[RFC,v4,2/8] bus/cdx: add the cdx bus driver

diff --git a/MAINTAINERS b/MAINTAINERS
index 5f48f11fe0c3..6b7b3c098839 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -940,6 +940,8 @@  M:	Nipun Gupta <nipun.gupta@amd.com>
 M:	Nikhil Agarwal <nikhil.agarwal@amd.com>
 S:	Maintained
 F:	Documentation/devicetree/bindings/bus/xlnx,cdx.yaml
+F:	drivers/bus/cdx/*
+F:	include/linux/cdx/*
 
 AMD CRYPTOGRAPHIC COPROCESSOR (CCP) DRIVER - SEV SUPPORT
 M:	Brijesh Singh <brijesh.singh@amd.com>
diff --git a/drivers/bus/Kconfig b/drivers/bus/Kconfig
index 7bfe998f3514..b0324efb9a6a 100644
--- a/drivers/bus/Kconfig
+++ b/drivers/bus/Kconfig
@@ -251,5 +251,6 @@  config DA8XX_MSTPRI
 
 source "drivers/bus/fsl-mc/Kconfig"
 source "drivers/bus/mhi/Kconfig"
+source "drivers/bus/cdx/Kconfig"
 
 endmenu
diff --git a/drivers/bus/Makefile b/drivers/bus/Makefile
index d90eed189a65..88649111c395 100644
--- a/drivers/bus/Makefile
+++ b/drivers/bus/Makefile
@@ -20,6 +20,9 @@  obj-$(CONFIG_INTEL_IXP4XX_EB)	+= intel-ixp4xx-eb.o
 obj-$(CONFIG_MIPS_CDMM)		+= mips_cdmm.o
 obj-$(CONFIG_MVEBU_MBUS) 	+= mvebu-mbus.o
 
+#CDX bus
+obj-$(CONFIG_CDX_BUS)		+= cdx/
+
 # Interconnect bus driver for OMAP SoCs.
 obj-$(CONFIG_OMAP_INTERCONNECT)	+= omap_l3_smx.o omap_l3_noc.o
 
diff --git a/drivers/bus/cdx/Kconfig b/drivers/bus/cdx/Kconfig
new file mode 100644
index 000000000000..98ec05ad708d
--- /dev/null
+++ b/drivers/bus/cdx/Kconfig
@@ -0,0 +1,13 @@ 
+# SPDX-License-Identifier: GPL-2.0
+#
+# CDX bus configuration
+#
+# Copyright (C) 2022, Advanced Micro Devices, Inc.
+#
+
+config CDX_BUS
+	bool "CDX Bus driver"
+	help
+		Driver to enable CDX Bus infrastructure. CDX bus uses
+		CDX controller and firmware to scan the FPGA based
+		devices.
diff --git a/drivers/bus/cdx/Makefile b/drivers/bus/cdx/Makefile
new file mode 100644
index 000000000000..2e8f42611dfc
--- /dev/null
+++ b/drivers/bus/cdx/Makefile
@@ -0,0 +1,8 @@ 
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for CDX
+#
+# Copyright (C) 2022, Advanced Micro Devices, Inc.
+#
+
+obj-$(CONFIG_CDX_BUS) += cdx.o
diff --git a/drivers/bus/cdx/cdx.c b/drivers/bus/cdx/cdx.c
new file mode 100644
index 000000000000..5a366f4ae69c
--- /dev/null
+++ b/drivers/bus/cdx/cdx.c
@@ -0,0 +1,366 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * CDX bus driver.
+ *
+ * Copyright (C) 2022, Advanced Micro Devices, Inc.
+ */
+
+/*
+ * Architecture Overview
+ * =====================
+ * CDX is a Hardware Architecture designed for AMD FPGA devices. It
+ * consists of sophisticated mechanism for interaction between FPGA,
+ * Firmware and the APUs (Application CPUs).
+ *
+ * Firmware resides on RPU (Realtime CPUs) which interacts with
+ * the FPGA program manager and the APUs. The RPU provides memory-mapped
+ * interface (RPU if) which is used to communicate with APUs.
