/**************************************************************************
 *
 * Copyright © 2009-2011 VMware, Inc., Palo Alto, CA., 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.
 *
 **************************************************************************/
#define mb()    asm volatile("mfence" : : : "memory")
#define rmb()   asm volatile("lfence" : : : "memory")
#define wmb()   asm volatile("sfence" : : : "memory")

#include <drm/drmP.h>
#include <drm/ttm/ttm_bo_driver.h>
#include "vmwgfx_drv.h"


#define VMW_PPN_SIZE sizeof(unsigned long)

static int vmw_gmr2_bind(struct vmw_private *dev_priv,
			 struct page *pages[],
			 unsigned long num_pages,
			 int gmr_id)
{
	SVGAFifoCmdDefineGMR2 define_cmd;
	SVGAFifoCmdRemapGMR2 remap_cmd;
	uint32_t define_size = sizeof(define_cmd) + 4;
	uint32_t remap_size = VMW_PPN_SIZE * num_pages + sizeof(remap_cmd) + 4;
	uint32_t *cmd;
	uint32_t *cmd_orig;
	uint32_t i;

	cmd_orig = cmd = vmw_fifo_reserve(dev_priv, define_size + remap_size);
	if (unlikely(cmd == NULL))
		return -ENOMEM;

	define_cmd.gmrId = gmr_id;
	define_cmd.numPages = num_pages;

	remap_cmd.gmrId = gmr_id;
	remap_cmd.flags = (VMW_PPN_SIZE > sizeof(*cmd)) ?
		SVGA_REMAP_GMR2_PPN64 : SVGA_REMAP_GMR2_PPN32;
	remap_cmd.offsetPages = 0;
	remap_cmd.numPages = num_pages;

	*cmd++ = SVGA_CMD_DEFINE_GMR2;
	memcpy(cmd, &define_cmd, sizeof(define_cmd));
	cmd += sizeof(define_cmd) / sizeof(uint32);

	*cmd++ = SVGA_CMD_REMAP_GMR2;
	memcpy(cmd, &remap_cmd, sizeof(remap_cmd));
	cmd += sizeof(remap_cmd) / sizeof(uint32);

	for (i = 0; i < num_pages; ++i) {
		if (VMW_PPN_SIZE <= 4)
			*cmd = page_to_pfn(*pages++);
		else
			*((uint64_t *)cmd) = page_to_pfn(*pages++);

		cmd += VMW_PPN_SIZE / sizeof(*cmd);
	}

	vmw_fifo_commit(dev_priv, define_size + remap_size);

	return 0;
}

static void vmw_gmr2_unbind(struct vmw_private *dev_priv,
			    int gmr_id)
{
	SVGAFifoCmdDefineGMR2 define_cmd;
	uint32_t define_size = sizeof(define_cmd) + 4;
	uint32_t *cmd;

	cmd = vmw_fifo_reserve(dev_priv, define_size);
	if (unlikely(cmd == NULL)) {
		DRM_ERROR("GMR2 unbind failed.\n");
		return;
	}
	define_cmd.gmrId = gmr_id;
	define_cmd.numPages = 0;

	*cmd++ = SVGA_CMD_DEFINE_GMR2;
	memcpy(cmd, &define_cmd, sizeof(define_cmd));

	vmw_fifo_commit(dev_priv, define_size);
}


int vmw_gmr_bind(struct vmw_private *dev_priv,
		 struct page *pages[],
		 unsigned long num_pages,
		 int gmr_id)
{
	struct list_head desc_pages;
	int ret;

	if (likely(dev_priv->capabilities & SVGA_CAP_GMR2))
		return vmw_gmr2_bind(dev_priv, pages, num_pages, gmr_id);

    printf("%s epic fail\n",__FUNCTION__);
    return -EINVAL;
}


void vmw_gmr_unbind(struct vmw_private *dev_priv, int gmr_id)
{
	if (likely(dev_priv->capabilities & SVGA_CAP_GMR2)) {
		vmw_gmr2_unbind(dev_priv, gmr_id);
		return;
	}

	mutex_lock(&dev_priv->hw_mutex);
	vmw_write(dev_priv, SVGA_REG_GMR_ID, gmr_id);
	wmb();
	vmw_write(dev_priv, SVGA_REG_GMR_DESCRIPTOR, 0);
	mb();
	mutex_unlock(&dev_priv->hw_mutex);
}