Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 3098 insertions, 0 deletions

diff --git a/drivers/video/atafb.c b/drivers/video/atafb.c
new file mode 100644
index 000000000000..15ec1295bc29
--- /dev/null
+++ b/drivers/video/atafb.c
@@ -0,0 +1,3098 @@
+/*
+ * linux/drivers/video/atafb.c -- Atari builtin chipset frame buffer device
+ *
+ *  Copyright (C) 1994 Martin Schaller & Roman Hodek
+ *  
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file COPYING in the main directory of this archive
+ * for more details.
+ *
+ * History:
+ *   - 03 Jan 95: Original version by Martin Schaller: The TT driver and
+ *                all the device independent stuff
+ *   - 09 Jan 95: Roman: I've added the hardware abstraction (hw_switch)
+ *                and wrote the Falcon, ST(E), and External drivers
+ *                based on the original TT driver.
+ *   - 07 May 95: Martin: Added colormap operations for the external driver
+ *   - 21 May 95: Martin: Added support for overscan
+ *		  Andreas: some bug fixes for this
+ *   -    Jul 95: Guenther Kelleter <guenther@pool.informatik.rwth-aachen.de>:
+ *                Programmable Falcon video modes
+ *                (thanks to Christian Cartus for documentation
+ *                of VIDEL registers).
+ *   - 27 Dec 95: Guenther: Implemented user definable video modes "user[0-7]"
+ *                on minor 24...31. "user0" may be set on commandline by
+ *                "R<x>;<y>;<depth>". (Makes sense only on Falcon)
+ *                Video mode switch on Falcon now done at next VBL interrupt
+ *                to avoid the annoying right shift of the screen.
+ *   - 23 Sep 97: Juergen: added xres_virtual for cards like ProMST
+ *                The external-part is legacy, therefore hardware-specific
+ *                functions like panning/hardwarescrolling/blanking isn't
+ *				  supported.
+ *   - 29 Sep 97: Juergen: added Romans suggestion for pan_display
+ *				  (var->xoffset was changed even if no set_screen_base avail.)
+ *	 - 05 Oct 97: Juergen: extfb (PACKED_PIXEL) is FB_PSEUDOCOLOR 'cause
+ *				  we know how to set the colors
+ *				  ext_*palette: read from ext_colors (former MV300_colors)
+ *							    write to ext_colors and RAMDAC
+ *
+ * To do:
+ *   - For the Falcon it is not possible to set random video modes on
+ *     SM124 and SC/TV, only the bootup resolution is supported.
+ *
+ */
+
+#define ATAFB_TT
+#define ATAFB_STE
+#define ATAFB_EXT
+#define ATAFB_FALCON
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/sched.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/init.h>
+#include <linux/interrupt.h>
+
+#include <asm/setup.h>
+#include <asm/uaccess.h>
+#include <asm/pgtable.h>
+#include <asm/irq.h>
+#include <asm/io.h>
+
+#include <asm/atarihw.h>
+#include <asm/atariints.h>
+#include <asm/atari_stram.h>
+
+#include <linux/fb.h>
+#include <asm/atarikb.h>
+
+#include <video/fbcon.h>
+#include <video/fbcon-cfb8.h>
+#include <video/fbcon-cfb16.h>
+#include <video/fbcon-iplan2p2.h>
+#include <video/fbcon-iplan2p4.h>
+#include <video/fbcon-iplan2p8.h>
+#include <video/fbcon-mfb.h>
+
+
+#define SWITCH_ACIA 0x01		/* modes for switch on OverScan */
+#define SWITCH_SND6 0x40
+#define SWITCH_SND7 0x80
+#define SWITCH_NONE 0x00
+
+
+#define up(x, r) (((x) + (r) - 1) & ~((r)-1))
+
+
+static int default_par=0;	/* default resolution (0=none) */
+
+static unsigned long default_mem_req=0;
+
+static int hwscroll=-1;
+
+static int use_hwscroll = 1;
+
+static int sttt_xres=640,st_yres=400,tt_yres=480;
+static int sttt_xres_virtual=640,sttt_yres_virtual=400;
+static int ovsc_offset=0, ovsc_addlen=0;
+
+static struct atafb_par {
+	void *screen_base;
+	int yres_virtual;
+#if defined ATAFB_TT || defined ATAFB_STE
+	union {
+		struct {
+			int mode;
+			int sync;
+		} tt, st;
+#endif
+#ifdef ATAFB_FALCON
+		struct falcon_hw {
+			/* Here are fields for storing a video mode, as direct
+			 * parameters for the hardware.
+			 */
+			short sync;
+			short line_width;
+			short line_offset;
+			short st_shift;
+			short f_shift;
+			short vid_control;
+			short vid_mode;
+			short xoffset;
+			short hht, hbb, hbe, hdb, hde, hss;
+			short vft, vbb, vbe, vdb, vde, vss;
+			/* auxiliary information */
+			short mono;
+			short ste_mode;
+			short bpp;
+		} falcon;
+#endif
+		/* Nothing needed for external mode */
+	} hw;
+} current_par;
+
+/* Don't calculate an own resolution, and thus don't change the one found when
+ * booting (currently used for the Falcon to keep settings for internal video
+ * hardware extensions (e.g. ScreenBlaster)  */
+static int DontCalcRes = 0; 
+
+#ifdef ATAFB_FALCON
+#define HHT hw.falcon.hht
+#define HBB hw.falcon.hbb
+#define HBE hw.falcon.hbe
+#define HDB hw.falcon.hdb
+#define HDE hw.falcon.hde
+#define HSS hw.falcon.hss
+#define VFT hw.falcon.vft
+#define VBB hw.falcon.vbb
+#define VBE hw.falcon.vbe
+#define VDB hw.falcon.vdb
+#define VDE hw.falcon.vde
+#define VSS hw.falcon.vss
+#define VCO_CLOCK25		0x04
+#define VCO_CSYPOS		0x10
+#define VCO_VSYPOS		0x20
+#define VCO_HSYPOS		0x40
+#define VCO_SHORTOFFS	0x100
+#define VMO_DOUBLE		0x01
+#define VMO_INTER		0x02
+#define VMO_PREMASK		0x0c
+#endif
+
+static struct fb_info fb_info;
+
+static void *screen_base;	/* base address of screen */
+static void *real_screen_base;	/* (only for Overscan) */
+
+static int screen_len;
+
+static int current_par_valid=0; 
+
+static int mono_moni=0;
+
+static struct display disp;
+
+
+#ifdef ATAFB_EXT
+/* external video handling */
+
+static unsigned			external_xres;
+static unsigned			external_xres_virtual;
+static unsigned			external_yres;
+/* not needed - atafb will never support panning/hardwarescroll with external
+ * static unsigned		external_yres_virtual;	
+*/
+
+static unsigned			external_depth;
+static int				external_pmode;
+static void *external_addr = 0;
+static unsigned long	external_len;
+static unsigned long	external_vgaiobase = 0;
+static unsigned int		external_bitspercol = 6;
+
+/* 
+JOE <joe@amber.dinoco.de>: 
+added card type for external driver, is only needed for
+colormap handling.
+*/
+
+enum cardtype { IS_VGA, IS_MV300 };
+static enum cardtype external_card_type = IS_VGA;
+
+/*
+The MV300 mixes the color registers. So we need an array of munged
+indices in order to access the correct reg.
+*/
+static int MV300_reg_1bit[2]={0,1};
+static int MV300_reg_4bit[16]={
+0, 8, 4, 12, 2, 10, 6, 14, 1, 9, 5, 13, 3, 11, 7, 15 };
+static int MV300_reg_8bit[256]={
+0, 128, 64, 192, 32, 160, 96, 224, 16, 144, 80, 208, 48, 176, 112, 240, 
+8, 136, 72, 200, 40, 168, 104, 232, 24, 152, 88, 216, 56, 184, 120, 248, 
+4, 132, 68, 196, 36, 164, 100, 228, 20, 148, 84, 212, 52, 180, 116, 244, 
+12, 140, 76, 204, 44, 172, 108, 236, 28, 156, 92, 220, 60, 188, 124, 252, 
+2, 130, 66, 194, 34, 162, 98, 226, 18, 146, 82, 210, 50, 178, 114, 242, 
+10, 138, 74, 202, 42, 170, 106, 234, 26, 154, 90, 218, 58, 186, 122, 250, 
+6, 134, 70, 198, 38, 166, 102, 230, 22, 150, 86, 214, 54, 182, 118, 246, 
+14, 142, 78, 206, 46, 174, 110, 238, 30, 158, 94, 222, 62, 190, 126, 254, 
+1, 129, 65, 193, 33, 161, 97, 225, 17, 145, 81, 209, 49, 177, 113, 241, 
+9, 137, 73, 201, 41, 169, 105, 233, 25, 153, 89, 217, 57, 185, 121, 249, 
+5, 133, 69, 197, 37, 165, 101, 229, 21, 149, 85, 213, 53, 181, 117, 245, 
+13, 141, 77, 205, 45, 173, 109, 237, 29, 157, 93, 221, 61, 189, 125, 253, 
+3, 131, 67, 195, 35, 163, 99, 227, 19, 147, 83, 211, 51, 179, 115, 243, 
+11, 139, 75, 203, 43, 171, 107, 235, 27, 155, 91, 219, 59, 187, 123, 251, 
+7, 135, 71, 199, 39, 167, 103, 231, 23, 151, 87, 215, 55, 183, 119, 247, 
+15, 143, 79, 207, 47, 175, 111, 239, 31, 159, 95, 223, 63, 191, 127, 255 }; 
+
+static int *MV300_reg = MV300_reg_8bit;
+
+/*
+And on the MV300 it's difficult to read out the hardware palette. So we
+just keep track of the set colors in our own array here, and use that!
+*/
+
+static struct { unsigned char red,green,blue,pad; } ext_color[256];
+#endif /* ATAFB_EXT */
+
+
+static int inverse=0;
+
+extern int fontheight_8x8;
+extern int fontwidth_8x8;
+extern unsigned char fontdata_8x8[];
+
+extern int fontheight_8x16;
+extern int fontwidth_8x16;
+extern unsigned char fontdata_8x16[];
+
+/* ++roman: This structure abstracts from the underlying hardware (ST(e),
+ * TT, or Falcon.
+ *
+ * int (*detect)( void )
+ *   This function should detect the current video mode settings and
+ *   store them in atafb_predefined[0] for later reference by the
+ *   user. Return the index+1 of an equivalent predefined mode or 0
+ *   if there is no such.
+ * 
+ * int (*encode_fix)( struct fb_fix_screeninfo *fix,
+ *                    struct atafb_par *par )
+ *   This function should fill in the 'fix' structure based on the
+ *   values in the 'par' structure.
+ *   
+ * int (*decode_var)( struct fb_var_screeninfo *var,
+ *                    struct atafb_par *par )
+ *   Get the video params out of 'var'. If a value doesn't fit, round
+ *   it up, if it's too big, return EINVAL.
+ *   Round up in the following order: bits_per_pixel, xres, yres, 
+ *   xres_virtual, yres_virtual, xoffset, yoffset, grayscale, bitfields, 
+ *   horizontal timing, vertical timing.
+ *
+ * int (*encode_var)( struct fb_var_screeninfo *var,
+ *                    struct atafb_par *par );
+ *   Fill the 'var' structure based on the values in 'par' and maybe
+ *   other values read out of the hardware.
+ *   
+ * void (*get_par)( struct atafb_par *par )
+ *   Fill the hardware's 'par' structure.
+ *   
+ * void (*set_par)( struct atafb_par *par )
+ *   Set the hardware according to 'par'.
+ *   
+ * int (*getcolreg)( unsigned regno, unsigned *red,
+ *                   unsigned *green, unsigned *blue,
+ *                   unsigned *transp, struct fb_info *info )
+ *   Read a single color register and split it into
+ *   colors/transparent. Return != 0 for invalid regno.
+ *
+ * void (*set_screen_base)(void *s_base)
+ *   Set the base address of the displayed frame buffer. Only called
+ *   if yres_virtual > yres or xres_virtual > xres.
+ *
+ * int (*blank)( int blank_mode )
+ *   Blank the screen if blank_mode!=0, else unblank. If blank==NULL then
+ *   the caller blanks by setting the CLUT to all black. Return 0 if blanking
+ *   succeeded, !=0 if un-/blanking failed due to e.g. a video mode which
+ *   doesn't support it. Implements VESA suspend and powerdown modes on
+ *   hardware that supports disabling hsync/vsync:
+ *       blank_mode==2: suspend vsync, 3:suspend hsync, 4: powerdown.
