Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 739 insertions, 0 deletions

diff --git a/drivers/video/fbdev/matrox/matroxfb_crtc2.c b/drivers/video/fbdev/matrox/matroxfb_crtc2.c
new file mode 100644
index 000000000..7655afa3f
--- /dev/null
+++ b/drivers/video/fbdev/matrox/matroxfb_crtc2.c
@@ -0,0 +1,739 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *
+ * Hardware accelerated Matrox Millennium I, II, Mystique, G100, G200, G400 and G450.
+ *
+ * (c) 1998-2002 Petr Vandrovec <vandrove@vc.cvut.cz>
+ *
+ * Portions Copyright (c) 2001 Matrox Graphics Inc.
+ *
+ * Version: 1.65 2002/08/14
+ *
+ */
+
+#include "matroxfb_maven.h"
+#include "matroxfb_crtc2.h"
+#include "matroxfb_misc.h"
+#include "matroxfb_DAC1064.h"
+#include <linux/matroxfb.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+
+/* **************************************************** */
+
+static int mem = 8192;
+
+module_param(mem, int, 0);
+MODULE_PARM_DESC(mem, "Memory size reserved for dualhead (default=8MB)");
+
+/* **************************************************** */
+
+static int matroxfb_dh_setcolreg(unsigned regno, unsigned red, unsigned green,
+		unsigned blue, unsigned transp, struct fb_info* info) {
+	u_int32_t col;
+#define m2info (container_of(info, struct matroxfb_dh_fb_info, fbcon))
+
+	if (regno >= 16)
+		return 1;
+	if (m2info->fbcon.var.grayscale) {
+		/* gray = 0.30*R + 0.59*G + 0.11*B */
+		red = green = blue = (red * 77 + green * 151 + blue * 28) >> 8;
+	}
+	red = CNVT_TOHW(red, m2info->fbcon.var.red.length);
+	green = CNVT_TOHW(green, m2info->fbcon.var.green.length);
+	blue = CNVT_TOHW(blue, m2info->fbcon.var.blue.length);
+	transp = CNVT_TOHW(transp, m2info->fbcon.var.transp.length);
+
+	col = (red << m2info->fbcon.var.red.offset)     |
+	      (green << m2info->fbcon.var.green.offset) |
+	      (blue << m2info->fbcon.var.blue.offset)   |
+	      (transp << m2info->fbcon.var.transp.offset);
+
+	switch (m2info->fbcon.var.bits_per_pixel) {
+		case 16:
+			m2info->cmap[regno] = col | (col << 16);
+			break;
+		case 32:
+			m2info->cmap[regno] = col;
+			break;
+	}
+	return 0;
+#undef m2info
+}
+
+static void matroxfb_dh_restore(struct matroxfb_dh_fb_info* m2info,
+		struct my_timming* mt,
+		int mode,
+		unsigned int pos) {
+	u_int32_t tmp;
+	u_int32_t datactl;
+	struct matrox_fb_info *minfo = m2info->primary_dev;
+
+	switch (mode) {
+		case 15:
+			tmp = 0x00200000;
+			break;
+		case 16:
+			tmp = 0x00400000;
+			break;
+/*		case 32: */
+		default:
+			tmp = 0x00800000;
+			break;
+	}
+	tmp |= 0x00000001;	/* enable CRTC2 */
+	datactl = 0;
+	if (minfo->outputs[1].src == MATROXFB_SRC_CRTC2) {
+		if (minfo->devflags.g450dac) {
+			tmp |= 0x00000006; /* source from secondary pixel PLL */
+			/* no vidrst when in monitor mode */
+			if (minfo->outputs[1].mode != MATROXFB_OUTPUT_MODE_MONITOR) {
+				tmp |=  0xC0001000; /* Enable H/V vidrst */
+			}
+		} else {
