/**************************************************************************
 * 
 * Copyright 2006 Tungsten Graphics, Inc., Cedar Park, Texas.
 * 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 TUNGSTEN GRAPHICS 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.
 * 
 **************************************************************************/

/* Provide additional functionality on top of bufmgr buffers:
 *   - 2d semantics and blit operations
 *   - refcounting of buffers for multiple images in a buffer.
 *   - refcounting of buffer mappings.
 *   - some logic for moving the buffers to the best memory pools for
 *     given operations.
 *
 * Most of this is to make it easier to implement the fixed-layout
 * mipmap tree required by intel hardware in the face of GL's
 * programming interface where each image can be specifed in random
 * order and it isn't clear what layout the tree should have until the
 * last moment.
 */

#include "intel_context.h"
#include "intel_regions.h"
#include "intel_blit.h"
#include "intel_buffer_objects.h"
#include "dri_bufmgr.h"
#include "intel_bufmgr_ttm.h"
#include "intel_batchbuffer.h"

#define FILE_DEBUG_FLAG DEBUG_REGION

/* XXX: Thread safety?
 */
GLubyte *
intel_region_map(struct intel_context *intel, struct intel_region *region)
{
   DBG("%s\n", __FUNCTION__);
   if (!region->map_refcount++) {
      if (region->pbo)
         intel_region_cow(intel, region);

      dri_bo_map(region->buffer, GL_TRUE);
      region->map = region->buffer->virtual;
   }

   return region->map;
}

void
intel_region_unmap(struct intel_context *intel, struct intel_region *region)
{
   DBG("%s\n", __FUNCTION__);
   if (!--region->map_refcount) {
      dri_bo_unmap(region->buffer);
      region->map = NULL;
   }
}

static struct intel_region *
intel_region_alloc_internal(struct intel_context *intel,
			    GLuint cpp, GLuint pitch, GLuint height,
			    GLuint tiled, dri_bo *buffer)
{
   struct intel_region *region;

   DBG("%s\n", __FUNCTION__);

   if (buffer == NULL)
      return NULL;

   region = calloc(sizeof(*region), 1);
   region->cpp = cpp;
   region->pitch = pitch;
   region->height = height;     /* needed? */
   region->refcount = 1;
   region->tiled = tiled;
   region->buffer = buffer;

   return region;
}

struct intel_region *
intel_region_alloc(struct intel_context *intel,
                   GLuint cpp, GLuint pitch, GLuint height)
{
   dri_bo *buffer;

   buffer = dri_bo_alloc(intel->bufmgr, "region",
			 pitch * cpp * height, 64,
			 DRM_BO_FLAG_MEM_LOCAL |
			 DRM_BO_FLAG_CACHED |
			 DRM_BO_FLAG_CACHED_MAPPED);

   return intel_region_alloc_internal(intel, cpp, pitch, height, 0, buffer);
}

struct intel_region *
intel_region_alloc_for_handle(struct intel_context *intel,
			      GLuint cpp, GLuint pitch, GLuint height,
			      GLuint tiled, GLuint handle)
{
   dri_bo *buffer;

   buffer = intel_ttm_bo_create_from_handle(intel->bufmgr, "region", handle);

   return intel_region_alloc_internal(intel,
				      cpp, pitch, height, tiled, buffer);
}

void
intel_region_reference(struct intel_region **dst, struct intel_region *src)
{
   assert(*dst == NULL);
   if (src) {
      src->refcount++;
      *dst = src;
   }
}

void
intel_region_release(struct intel_region **region)
{
   if (!*region)
      return;

   DBG("%s %d\n", __FUNCTION__, (*region)->refcount - 1);

   ASSERT((*region)->refcount > 0);
   (*region)->refcount--;

   if ((*region)->refcount == 0) {
      assert((*region)->map_refcount == 0);

      if ((*region)->pbo)
	 (*region)->pbo->region = NULL;
      (*region)->pbo = NULL;
      dri_bo_unreference((*region)->buffer);
      free(*region);
   }
   *region = NULL;
}

/*
 * XXX Move this into core Mesa?
 */
void
_mesa_copy_rect(GLubyte * dst,
                GLuint cpp,
                GLuint dst_pitch,
                GLuint dst_x,
                GLuint dst_y,
                GLuint width,
                GLuint height,
                const GLubyte * src,
                GLuint src_pitch, GLuint src_x, GLuint src_y)
{
   GLuint i;

   dst_pitch *= cpp;
   src_pitch *= cpp;
   dst += dst_x * cpp;
   src += src_x * cpp;
   dst += dst_y * dst_pitch;
   src += src_y * dst_pitch;
   width *= cpp;

   if (width == dst_pitch && width == src_pitch)
      memcpy(dst, src, height * width);
   else {
      for (i = 0; i < height; i++) {
         memcpy(dst, src, width);
         dst += dst_pitch;
         src += src_pitch;
      }
   }
}


