/* SPDX-License-Identifier: GPL-2.0
*
* CDX bus public interface
*
* Copyright (C) 2022-2023, Advanced Micro Devices, Inc.
*
*/
#ifndef _CDX_BUS_H_
#define _CDX_BUS_H_
#include <linux/device.h>
#include <linux/list.h>
#include <linux/mod_devicetable.h>
#include <linux/msi.h>
#define MAX_CDX_DEV_RESOURCES 4
#define CDX_CONTROLLER_ID_SHIFT 4
#define CDX_BUS_NUM_MASK 0xF
/* Forward declaration for CDX controller */
struct cdx_controller;
enum {
CDX_DEV_MSI_CONF,
CDX_DEV_BUS_MASTER_CONF,
CDX_DEV_RESET_CONF,
CDX_DEV_MSI_ENABLE,
};
struct cdx_msi_config {
u64 addr;
u32 data;
u16 msi_index;
};
struct cdx_device_config {
u8 type;
union {
struct cdx_msi_config msi;
bool bus_master_enable;
bool msi_enable;
};
};
typedef int (*cdx_bus_enable_cb)(struct cdx_controller *cdx, u8 bus_num);
typedef int (*cdx_bus_disable_cb)(struct cdx_controller *cdx, u8 bus_num);
typedef int (*cdx_scan_cb)(struct cdx_controller *cdx);
typedef int (*cdx_dev_configure_cb)(struct cdx_controller *cdx,
u8 bus_num, u8 dev_num,
struct cdx_device_config *dev_config);
/**
* CDX_DEVICE - macro used to describe a specific CDX device
* @vend: the 16 bit CDX Vendor ID
* @dev: the 16 bit CDX Device ID
*
* This macro is used to create a struct cdx_device_id that matches a
* specific device. The subvendor and subdevice fields will be set to
* CDX_ANY_ID.
*/
#define CDX_DEVICE(vend, dev) \
.vendor = (vend), .device = (dev), \
.subvendor = CDX_ANY_ID, .subdevice = CDX_ANY_ID
/**
* CDX_DEVICE_DRIVER_OVERRIDE - macro used to describe a CDX device with
* override_only flags.
* @vend: the 16 bit CDX Vendor ID
* @dev: the 16 bit CDX Device ID
* @driver_override: the 32 bit CDX Device override_only
*
* This macro is used to create a struct cdx_device_id that matches only a
* driver_override device. The subvendor and subdevice fields will be set to
* CDX_ANY_ID.
*/
#define CDX_DEVICE_DRIVER_OVERRIDE(vend, dev, driver_override) \
.vendor = (vend), .device = (dev), .subvendor = CDX_ANY_ID,\
.subdevice = CDX_ANY_ID, .override_only = (driver_override)
/**
* struct cdx_ops - Callbacks supported by CDX controller.
* @bus_enable: enable bus on the controller
* @bus_disable: disable bus on the controller
* @scan: scan the devices on the controller
* @dev_configure: configuration like reset, master_enable,
* msi_config etc for a CDX device
*/
struct cdx_ops {
cdx_bus_enable_cb bus_enable;
cdx_bus_disable_cb bus_disable;
cdx_scan_cb scan;
cdx_dev_configure_cb dev_configure;
};
/**
* struct cdx_controller: CDX controller object
* @dev: Linux device associated with the CDX controller.
* @priv: private data
* @msi_domain: MSI domain
* @id: Controller ID
* @controller_registered: controller registered with bus
* @ops: CDX controller ops
*/
struct cdx_controller {
struct device *dev;
void *priv;
struct irq_domain *msi_domain;
u32 id;
bool controller_registered;
struct cdx_ops *ops;
};
/**
* struct cdx_device - CDX device object
* @dev: Linux driver model device object
* @cdx: CDX controller associated with the device
* @vendor: Vendor ID for CDX device
* @device: Device ID for CDX device
* @subsystem_vendor: Subsystem Vendor ID for CDX device
* @subsystem_device: Subsystem Device ID for CDX device
* @class: Class for the CDX device
* @revision: Revision of the CDX device
* @bus_num: Bus number for this CDX device
* @dev_num: Device number for this device
* @res: array of MMIO region entries
* @res_attr: resource binary attribute
* @debugfs_dir: debugfs directory for this device
* @res_count: number of valid MMIO regions
* @dma_mask: Default DMA mask
* @flags: CDX device flags
* @req_id: Requestor ID associated with CDX device
* @is_bus: Is this bus device
* @enabled: is this bus enabled
* @msi_dev_id: MSI Device ID associated with CDX device
* @num_msi: Number of MSI's supported by the 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.
