drivers/char/drm/ffb_context.c - fp2-dev/kernel/msm - Gitiles

 /* $Id: ffb_context.c,v 1.5 2001/08/09 17:47:51 davem Exp $
  * ffb_context.c: Creator/Creator3D DRI/DRM context switching.
  *
  * Copyright (C) 2000 David S. Miller (davem@redhat.com)
  *
  * Almost entirely stolen from tdfx_context.c, see there
  * for authors.
  */

 #include <linux/sched.h>
 #include <asm/upa.h>

 #include "ffb.h"
 #include "drmP.h"

 #include "ffb_drv.h"

 static int DRM(alloc_queue) (drm_device_t * dev, int is_2d_only) {
 	ffb_dev_priv_t *fpriv = (ffb_dev_priv_t *) dev->dev_private;
 	int i;

 	for (i = 0; i < FFB_MAX_CTXS; i++) {
 		if (fpriv->hw_state[i] == NULL)
 			break;
 	}
 	if (i == FFB_MAX_CTXS)
 		return -1;

 	fpriv->hw_state[i] = kmalloc(sizeof(struct ffb_hw_context), GFP_KERNEL);
 	if (fpriv->hw_state[i] == NULL)
 		return -1;

 	fpriv->hw_state[i]->is_2d_only = is_2d_only;

 	/* Plus one because 0 is the special DRM_KERNEL_CONTEXT. */
 	return i + 1;
 }

 static void ffb_save_context(ffb_dev_priv_t * fpriv, int idx)
 {
 	ffb_fbcPtr ffb = fpriv->regs;
 	struct ffb_hw_context *ctx;
 	int i;

 	ctx = fpriv->hw_state[idx - 1];
 	if (idx == 0 || ctx == NULL)
 		return;

 	if (ctx->is_2d_only) {
 		/* 2D applications only care about certain pieces
 		 * of state.
 		 */
 		ctx->drawop = upa_readl(&ffb->drawop);
 		ctx->ppc = upa_readl(&ffb->ppc);
 		ctx->wid = upa_readl(&ffb->wid);
 		ctx->fg = upa_readl(&ffb->fg);
 		ctx->bg = upa_readl(&ffb->bg);
 		ctx->xclip = upa_readl(&ffb->xclip);
 		ctx->fbc = upa_readl(&ffb->fbc);
 		ctx->rop = upa_readl(&ffb->rop);
 		ctx->cmp = upa_readl(&ffb->cmp);
 		ctx->matchab = upa_readl(&ffb->matchab);
 		ctx->magnab = upa_readl(&ffb->magnab);
 		ctx->pmask = upa_readl(&ffb->pmask);
 		ctx->xpmask = upa_readl(&ffb->xpmask);
 		ctx->lpat = upa_readl(&ffb->lpat);
 		ctx->fontxy = upa_readl(&ffb->fontxy);
 		ctx->fontw = upa_readl(&ffb->fontw);
 		ctx->fontinc = upa_readl(&ffb->fontinc);

 		/* stencil/stencilctl only exists on FFB2+ and later
 		 * due to the introduction of 3DRAM-III.
 		 */
 		if (fpriv->ffb_type == ffb2_vertical_plus ||
 		    fpriv->ffb_type == ffb2_horizontal_plus) {
 			ctx->stencil = upa_readl(&ffb->stencil);
 			ctx->stencilctl = upa_readl(&ffb->stencilctl);
 		}

 		for (i = 0; i < 32; i++)
 			ctx->area_pattern[i] = upa_readl(&ffb->pattern[i]);
 		ctx->ucsr = upa_readl(&ffb->ucsr);
 		return;
 	}

 	/* Fetch drawop. */
 	ctx->drawop = upa_readl(&ffb->drawop);

 	/* If we were saving the vertex registers, this is where
 	 * we would do it.  We would save 32 32-bit words starting
 	 * at ffb->suvtx.
 	 */

 	/* Capture rendering attributes. */

 	ctx->ppc = upa_readl(&ffb->ppc);	/* Pixel Processor Control */
 	ctx->wid = upa_readl(&ffb->wid);	/* Current WID */
 	ctx->fg = upa_readl(&ffb->fg);	/* Constant FG color */
 	ctx->bg = upa_readl(&ffb->bg);	/* Constant BG color */
 	ctx->consty = upa_readl(&ffb->consty);	/* Constant Y */
 	ctx->constz = upa_readl(&ffb->constz);	/* Constant Z */
 	ctx->xclip = upa_readl(&ffb->xclip);	/* X plane clip */
 	ctx->dcss = upa_readl(&ffb->dcss);	/* Depth Cue Scale Slope */
 	ctx->vclipmin = upa_readl(&ffb->vclipmin);	/* Primary XY clip, minimum */
 	ctx->vclipmax = upa_readl(&ffb->vclipmax);	/* Primary XY clip, maximum */
 	ctx->vclipzmin = upa_readl(&ffb->vclipzmin);	/* Primary Z clip, minimum */
 	ctx->vclipzmax = upa_readl(&ffb->vclipzmax);	/* Primary Z clip, maximum */
 	ctx->dcsf = upa_readl(&ffb->dcsf);	/* Depth Cue Scale Front Bound */
 	ctx->dcsb = upa_readl(&ffb->dcsb);	/* Depth Cue Scale Back Bound */
 	ctx->dczf = upa_readl(&ffb->dczf);	/* Depth Cue Scale Z Front */
 	ctx->dczb = upa_readl(&ffb->dczb);	/* Depth Cue Scale Z Back */
 	ctx->blendc = upa_readl(&ffb->blendc);	/* Alpha Blend Control */
 	ctx->blendc1 = upa_readl(&ffb->blendc1);	/* Alpha Blend Color 1 */
 	ctx->blendc2 = upa_readl(&ffb->blendc2);	/* Alpha Blend Color 2 */
 	ctx->fbc = upa_readl(&ffb->fbc);	/* Frame Buffer Control */
 	ctx->rop = upa_readl(&ffb->rop);	/* Raster Operation */
 	ctx->cmp = upa_readl(&ffb->cmp);	/* Compare Controls */
 	ctx->matchab = upa_readl(&ffb->matchab);	/* Buffer A/B Match Ops */
 	ctx->matchc = upa_readl(&ffb->matchc);	/* Buffer C Match Ops */
 	ctx->magnab = upa_readl(&ffb->magnab);	/* Buffer A/B Magnitude Ops */
 	ctx->magnc = upa_readl(&ffb->magnc);	/* Buffer C Magnitude Ops */
 	ctx->pmask = upa_readl(&ffb->pmask);	/* RGB Plane Mask */
 	ctx->xpmask = upa_readl(&ffb->xpmask);	/* X Plane Mask */
 	ctx->ypmask = upa_readl(&ffb->ypmask);	/* Y Plane Mask */
 	ctx->zpmask = upa_readl(&ffb->zpmask);	/* Z Plane Mask */

