Quelle thunderbolt.h Sprache: C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Thunderbolt service API
*
* Copyright (C) 2014 Andreas Noever <andreas.noever@gmail.com>
* Copyright (C) 2017, Intel Corporation
* Authors: Michael Jamet <michael.jamet@intel.com>
*          Mika Westerberg <mika.westerberg@linux.intel.com>
*/

#ifndef THUNDERBOLT_H_
#define THUNDERBOLT_H_

#include <linux/types.h>

struct fwnode_handle;
struct device;

#if IS_REACHABLE(CONFIG_USB4)

#include <linux/device.h>
#include <linux/idr.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/mod_devicetable.h>
#include <linux/pci.h>
#include <linux/uuid.h>
#include <linux/workqueue.h>

enum tb_cfg_pkg_type {
TB_CFG_PKG_READ = 1,
TB_CFG_PKG_WRITE = 2,
TB_CFG_PKG_ERROR = 3,
TB_CFG_PKG_NOTIFY_ACK = 4,
TB_CFG_PKG_EVENT = 5,
TB_CFG_PKG_XDOMAIN_REQ = 6,
TB_CFG_PKG_XDOMAIN_RESP = 7,
TB_CFG_PKG_OVERRIDE = 8,
TB_CFG_PKG_RESET = 9,
TB_CFG_PKG_ICM_EVENT = 10,
TB_CFG_PKG_ICM_CMD = 11,
TB_CFG_PKG_ICM_RESP = 12,
};

/**
* enum tb_security_level - Thunderbolt security level
* @TB_SECURITY_NONE: No security, legacy mode
* @TB_SECURITY_USER: User approval required at minimum
* @TB_SECURITY_SECURE: One time saved key required at minimum
* @TB_SECURITY_DPONLY: Only tunnel Display port (and USB)
* @TB_SECURITY_USBONLY: Only tunnel USB controller of the connected
* Thunderbolt dock (and Display Port). All PCIe
* links downstream of the dock are removed.
* @TB_SECURITY_NOPCIE: For USB4 systems this level is used when the
* PCIe tunneling is disabled from the BIOS.
*/
enum tb_security_level {
TB_SECURITY_NONE,
TB_SECURITY_USER,
TB_SECURITY_SECURE,
TB_SECURITY_DPONLY,
TB_SECURITY_USBONLY,
TB_SECURITY_NOPCIE,
};

/**
* struct tb - main thunderbolt bus structure
* @dev: Domain device
* @lock: Big lock. Must be held when accessing any struct
*   tb_switch / struct tb_port.
* @nhi: Pointer to the NHI structure
* @ctl: Control channel for this domain
* @wq: Ordered workqueue for all domain specific work
* @root_switch: Root switch of this domain
* @cm_ops: Connection manager specific operations vector
* @index: Linux assigned domain number
* @security_level: Current security level
* @nboot_acl: Number of boot ACLs the domain supports
* @privdata: Private connection manager specific data
*/
struct tb {
struct device dev;
struct mutex lock;
struct tb_nhi *nhi;
struct tb_ctl *ctl;
struct workqueue_struct *wq;
struct tb_switch *root_switch;
const struct tb_cm_ops *cm_ops;
int index;
enum tb_security_level security_level;
size_t nboot_acl;
unsigned long privdata[];
};

extern const struct bus_type tb_bus_type;
extern const struct device_type tb_service_type;
extern const struct device_type tb_xdomain_type;

#define TB_LINKS_PER_PHY_PORT 2

static inline unsigned int tb_phy_port_from_link(unsigned int link)
{
return (link - 1) / TB_LINKS_PER_PHY_PORT;
}

/**
* struct tb_property_dir - XDomain property directory
* @uuid: Directory UUID or %NULL if root directory
* @properties: List of properties in this directory
*
* User needs to provide serialization if needed.
*/
struct tb_property_dir {
const uuid_t *uuid;
struct list_head properties;
};

enum tb_property_type {
TB_PROPERTY_TYPE_UNKNOWN = 0x00,
TB_PROPERTY_TYPE_DIRECTORY = 0x44,
TB_PROPERTY_TYPE_DATA = 0x64,
TB_PROPERTY_TYPE_TEXT = 0x74,
TB_PROPERTY_TYPE_VALUE = 0x76,
};