+			tmp |= 0x00000002; /* source from VDOCLK */
+			tmp |= 0xC0000000; /* enable vvidrst & hvidrst */
+			/* MGA TVO is our clock source */
+		}
+	} else if (minfo->outputs[0].src == MATROXFB_SRC_CRTC2) {
+		tmp |= 0x00000004; /* source from pixclock */
+		/* PIXPLL is our clock source */
+	}
+	if (minfo->outputs[0].src == MATROXFB_SRC_CRTC2) {
+		tmp |= 0x00100000;	/* connect CRTC2 to DAC */
+	}
+	if (mt->interlaced) {
+		tmp |= 0x02000000;	/* interlaced, second field is bigger, as G450 apparently ignores it */
+		mt->VDisplay >>= 1;
+		mt->VSyncStart >>= 1;
+		mt->VSyncEnd >>= 1;
+		mt->VTotal >>= 1;
+	}
+	if ((mt->HTotal & 7) == 2) {
+		datactl |= 0x00000010;
+		mt->HTotal &= ~7;
+	}
+	tmp |= 0x10000000;	/* 0x10000000 is VIDRST polarity */
+	mga_outl(0x3C14, ((mt->HDisplay - 8) << 16) | (mt->HTotal - 8));
+	mga_outl(0x3C18, ((mt->HSyncEnd - 8) << 16) | (mt->HSyncStart - 8));
+	mga_outl(0x3C1C, ((mt->VDisplay - 1) << 16) | (mt->VTotal - 1));
+	mga_outl(0x3C20, ((mt->VSyncEnd - 1) << 16) | (mt->VSyncStart - 1));
+	mga_outl(0x3C24, ((mt->VSyncStart) << 16) | (mt->HSyncStart));	/* preload */
+	{
+		u_int32_t linelen = m2info->fbcon.var.xres_virtual * (m2info->fbcon.var.bits_per_pixel >> 3);
+		if (tmp & 0x02000000) {
+			/* field #0 is smaller, so... */
+			mga_outl(0x3C2C, pos);			/* field #1 vmemory start */
+			mga_outl(0x3C28, pos + linelen);	/* field #0 vmemory start */
+			linelen <<= 1;
+			m2info->interlaced = 1;
+		} else {
+			mga_outl(0x3C28, pos);		/* vmemory start */
+			m2info->interlaced = 0;
+		}
+		mga_outl(0x3C40, linelen);
+	}
+	mga_outl(0x3C4C, datactl);	/* data control */
+	if (tmp & 0x02000000) {
+		int i;
+
+		mga_outl(0x3C10, tmp & ~0x02000000);
+		for (i = 0; i < 2; i++) {
+			unsigned int nl;
+			unsigned int lastl = 0;
+
+			while ((nl = mga_inl(0x3C48) & 0xFFF) >= lastl) {
+				lastl = nl;
+			}
+		}
+	}
+	mga_outl(0x3C10, tmp);
+	minfo->hw.crtc2.ctl = tmp;
+
+	tmp = mt->VDisplay << 16;	/* line compare */
+	if (mt->sync & FB_SYNC_HOR_HIGH_ACT)
+		tmp |= 0x00000100;
+	if (mt->sync & FB_SYNC_VERT_HIGH_ACT)
+		tmp |= 0x00000200;
+	mga_outl(0x3C44, tmp);
+}
+
+static void matroxfb_dh_disable(struct matroxfb_dh_fb_info* m2info) {
+	struct matrox_fb_info *minfo = m2info->primary_dev;
+
+	mga_outl(0x3C10, 0x00000004);	/* disable CRTC2, CRTC1->DAC1, PLL as clock source */
+	minfo->hw.crtc2.ctl = 0x00000004;
+}
+
+static void matroxfb_dh_pan_var(struct matroxfb_dh_fb_info* m2info,
+		struct fb_var_screeninfo* var) {
+	unsigned int pos;
+	unsigned int linelen;
+	unsigned int pixelsize;
+	struct matrox_fb_info *minfo = m2info->primary_dev;
+
+	m2info->fbcon.var.xoffset = var->xoffset;
+	m2info->fbcon.var.yoffset = var->yoffset;
+	pixelsize = m2info->fbcon.var.bits_per_pixel >> 3;
+	linelen = m2info->fbcon.var.xres_virtual * pixelsize;
+	pos = m2info->fbcon.var.yoffset * linelen + m2info->fbcon.var.xoffset * pixelsize;