+ */
+
+static struct fb_hwswitch {
+	int  (*detect)( void );
+	int  (*encode_fix)( struct fb_fix_screeninfo *fix,
+						struct atafb_par *par );
+	int  (*decode_var)( struct fb_var_screeninfo *var,
+						struct atafb_par *par );
+	int  (*encode_var)( struct fb_var_screeninfo *var,
+						struct atafb_par *par );
+	void (*get_par)( struct atafb_par *par );
+	void (*set_par)( struct atafb_par *par );
+	int  (*getcolreg)( unsigned regno, unsigned *red,
+					   unsigned *green, unsigned *blue,
+					   unsigned *transp, struct fb_info *info );
+	void (*set_screen_base)(void *s_base);
+	int  (*blank)( int blank_mode );
+	int  (*pan_display)( struct fb_var_screeninfo *var,
+						 struct atafb_par *par);
+} *fbhw;
+
+static char *autodetect_names[] = {"autodetect", NULL};
+static char *stlow_names[] = {"stlow", NULL};
+static char *stmid_names[] = {"stmid", "default5", NULL};
+static char *sthigh_names[] = {"sthigh", "default4", NULL};
+static char *ttlow_names[] = {"ttlow", NULL};
+static char *ttmid_names[]= {"ttmid", "default1", NULL};
+static char *tthigh_names[]= {"tthigh", "default2", NULL};
+static char *vga2_names[] = {"vga2", NULL};
+static char *vga4_names[] = {"vga4", NULL};
+static char *vga16_names[] = {"vga16", "default3", NULL};
+static char *vga256_names[] = {"vga256", NULL};
+static char *falh2_names[] = {"falh2", NULL};
+static char *falh16_names[] = {"falh16", NULL};
+
+static char **fb_var_names[] = {
+	/* Writing the name arrays directly in this array (via "(char *[]){...}")
+	 * crashes gcc 2.5.8 (sigsegv) if the inner array
+	 * contains more than two items. I've also seen that all elements
+	 * were identical to the last (my cross-gcc) :-(*/
+	autodetect_names,
+	stlow_names,
+	stmid_names,
+	sthigh_names,
+	ttlow_names,
+	ttmid_names,
+	tthigh_names,
+	vga2_names,
+	vga4_names,
+	vga16_names,
+	vga256_names,
+	falh2_names,
+	falh16_names,
+	NULL
+	/* ,NULL */ /* this causes a sigsegv on my gcc-2.5.8 */
+};
+
+static struct fb_var_screeninfo atafb_predefined[] = {
+ 	/*
+ 	 * yres_virtual==0 means use hw-scrolling if possible, else yres
+ 	 */
+ 	{ /* autodetect */
+	  0, 0, 0, 0, 0, 0, 0, 0,   		/* xres-grayscale */
+	  {0, 0, 0}, {0, 0, 0}, {0, 0, 0}, {0, 0, 0}, 	/* red green blue tran*/
+	  0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0 },
+ 	{ /* st low */
+	  320, 200, 320, 0, 0, 0, 4, 0,
+	  {0, 4, 0}, {0, 4, 0}, {0, 4, 0}, {0, 0, 0},
+	  0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0 },
+	{ /* st mid */
+	  640, 200, 640, 0, 0, 0, 2, 0,
+	  {0, 4, 0}, {0, 4, 0}, {0, 4, 0}, {0, 0, 0},
+	  0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0 },
+	{ /* st high */
+	  640, 400, 640, 0, 0, 0, 1, 0,
+	  {0, 4, 0}, {0, 4, 0}, {0, 4, 0}, {0, 0, 0},
+	  0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0 },
+	{ /* tt low */
+	  320, 480, 320, 0, 0, 0, 8, 0,
+	  {0, 4, 0}, {0, 4, 0}, {0, 4, 0}, {0, 0, 0},
+	  0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0 },
+	{ /* tt mid */
+	  640, 480, 640, 0, 0, 0, 4, 0,
+	  {0, 4, 0}, {0, 4, 0}, {0, 4, 0}, {0, 0, 0},
+	  0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0 },
+	{ /* tt high */
+	  1280, 960, 1280, 0, 0, 0, 1, 0,
+	  {0, 4, 0}, {0, 4, 0}, {0, 4, 0}, {0, 0, 0},
+	  0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0 },
+	{ /* vga2 */
+	  640, 480, 640, 0, 0, 0, 1, 0,
+	  {0, 6, 0}, {0, 6, 0}, {0, 6, 0}, {0, 0, 0},
+	  0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0 },
+	{ /* vga4 */
+	  640, 480, 640, 0, 0, 0, 2, 0,
+	  {0, 4, 0}, {0, 4, 0}, {0, 4, 0}, {0, 0, 0},
+	  0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0 },
+	{ /* vga16 */
+	  640, 480, 640, 0, 0, 0, 4, 0,
+	  {0, 6, 0}, {0, 6, 0}, {0, 6, 0}, {0, 0, 0},
+	  0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0 },
+	{ /* vga256 */
+	  640, 480, 640, 0, 0, 0, 8, 0,
+	  {0, 6, 0}, {0, 6, 0}, {0, 6, 0}, {0, 0, 0},
+	  0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0 },
+	{ /* falh2 */
+	  896, 608, 896, 0, 0, 0, 1, 0,
+	  {0, 6, 0}, {0, 6, 0}, {0, 6, 0}, {0, 0, 0},
+	  0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0 },
+	{ /* falh16 */
+	  896, 608, 896, 0, 0, 0, 4, 0,
+	  {0, 6, 0}, {0, 6, 0}, {0, 6, 0}, {0, 0, 0},
+	  0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0 },
+};
+
+static int num_atafb_predefined=ARRAY_SIZE(atafb_predefined);
+
+
+static int
+get_video_mode(char *vname)
+{
+    char ***name_list;
+    char **name;
+    int i;
+    name_list=fb_var_names;
+    for (i = 0 ; i < num_atafb_predefined ; i++) {
+	name=*(name_list++);
+	if (! name || ! *name)
+	    break;
+	while (*name) {
+	    if (! strcmp(vname, *name))
+		return i+1;
+	    name++;
+	}
+    }
+    return 0;
+}
+
+
+
+/* ------------------- TT specific functions ---------------------- */
+
+#ifdef ATAFB_TT
+
+static int tt_encode_fix( struct fb_fix_screeninfo *fix,
+						  struct atafb_par *par )
+
+{
+	int mode;
+
+	strcpy(fix->id,"Atari Builtin");
+	fix->smem_start = (unsigned long)real_screen_base;
+	fix->smem_len = screen_len;
+	fix->type=FB_TYPE_INTERLEAVED_PLANES;
+	fix->type_aux=2;
+	fix->visual=FB_VISUAL_PSEUDOCOLOR;
+	mode = par->hw.tt.mode & TT_SHIFTER_MODEMASK;
+	if (mode == TT_SHIFTER_TTHIGH || mode == TT_SHIFTER_STHIGH) {
+		fix->type=FB_TYPE_PACKED_PIXELS;
+		fix->type_aux=0;
+		if (mode == TT_SHIFTER_TTHIGH)
+			fix->visual=FB_VISUAL_MONO01;
+	}
+	fix->xpanstep=0;
+	fix->ypanstep=1;
+	fix->ywrapstep=0;
+	fix->line_length = 0;
+	fix->accel = FB_ACCEL_ATARIBLITT;
+	return 0;
+}
+
+
+static int tt_decode_var( struct fb_var_screeninfo *var,
+						  struct atafb_par *par )
+{
+	int xres=var->xres;
+	int yres=var->yres;
+	int bpp=var->bits_per_pixel;
+	int linelen;
+	int yres_virtual = var->yres_virtual;
+
+	if (mono_moni) {
+		if (bpp > 1 || xres > sttt_xres*2 || yres >tt_yres*2)
+			return -EINVAL;
+		par->hw.tt.mode=TT_SHIFTER_TTHIGH;
+		xres=sttt_xres*2;
+		yres=tt_yres*2;
+		bpp=1;
+	} else {
+		if (bpp > 8 || xres > sttt_xres || yres > tt_yres)
+			return -EINVAL;
+		if (bpp > 4) {
+			if (xres > sttt_xres/2 || yres > tt_yres)
+				return -EINVAL;
+			par->hw.tt.mode=TT_SHIFTER_TTLOW;
+			xres=sttt_xres/2;
+			yres=tt_yres;
+			bpp=8;
+		}
+		else if (bpp > 2) {
+			if (xres > sttt_xres || yres > tt_yres)
+				return -EINVAL;
+			if (xres > sttt_xres/2 || yres > st_yres/2) {
+				par->hw.tt.mode=TT_SHIFTER_TTMID;
+				xres=sttt_xres;
+				yres=tt_yres;
+				bpp=4;
+			}
+			else {
+				par->hw.tt.mode=TT_SHIFTER_STLOW;
+				xres=sttt_xres/2;
+				yres=st_yres/2;
+				bpp=4;
+			}
+		}
+		else if (bpp > 1) {
+			if (xres > sttt_xres || yres > st_yres/2)
+				return -EINVAL;
+			par->hw.tt.mode=TT_SHIFTER_STMID;
+			xres=sttt_xres;
+			yres=st_yres/2;
+			bpp=2;
+		}
+		else if (var->xres > sttt_xres || var->yres > st_yres) {
+			return -EINVAL;
+		}
+		else {
+			par->hw.tt.mode=TT_SHIFTER_STHIGH;
+			xres=sttt_xres;
+			yres=st_yres;
+			bpp=1;
+		}
+	}
+	if (yres_virtual <= 0)
+		yres_virtual = 0;
+	else if (yres_virtual < yres)
+		yres_virtual = yres;
+	if (var->sync & FB_SYNC_EXT)
+		par->hw.tt.sync=0;
+	else
+		par->hw.tt.sync=1;
+	linelen=xres*bpp/8;
+	if (yres_virtual * linelen > screen_len && screen_len)
+		return -EINVAL;
+	if (yres * linelen > screen_len && screen_len)
+		return -EINVAL;
+	if (var->yoffset + yres > yres_virtual && yres_virtual)
+		return -EINVAL;
+	par->yres_virtual = yres_virtual;
+	par->screen_base = screen_base + var->yoffset * linelen;
+	return 0;
+}
+
+static int tt_encode_var( struct fb_var_screeninfo *var,
+						  struct atafb_par *par )
+{
+	int linelen;
+	memset(var, 0, sizeof(struct fb_var_screeninfo));
+	var->red.offset=0;
+	var->red.length=4;
+	var->red.msb_right=0;
+	var->grayscale=0;
+
+	var->pixclock=31041;
+	var->left_margin=120;		/* these may be incorrect 	*/
+	var->right_margin=100;
+	var->upper_margin=8;
+	var->lower_margin=16;
+	var->hsync_len=140;
+	var->vsync_len=30;
+
+	var->height=-1;
+	var->width=-1;
+
+	if (par->hw.tt.sync & 1)
+		var->sync=0;
+	else
+		var->sync=FB_SYNC_EXT;
+
+	switch (par->hw.tt.mode & TT_SHIFTER_MODEMASK) {
+	case TT_SHIFTER_STLOW:
+		var->xres=sttt_xres/2;
+		var->xres_virtual=sttt_xres_virtual/2;
+		var->yres=st_yres/2;
+		var->bits_per_pixel=4;
+		break;
+	case TT_SHIFTER_STMID:
+		var->xres=sttt_xres;
+		var->xres_virtual=sttt_xres_virtual;
+		var->yres=st_yres/2;
+		var->bits_per_pixel=2;
+		break;
+	case TT_SHIFTER_STHIGH:
+		var->xres=sttt_xres;
+		var->xres_virtual=sttt_xres_virtual;
+		var->yres=st_yres;
+		var->bits_per_pixel=1;
+		break;
+	case TT_SHIFTER_TTLOW:
+		var->xres=sttt_xres/2;
+		var->xres_virtual=sttt_xres_virtual/2;
+		var->yres=tt_yres;
+		var->bits_per_pixel=8;
+		break;
+	case TT_SHIFTER_TTMID:
+		var->xres=sttt_xres;
+		var->xres_virtual=sttt_xres_virtual;
+		var->yres=tt_yres;
+		var->bits_per_pixel=4;
+		break;
+	case TT_SHIFTER_TTHIGH:
+		var->red.length=0;
+		var->xres=sttt_xres*2;
+		var->xres_virtual=sttt_xres_virtual*2;
+		var->yres=tt_yres*2;
+		var->bits_per_pixel=1;
+		break;
+	}		
+	var->blue=var->green=var->red;
+	var->transp.offset=0;
+	var->transp.length=0;
+	var->transp.msb_right=0;
+	linelen=var->xres_virtual * var->bits_per_pixel / 8;
+	if (! use_hwscroll)
+		var->yres_virtual=var->yres;
+	else if (screen_len) {
+		if (par->yres_virtual)
+			var->yres_virtual = par->yres_virtual;
+		else
+			/* yres_virtual==0 means use maximum */
+			var->yres_virtual = screen_len / linelen;
+	} else {
+		if (hwscroll < 0)
+			var->yres_virtual = 2 * var->yres;
+		else
+			var->yres_virtual=var->yres+hwscroll * 16;
+	}
+	var->xoffset=0;
+	if (screen_base)
+		var->yoffset=(par->screen_base - screen_base)/linelen;
+	else
+		var->yoffset=0;
+	var->nonstd=0;
+	var->activate=0;
+	var->vmode=FB_VMODE_NONINTERLACED;
+	return 0;
+}
+
+
+static void tt_get_par( struct atafb_par *par )
+{
+	unsigned long addr;
+	par->hw.tt.mode=shifter_tt.tt_shiftmode;
+	par->hw.tt.sync=shifter.syncmode;
+	addr = ((shifter.bas_hi & 0xff) << 16) |
+	       ((shifter.bas_md & 0xff) << 8)  |
+	       ((shifter.bas_lo & 0xff));
+	par->screen_base = phys_to_virt(addr);
+}
+
+static void tt_set_par( struct atafb_par *par )
+{
+	shifter_tt.tt_shiftmode=par->hw.tt.mode;
+	shifter.syncmode=par->hw.tt.sync;
+	/* only set screen_base if really necessary */
+	if (current_par.screen_base != par->screen_base)
+		fbhw->set_screen_base(par->screen_base);
+}
+
+
+static int tt_getcolreg(unsigned regno, unsigned *red,
+			unsigned *green, unsigned *blue,
+			unsigned *transp, struct fb_info *info)
+{
+	int t, col;
+
+	if ((shifter_tt.tt_shiftmode & TT_SHIFTER_MODEMASK) == TT_SHIFTER_STHIGH)
+		regno += 254;
+	if (regno > 255)
+		return 1;
+	t = tt_palette[regno];
+	col = t & 15;
+	col |= col << 4;
+	col |= col << 8;
+	*blue = col;
+	col = (t >> 4) & 15;
+	col |= col << 4;
+	col |= col << 8;
+	*green = col;
+	col = (t >> 8) & 15;
+	col |= col << 4;
+	col |= col << 8;
+	*red = col;
+	*transp = 0;
+	return 0;
+}
+
+
+static int tt_setcolreg(unsigned regno, unsigned red,
+			unsigned green, unsigned blue,
+			unsigned transp, struct fb_info *info)
+{
+	if ((shifter_tt.tt_shiftmode & TT_SHIFTER_MODEMASK) == TT_SHIFTER_STHIGH)
+		regno += 254;
+	if (regno > 255)
+		return 1;
+	tt_palette[regno] = (((red >> 12) << 8) | ((green >> 12) << 4) |
+			     (blue >> 12));
+	if ((shifter_tt.tt_shiftmode & TT_SHIFTER_MODEMASK) ==
+		TT_SHIFTER_STHIGH && regno == 254)
+		tt_palette[0] = 0;
+	return 0;
+}
+
+						  
+static int tt_detect( void )
+
+{	struct atafb_par par;
+
+	/* Determine the connected monitor: The DMA sound must be
+	 * disabled before reading the MFP GPIP, because the Sound
+	 * Done Signal and the Monochrome Detect are XORed together!
+	 *
+	 * Even on a TT, we should look if there is a DMA sound. It was
+	 * announced that the Eagle is TT compatible, but only the PCM is
+	 * missing...