+ *
+ * The diagram below shows an overview of the CDX architecture:
+ *
+ *          +--------------------------------------+
+ *          |    Application CPUs (APU)            |
+ *          |                                      |
+ *          |                    CDX device drivers|
+ *          |     Linux OS                |        |
+ *          |                        CDX bus       |
+ *          |                             |        |
+ *          |                     CDX controller   |
+ *          |                             |        |
+ *          +-----------------------------|--------+
+ *                                        | (discover, config,
+ *                                        |  reset, rescan)
+ *                                        |
+ *          +------------------------| RPU if |----+
+ *          |                             |        |
+ *          |                             V        |
+ *          |          Realtime CPUs (RPU)         |
+ *          |                                      |
+ *          +--------------------------------------+
+ *                                |
+ *          +---------------------|----------------+
+ *          |  FPGA               |                |
+ *          |      +-----------------------+       |
+ *          |      |           |           |       |
+ *          | +-------+    +-------+   +-------+   |
+ *          | | dev 1 |    | dev 2 |   | dev 3 |   |
+ *          | +-------+    +-------+   +-------+   |
+ *          +--------------------------------------+
+ *
+ * The RPU firmware extracts the device information from the loaded FPGA
+ * image and implements a mechanism that allows the APU drivers to
+ * enumerate such devices (device personality and resource details) via
+ * a dedicated communication channel. RPU mediates operations such as
+ * discover, reset and rescan of the FPGA devices for the APU. This is
+ * done using memory mapped interface provided by the RPU to APU.
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/cdx/cdx_bus.h>
+
+#include "cdx.h"
+
+/*
+ * Default DMA mask for devices on a CDX bus
+ */
+#define CDX_DEFAULT_DMA_MASK	(~0ULL)
+
+static struct cdx_controller_t *cdx_controller;
+
+static int reset_cdx_device(struct device *dev, void * __always_unused data)
+{
+	struct cdx_device *cdx_dev = to_cdx_device(dev);
+	struct cdx_controller_t *cdx = cdx_dev->cdx;
+	int ret;
+
+	ret = cdx->ops.reset_dev(cdx, cdx_dev->bus_num, cdx_dev->dev_num);
+	if (ret)
+		dev_err(dev, "cdx device reset failed\n");
+
+	return ret;
+}
+
+int cdx_dev_reset(struct device *dev)
+{
+	return reset_cdx_device(dev, NULL);
+}
+EXPORT_SYMBOL_GPL(cdx_dev_reset);
+
+static int cdx_unregister_device(struct device *dev,
+				 void * __always_unused data)
+{
+	struct cdx_device *cdx_dev = to_cdx_device(dev);
+
+	kfree(cdx_dev->driver_override);
+	cdx_dev->driver_override = NULL;
+
+	/*
+	 * Do not free cdx_dev here as it would be freed in
+	 * cdx_device_release() called from within put_device().
+	 */
+	device_del(&cdx_dev->dev);
+	put_device(&cdx_dev->dev);
+
+	return 0;
+}
+
+/**
+ * cdx_match_one_device - Tell if a CDX device structure has a matching
+ *			  CDX device id structure
+ * @id: single CDX device id structure to match
+ * @dev: the CDX device structure to match against
+ *
+ * Returns the matching cdx_device_id structure or NULL if there is no match.
+ */
+static inline const struct cdx_device_id *
+cdx_match_one_device(const struct cdx_device_id *id,
+		     const struct cdx_device *dev)
+{
+	/* Use vendor ID and device ID for matching */
+	if ((id->vendor == dev->vendor) && (id->device == dev->device))
+		return id;
+	return NULL;
+}
+
+/**
+ * cdx_match_id - See if a CDX device matches a given cdx_id table
+ * @ids: array of CDX device ID structures to search in
+ * @dev: the CDX device structure to match against.
+ *
+ * Used by a driver to check whether a CDX device is in its list of
+ * supported devices.  Returns the matching cdx_device_id structure or
+ * NULL if there is no match.
+ */
+static inline const struct cdx_device_id *
+cdx_match_id(const struct cdx_device_id *ids, struct cdx_device *dev)
+{
+	if (ids) {
+		while (ids->vendor || ids->device) {
+			if (cdx_match_one_device(ids, dev))
+				return ids;
+			ids++;
+		}
+	}
+	return NULL;
+}
+
+/**
+ * cdx_bus_match - device to driver matching callback
+ * @dev: the cdx device to match against
+ * @drv: the device driver to search for matching cdx device
+ * structures
+ *
+ * Returns 1 on success, 0 otherwise.