 	/* Auxiliary Clips. */
 	ctx->auxclip0min = upa_readl(&ffb->auxclip[0].min);
 	ctx->auxclip0max = upa_readl(&ffb->auxclip[0].max);
 	ctx->auxclip1min = upa_readl(&ffb->auxclip[1].min);
 	ctx->auxclip1max = upa_readl(&ffb->auxclip[1].max);
 	ctx->auxclip2min = upa_readl(&ffb->auxclip[2].min);
 	ctx->auxclip2max = upa_readl(&ffb->auxclip[2].max);
 	ctx->auxclip3min = upa_readl(&ffb->auxclip[3].min);
 	ctx->auxclip3max = upa_readl(&ffb->auxclip[3].max);

 	ctx->lpat = upa_readl(&ffb->lpat);	/* Line Pattern */
 	ctx->fontxy = upa_readl(&ffb->fontxy);	/* XY Font Coordinate */
 	ctx->fontw = upa_readl(&ffb->fontw);	/* Font Width */
 	ctx->fontinc = upa_readl(&ffb->fontinc);	/* Font X/Y Increment */

 	/* These registers/features only exist on FFB2 and later chips. */
 	if (fpriv->ffb_type >= ffb2_prototype) {
 		ctx->dcss1 = upa_readl(&ffb->dcss1);	/* Depth Cue Scale Slope 1 */
 		ctx->dcss2 = upa_readl(&ffb->dcss2);	/* Depth Cue Scale Slope 2 */
 		ctx->dcss2 = upa_readl(&ffb->dcss3);	/* Depth Cue Scale Slope 3 */
 		ctx->dcs2 = upa_readl(&ffb->dcs2);	/* Depth Cue Scale 2 */
 		ctx->dcs3 = upa_readl(&ffb->dcs3);	/* Depth Cue Scale 3 */
 		ctx->dcs4 = upa_readl(&ffb->dcs4);	/* Depth Cue Scale 4 */
 		ctx->dcd2 = upa_readl(&ffb->dcd2);	/* Depth Cue Depth 2 */
 		ctx->dcd3 = upa_readl(&ffb->dcd3);	/* Depth Cue Depth 3 */
 		ctx->dcd4 = upa_readl(&ffb->dcd4);	/* Depth Cue Depth 4 */

 		/* And stencil/stencilctl only exists on FFB2+ and later
 		 * due to the introduction of 3DRAM-III.
 		 */
 		if (fpriv->ffb_type == ffb2_vertical_plus ||
 		    fpriv->ffb_type == ffb2_horizontal_plus) {
 			ctx->stencil = upa_readl(&ffb->stencil);
 			ctx->stencilctl = upa_readl(&ffb->stencilctl);
 		}
 	}

 	/* Save the 32x32 area pattern. */
 	for (i = 0; i < 32; i++)
 		ctx->area_pattern[i] = upa_readl(&ffb->pattern[i]);

 	/* Finally, stash away the User Constol/Status Register. */
 	ctx->ucsr = upa_readl(&ffb->ucsr);
 }

 static void ffb_restore_context(ffb_dev_priv_t * fpriv, int old, int idx)
 {
 	ffb_fbcPtr ffb = fpriv->regs;
 	struct ffb_hw_context *ctx;
 	int i;

 	ctx = fpriv->hw_state[idx - 1];
 	if (idx == 0 || ctx == NULL)
 		return;

 	if (ctx->is_2d_only) {
 		/* 2D applications only care about certain pieces
 		 * of state.
 		 */
 		upa_writel(ctx->drawop, &ffb->drawop);

 		/* If we were restoring the vertex registers, this is where
 		 * we would do it.  We would restore 32 32-bit words starting
 		 * at ffb->suvtx.
 		 */

 		upa_writel(ctx->ppc, &ffb->ppc);
 		upa_writel(ctx->wid, &ffb->wid);
 		upa_writel(ctx->fg, &ffb->fg);
 		upa_writel(ctx->bg, &ffb->bg);
 		upa_writel(ctx->xclip, &ffb->xclip);
 		upa_writel(ctx->fbc, &ffb->fbc);
 		upa_writel(ctx->rop, &ffb->rop);
 		upa_writel(ctx->cmp, &ffb->cmp);
 		upa_writel(ctx->matchab, &ffb->matchab);
 		upa_writel(ctx->magnab, &ffb->magnab);
 		upa_writel(ctx->pmask, &ffb->pmask);
 		upa_writel(ctx->xpmask, &ffb->xpmask);
 		upa_writel(ctx->lpat, &ffb->lpat);
 		upa_writel(ctx->fontxy, &ffb->fontxy);
 		upa_writel(ctx->fontw, &ffb->fontw);
 		upa_writel(ctx->fontinc, &ffb->fontinc);

 		/* stencil/stencilctl only exists on FFB2+ and later
 		 * due to the introduction of 3DRAM-III.
 		 */
 		if (fpriv->ffb_type == ffb2_vertical_plus ||
 		    fpriv->ffb_type == ffb2_horizontal_plus) {
 			upa_writel(ctx->stencil, &ffb->stencil);
 			upa_writel(ctx->stencilctl, &ffb->stencilctl);
 			upa_writel(0x80000000, &ffb->fbc);
 			upa_writel((ctx->stencilctl | 0x80000),
 				   &ffb->rawstencilctl);
 			upa_writel(ctx->fbc, &ffb->fbc);
 		}

 		for (i = 0; i < 32; i++)
 			upa_writel(ctx->area_pattern[i], &ffb->pattern[i]);
 		upa_writel((ctx->ucsr & 0xf0000), &ffb->ucsr);
 		return;
 	}

 	/* Restore drawop. */
 	upa_writel(ctx->drawop, &ffb->drawop);

 	/* If we were restoring the vertex registers, this is where
 	 * we would do it.  We would restore 32 32-bit words starting
 	 * at ffb->suvtx.
 	 */

