/*	$NetBSD: sis_mm.c,v 1.4 2021/12/18 23:45:44 riastradh Exp $	*/

/**************************************************************************
 *
 * Copyright 2006 Tungsten Graphics, Inc., Bismarck, ND., USA.
 * All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sub license, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice (including the
 * next paragraph) shall be included in all copies or substantial portions
 * of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 * USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 *
 **************************************************************************/

/*
 * Authors:
 *    Thomas Hellström <thomas-at-tungstengraphics-dot-com>
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: sis_mm.c,v 1.4 2021/12/18 23:45:44 riastradh Exp $");

#include <video/sisfb.h>

#include <drm/drm_device.h>
#include <drm/drm_file.h>
#include <drm/sis_drm.h>

#include "sis_drv.h"


#define VIDEO_TYPE 0
#define AGP_TYPE 1


struct sis_memblock {
	struct drm_mm_node mm_node;
	struct sis_memreq req;
	struct list_head owner_list;
};

#if defined(CONFIG_FB_SIS) || defined(CONFIG_FB_SIS_MODULE)
/* fb management via fb device */

#define SIS_MM_ALIGN_SHIFT 0
#define SIS_MM_ALIGN_MASK 0

#else /* CONFIG_FB_SIS[_MODULE] */

#define SIS_MM_ALIGN_SHIFT 4
#define SIS_MM_ALIGN_MASK ((1 << SIS_MM_ALIGN_SHIFT) - 1)

#endif /* CONFIG_FB_SIS[_MODULE] */

static int sis_fb_init(struct drm_device *dev, void *data, struct drm_file *file_priv)
{
	drm_sis_private_t *dev_priv = dev->dev_private;
	drm_sis_fb_t *fb = data;

	mutex_lock(&dev->struct_mutex);
	/* Unconditionally init the drm_mm, even though we don't use it when the
	 * fb sis driver is available - make cleanup easier. */
	drm_mm_init(&dev_priv->vram_mm, 0, fb->size >> SIS_MM_ALIGN_SHIFT);

	dev_priv->vram_initialized = 1;
	dev_priv->vram_offset = fb->offset;

	mutex_unlock(&dev->struct_mutex);
	DRM_DEBUG("offset = %lu, size = %lu\n", fb->offset, fb->size);

	return 0;
}

static int sis_drm_alloc(struct drm_device *dev, struct drm_file *file,
			 void *data, int pool)
{
	drm_sis_private_t *dev_priv = dev->dev_private;
	drm_sis_mem_t *mem = data;
	int retval = 0, user_key;
	struct sis_memblock *item;
	struct sis_file_private *file_priv = file->driver_priv;
	unsigned long offset;

	idr_preload(GFP_KERNEL);
	mutex_lock(&dev->struct_mutex);

	if (0 == ((pool == 0) ? dev_priv->vram_initialized :
		      dev_priv->agp_initialized)) {
		DRM_ERROR
		    ("Attempt to allocate from uninitialized memory manager.\n");
		mutex_unlock(&dev->struct_mutex);
		idr_preload_end();
		return -EINVAL;
	}

	item = kzalloc(sizeof(*item), GFP_KERNEL);
	if (!item) {
		retval = -ENOMEM;
		goto fail_alloc;
	}

	mem->size = (mem->size + SIS_MM_ALIGN_MASK) >> SIS_MM_ALIGN_SHIFT;
	if (pool == AGP_TYPE) {
		retval = drm_mm_insert_node(&dev_priv->agp_mm,
					    &item->mm_node,
					    mem->size);
		offset = item->mm_node.start;
	} else {
#if defined(CONFIG_FB_SIS) || defined(CONFIG_FB_SIS_MODULE)
		item->req.size = mem->size;
		sis_malloc(&item->req);
		if (item->req.size == 0)
			retval = -ENOMEM;
		offset = item->req.offset;
#else
		retval = drm_mm_insert_node(&dev_priv->vram_mm,
					    &item->mm_node,
					    mem->size);
		offset = item->mm_node.start;
#endif
	}
	if (retval)
		goto fail_alloc;

