/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * Tegra host1x Command DMA
 *
 * Copyright (c) 2010-2013, NVIDIA Corporation.
 */

#ifndef __HOST1X_CDMA_H
#define __HOST1X_CDMA_H

#include <linux/sched.h>
#include <linux/completion.h>
#include <linux/list.h>
#include <linux/workqueue.h>

struct host1x_syncpt;
struct host1x_userctx_timeout;
struct host1x_job;

/*
 * cdma
 *
 * This is in charge of a host command DMA channel.
 * Sends ops to a push buffer, and takes responsibility for unpinning
 * (& possibly freeing) of memory after those ops have completed.
 * Producer:
 *      begin
 *              push - send ops to the push buffer
 *      end - start command DMA and enqueue handles to be unpinned
 * Consumer:
 *      update - call to update sync queue and push buffer, unpin memory
 */

struct push_buffer {
        void *mapped;                   /* mapped pushbuffer memory */
        dma_addr_t dma;                 /* device address of pushbuffer */
        dma_addr_t phys;                /* physical address of pushbuffer */
        u32 fence;                      /* index we've written */
        u32 pos;                        /* index to write to */
        u32 size;
        u32 alloc_size;
};

struct buffer_timeout {
        struct delayed_work wq;         /* work queue */
        bool initialized;               /* timer one-time setup flag */
        struct host1x_syncpt *syncpt;   /* buffer completion syncpt */
        u32 syncpt_val;                 /* syncpt value when completed */
        ktime_t start_ktime;            /* starting time */
        /* context timeout information */
        struct host1x_client *client;
};

enum cdma_event {
        CDMA_EVENT_NONE,                /* not waiting for any event */
        CDMA_EVENT_SYNC_QUEUE_EMPTY,    /* wait for empty sync queue */
        CDMA_EVENT_PUSH_BUFFER_SPACE    /* wait for space in push buffer */
};

struct host1x_cdma {
        struct mutex lock;              /* controls access to shared state */
        struct completion complete;     /* signalled when event occurs */
        enum cdma_event event;          /* event that complete is waiting for */
        unsigned int slots_used;        /* pb slots used in current submit */
        unsigned int slots_free;        /* pb slots free in current submit */
        unsigned int first_get;         /* DMAGET value, where submit begins */
        unsigned int last_pos;          /* last value written to DMAPUT */
        struct push_buffer push_buffer; /* channel's push buffer */
        struct list_head sync_queue;    /* job queue */
        struct buffer_timeout timeout;  /* channel's timeout state/wq */
        bool running;
        bool torndown;
        struct work_struct update_work;
};

#define cdma_to_channel(cdma) container_of(cdma, struct host1x_channel, cdma)
#define cdma_to_host1x(cdma) dev_get_drvdata(cdma_to_channel(cdma)->dev->parent)
#define pb_to_cdma(pb) container_of(pb, struct host1x_cdma, push_buffer)

int host1x_cdma_init(struct host1x_cdma *cdma);
int host1x_cdma_deinit(struct host1x_cdma *cdma);
int host1x_cdma_begin(struct host1x_cdma *cdma, struct host1x_job *job);
void host1x_cdma_push(struct host1x_cdma *cdma, u32 op1, u32 op2);
void host1x_cdma_push_wide(struct host1x_cdma *cdma, u32 op1, u32 op2,
                           u32 op3, u32 op4);
void host1x_cdma_end(struct host1x_cdma *cdma, struct host1x_job *job);
void host1x_cdma_update(struct host1x_cdma *cdma);
void host1x_cdma_peek(struct host1x_cdma *cdma, u32 dmaget, int slot,
                      u32 *out);
unsigned int host1x_cdma_wait_locked(struct host1x_cdma *cdma,
                                     enum cdma_event event);
void host1x_cdma_update_sync_queue(struct host1x_cdma *cdma,
                                   struct device *dev);
#endif