 	/* Restore rendering attributes. */

 	upa_writel(ctx->ppc, &ffb->ppc);	/* Pixel Processor Control */
 	upa_writel(ctx->wid, &ffb->wid);	/* Current WID */
 	upa_writel(ctx->fg, &ffb->fg);	/* Constant FG color */
 	upa_writel(ctx->bg, &ffb->bg);	/* Constant BG color */
 	upa_writel(ctx->consty, &ffb->consty);	/* Constant Y */
 	upa_writel(ctx->constz, &ffb->constz);	/* Constant Z */
 	upa_writel(ctx->xclip, &ffb->xclip);	/* X plane clip */
 	upa_writel(ctx->dcss, &ffb->dcss);	/* Depth Cue Scale Slope */
 	upa_writel(ctx->vclipmin, &ffb->vclipmin);	/* Primary XY clip, minimum */
 	upa_writel(ctx->vclipmax, &ffb->vclipmax);	/* Primary XY clip, maximum */
 	upa_writel(ctx->vclipzmin, &ffb->vclipzmin);	/* Primary Z clip, minimum */
 	upa_writel(ctx->vclipzmax, &ffb->vclipzmax);	/* Primary Z clip, maximum */
 	upa_writel(ctx->dcsf, &ffb->dcsf);	/* Depth Cue Scale Front Bound */
 	upa_writel(ctx->dcsb, &ffb->dcsb);	/* Depth Cue Scale Back Bound */
 	upa_writel(ctx->dczf, &ffb->dczf);	/* Depth Cue Scale Z Front */
 	upa_writel(ctx->dczb, &ffb->dczb);	/* Depth Cue Scale Z Back */
 	upa_writel(ctx->blendc, &ffb->blendc);	/* Alpha Blend Control */
 	upa_writel(ctx->blendc1, &ffb->blendc1);	/* Alpha Blend Color 1 */
 	upa_writel(ctx->blendc2, &ffb->blendc2);	/* Alpha Blend Color 2 */
 	upa_writel(ctx->fbc, &ffb->fbc);	/* Frame Buffer Control */
 	upa_writel(ctx->rop, &ffb->rop);	/* Raster Operation */
 	upa_writel(ctx->cmp, &ffb->cmp);	/* Compare Controls */
 	upa_writel(ctx->matchab, &ffb->matchab);	/* Buffer A/B Match Ops */
 	upa_writel(ctx->matchc, &ffb->matchc);	/* Buffer C Match Ops */
 	upa_writel(ctx->magnab, &ffb->magnab);	/* Buffer A/B Magnitude Ops */
 	upa_writel(ctx->magnc, &ffb->magnc);	/* Buffer C Magnitude Ops */
 	upa_writel(ctx->pmask, &ffb->pmask);	/* RGB Plane Mask */
 	upa_writel(ctx->xpmask, &ffb->xpmask);	/* X Plane Mask */
 	upa_writel(ctx->ypmask, &ffb->ypmask);	/* Y Plane Mask */
 	upa_writel(ctx->zpmask, &ffb->zpmask);	/* Z Plane Mask */

 	/* Auxiliary Clips. */
 	upa_writel(ctx->auxclip0min, &ffb->auxclip[0].min);
 	upa_writel(ctx->auxclip0max, &ffb->auxclip[0].max);
 	upa_writel(ctx->auxclip1min, &ffb->auxclip[1].min);
 	upa_writel(ctx->auxclip1max, &ffb->auxclip[1].max);
 	upa_writel(ctx->auxclip2min, &ffb->auxclip[2].min);
 	upa_writel(ctx->auxclip2max, &ffb->auxclip[2].max);
 	upa_writel(ctx->auxclip3min, &ffb->auxclip[3].min);
 	upa_writel(ctx->auxclip3max, &ffb->auxclip[3].max);

 	upa_writel(ctx->lpat, &ffb->lpat);	/* Line Pattern */
 	upa_writel(ctx->fontxy, &ffb->fontxy);	/* XY Font Coordinate */
 	upa_writel(ctx->fontw, &ffb->fontw);	/* Font Width */
 	upa_writel(ctx->fontinc, &ffb->fontinc);	/* Font X/Y Increment */

 	/* These registers/features only exist on FFB2 and later chips. */
 	if (fpriv->ffb_type >= ffb2_prototype) {
 		upa_writel(ctx->dcss1, &ffb->dcss1);	/* Depth Cue Scale Slope 1 */
 		upa_writel(ctx->dcss2, &ffb->dcss2);	/* Depth Cue Scale Slope 2 */
 		upa_writel(ctx->dcss3, &ffb->dcss2);	/* Depth Cue Scale Slope 3 */
 		upa_writel(ctx->dcs2, &ffb->dcs2);	/* Depth Cue Scale 2 */
 		upa_writel(ctx->dcs3, &ffb->dcs3);	/* Depth Cue Scale 3 */
 		upa_writel(ctx->dcs4, &ffb->dcs4);	/* Depth Cue Scale 4 */
 		upa_writel(ctx->dcd2, &ffb->dcd2);	/* Depth Cue Depth 2 */
 		upa_writel(ctx->dcd3, &ffb->dcd3);	/* Depth Cue Depth 3 */
 		upa_writel(ctx->dcd4, &ffb->dcd4);	/* Depth Cue Depth 4 */

 		/* And stencil/stencilctl only exists on FFB2+ and later
 		 * due to the introduction of 3DRAM-III.
 		 */
 		if (fpriv->ffb_type == ffb2_vertical_plus ||
 		    fpriv->ffb_type == ffb2_horizontal_plus) {
 			/* Unfortunately, there is a hardware bug on
 			 * the FFB2+ chips which prevents a normal write
 			 * to the stencil control register from working
 			 * as it should.
 			 *
 			 * The state controlled by the FFB stencilctl register
 			 * really gets transferred to the per-buffer instances
 			 * of the stencilctl register in the 3DRAM chips.
 			 *
 			 * The bug is that FFB does not update buffer C correctly,
 			 * so we have to do it by hand for them.
 			 */

 			/* This will update buffers A and B. */
 			upa_writel(ctx->stencil, &ffb->stencil);
 			upa_writel(ctx->stencilctl, &ffb->stencilctl);

 			/* Force FFB to use buffer C 3dram regs. */
 			upa_writel(0x80000000, &ffb->fbc);
 			upa_writel((ctx->stencilctl | 0x80000),
 				   &ffb->rawstencilctl);

 			/* Now restore the correct FBC controls. */
 			upa_writel(ctx->fbc, &ffb->fbc);
 		}
 	}

 	/* Restore the 32x32 area pattern. */
 	for (i = 0; i < 32; i++)
 		upa_writel(ctx->area_pattern[i], &ffb->pattern[i]);

 	/* Finally, stash away the User Constol/Status Register.
 	 * The only state we really preserve here is the picking
 	 * control.
 	 */
 	upa_writel((ctx->ucsr & 0xf0000), &ffb->ucsr);
 }

 #define FFB_UCSR_FB_BUSY       0x01000000
 #define FFB_UCSR_RP_BUSY       0x02000000
 #define FFB_UCSR_ALL_BUSY      (FFB_UCSR_RP_BUSY|FFB_UCSR_FB_BUSY)

 static void FFBWait(ffb_fbcPtr ffb)
 {
 	int limit = 100000;

 	do {
 		u32 regval = upa_readl(&ffb->ucsr);

 		if ((regval & FFB_UCSR_ALL_BUSY) == 0)
 			break;
 	} while (--limit);
 }

 int ffb_driver_context_switch(drm_device_t * dev, int old, int new)
 {
 	ffb_dev_priv_t *fpriv = (ffb_dev_priv_t *) dev->dev_private;

