linux/drivers/gpu/host1x/syncpt.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Tegra host1x Syncpoints
 *
 * Copyright (c) 2010-2015, NVIDIA Corporation.
 */

#include <linux/module.h>
#include <linux/device.h>
#include <linux/dma-fence.h>
#include <linux/slab.h>

#include <trace/events/host1x.h>

#include "syncpt.h"
#include "dev.h"
#include "intr.h"
#include "debug.h"

#define SYNCPT_CHECK_PERIOD …
#define MAX_STUCK_CHECK_COUNT …

static struct host1x_syncpt_base *
host1x_syncpt_base_request(struct host1x *host)
{ … }

static void host1x_syncpt_base_free(struct host1x_syncpt_base *base)
{ … }

/**
 * host1x_syncpt_alloc() - allocate a syncpoint
 * @host: host1x device data
 * @flags: bitfield of HOST1X_SYNCPT_* flags
 * @name: name for the syncpoint for use in debug prints
 *
 * Allocates a hardware syncpoint for the caller's use. The caller then has
 * the sole authority to mutate the syncpoint's value until it is freed again.
 *
 * If no free syncpoints are available, or a NULL name was specified, returns
 * NULL.
 */
struct host1x_syncpt *host1x_syncpt_alloc(struct host1x *host,
					  unsigned long flags,
					  const char *name)
{ … }
EXPORT_SYMBOL(…);

/**
 * host1x_syncpt_id() - retrieve syncpoint ID
 * @sp: host1x syncpoint
 *
 * Given a pointer to a struct host1x_syncpt, retrieves its ID. This ID is
 * often used as a value to program into registers that control how hardware
 * blocks interact with syncpoints.
 */
u32 host1x_syncpt_id(struct host1x_syncpt *sp)
{ … }
EXPORT_SYMBOL(…);

/**
 * host1x_syncpt_incr_max() - update the value sent to hardware
 * @sp: host1x syncpoint
 * @incrs: number of increments
 */
u32 host1x_syncpt_incr_max(struct host1x_syncpt *sp, u32 incrs)
{ … }
EXPORT_SYMBOL(…);

 /*
 * Write cached syncpoint and waitbase values to hardware.
 */
void host1x_syncpt_restore(struct host1x *host)
{ … }

/*
 * Update the cached syncpoint and waitbase values by reading them
 * from the registers.
  */
void host1x_syncpt_save(struct host1x *host)
{ … }

/*
 * Updates the cached syncpoint value by reading a new value from the hardware
 * register
 */
u32 host1x_syncpt_load(struct host1x_syncpt *sp)
{ … }

/*
 * Get the current syncpoint base
 */
u32 host1x_syncpt_load_wait_base(struct host1x_syncpt *sp)
{ … }

/**
 * host1x_syncpt_incr() - increment syncpoint value from CPU, updating cache
 * @sp: host1x syncpoint
 */
int host1x_syncpt_incr(struct host1x_syncpt *sp)
{ … }
EXPORT_SYMBOL(…);

/**
 * host1x_syncpt_wait() - wait for a syncpoint to reach a given value
 * @sp: host1x syncpoint
 * @thresh: threshold
 * @timeout: maximum time to wait for the syncpoint to reach the given value
 * @value: return location for the syncpoint value
 */
int host1x_syncpt_wait(struct host1x_syncpt *sp, u32 thresh, long timeout,
		       u32 *value)
{ … }
EXPORT_SYMBOL(…);

/*
 * Returns true if syncpoint is expired, false if we may need to wait
 */
bool host1x_syncpt_is_expired(struct host1x_syncpt *sp, u32 thresh)
{ … }

int host1x_syncpt_init(struct host1x *host)
{ … }

/**
 * host1x_syncpt_request() - request a syncpoint
 * @client: client requesting the syncpoint
 * @flags: flags
 *
 * host1x client drivers can use this function to allocate a syncpoint for
 * subsequent use. A syncpoint returned by this function will be reserved for
 * use by the client exclusively. When no longer using a syncpoint, a host1x
 * client driver needs to release it using host1x_syncpt_put().
 */
struct host1x_syncpt *host1x_syncpt_request(struct host1x_client *client,
					    unsigned long flags)
{ … }
EXPORT_SYMBOL(…);

