name(&port->dev));
- rc = devm_cxl_port_enumerate_dports(host, port);
- if (rc < 0)
- return rc;
- cxl_device_lock(&port->dev);
- if (rc == 1) {
- rc = devm_cxl_add_passthrough_decoder(host, port);
- goto out;
- }
-
- cxlhdm = devm_cxl_setup_hdm(host, port);
- if (IS_ERR(cxlhdm)) {
- rc = PTR_ERR(cxlhdm);
- goto out;
- }
-
- rc = devm_cxl_enumerate_decoders(host, cxlhdm);
- if (rc)
- dev_err(&port->dev, "Couldn't enumerate decoders (%d)\n", rc);
-
-out:
- cxl_device_unlock(&port->dev);
- return rc;
+ return 0;
}
struct cxl_chbs_context {
@@ -278,9 +256,7 @@ static int add_host_bridge_dport(struct device *match, void *arg)
return 0;
}
- cxl_device_lock(&root_port->dev);
dport = devm_cxl_add_dport(host, root_port, match, uid, ctx.chbcr);
- cxl_device_unlock(&root_port->dev);
if (IS_ERR(dport)) {
dev_err(host, "failed to add downstream port: %s\n",
dev_name(match));
diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
index c5a9e03ed477..8ec5f74da679 100644
--- a/drivers/cxl/core/pci.c
+++ b/drivers/cxl/core/pci.c
@@ -47,10 +47,8 @@ static int match_add_dports(struct pci_dev *pdev, void *data)
dev_dbg(&port->dev, "failed to find component registers\n");
port_num = FIELD_GET(PCI_EXP_LNKCAP_PN, lnkcap);
- cxl_device_lock(&port->dev);
dport = devm_cxl_add_dport(ctx->host, port, &pdev->dev, port_num,
cxl_regmap_to_base(pdev, &map));
- cxl_device_unlock(&port->dev);
if (IS_ERR(dport)) {
ctx->error = PTR_ERR(dport);
return PTR_ERR(dport);
diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c
index 0bbd8fb8f35d..a66284b7eb1b 100644
--- a/drivers/cxl/core/port.c
+++ b/drivers/cxl/core/port.c
@@ -40,6 +40,11 @@ static int cxl_device_id(struct device *dev)
return CXL_DEVICE_NVDIMM_BRIDGE;
if (dev->type == &cxl_nvdimm_type)
return CXL_DEVICE_NVDIMM;
+ if (is_cxl_port(dev)) {
+ if (is_cxl_root(to_cxl_port(dev)))
+ return CXL_DEVICE_ROOT;
+ return CXL_DEVICE_PORT;
+ }
return 0;
}
@@ -298,6 +303,9 @@ static void unregister_port(void *_port)
{
struct cxl_port *port = _port;
+ if (!is_cxl_root(port))
+ device_lock_assert(port->dev.parent);
+
device_unregister(&port->dev);
}
@@ -526,15 +534,34 @@ static int add_dport(struct cxl_port *port, struct cxl_dport *new)
return dup ? -EEXIST : 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))
+ cxl_device_lock(&port->dev);
+}
+
+static void cond_cxl_root_unlock(struct cxl_port *port)
+{
+ if (is_cxl_root(port))
+ cxl_device_unlock(&port->dev);
+}
+
static void cxl_dport_remove(void *data)
{
struct cxl_dport *dport = data;
struct cxl_port *port = dport->port;
put_device(dport->dport);
- cxl_device_lock(&port->dev);
+ cond_cxl_root_lock(port);
list_del(&dport->list);
- cxl_device_unlock(&port->dev);
+ cond_cxl_root_unlock(port);
}
static void cxl_dport_unlink(void *data)
@@ -587,7 +614,9 @@ struct cxl_dport *devm_cxl_add_dport(struct device *host, struct cxl_port *port,
dport->component_reg_phys = component_reg_phys;
dport->port = port;
+ cond_cxl_root_lock(port);
rc = add_dport(port, dport);
+ cond_cxl_root_unlock(port);
if (rc)
return ERR_PTR(rc);
@@ -895,6 +924,7 @@ static int cxl_bus_probe(struct device *dev)
rc = to_cxl_drv(dev->driver)->probe(dev);