+ */
+static int cdx_bus_match(struct device *dev, struct device_driver *drv)
+{
+	struct cdx_device *cdx_dev = to_cdx_device(dev);
+	struct cdx_driver *cdx_drv = to_cdx_driver(drv);
+	const struct cdx_device_id *found_id;
+
+	/* When driver_override is set, only bind to the matching driver */
+	if (cdx_dev->driver_override)
+		return !strcmp(cdx_dev->driver_override, cdx_drv->driver.name);
+
+	found_id = cdx_match_id(cdx_drv->match_id_table, cdx_dev);
+	if (found_id)
+		return true;
+
+	return false;
+}
+
+static void cdx_remove(struct device *dev)
+{
+	struct cdx_driver *cdx_drv = to_cdx_driver(dev->driver);
+	struct cdx_device *cdx_dev = to_cdx_device(dev);
+
+	if (cdx_drv->remove)
+		cdx_drv->remove(cdx_dev);
+}
+
+struct bus_type cdx_bus_type = {
+	.name		= "cdx",
+	.match		= cdx_bus_match,
+	.remove		= cdx_remove,
+};
+EXPORT_SYMBOL_GPL(cdx_bus_type);
+
+static int cdx_driver_probe(struct device *dev)
+{
+	struct cdx_driver *cdx_drv = to_cdx_driver(dev->driver);
+	struct cdx_device *cdx_dev = to_cdx_device(dev);
+	int error;
+
+	error = cdx_drv->probe(cdx_dev);
+	if (error < 0) {
+		if (error != -EPROBE_DEFER)
+			dev_err(dev, "%s failed: %d\n", __func__, error);
+		return error;
+	}
+
+	return 0;
+}
+
+static int cdx_driver_remove(struct device *dev)
+{
+	struct cdx_driver *cdx_drv = to_cdx_driver(dev->driver);
+	struct cdx_device *cdx_dev = to_cdx_device(dev);
+	int ret;
+
+	if (cdx_drv->remove) {
+		ret = cdx_drv->remove(cdx_dev);
+		if (ret < 0) {
+			dev_err(dev, "%s failed: %d\n", __func__, ret);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static void cdx_driver_shutdown(struct device *dev)
+{
+	struct cdx_driver *cdx_drv = to_cdx_driver(dev->driver);
+	struct cdx_device *cdx_dev = to_cdx_device(dev);
+
+	cdx_drv->shutdown(cdx_dev);
+}
+
+int __cdx_driver_register(struct cdx_driver *cdx_driver,
+			  struct module *owner)
+{
+	int error;
+
+	cdx_driver->driver.owner = owner;
+	cdx_driver->driver.bus = &cdx_bus_type;
+
+	if (cdx_driver->probe)
+		cdx_driver->driver.probe = cdx_driver_probe;
+
+	if (cdx_driver->remove)
+		cdx_driver->driver.remove = cdx_driver_remove;
+
+	if (cdx_driver->shutdown)
+		cdx_driver->driver.shutdown = cdx_driver_shutdown;
+
+	error = driver_register(&cdx_driver->driver);
+	if (error < 0) {
+		pr_err("driver_register() failed for %s: %d\n",
+		       cdx_driver->driver.name, error);
+		return error;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(__cdx_driver_register);
+
+void cdx_driver_unregister(struct cdx_driver *cdx_driver)
+{
+	driver_unregister(&cdx_driver->driver);
+}
+EXPORT_SYMBOL_GPL(cdx_driver_unregister);
+
+static void cdx_device_release(struct device *dev)
+{
+	struct cdx_device *cdx_dev = to_cdx_device(dev);
+
+	kfree(cdx_dev);
+}
+
+int cdx_device_add(struct cdx_dev_params_t *dev_params)
+{
+	struct cdx_controller_t *cdx = dev_params->cdx;
+	struct device *parent = cdx->dev;
+	struct cdx_device *cdx_dev;
+	int ret;
+
+	cdx_dev = kzalloc(sizeof(*cdx_dev), GFP_KERNEL);
+	if (!cdx_dev) {
+		dev_err(parent,
+			"memory allocation for cdx dev failed\n");
+		return -ENOMEM;
+	}
+
+	/* Populate resource */
+	memcpy(cdx_dev->res, dev_params->res, sizeof(struct resource) *
+		dev_params->res_count);