	retval = idr_alloc(&dev_priv->object_idr, item, 1, 0, GFP_KERNEL);
	if (retval < 0)
		goto fail_idr;
	user_key = retval;

	list_add(&item->owner_list, &file_priv->obj_list);
	mutex_unlock(&dev->struct_mutex);
	idr_preload_end();

	mem->offset = ((pool == 0) ?
		      dev_priv->vram_offset : dev_priv->agp_offset) +
	    (offset << SIS_MM_ALIGN_SHIFT);
	mem->free = user_key;
	mem->size = mem->size << SIS_MM_ALIGN_SHIFT;

	return 0;

fail_idr:
	drm_mm_remove_node(&item->mm_node);
fail_alloc:
	kfree(item);
	mutex_unlock(&dev->struct_mutex);
	idr_preload_end();

	mem->offset = 0;
	mem->size = 0;
	mem->free = 0;

	DRM_DEBUG("alloc %d, size = %ld, offset = %ld\n", pool, mem->size,
		  mem->offset);

	return retval;
}

static int sis_drm_free(struct drm_device *dev, void *data, struct drm_file *file_priv)
{
	drm_sis_private_t *dev_priv = dev->dev_private;
	drm_sis_mem_t *mem = data;
	struct sis_memblock *obj;

	mutex_lock(&dev->struct_mutex);
	obj = idr_find(&dev_priv->object_idr, mem->free);
	if (obj == NULL) {
		mutex_unlock(&dev->struct_mutex);
		return -EINVAL;
	}

	idr_remove(&dev_priv->object_idr, mem->free);
	list_del(&obj->owner_list);
	if (drm_mm_node_allocated(&obj->mm_node))
		drm_mm_remove_node(&obj->mm_node);
#if defined(CONFIG_FB_SIS) || defined(CONFIG_FB_SIS_MODULE)
	else
		sis_free(obj->req.offset);
#endif
	kfree(obj);
	mutex_unlock(&dev->struct_mutex);
	DRM_DEBUG("free = 0x%lx\n", mem->free);

	return 0;
}

static int sis_fb_alloc(struct drm_device *dev, void *data,
			struct drm_file *file_priv)
{
	return sis_drm_alloc(dev, file_priv, data, VIDEO_TYPE);
}

static int sis_ioctl_agp_init(struct drm_device *dev, void *data,
			      struct drm_file *file_priv)
{
	drm_sis_private_t *dev_priv = dev->dev_private;
	drm_sis_agp_t *agp = data;
	dev_priv = dev->dev_private;

	mutex_lock(&dev->struct_mutex);
	drm_mm_init(&dev_priv->agp_mm, 0, agp->size >> SIS_MM_ALIGN_SHIFT);

	dev_priv->agp_initialized = 1;
	dev_priv->agp_offset = agp->offset;
	mutex_unlock(&dev->struct_mutex);

	DRM_DEBUG("offset = %lu, size = %lu\n", agp->offset, agp->size);
	return 0;
}

static int sis_ioctl_agp_alloc(struct drm_device *dev, void *data,
			       struct drm_file *file_priv)
{

	return sis_drm_alloc(dev, file_priv, data, AGP_TYPE);
}

static drm_local_map_t *sis_reg_init(struct drm_device *dev)
{
	struct drm_map_list *entry;
	drm_local_map_t *map;

	list_for_each_entry(entry, &dev->maplist, head) {
		map = entry->map;
		if (!map)
			continue;
		if (map->type == _DRM_REGISTERS)
			return map;
	}
	return NULL;
}

int sis_idle(struct drm_device *dev)
{
	drm_sis_private_t *dev_priv = dev->dev_private;
	uint32_t idle_reg;
	unsigned long end;
	int i;

	if (dev_priv->idle_fault)
		return 0;

	if (dev_priv->mmio == NULL) {
		dev_priv->mmio = sis_reg_init(dev);
		if (dev_priv->mmio == NULL) {
			DRM_ERROR("Could not find register map.\n");
			return 0;
		}
	}