+	pos += m2info->video.offbase;
+	if (m2info->interlaced) {
+		mga_outl(0x3C2C, pos);
+		mga_outl(0x3C28, pos + linelen);
+	} else {
+		mga_outl(0x3C28, pos);
+	}
+}
+
+static int matroxfb_dh_decode_var(struct matroxfb_dh_fb_info* m2info,
+		struct fb_var_screeninfo* var,
+		int *visual,
+		int *video_cmap_len,
+		int *mode) {
+	unsigned int mask;
+	unsigned int memlen;
+	unsigned int vramlen;
+
+	switch (var->bits_per_pixel) {
+		case 16:	mask = 0x1F;
+				break;
+		case 32:	mask = 0x0F;
+				break;
+		default:	return -EINVAL;
+	}
+	vramlen = m2info->video.len_usable;
+	if (var->yres_virtual < var->yres)
+		var->yres_virtual = var->yres;
+	if (var->xres_virtual < var->xres)
+		var->xres_virtual = var->xres;
+	var->xres_virtual = (var->xres_virtual + mask) & ~mask;
+	if (var->yres_virtual > 32767)
+		return -EINVAL;
+	memlen = var->xres_virtual * var->yres_virtual * (var->bits_per_pixel >> 3);
+	if (memlen > vramlen)
+		return -EINVAL;
+	if (var->xoffset + var->xres > var->xres_virtual)
+		var->xoffset = var->xres_virtual - var->xres;
+	if (var->yoffset + var->yres > var->yres_virtual)
+		var->yoffset = var->yres_virtual - var->yres;
+
+	var->xres &= ~7;
+	var->left_margin &= ~7;
+	var->right_margin &= ~7;
+	var->hsync_len &= ~7;
+
+	*mode = var->bits_per_pixel;
+	if (var->bits_per_pixel == 16) {
+		if (var->green.length == 5) {
+			var->red.offset = 10;
+			var->red.length = 5;
+			var->green.offset = 5;
+			var->green.length = 5;
+			var->blue.offset = 0;
+			var->blue.length = 5;
+			var->transp.offset = 15;
+			var->transp.length = 1;
+			*mode = 15;
+		} else {
+			var->red.offset = 11;
+			var->red.length = 5;
+			var->green.offset = 5;
+			var->green.length = 6;
+			var->blue.offset = 0;
+			var->blue.length = 5;
+			var->transp.offset = 0;
+			var->transp.length = 0;
+		}
+	} else {
+			var->red.offset = 16;
+			var->red.length = 8;
+			var->green.offset = 8;
+			var->green.length = 8;
+			var->blue.offset = 0;
+			var->blue.length = 8;
+			var->transp.offset = 24;
+			var->transp.length = 8;
+	}
+	*visual = FB_VISUAL_TRUECOLOR;
+	*video_cmap_len = 16;
+	return 0;
+}
+
+static int matroxfb_dh_open(struct fb_info* info, int user) {
+#define m2info (container_of(info, struct matroxfb_dh_fb_info, fbcon))
+	struct matrox_fb_info *minfo = m2info->primary_dev;
+
+	if (minfo) {
+		int err;
+
+		if (minfo->dead) {
+			return -ENXIO;
+		}
+		err = minfo->fbops.fb_open(&minfo->fbcon, user);
+		if (err) {
+			return err;
+		}
+	}
+	return 0;
+#undef m2info
+}
+
+static int matroxfb_dh_release(struct fb_info* info, int user) {
+#define m2info (container_of(info, struct matroxfb_dh_fb_info, fbcon))
+	int err = 0;
+	struct matrox_fb_info *minfo = m2info->primary_dev;
+
+	if (minfo) {
+		err = minfo->fbops.fb_release(&minfo->fbcon, user);
+	}
+	return err;
+#undef m2info
+}
+
+/*
+ * This function is called before the register_framebuffer so
+ * no locking is needed.