#define TB_PROPERTY_KEY_SIZE 8

/**
* struct tb_property - XDomain property
* @list: Used to link properties together in a directory
* @key: Key for the property (always terminated).
* @type: Type of the property
* @length: Length of the property data in dwords
* @value: Property value
*
* Users use @type to determine which field in @value is filled.
*/
struct tb_property {
struct list_head list;
char key[TB_PROPERTY_KEY_SIZE + 1];
enum tb_property_type type;
size_t length;
union {
  struct tb_property_dir *dir;
  u8 *data;
  char *text;
  u32 immediate;
} value;
};

struct tb_property_dir *tb_property_parse_dir(const u32 *block,
           size_t block_len);
ssize_t tb_property_format_dir(const struct tb_property_dir *dir, u32 *block,
          size_t block_len);
struct tb_property_dir *tb_property_copy_dir(const struct tb_property_dir *dir);
struct tb_property_dir *tb_property_create_dir(const uuid_t *uuid);
void tb_property_free_dir(struct tb_property_dir *dir);
int tb_property_add_immediate(struct tb_property_dir *parent, const char *key,
         u32 value);
int tb_property_add_data(struct tb_property_dir *parent, const char *key,
    const void *buf, size_t buflen);
int tb_property_add_text(struct tb_property_dir *parent, const char *key,
    const char *text);
int tb_property_add_dir(struct tb_property_dir *parent, const char *key,
   struct tb_property_dir *dir);
void tb_property_remove(struct tb_property *tb_property);
struct tb_property *tb_property_find(struct tb_property_dir *dir,
   const char *key, enum tb_property_type type);
struct tb_property *tb_property_get_next(struct tb_property_dir *dir,
      struct tb_property *prev);

#define tb_property_for_each(dir, property)   \
for (property = tb_property_get_next(dir, NULL); \
      property;      \
      property = tb_property_get_next(dir, property))

int tb_register_property_dir(const char *key, struct tb_property_dir *dir);
void tb_unregister_property_dir(const char *key, struct tb_property_dir *dir);

/**
* enum tb_link_width - Thunderbolt/USB4 link width
* @TB_LINK_WIDTH_SINGLE: Single lane link
* @TB_LINK_WIDTH_DUAL: Dual lane symmetric link
* @TB_LINK_WIDTH_ASYM_TX: Dual lane asymmetric Gen 4 link with 3 transmitters
* @TB_LINK_WIDTH_ASYM_RX: Dual lane asymmetric Gen 4 link with 3 receivers
*/
enum tb_link_width {
TB_LINK_WIDTH_SINGLE = BIT(0),
TB_LINK_WIDTH_DUAL = BIT(1),
TB_LINK_WIDTH_ASYM_TX = BIT(2),
TB_LINK_WIDTH_ASYM_RX = BIT(3),
};