 #ifdef DRM_DMA_HISTOGRAM
 	dev->ctx_start = get_cycles();
 #endif

 	DRM_DEBUG("Context switch from %d to %d\n", old, new);

 	if (new == dev->last_context || dev->last_context == 0) {
 		dev->last_context = new;
 		return 0;
 	}

 	FFBWait(fpriv->regs);
 	ffb_save_context(fpriv, old);
 	ffb_restore_context(fpriv, old, new);
 	FFBWait(fpriv->regs);

 	dev->last_context = new;

 	return 0;
 }

 int ffb_driver_resctx(struct inode *inode, struct file *filp, unsigned int cmd,
 		      unsigned long arg)
 {
 	drm_ctx_res_t res;
 	drm_ctx_t ctx;
 	int i;

 	DRM_DEBUG("%d\n", DRM_RESERVED_CONTEXTS);
 	if (copy_from_user(&res, (drm_ctx_res_t __user *) arg, sizeof(res)))
 		return -EFAULT;
 	if (res.count >= DRM_RESERVED_CONTEXTS) {
 		memset(&ctx, 0, sizeof(ctx));
 		for (i = 0; i < DRM_RESERVED_CONTEXTS; i++) {
 			ctx.handle = i;
 			if (copy_to_user(&res.contexts[i], &i, sizeof(i)))
 				return -EFAULT;
 		}
 	}
 	res.count = DRM_RESERVED_CONTEXTS;
 	if (copy_to_user((drm_ctx_res_t __user *) arg, &res, sizeof(res)))
 		return -EFAULT;
 	return 0;
 }

 int ffb_driver_addctx(struct inode *inode, struct file *filp, unsigned int cmd,
 		      unsigned long arg)
 {
 	drm_file_t *priv = filp->private_data;
 	drm_device_t *dev = priv->dev;
 	drm_ctx_t ctx;
 	int idx;

 	if (copy_from_user(&ctx, (drm_ctx_t __user *) arg, sizeof(ctx)))
 		return -EFAULT;
 	idx = DRM(alloc_queue) (dev, (ctx.flags & _DRM_CONTEXT_2DONLY));
 	if (idx < 0)
 		return -ENFILE;

 	DRM_DEBUG("%d\n", ctx.handle);
 	ctx.handle = idx;
 	if (copy_to_user((drm_ctx_t __user *) arg, &ctx, sizeof(ctx)))
 		return -EFAULT;
 	return 0;
 }

 int ffb_driver_modctx(struct inode *inode, struct file *filp, unsigned int cmd,
 		      unsigned long arg)
 {
 	drm_file_t *priv = filp->private_data;
 	drm_device_t *dev = priv->dev;
 	ffb_dev_priv_t *fpriv = (ffb_dev_priv_t *) dev->dev_private;
 	struct ffb_hw_context *hwctx;
 	drm_ctx_t ctx;
 	int idx;

 	if (copy_from_user(&ctx, (drm_ctx_t __user *) arg, sizeof(ctx)))
 		return -EFAULT;

 	idx = ctx.handle;
 	if (idx <= 0 || idx >= FFB_MAX_CTXS)
 		return -EINVAL;

 	hwctx = fpriv->hw_state[idx - 1];
 	if (hwctx == NULL)
 		return -EINVAL;

 	if ((ctx.flags & _DRM_CONTEXT_2DONLY) == 0)
 		hwctx->is_2d_only = 0;
 	else
 		hwctx->is_2d_only = 1;

 	return 0;
 }

 int ffb_driver_getctx(struct inode *inode, struct file *filp, unsigned int cmd,
 		      unsigned long arg)
 {
 	drm_file_t *priv = filp->private_data;
 	drm_device_t *dev = priv->dev;
 	ffb_dev_priv_t *fpriv = (ffb_dev_priv_t *) dev->dev_private;
 	struct ffb_hw_context *hwctx;
 	drm_ctx_t ctx;
 	int idx;

 	if (copy_from_user(&ctx, (drm_ctx_t __user *) arg, sizeof(ctx)))
 		return -EFAULT;

 	idx = ctx.handle;
 	if (idx <= 0 || idx >= FFB_MAX_CTXS)
 		return -EINVAL;

 	hwctx = fpriv->hw_state[idx - 1];
 	if (hwctx == NULL)
 		return -EINVAL;

 	if (hwctx->is_2d_only != 0)
 		ctx.flags = _DRM_CONTEXT_2DONLY;
 	else
 		ctx.flags = 0;

 	if (copy_to_user((drm_ctx_t __user *) arg, &ctx, sizeof(ctx)))
 		return -EFAULT;

 	return 0;
 }

 int ffb_driver_switchctx(struct inode *inode, struct file *filp,
 			 unsigned int cmd, unsigned long arg)
 {
 	drm_file_t *priv = filp->private_data;
 	drm_device_t *dev = priv->dev;
 	drm_ctx_t ctx;

 	if (copy_from_user(&ctx, (drm_ctx_t __user *) arg, sizeof(ctx)))
 		return -EFAULT;
 	DRM_DEBUG("%d\n", ctx.handle);
 	return ffb_driver_context_switch(dev, dev->last_context, ctx.handle);
 }

 int ffb_driver_newctx(struct inode *inode, struct file *filp, unsigned int cmd,
 		      unsigned long arg)
 {
 	drm_ctx_t ctx;

 	if (copy_from_user(&ctx, (drm_ctx_t __user *) arg, sizeof(ctx)))
 		return -EFAULT;
 	DRM_DEBUG("%d\n", ctx.handle);

 	return 0;
 }

 int ffb_driver_rmctx(struct inode *inode, struct file *filp, unsigned int cmd,
 		     unsigned long arg)
 {
 	drm_ctx_t ctx;
 	drm_file_t *priv = filp->private_data;
 	drm_device_t *dev = priv->dev;
 	ffb_dev_priv_t *fpriv = (ffb_dev_priv_t *) dev->dev_private;
 	int idx;

 	if (copy_from_user(&ctx, (drm_ctx_t __user *) arg, sizeof(ctx)))
 		return -EFAULT;
 	DRM_DEBUG("%d\n", ctx.handle);

 	idx = ctx.handle - 1;
 	if (idx < 0 || idx >= FFB_MAX_CTXS)
 		return -EINVAL;

 	if (fpriv->hw_state[idx] != NULL) {
 		kfree(fpriv->hw_state[idx]);
 		fpriv->hw_state[idx] = NULL;
 	}
 	return 0;
 }

 void ffb_set_context_ioctls(void)
 {
 	DRM(ioctls)[DRM_IOCTL_NR(DRM_IOCTL_ADD_CTX)].func = ffb_driver_addctx;
 	DRM(ioctls)[DRM_IOCTL_NR(DRM_IOCTL_RM_CTX)].func = ffb_driver_rmctx;
 	DRM(ioctls)[DRM_IOCTL_NR(DRM_IOCTL_MOD_CTX)].func = ffb_driver_modctx;
 	DRM(ioctls)[DRM_IOCTL_NR(DRM_IOCTL_GET_CTX)].func = ffb_driver_getctx;
 	DRM(ioctls)[DRM_IOCTL_NR(DRM_IOCTL_SWITCH_CTX)].func =
 	    ffb_driver_switchctx;
 	DRM(ioctls)[DRM_IOCTL_NR(DRM_IOCTL_NEW_CTX)].func = ffb_driver_newctx;
 	DRM(ioctls)[DRM_IOCTL_NR(DRM_IOCTL_RES_CTX)].func = ffb_driver_resctx;