+ */
+static void matroxfb_dh_init_fix(struct matroxfb_dh_fb_info *m2info)
+{
+	struct fb_fix_screeninfo *fix = &m2info->fbcon.fix;
+
+	strcpy(fix->id, "MATROX DH");
+
+	fix->smem_start = m2info->video.base;
+	fix->smem_len = m2info->video.len_usable;
+	fix->ypanstep = 1;
+	fix->ywrapstep = 0;
+	fix->xpanstep = 8;	/* TBD */
+	fix->mmio_start = m2info->mmio.base;
+	fix->mmio_len = m2info->mmio.len;
+	fix->accel = 0;		/* no accel... */
+}
+
+static int matroxfb_dh_check_var(struct fb_var_screeninfo* var, struct fb_info* info) {
+#define m2info (container_of(info, struct matroxfb_dh_fb_info, fbcon))
+	int visual;
+	int cmap_len;
+	int mode;
+
+	return matroxfb_dh_decode_var(m2info, var, &visual, &cmap_len, &mode);
+#undef m2info
+}
+
+static int matroxfb_dh_set_par(struct fb_info* info) {
+#define m2info (container_of(info, struct matroxfb_dh_fb_info, fbcon))
+	int visual;
+	int cmap_len;
+	int mode;
+	int err;
+	struct fb_var_screeninfo* var = &info->var;
+	struct matrox_fb_info *minfo = m2info->primary_dev;
+
+	if ((err = matroxfb_dh_decode_var(m2info, var, &visual, &cmap_len, &mode)) != 0)
+		return err;
+	/* cmap */
+	{
+		m2info->fbcon.screen_base = vaddr_va(m2info->video.vbase);
+		m2info->fbcon.fix.visual = visual;
+		m2info->fbcon.fix.type = FB_TYPE_PACKED_PIXELS;
+		m2info->fbcon.fix.type_aux = 0;
+		m2info->fbcon.fix.line_length = (var->xres_virtual * var->bits_per_pixel) >> 3;
+	}
+	{
+		struct my_timming mt;
+		unsigned int pos;
+		int out;
+		int cnt;
+
+		matroxfb_var2my(&m2info->fbcon.var, &mt);
+		mt.crtc = MATROXFB_SRC_CRTC2;
+		/* CRTC2 delay */
+		mt.delay = 34;
+
+		pos = (m2info->fbcon.var.yoffset * m2info->fbcon.var.xres_virtual + m2info->fbcon.var.xoffset) * m2info->fbcon.var.bits_per_pixel >> 3;
+		pos += m2info->video.offbase;
+		cnt = 0;
+		down_read(&minfo->altout.lock);
+		for (out = 0; out < MATROXFB_MAX_OUTPUTS; out++) {
+			if (minfo->outputs[out].src == MATROXFB_SRC_CRTC2) {
+				cnt++;
+				if (minfo->outputs[out].output->compute) {
+					minfo->outputs[out].output->compute(minfo->outputs[out].data, &mt);
+				}
+			}
+		}
+		minfo->crtc2.pixclock = mt.pixclock;
+		minfo->crtc2.mnp = mt.mnp;
+		up_read(&minfo->altout.lock);
+		if (cnt) {
+			matroxfb_dh_restore(m2info, &mt, mode, pos);
+		} else {
+			matroxfb_dh_disable(m2info);
+		}
+		DAC1064_global_init(minfo);
+		DAC1064_global_restore(minfo);
+		down_read(&minfo->altout.lock);
+		for (out = 0; out < MATROXFB_MAX_OUTPUTS; out++) {
+			if (minfo->outputs[out].src == MATROXFB_SRC_CRTC2 &&
+			    minfo->outputs[out].output->program) {
+				minfo->outputs[out].output->program(minfo->outputs[out].data);
+			}
+		}
+		for (out = 0; out < MATROXFB_MAX_OUTPUTS; out++) {
+			if (minfo->outputs[out].src == MATROXFB_SRC_CRTC2 &&
+			    minfo->outputs[out].output->start) {
+				minfo->outputs[out].output->start(minfo->outputs[out].data);
+			}
+		}
+		up_read(&minfo->altout.lock);
+	}
+	m2info->initialized = 1;
+	return 0;
+#undef m2info
+}
+
+static int matroxfb_dh_pan_display(struct fb_var_screeninfo* var, struct fb_info* info) {
+#define m2info (container_of(info, struct matroxfb_dh_fb_info, fbcon))
+	matroxfb_dh_pan_var(m2info, var);
+	return 0;
+#undef m2info
+}
+
+static int matroxfb_dh_get_vblank(const struct matroxfb_dh_fb_info* m2info, struct fb_vblank* vblank) {
+	struct matrox_fb_info *minfo = m2info->primary_dev;
+
+	matroxfb_enable_irq(minfo, 0);
+	memset(vblank, 0, sizeof(*vblank));
+	vblank->flags = FB_VBLANK_HAVE_VCOUNT | FB_VBLANK_HAVE_VBLANK;
+	/* mask out reserved bits + field number (odd/even) */
+	vblank->vcount = mga_inl(0x3C48) & 0x000007FF;
+	/* compatibility stuff */
+	if (vblank->vcount >= m2info->fbcon.var.yres)
+		vblank->flags |= FB_VBLANK_VBLANKING;
+	if (test_bit(0, &minfo->irq_flags)) {
+                vblank->flags |= FB_VBLANK_HAVE_COUNT;
+                /* Only one writer, aligned int value...
