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1/* SPDX-License-Identifier: GPL-2.02 *3 * CDX bus public interface4 *5 * Copyright (C) 2022-2023, Advanced Micro Devices, Inc.6 *7 */8 9#ifndef _CDX_BUS_H_10#define _CDX_BUS_H_11 12#include <linux/device.h>13#include <linux/list.h>14#include <linux/mod_devicetable.h>15#include <linux/msi.h>16 17#define MAX_CDX_DEV_RESOURCES 418#define CDX_CONTROLLER_ID_SHIFT 419#define CDX_BUS_NUM_MASK 0xF20 21/* Forward declaration for CDX controller */22struct cdx_controller;23 24enum {25 CDX_DEV_MSI_CONF,26 CDX_DEV_BUS_MASTER_CONF,27 CDX_DEV_RESET_CONF,28 CDX_DEV_MSI_ENABLE,29};30 31struct cdx_msi_config {32 u64 addr;33 u32 data;34 u16 msi_index;35};36 37struct cdx_device_config {38 u8 type;39 union {40 struct cdx_msi_config msi;41 bool bus_master_enable;42 bool msi_enable;43 };44};45 46typedef int (*cdx_bus_enable_cb)(struct cdx_controller *cdx, u8 bus_num);47 48typedef int (*cdx_bus_disable_cb)(struct cdx_controller *cdx, u8 bus_num);49 50typedef int (*cdx_scan_cb)(struct cdx_controller *cdx);51 52typedef int (*cdx_dev_configure_cb)(struct cdx_controller *cdx,53 u8 bus_num, u8 dev_num,54 struct cdx_device_config *dev_config);55 56/**57 * CDX_DEVICE - macro used to describe a specific CDX device58 * @vend: the 16 bit CDX Vendor ID59 * @dev: the 16 bit CDX Device ID60 *61 * This macro is used to create a struct cdx_device_id that matches a62 * specific device. The subvendor and subdevice fields will be set to63 * CDX_ANY_ID.64 */65#define CDX_DEVICE(vend, dev) \66 .vendor = (vend), .device = (dev), \67 .subvendor = CDX_ANY_ID, .subdevice = CDX_ANY_ID68 69/**70 * CDX_DEVICE_DRIVER_OVERRIDE - macro used to describe a CDX device with71 * override_only flags.72 * @vend: the 16 bit CDX Vendor ID73 * @dev: the 16 bit CDX Device ID74 * @driver_override: the 32 bit CDX Device override_only75 *76 * This macro is used to create a struct cdx_device_id that matches only a77 * driver_override device. The subvendor and subdevice fields will be set to78 * CDX_ANY_ID.79 */80#define CDX_DEVICE_DRIVER_OVERRIDE(vend, dev, driver_override) \81 .vendor = (vend), .device = (dev), .subvendor = CDX_ANY_ID,\82 .subdevice = CDX_ANY_ID, .override_only = (driver_override)83 84/**85 * struct cdx_ops - Callbacks supported by CDX controller.86 * @bus_enable: enable bus on the controller87 * @bus_disable: disable bus on the controller88 * @scan: scan the devices on the controller89 * @dev_configure: configuration like reset, master_enable,90 * msi_config etc for a CDX device91 */92struct cdx_ops {93 cdx_bus_enable_cb bus_enable;94 cdx_bus_disable_cb bus_disable;95 cdx_scan_cb scan;96 cdx_dev_configure_cb dev_configure;97};98 99/**100 * struct cdx_controller: CDX controller object101 * @dev: Linux device associated with the CDX controller.102 * @priv: private data103 * @msi_domain: MSI domain104 * @id: Controller ID105 * @controller_registered: controller registered with bus106 * @ops: CDX controller ops107 */108struct cdx_controller {109 struct device *dev;110 void *priv;111 struct irq_domain *msi_domain;112 u32 id;113 bool controller_registered;114 struct cdx_ops *ops;115};116 117/**118 * struct cdx_device - CDX device object119 * @dev: Linux driver model device object120 * @cdx: CDX controller associated with the device121 * @vendor: Vendor ID for CDX device122 * @device: Device ID for CDX device123 * @subsystem_vendor: Subsystem Vendor ID for CDX device124 * @subsystem_device: Subsystem Device ID for CDX device125 * @class: Class for the CDX device126 * @revision: Revision of the CDX device127 * @bus_num: Bus number for this CDX device128 * @dev_num: Device number for this device129 * @res: array of MMIO region entries130 * @res_attr: resource binary attribute131 * @debugfs_dir: debugfs directory for this device132 * @res_count: number of valid MMIO regions133 * @dma_mask: Default DMA mask134 * @flags: CDX device flags135 * @req_id: Requestor ID associated with CDX device136 * @is_bus: Is this bus device137 * @enabled: is this bus enabled138 * @msi_dev_id: MSI Device ID associated with CDX device139 * @num_msi: Number of MSI's supported by the device140 * @driver_override: driver name to force a match; do not set directly,141 * because core frees it; use driver_set_override() to142 * set or clear it.143 * @irqchip_lock: lock to synchronize irq/msi configuration144 * @msi_write_pending: MSI write pending for this device145 */146struct cdx_device {147 struct device dev;148 struct cdx_controller *cdx;149 u16 vendor;150 u16 device;151 u16 subsystem_vendor;152 u16 subsystem_device;153 u32 class;154 u8 revision;155 u8 bus_num;156 u8 dev_num;157 struct resource res[MAX_CDX_DEV_RESOURCES];158 struct bin_attribute *res_attr[MAX_CDX_DEV_RESOURCES];159 struct dentry *debugfs_dir;160 u8 res_count;161 u64 dma_mask;162 u16 flags;163 u32 req_id;164 bool is_bus;165 bool enabled;166 u32 msi_dev_id;167 u32 num_msi;168 const char *driver_override;169 struct mutex irqchip_lock;170 bool msi_write_pending;171};172 173#define to_cdx_device(_dev) \174 container_of(_dev, struct cdx_device, dev)175 176#define cdx_resource_start(dev, num) ((dev)->res[(num)].start)177#define cdx_resource_end(dev, num) ((dev)->res[(num)].end)178#define cdx_resource_flags(dev, num) ((dev)->res[(num)].flags)179#define cdx_resource_len(dev, num) \180 ((cdx_resource_start((dev), (num)) == 0 && \181 cdx_resource_end((dev), (num)) == \182 cdx_resource_start((dev), (num))) ? 0 : \183 (cdx_resource_end((dev), (num)) - \184 cdx_resource_start((dev), (num)) + 1))185/**186 * struct cdx_driver - CDX device driver187 * @driver: Generic device driver188 * @match_id_table: table of supported device matching Ids189 * @probe: Function called when a device is added190 * @remove: Function called when a device is removed191 * @shutdown: Function called at shutdown time to quiesce the device192 * @reset_prepare: Function called before is reset to notify driver193 * @reset_done: Function called after reset is complete to notify driver194 * @driver_managed_dma: Device driver doesn't use kernel DMA API for DMA.195 * For most device drivers, no need to care about this flag196 * as long as all DMAs are handled through the kernel DMA API.197 * For some special ones, for example VFIO drivers, they know198 * how to manage the DMA themselves and set this flag so that199 * the IOMMU layer will allow them to setup and manage their200 * own I/O address space.201 */202struct cdx_driver {203 struct device_driver driver;204 const struct cdx_device_id *match_id_table;205 int (*probe)(struct cdx_device *dev);206 int (*remove)(struct cdx_device *dev);207 void (*shutdown)(struct cdx_device *dev);208 void (*reset_prepare)(struct cdx_device *dev);209 void (*reset_done)(struct cdx_device *dev);210 bool driver_managed_dma;211};212 213#define to_cdx_driver(_drv) \214 container_of_const(_drv, struct cdx_driver, driver)215 216/* Macro to avoid include chaining to get THIS_MODULE */217#define cdx_driver_register(drv) \218 __cdx_driver_register(drv, THIS_MODULE)219 220/**221 * __cdx_driver_register - registers a CDX device driver222 * @cdx_driver: CDX driver to register223 * @owner: module owner224 *225 * Return: -errno on failure, 0 on success.226 */227int __must_check __cdx_driver_register(struct cdx_driver *cdx_driver,228 struct module *owner);229 230/**231 * cdx_driver_unregister - unregisters a device driver from the232 * CDX bus.233 * @cdx_driver: CDX driver to register234 */235void cdx_driver_unregister(struct cdx_driver *cdx_driver);236 237extern struct bus_type cdx_bus_type;238 239/**240 * cdx_dev_reset - Reset CDX device241 * @dev: device pointer242 *243 * Return: 0 for success, -errno on failure244 */245int cdx_dev_reset(struct device *dev);246 247/**248 * cdx_set_master - enables bus-mastering for CDX device249 * @cdx_dev: the CDX device to enable250 *251 * Return: 0 for success, -errno on failure252 */253int cdx_set_master(struct cdx_device *cdx_dev);254 255/**256 * cdx_clear_master - disables bus-mastering for CDX device257 * @cdx_dev: the CDX device to disable258 *259 * Return: 0 for success, -errno on failure260 */261int cdx_clear_master(struct cdx_device *cdx_dev);262 263#ifdef CONFIG_GENERIC_MSI_IRQ264/**265 * cdx_enable_msi - Enable MSI for the CDX device.266 * @cdx_dev: device pointer267 *268 * Return: 0 for success, -errno on failure269 */270int cdx_enable_msi(struct cdx_device *cdx_dev);271 272/**273 * cdx_disable_msi - Disable MSI for the CDX device.274 * @cdx_dev: device pointer275 */276void cdx_disable_msi(struct cdx_device *cdx_dev);277 278#else /* CONFIG_GENERIC_MSI_IRQ */279 280static inline int cdx_enable_msi(struct cdx_device *cdx_dev)281{282 return -ENODEV;283}284 285static inline void cdx_disable_msi(struct cdx_device *cdx_dev)286{287}288 289#endif /* CONFIG_GENERIC_MSI_IRQ */290 291#endif /* _CDX_BUS_H_ */292