+	 */
+	if (ATARIHW_PRESENT(PCM_8BIT)) { 
+		tt_dmasnd.ctrl = DMASND_CTRL_OFF;
+		udelay(20);	/* wait a while for things to settle down */
+	}
+	mono_moni = (mfp.par_dt_reg & 0x80) == 0;
+
+	tt_get_par(&par);
+	tt_encode_var(&atafb_predefined[0], &par);
+
+	return 1;
+}
+
+#endif /* ATAFB_TT */
+
+/* ------------------- Falcon specific functions ---------------------- */
+
+#ifdef ATAFB_FALCON
+
+static int mon_type;		/* Falcon connected monitor */
+static int f030_bus_width;	/* Falcon ram bus width (for vid_control) */
+#define F_MON_SM	0
+#define F_MON_SC	1
+#define F_MON_VGA	2
+#define F_MON_TV	3
+
+static struct pixel_clock {
+	unsigned long f;	/* f/[Hz] */
+	unsigned long t;	/* t/[ps] (=1/f) */
+	int right, hsync, left;	/* standard timing in clock cycles, not pixel */
+		/* hsync initialized in falcon_detect() */
+	int sync_mask;		/* or-mask for hw.falcon.sync to set this clock */
+	int control_mask;	/* ditto, for hw.falcon.vid_control */
+}
+f25  = {25175000, 39721, 18, 0, 42, 0x0, VCO_CLOCK25},
+f32  = {32000000, 31250, 18, 0, 42, 0x0, 0},
+fext = {       0,     0, 18, 0, 42, 0x1, 0};
+
+/* VIDEL-prescale values [mon_type][pixel_length from VCO] */
+static int vdl_prescale[4][3] = {{4,2,1}, {4,2,1}, {4,2,2}, {4,2,1}};
+
+/* Default hsync timing [mon_type] in picoseconds */
+static long h_syncs[4] = {3000000, 4875000, 4000000, 4875000};
+
+#ifdef FBCON_HAS_CFB16
+static u16 fbcon_cfb16_cmap[16];
+#endif
+
+static inline int hxx_prescale(struct falcon_hw *hw)
+{
+	return hw->ste_mode ? 16 :
+		   vdl_prescale[mon_type][hw->vid_mode >> 2 & 0x3];
+}
+
+static int falcon_encode_fix( struct fb_fix_screeninfo *fix,
+							  struct atafb_par *par )
+{
+	strcpy(fix->id, "Atari Builtin");
+	fix->smem_start = (unsigned long)real_screen_base;
+	fix->smem_len = screen_len;
+	fix->type = FB_TYPE_INTERLEAVED_PLANES;
+	fix->type_aux = 2;
+	fix->visual = FB_VISUAL_PSEUDOCOLOR;
+	fix->xpanstep = 1;
+	fix->ypanstep = 1;
+	fix->ywrapstep = 0;
+	if (par->hw.falcon.mono) {
+		fix->type = FB_TYPE_PACKED_PIXELS;
+		fix->type_aux = 0;
+		/* no smooth scrolling with longword aligned video mem */
+		fix->xpanstep = 32;
+	}
+	else if (par->hw.falcon.f_shift & 0x100) {
+		fix->type = FB_TYPE_PACKED_PIXELS;
+		fix->type_aux = 0;
+		/* Is this ok or should it be DIRECTCOLOR? */
+		fix->visual = FB_VISUAL_TRUECOLOR;
+		fix->xpanstep = 2;
+	}
+	fix->line_length = 0;
+	fix->accel = FB_ACCEL_ATARIBLITT;
+	return 0;
+}
+
+
+static int falcon_decode_var( struct fb_var_screeninfo *var,
+							  struct atafb_par *par )
+{
+	int bpp = var->bits_per_pixel;
+	int xres = var->xres;
+	int yres = var->yres;
+	int xres_virtual = var->xres_virtual;
+	int yres_virtual = var->yres_virtual;
+	int left_margin, right_margin, hsync_len;
+	int upper_margin, lower_margin, vsync_len;
+	int linelen;
+	int interlace = 0, doubleline = 0;
+	struct pixel_clock *pclock;
+	int plen; /* width of pixel in clock cycles */
+	int xstretch;
+	int prescale;
+	int longoffset = 0;
+	int hfreq, vfreq;
+
+/*
+	Get the video params out of 'var'. If a value doesn't fit, round
+	it up, if it's too big, return EINVAL.
+	Round up in the following order: bits_per_pixel, xres, yres, 
+	xres_virtual, yres_virtual, xoffset, yoffset, grayscale, bitfields, 
+	horizontal timing, vertical timing.
+
+	There is a maximum of screen resolution determined by pixelclock
+	and minimum frame rate -- (X+hmarg.)*(Y+vmarg.)*vfmin <= pixelclock.
+	In interlace mode this is     "     *    "     *vfmin <= pixelclock.
+	Additional constraints: hfreq.
+	Frequency range for multisync monitors is given via command line.
+	For TV and SM124 both frequencies are fixed.
+
+	X % 16 == 0 to fit 8x?? font (except 1 bitplane modes must use X%32==0)
+	Y % 16 == 0 to fit 8x16 font
+	Y % 8 == 0 if Y<400
+
+	Currently interlace and doubleline mode in var are ignored. 
+	On SM124 and TV only the standard resolutions can be used.
+*/
+
+	/* Reject uninitialized mode */
+	if (!xres || !yres || !bpp)
+		return -EINVAL;
+
+	if (mon_type == F_MON_SM && bpp != 1) {
+		return -EINVAL;
+	}
+	else if (bpp <= 1) {
+		bpp = 1;
+		par->hw.falcon.f_shift = 0x400;
+		par->hw.falcon.st_shift = 0x200;
+	}
+	else if (bpp <= 2) {
+		bpp = 2;
+		par->hw.falcon.f_shift = 0x000;
+		par->hw.falcon.st_shift = 0x100;
+	}
+	else if (bpp <= 4) {
+		bpp = 4;
+		par->hw.falcon.f_shift = 0x000;
+		par->hw.falcon.st_shift = 0x000;
+	}
+	else if (bpp <= 8) {
+		bpp = 8;
+		par->hw.falcon.f_shift = 0x010;
+	}
+	else if (bpp <= 16) {
+		bpp = 16; /* packed pixel mode */
+		par->hw.falcon.f_shift = 0x100; /* hicolor, no overlay */
+	}
+	else
+		return -EINVAL;
+	par->hw.falcon.bpp = bpp;
+
+	if (mon_type == F_MON_SM || DontCalcRes) {
+		/* Skip all calculations. VGA/TV/SC1224 only supported. */
+		struct fb_var_screeninfo *myvar = &atafb_predefined[0];
+		
+		if (bpp > myvar->bits_per_pixel ||
+			var->xres > myvar->xres ||
+			var->yres > myvar->yres)
+			return -EINVAL;
+		fbhw->get_par(par);	/* Current par will be new par */
+		goto set_screen_base;	/* Don't forget this */
+	}
+
+	/* Only some fixed resolutions < 640x400 */
+	if (xres <= 320)
+		xres = 320;
+	else if (xres <= 640 && bpp != 16)
+		xres = 640;
+	if (yres <= 200)
+		yres = 200;
+	else if (yres <= 240)
+		yres = 240;
+	else if (yres <= 400)
+		yres = 400;
+
+	/* 2 planes must use STE compatibility mode */
+	par->hw.falcon.ste_mode = bpp==2;
+	par->hw.falcon.mono = bpp==1;
+
+	/* Total and visible scanline length must be a multiple of one longword,
+	 * this and the console fontwidth yields the alignment for xres and
+	 * xres_virtual.
+	 * TODO: this way "odd" fontheights are not supported
+	 *
+	 * Special case in STE mode: blank and graphic positions don't align,
+	 * avoid trash at right margin
+	 */
+	if (par->hw.falcon.ste_mode)
+		xres = (xres + 63) & ~63;
+	else if (bpp == 1)
+		xres = (xres + 31) & ~31;
+	else
+		xres = (xres + 15) & ~15;
+	if (yres >= 400)
+		yres = (yres + 15) & ~15;
+	else
+		yres = (yres + 7) & ~7;
+
+	if (xres_virtual < xres)
+		xres_virtual = xres;
+	else if (bpp == 1)
+		xres_virtual = (xres_virtual + 31) & ~31;
+	else
+		xres_virtual = (xres_virtual + 15) & ~15;
+
+	if (yres_virtual <= 0)
+		yres_virtual = 0;
+	else if (yres_virtual < yres)
+		yres_virtual = yres;
+
+	/* backward bug-compatibility */
+	if (var->pixclock > 1)
+		var->pixclock -= 1;
+
+	par->hw.falcon.line_width = bpp * xres / 16;
+	par->hw.falcon.line_offset = bpp * (xres_virtual - xres) / 16;
+
+	/* single or double pixel width */
+	xstretch = (xres < 640) ? 2 : 1;
+
+#if 0 /* SM124 supports only 640x400, this is rejected above */
+	if (mon_type == F_MON_SM) {
+		if (xres != 640 && yres != 400)
+			return -EINVAL;
+		plen = 1;
+		pclock = &f32;
+		/* SM124-mode is special */
+		par->hw.falcon.ste_mode = 1;
+		par->hw.falcon.f_shift = 0x000;
+		par->hw.falcon.st_shift = 0x200;
+		left_margin = hsync_len = 128 / plen;
+		right_margin = 0;
+		/* TODO set all margins */
+	}
+	else
+#endif
+	if (mon_type == F_MON_SC || mon_type == F_MON_TV) {
+		plen = 2 * xstretch;
+		if (var->pixclock > f32.t * plen)
+			return -EINVAL;
+		pclock = &f32;
+		if (yres > 240)
+			interlace = 1;
+		if (var->pixclock == 0) {
+			/* set some minimal margins which center the screen */
+			left_margin = 32;
+			right_margin = 18;
+			hsync_len = pclock->hsync / plen;
+			upper_margin = 31;
+			lower_margin = 14;
+			vsync_len = interlace ? 3 : 4;
+		} else {
+			left_margin = var->left_margin;
+			right_margin = var->right_margin;
+			hsync_len = var->hsync_len;
+			upper_margin = var->upper_margin;
+			lower_margin = var->lower_margin;
+			vsync_len = var->vsync_len;
+			if (var->vmode & FB_VMODE_INTERLACED) {
+				upper_margin = (upper_margin + 1) / 2;
+				lower_margin = (lower_margin + 1) / 2;
+				vsync_len = (vsync_len + 1) / 2;
+			} else if (var->vmode & FB_VMODE_DOUBLE) {
+				upper_margin *= 2;
+				lower_margin *= 2;
+				vsync_len *= 2;
+			}
+		}
+	}
+	else
+	{	/* F_MON_VGA */
+		if (bpp == 16)
+			xstretch = 2; /* Double pixel width only for hicolor */
+		/* Default values are used for vert./hor. timing if no pixelclock given. */
+		if (var->pixclock == 0) {
+			int linesize;
+
+			/* Choose master pixelclock depending on hor. timing */
+			plen = 1 * xstretch;
+			if ((plen * xres + f25.right+f25.hsync+f25.left) *
+			    fb_info.monspecs.hfmin < f25.f)
+				pclock = &f25;
+			else if ((plen * xres + f32.right+f32.hsync+f32.left) * 
+			    fb_info.monspecs.hfmin < f32.f)
+				pclock = &f32;
+			else if ((plen * xres + fext.right+fext.hsync+fext.left) * 
+			    fb_info.monspecs.hfmin < fext.f
+			         && fext.f)
+				pclock = &fext;
+			else
+				return -EINVAL;
+
+			left_margin = pclock->left / plen;
+			right_margin = pclock->right / plen;
+			hsync_len = pclock->hsync / plen;
+			linesize = left_margin + xres + right_margin + hsync_len;
+			upper_margin = 31;
+			lower_margin = 11;
+			vsync_len = 3;
+		}
+		else {
+			/* Choose largest pixelclock <= wanted clock */
+			int i;
+			unsigned long pcl = ULONG_MAX;
+			pclock = 0;
+			for (i=1; i <= 4; i *= 2) {
+				if (f25.t*i >= var->pixclock && f25.t*i < pcl) {
+					pcl = f25.t * i;
+					pclock = &f25;
+				}
+				if (f32.t*i >= var->pixclock && f32.t*i < pcl) {
+					pcl = f32.t * i;
+					pclock = &f32;
+				}
+				if (fext.t && fext.t*i >= var->pixclock && fext.t*i < pcl) {
+					pcl = fext.t * i;
+					pclock = &fext;
+				}
+			}
+			if (!pclock)
+				return -EINVAL;
+			plen = pcl / pclock->t;
+
+			left_margin = var->left_margin;
+			right_margin = var->right_margin;
+			hsync_len = var->hsync_len;
+			upper_margin = var->upper_margin;
+			lower_margin = var->lower_margin;
+			vsync_len = var->vsync_len;
+			/* Internal unit is [single lines per (half-)frame] */
+			if (var->vmode & FB_VMODE_INTERLACED) {
+				/* # lines in half frame */
+				/* External unit is [lines per full frame] */
+				upper_margin = (upper_margin + 1) / 2;
+				lower_margin = (lower_margin + 1) / 2;
+				vsync_len = (vsync_len + 1) / 2;
+			}
+			else if (var->vmode & FB_VMODE_DOUBLE) {
+				/* External unit is [double lines per frame] */
+				upper_margin *= 2;
+				lower_margin *= 2;
+				vsync_len *= 2;
+			}
+		}
+		if (pclock == &fext)
+			longoffset = 1; /* VIDEL doesn't synchronize on short offset */
+	}
+	/* Is video bus bandwidth (32MB/s) too low for this resolution? */
+	/* this is definitely wrong if bus clock != 32MHz */
+	if (pclock->f / plen / 8 * bpp > 32000000L)
+		return -EINVAL;
+
+	if (vsync_len < 1)
+		vsync_len = 1;
+
+	/* include sync lengths in right/lower margin for all calculations */
+	right_margin += hsync_len;
+	lower_margin += vsync_len;
+
+	/* ! In all calculations of margins we use # of lines in half frame
+	 * (which is a full frame in non-interlace mode), so we can switch
+	 * between interlace and non-interlace without messing around
+	 * with these.
+	 */
+  again:
+	/* Set base_offset 128 and video bus width */
+	par->hw.falcon.vid_control = mon_type | f030_bus_width;
+	if (!longoffset)
+		par->hw.falcon.vid_control |= VCO_SHORTOFFS;	/* base_offset 64 */
+	if (var->sync & FB_SYNC_HOR_HIGH_ACT)
+		par->hw.falcon.vid_control |= VCO_HSYPOS;
+	if (var->sync & FB_SYNC_VERT_HIGH_ACT)
+		par->hw.falcon.vid_control |= VCO_VSYPOS;
+	/* Pixelclock */
+	par->hw.falcon.vid_control |= pclock->control_mask;
+	/* External or internal clock */
+	par->hw.falcon.sync = pclock->sync_mask | 0x2;
+	/* Pixellength and prescale */
+	par->hw.falcon.vid_mode = (2/plen) << 2;
+	if (doubleline)
+		par->hw.falcon.vid_mode |= VMO_DOUBLE;
+	if (interlace)
+		par->hw.falcon.vid_mode |= VMO_INTER;
+
+	/*********************
+	Horizontal timing: unit = [master clock cycles]
+	unit of hxx-registers: [master clock cycles * prescale]
+	Hxx-registers are 9 bit wide
+
+	1 line = ((hht + 2) * 2 * prescale) clock cycles
+
+	graphic output = hdb & 0x200 ?