/* Upload data to a rectangular sub-region.  Lots of choices how to do this:
 *
 * - memcpy by span to current destination
 * - upload data as new buffer and blit
 *
 * Currently always memcpy.
 */
void
intel_region_data(struct intel_context *intel,
                  struct intel_region *dst,
                  GLuint dst_offset,
                  GLuint dstx, GLuint dsty,
                  const void *src, GLuint src_pitch,
                  GLuint srcx, GLuint srcy, GLuint width, GLuint height)
{
   GLboolean locked = GL_FALSE;

   DBG("%s\n", __FUNCTION__);

   if (intel == NULL)
      return;

   if (dst->pbo) {
      if (dstx == 0 &&
          dsty == 0 && width == dst->pitch && height == dst->height)
         intel_region_release_pbo(intel, dst);
      else
         intel_region_cow(intel, dst);
   }

   if (!intel->locked) {
      LOCK_HARDWARE(intel);
      locked = GL_TRUE;
   }

   _mesa_copy_rect(intel_region_map(intel, dst) + dst_offset,
                   dst->cpp,
                   dst->pitch,
                   dstx, dsty, width, height, src, src_pitch, srcx, srcy);

   intel_region_unmap(intel, dst);

   if (locked)
      UNLOCK_HARDWARE(intel);

}

/* Copy rectangular sub-regions. Need better logic about when to
 * push buffers into AGP - will currently do so whenever possible.
 */
void
intel_region_copy(struct intel_context *intel,
                  struct intel_region *dst,
                  GLuint dst_offset,
                  GLuint dstx, GLuint dsty,
                  struct intel_region *src,
                  GLuint src_offset,
                  GLuint srcx, GLuint srcy, GLuint width, GLuint height)
{
   DBG("%s\n", __FUNCTION__);

   if (intel == NULL)
      return;

   if (dst->pbo) {
      if (dstx == 0 &&
          dsty == 0 && width == dst->pitch && height == dst->height)
         intel_region_release_pbo(intel, dst);
      else
         intel_region_cow(intel, dst);
   }

   assert(src->cpp == dst->cpp);

   intelEmitCopyBlit(intel,
                     dst->cpp,
                     src->pitch, src->buffer, src_offset, src->tiled,
                     dst->pitch, dst->buffer, dst_offset, dst->tiled,
                     srcx, srcy, dstx, dsty, width, height,
		     GL_COPY);
}

/* Fill a rectangular sub-region.  Need better logic about when to
 * push buffers into AGP - will currently do so whenever possible.
 */
void
intel_region_fill(struct intel_context *intel,
                  struct intel_region *dst,
                  GLuint dst_offset,
                  GLuint dstx, GLuint dsty,
                  GLuint width, GLuint height, GLuint color)
{
   DBG("%s\n", __FUNCTION__);

   if (intel == NULL)
      return;   

   if (dst->pbo) {
      if (dstx == 0 &&
          dsty == 0 && width == dst->pitch && height == dst->height)
         intel_region_release_pbo(intel, dst);
      else
         intel_region_cow(intel, dst);
   }

   intelEmitFillBlit(intel,
                     dst->cpp,
                     dst->pitch, dst->buffer, dst_offset, dst->tiled,
                     dstx, dsty, width, height, color);
}

/* Attach to a pbo, discarding our data.  Effectively zero-copy upload
 * the pbo's data.
 */
void
intel_region_attach_pbo(struct intel_context *intel,
                        struct intel_region *region,
                        struct intel_buffer_object *pbo)
{
   if (region->pbo == pbo)
      return;

   /* If there is already a pbo attached, break the cow tie now.
    * Don't call intel_region_release_pbo() as that would
    * unnecessarily allocate a new buffer we would have to immediately
    * discard.
    */
   if (region->pbo) {
      region->pbo->region = NULL;
      region->pbo = NULL;
   }

   if (region->buffer) {
      dri_bo_unreference(region->buffer);
      region->buffer = NULL;
   }

   region->pbo = pbo;
   region->pbo->region = region;
   dri_bo_reference(pbo->buffer);
   region->buffer = pbo->buffer;
}


