/**************************************************************************
 * Copyright (c) 2007, Intel Corporation.
 * All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Intel funded Tungsten Graphics (http://www.tungstengraphics.com) to
 * develop this driver.
 *
 **************************************************************************/

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/tty.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/fb.h>
#include <linux/init.h>
#include <linux/console.h>

#include <drm/drmP.h>
#include <drm/drm.h>
#include <drm/drm_crtc.h>

#include "psb_drv.h"
#include "psb_reg.h"
#include "psb_drv.h"
#include "psb_fb.h"

void psb_spank(struct drm_psb_private *dev_priv)
{
        PSB_WSGX32(_PSB_CS_RESET_BIF_RESET | _PSB_CS_RESET_DPM_RESET |
		_PSB_CS_RESET_TA_RESET | _PSB_CS_RESET_USE_RESET |
		_PSB_CS_RESET_ISP_RESET | _PSB_CS_RESET_TSP_RESET |
		_PSB_CS_RESET_TWOD_RESET, PSB_CR_SOFT_RESET);
	(void) PSB_RSGX32(PSB_CR_SOFT_RESET);

	msleep(1);

	PSB_WSGX32(0, PSB_CR_SOFT_RESET);
	wmb();
	PSB_WSGX32(PSB_RSGX32(PSB_CR_BIF_CTRL) | _PSB_CB_CTRL_CLEAR_FAULT,
		   PSB_CR_BIF_CTRL);
	wmb();
	(void) PSB_RSGX32(PSB_CR_BIF_CTRL);

	msleep(1);
	PSB_WSGX32(PSB_RSGX32(PSB_CR_BIF_CTRL) & ~_PSB_CB_CTRL_CLEAR_FAULT,
		   PSB_CR_BIF_CTRL);
	(void) PSB_RSGX32(PSB_CR_BIF_CTRL);
	PSB_WSGX32(dev_priv->pg->gatt_start, PSB_CR_BIF_TWOD_REQ_BASE);
}

static int psb_2d_wait_available(struct drm_psb_private *dev_priv,
			  unsigned size)
{
	uint32_t avail = PSB_RSGX32(PSB_CR_2D_SOCIF);
	unsigned long t = jiffies + HZ;

	while(avail < size) {
		avail = PSB_RSGX32(PSB_CR_2D_SOCIF);
		if (time_after(jiffies, t)) {
			psb_spank(dev_priv);
			return -EIO;
		}
	}
	return 0;
}

/* FIXME: Remember if we expose the 2D engine to the DRM we need to serialize
   it with console use */

int psbfb_2d_submit(struct drm_psb_private *dev_priv, uint32_t *cmdbuf,
	 	  	   unsigned size)
{
	int ret = 0;
	int i;
	unsigned submit_size;

	while (size > 0) {
		submit_size = (size < 0x60) ? size : 0x60;
		size -= submit_size;
		ret = psb_2d_wait_available(dev_priv, submit_size);
		if (ret)
			return ret;

		submit_size <<= 2;
		for (i = 0; i < submit_size; i += 4) {
			PSB_WSGX32(*cmdbuf++, PSB_SGX_2D_SLAVE_PORT + i);
		}
		(void)PSB_RSGX32(PSB_SGX_2D_SLAVE_PORT + i - 4);
	}
	return 0;
}

static int psb_accel_2d_fillrect(struct drm_psb_private *dev_priv,
				 uint32_t dst_offset, uint32_t dst_stride,
				 uint32_t dst_format, uint16_t dst_x,
				 uint16_t dst_y, uint16_t size_x,
				 uint16_t size_y, uint32_t fill)
{
	uint32_t buffer[10];
	uint32_t *buf;

	buf = buffer;

	*buf++ = PSB_2D_FENCE_BH;

	*buf++ =
	    PSB_2D_DST_SURF_BH | dst_format | (dst_stride <<
					       PSB_2D_DST_STRIDE_SHIFT);
	*buf++ = dst_offset;

	*buf++ =
	    PSB_2D_BLIT_BH |
	    PSB_2D_ROT_NONE |
	    PSB_2D_COPYORDER_TL2BR |
	    PSB_2D_DSTCK_DISABLE |
	    PSB_2D_SRCCK_DISABLE | PSB_2D_USE_FILL | PSB_2D_ROP3_PATCOPY;