static void syncpt_release(struct kref *ref)
{ … }

/**
 * host1x_syncpt_put() - free a requested syncpoint
 * @sp: host1x syncpoint
 *
 * Release a syncpoint previously allocated using host1x_syncpt_request(). A
 * host1x client driver should call this when the syncpoint is no longer in
 * use.
 */
void host1x_syncpt_put(struct host1x_syncpt *sp)
{ … }
EXPORT_SYMBOL(…);

void host1x_syncpt_deinit(struct host1x *host)
{ … }

/**
 * host1x_syncpt_read_max() - read maximum syncpoint value
 * @sp: host1x syncpoint
 *
 * The maximum syncpoint value indicates how many operations there are in
 * queue, either in channel or in a software thread.
 */
u32 host1x_syncpt_read_max(struct host1x_syncpt *sp)
{ … }
EXPORT_SYMBOL(…);

/**
 * host1x_syncpt_read_min() - read minimum syncpoint value
 * @sp: host1x syncpoint
 *
 * The minimum syncpoint value is a shadow of the current sync point value in
 * hardware.
 */
u32 host1x_syncpt_read_min(struct host1x_syncpt *sp)
{ … }
EXPORT_SYMBOL(…);

/**
 * host1x_syncpt_read() - read the current syncpoint value
 * @sp: host1x syncpoint
 */
u32 host1x_syncpt_read(struct host1x_syncpt *sp)
{ … }
EXPORT_SYMBOL(…);

unsigned int host1x_syncpt_nb_pts(struct host1x *host)
{ … }

unsigned int host1x_syncpt_nb_bases(struct host1x *host)
{ … }

unsigned int host1x_syncpt_nb_mlocks(struct host1x *host)
{ … }

/**
 * host1x_syncpt_get_by_id() - obtain a syncpoint by ID
 * @host: host1x controller
 * @id: syncpoint ID
 */
struct host1x_syncpt *host1x_syncpt_get_by_id(struct host1x *host,
					      unsigned int id)
{ … }
EXPORT_SYMBOL(…);

/**
 * host1x_syncpt_get_by_id_noref() - obtain a syncpoint by ID but don't
 * 	increase the refcount.
 * @host: host1x controller
 * @id: syncpoint ID
 */
struct host1x_syncpt *host1x_syncpt_get_by_id_noref(struct host1x *host,
						    unsigned int id)
{ … }
EXPORT_SYMBOL(…);

/**
 * host1x_syncpt_get() - increment syncpoint refcount
 * @sp: syncpoint
 */
struct host1x_syncpt *host1x_syncpt_get(struct host1x_syncpt *sp)
{ … }
EXPORT_SYMBOL(…);

/**
 * host1x_syncpt_get_base() - obtain the wait base associated with a syncpoint
 * @sp: host1x syncpoint
 */
struct host1x_syncpt_base *host1x_syncpt_get_base(struct host1x_syncpt *sp)
{ … }
EXPORT_SYMBOL(…);

/**
 * host1x_syncpt_base_id() - retrieve the ID of a syncpoint wait base
 * @base: host1x syncpoint wait base
 */
u32 host1x_syncpt_base_id(struct host1x_syncpt_base *base)
{ … }
EXPORT_SYMBOL(…);

static void do_nothing(struct kref *ref)
{ … }

/**
 * host1x_syncpt_release_vblank_reservation() - Make VBLANK syncpoint
 *   available for allocation
 *
 * @client: host1x bus client
 * @syncpt_id: syncpoint ID to make available
 *
 * Makes VBLANK<i> syncpoint available for allocatation if it was
 * reserved at initialization time. This should be called by the display
 * driver after it has ensured that any VBLANK increment programming configured
 * by the boot chain has been disabled.
 */
void host1x_syncpt_release_vblank_reservation(struct host1x_client *client,
					      u32 syncpt_id)
{ … }
EXPORT_SYMBOL(…);