/**
* struct tb_xdomain - Cross-domain (XDomain) connection
* @dev: XDomain device
* @tb: Pointer to the domain
* @remote_uuid: UUID of the remote domain (host)
* @local_uuid: Cached local UUID
* @route: Route string the other domain can be reached
* @vendor: Vendor ID of the remote domain
* @device: Device ID of the demote domain
* @local_max_hopid: Maximum input HopID of this host
* @remote_max_hopid: Maximum input HopID of the remote host
* @lock: Lock to serialize access to the following fields of this structure
* @vendor_name: Name of the vendor (or %NULL if not known)
* @device_name: Name of the device (or %NULL if not known)
* @link_speed: Speed of the link in Gb/s
* @link_width: Width of the downstream facing link
* @link_usb4: Downstream link is USB4
* @is_unplugged: The XDomain is unplugged
* @needs_uuid: If the XDomain does not have @remote_uuid it will be
* queried first
* @service_ids: Used to generate IDs for the services
* @in_hopids: Input HopIDs for DMA tunneling
* @out_hopids; Output HopIDs for DMA tunneling
* @local_property_block: Local block of properties
* @local_property_block_gen: Generation of @local_property_block
* @local_property_block_len: Length of the @local_property_block in dwords
* @remote_properties: Properties exported by the remote domain
* @remote_property_block_gen: Generation of @remote_properties
* @state: Next XDomain discovery state to run
* @state_work: Work used to run the next state
* @state_retries: Number of retries remain for the state
* @properties_changed_work: Work used to notify the remote domain that
*      our properties have changed
* @properties_changed_retries: Number of times left to send properties
* changed notification
* @bonding_possible: True if lane bonding is possible on local side
* @target_link_width: Target link width from the remote host
* @link: Root switch link the remote domain is connected (ICM only)
* @depth: Depth in the chain the remote domain is connected (ICM only)
*
* This structure represents connection across two domains (hosts).
* Each XDomain contains zero or more services which are exposed as
* &struct tb_service objects.
*
* Service drivers may access this structure if they need to enumerate
* non-standard properties but they need hold @lock when doing so
* because properties can be changed asynchronously in response to
* changes in the remote domain.
*/
struct tb_xdomain {
struct device dev;
struct tb *tb;
uuid_t *remote_uuid;
const uuid_t *local_uuid;
u64 route;
u16 vendor;
u16 device;
unsigned int local_max_hopid;
unsigned int remote_max_hopid;
struct mutex lock;
const char *vendor_name;
const char *device_name;
unsigned int link_speed;
enum tb_link_width link_width;
bool link_usb4;
bool is_unplugged;
bool needs_uuid;
struct ida service_ids;
struct ida in_hopids;
struct ida out_hopids;
u32 *local_property_block;
u32 local_property_block_gen;
u32 local_property_block_len;
struct tb_property_dir *remote_properties;
u32 remote_property_block_gen;
int state;
struct delayed_work state_work;
int state_retries;
struct delayed_work properties_changed_work;
int properties_changed_retries;
bool bonding_possible;
u8 target_link_width;
u8 link;
u8 depth;
};

int tb_xdomain_lane_bonding_enable(struct tb_xdomain *xd);
void tb_xdomain_lane_bonding_disable(struct tb_xdomain *xd);
int tb_xdomain_alloc_in_hopid(struct tb_xdomain *xd, int hopid);
void tb_xdomain_release_in_hopid(struct tb_xdomain *xd, int hopid);
int tb_xdomain_alloc_out_hopid(struct tb_xdomain *xd, int hopid);
void tb_xdomain_release_out_hopid(struct tb_xdomain *xd, int hopid);
int tb_xdomain_enable_paths(struct tb_xdomain *xd, int transmit_path,
       int transmit_ring, int receive_path,
       int receive_ring);
int tb_xdomain_disable_paths(struct tb_xdomain *xd, int transmit_path,
        int transmit_ring, int receive_path,
        int receive_ring);

static inline int tb_xdomain_disable_all_paths(struct tb_xdomain *xd)
{
return tb_xdomain_disable_paths(xd, -1, -1, -1, -1);
}

struct tb_xdomain *tb_xdomain_find_by_uuid(struct tb *tb, const uuid_t *uuid);
struct tb_xdomain *tb_xdomain_find_by_route(struct tb *tb, u64 route);

static inline struct tb_xdomain *
tb_xdomain_find_by_uuid_locked(struct tb *tb, const uuid_t *uuid)
{
struct tb_xdomain *xd;

mutex_lock(&tb->lock);
xd = tb_xdomain_find_by_uuid(tb, uuid);
mutex_unlock(&tb->lock);

return xd;
}

static inline struct tb_xdomain *
tb_xdomain_find_by_route_locked(struct tb *tb, u64 route)
{
struct tb_xdomain *xd;

mutex_lock(&tb->lock);
xd = tb_xdomain_find_by_route(tb, route);
mutex_unlock(&tb->lock);

return xd;
}

static inline struct tb_xdomain *tb_xdomain_get(struct tb_xdomain *xd)
{
if (xd)
  get_device(&xd->dev);
return xd;
}

static inline void tb_xdomain_put(struct tb_xdomain *xd)
{
if (xd)
  put_device(&xd->dev);
}

static inline bool tb_is_xdomain(const struct device *dev)
{
return dev->type == &tb_xdomain_type;
}

static inline struct tb_xdomain *tb_to_xdomain(struct device *dev)
{
if (tb_is_xdomain(dev))
  return container_of(dev, struct tb_xdomain, dev);
return NULL;
}

int tb_xdomain_response(struct tb_xdomain *xd, const void *response,
   size_t size, enum tb_cfg_pkg_type type);
int tb_xdomain_request(struct tb_xdomain *xd, const void *request,
         size_t request_size, enum tb_cfg_pkg_type request_type,
         void *response, size_t response_size,
         enum tb_cfg_pkg_type response_type,
         unsigned int timeout_msec);