	*buf++ = fill << PSB_2D_FILLCOLOUR_SHIFT;
	*buf++ =
	    (dst_x << PSB_2D_DST_XSTART_SHIFT) | (dst_y <<
						  PSB_2D_DST_YSTART_SHIFT);
	*buf++ =
	    (size_x << PSB_2D_DST_XSIZE_SHIFT) | (size_y <<
						  PSB_2D_DST_YSIZE_SHIFT);
	*buf++ = PSB_2D_FLUSH_BH;

	return psbfb_2d_submit(dev_priv, buffer, buf - buffer);
}

static void psbfb_fillrect_accel(struct fb_info *info,
				 const struct fb_fillrect *r)
{
	struct psb_fbdev *fbdev = info->par;
	struct psb_framebuffer *psbfb = fbdev->pfb;
	struct drm_device *dev = psbfb->base.dev;
	struct drm_framebuffer *fb = fbdev->psb_fb_helper.fb;
	struct drm_psb_private *dev_priv = dev->dev_private;

	uint32_t offset;
	uint32_t stride;
	uint32_t format;

	if (!fb)
		return;

	offset = psbfb->gtt->offset;
	stride = fb->pitch;

	switch (fb->depth) {
	case 8:
		format = PSB_2D_DST_332RGB;
		break;
	case 15:
		format = PSB_2D_DST_555RGB;
		break;
	case 16:
		format = PSB_2D_DST_565RGB;
		break;
	case 24:
	case 32:
		/* this is wrong but since we don't do blending its okay */
		format = PSB_2D_DST_8888ARGB;
		break;
	default:
		/* software fallback */
		cfb_fillrect(info, r);
		return;
	}

	psb_accel_2d_fillrect(dev_priv,
			      offset, stride, format,
			      r->dx, r->dy, r->width, r->height, r->color);
}

void psbfb_fillrect(struct fb_info *info,
			   const struct fb_fillrect *rect)
{
	if (unlikely(info->state != FBINFO_STATE_RUNNING))
		return;

	if (1 || (info->flags & FBINFO_HWACCEL_DISABLED))
		return cfb_fillrect(info, rect);

	/*psb_check_power_state(dev, PSB_DEVICE_SGX); */
	psbfb_fillrect_accel(info, rect);
	/* Drop power again here on MRST FIXMEAC */
}

static u32 psb_accel_2d_copy_direction(int xdir, int ydir)
{
	if (xdir < 0)
		return (ydir < 0) ? PSB_2D_COPYORDER_BR2TL :
                			PSB_2D_COPYORDER_TR2BL;
	else
		return (ydir < 0) ? PSB_2D_COPYORDER_BL2TR :
                			PSB_2D_COPYORDER_TL2BR;
}

/*
 * @src_offset in bytes
 * @src_stride in bytes
 * @src_format psb 2D format defines
 * @dst_offset in bytes
 * @dst_stride in bytes
 * @dst_format psb 2D format defines
 * @src_x offset in pixels
 * @src_y offset in pixels
 * @dst_x offset in pixels
 * @dst_y offset in pixels
 * @size_x of the copied area
 * @size_y of the copied area
 */
static int psb_accel_2d_copy(struct drm_psb_private *dev_priv,
			     uint32_t src_offset, uint32_t src_stride,
			     uint32_t src_format, uint32_t dst_offset,
			     uint32_t dst_stride, uint32_t dst_format,
			     uint16_t src_x, uint16_t src_y,
			     uint16_t dst_x, uint16_t dst_y,
			     uint16_t size_x, uint16_t size_y)
{
	uint32_t blit_cmd;
	uint32_t buffer[10];
	uint32_t *buf;
	uint32_t direction;

	buf = buffer;

	direction =
	    psb_accel_2d_copy_direction(src_x - dst_x, src_y - dst_y);

	if (direction == PSB_2D_COPYORDER_BR2TL ||
	    direction == PSB_2D_COPYORDER_TR2BL) {
		src_x += size_x - 1;
		dst_x += size_x - 1;
	}
	if (direction == PSB_2D_COPYORDER_BR2TL ||
	    direction == PSB_2D_COPYORDER_BL2TR) {
		src_y += size_y - 1;
		dst_y += size_y - 1;
	}

	blit_cmd =
	    PSB_2D_BLIT_BH |
	    PSB_2D_ROT_NONE |
	    PSB_2D_DSTCK_DISABLE |
	    PSB_2D_SRCCK_DISABLE |
	    PSB_2D_USE_PAT | PSB_2D_ROP3_SRCCOPY | direction;