/* Break the COW tie to the pbo and allocate a new buffer.
 * The pbo gets to keep the data.
 */
void
intel_region_release_pbo(struct intel_context *intel,
                         struct intel_region *region)
{
   assert(region->buffer == region->pbo->buffer);
   region->pbo->region = NULL;
   region->pbo = NULL;
   dri_bo_unreference(region->buffer);
   region->buffer = NULL;

   region->buffer = dri_bo_alloc(intel->bufmgr, "region",
				 region->pitch * region->cpp * region->height,
				 64,
				 DRM_BO_FLAG_MEM_LOCAL |
				 DRM_BO_FLAG_CACHED |
				 DRM_BO_FLAG_CACHED_MAPPED);
}

/* Break the COW tie to the pbo.  Both the pbo and the region end up
 * with a copy of the data.
 */
void
intel_region_cow(struct intel_context *intel, struct intel_region *region)
{
   struct intel_buffer_object *pbo = region->pbo;
   GLboolean was_locked = intel->locked;

   if (intel == NULL)
      return;

   intel_region_release_pbo(intel, region);

   assert(region->cpp * region->pitch * region->height == pbo->Base.Size);

   DBG("%s (%d bytes)\n", __FUNCTION__, pbo->Base.Size);

   /* Now blit from the texture buffer to the new buffer: 
    */

   intel_batchbuffer_flush(intel->batch);

   was_locked = intel->locked;
   if (intel->locked)
      LOCK_HARDWARE(intel);

   intelEmitCopyBlit(intel,
		     region->cpp,
		     region->pitch, region->buffer, 0, region->tiled,
		     region->pitch, pbo->buffer, 0, region->tiled,
		     0, 0, 0, 0,
		     region->pitch, region->height,
		     GL_COPY);

   intel_batchbuffer_flush(intel->batch);

   if (was_locked)
      UNLOCK_HARDWARE(intel);
}

dri_bo *
intel_region_buffer(struct intel_context *intel,
                    struct intel_region *region, GLuint flag)
{
   if (region->pbo) {
      if (flag == INTEL_WRITE_PART)
         intel_region_cow(intel, region);
      else if (flag == INTEL_WRITE_FULL)
         intel_region_release_pbo(intel, region);
   }

   return region->buffer;
}

static struct intel_region *
intel_recreate_static(struct intel_context *intel,
		      const char *name,
		      struct intel_region *region,
		      intelRegion *region_desc)
{
   intelScreenPrivate *intelScreen = intel->intelScreen;

   if (region == NULL) {
      region = calloc(sizeof(*region), 1);
      region->refcount = 1;
   }

   if (intel->ctx.Visual.rgbBits == 24)
      region->cpp = 4;
   else
      region->cpp = intel->ctx.Visual.rgbBits / 8;
   region->pitch = intelScreen->pitch;
   region->height = intelScreen->height;     /* needed? */
   region->tiled = region_desc->tiled;

   if (intel->ttm) {
      assert(region_desc->bo_handle != -1);
      region->buffer = intel_ttm_bo_create_from_handle(intel->bufmgr,
						       name,
						       region_desc->bo_handle);
   } else {
      region->buffer = dri_bo_alloc_static(intel->bufmgr,
					   name,
					   region_desc->offset,
					   intelScreen->pitch *
					   intelScreen->height,
					   region_desc->map,
					   DRM_BO_FLAG_MEM_TT);
   }

   assert(region->buffer != NULL);

   return region;
}

/**
 * Create intel_region structs to describe the static front, back, and depth
 * buffers created by the xserver.
 *
 * Although FBO's mean we now no longer use these as render targets in
 * all circumstances, they won't go away until the back and depth
 * buffers become private, and the front buffer will remain even then.
 *
 * Note that these don't allocate video memory, just describe
 * allocations alread made by the X server.
 */
void
intel_recreate_static_regions(struct intel_context *intel)
{
   intelScreenPrivate *intelScreen = intel->intelScreen;

   intel->front_region =
      intel_recreate_static(intel, "front",
			    intel->front_region,
			    &intelScreen->front);

   intel->back_region =
      intel_recreate_static(intel, "back",
			    intel->back_region,
			    &intelScreen->back);

#ifdef I915
   if (intelScreen->third.handle) {
      intel->third_region =
	 intel_recreate_static(intel, "third",
			       intel->third_region,
			       &intelScreen->third);
   }
#endif /* I915 */

   /* Still assumes front.cpp == depth.cpp.  We can kill this when we move to
    * private buffers.
    */
   intel->depth_region =
      intel_recreate_static(intel, "depth",
			    intel->depth_region,
			    &intelScreen->depth);
}