/**
* tb_protocol_handler - Protocol specific handler
* @uuid: XDomain messages with this UUID are dispatched to this handler
* @callback: Callback called with the XDomain message. Returning %1
*       here tells the XDomain core that the message was handled
*       by this handler and should not be forwared to other
*       handlers.
* @data: Data passed with the callback
* @list: Handlers are linked using this
*
* Thunderbolt services can hook into incoming XDomain requests by
* registering protocol handler. Only limitation is that the XDomain
* discovery protocol UUID cannot be registered since it is handled by
* the core XDomain code.
*
* The @callback must check that the message is really directed to the
* service the driver implements.
*/
struct tb_protocol_handler {
const uuid_t *uuid;
int (*callback)(const void *buf, size_t size, void *data);
void *data;
struct list_head list;
};

int tb_register_protocol_handler(struct tb_protocol_handler *handler);
void tb_unregister_protocol_handler(struct tb_protocol_handler *handler);

/**
* struct tb_service - Thunderbolt service
* @dev: XDomain device
* @id: ID of the service (shown in sysfs)
* @key: Protocol key from the properties directory
* @prtcid: Protocol ID from the properties directory
* @prtcvers: Protocol version from the properties directory
* @prtcrevs: Protocol software revision from the properties directory
* @prtcstns: Protocol settings mask from the properties directory
* @debugfs_dir: Pointer to the service debugfs directory. Always created
* when debugfs is enabled. Can be used by service drivers to
* add their own entries under the service.
*
* Each domain exposes set of services it supports as collection of
* properties. For each service there will be one corresponding
* &struct tb_service. Service drivers are bound to these.
*/
struct tb_service {
struct device dev;
int id;
const char *key;
u32 prtcid;
u32 prtcvers;
u32 prtcrevs;
u32 prtcstns;
struct dentry *debugfs_dir;
};

static inline struct tb_service *tb_service_get(struct tb_service *svc)
{
if (svc)
  get_device(&svc->dev);
return svc;
}

static inline void tb_service_put(struct tb_service *svc)
{
if (svc)
  put_device(&svc->dev);
}

static inline bool tb_is_service(const struct device *dev)
{
return dev->type == &tb_service_type;
}

static inline struct tb_service *tb_to_service(struct device *dev)
{
if (tb_is_service(dev))
  return container_of(dev, struct tb_service, dev);
return NULL;
}

/**
* tb_service_driver - Thunderbolt service driver
* @driver: Driver structure
* @probe: Called when the driver is probed
* @remove: Called when the driver is removed (optional)
* @shutdown: Called at shutdown time to stop the service (optional)
* @id_table: Table of service identifiers the driver supports
*/
struct tb_service_driver {
struct device_driver driver;
int (*probe)(struct tb_service *svc, const struct tb_service_id *id);
void (*remove)(struct tb_service *svc);
void (*shutdown)(struct tb_service *svc);
const struct tb_service_id *id_table;
};

#define TB_SERVICE(key, id)    \
.match_flags = TBSVC_MATCH_PROTOCOL_KEY | \
         TBSVC_MATCH_PROTOCOL_ID,  \
.protocol_key = (key),    \
.protocol_id = (id)

int tb_register_service_driver(struct tb_service_driver *drv);
void tb_unregister_service_driver(struct tb_service_driver *drv);

static inline void *tb_service_get_drvdata(const struct tb_service *svc)
{
return dev_get_drvdata(&svc->dev);
}

static inline void tb_service_set_drvdata(struct tb_service *svc, void *data)
{
dev_set_drvdata(&svc->dev, data);
}

static inline struct tb_xdomain *tb_service_parent(struct tb_service *svc)
{
return tb_to_xdomain(svc->dev.parent);
}

