root/drivers/gpu/host1x/syncpt.h
/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * Tegra host1x Syncpoints
 *
 * Copyright (c) 2010-2013, NVIDIA Corporation.
 */

#ifndef __HOST1X_SYNCPT_H
#define __HOST1X_SYNCPT_H

#include <linux/atomic.h>
#include <linux/host1x.h>
#include <linux/kernel.h>
#include <linux/kref.h>
#include <linux/sched.h>

#include "fence.h"
#include "intr.h"

struct host1x;

/* Reserved for replacing an expired wait with a NOP */
#define HOST1X_SYNCPT_RESERVED                  0

struct host1x_syncpt_base {
        unsigned int id;
        bool requested;
};

struct host1x_syncpt {
        struct kref ref;

        unsigned int id;
        atomic_t min_val;
        atomic_t max_val;
        u32 base_val;
        const char *name;
        bool client_managed;
        struct host1x *host;
        struct host1x_syncpt_base *base;

        /* interrupt data */
        struct host1x_fence_list fences;

        /*
         * If a submission incrementing this syncpoint fails, lock it so that
         * further submission cannot be made until application has handled the
         * failure.
         */
        bool locked;
};

/* Initialize sync point array  */
int host1x_syncpt_init(struct host1x *host);

/*  Free sync point array */
void host1x_syncpt_deinit(struct host1x *host);

/* Return number of sync point supported. */
unsigned int host1x_syncpt_nb_pts(struct host1x *host);

/* Return number of wait bases supported. */
unsigned int host1x_syncpt_nb_bases(struct host1x *host);

/* Return number of mlocks supported. */
unsigned int host1x_syncpt_nb_mlocks(struct host1x *host);

/*
 * Check sync point sanity. If max is larger than min, there have too many
 * sync point increments.
 *
 * Client managed sync point are not tracked.
 * */
static inline bool host1x_syncpt_check_max(struct host1x_syncpt *sp, u32 real)
{
        u32 max;
        if (sp->client_managed)
                return true;
        max = host1x_syncpt_read_max(sp);
        return (s32)(max - real) >= 0;
}

/* Return true if sync point is client managed. */
static inline bool host1x_syncpt_client_managed(struct host1x_syncpt *sp)
{
        return sp->client_managed;
}

/*
 * Returns true if syncpoint min == max, which means that there are no
 * outstanding operations.
 */
static inline bool host1x_syncpt_idle(struct host1x_syncpt *sp)
{
        int min, max;
        smp_rmb();
        min = atomic_read(&sp->min_val);
        max = atomic_read(&sp->max_val);
        return (min == max);
}

/* Load current value from hardware to the shadow register. */
u32 host1x_syncpt_load(struct host1x_syncpt *sp);

/* Check if the given syncpoint value has already passed */
bool host1x_syncpt_is_expired(struct host1x_syncpt *sp, u32 thresh);

/* Save host1x sync point state into shadow registers. */
void host1x_syncpt_save(struct host1x *host);

/* Reset host1x sync point state from shadow registers. */
void host1x_syncpt_restore(struct host1x *host);

/* Read current wait base value into shadow register and return it. */
u32 host1x_syncpt_load_wait_base(struct host1x_syncpt *sp);

/* Indicate future operations by incrementing the sync point max. */
u32 host1x_syncpt_incr_max(struct host1x_syncpt *sp, u32 incrs);

/* Check if sync point id is valid. */
static inline int host1x_syncpt_is_valid(struct host1x_syncpt *sp)
{
        return sp->id < host1x_syncpt_nb_pts(sp->host);
}

static inline void host1x_syncpt_set_locked(struct host1x_syncpt *sp)
{
        sp->locked = true;
}

#endif