+	       ((hht+2)*2 - hdb + hde) * prescale - hdboff + hdeoff:
+	       ( hht + 2  - hdb + hde) * prescale - hdboff + hdeoff
+	(this must be a multiple of plen*128/bpp, on VGA pixels
+	 to the right may be cut off with a bigger right margin)
+
+	start of graphics relative to start of 1st halfline = hdb & 0x200 ?
+	       (hdb - hht - 2) * prescale + hdboff :
+	       hdb * prescale + hdboff
+
+	end of graphics relative to start of 1st halfline =
+	       (hde + hht + 2) * prescale + hdeoff
+	*********************/
+	/* Calculate VIDEL registers */
+	{
+	int hdb_off, hde_off, base_off;
+	int gstart, gend1, gend2, align;
+
+	prescale = hxx_prescale(&par->hw.falcon);
+	base_off = par->hw.falcon.vid_control & VCO_SHORTOFFS ? 64 : 128;
+
+	/* Offsets depend on video mode */
+	/* Offsets are in clock cycles, divide by prescale to
+	 * calculate hd[be]-registers
+	 */
+	if (par->hw.falcon.f_shift & 0x100) {
+		align = 1;
+		hde_off = 0;
+		hdb_off = (base_off + 16 * plen) + prescale;
+	}
+	else {
+		align = 128 / bpp;
+		hde_off = ((128 / bpp + 2) * plen);
+		if (par->hw.falcon.ste_mode)
+			hdb_off = (64 + base_off + (128 / bpp + 2) * plen) + prescale;
+		else
+			hdb_off = (base_off + (128 / bpp + 18) * plen) + prescale;
+	}
+
+	gstart = (prescale/2 + plen * left_margin) / prescale;
+	/* gend1 is for hde (gend-gstart multiple of align), shifter's xres */
+	gend1 = gstart + ((xres + align-1) / align)*align * plen / prescale;
+	/* gend2 is for hbb, visible xres (rest to gend1 is cut off by hblank) */
+	gend2 = gstart + xres * plen / prescale;
+	par->HHT = plen * (left_margin + xres + right_margin) /
+			   (2 * prescale) - 2;
+/*	par->HHT = (gend2 + plen * right_margin / prescale) / 2 - 2;*/
+
+	par->HDB = gstart - hdb_off/prescale;
+	par->HBE = gstart;
+	if (par->HDB < 0) par->HDB += par->HHT + 2 + 0x200;
+	par->HDE = gend1 - par->HHT - 2 - hde_off/prescale;
+	par->HBB = gend2 - par->HHT - 2;
+#if 0
+	/* One more Videl constraint: data fetch of two lines must not overlap */
+	if ((par->HDB & 0x200)  &&  (par->HDB & ~0x200) - par->HDE <= 5) {
+		/* if this happens increase margins, decrease hfreq. */
+	}
+#endif
+	if (hde_off % prescale)
+		par->HBB++;		/* compensate for non matching hde and hbb */
+	par->HSS = par->HHT + 2 - plen * hsync_len / prescale;
+	if (par->HSS < par->HBB)
+		par->HSS = par->HBB;
+	}
+
+	/*  check hor. frequency */
+	hfreq = pclock->f / ((par->HHT+2)*prescale*2);
+	if (hfreq > fb_info.monspecs.hfmax && mon_type!=F_MON_VGA) {
+		/* ++guenther:   ^^^^^^^^^^^^^^^^^^^ can't remember why I did this */
+		/* Too high -> enlarge margin */
+		left_margin += 1;
+		right_margin += 1;
+		goto again;
+	}
+	if (hfreq > fb_info.monspecs.hfmax || hfreq < fb_info.monspecs.hfmin)
+		return -EINVAL;
+
+	/* Vxx-registers */
+	/* All Vxx must be odd in non-interlace, since frame starts in the middle
+	 * of the first displayed line!
+	 * One frame consists of VFT+1 half lines. VFT+1 must be even in
+	 * non-interlace, odd in interlace mode for synchronisation.
+	 * Vxx-registers are 11 bit wide
+	 */
+	par->VBE = (upper_margin * 2 + 1); /* must begin on odd halfline */
+	par->VDB = par->VBE;
+	par->VDE = yres;
+	if (!interlace) par->VDE <<= 1;
+	if (doubleline) par->VDE <<= 1;  /* VDE now half lines per (half-)frame */
+	par->VDE += par->VDB;
+	par->VBB = par->VDE;
+	par->VFT = par->VBB + (lower_margin * 2 - 1) - 1;
+	par->VSS = par->VFT+1 - (vsync_len * 2 - 1);
+	/* vbb,vss,vft must be even in interlace mode */
+	if (interlace) {
+		par->VBB++;
+		par->VSS++;
+		par->VFT++;
+	}
+
+	/* V-frequency check, hope I didn't create any loop here. */
+	/* Interlace and doubleline are mutually exclusive. */
+	vfreq = (hfreq * 2) / (par->VFT + 1);
+	if      (vfreq > fb_info.monspecs.vfmax && !doubleline && !interlace) {
+		/* Too high -> try again with doubleline */
+		doubleline = 1;
+		goto again;
+	}
+	else if (vfreq < fb_info.monspecs.vfmin && !interlace && !doubleline) {
+		/* Too low -> try again with interlace */
+		interlace = 1;
+		goto again;
+	}
+	else if (vfreq < fb_info.monspecs.vfmin && doubleline) {
+		/* Doubleline too low -> clear doubleline and enlarge margins */
+		int lines;
+		doubleline = 0;
+		for (lines=0;
+		     (hfreq*2)/(par->VFT+1+4*lines-2*yres)>fb_info.monspecs.vfmax;
+		     lines++)
+			;
+		upper_margin += lines;
+		lower_margin += lines;
+		goto again;
+	}
+	else if (vfreq > fb_info.monspecs.vfmax && doubleline) {
+		/* Doubleline too high -> enlarge margins */
+		int lines;
+		for (lines=0;
+		     (hfreq*2)/(par->VFT+1+4*lines)>fb_info.monspecs.vfmax;
+		     lines+=2)
+			;
+		upper_margin += lines;
+		lower_margin += lines;
+		goto again;
+	}
+	else if (vfreq > fb_info.monspecs.vfmax && interlace) {
+		/* Interlace, too high -> enlarge margins */
+		int lines;
+		for (lines=0;
+		     (hfreq*2)/(par->VFT+1+4*lines)>fb_info.monspecs.vfmax;
+		     lines++)
+			;
+		upper_margin += lines;
+		lower_margin += lines;
+		goto again;
+	}
+	else if (vfreq < fb_info.monspecs.vfmin ||
+		 vfreq > fb_info.monspecs.vfmax)
+		return -EINVAL;
+
+  set_screen_base:
+	linelen = xres_virtual * bpp / 8;
+	if (yres_virtual * linelen > screen_len && screen_len)
+		return -EINVAL;
+	if (yres * linelen > screen_len && screen_len)
+		return -EINVAL;
+	if (var->yoffset + yres > yres_virtual && yres_virtual)
+		return -EINVAL;
+	par->yres_virtual = yres_virtual;
+	par->screen_base = screen_base + var->yoffset * linelen;
+	par->hw.falcon.xoffset = 0;
+
+	return 0;
+}
+
+static int falcon_encode_var( struct fb_var_screeninfo *var,
+							  struct atafb_par *par )
+{
+/* !!! only for VGA !!! */
+	int linelen;
+	int prescale, plen;
+	int hdb_off, hde_off, base_off;
+	struct falcon_hw *hw = &par->hw.falcon;
+
+	memset(var, 0, sizeof(struct fb_var_screeninfo));
+	/* possible frequencies: 25.175 or 32MHz */
+	var->pixclock = hw->sync & 0x1 ? fext.t :
+	                hw->vid_control & VCO_CLOCK25 ? f25.t : f32.t;
+
+	var->height=-1;
+	var->width=-1;
+
+	var->sync=0;
+	if (hw->vid_control & VCO_HSYPOS)
+		var->sync |= FB_SYNC_HOR_HIGH_ACT;
+	if (hw->vid_control & VCO_VSYPOS)
+		var->sync |= FB_SYNC_VERT_HIGH_ACT;
+
+	var->vmode = FB_VMODE_NONINTERLACED;
+	if (hw->vid_mode & VMO_INTER)
+		var->vmode |= FB_VMODE_INTERLACED;
+	if (hw->vid_mode & VMO_DOUBLE)
+		var->vmode |= FB_VMODE_DOUBLE;
+	
+	/* visible y resolution:
+	 * Graphics display starts at line VDB and ends at line
+	 * VDE. If interlace mode off unit of VC-registers is
+	 * half lines, else lines.
+	 */
+	var->yres = hw->vde - hw->vdb;
+	if (!(var->vmode & FB_VMODE_INTERLACED))
+		var->yres >>= 1;
+	if (var->vmode & FB_VMODE_DOUBLE)
+		var->yres >>= 1;
+
+	/* to get bpp, we must examine f_shift and st_shift.
+	 * f_shift is valid if any of bits no. 10, 8 or 4
+	 * is set. Priority in f_shift is: 10 ">" 8 ">" 4, i.e.
+	 * if bit 10 set then bit 8 and bit 4 don't care...
+	 * If all these bits are 0 get display depth from st_shift
+	 * (as for ST and STE)
+	 */
+	if (hw->f_shift & 0x400)		/* 2 colors */
+		var->bits_per_pixel = 1;
+	else if (hw->f_shift & 0x100)	/* hicolor */
+		var->bits_per_pixel = 16;
+	else if (hw->f_shift & 0x010)	/* 8 bitplanes */
+		var->bits_per_pixel = 8;
+	else if (hw->st_shift == 0)
+		var->bits_per_pixel = 4;
+	else if (hw->st_shift == 0x100)
+		var->bits_per_pixel = 2;
+	else /* if (hw->st_shift == 0x200) */
+		var->bits_per_pixel = 1;
+
+	var->xres = hw->line_width * 16 / var->bits_per_pixel;
+	var->xres_virtual = var->xres + hw->line_offset * 16 / var->bits_per_pixel;
+	if (hw->xoffset)
+		var->xres_virtual += 16;
+
+	if (var->bits_per_pixel == 16) {
+		var->red.offset=11;
+		var->red.length=5;
+		var->red.msb_right=0;
+		var->green.offset=5;
+		var->green.length=6;
+		var->green.msb_right=0;
+		var->blue.offset=0;
+		var->blue.length=5;
+		var->blue.msb_right=0;
+	}
+	else {
+		var->red.offset=0;
+		var->red.length = hw->ste_mode ? 4 : 6;
+		var->red.msb_right=0;
+		var->grayscale=0;
+		var->blue=var->green=var->red;
+	}
+	var->transp.offset=0;
+	var->transp.length=0;
+	var->transp.msb_right=0;
+
+	linelen = var->xres_virtual * var->bits_per_pixel / 8;
+	if (screen_len) {
+		if (par->yres_virtual)
+			var->yres_virtual = par->yres_virtual;
+		else
+			/* yres_virtual==0 means use maximum */
+			var->yres_virtual = screen_len / linelen;
+	}
+	else {
+		if (hwscroll < 0)
+			var->yres_virtual = 2 * var->yres;
+		else
+			var->yres_virtual=var->yres+hwscroll * 16;
+	}
+	var->xoffset=0; /* TODO change this */
+
+	/* hdX-offsets */
+	prescale = hxx_prescale(hw);
+	plen = 4 >> (hw->vid_mode >> 2 & 0x3);
+	base_off = hw->vid_control & VCO_SHORTOFFS ? 64 : 128;
+	if (hw->f_shift & 0x100) {
+		hde_off = 0;
+		hdb_off = (base_off + 16 * plen) + prescale;
+	}
+	else {
+		hde_off = ((128 / var->bits_per_pixel + 2) * plen);
+		if (hw->ste_mode)
+			hdb_off = (64 + base_off + (128 / var->bits_per_pixel + 2) * plen)
+					 + prescale;
+		else
+			hdb_off = (base_off + (128 / var->bits_per_pixel + 18) * plen)
+					 + prescale;
+	}
+
+	/* Right margin includes hsync */
+	var->left_margin = hdb_off + prescale * ((hw->hdb & 0x1ff) -
+					   (hw->hdb & 0x200 ? 2+hw->hht : 0));
+	if (hw->ste_mode || mon_type!=F_MON_VGA)
+		var->right_margin = prescale * (hw->hht + 2 - hw->hde) - hde_off;
+	else
+		/* can't use this in ste_mode, because hbb is +1 off */
+		var->right_margin = prescale * (hw->hht + 2 - hw->hbb);
+	var->hsync_len = prescale * (hw->hht + 2 - hw->hss);
+
+	/* Lower margin includes vsync */
+	var->upper_margin = hw->vdb / 2 ;  /* round down to full lines */
+	var->lower_margin = (hw->vft+1 - hw->vde + 1) / 2; /* round up */
+	var->vsync_len    = (hw->vft+1 - hw->vss + 1) / 2; /* round up */
+	if (var->vmode & FB_VMODE_INTERLACED) {
+		var->upper_margin *= 2;
+		var->lower_margin *= 2;
+		var->vsync_len *= 2;
+	}
+	else if (var->vmode & FB_VMODE_DOUBLE) {
+		var->upper_margin = (var->upper_margin + 1) / 2;
+		var->lower_margin = (var->lower_margin + 1) / 2;
+		var->vsync_len = (var->vsync_len + 1) / 2;
+	}
+
+	var->pixclock *= plen;
+	var->left_margin /= plen;
+	var->right_margin /= plen;
+	var->hsync_len /= plen;
+
+	var->right_margin -= var->hsync_len;
+	var->lower_margin -= var->vsync_len;
+
+	if (screen_base)
+		var->yoffset=(par->screen_base - screen_base)/linelen;
+	else
+		var->yoffset=0;
+	var->nonstd=0;	/* what is this for? */
+	var->activate=0;
+	return 0;
+}
+
+
+static int f_change_mode = 0;
+static struct falcon_hw f_new_mode;
+static int f_pan_display = 0;
+
+static void falcon_get_par( struct atafb_par *par )
+{
+	unsigned long addr;
+	struct falcon_hw *hw = &par->hw.falcon;
+
+	hw->line_width = shifter_f030.scn_width;
+	hw->line_offset = shifter_f030.off_next;
+	hw->st_shift = videl.st_shift & 0x300;
+	hw->f_shift = videl.f_shift;
+	hw->vid_control = videl.control;
+	hw->vid_mode = videl.mode;
+	hw->sync = shifter.syncmode & 0x1;
+	hw->xoffset = videl.xoffset & 0xf;
+	hw->hht = videl.hht;
+	hw->hbb = videl.hbb;
+	hw->hbe = videl.hbe;
+	hw->hdb = videl.hdb;
+	hw->hde = videl.hde;
+	hw->hss = videl.hss;
+	hw->vft = videl.vft;
+	hw->vbb = videl.vbb;
+	hw->vbe = videl.vbe;
+	hw->vdb = videl.vdb;
+	hw->vde = videl.vde;
+	hw->vss = videl.vss;
+
+	addr = (shifter.bas_hi & 0xff) << 16 |
+	       (shifter.bas_md & 0xff) << 8  |
+	       (shifter.bas_lo & 0xff);
+	par->screen_base = phys_to_virt(addr);
+
+	/* derived parameters */
+	hw->ste_mode = (hw->f_shift & 0x510)==0 && hw->st_shift==0x100;
+	hw->mono = (hw->f_shift & 0x400) ||
+	           ((hw->f_shift & 0x510)==0 && hw->st_shift==0x200);
+}
+
+static void falcon_set_par( struct atafb_par *par )
+{
+	f_change_mode = 0;
+
+	/* only set screen_base if really necessary */
+	if (current_par.screen_base != par->screen_base)
+		fbhw->set_screen_base(par->screen_base);
+
+	/* Don't touch any other registers if we keep the default resolution */
+	if (DontCalcRes)
+		return;
+
+	/* Tell vbl-handler to change video mode.