 }
	/* $Id: ffb_context.c,v 1.5 2001/08/09 17:47:51 davem Exp $
	* ffb_context.c: Creator/Creator3D DRI/DRM context switching.
	*
	* Copyright (C) 2000 David S. Miller (davem@redhat.com)
	*
	* Almost entirely stolen from tdfx_context.c, see there
	* for authors.
	*/

	#include <linux/sched.h>
	#include <asm/upa.h>

	#include "ffb.h"
	#include "drmP.h"

	#include "ffb_drv.h"

	static int DRM(alloc_queue) (drm_device_t * dev, int is_2d_only) {
	ffb_dev_priv_t fpriv = (ffb_dev_priv_t ) dev->dev_private;
	int i;

	for (i = 0; i < FFB_MAX_CTXS; i++) {
	if (fpriv->hw_state[i] == NULL)
	break;
	}
	if (i == FFB_MAX_CTXS)
	return -1;

	fpriv->hw_state[i] = kmalloc(sizeof(struct ffb_hw_context), GFP_KERNEL);
	if (fpriv->hw_state[i] == NULL)
	return -1;

	fpriv->hw_state[i]->is_2d_only = is_2d_only;

	/* Plus one because 0 is the special DRM_KERNEL_CONTEXT. */
	return i + 1;
	}

	static void ffb_save_context(ffb_dev_priv_t * fpriv, int idx)
	{
	ffb_fbcPtr ffb = fpriv->regs;
	struct ffb_hw_context *ctx;
	int i;

	ctx = fpriv->hw_state[idx - 1];
	if (idx == 0 \|\| ctx == NULL)
	return;

	if (ctx->is_2d_only) {
	/* 2D applications only care about certain pieces
	* of state.
	*/
	ctx->drawop = upa_readl(&ffb->drawop);
	ctx->ppc = upa_readl(&ffb->ppc);
	ctx->wid = upa_readl(&ffb->wid);
	ctx->fg = upa_readl(&ffb->fg);
	ctx->bg = upa_readl(&ffb->bg);
	ctx->xclip = upa_readl(&ffb->xclip);
	ctx->fbc = upa_readl(&ffb->fbc);
	ctx->rop = upa_readl(&ffb->rop);
	ctx->cmp = upa_readl(&ffb->cmp);
	ctx->matchab = upa_readl(&ffb->matchab);
	ctx->magnab = upa_readl(&ffb->magnab);
	ctx->pmask = upa_readl(&ffb->pmask);
	ctx->xpmask = upa_readl(&ffb->xpmask);
	ctx->lpat = upa_readl(&ffb->lpat);
	ctx->fontxy = upa_readl(&ffb->fontxy);
	ctx->fontw = upa_readl(&ffb->fontw);
	ctx->fontinc = upa_readl(&ffb->fontinc);

	/* stencil/stencilctl only exists on FFB2+ and later
	* due to the introduction of 3DRAM-III.
	*/
	if (fpriv->ffb_type == ffb2_vertical_plus \|\|
	fpriv->ffb_type == ffb2_horizontal_plus) {
	ctx->stencil = upa_readl(&ffb->stencil);
	ctx->stencilctl = upa_readl(&ffb->stencilctl);
	}

	for (i = 0; i < 32; i++)
	ctx->area_pattern[i] = upa_readl(&ffb->pattern[i]);
	ctx->ucsr = upa_readl(&ffb->ucsr);
	return;
	}

	/* Fetch drawop. */
	ctx->drawop = upa_readl(&ffb->drawop);

	/* If we were saving the vertex registers, this is where
	* we would do it. We would save 32 32-bit words starting
	* at ffb->suvtx.
	*/

	/* Capture rendering attributes. */

	ctx->ppc = upa_readl(&ffb->ppc); /* Pixel Processor Control */
	ctx->wid = upa_readl(&ffb->wid); /* Current WID */
	ctx->fg = upa_readl(&ffb->fg); /* Constant FG color */
	ctx->bg = upa_readl(&ffb->bg); /* Constant BG color */
	ctx->consty = upa_readl(&ffb->consty); /* Constant Y */
	ctx->constz = upa_readl(&ffb->constz); /* Constant Z */
	ctx->xclip = upa_readl(&ffb->xclip); /* X plane clip */
	ctx->dcss = upa_readl(&ffb->dcss); /* Depth Cue Scale Slope */
	ctx->vclipmin = upa_readl(&ffb->vclipmin); /* Primary XY clip, minimum */
	ctx->vclipmax = upa_readl(&ffb->vclipmax); /* Primary XY clip, maximum */
	ctx->vclipzmin = upa_readl(&ffb->vclipzmin); /* Primary Z clip, minimum */
	ctx->vclipzmax = upa_readl(&ffb->vclipzmax); /* Primary Z clip, maximum */
	ctx->dcsf = upa_readl(&ffb->dcsf); /* Depth Cue Scale Front Bound */
	ctx->dcsb = upa_readl(&ffb->dcsb); /* Depth Cue Scale Back Bound */
	ctx->dczf = upa_readl(&ffb->dczf); /* Depth Cue Scale Z Front */
	ctx->dczb = upa_readl(&ffb->dczb); /* Depth Cue Scale Z Back */
	ctx->blendc = upa_readl(&ffb->blendc); /* Alpha Blend Control */
	ctx->blendc1 = upa_readl(&ffb->blendc1); /* Alpha Blend Color 1 */
	ctx->blendc2 = upa_readl(&ffb->blendc2); /* Alpha Blend Color 2 */
	ctx->fbc = upa_readl(&ffb->fbc); /* Frame Buffer Control */
	ctx->rop = upa_readl(&ffb->rop); /* Raster Operation */
	ctx->cmp = upa_readl(&ffb->cmp); /* Compare Controls */
	ctx->matchab = upa_readl(&ffb->matchab); /* Buffer A/B Match Ops */
	ctx->matchc = upa_readl(&ffb->matchc); /* Buffer C Match Ops */
	ctx->magnab = upa_readl(&ffb->magnab); /* Buffer A/B Magnitude Ops */
	ctx->magnc = upa_readl(&ffb->magnc); /* Buffer C Magnitude Ops */
	ctx->pmask = upa_readl(&ffb->pmask); /* RGB Plane Mask */
	ctx->xpmask = upa_readl(&ffb->xpmask); /* X Plane Mask */
	ctx->ypmask = upa_readl(&ffb->ypmask); /* Y Plane Mask */
	ctx->zpmask = upa_readl(&ffb->zpmask); /* Z Plane Mask */