+                   it should work without lock and without atomic_t */
+		vblank->count = minfo->crtc2.vsync.cnt;
+        }
+	return 0;
+}
+
+static int matroxfb_dh_ioctl(struct fb_info *info,
+		unsigned int cmd,
+		unsigned long arg)
+{
+#define m2info (container_of(info, struct matroxfb_dh_fb_info, fbcon))
+	struct matrox_fb_info *minfo = m2info->primary_dev;
+
+	DBG(__func__)
+
+	switch (cmd) {
+		case FBIOGET_VBLANK:
+			{
+				struct fb_vblank vblank;
+				int err;
+
+				err = matroxfb_dh_get_vblank(m2info, &vblank);
+				if (err)
+					return err;
+				if (copy_to_user((void __user *)arg, &vblank, sizeof(vblank)))
+					return -EFAULT;
+				return 0;
+			}
+		case FBIO_WAITFORVSYNC:
+			{
+				u_int32_t crt;
+
+				if (get_user(crt, (u_int32_t __user *)arg))
+					return -EFAULT;
+
+				if (crt != 0)
+					return -ENODEV;
+				return matroxfb_wait_for_sync(minfo, 1);
+			}
+		case MATROXFB_SET_OUTPUT_MODE:
+		case MATROXFB_GET_OUTPUT_MODE:
+		case MATROXFB_GET_ALL_OUTPUTS:
+			{
+				return minfo->fbcon.fbops->fb_ioctl(&minfo->fbcon, cmd, arg);
+			}
+		case MATROXFB_SET_OUTPUT_CONNECTION:
+			{
+				u_int32_t tmp;
+				int out;
+				int changes;
+
+				if (get_user(tmp, (u_int32_t __user *)arg))
+					return -EFAULT;
+				for (out = 0; out < 32; out++) {
+					if (tmp & (1 << out)) {
+						if (out >= MATROXFB_MAX_OUTPUTS)
+							return -ENXIO;
+						if (!minfo->outputs[out].output)
+							return -ENXIO;
+						switch (minfo->outputs[out].src) {
+							case MATROXFB_SRC_NONE:
+							case MATROXFB_SRC_CRTC2:
+								break;
+							default:
+								return -EBUSY;
+						}
+					}
+				}
+				if (minfo->devflags.panellink) {
+					if (tmp & MATROXFB_OUTPUT_CONN_DFP)
+						return -EINVAL;
+					if ((minfo->outputs[2].src == MATROXFB_SRC_CRTC1) && tmp)
+						return -EBUSY;
+				}
+				changes = 0;
+				for (out = 0; out < MATROXFB_MAX_OUTPUTS; out++) {
+					if (tmp & (1 << out)) {
+						if (minfo->outputs[out].src != MATROXFB_SRC_CRTC2) {
+							changes = 1;
+							minfo->outputs[out].src = MATROXFB_SRC_CRTC2;
+						}
+					} else if (minfo->outputs[out].src == MATROXFB_SRC_CRTC2) {
+						changes = 1;
+						minfo->outputs[out].src = MATROXFB_SRC_NONE;
+					}
+				}
+				if (!changes)
+					return 0;
+				matroxfb_dh_set_par(info);
+				return 0;
+			}
+		case MATROXFB_GET_OUTPUT_CONNECTION:
+			{
+				u_int32_t conn = 0;
+				int out;
+
+				for (out = 0; out < MATROXFB_MAX_OUTPUTS; out++) {
+					if (minfo->outputs[out].src == MATROXFB_SRC_CRTC2) {
+						conn |= 1 << out;
+					}
+				}
+				if (put_user(conn, (u_int32_t __user *)arg))
+					return -EFAULT;
+				return 0;
+			}
+		case MATROXFB_GET_AVAILABLE_OUTPUTS:
+			{
+				u_int32_t tmp = 0;
+				int out;
+
+				for (out = 0; out < MATROXFB_MAX_OUTPUTS; out++) {
+					if (minfo->outputs[out].output) {
+						switch (minfo->outputs[out].src) {
+							case MATROXFB_SRC_NONE:
+							case MATROXFB_SRC_CRTC2:
+								tmp |= 1 << out;
+								break;
+						}
+					}
+				}
+				if (minfo->devflags.panellink) {
+					tmp &= ~MATROXFB_OUTPUT_CONN_DFP;
+					if (minfo->outputs[2].src == MATROXFB_SRC_CRTC1) {
+						tmp = 0;
+					}
+				}
+				if (put_user(tmp, (u_int32_t __user *)arg))
+					return -EFAULT;
+				return 0;
+			}
+	}
+	return -ENOTTY;
+#undef m2info
+}
+
+static int matroxfb_dh_blank(int blank, struct fb_info* info) {
+#define m2info (container_of(info, struct matroxfb_dh_fb_info, fbcon))
+	switch (blank) {
+		case 1:
+		case 2:
+		case 3:
+		case 4:
+		default:;
+	}
+	/* do something... */
+	return 0;
+#undef m2info
+}
+
+static const struct fb_ops matroxfb_dh_ops = {
+	.owner =	THIS_MODULE,
+	.fb_open =	matroxfb_dh_open,
+	.fb_release =	matroxfb_dh_release,
+	.fb_check_var =	matroxfb_dh_check_var,
+	.fb_set_par =	matroxfb_dh_set_par,
+	.fb_setcolreg =	matroxfb_dh_setcolreg,
+	.fb_pan_display =matroxfb_dh_pan_display,
+	.fb_blank =	matroxfb_dh_blank,
+	.fb_ioctl =	matroxfb_dh_ioctl,
+	.fb_fillrect =	cfb_fillrect,
+	.fb_copyarea =	cfb_copyarea,
+	.fb_imageblit =	cfb_imageblit,
+};
+
+static struct fb_var_screeninfo matroxfb_dh_defined = {
+		640,480,640,480,/* W,H, virtual W,H */
+		0,0,		/* offset */
+		32,		/* depth */
+		0,		/* gray */
+		{0,0,0},	/* R */
+		{0,0,0},	/* G */
+		{0,0,0},	/* B */
+		{0,0,0},	/* alpha */
+		0,		/* nonstd */
+		FB_ACTIVATE_NOW,
+		-1,-1,		/* display size */
+		0,		/* accel flags */
+		39721L,48L,16L,33L,10L,
+		96L,2,0,	/* no sync info */
+		FB_VMODE_NONINTERLACED,
+};
+
+static int matroxfb_dh_regit(const struct matrox_fb_info *minfo,
+			     struct matroxfb_dh_fb_info *m2info)
+{
+#define minfo (m2info->primary_dev)
+	void* oldcrtc2;
+
+	m2info->fbcon.fbops = &matroxfb_dh_ops;
+	m2info->fbcon.flags = FBINFO_FLAG_DEFAULT;
+	m2info->fbcon.flags |= FBINFO_HWACCEL_XPAN |
+			       FBINFO_HWACCEL_YPAN;
+	m2info->fbcon.pseudo_palette = m2info->cmap;
+	fb_alloc_cmap(&m2info->fbcon.cmap, 256, 1);
+
+	if (mem < 64)
+		mem *= 1024;
+	if (mem < 64*1024)
+		mem *= 1024;
+	mem &= ~0x00000FFF;	/* PAGE_MASK? */
+	if (minfo->video.len_usable + mem <= minfo->video.len)
+		m2info->video.offbase = minfo->video.len - mem;
+	else if (minfo->video.len < mem) {
+		return -ENOMEM;
+	} else { /* check yres on first head... */
+		m2info->video.borrowed = mem;
+		minfo->video.len_usable -= mem;
+		m2info->video.offbase = minfo->video.len_usable;
+	}
+	m2info->video.base = minfo->video.base + m2info->video.offbase;
+	m2info->video.len = m2info->video.len_usable = m2info->video.len_maximum = mem;
+	m2info->video.vbase.vaddr = vaddr_va(minfo->video.vbase) + m2info->video.offbase;
+	m2info->mmio.base = minfo->mmio.base;
+	m2info->mmio.vbase = minfo->mmio.vbase;
+	m2info->mmio.len = minfo->mmio.len;
+
+	matroxfb_dh_init_fix(m2info);
+	if (register_framebuffer(&m2info->fbcon)) {
+		return -ENXIO;
+	}
+	if (!m2info->initialized)
+		fb_set_var(&m2info->fbcon, &matroxfb_dh_defined);