+	 * We change modes only on next VBL, to avoid desynchronisation
+	 * (a shift to the right and wrap around by a random number of pixels
+	 * in all monochrome modes).
+	 * This seems to work on my Falcon.
+	 */
+	f_new_mode = par->hw.falcon;
+	f_change_mode = 1;
+}
+
+
+static irqreturn_t falcon_vbl_switcher( int irq, void *dummy, struct pt_regs *fp )
+{
+	struct falcon_hw *hw = &f_new_mode;
+
+	if (f_change_mode) {
+		f_change_mode = 0;
+
+		if (hw->sync & 0x1) {
+			/* Enable external pixelclock. This code only for ScreenWonder */
+			*(volatile unsigned short*)0xffff9202 = 0xffbf;
+		}
+		else {
+			/* Turn off external clocks. Read sets all output bits to 1. */
+			*(volatile unsigned short*)0xffff9202;
+		}
+		shifter.syncmode = hw->sync;
+
+		videl.hht = hw->hht;
+		videl.hbb = hw->hbb;
+		videl.hbe = hw->hbe;
+		videl.hdb = hw->hdb;
+		videl.hde = hw->hde;
+		videl.hss = hw->hss;
+		videl.vft = hw->vft;
+		videl.vbb = hw->vbb;
+		videl.vbe = hw->vbe;
+		videl.vdb = hw->vdb;
+		videl.vde = hw->vde;
+		videl.vss = hw->vss;
+
+		videl.f_shift = 0; /* write enables Falcon palette, 0: 4 planes */
+		if (hw->ste_mode) {
+			videl.st_shift = hw->st_shift; /* write enables STE palette */
+		}
+		else {
+			/* IMPORTANT:
+			 * set st_shift 0, so we can tell the screen-depth if f_shift==0.
+			 * Writing 0 to f_shift enables 4 plane Falcon mode but
+			 * doesn't set st_shift. st_shift!=0 (!=4planes) is impossible
+			 * with Falcon palette.
+			 */
+			videl.st_shift = 0;
+			/* now back to Falcon palette mode */
+			videl.f_shift = hw->f_shift;
+		}
+		/* writing to st_shift changed scn_width and vid_mode */
+		videl.xoffset = hw->xoffset;
+		shifter_f030.scn_width = hw->line_width;
+		shifter_f030.off_next = hw->line_offset;
+		videl.control = hw->vid_control;
+		videl.mode = hw->vid_mode;
+	}
+	if (f_pan_display) {
+		f_pan_display = 0;
+		videl.xoffset = current_par.hw.falcon.xoffset;
+		shifter_f030.off_next = current_par.hw.falcon.line_offset;
+	}
+	return IRQ_HANDLED;
+}
+
+
+static int falcon_pan_display( struct fb_var_screeninfo *var,
+							   struct atafb_par *par )
+{
+	int xoffset;
+	int bpp = fb_display[fb_info.currcon].var.bits_per_pixel;
+
+	if (bpp == 1)
+		var->xoffset = up(var->xoffset, 32);
+	if (bpp != 16)
+		par->hw.falcon.xoffset = var->xoffset & 15;
+	else {
+		par->hw.falcon.xoffset = 0;
+		var->xoffset = up(var->xoffset, 2);
+	}
+	par->hw.falcon.line_offset = bpp *
+	       	(fb_display[fb_info.currcon].var.xres_virtual - fb_display[fb_info.currcon].var.xres) / 16;
+	if (par->hw.falcon.xoffset)
+		par->hw.falcon.line_offset -= bpp;
+	xoffset = var->xoffset - par->hw.falcon.xoffset;
+
+	par->screen_base = screen_base +
+	        (var->yoffset * fb_display[fb_info.currcon].var.xres_virtual + xoffset) * bpp / 8;
+	if (fbhw->set_screen_base)
+		fbhw->set_screen_base (par->screen_base);
+	else
+		return -EINVAL; /* shouldn't happen */
+	f_pan_display = 1;
+	return 0;
+}
+
+
+static int falcon_getcolreg( unsigned regno, unsigned *red,
+				 unsigned *green, unsigned *blue,
+				 unsigned *transp, struct fb_info *info )
+{	unsigned long col;
+	
+	if (regno > 255)
+		return 1;
+	/* This works in STE-mode (with 4bit/color) since f030_col-registers
+	 * hold up to 6bit/color.
+	 * Even with hicolor r/g/b=5/6/5 bit!
+	 */
+	col = f030_col[regno];
+	*red = (col >> 16) & 0xff00;
+	*green = (col >> 8) & 0xff00;
+	*blue = (col << 8) & 0xff00;
+	*transp = 0;
+	return 0;
+}
+
+
+static int falcon_setcolreg( unsigned regno, unsigned red,
+							 unsigned green, unsigned blue,
+							 unsigned transp, struct fb_info *info )
+{
+	if (regno > 255)
+		return 1;
+	f030_col[regno] = (((red & 0xfc00) << 16) |
+			   ((green & 0xfc00) << 8) |
+			   ((blue & 0xfc00) >> 8));
+	if (regno < 16) {
+		shifter_tt.color_reg[regno] =
+			(((red & 0xe000) >> 13) | ((red & 0x1000) >> 12) << 8) |
+			(((green & 0xe000) >> 13) | ((green & 0x1000) >> 12) << 4) |
+			((blue & 0xe000) >> 13) | ((blue & 0x1000) >> 12);
+#ifdef FBCON_HAS_CFB16
+		fbcon_cfb16_cmap[regno] = ((red & 0xf800) |
+					   ((green & 0xfc00) >> 5) |
+					   ((blue & 0xf800) >> 11));
+#endif
+	}
+	return 0;
+}
+
+
+static int falcon_blank( int blank_mode )
+{
+/* ++guenther: we can switch off graphics by changing VDB and VDE,
+ * so VIDEL doesn't hog the bus while saving.
+ * (this may affect usleep()).
+ */
+	int vdb, vss, hbe, hss;
+
+	if (mon_type == F_MON_SM)	/* this doesn't work on SM124 */
+		return 1;
+
+	vdb = current_par.VDB;
+	vss = current_par.VSS;
+	hbe = current_par.HBE;
+	hss = current_par.HSS;
+
+	if (blank_mode >= 1) {
+		/* disable graphics output (this speeds up the CPU) ... */
+		vdb = current_par.VFT + 1;
+		/* ... and blank all lines */
+		hbe = current_par.HHT + 2;
+	}
+	/* use VESA suspend modes on VGA monitors */
+	if (mon_type == F_MON_VGA) {
+		if (blank_mode == 2 || blank_mode == 4)
+			vss = current_par.VFT + 1;
+		if (blank_mode == 3 || blank_mode == 4)
+			hss = current_par.HHT + 2;
+	}
+
+	videl.vdb = vdb;
+	videl.vss = vss;
+	videl.hbe = hbe;
+	videl.hss = hss;
+
+	return 0;
+}
+
+ 
+static int falcon_detect( void )
+{
+	struct atafb_par par;
+	unsigned char fhw;
+
+	/* Determine connected monitor and set monitor parameters */
+	fhw = *(unsigned char*)0xffff8006;
+	mon_type = fhw >> 6 & 0x3;
+	/* bit 1 of fhw: 1=32 bit ram bus, 0=16 bit */
+	f030_bus_width = fhw << 6 & 0x80;
+	switch (mon_type) {
+	case F_MON_SM:
+		fb_info.monspecs.vfmin = 70;
+		fb_info.monspecs.vfmax = 72;
+		fb_info.monspecs.hfmin = 35713;
+		fb_info.monspecs.hfmax = 35715;
+		break;
+	case F_MON_SC:
+	case F_MON_TV:
+		/* PAL...NTSC */
+		fb_info.monspecs.vfmin = 49; /* not 50, since TOS defaults to 49.9x Hz */
+		fb_info.monspecs.vfmax = 60;
+		fb_info.monspecs.hfmin = 15620;
+		fb_info.monspecs.hfmax = 15755;
+		break;
+	}
+	/* initialize hsync-len */
+	f25.hsync = h_syncs[mon_type] / f25.t;
+	f32.hsync = h_syncs[mon_type] / f32.t;
+	if (fext.t)
+		fext.hsync = h_syncs[mon_type] / fext.t;
+
+	falcon_get_par(&par);
+	falcon_encode_var(&atafb_predefined[0], &par);
+
+	/* Detected mode is always the "autodetect" slot */
+	return 1;
+}
+
+#endif /* ATAFB_FALCON */
+
+/* ------------------- ST(E) specific functions ---------------------- */
+
+#ifdef ATAFB_STE
+
+static int stste_encode_fix( struct fb_fix_screeninfo *fix,
+							 struct atafb_par *par )
+
+{
+	int mode;
+
+	strcpy(fix->id,"Atari Builtin");
+	fix->smem_start = (unsigned long)real_screen_base;
+	fix->smem_len = screen_len;
+	fix->type = FB_TYPE_INTERLEAVED_PLANES;
+	fix->type_aux = 2;
+	fix->visual = FB_VISUAL_PSEUDOCOLOR;
+	mode = par->hw.st.mode & 3;
+	if (mode == ST_HIGH) {
+		fix->type = FB_TYPE_PACKED_PIXELS;
+		fix->type_aux = 0;
+		fix->visual = FB_VISUAL_MONO10;
+	}
+	if (ATARIHW_PRESENT(EXTD_SHIFTER)) {
+		fix->xpanstep = 16;
+		fix->ypanstep = 1;
+	} else {
+		fix->xpanstep = 0;
+		fix->ypanstep = 0;
+	}
+	fix->ywrapstep = 0;
+	fix->line_length = 0;
+	fix->accel = FB_ACCEL_ATARIBLITT;
+	return 0;
+}
+
+
+static int stste_decode_var( struct fb_var_screeninfo *var,
+						  struct atafb_par *par )
+{
+	int xres=var->xres;
+	int yres=var->yres;
+	int bpp=var->bits_per_pixel;
+	int linelen;
+	int yres_virtual = var->yres_virtual;
+
+	if (mono_moni) {
+		if (bpp > 1 || xres > sttt_xres || yres > st_yres)
+			return -EINVAL;
+		par->hw.st.mode=ST_HIGH;
+		xres=sttt_xres;
+		yres=st_yres;
+		bpp=1;
+	} else {
+		if (bpp > 4 || xres > sttt_xres || yres > st_yres)
+			return -EINVAL;
+		if (bpp > 2) {
+			if (xres > sttt_xres/2 || yres > st_yres/2)
+				return -EINVAL;
+			par->hw.st.mode=ST_LOW;
+			xres=sttt_xres/2;
+			yres=st_yres/2;
+			bpp=4;
+		}
+		else if (bpp > 1) {
+			if (xres > sttt_xres || yres > st_yres/2)
+				return -EINVAL;
+			par->hw.st.mode=ST_MID;
+			xres=sttt_xres;
+			yres=st_yres/2;
+			bpp=2;
+		}
+		else
+			return -EINVAL;
+	}
+	if (yres_virtual <= 0)
+		yres_virtual = 0;
+	else if (yres_virtual < yres)
+		yres_virtual = yres;
+	if (var->sync & FB_SYNC_EXT)
+		par->hw.st.sync=(par->hw.st.sync & ~1) | 1;
+	else
+		par->hw.st.sync=(par->hw.st.sync & ~1);
+	linelen=xres*bpp/8;
+	if (yres_virtual * linelen > screen_len && screen_len)
+		return -EINVAL;
+	if (yres * linelen > screen_len && screen_len)
+		return -EINVAL;
+	if (var->yoffset + yres > yres_virtual && yres_virtual)
+		return -EINVAL;
+	par->yres_virtual = yres_virtual;
+	par->screen_base=screen_base+ var->yoffset*linelen;
+	return 0;
+}
+
+static int stste_encode_var( struct fb_var_screeninfo *var,
+						  struct atafb_par *par )
+{
+	int linelen;
+	memset(var, 0, sizeof(struct fb_var_screeninfo));
+	var->red.offset=0;
+	var->red.length = ATARIHW_PRESENT(EXTD_SHIFTER) ? 4 : 3;
+	var->red.msb_right=0;
+	var->grayscale=0;
+
+	var->pixclock=31041;
+	var->left_margin=120;		/* these are incorrect */
+	var->right_margin=100;
+	var->upper_margin=8;
+	var->lower_margin=16;
+	var->hsync_len=140;
+	var->vsync_len=30;
+
+	var->height=-1;
+	var->width=-1;
+
+	if (!(par->hw.st.sync & 1))
+		var->sync=0;
+	else
+		var->sync=FB_SYNC_EXT;
+
+	switch (par->hw.st.mode & 3) {
+	case ST_LOW:
+		var->xres=sttt_xres/2;
+		var->yres=st_yres/2;
+		var->bits_per_pixel=4;
+		break;
+	case ST_MID:
+		var->xres=sttt_xres;
+		var->yres=st_yres/2;
+		var->bits_per_pixel=2;
+		break;
+	case ST_HIGH:
+		var->xres=sttt_xres;
+		var->yres=st_yres;
+		var->bits_per_pixel=1;
+		break;
+	}		
+	var->blue=var->green=var->red;
+	var->transp.offset=0;
+	var->transp.length=0;
+	var->transp.msb_right=0;
+	var->xres_virtual=sttt_xres_virtual;
+	linelen=var->xres_virtual * var->bits_per_pixel / 8;
+	ovsc_addlen=linelen*(sttt_yres_virtual - st_yres);
+	
+	if (! use_hwscroll)
+		var->yres_virtual=var->yres;
+	else if (screen_len) {
+		if (par->yres_virtual)
+			var->yres_virtual = par->yres_virtual;
+		else
+			/* yres_virtual==0 means use maximum */
+			var->yres_virtual = screen_len / linelen;
+	}
+	else {
+		if (hwscroll < 0)
+			var->yres_virtual = 2 * var->yres;
+		else
+			var->yres_virtual=var->yres+hwscroll * 16;
+	}
+	var->xoffset=0;
+	if (screen_base)
+		var->yoffset=(par->screen_base - screen_base)/linelen;
+	else
+		var->yoffset=0;
+	var->nonstd=0;
+	var->activate=0;
+	var->vmode=FB_VMODE_NONINTERLACED;
+	return 0;
+}
+
+
+static void stste_get_par( struct atafb_par *par )
+{
+	unsigned long addr;
+	par->hw.st.mode=shifter_tt.st_shiftmode;
+	par->hw.st.sync=shifter.syncmode;
+	addr = ((shifter.bas_hi & 0xff) << 16) |
+	       ((shifter.bas_md & 0xff) << 8);
+	if (ATARIHW_PRESENT(EXTD_SHIFTER))
+		addr |= (shifter.bas_lo & 0xff);
+	par->screen_base = phys_to_virt(addr);
+}
+
+static void stste_set_par( struct atafb_par *par )
+{
+	shifter_tt.st_shiftmode=par->hw.st.mode;
+	shifter.syncmode=par->hw.st.sync;
+	/* only set screen_base if really necessary */
+	if (current_par.screen_base != par->screen_base)
+		fbhw->set_screen_base(par->screen_base);
+}
+
+
+static int stste_getcolreg(unsigned regno, unsigned *red,
+			   unsigned *green, unsigned *blue,