/**
* struct tb_nhi - thunderbolt native host interface
* @lock: Must be held during ring creation/destruction. Is acquired by
*   interrupt_work when dispatching interrupts to individual rings.
* @pdev: Pointer to the PCI device
* @ops: NHI specific optional ops
* @iobase: MMIO space of the NHI
* @tx_rings: All Tx rings available on this host controller
* @rx_rings: All Rx rings available on this host controller
* @msix_ida: Used to allocate MSI-X vectors for rings
* @going_away: The host controller device is about to disappear so when
* this flag is set, avoid touching the hardware anymore.
* @iommu_dma_protection: An IOMMU will isolate external-facing ports.
* @interrupt_work: Work scheduled to handle ring interrupt when no
*     MSI-X is used.
* @hop_count: Number of rings (end point hops) supported by NHI.
* @quirks: NHI specific quirks if any
*/
struct tb_nhi {
spinlock_t lock;
struct pci_dev *pdev;
const struct tb_nhi_ops *ops;
void __iomem *iobase;
struct tb_ring **tx_rings;
struct tb_ring **rx_rings;
struct ida msix_ida;
bool going_away;
bool iommu_dma_protection;
struct work_struct interrupt_work;
u32 hop_count;
unsigned long quirks;
};

/**
* struct tb_ring - thunderbolt TX or RX ring associated with a NHI
* @lock: Lock serializing actions to this ring. Must be acquired after
*   nhi->lock.
* @nhi: Pointer to the native host controller interface
* @size: Size of the ring
* @hop: Hop (DMA channel) associated with this ring
* @head: Head of the ring (write next descriptor here)
* @tail: Tail of the ring (complete next descriptor here)
* @descriptors: Allocated descriptors for this ring
* @queue: Queue holding frames to be transferred over this ring
* @in_flight: Queue holding frames that are currently in flight
* @work: Interrupt work structure
* @is_tx: Is the ring Tx or Rx
* @running: Is the ring running
* @irq: MSI-X irq number if the ring uses MSI-X. %0 otherwise.
* @vector: MSI-X vector number the ring uses (only set if @irq is > 0)
* @flags: Ring specific flags
* @e2e_tx_hop: Transmit HopID when E2E is enabled. Only applicable to
* RX ring. For TX ring this should be set to %0.
* @sof_mask: Bit mask used to detect start of frame PDF
* @eof_mask: Bit mask used to detect end of frame PDF
* @start_poll: Called when ring interrupt is triggered to start
* polling. Passing %NULL keeps the ring in interrupt mode.
* @poll_data: Data passed to @start_poll
*/
struct tb_ring {
spinlock_t lock;
struct tb_nhi *nhi;
int size;
int hop;
int head;
int tail;
struct ring_desc *descriptors;
dma_addr_t descriptors_dma;
struct list_head queue;
struct list_head in_flight;
struct work_struct work;
bool is_tx:1;
bool running:1;
int irq;
u8 vector;
unsigned int flags;
int e2e_tx_hop;
u16 sof_mask;
u16 eof_mask;
void (*start_poll)(void *data);
void *poll_data;
};

/* Leave ring interrupt enabled on suspend */
#define RING_FLAG_NO_SUSPEND BIT(0)
/* Configure the ring to be in frame mode */
#define RING_FLAG_FRAME  BIT(1)
/* Enable end-to-end flow control */
#define RING_FLAG_E2E  BIT(2)

struct ring_frame;
typedef void (*ring_cb)(struct tb_ring *, struct ring_frame *, bool canceled);

/**
* enum ring_desc_flags - Flags for DMA ring descriptor
* %RING_DESC_ISOCH: Enable isonchronous DMA (Tx only)
* %RING_DESC_CRC_ERROR: In frame mode CRC check failed for the frame (Rx only)
* %RING_DESC_COMPLETED: Descriptor completed (set by NHI)
* %RING_DESC_POSTED: Always set this
* %RING_DESC_BUFFER_OVERRUN: RX buffer overrun
* %RING_DESC_INTERRUPT: Request an interrupt on completion
*/
enum ring_desc_flags {
RING_DESC_ISOCH = 0x1,
RING_DESC_CRC_ERROR = 0x1,
RING_DESC_COMPLETED = 0x2,
RING_DESC_POSTED = 0x4,
RING_DESC_BUFFER_OVERRUN = 0x04,
RING_DESC_INTERRUPT = 0x8,
};