	/*
	 * Implement a device switch here if needed
	 */

	if (dev_priv->chipset != SIS_CHIP_315)
		return 0;

	/*
	 * Timeout after 3 seconds. We cannot use DRM_WAIT_ON here
	 * because its polling frequency is too low.
	 */

	end = jiffies + (HZ * 3);

	for (i = 0; i < 4; ++i) {
		do {
			idle_reg = SIS_READ(0x85cc);
		} while (!time_after_eq(jiffies, end) &&
			  ((idle_reg & 0x80000000) != 0x80000000));
	}

	if (time_after_eq(jiffies, end)) {
		DRM_ERROR("Graphics engine idle timeout. "
			  "Disabling idle check\n");
		dev_priv->idle_fault = 1;
	}

	/*
	 * The caller never sees an error code. It gets trapped
	 * in libdrm.
	 */

	return 0;
}


void sis_lastclose(struct drm_device *dev)
{
	drm_sis_private_t *dev_priv = dev->dev_private;

	if (!dev_priv)
		return;

	mutex_lock(&dev->struct_mutex);
	if (dev_priv->vram_initialized) {
		drm_mm_takedown(&dev_priv->vram_mm);
		dev_priv->vram_initialized = 0;
	}
	if (dev_priv->agp_initialized) {
		drm_mm_takedown(&dev_priv->agp_mm);
		dev_priv->agp_initialized = 0;
	}
	dev_priv->mmio = NULL;
	mutex_unlock(&dev->struct_mutex);
}

void sis_reclaim_buffers_locked(struct drm_device *dev,
				struct drm_file *file)
{
	struct sis_file_private *file_priv = file->driver_priv;
	struct sis_memblock *entry, *next;

	if (!(dev->master && file->master->lock.hw_lock))
		return;

	drm_legacy_idlelock_take(&file->master->lock);

	mutex_lock(&dev->struct_mutex);
	if (list_empty(&file_priv->obj_list)) {
		mutex_unlock(&dev->struct_mutex);
		drm_legacy_idlelock_release(&file->master->lock);

		return;
	}

	sis_idle(dev);


	list_for_each_entry_safe(entry, next, &file_priv->obj_list,
				 owner_list) {
		list_del(&entry->owner_list);
		if (drm_mm_node_allocated(&entry->mm_node))
			drm_mm_remove_node(&entry->mm_node);
#if defined(CONFIG_FB_SIS) || defined(CONFIG_FB_SIS_MODULE)
		else
			sis_free(entry->req.offset);
#endif
		kfree(entry);
	}
	mutex_unlock(&dev->struct_mutex);

	drm_legacy_idlelock_release(&file->master->lock);

	return;
}

const struct drm_ioctl_desc sis_ioctls[] = {
	DRM_IOCTL_DEF_DRV(SIS_FB_ALLOC, sis_fb_alloc, DRM_AUTH),
	DRM_IOCTL_DEF_DRV(SIS_FB_FREE, sis_drm_free, DRM_AUTH),
	DRM_IOCTL_DEF_DRV(SIS_AGP_INIT, sis_ioctl_agp_init, DRM_AUTH | DRM_MASTER | DRM_ROOT_ONLY),
	DRM_IOCTL_DEF_DRV(SIS_AGP_ALLOC, sis_ioctl_agp_alloc, DRM_AUTH),
	DRM_IOCTL_DEF_DRV(SIS_AGP_FREE, sis_drm_free, DRM_AUTH),
	DRM_IOCTL_DEF_DRV(SIS_FB_INIT, sis_fb_init, DRM_AUTH | DRM_MASTER | DRM_ROOT_ONLY),
};

int sis_max_ioctl = ARRAY_SIZE(sis_ioctls);