+			   unsigned *transp, struct fb_info *info)
+{
+	unsigned col, t;
+	
+	if (regno > 15)
+		return 1;
+	col = shifter_tt.color_reg[regno];
+	if (ATARIHW_PRESENT(EXTD_SHIFTER)) {
+		t = ((col >> 7) & 0xe) | ((col >> 11) & 1);
+		t |= t << 4;
+		*red = t | (t << 8);
+		t = ((col >> 3) & 0xe) | ((col >> 7) & 1);
+		t |= t << 4;
+		*green = t | (t << 8);
+		t = ((col << 1) & 0xe) | ((col >> 3) & 1);
+		t |= t << 4;
+		*blue = t | (t << 8);
+	}
+	else {
+		t = (col >> 7) & 0xe;
+		t |= t << 4;
+		*red = t | (t << 8);
+		t = (col >> 3) & 0xe;
+		t |= t << 4;
+		*green = t | (t << 8);
+		t = (col << 1) & 0xe;
+		t |= t << 4;
+		*blue = t | (t << 8);
+	}
+	*transp = 0;
+	return 0;
+}
+
+
+static int stste_setcolreg(unsigned regno, unsigned red,
+			   unsigned green, unsigned blue,
+			   unsigned transp, struct fb_info *info)
+{
+	if (regno > 15)
+		return 1;
+	red >>= 12;
+	blue >>= 12;
+	green >>= 12;
+	if (ATARIHW_PRESENT(EXTD_SHIFTER))
+		shifter_tt.color_reg[regno] =
+			(((red & 0xe) >> 1) | ((red & 1) << 3) << 8) |
+			(((green & 0xe) >> 1) | ((green & 1) << 3) << 4) |
+			((blue & 0xe) >> 1) | ((blue & 1) << 3);
+	else
+		shifter_tt.color_reg[regno] =
+			((red & 0xe) << 7) |
+			((green & 0xe) << 3) |
+			((blue & 0xe) >> 1);
+	return 0;
+}
+
+						  
+static int stste_detect( void )
+
+{	struct atafb_par par;
+
+	/* Determine the connected monitor: The DMA sound must be
+	 * disabled before reading the MFP GPIP, because the Sound
+	 * Done Signal and the Monochrome Detect are XORed together!
+	 */
+	if (ATARIHW_PRESENT(PCM_8BIT)) {
+		tt_dmasnd.ctrl = DMASND_CTRL_OFF;
+		udelay(20);	/* wait a while for things to settle down */
+	}
+	mono_moni = (mfp.par_dt_reg & 0x80) == 0;
+
+	stste_get_par(&par);
+	stste_encode_var(&atafb_predefined[0], &par);
+
+	if (!ATARIHW_PRESENT(EXTD_SHIFTER))
+		use_hwscroll = 0;
+	return 1;
+}
+
+static void stste_set_screen_base(void *s_base)
+{
+	unsigned long addr;
+	addr= virt_to_phys(s_base);
+	/* Setup Screen Memory */
+	shifter.bas_hi=(unsigned char) ((addr & 0xff0000) >> 16);
+  	shifter.bas_md=(unsigned char) ((addr & 0x00ff00) >> 8);
+	if (ATARIHW_PRESENT(EXTD_SHIFTER))
+		shifter.bas_lo=(unsigned char)  (addr & 0x0000ff);
+}
+
+#endif /* ATAFB_STE */
+
+/* Switching the screen size should be done during vsync, otherwise
+ * the margins may get messed up. This is a well known problem of
+ * the ST's video system.
+ *
+ * Unfortunately there is hardly any way to find the vsync, as the
+ * vertical blank interrupt is no longer in time on machines with
+ * overscan type modifications.
+ *
+ * We can, however, use Timer B to safely detect the black shoulder,
+ * but then we've got to guess an appropriate delay to find the vsync.
+ * This might not work on every machine.
+ *
+ * martin_rogge @ ki.maus.de, 8th Aug 1995
+ */
+
+#define LINE_DELAY  (mono_moni ? 30 : 70)
+#define SYNC_DELAY  (mono_moni ? 1500 : 2000)
+
+/* SWITCH_ACIA may be used for Falcon (ScreenBlaster III internal!) */
+static void st_ovsc_switch(void)
+{
+    unsigned long flags;
+    register unsigned char old, new;
+
+    if (!(atari_switches & ATARI_SWITCH_OVSC_MASK))
+	return;
+    local_irq_save(flags);
+
+    mfp.tim_ct_b = 0x10;
+    mfp.active_edge |= 8;
+    mfp.tim_ct_b = 0;
+    mfp.tim_dt_b = 0xf0;
+    mfp.tim_ct_b = 8;
+    while (mfp.tim_dt_b > 1)	/* TOS does it this way, don't ask why */
+	;
+    new = mfp.tim_dt_b;
+    do {
+	udelay(LINE_DELAY);
+	old = new;
+	new = mfp.tim_dt_b;
+    } while (old != new);
+    mfp.tim_ct_b = 0x10;
+    udelay(SYNC_DELAY);
+
+    if (atari_switches & ATARI_SWITCH_OVSC_IKBD)
+	acia.key_ctrl = ACIA_DIV64 | ACIA_D8N1S | ACIA_RHTID | ACIA_RIE;
+    if (atari_switches & ATARI_SWITCH_OVSC_MIDI)
+	acia.mid_ctrl = ACIA_DIV16 | ACIA_D8N1S | ACIA_RHTID;
+    if (atari_switches & (ATARI_SWITCH_OVSC_SND6|ATARI_SWITCH_OVSC_SND7)) {
+	sound_ym.rd_data_reg_sel = 14;
+	sound_ym.wd_data = sound_ym.rd_data_reg_sel |
+			   ((atari_switches&ATARI_SWITCH_OVSC_SND6) ? 0x40:0) |
+			   ((atari_switches&ATARI_SWITCH_OVSC_SND7) ? 0x80:0);
+    }
+    local_irq_restore(flags);
+}
+
+/* ------------------- External Video ---------------------- */
+
+#ifdef ATAFB_EXT
+
+static int ext_encode_fix( struct fb_fix_screeninfo *fix,
+						   struct atafb_par *par )
+
+{
+	strcpy(fix->id,"Unknown Extern");
+	fix->smem_start = (unsigned long)external_addr;
+	fix->smem_len = PAGE_ALIGN(external_len);
+	if (external_depth == 1) {
+		fix->type = FB_TYPE_PACKED_PIXELS;
+		/* The letters 'n' and 'i' in the "atavideo=external:" stand
+		 * for "normal" and "inverted", rsp., in the monochrome case */
+		fix->visual =
+			(external_pmode == FB_TYPE_INTERLEAVED_PLANES ||
+			 external_pmode == FB_TYPE_PACKED_PIXELS) ?
+				FB_VISUAL_MONO10 :
+					FB_VISUAL_MONO01;
+	}
+	else {
+		/* Use STATIC if we don't know how to access color registers */
+		int visual = external_vgaiobase ?
+					 FB_VISUAL_PSEUDOCOLOR :
+					 FB_VISUAL_STATIC_PSEUDOCOLOR;
+		switch (external_pmode) {
+		    case -1:              /* truecolor */
+			fix->type=FB_TYPE_PACKED_PIXELS;
+			fix->visual=FB_VISUAL_TRUECOLOR;
+			break;
+		    case FB_TYPE_PACKED_PIXELS:
+			fix->type=FB_TYPE_PACKED_PIXELS;
+			fix->visual=visual;
+			break;
+		    case FB_TYPE_PLANES:
+			fix->type=FB_TYPE_PLANES;
+			fix->visual=visual;
+			break;
+		    case FB_TYPE_INTERLEAVED_PLANES:
+			fix->type=FB_TYPE_INTERLEAVED_PLANES;
+			fix->type_aux=2;
+			fix->visual=visual;
+			break;
+		}
+	}
+	fix->xpanstep = 0;
+	fix->ypanstep = 0;
+	fix->ywrapstep = 0;
+	fix->line_length = 0;
+	return 0;
+}
+
+
+static int ext_decode_var( struct fb_var_screeninfo *var,
+						   struct atafb_par *par )
+{
+	struct fb_var_screeninfo *myvar = &atafb_predefined[0];
+	
+	if (var->bits_per_pixel > myvar->bits_per_pixel ||
+		var->xres > myvar->xres ||
+		var->xres_virtual > myvar->xres_virtual ||
+		var->yres > myvar->yres ||
+		var->xoffset > 0 ||
+		var->yoffset > 0)
+		return -EINVAL;
+	return 0;
+}
+
+
+static int ext_encode_var( struct fb_var_screeninfo *var,
+						   struct atafb_par *par )
+{
+	memset(var, 0, sizeof(struct fb_var_screeninfo));
+	var->red.offset=0;
+	var->red.length=(external_pmode == -1) ? external_depth/3 : 
+			(external_vgaiobase ? external_bitspercol : 0);
+	var->red.msb_right=0;
+	var->grayscale=0;
+
+	var->pixclock=31041;
+	var->left_margin=120;		/* these are surely incorrect 	*/
+	var->right_margin=100;
+	var->upper_margin=8;
+	var->lower_margin=16;
+	var->hsync_len=140;
+	var->vsync_len=30;
+
+	var->height=-1;
+	var->width=-1;
+
+	var->sync=0;
+
+	var->xres = external_xres;
+	var->yres = external_yres;
+	var->xres_virtual = external_xres_virtual;
+	var->bits_per_pixel = external_depth;
+	
+	var->blue=var->green=var->red;
+	var->transp.offset=0;
+	var->transp.length=0;
+	var->transp.msb_right=0;
+	var->yres_virtual=var->yres;
+	var->xoffset=0;
+	var->yoffset=0;
+	var->nonstd=0;
+	var->activate=0;
+	var->vmode=FB_VMODE_NONINTERLACED;
+	return 0;
+}
+
+
+static void ext_get_par( struct atafb_par *par )
+{
+	par->screen_base = external_addr;
+}
+
+static void ext_set_par( struct atafb_par *par )
+{
+}
+
+#define OUTB(port,val) \
+	*((unsigned volatile char *) ((port)+external_vgaiobase))=(val)
+#define INB(port) \
+	(*((unsigned volatile char *) ((port)+external_vgaiobase)))
+#define DACDelay 				\
+	do {					\
+		unsigned char tmp=INB(0x3da);	\
+		tmp=INB(0x3da);			\
+	} while (0)
+
+static int ext_getcolreg( unsigned regno, unsigned *red,
+						  unsigned *green, unsigned *blue,
+						  unsigned *transp, struct fb_info *info )
+{
+	if (! external_vgaiobase)
+		return 1;
+
+	    *red   = ext_color[regno].red;
+	    *green = ext_color[regno].green;
+	    *blue  = ext_color[regno].blue;
+	    *transp=0;
+	    return 0;
+}
+	
+static int ext_setcolreg( unsigned regno, unsigned red,
+						  unsigned green, unsigned blue,
+						  unsigned transp, struct fb_info *info )
+
+{	unsigned char colmask = (1 << external_bitspercol) - 1;
+
+	if (! external_vgaiobase)
+		return 1;
+
+	ext_color[regno].red = red;
+	ext_color[regno].green = green;
+	ext_color[regno].blue = blue;
+
+	switch (external_card_type) {
+	  case IS_VGA:
+	    OUTB(0x3c8, regno);
+	    DACDelay;
+	    OUTB(0x3c9, red & colmask);
+	    DACDelay;
+	    OUTB(0x3c9, green & colmask);
+	    DACDelay;
+	    OUTB(0x3c9, blue & colmask);
+	    DACDelay;
+	    return 0;
+
+	  case IS_MV300:
+	    OUTB((MV300_reg[regno] << 2)+1, red);
+	    OUTB((MV300_reg[regno] << 2)+1, green);
+	    OUTB((MV300_reg[regno] << 2)+1, blue);
+	    return 0;
+
+	  default:
+	    return 1;
+	  }
+}
+	
+
+static int ext_detect( void )
+
+{
+	struct fb_var_screeninfo *myvar = &atafb_predefined[0];
+	struct atafb_par dummy_par;
+
+	myvar->xres = external_xres;
+	myvar->xres_virtual = external_xres_virtual;
+	myvar->yres = external_yres;
+	myvar->bits_per_pixel = external_depth;
+	ext_encode_var(myvar, &dummy_par);
+	return 1;
+}
+
+#endif /* ATAFB_EXT */
+
+/* ------ This is the same for most hardware types -------- */
+
+static void set_screen_base(void *s_base)
+{
+	unsigned long addr;
+	addr= virt_to_phys(s_base);
+	/* Setup Screen Memory */
+	shifter.bas_hi=(unsigned char) ((addr & 0xff0000) >> 16);
+  	shifter.bas_md=(unsigned char) ((addr & 0x00ff00) >> 8);
+  	shifter.bas_lo=(unsigned char)  (addr & 0x0000ff);
+}
+
+
+static int pan_display( struct fb_var_screeninfo *var,
+                        struct atafb_par *par )
+{
+	if (!fbhw->set_screen_base ||
+		(!ATARIHW_PRESENT(EXTD_SHIFTER) && var->xoffset))
+		return -EINVAL;
+	var->xoffset = up(var->xoffset, 16);
+	par->screen_base = screen_base +
+	        (var->yoffset * fb_display[fb_info.currcon].var.xres_virtual + var->xoffset)
+	        * fb_display[fb_info.currcon].var.bits_per_pixel / 8;
+	fbhw->set_screen_base (par->screen_base);
+	return 0;
+}
+
+
+/* ------------ Interfaces to hardware functions ------------ */
+
+
+#ifdef ATAFB_TT
+static struct fb_hwswitch tt_switch = {
+	tt_detect, tt_encode_fix, tt_decode_var, tt_encode_var,
+	tt_get_par, tt_set_par, tt_getcolreg, 
+	set_screen_base, NULL, pan_display
+};
+#endif
+
+#ifdef ATAFB_FALCON
+static struct fb_hwswitch falcon_switch = {
+	falcon_detect, falcon_encode_fix, falcon_decode_var, falcon_encode_var,
+	falcon_get_par, falcon_set_par, falcon_getcolreg,
+	set_screen_base, falcon_blank, falcon_pan_display
+};
+#endif
+
+#ifdef ATAFB_STE
+static struct fb_hwswitch st_switch = {
+	stste_detect, stste_encode_fix, stste_decode_var, stste_encode_var,
+	stste_get_par, stste_set_par, stste_getcolreg,
+	stste_set_screen_base, NULL, pan_display
+};
+#endif
+
+#ifdef ATAFB_EXT
+static struct fb_hwswitch ext_switch = {
+	ext_detect, ext_encode_fix, ext_decode_var, ext_encode_var,
+	ext_get_par, ext_set_par, ext_getcolreg, NULL, NULL, NULL
+};
+#endif
+
+
+
+static void atafb_get_par( struct atafb_par *par )
+{
+	if (current_par_valid) {
+		*par=current_par;
+	}
+	else
+		fbhw->get_par(par);
+}
+
+
+static void atafb_set_par( struct atafb_par *par )