+	cdx_dev->res_count = dev_params->res_count;
+
+	/* Populate CDX dev params */
+	cdx_dev->req_id = dev_params->req_id;
+	cdx_dev->vendor = dev_params->vendor;
+	cdx_dev->device = dev_params->device;
+	cdx_dev->bus_num = dev_params->bus_num;
+	cdx_dev->dev_num = dev_params->dev_num;
+	cdx_dev->cdx = dev_params->cdx;
+	cdx_dev->dma_mask = CDX_DEFAULT_DMA_MASK;
+
+	/* Initiaize generic device */
+	device_initialize(&cdx_dev->dev);
+	cdx_dev->dev.parent = parent;
+	cdx_dev->dev.bus = &cdx_bus_type;
+	cdx_dev->dev.dma_mask = &cdx_dev->dma_mask;
+	cdx_dev->dev.release = cdx_device_release;
+
+	/* Set Name */
+	dev_set_name(&cdx_dev->dev, "cdx-%02x:%02x", cdx_dev->bus_num,
+			cdx_dev->dev_num);
+
+	ret = device_add(&cdx_dev->dev);
+	if (ret != 0) {
+		dev_err(&cdx_dev->dev,
+			"cdx device add failed: %d", ret);
+		goto fail;
+	}
+
+	/* Reset the device before use */
+	ret = cdx->ops.reset_dev(cdx, cdx_dev->bus_num, cdx_dev->dev_num);
+	if (ret) {
+		dev_err(&cdx_dev->dev, "cdx device reset failed\n");
+		goto fail;
+	}
+
+	return 0;
+
+fail:
+	/*
+	 * Do not free cdx_dev here as it would be freed in
+	 * cdx_device_release() called from put_device().
+	 */
+	put_device(&cdx_dev->dev);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(cdx_device_add);
+
+int cdx_register_controller(struct cdx_controller_t *cdx)
+{
+	int ret;
+
+	/* Scan all the devices */
+	ret = cdx->ops.scan(cdx);
+	if (ret) {
+		dev_err(cdx->dev, "CDX scanning failed: %d\n", ret);
+		return ret;
+	}
+
+	cdx_controller = cdx;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(cdx_register_controller);
+
+void cdx_unregister_controller(struct cdx_controller_t *cdx)
+{
+	device_for_each_child(cdx->dev, NULL, cdx_unregister_device);
+	cdx_controller = NULL;
+}
+EXPORT_SYMBOL_GPL(cdx_unregister_controller);
+
+static int __init cdx_bus_init(void)
+{
+	return bus_register(&cdx_bus_type);
+}
+postcore_initcall(cdx_bus_init);
diff --git a/drivers/bus/cdx/cdx.h b/drivers/bus/cdx/cdx.h
new file mode 100644
index 000000000000..80496865ae9c
--- /dev/null
+++ b/drivers/bus/cdx/cdx.h
@@ -0,0 +1,66 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Header file for the CDX Bus
+ *
+ * Copyright (C) 2022, Advanced Micro Devices, Inc.
+ */
+
+#ifndef _CDX_H_
+#define _CDX_H_
+
+#include <linux/cdx/cdx_bus.h>
+
+/**
+ * struct cdx_dev_params_t - CDX device parameters
+ * @cdx: CDX controller assocated with the device
+ * @parent: Associated CDX controller
+ * @vendor: Vendor ID for CDX device
+ * @device: Device ID for CDX device
+ * @subsys_vendor: Sub vendor ID for CDX device
+ * @subsys_device: Sub device ID for CDX device
+ * @bus_num: Bus number for this CDX device
+ * @dev_num: Device number for this device
+ * @res: array of MMIO region entries
+ * @res_count: number of valid MMIO regions
+ * @req_id: Requestor ID associated with CDX device
+ */
+struct cdx_dev_params_t {
+	struct cdx_controller_t *cdx;
+	u16 vendor;
+	u16 device;
+	u16 subsys_vendor;
+	u16 subsys_device;
+	u8 bus_num;
+	u8 dev_num;
+	struct resource res[MAX_CDX_DEV_RESOURCES];
+	u8 res_count;
+	u32 req_id;
+};
+
+/**
+ * cdx_register_controller - Register a CDX controller and its ports
+ *		on the CDX bus.