	/* Auxiliary Clips. */
	ctx->auxclip0min = upa_readl(&ffb->auxclip[0].min);
	ctx->auxclip0max = upa_readl(&ffb->auxclip[0].max);
	ctx->auxclip1min = upa_readl(&ffb->auxclip[1].min);
	ctx->auxclip1max = upa_readl(&ffb->auxclip[1].max);
	ctx->auxclip2min = upa_readl(&ffb->auxclip[2].min);
	ctx->auxclip2max = upa_readl(&ffb->auxclip[2].max);
	ctx->auxclip3min = upa_readl(&ffb->auxclip[3].min);
	ctx->auxclip3max = upa_readl(&ffb->auxclip[3].max);

	ctx->lpat = upa_readl(&ffb->lpat); /* Line Pattern */
	ctx->fontxy = upa_readl(&ffb->fontxy); /* XY Font Coordinate */
	ctx->fontw = upa_readl(&ffb->fontw); /* Font Width */
	ctx->fontinc = upa_readl(&ffb->fontinc); /* Font X/Y Increment */

	/* These registers/features only exist on FFB2 and later chips. */
	if (fpriv->ffb_type >= ffb2_prototype) {
	ctx->dcss1 = upa_readl(&ffb->dcss1); /* Depth Cue Scale Slope 1 */
	ctx->dcss2 = upa_readl(&ffb->dcss2); /* Depth Cue Scale Slope 2 */
	ctx->dcss2 = upa_readl(&ffb->dcss3); /* Depth Cue Scale Slope 3 */
	ctx->dcs2 = upa_readl(&ffb->dcs2); /* Depth Cue Scale 2 */
	ctx->dcs3 = upa_readl(&ffb->dcs3); /* Depth Cue Scale 3 */
	ctx->dcs4 = upa_readl(&ffb->dcs4); /* Depth Cue Scale 4 */
	ctx->dcd2 = upa_readl(&ffb->dcd2); /* Depth Cue Depth 2 */
	ctx->dcd3 = upa_readl(&ffb->dcd3); /* Depth Cue Depth 3 */
	ctx->dcd4 = upa_readl(&ffb->dcd4); /* Depth Cue Depth 4 */

	/* And stencil/stencilctl only exists on FFB2+ and later
	* due to the introduction of 3DRAM-III.
	*/
	if (fpriv->ffb_type == ffb2_vertical_plus \|\|
	fpriv->ffb_type == ffb2_horizontal_plus) {
	ctx->stencil = upa_readl(&ffb->stencil);
	ctx->stencilctl = upa_readl(&ffb->stencilctl);
	}
	}

	/* Save the 32x32 area pattern. */
	for (i = 0; i < 32; i++)
	ctx->area_pattern[i] = upa_readl(&ffb->pattern[i]);

	/* Finally, stash away the User Constol/Status Register. */
	ctx->ucsr = upa_readl(&ffb->ucsr);
	}

	static void ffb_restore_context(ffb_dev_priv_t * fpriv, int old, int idx)
	{
	ffb_fbcPtr ffb = fpriv->regs;
	struct ffb_hw_context *ctx;
	int i;

	ctx = fpriv->hw_state[idx - 1];
	if (idx == 0 \|\| ctx == NULL)
	return;

	if (ctx->is_2d_only) {
	/* 2D applications only care about certain pieces
	* of state.
	*/
	upa_writel(ctx->drawop, &ffb->drawop);

	/* If we were restoring the vertex registers, this is where
	* we would do it. We would restore 32 32-bit words starting
	* at ffb->suvtx.
	*/

	upa_writel(ctx->ppc, &ffb->ppc);
	upa_writel(ctx->wid, &ffb->wid);
	upa_writel(ctx->fg, &ffb->fg);
	upa_writel(ctx->bg, &ffb->bg);
	upa_writel(ctx->xclip, &ffb->xclip);
	upa_writel(ctx->fbc, &ffb->fbc);
	upa_writel(ctx->rop, &ffb->rop);
	upa_writel(ctx->cmp, &ffb->cmp);
	upa_writel(ctx->matchab, &ffb->matchab);
	upa_writel(ctx->magnab, &ffb->magnab);
	upa_writel(ctx->pmask, &ffb->pmask);
	upa_writel(ctx->xpmask, &ffb->xpmask);
	upa_writel(ctx->lpat, &ffb->lpat);
	upa_writel(ctx->fontxy, &ffb->fontxy);
	upa_writel(ctx->fontw, &ffb->fontw);
	upa_writel(ctx->fontinc, &ffb->fontinc);

	/* stencil/stencilctl only exists on FFB2+ and later
	* due to the introduction of 3DRAM-III.
	*/
	if (fpriv->ffb_type == ffb2_vertical_plus \|\|
	fpriv->ffb_type == ffb2_horizontal_plus) {
	upa_writel(ctx->stencil, &ffb->stencil);
	upa_writel(ctx->stencilctl, &ffb->stencilctl);
	upa_writel(0x80000000, &ffb->fbc);
	upa_writel((ctx->stencilctl \| 0x80000),
	&ffb->rawstencilctl);
	upa_writel(ctx->fbc, &ffb->fbc);
	}

	for (i = 0; i < 32; i++)
	upa_writel(ctx->area_pattern[i], &ffb->pattern[i]);
	upa_writel((ctx->ucsr & 0xf0000), &ffb->ucsr);
	return;
	}

	/* Restore drawop. */
	upa_writel(ctx->drawop, &ffb->drawop);

	/* If we were restoring the vertex registers, this is where
	* we would do it. We would restore 32 32-bit words starting
	* at ffb->suvtx.
	*/