+{
+	fbhw->set_par(par);
+	current_par=*par;
+	current_par_valid=1;
+}
+
+
+
+/* =========================================================== */
+/* ============== Hardware Independent Functions ============= */
+/* =========================================================== */
+
+
+/* used for hardware scrolling */
+
+static int
+fb_update_var(int con, struct fb_info *info)
+{
+	int off=fb_display[con].var.yoffset*fb_display[con].var.xres_virtual*
+			fb_display[con].var.bits_per_pixel>>3;
+
+	current_par.screen_base=screen_base + off;
+
+	if (fbhw->set_screen_base)
+		fbhw->set_screen_base(current_par.screen_base);
+	return 0;
+}
+
+static int
+do_fb_set_var(struct fb_var_screeninfo *var, int isactive)
+{
+	int err,activate;
+	struct atafb_par par;
+	if ((err=fbhw->decode_var(var, &par)))
+		return err;
+	activate=var->activate;
+	if (((var->activate & FB_ACTIVATE_MASK) == FB_ACTIVATE_NOW) && isactive)
+		atafb_set_par(&par);
+	fbhw->encode_var(var, &par);
+	var->activate=activate;
+	return 0;
+}
+
+static int
+atafb_get_fix(struct fb_fix_screeninfo *fix, int con, struct fb_info *info)
+{
+	struct atafb_par par;
+	if (con == -1)
+		atafb_get_par(&par);
+	else {
+	  int err;
+		if ((err=fbhw->decode_var(&fb_display[con].var,&par)))
+		  return err;
+	}
+	memset(fix, 0, sizeof(struct fb_fix_screeninfo));
+	return fbhw->encode_fix(fix, &par);
+}
+	
+static int
+atafb_get_var(struct fb_var_screeninfo *var, int con, struct fb_info *info)
+{
+	struct atafb_par par;
+	if (con == -1) {
+		atafb_get_par(&par);
+		fbhw->encode_var(var, &par);
+	}
+	else
+		*var=fb_display[con].var;
+	return 0;
+}
+
+static void
+atafb_set_disp(int con, struct fb_info *info)
+{
+	struct fb_fix_screeninfo fix;
+	struct fb_var_screeninfo var;
+	struct display *display;
+
+	if (con >= 0)
+		display = &fb_display[con];
+	else
+		display = &disp;	/* used during initialization */
+
+	atafb_get_fix(&fix, con, info);
+	atafb_get_var(&var, con, info);
+	if (con == -1)
+		con=0;
+	info->screen_base = (void *)fix.smem_start;
+	display->visual = fix.visual;
+	display->type = fix.type;
+	display->type_aux = fix.type_aux;
+	display->ypanstep = fix.ypanstep;
+	display->ywrapstep = fix.ywrapstep;
+	display->line_length = fix.line_length;
+	if (fix.visual != FB_VISUAL_PSEUDOCOLOR &&
+		fix.visual != FB_VISUAL_DIRECTCOLOR)
+		display->can_soft_blank = 0;
+	else
+		display->can_soft_blank = 1;
+	display->inverse =
+	    (fix.visual == FB_VISUAL_MONO01 ? !inverse : inverse);
+	switch (fix.type) {
+	    case FB_TYPE_INTERLEAVED_PLANES:
+		switch (var.bits_per_pixel) {
+#ifdef FBCON_HAS_IPLAN2P2
+		    case 2:
+			display->dispsw = &fbcon_iplan2p2;
+			break;
+#endif
+#ifdef FBCON_HAS_IPLAN2P4
+		    case 4:
+			display->dispsw = &fbcon_iplan2p4;
+			break;
+#endif
+#ifdef FBCON_HAS_IPLAN2P8
+		    case 8:
+			display->dispsw = &fbcon_iplan2p8;
+			break;
+#endif
+		}
+		break;
+	    case FB_TYPE_PACKED_PIXELS:
+		switch (var.bits_per_pixel) {
+#ifdef FBCON_HAS_MFB
+		    case 1:
+			display->dispsw = &fbcon_mfb;
+			break;
+#endif
+#ifdef FBCON_HAS_CFB8
+		    case 8:
+			display->dispsw = &fbcon_cfb8;
+			break;
+#endif
+#ifdef FBCON_HAS_CFB16
+		    case 16:
+			display->dispsw = &fbcon_cfb16;
+			display->dispsw_data = fbcon_cfb16_cmap;
+			break;
+#endif
+		}
+		break;
+	}
+}
+
+static int
+atafb_set_var(struct fb_var_screeninfo *var, int con, struct fb_info *info)
+{
+	int err,oldxres,oldyres,oldbpp,oldxres_virtual,
+	    oldyres_virtual,oldyoffset;
+	if ((err=do_fb_set_var(var, con==info->currcon)))
+		return err;
+	if ((var->activate & FB_ACTIVATE_MASK) == FB_ACTIVATE_NOW) {
+		oldxres=fb_display[con].var.xres;
+		oldyres=fb_display[con].var.yres;
+		oldxres_virtual=fb_display[con].var.xres_virtual;
+		oldyres_virtual=fb_display[con].var.yres_virtual;
+		oldbpp=fb_display[con].var.bits_per_pixel;
+		oldyoffset=fb_display[con].var.yoffset;
+		fb_display[con].var=*var;
+		if (oldxres != var->xres || oldyres != var->yres 
+		    || oldxres_virtual != var->xres_virtual
+		    || oldyres_virtual != var->yres_virtual
+		    || oldbpp != var->bits_per_pixel
+		    || oldyoffset != var->yoffset) {
+			atafb_set_disp(con, info);
+			(*fb_info.changevar)(con);
+			fb_alloc_cmap(&fb_display[con].cmap, 0, 0);
+			do_install_cmap(con, info);
+		}
+	}
+	var->activate=0;
+	return 0;
+}
+
+
+
+static int
+atafb_get_cmap(struct fb_cmap *cmap, int kspc, int con, struct fb_info *info)
+{
+	if (con == info->currcon) /* current console ? */
+		return fb_get_cmap(cmap, kspc, fbhw->getcolreg, info);
+	else
+		if (fb_display[con].cmap.len) /* non default colormap ? */
+			fb_copy_cmap(&fb_display[con].cmap, cmap, kspc ? 0 : 2);
+		else
+			fb_copy_cmap(fb_default_cmap(1<<fb_display[con].var.bits_per_pixel),
+				     cmap, kspc ? 0 : 2);
+	return 0;
+}
+
+static int
+atafb_pan_display(struct fb_var_screeninfo *var, int con, struct fb_info *info)
+{
+	int xoffset = var->xoffset;
+	int yoffset = var->yoffset;
+	int err;
+
+	if (   xoffset < 0 || xoffset + fb_display[con].var.xres > fb_display[con].var.xres_virtual
+	    || yoffset < 0 || yoffset + fb_display[con].var.yres > fb_display[con].var.yres_virtual)
+		return -EINVAL;
+
+	if (con == info->currcon) {
+		if (fbhw->pan_display) {
+			if ((err = fbhw->pan_display(var, &current_par)))
+				return err;
+		}
+		else
+			return -EINVAL;
+	}
+	fb_display[con].var.xoffset = var->xoffset;
+	fb_display[con].var.yoffset = var->yoffset;
+	return 0;
+}
+
+static int
+atafb_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
+	       unsigned long arg, int con, struct fb_info *info)
+{
+	switch (cmd) {
+#ifdef FBCMD_GET_CURRENTPAR
+	case FBCMD_GET_CURRENTPAR:
+		if (copy_to_user((void *)arg, (void *)&current_par,
+				 sizeof(struct atafb_par)))
+			return -EFAULT;
+		return 0;
+#endif
+#ifdef FBCMD_SET_CURRENTPAR
+	case FBCMD_SET_CURRENTPAR:
+		if (copy_from_user((void *)&current_par, (void *)arg,
+				   sizeof(struct atafb_par)))
+			return -EFAULT;
+		atafb_set_par(&current_par);
+		return 0;
+#endif
+	}
+	return -EINVAL;
+}
+
+/* (un)blank/poweroff
+ * 0 = unblank
+ * 1 = blank
+ * 2 = suspend vsync
+ * 3 = suspend hsync
+ * 4 = off
+ */
+static int 
+atafb_blank(int blank, struct fb_info *info)
+{
+	unsigned short black[16];
+	struct fb_cmap cmap;
+	if (fbhw->blank && !fbhw->blank(blank))
+		return 1;
+	if (blank) {
+		memset(black, 0, 16*sizeof(unsigned short));
+		cmap.red=black;
+		cmap.green=black;
+		cmap.blue=black;
+		cmap.transp=NULL;
+		cmap.start=0;
+		cmap.len=16;
+		fb_set_cmap(&cmap, 1, info);
+	}
+	else
+		do_install_cmap(info->currcon, info);
+	return 0;
+}
+
+static struct fb_ops atafb_ops = {
+	.owner =	THIS_MODULE,
+	.fb_get_fix =	atafb_get_fix,
+	.fb_get_var =	atafb_get_var,
+	.fb_set_var =	atafb_set_var,
+	.fb_get_cmap =	atafb_get_cmap,
+	.fb_set_cmap =	gen_set_cmap,
+	.fb_pan_display =atafb_pan_display,
+	.fb_blank =	atafb_blank,
+	.fb_ioctl =	atafb_ioctl,
+};
+
+static void
+check_default_par( int detected_mode )
+{
+	char default_name[10];
+	int i;
+	struct fb_var_screeninfo var;
+	unsigned long min_mem;
+
+	/* First try the user supplied mode */
+	if (default_par) {
+		var=atafb_predefined[default_par-1];
+		var.activate = FB_ACTIVATE_TEST;
+		if (do_fb_set_var(&var,1))
+			default_par=0;		/* failed */
+	}
+	/* Next is the autodetected one */
+	if (! default_par) {
+		var=atafb_predefined[detected_mode-1]; /* autodetect */
+		var.activate = FB_ACTIVATE_TEST;
+		if (!do_fb_set_var(&var,1))
+			default_par=detected_mode;
+	}
+	/* If that also failed, try some default modes... */
+	if (! default_par) {
+		/* try default1, default2... */
+		for (i=1 ; i < 10 ; i++) {
+			sprintf(default_name,"default%d",i);
+			default_par=get_video_mode(default_name);
+			if (! default_par)
+				panic("can't set default video mode");
+			var=atafb_predefined[default_par-1];
+			var.activate = FB_ACTIVATE_TEST;
+			if (! do_fb_set_var(&var,1))
+				break;	/* ok */
+		}
+	}
+	min_mem=var.xres_virtual * var.yres_virtual * var.bits_per_pixel/8;
+	if (default_mem_req < min_mem)
+		default_mem_req=min_mem;
+}
+
+static int
+atafb_switch(int con, struct fb_info *info)
+{
+	/* Do we have to save the colormap ? */
+	if (fb_display[info->currcon].cmap.len)
+		fb_get_cmap(&fb_display[info->currcon].cmap, 1, fbhw->getcolreg,
+			    info);
+	do_fb_set_var(&fb_display[con].var,1);
+	info->currcon=con;
+	/* Install new colormap */
+	do_install_cmap(con, info);
+	return 0;
+}
+
+int __init atafb_init(void)
+{
+	int pad;
+	int detected_mode;
+	unsigned long mem_req;
+
+	if (!MACH_IS_ATARI)
+	        return -ENXIO;
+
+	do {
+#ifdef ATAFB_EXT
+		if (external_addr) {
+			fbhw = &ext_switch;
+			atafb_ops.fb_setcolreg = &ext_setcolreg;
+			break;
+		}
+#endif
+#ifdef ATAFB_TT
+		if (ATARIHW_PRESENT(TT_SHIFTER)) {
+			fbhw = &tt_switch;
+			atafb_ops.fb_setcolreg = &tt_setcolreg;
+			break;
+		}
+#endif
+#ifdef ATAFB_FALCON
+		if (ATARIHW_PRESENT(VIDEL_SHIFTER)) {
+			fbhw = &falcon_switch;
+			atafb_ops.fb_setcolreg = &falcon_setcolreg;
+			request_irq(IRQ_AUTO_4, falcon_vbl_switcher, IRQ_TYPE_PRIO,
+			            "framebuffer/modeswitch", falcon_vbl_switcher);
+			break;
+		}
+#endif
+#ifdef ATAFB_STE
+		if (ATARIHW_PRESENT(STND_SHIFTER) ||
+		    ATARIHW_PRESENT(EXTD_SHIFTER)) {
+			fbhw = &st_switch;
+			atafb_ops.fb_setcolreg = &stste_setcolreg;
+			break;
+		}
+		fbhw = &st_switch;
+		atafb_ops.fb_setcolreg = &stste_setcolreg;
+		printk("Cannot determine video hardware; defaulting to ST(e)\n");
+#else /* ATAFB_STE */
+		/* no default driver included */
+		/* Nobody will ever see this message :-) */
+		panic("Cannot initialize video hardware");
+#endif
+	} while (0);
+
+	/* Multisync monitor capabilities */
+	/* Atari-TOS defaults if no boot option present */
+	if (fb_info.monspecs.hfmin == 0) {
+	    fb_info.monspecs.hfmin = 31000;
+	    fb_info.monspecs.hfmax = 32000;
+	    fb_info.monspecs.vfmin = 58;
+	    fb_info.monspecs.vfmax = 62;
+	}
+
+	detected_mode = fbhw->detect();
+	check_default_par(detected_mode);
+#ifdef ATAFB_EXT
+	if (!external_addr) {
+#endif /* ATAFB_EXT */
+		mem_req = default_mem_req + ovsc_offset + ovsc_addlen;
+		mem_req = PAGE_ALIGN(mem_req) + PAGE_SIZE;
+		screen_base = atari_stram_alloc(mem_req, "atafb");
+		if (!screen_base)
+			panic("Cannot allocate screen memory");
+		memset(screen_base, 0, mem_req);
+		pad = -(unsigned long)screen_base & (PAGE_SIZE-1);
+		screen_base+=pad;
+		real_screen_base=screen_base+ovsc_offset;
+		screen_len = (mem_req - pad - ovsc_offset) & PAGE_MASK;
+		st_ovsc_switch();
+		if (CPU_IS_040_OR_060) {
+			/* On a '040+, the cache mode of video RAM must be set to
+			 * write-through also for internal video hardware! */
+			cache_push(virt_to_phys(screen_base), screen_len);
+			kernel_set_cachemode(screen_base, screen_len,
+					     IOMAP_WRITETHROUGH);
+		}
+#ifdef ATAFB_EXT
+	}
+	else {
+		/* Map the video memory (physical address given) to somewhere
+		 * in the kernel address space.