+ * @cdx: The CDX controller to register
+ *
+ * Returns -errno on failure, 0 on success.
+ */
+int cdx_register_controller(struct cdx_controller_t *cdx);
+
+/**
+ * cdx_unregister_controller - Unregister a CDX controller
+ * @cdx: The CDX controller to unregister
+ */
+void cdx_unregister_controller(struct cdx_controller_t *cdx);
+
+/**
+ * cdx_device_add - Add a CDX device. This function adds a CDX device
+ *		on the CDX bus as per the device paramteres provided
+ *		by caller. It also creates and registers an associated
+ *		Linux generic device.
+ * @dev_params: device parameters associated with the device to be created.
+ *
+ * Returns -errno on failure, 0 on success.
+ */
+int cdx_device_add(struct cdx_dev_params_t *dev_params);
+
+#endif /* _CDX_H_ */
diff --git a/include/linux/cdx/cdx_bus.h b/include/linux/cdx/cdx_bus.h
new file mode 100644
index 000000000000..9e6872a03215
--- /dev/null
+++ b/include/linux/cdx/cdx_bus.h
@@ -0,0 +1,139 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * CDX bus public interface
+ *
+ * Copyright (C) 2022, Advanced Micro Devices, Inc.
+ *
+ */
+#ifndef _CDX_BUS_H_
+#define _CDX_BUS_H_
+
+#include <linux/mod_devicetable.h>
+#include <linux/device.h>
+
+#define MAX_CDX_DEV_RESOURCES	4
+
+/* Forward declaration for CDX controller */
+struct cdx_controller_t;
+
+typedef int (*cdx_scan_t)(struct cdx_controller_t *cdx);
+
+typedef int (*cdx_dev_reset_t)(struct cdx_controller_t *cdx,
+			       uint8_t bus_num, uint8_t dev_num);
+
+/**
+ * Callbacks supported by CDX controller.
+ * @scan: scan the devices on the controller
+ * @reset_dev: reset a CDX device
+ */
+struct cdx_ops_t {
+	cdx_scan_t scan;
+	cdx_dev_reset_t reset_dev;
+};
+
+/**
+ * struct cdx_controller: CDX controller object
+ * @dev: Linux device associated with the CDX controller.
+ * @priv: private data
+ * @ops: CDX controller ops
+ */
+struct cdx_controller_t {
+	struct device *dev;
+	void *priv;
+
+	struct cdx_ops_t ops;
+};
+
+/**
+ * struct cdx_device - CDX device object
+ * @dev: Linux driver model device object
+ * @cdx: CDX controller assocated with the device
+ * @vendor: Vendor ID for CDX device
+ * @device: Device ID for CDX device
+ * @bus_num: Bus number for this CDX device
+ * @dev_num: Device number for this device
+ * @res: array of MMIO region entries
+ * @res_count: number of valid MMIO regions
+ * @dma_mask: Default DMA mask
+ * @flags: CDX device flags
+ * @req_id: Requestor ID associated with CDX device
+ * @driver_override: driver name to force a match; do not set directly,
+ *                   because core frees it; use driver_set_override() to
+ *                   set or clear it.
+ */
+struct cdx_device {
+	struct device dev;
+	struct cdx_controller_t *cdx;
+	u16 vendor;
+	u16 device;
+	u8 bus_num;
+	u8 dev_num;
+	struct resource res[MAX_CDX_DEV_RESOURCES];
+	u8 res_count;
+	u64 dma_mask;
+	u16 flags;
+	u32 req_id;
+	const char *driver_override;
+};
+
+#define to_cdx_device(_dev) \
+	container_of(_dev, struct cdx_device, dev)
+
+/**
+ * struct cdx_driver - CDX device driver
+ * @driver: Generic device driver
+ * @match_id_table: table of supported device matching Ids
+ * @probe: Function called when a device is added
+ * @remove: Function called when a device is removed
+ * @shutdown: Function called at shutdown time to quiesce the device
+ * @suspend: Function called when a device is stopped
+ * @resume: Function called when a device is resumed
+ * @driver_managed_dma: Device driver doesn't use kernel DMA API for DMA.
+ *		For most device drivers, no need to care about this flag
+ *		as long as all DMAs are handled through the kernel DMA API.
