xref: /src/sys/external/bsd/drm2/drm/drm_module.c

/*	$NetBSD: drm_module.c,v 1.12 2018/08/27 15:31:27 riastradh Exp $	*/

/*-
 * Copyright (c) 2013 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Taylor R. Campbell.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: drm_module.c,v 1.12 2018/08/27 15:31:27 riastradh Exp $");

#include <sys/types.h>
#include <sys/condvar.h>
#include <sys/conf.h>
#include <sys/device.h>
#include <sys/module.h>
#include <sys/mutex.h>
#ifndef _MODULE
#include <sys/once.h>
#endif
#include <sys/reboot.h>
#include <sys/systm.h>

#include <linux/mutex.h>

#include <drm/drmP.h>
#include <drm/drm_encoder_slave.h>
#include <drm/drm_internal.h>
#include <drm/drm_sysctl.h>

/*
 * XXX I2C stuff should be moved to a separate drmkms_i2c module.
 */
MODULE(MODULE_CLASS_DRIVER, drmkms, "drmkms_linux");

struct mutex	drm_global_mutex;

struct drm_sysctl_def drm_def = DRM_SYSCTL_INIT();

static struct {
	kmutex_t		lock;
	kcondvar_t		cv;
	unsigned		refcnt;
	int			(*hook)(struct drm_device *,
				    struct drm_master *, struct drm_unique *);
} set_unique_hook __cacheline_aligned;

static int
drm_init(void)
{
	extern int linux_guarantee_initialized(void);
	int error;

	error = linux_guarantee_initialized();
	if (error)
		return error;

	if (ISSET(boothowto, AB_DEBUG))
		drm_debug = ~(unsigned int)0;

	spin_lock_init(&drm_minor_lock);
	idr_init(&drm_minors_idr);
	linux_mutex_init(&drm_global_mutex);
	drm_connector_ida_init();
	drm_global_init();
	drm_sysctl_init(&drm_def);
	drm_i2c_encoders_init();

	return 0;
}

int	drm_guarantee_initialized(void); /* XXX */
int
drm_guarantee_initialized(void)
{
#ifdef _MODULE
	return 0;
#else
	static ONCE_DECL(drm_init_once);

	return RUN_ONCE(&drm_init_once, &drm_init);
#endif
}

static void
drm_fini(void)
{

	drm_i2c_encoders_fini();
	drm_sysctl_fini(&drm_def);
	drm_global_release();
	drm_connector_ida_destroy();
	linux_mutex_destroy(&drm_global_mutex);
	idr_destroy(&drm_minors_idr);
	spin_lock_destroy(&drm_minor_lock);
}

int
drm_irq_by_busid(struct drm_device *dev, void *data, struct drm_file *file)
{

	return -ENODEV;
}

/* XXX Stupid kludge...  */

void
drm_pci_set_unique_hook(int (**hook)(struct drm_device *, struct drm_master *,
	struct drm_unique *))
{
	int (*old)(struct drm_device *, struct drm_master *,
	    struct drm_unique *);

	mutex_enter(&set_unique_hook.lock);
	while (set_unique_hook.refcnt)
		cv_wait(&set_unique_hook.cv, &set_unique_hook.lock);
	old = set_unique_hook.hook;
	set_unique_hook.hook = *hook;
	*hook = old;
	mutex_exit(&set_unique_hook.lock);
}

int
drm_pci_set_unique(struct drm_device *dev, struct drm_master *master,
    struct drm_unique *unique)
{
	int ret;

	mutex_enter(&set_unique_hook.lock);
	while (set_unique_hook.refcnt == UINT_MAX)
		cv_wait(&set_unique_hook.cv, &set_unique_hook.lock);
	set_unique_hook.refcnt++;
	mutex_exit(&set_unique_hook.lock);

	if (set_unique_hook.hook)
		ret = set_unique_hook.hook(dev, master, unique);
	else
		ret = -ENODEV;

	mutex_enter(&set_unique_hook.lock);
	if (set_unique_hook.refcnt-- == UINT_MAX ||
	    set_unique_hook.refcnt == 0)
		cv_broadcast(&set_unique_hook.cv);
	mutex_exit(&set_unique_hook.lock);

	return ret;
}

static int
drmkms_modcmd(modcmd_t cmd, void *arg __unused)
{
#ifdef _MODULE
	devmajor_t bmajor = NODEVMAJOR, cmajor = NODEVMAJOR;
#endif
	int error;

	switch (cmd) {
	case MODULE_CMD_INIT:
#ifdef _MODULE
		error = drm_init();
#else
		error = drm_guarantee_initialized();
#endif
		if (error)
			return error;
#ifdef _MODULE
		error = devsw_attach("drm", NULL, &bmajor,
		    &drm_cdevsw, &cmajor);
		if (error) {
			aprint_error("drmkms: unable to attach devsw: %d\n",
			    error);
			return error;
		}
#endif
		return 0;

	case MODULE_CMD_FINI:
#ifdef _MODULE
		error = devsw_detach(NULL, &drm_cdevsw);
		if (error)
			return error;
#endif
		drm_fini();
		return 0;

	default:
		return ENOTTY;
	}
}