Quellverzeichnis  tunnel.h   Interaktion und
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/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Thunderbolt driver - Tunneling support
 *
 * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
 * Copyright (C) 2019, Intel Corporation
 */

#ifndef TB_TUNNEL_H_
#define TB_TUNNEL_H_

#include "tb.h"

enum tb_tunnel_type {
 TB_TUNNEL_PCI,
 TB_TUNNEL_DP,
 TB_TUNNEL_DMA,
 TB_TUNNEL_USB3,
};

/**
 * enum tb_tunnel_state - State of a tunnel
 * @TB_TUNNEL_INACTIVE: tb_tunnel_activate() is not called for the tunnel
 * @TB_TUNNEL_ACTIVATING: tb_tunnel_activate() returned successfully for the tunnel
 * @TB_TUNNEL_ACTIVE: The tunnel is fully active
 */
enum tb_tunnel_state {
 TB_TUNNEL_INACTIVE,
 TB_TUNNEL_ACTIVATING,
 TB_TUNNEL_ACTIVE,
};

/**
 * struct tb_tunnel - Tunnel between two ports
 * @kref: Reference count
 * @tb: Pointer to the domain
 * @src_port: Source port of the tunnel
 * @dst_port: Destination port of the tunnel. For discovered incomplete
 *       tunnels may be %NULL or null adapter port instead.
 * @paths: All paths required by the tunnel
 * @npaths: Number of paths in @paths
 * @pre_activate: Optional tunnel specific initialization called before
 *   activation. Can touch hardware.
 * @activate: Optional tunnel specific activation/deactivation
 * @post_deactivate: Optional tunnel specific de-initialization called
 *      after deactivation. Can touch hardware.
 * @destroy: Optional tunnel specific callback called when the tunnel
 *      memory is being released. Should not touch hardware.
 * @maximum_bandwidth: Returns maximum possible bandwidth for this tunnel
 * @allocated_bandwidth: Return how much bandwidth is allocated for the tunnel
 * @alloc_bandwidth: Change tunnel bandwidth allocation
 * @consumed_bandwidth: Return how much bandwidth the tunnel consumes
 * @release_unused_bandwidth: Release all unused bandwidth
 * @reclaim_available_bandwidth: Reclaim back available bandwidth
 * @list: Tunnels are linked using this field
 * @type: Type of the tunnel
 * @state: Current state of the tunnel
 * @max_up: Maximum upstream bandwidth (Mb/s) available for the tunnel.
 *     Only set if the bandwidth needs to be limited.
 * @max_down: Maximum downstream bandwidth (Mb/s) available for the tunnel.
 *       Only set if the bandwidth needs to be limited.
 * @allocated_up: Allocated upstream bandwidth (only for USB3)
 * @allocated_down: Allocated downstream bandwidth (only for USB3)
 * @bw_mode: DP bandwidth allocation mode registers can be used to
 *      determine consumed and allocated bandwidth
 * @dprx_started: DPRX negotiation was started (tb_dp_dprx_start() was called for it)
 * @dprx_canceled: Was DPRX capabilities read poll canceled
 * @dprx_timeout: If set DPRX capabilities read poll work will timeout after this passes
 * @dprx_work: Worker that is scheduled to poll completion of DPRX capabilities read
 * @callback: Optional callback called when DP tunnel is fully activated
 * @callback_data: Optional data for @callback
 */
struct tb_tunnel {
 struct kref kref;
 struct tb *tb;
 struct tb_port *src_port;
 struct tb_port *dst_port;
 struct tb_path **paths;
 size_t npaths;
 int (*pre_activate)(struct tb_tunnel *tunnel);
 int (*activate)(struct tb_tunnel *tunnel, bool activate);
 void (*post_deactivate)(struct tb_tunnel *tunnel);
 void (*destroy)(struct tb_tunnel *tunnel);
 int (*maximum_bandwidth)(struct tb_tunnel *tunnel, int *max_up,
     int *max_down);
 int (*allocated_bandwidth)(struct tb_tunnel *tunnel, int *allocated_up,
       int *allocated_down);
 int (*alloc_bandwidth)(struct tb_tunnel *tunnel, int *alloc_up,
          int *alloc_down);
 int (*consumed_bandwidth)(struct tb_tunnel *tunnel, int *consumed_up,
      int *consumed_down);
 int (*release_unused_bandwidth)(struct tb_tunnel *tunnel);
 void (*reclaim_available_bandwidth)(struct tb_tunnel *tunnel,
         int *available_up,
         int *available_down);
 struct list_head list;
 enum tb_tunnel_type type;
 enum tb_tunnel_state state;
 int max_up;
 int max_down;
 int allocated_up;
 int allocated_down;
 bool bw_mode;
 bool dprx_started;
 bool dprx_canceled;
 ktime_t dprx_timeout;
 struct delayed_work dprx_work;
 void (*callback)(struct tb_tunnel *tunnel, void *data);
 void *callback_data;
};

struct tb_tunnel *tb_tunnel_discover_pci(struct tb *tb, struct tb_port *down,
      bool alloc_hopid);
struct tb_tunnel *tb_tunnel_alloc_pci(struct tb *tb, struct tb_port *up,
          struct tb_port *down);
bool tb_tunnel_reserved_pci(struct tb_port *port, int *reserved_up,
       int *reserved_down);
struct tb_tunnel *tb_tunnel_discover_dp(struct tb *tb, struct tb_port *in,
     bool alloc_hopid);
struct tb_tunnel *tb_tunnel_alloc_dp(struct tb *tb, struct tb_port *in,
         struct tb_port *out, int link_nr,
         int max_up, int max_down,
         void (*callback)(struct tb_tunnel *, void *),
         void *callback_data);
struct tb_tunnel *tb_tunnel_alloc_dma(struct tb *tb, struct tb_port *nhi,
          struct tb_port *dst, int transmit_path,
          int transmit_ring, int receive_path,
          int receive_ring);
bool tb_tunnel_match_dma(const struct tb_tunnel *tunnel, int transmit_path,
    int transmit_ring, int receive_path, int receive_ring);
struct tb_tunnel *tb_tunnel_discover_usb3(struct tb *tb, struct tb_port *down,
       bool alloc_hopid);
struct tb_tunnel *tb_tunnel_alloc_usb3(struct tb *tb, struct tb_port *up,
           struct tb_port *down, int max_up,
           int max_down);