+ *		For some special ones, for example VFIO drivers, they know
+ *		how to manage the DMA themselves and set this flag so that
+ *		the IOMMU layer will allow them to setup and manage their
+ *		own I/O address space.
+ */
+struct cdx_driver {
+	struct device_driver driver;
+	const struct cdx_device_id *match_id_table;
+	int (*probe)(struct cdx_device *dev);
+	int (*remove)(struct cdx_device *dev);
+	void (*shutdown)(struct cdx_device *dev);
+	int (*suspend)(struct cdx_device *dev, pm_message_t state);
+	int (*resume)(struct cdx_device *dev);
+	bool driver_managed_dma;
+};
+
+#define to_cdx_driver(_drv) \
+	container_of(_drv, struct cdx_driver, driver)
+
+/* Macro to avoid include chaining to get THIS_MODULE */
+#define cdx_driver_register(drv) \
+	__cdx_driver_register(drv, THIS_MODULE)
+
+/**
+ * __cdx_driver_register - registers a CDX device driver
+ */
+int __must_check __cdx_driver_register(struct cdx_driver *cdx_driver,
+				       struct module *owner);
+
+/**
+ * cdx_driver_unregister - unregisters a device driver from the
+ * CDX bus.
+ */
+void cdx_driver_unregister(struct cdx_driver *driver);
+
+extern struct bus_type cdx_bus_type;
+
+/**
+ * cdx_dev_reset - Reset CDX device
+ * @dev: device pointer
+ *
+ * Return 0 for success, -errno on failure
+ */
+int cdx_dev_reset(struct device *dev);
+
+#endif /* _CDX_BUS_H_ */
diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h
index 549590e9c644..9b94be83d53e 100644
--- a/include/linux/mod_devicetable.h
+++ b/include/linux/mod_devicetable.h
@@ -911,4 +911,17 @@  struct ishtp_device_id {
 	kernel_ulong_t driver_data;
 };
 
+/**
+ * struct cdx_device_id - CDX device identifier
+ * @vendor: vendor ID
+ * @device: Device ID
+ *
+ * Type of entries in the "device Id" table for CDX devices supported by
+ * a CDX device driver.
+ */
+struct cdx_device_id {
+	__u16 vendor;
+	__u16 device;
+};
+
 #endif /* LINUX_MOD_DEVICETABLE_H */
diff --git a/scripts/mod/devicetable-offsets.c b/scripts/mod/devicetable-offsets.c
index c0d3bcb99138..62dc988df84d 100644
--- a/scripts/mod/devicetable-offsets.c
+++ b/scripts/mod/devicetable-offsets.c
@@ -262,5 +262,9 @@  int main(void)
 	DEVID(ishtp_device_id);
 	DEVID_FIELD(ishtp_device_id, guid);
 
+	DEVID(cdx_device_id);
+	DEVID_FIELD(cdx_device_id, vendor);
+	DEVID_FIELD(cdx_device_id, device);
+
 	return 0;
 }
diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c
index 80d973144fde..c36e1f624e39 100644
--- a/scripts/mod/file2alias.c
+++ b/scripts/mod/file2alias.c
@@ -1452,6 +1452,17 @@  static int do_dfl_entry(const char *filename, void *symval, char *alias)
 	return 1;
 }
 
+/* Looks like: cdx:vNdN */
+static int do_cdx_entry(const char *filename, void *symval,
+			   char *alias)
+{
+	DEF_FIELD(symval, cdx_device_id, vendor);
+	DEF_FIELD(symval, cdx_device_id, device);
+
+	sprintf(alias, "cdx:v%08Xd%08Xd", vendor, device);
+	return 1;
+}
+
 /* Does namelen bytes of name exactly match the symbol? */
 static bool sym_is(const char *name, unsigned namelen, const char *symbol)
 {
@@ -1531,6 +1542,7 @@  static const struct devtable devtable[] = {
 	{"ssam", SIZE_ssam_device_id, do_ssam_entry},
 	{"dfl", SIZE_dfl_device_id, do_dfl_entry},
 	{"ishtp", SIZE_ishtp_device_id, do_ishtp_entry},
+	{"cdx", SIZE_cdx_device_id, do_cdx_entry},
 };
 
 /* Create MODULE_ALIAS() statements.