/**
* struct ring_frame - For use with ring_rx/ring_tx
* @buffer_phy: DMA mapped address of the frame
* @callback: Callback called when the frame is finished (optional)
* @list: Frame is linked to a queue using this
* @size: Size of the frame in bytes (%0 means %4096)
* @flags: Flags for the frame (see &enum ring_desc_flags)
* @eof: End of frame protocol defined field
* @sof: Start of frame protocol defined field
*/
struct ring_frame {
dma_addr_t buffer_phy;
ring_cb callback;
struct list_head list;
u32 size:12;
u32 flags:12;
u32 eof:4;
u32 sof:4;
};

/* Minimum size for ring_rx */
#define TB_FRAME_SIZE  0x100

struct tb_ring *tb_ring_alloc_tx(struct tb_nhi *nhi, int hop, int size,
     unsigned int flags);
struct tb_ring *tb_ring_alloc_rx(struct tb_nhi *nhi, int hop, int size,
     unsigned int flags, int e2e_tx_hop,
     u16 sof_mask, u16 eof_mask,
     void (*start_poll)(void *), void *poll_data);
void tb_ring_start(struct tb_ring *ring);
void tb_ring_stop(struct tb_ring *ring);
void tb_ring_free(struct tb_ring *ring);

int __tb_ring_enqueue(struct tb_ring *ring, struct ring_frame *frame);

/**
* tb_ring_rx() - enqueue a frame on an RX ring
* @ring: Ring to enqueue the frame
* @frame: Frame to enqueue
*
* @frame->buffer, @frame->buffer_phy have to be set. The buffer must
* contain at least %TB_FRAME_SIZE bytes.
*
* @frame->callback will be invoked with @frame->size, @frame->flags,
* @frame->eof, @frame->sof set once the frame has been received.
*
* If ring_stop() is called after the packet has been enqueued
* @frame->callback will be called with canceled set to true.
*
* Return: Returns %-ESHUTDOWN if ring_stop has been called. Zero otherwise.
*/
static inline int tb_ring_rx(struct tb_ring *ring, struct ring_frame *frame)
{
WARN_ON(ring->is_tx);
return __tb_ring_enqueue(ring, frame);
}

/**
* tb_ring_tx() - enqueue a frame on an TX ring
* @ring: Ring the enqueue the frame
* @frame: Frame to enqueue
*
* @frame->buffer, @frame->buffer_phy, @frame->size, @frame->eof and
* @frame->sof have to be set.
*
* @frame->callback will be invoked with once the frame has been transmitted.
*
* If ring_stop() is called after the packet has been enqueued @frame->callback
* will be called with canceled set to true.
*
* Return: Returns %-ESHUTDOWN if ring_stop has been called. Zero otherwise.
*/
static inline int tb_ring_tx(struct tb_ring *ring, struct ring_frame *frame)
{
WARN_ON(!ring->is_tx);
return __tb_ring_enqueue(ring, frame);
}

/* Used only when the ring is in polling mode */
struct ring_frame *tb_ring_poll(struct tb_ring *ring);
void tb_ring_poll_complete(struct tb_ring *ring);

/**
* tb_ring_dma_device() - Return device used for DMA mapping
* @ring: Ring whose DMA device is retrieved
*
* Use this function when you are mapping DMA for buffers that are
* passed to the ring for sending/receiving.
*/
static inline struct device *tb_ring_dma_device(struct tb_ring *ring)
{
return &ring->nhi->pdev->dev;
}

bool usb4_usb3_port_match(struct device *usb4_port_dev,
     const struct fwnode_handle *usb3_port_fwnode);

#else /* CONFIG_USB4 */
static inline bool usb4_usb3_port_match(struct device *usb4_port_dev,
     const struct fwnode_handle *usb3_port_fwnode)
{
return false;
}
#endif /* CONFIG_USB4 */

#endif /* THUNDERBOLT_H_ */

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