void tb_tunnel_put(struct tb_tunnel *tunnel);
int tb_tunnel_activate(struct tb_tunnel *tunnel);
void tb_tunnel_deactivate(struct tb_tunnel *tunnel);

/**
 * tb_tunnel_is_active() - Is tunnel fully activated
 * @tunnel: Tunnel to check
 *
 * Returns %true if @tunnel is fully activated. For other than DP
 * tunnels this is pretty much once tb_tunnel_activate() returns
 * successfully. However, for DP tunnels this returns %true only once the
 * DPRX capabilities read has been issued successfully.
 */
static inline bool tb_tunnel_is_active(const struct tb_tunnel *tunnel)
{
 return tunnel->state == TB_TUNNEL_ACTIVE;
}

bool tb_tunnel_is_invalid(struct tb_tunnel *tunnel);
bool tb_tunnel_port_on_path(const struct tb_tunnel *tunnel,
       const struct tb_port *port);
int tb_tunnel_maximum_bandwidth(struct tb_tunnel *tunnel, int *max_up,
    int *max_down);
int tb_tunnel_allocated_bandwidth(struct tb_tunnel *tunnel, int *allocated_up,
      int *allocated_down);
int tb_tunnel_alloc_bandwidth(struct tb_tunnel *tunnel, int *alloc_up,
         int *alloc_down);
int tb_tunnel_consumed_bandwidth(struct tb_tunnel *tunnel, int *consumed_up,
     int *consumed_down);
int tb_tunnel_release_unused_bandwidth(struct tb_tunnel *tunnel);
void tb_tunnel_reclaim_available_bandwidth(struct tb_tunnel *tunnel,
        int *available_up,
        int *available_down);

static inline bool tb_tunnel_is_pci(const struct tb_tunnel *tunnel)
{
 return tunnel->type == TB_TUNNEL_PCI;
}

static inline bool tb_tunnel_is_dp(const struct tb_tunnel *tunnel)
{
 return tunnel->type == TB_TUNNEL_DP;
}

static inline bool tb_tunnel_is_dma(const struct tb_tunnel *tunnel)
{
 return tunnel->type == TB_TUNNEL_DMA;
}

static inline bool tb_tunnel_is_usb3(const struct tb_tunnel *tunnel)
{
 return tunnel->type == TB_TUNNEL_USB3;
}

static inline bool tb_tunnel_direction_downstream(const struct tb_tunnel *tunnel)
{
 return tb_port_path_direction_downstream(tunnel->src_port,
       tunnel->dst_port);
}

/**
 * enum tb_tunnel_event - Tunnel related events
 * @TB_TUNNEL_ACTIVATED: A tunnel was activated
 * @TB_TUNNEL_CHANGED: There is a tunneling change in the domain. Includes
 *        full %TUNNEL_DETAILS if the tunnel in question is known
 *        (ICM does not provide that information).
 * @TB_TUNNEL_DEACTIVATED: A tunnel was torn down
 * @TB_TUNNEL_LOW_BANDWIDTH: Tunnel bandwidth is not optimal
 * @TB_TUNNEL_NO_BANDWIDTH: There is not enough bandwidth for a tunnel
 */
enum tb_tunnel_event {
 TB_TUNNEL_ACTIVATED,
 TB_TUNNEL_CHANGED,
 TB_TUNNEL_DEACTIVATED,
 TB_TUNNEL_LOW_BANDWIDTH,
 TB_TUNNEL_NO_BANDWIDTH,
};

void tb_tunnel_event(struct tb *tb, enum tb_tunnel_event event,
       enum tb_tunnel_type type,
       const struct tb_port *src_port,
       const struct tb_port *dst_port);

const char *tb_tunnel_type_name(const struct tb_tunnel *tunnel);

#define __TB_TUNNEL_PRINT(level, tunnel, fmt, arg...)                   \
 do {                                                            \
  struct tb_tunnel *__tunnel = (tunnel);                  \
  level(__tunnel->tb, "%llx:%u <-> %llx:%u (%s): " fmt,   \
        tb_route(__tunnel->src_port->sw),                 \
        __tunnel->src_port->port,                         \
        tb_route(__tunnel->dst_port->sw),                 \
        __tunnel->dst_port->port,                         \
        tb_tunnel_type_name(__tunnel),   \
        ## arg);                                          \
 } while (0)

#define tb_tunnel_WARN(tunnel, fmt, arg...) \
 __TB_TUNNEL_PRINT(tb_WARN, tunnel, fmt, ##arg)
#define tb_tunnel_warn(tunnel, fmt, arg...) \
 __TB_TUNNEL_PRINT(tb_warn, tunnel, fmt, ##arg)
#define tb_tunnel_info(tunnel, fmt, arg...) \
 __TB_TUNNEL_PRINT(tb_info, tunnel, fmt, ##arg)
#define tb_tunnel_dbg(tunnel, fmt, arg...) \
 __TB_TUNNEL_PRINT(tb_dbg, tunnel, fmt, ##arg)

#endif