	*buf++ = PSB_2D_FENCE_BH;
	*buf++ =
	    PSB_2D_DST_SURF_BH | dst_format | (dst_stride <<
					       PSB_2D_DST_STRIDE_SHIFT);
	*buf++ = dst_offset;
	*buf++ =
	    PSB_2D_SRC_SURF_BH | src_format | (src_stride <<
					       PSB_2D_SRC_STRIDE_SHIFT);
	*buf++ = src_offset;
	*buf++ =
	    PSB_2D_SRC_OFF_BH | (src_x << PSB_2D_SRCOFF_XSTART_SHIFT) |
	    (src_y << PSB_2D_SRCOFF_YSTART_SHIFT);
	*buf++ = blit_cmd;
	*buf++ =
	    (dst_x << PSB_2D_DST_XSTART_SHIFT) | (dst_y <<
						  PSB_2D_DST_YSTART_SHIFT);
	*buf++ =
	    (size_x << PSB_2D_DST_XSIZE_SHIFT) | (size_y <<
						  PSB_2D_DST_YSIZE_SHIFT);
	*buf++ = PSB_2D_FLUSH_BH;

	return psbfb_2d_submit(dev_priv, buffer, buf - buffer);
}

static void psbfb_copyarea_accel(struct fb_info *info,
				 const struct fb_copyarea *a)
{
	struct psb_fbdev *fbdev = info->par;
	struct psb_framebuffer *psbfb = fbdev->pfb;
	struct drm_device *dev = psbfb->base.dev;
	struct drm_framebuffer *fb = fbdev->psb_fb_helper.fb;
	struct drm_psb_private *dev_priv = dev->dev_private;
	uint32_t offset;
	uint32_t stride;
	uint32_t src_format;
	uint32_t dst_format;

	if (!fb)
		return;

	offset = psbfb->gtt->offset;
	stride = fb->pitch;

	switch (fb->depth) {
	case 8:
		src_format = PSB_2D_SRC_332RGB;
		dst_format = PSB_2D_DST_332RGB;
		break;
	case 15:
		src_format = PSB_2D_SRC_555RGB;
		dst_format = PSB_2D_DST_555RGB;
		break;
	case 16:
		src_format = PSB_2D_SRC_565RGB;
		dst_format = PSB_2D_DST_565RGB;
		break;
	case 24:
	case 32:
		/* this is wrong but since we don't do blending its okay */
		src_format = PSB_2D_SRC_8888ARGB;
		dst_format = PSB_2D_DST_8888ARGB;
		break;
	default:
		/* software fallback */
		cfb_copyarea(info, a);
		return;
	}

	psb_accel_2d_copy(dev_priv,
			  offset, stride, src_format,
			  offset, stride, dst_format,
			  a->sx, a->sy, a->dx, a->dy, a->width, a->height);
}

void psbfb_copyarea(struct fb_info *info,
			   const struct fb_copyarea *region)
{
	if (unlikely(info->state != FBINFO_STATE_RUNNING))
		return;

	if (info->flags & FBINFO_HWACCEL_DISABLED)
		return cfb_copyarea(info, region);

	/* psb_check_power_state(dev, PSB_DEVICE_SGX); */
	psbfb_copyarea_accel(info, region);
	/* Need to power back off here for MRST FIXMEAC */
}

void psbfb_imageblit(struct fb_info *info, const struct fb_image *image)
{
        /* For now */
	cfb_imageblit(info, image);
}

int psbfb_sync(struct fb_info *info)
{
	struct psb_fbdev *fbdev = info->par;
	struct psb_framebuffer *psbfb = fbdev->pfb;
	struct drm_device *dev = psbfb->base.dev;
	struct drm_psb_private *dev_priv = dev->dev_private;
	unsigned long _end = jiffies + DRM_HZ;
	int busy = 0;

#if 0
        /* Just a way to quickly test if cmd issue explodes */
	u32 test[2] = {
	        PSB_2D_FENCE_BH,
        };
	psbfb_2d_submit(dev_priv, test, 1);
#endif	
	/*
	 * First idle the 2D engine.
	 */

	if ((PSB_RSGX32(PSB_CR_2D_SOCIF) == _PSB_C2_SOCIF_EMPTY) &&
	    ((PSB_RSGX32(PSB_CR_2D_BLIT_STATUS) & _PSB_C2B_STATUS_BUSY) == 0))
		goto out;

	do {
		busy = (PSB_RSGX32(PSB_CR_2D_SOCIF) != _PSB_C2_SOCIF_EMPTY);
		cpu_relax();
	} while (busy && !time_after_eq(jiffies, _end));

	if (busy)
		busy = (PSB_RSGX32(PSB_CR_2D_SOCIF) != _PSB_C2_SOCIF_EMPTY);
	if (busy)
		goto out;

	do {
		busy = ((PSB_RSGX32(PSB_CR_2D_BLIT_STATUS) &
						_PSB_C2B_STATUS_BUSY) != 0);
		cpu_relax();
	} while (busy && !time_after_eq(jiffies, _end));
	if (busy)
		busy = ((PSB_RSGX32(PSB_CR_2D_BLIT_STATUS) &
					_PSB_C2B_STATUS_BUSY) != 0);

out:
	return (busy) ? -EBUSY : 0;
}

/*
	info->fix.accel = FB_ACCEL_I830;
	info->flags = FBINFO_DEFAULT;
*/