cxl_nested_unlock(dev);
+ dev_dbg(dev, "probe: %d\n", rc);
return rc;
}
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index c127d5c0ac96..2b24eb56618f 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -163,6 +163,8 @@ int cxl_map_device_regs(struct pci_dev *pdev,
enum cxl_regloc_type;
int cxl_find_regblock(struct pci_dev *pdev, enum cxl_regloc_type type,
struct cxl_register_map *map);
+void __iomem *devm_cxl_iomap_block(struct device *dev, resource_size_t addr,
+ resource_size_t length);
#define CXL_RESOURCE_NONE ((resource_size_t) -1)
#define CXL_TARGET_STRLEN 20
@@ -354,6 +356,8 @@ void cxl_driver_unregister(struct cxl_driver *cxl_drv);
#define CXL_DEVICE_NVDIMM_BRIDGE 1
#define CXL_DEVICE_NVDIMM 2
+#define CXL_DEVICE_PORT 3
+#define CXL_DEVICE_ROOT 4
#define MODULE_ALIAS_CXL(type) MODULE_ALIAS("cxl:t" __stringify(type) "*")
#define CXL_MODALIAS_FMT "cxl:t%d"
diff --git a/drivers/cxl/cxlpci.h b/drivers/cxl/cxlpci.h
index 103636fda198..47640f19e899 100644
--- a/drivers/cxl/cxlpci.h
+++ b/drivers/cxl/cxlpci.h
@@ -2,6 +2,7 @@
/* Copyright(c) 2020 Intel Corporation. All rights reserved. */
#ifndef __CXL_PCI_H__
#define __CXL_PCI_H__
+#include <linux/pci.h>
#include "cxl.h"
#define CXL_MEMORY_PROGIF 0x10
diff --git a/drivers/cxl/port.c b/drivers/cxl/port.c
new file mode 100644
index 000000000000..daa4c3c33aed
--- /dev/null
+++ b/drivers/cxl/port.c
@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright(c) 2022 Intel Corporation. All rights reserved. */
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+#include "cxlmem.h"
+#include "cxlpci.h"
+
+/**
+ * DOC: cxl port
+ *
+ * The port driver enumerates dport via PCI and scans for HDM
+ * (Host-managed-Device-Memory) decoder resources via the
+ * @component_reg_phys value passed in by the agent that registered the
+ * port. All descendant ports of a CXL root port (described by platform
+ * firmware) are managed in this drivers context. Each driver instance
+ * is responsible for tearing down the driver context of immediate
+ * descendant ports. The locking for this is validated by
+ * CONFIG_PROVE_CXL_LOCKING.
+ *
+ * The primary service this driver provides is presenting APIs to other
+ * drivers to utilize the decoders, and indicating to userspace (via bind
+ * status) the connectivity of the CXL.mem protocol throughout the
+ * PCIe topology.
+ */
+
+static int cxl_port_probe(struct device *dev)
+{
+ struct cxl_port *port = to_cxl_port(dev);
+ struct cxl_hdm *cxlhdm;
+ int rc;
+
+ rc = devm_cxl_port_enumerate_dports(dev, port);
+ if (rc < 0)
+ return rc;
+
+ if (rc == 1)
+ return devm_cxl_add_passthrough_decoder(dev, port);
+
+ cxlhdm = devm_cxl_setup_hdm(dev, port);
+ if (IS_ERR(cxlhdm))
+ return PTR_ERR(cxlhdm);
+
+ rc = devm_cxl_enumerate_decoders(dev, cxlhdm);
+ if (rc) {
+ dev_err(dev, "Couldn't enumerate decoders (%d)\n", rc);
+ return rc;
+ }
+
+ return 0;
+}
+
+static struct cxl_driver cxl_port_driver = {
+ .name = "cxl_port",
+ .probe = cxl_port_probe,
+ .id = CXL_DEVICE_PORT,
+};
+
+module_cxl_driver(cxl_port_driver);
+MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(CXL);
+MODULE_ALIAS_CXL(CXL_DEVICE_PORT);