/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * O(1) TX queue with built-in allocator for ST-Ericsson CW1200 drivers
 *
 * Copyright (c) 2010, ST-Ericsson
 * Author: Dmitry Tarnyagin <dmitry.tarnyagin@lockless.no>
 */

#ifndef CW1200_QUEUE_H_INCLUDED
#define CW1200_QUEUE_H_INCLUDED

/* private */ struct cw1200_queue_item;

/* extern */ struct sk_buff;
/* extern */ struct wsm_tx;
/* extern */ struct cw1200_common;
/* extern */ struct ieee80211_tx_queue_stats;
/* extern */ struct cw1200_txpriv;

/* forward */ struct cw1200_queue_stats;

typedef void (*cw1200_queue_skb_dtor_t)(struct cw1200_common *priv,
                                        struct sk_buff *skb,
                                        const struct cw1200_txpriv *txpriv);

struct cw1200_queue {
        struct cw1200_queue_stats *stats;
        size_t                  capacity;
        size_t                  num_queued;
        size_t                  num_pending;
        size_t                  num_sent;
        struct cw1200_queue_item *pool;
        struct list_head        queue;
        struct list_head        free_pool;
        struct list_head        pending;
        int                     tx_locked_cnt;
        int                     *link_map_cache;
        bool                    overfull;
        spinlock_t              lock; /* Protect queue entry */
        u8                      queue_id;
        u8                      generation;
        struct timer_list       gc;
        unsigned long           ttl;
};

struct cw1200_queue_stats {
        spinlock_t              lock; /* Protect stats entry */
        int                     *link_map_cache;
        int                     num_queued;
        size_t                  map_capacity;
        wait_queue_head_t       wait_link_id_empty;
        cw1200_queue_skb_dtor_t skb_dtor;
        struct cw1200_common    *priv;
};

struct cw1200_txpriv {
        u8 link_id;
        u8 raw_link_id;
        u8 tid;
        u8 rate_id;
        u8 offset;
};

int cw1200_queue_stats_init(struct cw1200_queue_stats *stats,
                            size_t map_capacity,
                            cw1200_queue_skb_dtor_t skb_dtor,
                            struct cw1200_common *priv);
int cw1200_queue_init(struct cw1200_queue *queue,
                      struct cw1200_queue_stats *stats,
                      u8 queue_id,
                      size_t capacity,
                      unsigned long ttl);
int cw1200_queue_clear(struct cw1200_queue *queue);
void cw1200_queue_stats_deinit(struct cw1200_queue_stats *stats);
void cw1200_queue_deinit(struct cw1200_queue *queue);

size_t cw1200_queue_get_num_queued(struct cw1200_queue *queue,
                                   u32 link_id_map);
int cw1200_queue_put(struct cw1200_queue *queue,
                     struct sk_buff *skb,
                     struct cw1200_txpriv *txpriv);
int cw1200_queue_get(struct cw1200_queue *queue,
                     u32 link_id_map,
                     struct wsm_tx **tx,
                     struct ieee80211_tx_info **tx_info,
                     const struct cw1200_txpriv **txpriv);
int cw1200_queue_requeue(struct cw1200_queue *queue, u32 packet_id);
int cw1200_queue_remove(struct cw1200_queue *queue,
                        u32 packet_id);
int cw1200_queue_get_skb(struct cw1200_queue *queue, u32 packet_id,
                         struct sk_buff **skb,
                         const struct cw1200_txpriv **txpriv);
void cw1200_queue_lock(struct cw1200_queue *queue);
void cw1200_queue_unlock(struct cw1200_queue *queue);
bool cw1200_queue_get_xmit_timestamp(struct cw1200_queue *queue,
                                     unsigned long *timestamp,
                                     u32 pending_frame_id);

bool cw1200_queue_stats_is_empty(struct cw1200_queue_stats *stats,
                                 u32 link_id_map);

static inline u8 cw1200_queue_get_queue_id(u32 packet_id)
{
        return (packet_id >> 16) & 0xFF;
}

static inline u8 cw1200_queue_get_generation(u32 packet_id)
{
        return (packet_id >>  8) & 0xFF;
}

#endif /* CW1200_QUEUE_H_INCLUDED */