+		 */
+		external_addr =
+		  ioremap_writethrough((unsigned long)external_addr,
+				       external_len);
+		if (external_vgaiobase)
+			external_vgaiobase =
+			  (unsigned long)ioremap(external_vgaiobase, 0x10000);
+		screen_base      =
+		real_screen_base = external_addr;
+		screen_len       = external_len & PAGE_MASK;
+		memset (screen_base, 0, external_len);
+	}
+#endif /* ATAFB_EXT */
+
+	strcpy(fb_info.modename, "Atari Builtin ");
+	fb_info.changevar = NULL;
+	fb_info.fbops = &atafb_ops;
+	fb_info.disp = &disp;
+	fb_info.currcon = -1;
+	fb_info.switch_con = &atafb_switch;
+	fb_info.updatevar = &fb_update_var;
+	fb_info.flags = FBINFO_FLAG_DEFAULT;
+	do_fb_set_var(&atafb_predefined[default_par-1], 1);
+	strcat(fb_info.modename, fb_var_names[default_par-1][0]);
+
+	atafb_get_var(&disp.var, -1, &fb_info);
+	atafb_set_disp(-1, &fb_info);
+	do_install_cmap(0, &fb_info);
+
+	if (register_framebuffer(&fb_info) < 0)
+		return -EINVAL;
+
+	printk("Determined %dx%d, depth %d\n",
+	       disp.var.xres, disp.var.yres, disp.var.bits_per_pixel);
+	if ((disp.var.xres != disp.var.xres_virtual) ||
+	    (disp.var.yres != disp.var.yres_virtual))
+	   printk("   virtual %dx%d\n",
+			  disp.var.xres_virtual, disp.var.yres_virtual);
+	printk("fb%d: %s frame buffer device, using %dK of video memory\n",
+	       fb_info.node, fb_info.modename, screen_len>>10);
+
+	/* TODO: This driver cannot be unloaded yet */
+	return 0;
+}
+
+
+#ifdef ATAFB_EXT
+static void __init atafb_setup_ext(char *spec)
+{
+	int		xres, xres_virtual, yres, depth, planes;
+	unsigned long addr, len;
+	char *p;
+
+	/* Format is: <xres>;<yres>;<depth>;<plane organ.>;
+	 *            <screen mem addr>
+	 *	      [;<screen mem length>[;<vgaiobase>[;<bits-per-col>[;<colorreg-type>
+	 *	      [;<xres-virtual>]]]]]
+	 *
+	 * 09/23/97	Juergen
+	 * <xres_virtual>:	hardware's x-resolution (f.e. ProMST)
+	 *
+	 * Even xres_virtual is available, we neither support panning nor hw-scrolling!
+	 */
+	if (!(p = strsep(&spec, ";")) || !*p)
+	    return;
+	xres_virtual = xres = simple_strtoul(p, NULL, 10);
+	if (xres <= 0)
+	    return;
+
+	if (!(p = strsep(&spec, ";")) || !*p)
+	    return;
+	yres = simple_strtoul(p, NULL, 10);
+	if (yres <= 0)
+	    return;
+
+	if (!(p = strsep(&spec, ";")) || !*p)
+	    return;
+	depth = simple_strtoul(p, NULL, 10);
+	if (depth != 1 && depth != 2 && depth != 4 && depth != 8 &&
+		depth != 16 && depth != 24)
+	    return;
+
+	if (!(p = strsep(&spec, ";")) || !*p)
+	    return;
+	if (*p == 'i')
+		planes = FB_TYPE_INTERLEAVED_PLANES;
+	else if (*p == 'p')
+		planes = FB_TYPE_PACKED_PIXELS;
+	else if (*p == 'n')
+		planes = FB_TYPE_PLANES;
+	else if (*p == 't')
+		planes = -1; /* true color */
+	else
+		return;
+
+
+	if (!(p = strsep(&spec, ";")) || !*p)
+		return;
+	addr = simple_strtoul(p, NULL, 0);
+
+	if (!(p = strsep(&spec, ";")) || !*p)
+		len = xres*yres*depth/8;
+	else
+		len = simple_strtoul(p, NULL, 0);
+
+	if ((p = strsep(&spec, ";")) && *p) {
+		external_vgaiobase=simple_strtoul(p, NULL, 0);
+	}
+
+	if ((p = strsep(&spec, ";")) && *p) {
+		external_bitspercol = simple_strtoul(p, NULL, 0);
+		if (external_bitspercol > 8)
+			external_bitspercol = 8;
+		else if (external_bitspercol < 1)
+			external_bitspercol = 1;
+	}
+
+	if ((p = strsep(&spec, ";")) && *p) {
+		if (!strcmp(p, "vga"))
+			external_card_type = IS_VGA;
+		if (!strcmp(p, "mv300"))
+			external_card_type = IS_MV300;
+	}
+
+	if ((p = strsep(&spec, ";")) && *p) {
+		xres_virtual = simple_strtoul(p, NULL, 10);
+		if (xres_virtual < xres)
+			xres_virtual = xres;
+		if (xres_virtual*yres*depth/8 > len)
+			len=xres_virtual*yres*depth/8;
+	}
+
+	external_xres  = xres;
+	external_xres_virtual  = xres_virtual;
+	external_yres  = yres;
+	external_depth = depth;
+	external_pmode = planes;
+	external_addr  = (void *)addr;
+	external_len   = len;
+
+	if (external_card_type == IS_MV300)
+	  switch (external_depth) {
+	    case 1:
+	      MV300_reg = MV300_reg_1bit;
+	      break;
+	    case 4:
+	      MV300_reg = MV300_reg_4bit;
+	      break;
+	    case 8:
+	      MV300_reg = MV300_reg_8bit;
+	      break;
+	    }
+}
+#endif /* ATAFB_EXT */
+
+
+static void __init atafb_setup_int(char *spec)
+{
+	/* Format to config extended internal video hardware like OverScan:
+	"internal:<xres>;<yres>;<xres_max>;<yres_max>;<offset>"
+	Explanation:
+	<xres>: x-resolution 
+	<yres>: y-resolution
+	The following are only needed if you have an overscan which
+	needs a black border:
+	<xres_max>: max. length of a line in pixels your OverScan hardware would allow
+	<yres_max>: max. number of lines your OverScan hardware would allow
+	<offset>: Offset from physical beginning to visible beginning
+		  of screen in bytes
+	*/
+	int xres;
+	char *p;
+
+	if (!(p = strsep(&spec, ";")) || !*p)
+		return;
+	xres = simple_strtoul(p, NULL, 10);
+	if (!(p = strsep(&spec, ";")) || !*p)
+		return;
+	sttt_xres=xres;
+	tt_yres=st_yres=simple_strtoul(p, NULL, 10);
+	if ((p=strsep(&spec, ";")) && *p) {
+		sttt_xres_virtual=simple_strtoul(p, NULL, 10);
+	}
+	if ((p=strsep(&spec, ";")) && *p) {
+		sttt_yres_virtual=simple_strtoul(p, NULL, 0);
+	}
+	if ((p=strsep(&spec, ";")) && *p) {
+		ovsc_offset=simple_strtoul(p, NULL, 0);
+	}
+
+	if (ovsc_offset || (sttt_yres_virtual != st_yres))
+		use_hwscroll=0;
+}
+
+
+#ifdef ATAFB_FALCON
+static void __init atafb_setup_mcap(char *spec)
+{
+	char *p;
+	int vmin, vmax, hmin, hmax;
+
+	/* Format for monitor capabilities is: <Vmin>;<Vmax>;<Hmin>;<Hmax>
+	 * <V*> vertical freq. in Hz
+	 * <H*> horizontal freq. in kHz
+	 */
+	if (!(p = strsep(&spec, ";")) || !*p)
+		return;
+	vmin = simple_strtoul(p, NULL, 10);
+	if (vmin <= 0)
+		return;
+	if (!(p = strsep(&spec, ";")) || !*p)
+		return;
+	vmax = simple_strtoul(p, NULL, 10);
+	if (vmax <= 0 || vmax <= vmin)
+		return;
+	if (!(p = strsep(&spec, ";")) || !*p)
+		return;
+	hmin = 1000 * simple_strtoul(p, NULL, 10);
+	if (hmin <= 0)
+		return;
+	if (!(p = strsep(&spec, "")) || !*p)
+		return;
+	hmax = 1000 * simple_strtoul(p, NULL, 10);
+	if (hmax <= 0 || hmax <= hmin)
+		return;
+
+	fb_info.monspecs.vfmin = vmin;
+	fb_info.monspecs.vfmax = vmax;
+	fb_info.monspecs.hfmin = hmin;
+	fb_info.monspecs.hfmax = hmax;
+}
+#endif /* ATAFB_FALCON */
+
+
+static void __init atafb_setup_user(char *spec)
+{
+	/* Format of user defined video mode is: <xres>;<yres>;<depth>
+	 */
+	char *p;
+	int xres, yres, depth, temp;
+
+	if (!(p = strsep(&spec, ";")) || !*p)
+		return;
+	xres = simple_strtoul(p, NULL, 10);
+	if (!(p = strsep(&spec, ";")) || !*p)
+		return;
+	yres = simple_strtoul(p, NULL, 10);
+	if (!(p = strsep(&spec, "")) || !*p)
+		return;
+	depth = simple_strtoul(p, NULL, 10);
+	if ((temp=get_video_mode("user0"))) {
+		default_par=temp;
+		atafb_predefined[default_par-1].xres = xres;
+		atafb_predefined[default_par-1].yres = yres;
+		atafb_predefined[default_par-1].bits_per_pixel = depth;
+	}
+}
+
+int __init atafb_setup( char *options )
+{
+    char *this_opt;
+    int temp;
+
+    fb_info.fontname[0] = '\0';
+
+    if (!options || !*options)
+		return 0;
+    
+    while ((this_opt = strsep(&options, ",")) != NULL) {	 
+	if (!*this_opt) continue;
+	if ((temp=get_video_mode(this_opt)))
+		default_par=temp;
+	else if (! strcmp(this_opt, "inverse"))
+		inverse=1;
+	else if (!strncmp(this_opt, "font:", 5))
+	   strcpy(fb_info.fontname, this_opt+5);
+	else if (! strncmp(this_opt, "hwscroll_",9)) {
+		hwscroll=simple_strtoul(this_opt+9, NULL, 10);
+		if (hwscroll < 0)
+			hwscroll = 0;
+		if (hwscroll > 200)
+			hwscroll = 200;
+	}
+#ifdef ATAFB_EXT
+	else if (!strcmp(this_opt,"mv300")) {
+		external_bitspercol = 8;
+		external_card_type = IS_MV300;
+	}
+	else if (!strncmp(this_opt,"external:",9))
+		atafb_setup_ext(this_opt+9);
+#endif
+	else if (!strncmp(this_opt,"internal:",9))
+		atafb_setup_int(this_opt+9);
+#ifdef ATAFB_FALCON
+	else if (!strncmp(this_opt, "eclock:", 7)) {
+		fext.f = simple_strtoul(this_opt+7, NULL, 10);
+		/* external pixelclock in kHz --> ps */
+		fext.t = 1000000000/fext.f;
+		fext.f *= 1000;
+	}
+	else if (!strncmp(this_opt, "monitorcap:", 11))
+		atafb_setup_mcap(this_opt+11);
+#endif
+	else if (!strcmp(this_opt, "keep"))
+		DontCalcRes = 1;
+	else if (!strncmp(this_opt, "R", 1))
+		atafb_setup_user(this_opt+1);
+    }
+    return 0;
+}
+
+#ifdef MODULE
+MODULE_LICENSE("GPL");
+
+int init_module(void)
+{
+	return atafb_init();
+}
+#endif /* MODULE */