gma500: introduce the framebuffer support code

/**************************************************************************

 * Copyright (c) 2007-2011, 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 "framebuffer.h"

/**

 *	psb_spank		-	reset the 2D engine

 *	@dev_priv: our PSB DRM device

 *

 *	Soft reset the graphics engine and then reload the necessary registers.

 *	We use this at initialisation time but it will become relevant for

 *	accelerated X later

 */

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);

	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->gtt.gatt_start, PSB_CR_BIF_TWOD_REQ_BASE);

}

/**

 *	psb2_2d_wait_available	-	wait for FIFO room

 *	@dev_priv: our DRM device

 *	@size: size (in dwords) of the command we want to issue

 *

 *	Wait until there is room to load the FIFO with our data. If the

 *	device is not responding then reset it

 */

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;

}

/**

 *	psb_2d_submit		-	submit a 2D command

 *	@dev_priv: our DRM device

 *	@cmdbuf: command to issue

 *	@size: length (in dwords)

 *

 *	Issue one or more 2D commands to the accelerator. This needs to be

 *	serialized later when we add the GEM interfaces for acceleration

 */

static int psbfb_2d_submit(struct drm_psb_private *dev_priv, uint32_t *cmdbuf,

								unsigned size)

{

	int ret = 0;

	int i;

	unsigned submit_size;

	mutex_lock(&dev_priv->mutex_2d);

	while (size > 0) {

		submit_size = (size < 0x60) ? size : 0x60;

		size -= submit_size;

		ret = psb_2d_wait_available(dev_priv, submit_size);

		if (ret)

		        break;

		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);

	}

	mutex_unlock(&dev_priv->mutex_2d);

	return ret;

}

/**

 *	psb_accel_2d_copy_direction	-	compute blit order

 *	@xdir: X direction of move

 *	@ydir: Y direction of move

 *

 *	Compute the correct order setings to ensure that an overlapping blit

 *	correctly copies all the pixels.

 */

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;

}

/**

 *	psb_accel_2d_copy		-	accelerated 2D copy

 *	@dev_priv: our DRM device

 *	@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

 *

 *	Format and issue a 2D accelerated copy command.

 */

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);

}

/**

 *	psbfb_copyarea_accel	-	copyarea acceleration for /dev/fb

 *	@info: our framebuffer

 *	@a: copyarea parameters from the framebuffer core

 *

 *	Perform a 2D copy via the accelerator

 */

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;

	}

	if (!gma_power_begin(dev, false)) {

		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);

	gma_power_end(dev);

}

/**

 *	psbfb_copyarea	-	2D copy interface

 *	@info: our framebuffer

 *	@region: region to copy

 *

 *	Copy an area of the framebuffer console either by the accelerator

 *	or directly using the cfb helpers according to the request

 */

void psbfb_copyarea(struct fb_info *info,

			   const struct fb_copyarea *region)

{

	if (unlikely(info->state != FBINFO_STATE_RUNNING))

		return;

	/* Avoid the 8 pixel erratum */

	if (region->width == 8 || region->height == 8 ||

		(info->flags & FBINFO_HWACCEL_DISABLED))

		return cfb_copyarea(info, region);

	psbfb_copyarea_accel(info, region);

}

/**

 *	psbfb_sync	-	synchronize 2D

 *	@info: our framebuffer

 *

 *	Wait for the 2D engine to quiesce so that we can do CPU

 *	access to the framebuffer again

 */

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;

	mutex_lock(&dev_priv->mutex_2d);

	/*

	 * 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:

	mutex_unlock(&dev_priv->mutex_2d);

	return (busy) ? -EBUSY : 0;

}