* @irqchip_lock: lock to synchronize irq/msi configuration
* @msi_write_pending: MSI write pending for this device
*/
struct cdx_device {
struct device dev;
struct cdx_controller *cdx;
u16 vendor;
u16 device;
u16 subsystem_vendor;
u16 subsystem_device;
u32 class;
u8 revision;
u8 bus_num;
u8 dev_num;
struct resource res[MAX_CDX_DEV_RESOURCES];
struct bin_attribute *res_attr[MAX_CDX_DEV_RESOURCES];
struct dentry *debugfs_dir;
u8 res_count;
u64 dma_mask;
u16 flags;
u32 req_id;
bool is_bus;
bool enabled;
u32 msi_dev_id;
u32 num_msi;
const char *driver_override;
struct mutex irqchip_lock;
bool msi_write_pending;
};
#define to_cdx_device(_dev) \
container_of(_dev, struct cdx_device, dev)
#define cdx_resource_start(dev, num) ((dev)->res[(num)].start)
#define cdx_resource_end(dev, num) ((dev)->res[(num)].end)
#define cdx_resource_flags(dev, num) ((dev)->res[(num)].flags)
#define cdx_resource_len(dev, num) \
((cdx_resource_start((dev), (num)) == 0 && \
cdx_resource_end((dev), (num)) == \
cdx_resource_start((dev), (num))) ? 0 : \
(cdx_resource_end((dev), (num)) - \
cdx_resource_start((dev), (num)) + 1))
/**
* 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
* @reset_prepare: Function called before is reset to notify driver
* @reset_done: Function called after reset is complete to notify driver
* @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);
void (*reset_prepare)(struct cdx_device *dev);
void (*reset_done)(struct cdx_device *dev);
bool driver_managed_dma;
};
#define to_cdx_driver(_drv) \
container_of_const(_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
* @cdx_driver: CDX driver to register
* @owner: module owner
*
* Return: -errno on failure, 0 on success.
*/
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.
* @cdx_driver: CDX driver to register
*/
void cdx_driver_unregister(struct cdx_driver *cdx_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);
/**
* cdx_set_master - enables bus-mastering for CDX device
* @cdx_dev: the CDX device to enable
*
* Return: 0 for success, -errno on failure
*/
int cdx_set_master(struct cdx_device *cdx_dev);
/**
* cdx_clear_master - disables bus-mastering for CDX device
* @cdx_dev: the CDX device to disable
*
* Return: 0 for success, -errno on failure
*/
int cdx_clear_master(struct cdx_device *cdx_dev);
#ifdef CONFIG_GENERIC_MSI_IRQ
/**
* cdx_enable_msi - Enable MSI for the CDX device.
* @cdx_dev: device pointer
*
* Return: 0 for success, -errno on failure
*/
int cdx_enable_msi(struct cdx_device *cdx_dev);
/**
* cdx_disable_msi - Disable MSI for the CDX device.
* @cdx_dev: device pointer
*/
void cdx_disable_msi(struct cdx_device *cdx_dev);
#else /* CONFIG_GENERIC_MSI_IRQ */
static inline int cdx_enable_msi(struct cdx_device *cdx_dev)
{
return -ENODEV;
}
static inline void cdx_disable_msi(struct cdx_device *cdx_dev)
{
}
#endif /* CONFIG_GENERIC_MSI_IRQ */
#endif /* _CDX_BUS_H_ */
Codebase Browser
linux