	/* Restore rendering attributes. */

	upa_writel(ctx->ppc, &ffb->ppc); /* Pixel Processor Control */
	upa_writel(ctx->wid, &ffb->wid); /* Current WID */
	upa_writel(ctx->fg, &ffb->fg); /* Constant FG color */
	upa_writel(ctx->bg, &ffb->bg); /* Constant BG color */
	upa_writel(ctx->consty, &ffb->consty); /* Constant Y */
	upa_writel(ctx->constz, &ffb->constz); /* Constant Z */
	upa_writel(ctx->xclip, &ffb->xclip); /* X plane clip */
	upa_writel(ctx->dcss, &ffb->dcss); /* Depth Cue Scale Slope */
	upa_writel(ctx->vclipmin, &ffb->vclipmin); /* Primary XY clip, minimum */
	upa_writel(ctx->vclipmax, &ffb->vclipmax); /* Primary XY clip, maximum */
	upa_writel(ctx->vclipzmin, &ffb->vclipzmin); /* Primary Z clip, minimum */
	upa_writel(ctx->vclipzmax, &ffb->vclipzmax); /* Primary Z clip, maximum */
	upa_writel(ctx->dcsf, &ffb->dcsf); /* Depth Cue Scale Front Bound */
	upa_writel(ctx->dcsb, &ffb->dcsb); /* Depth Cue Scale Back Bound */
	upa_writel(ctx->dczf, &ffb->dczf); /* Depth Cue Scale Z Front */
	upa_writel(ctx->dczb, &ffb->dczb); /* Depth Cue Scale Z Back */
	upa_writel(ctx->blendc, &ffb->blendc); /* Alpha Blend Control */
	upa_writel(ctx->blendc1, &ffb->blendc1); /* Alpha Blend Color 1 */
	upa_writel(ctx->blendc2, &ffb->blendc2); /* Alpha Blend Color 2 */
	upa_writel(ctx->fbc, &ffb->fbc); /* Frame Buffer Control */
	upa_writel(ctx->rop, &ffb->rop); /* Raster Operation */
	upa_writel(ctx->cmp, &ffb->cmp); /* Compare Controls */
	upa_writel(ctx->matchab, &ffb->matchab); /* Buffer A/B Match Ops */
	upa_writel(ctx->matchc, &ffb->matchc); /* Buffer C Match Ops */
	upa_writel(ctx->magnab, &ffb->magnab); /* Buffer A/B Magnitude Ops */
	upa_writel(ctx->magnc, &ffb->magnc); /* Buffer C Magnitude Ops */
	upa_writel(ctx->pmask, &ffb->pmask); /* RGB Plane Mask */
	upa_writel(ctx->xpmask, &ffb->xpmask); /* X Plane Mask */
	upa_writel(ctx->ypmask, &ffb->ypmask); /* Y Plane Mask */
	upa_writel(ctx->zpmask, &ffb->zpmask); /* Z Plane Mask */

	/* Auxiliary Clips. */
	upa_writel(ctx->auxclip0min, &ffb->auxclip[0].min);
	upa_writel(ctx->auxclip0max, &ffb->auxclip[0].max);
	upa_writel(ctx->auxclip1min, &ffb->auxclip[1].min);
	upa_writel(ctx->auxclip1max, &ffb->auxclip[1].max);
	upa_writel(ctx->auxclip2min, &ffb->auxclip[2].min);
	upa_writel(ctx->auxclip2max, &ffb->auxclip[2].max);
	upa_writel(ctx->auxclip3min, &ffb->auxclip[3].min);
	upa_writel(ctx->auxclip3max, &ffb->auxclip[3].max);

	upa_writel(ctx->lpat, &ffb->lpat); /* Line Pattern */
	upa_writel(ctx->fontxy, &ffb->fontxy); /* XY Font Coordinate */
	upa_writel(ctx->fontw, &ffb->fontw); /* Font Width */
	upa_writel(ctx->fontinc, &ffb->fontinc); /* Font X/Y Increment */

	/* These registers/features only exist on FFB2 and later chips. */
	if (fpriv->ffb_type >= ffb2_prototype) {
	upa_writel(ctx->dcss1, &ffb->dcss1); /* Depth Cue Scale Slope 1 */
	upa_writel(ctx->dcss2, &ffb->dcss2); /* Depth Cue Scale Slope 2 */
	upa_writel(ctx->dcss3, &ffb->dcss2); /* Depth Cue Scale Slope 3 */
	upa_writel(ctx->dcs2, &ffb->dcs2); /* Depth Cue Scale 2 */
	upa_writel(ctx->dcs3, &ffb->dcs3); /* Depth Cue Scale 3 */
	upa_writel(ctx->dcs4, &ffb->dcs4); /* Depth Cue Scale 4 */
	upa_writel(ctx->dcd2, &ffb->dcd2); /* Depth Cue Depth 2 */
	upa_writel(ctx->dcd3, &ffb->dcd3); /* Depth Cue Depth 3 */
	upa_writel(ctx->dcd4, &ffb->dcd4); /* Depth Cue Depth 4 */

	/* And stencil/stencilctl only exists on FFB2+ and later
	* due to the introduction of 3DRAM-III.
	*/
	if (fpriv->ffb_type == ffb2_vertical_plus \|\|
	fpriv->ffb_type == ffb2_horizontal_plus) {
	/* Unfortunately, there is a hardware bug on
	* the FFB2+ chips which prevents a normal write
	* to the stencil control register from working
	* as it should.
	*
	* The state controlled by the FFB stencilctl register
	* really gets transferred to the per-buffer instances
	* of the stencilctl register in the 3DRAM chips.
	*
	* The bug is that FFB does not update buffer C correctly,
	* so we have to do it by hand for them.
	*/

	/* This will update buffers A and B. */
	upa_writel(ctx->stencil, &ffb->stencil);
	upa_writel(ctx->stencilctl, &ffb->stencilctl);

	/* Force FFB to use buffer C 3dram regs. */
	upa_writel(0x80000000, &ffb->fbc);
	upa_writel((ctx->stencilctl \| 0x80000),
	&ffb->rawstencilctl);

	/* Now restore the correct FBC controls. */
	upa_writel(ctx->fbc, &ffb->fbc);
	}
	}

	/* Restore the 32x32 area pattern. */
	for (i = 0; i < 32; i++)
	upa_writel(ctx->area_pattern[i], &ffb->pattern[i]);

	/* Finally, stash away the User Constol/Status Register.
	* The only state we really preserve here is the picking
	* control.
	*/
	upa_writel((ctx->ucsr & 0xf0000), &ffb->ucsr);
	}

	#define FFB_UCSR_FB_BUSY 0x01000000
	#define FFB_UCSR_RP_BUSY 0x02000000
	#define FFB_UCSR_ALL_BUSY (FFB_UCSR_RP_BUSY\|FFB_UCSR_FB_BUSY)

	static void FFBWait(ffb_fbcPtr ffb)
	{
	int limit = 100000;

	do {
	u32 regval = upa_readl(&ffb->ucsr);

	if ((regval & FFB_UCSR_ALL_BUSY) == 0)
	break;
	} while (--limit);
	}

	int ffb_driver_context_switch(drm_device_t * dev, int old, int new)
	{
	ffb_dev_priv_t fpriv = (ffb_dev_priv_t ) dev->dev_private;

	#ifdef DRM_DMA_HISTOGRAM
	dev->ctx_start = get_cycles();
	#endif

	DRM_DEBUG("Context switch from %d to %d\n", old, new);

	if (new == dev->last_context \|\| dev->last_context == 0) {
	dev->last_context = new;
	return 0;
	}