+	down_write(&minfo->crtc2.lock);
+	oldcrtc2 = minfo->crtc2.info;
+	minfo->crtc2.info = m2info;
+	up_write(&minfo->crtc2.lock);
+	if (oldcrtc2) {
+		printk(KERN_ERR "matroxfb_crtc2: Internal consistency check failed: crtc2 already present: %p\n",
+			oldcrtc2);
+	}
+	return 0;
+#undef minfo
+}
+
+/* ************************** */
+
+static int matroxfb_dh_registerfb(struct matroxfb_dh_fb_info* m2info) {
+#define minfo (m2info->primary_dev)
+	if (matroxfb_dh_regit(minfo, m2info)) {
+		printk(KERN_ERR "matroxfb_crtc2: secondary head failed to register\n");
+		return -1;
+	}
+	printk(KERN_INFO "matroxfb_crtc2: secondary head of fb%u was registered as fb%u\n",
+		minfo->fbcon.node, m2info->fbcon.node);
+	m2info->fbcon_registered = 1;
+	return 0;
+#undef minfo
+}
+
+static void matroxfb_dh_deregisterfb(struct matroxfb_dh_fb_info* m2info) {
+#define minfo (m2info->primary_dev)
+	if (m2info->fbcon_registered) {
+		int id;
+		struct matroxfb_dh_fb_info* crtc2;
+
+		down_write(&minfo->crtc2.lock);
+		crtc2 = minfo->crtc2.info;
+		if (crtc2 == m2info)
+			minfo->crtc2.info = NULL;
+		up_write(&minfo->crtc2.lock);
+		if (crtc2 != m2info) {
+			printk(KERN_ERR "matroxfb_crtc2: Internal consistency check failed: crtc2 mismatch at unload: %p != %p\n",
+				crtc2, m2info);
+			printk(KERN_ERR "matroxfb_crtc2: Expect kernel crash after module unload.\n");
+			return;
+		}
+		id = m2info->fbcon.node;
+		unregister_framebuffer(&m2info->fbcon);
+		/* return memory back to primary head */
+		minfo->video.len_usable += m2info->video.borrowed;
+		printk(KERN_INFO "matroxfb_crtc2: fb%u unregistered\n", id);
+		m2info->fbcon_registered = 0;
+	}
+#undef minfo
+}
+
+static void* matroxfb_crtc2_probe(struct matrox_fb_info* minfo) {
+	struct matroxfb_dh_fb_info* m2info;
+
+	/* hardware is CRTC2 incapable... */
+	if (!minfo->devflags.crtc2)
+		return NULL;
+	m2info = kzalloc(sizeof(*m2info), GFP_KERNEL);
+	if (!m2info)
+		return NULL;
+
+	m2info->primary_dev = minfo;
+	if (matroxfb_dh_registerfb(m2info)) {
+		kfree(m2info);
+		printk(KERN_ERR "matroxfb_crtc2: CRTC2 framebuffer failed to register\n");
+		return NULL;
+	}
+	return m2info;
+}
+
+static void matroxfb_crtc2_remove(struct matrox_fb_info* minfo, void* crtc2) {
+	matroxfb_dh_deregisterfb(crtc2);
+	kfree(crtc2);
+}
+
+static struct matroxfb_driver crtc2 = {
+		.name =		"Matrox G400 CRTC2",
+		.probe =	matroxfb_crtc2_probe,
+		.remove =	matroxfb_crtc2_remove };
+
+static int matroxfb_crtc2_init(void) {
+	if (fb_get_options("matrox_crtc2fb", NULL))
+		return -ENODEV;
+
+	matroxfb_register_driver(&crtc2);
+	return 0;
+}
+
+static void matroxfb_crtc2_exit(void) {
+	matroxfb_unregister_driver(&crtc2);
+}
+
+MODULE_AUTHOR("(c) 1999-2002 Petr Vandrovec <vandrove@vc.cvut.cz>");
+MODULE_DESCRIPTION("Matrox G400 CRTC2 driver");
+MODULE_LICENSE("GPL");
+module_init(matroxfb_crtc2_init);
+module_exit(matroxfb_crtc2_exit);
+/* we do not have __setup() yet */