	FFBWait(fpriv->regs);
	ffb_save_context(fpriv, old);
	ffb_restore_context(fpriv, old, new);
	FFBWait(fpriv->regs);

	dev->last_context = new;

	return 0;
	}

	int ffb_driver_resctx(struct inode inode, struct file filp, unsigned int cmd,
	unsigned long arg)
	{
	drm_ctx_res_t res;
	drm_ctx_t ctx;
	int i;

	DRM_DEBUG("%d\n", DRM_RESERVED_CONTEXTS);
	if (copy_from_user(&res, (drm_ctx_res_t __user *) arg, sizeof(res)))
	return -EFAULT;
	if (res.count >= DRM_RESERVED_CONTEXTS) {
	memset(&ctx, 0, sizeof(ctx));
	for (i = 0; i < DRM_RESERVED_CONTEXTS; i++) {
	ctx.handle = i;
	if (copy_to_user(&res.contexts[i], &i, sizeof(i)))
	return -EFAULT;
	}
	}
	res.count = DRM_RESERVED_CONTEXTS;
	if (copy_to_user((drm_ctx_res_t __user *) arg, &res, sizeof(res)))
	return -EFAULT;
	return 0;
	}

	int ffb_driver_addctx(struct inode inode, struct file filp, unsigned int cmd,
	unsigned long arg)
	{
	drm_file_t *priv = filp->private_data;
	drm_device_t *dev = priv->dev;
	drm_ctx_t ctx;
	int idx;

	if (copy_from_user(&ctx, (drm_ctx_t __user *) arg, sizeof(ctx)))
	return -EFAULT;
	idx = DRM(alloc_queue) (dev, (ctx.flags & _DRM_CONTEXT_2DONLY));
	if (idx < 0)
	return -ENFILE;

	DRM_DEBUG("%d\n", ctx.handle);
	ctx.handle = idx;
	if (copy_to_user((drm_ctx_t __user *) arg, &ctx, sizeof(ctx)))
	return -EFAULT;
	return 0;
	}

	int ffb_driver_modctx(struct inode inode, struct file filp, unsigned int cmd,
	unsigned long arg)
	{
	drm_file_t *priv = filp->private_data;
	drm_device_t *dev = priv->dev;
	ffb_dev_priv_t fpriv = (ffb_dev_priv_t ) dev->dev_private;
	struct ffb_hw_context *hwctx;
	drm_ctx_t ctx;
	int idx;

	if (copy_from_user(&ctx, (drm_ctx_t __user *) arg, sizeof(ctx)))
	return -EFAULT;

	idx = ctx.handle;
	if (idx <= 0 \|\| idx >= FFB_MAX_CTXS)
	return -EINVAL;

	hwctx = fpriv->hw_state[idx - 1];
	if (hwctx == NULL)
	return -EINVAL;

	if ((ctx.flags & _DRM_CONTEXT_2DONLY) == 0)
	hwctx->is_2d_only = 0;
	else
	hwctx->is_2d_only = 1;

	return 0;
	}

	int ffb_driver_getctx(struct inode inode, struct file filp, unsigned int cmd,
	unsigned long arg)
	{
	drm_file_t *priv = filp->private_data;
	drm_device_t *dev = priv->dev;
	ffb_dev_priv_t fpriv = (ffb_dev_priv_t ) dev->dev_private;
	struct ffb_hw_context *hwctx;
	drm_ctx_t ctx;
	int idx;

	if (copy_from_user(&ctx, (drm_ctx_t __user *) arg, sizeof(ctx)))
	return -EFAULT;

	idx = ctx.handle;
	if (idx <= 0 \|\| idx >= FFB_MAX_CTXS)
	return -EINVAL;

	hwctx = fpriv->hw_state[idx - 1];
	if (hwctx == NULL)
	return -EINVAL;

	if (hwctx->is_2d_only != 0)
	ctx.flags = _DRM_CONTEXT_2DONLY;
	else
	ctx.flags = 0;

	if (copy_to_user((drm_ctx_t __user *) arg, &ctx, sizeof(ctx)))
	return -EFAULT;

	return 0;
	}

	int ffb_driver_switchctx(struct inode inode, struct file filp,
	unsigned int cmd, unsigned long arg)
	{
	drm_file_t *priv = filp->private_data;
	drm_device_t *dev = priv->dev;
	drm_ctx_t ctx;

	if (copy_from_user(&ctx, (drm_ctx_t __user *) arg, sizeof(ctx)))
	return -EFAULT;
	DRM_DEBUG("%d\n", ctx.handle);
	return ffb_driver_context_switch(dev, dev->last_context, ctx.handle);
	}

	int ffb_driver_newctx(struct inode inode, struct file filp, unsigned int cmd,
	unsigned long arg)
	{
	drm_ctx_t ctx;

	if (copy_from_user(&ctx, (drm_ctx_t __user *) arg, sizeof(ctx)))
	return -EFAULT;
	DRM_DEBUG("%d\n", ctx.handle);

	return 0;
	}

	int ffb_driver_rmctx(struct inode inode, struct file filp, unsigned int cmd,
	unsigned long arg)
	{
	drm_ctx_t ctx;
	drm_file_t *priv = filp->private_data;
	drm_device_t *dev = priv->dev;
	ffb_dev_priv_t fpriv = (ffb_dev_priv_t ) dev->dev_private;
	int idx;

	if (copy_from_user(&ctx, (drm_ctx_t __user *) arg, sizeof(ctx)))
	return -EFAULT;
	DRM_DEBUG("%d\n", ctx.handle);

	idx = ctx.handle - 1;
	if (idx < 0 \|\| idx >= FFB_MAX_CTXS)
	return -EINVAL;

	if (fpriv->hw_state[idx] != NULL) {
	kfree(fpriv->hw_state[idx]);
	fpriv->hw_state[idx] = NULL;
	}
	return 0;
	}

	void ffb_set_context_ioctls(void)
	{
	DRM(ioctls)[DRM_IOCTL_NR(DRM_IOCTL_ADD_CTX)].func = ffb_driver_addctx;
	DRM(ioctls)[DRM_IOCTL_NR(DRM_IOCTL_RM_CTX)].func = ffb_driver_rmctx;
	DRM(ioctls)[DRM_IOCTL_NR(DRM_IOCTL_MOD_CTX)].func = ffb_driver_modctx;
	DRM(ioctls)[DRM_IOCTL_NR(DRM_IOCTL_GET_CTX)].func = ffb_driver_getctx;
	DRM(ioctls)[DRM_IOCTL_NR(DRM_IOCTL_SWITCH_CTX)].func =
	ffb_driver_switchctx;
	DRM(ioctls)[DRM_IOCTL_NR(DRM_IOCTL_NEW_CTX)].func = ffb_driver_newctx;
	DRM(ioctls)[DRM_IOCTL_NR(DRM_IOCTL_RES_CTX)].func = ffb_driver_resctx;

	}