/*
 * linux/drivers/video/s3fb.c -- Frame buffer device driver for S3 Trio/Virge
 *
 * Copyright (c) 2006-2007 Ondrej Zajicek <santiago@crfreenet.org>
 *
 * 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.
 *
 * Code is based on David Boucher's viafb (http://davesdomain.org.uk/viafb/)
 * which is based on the code of neofb.
 */

#include <linux/version.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/tty.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/fb.h>
#include <linux/svga.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/console.h> /* Why should fb driver call console functions? because acquire_console_sem() */
#include <video/vga.h>

#ifdef CONFIG_MTRR
#include <asm/mtrr.h>
#endif

struct s3fb_info {
	int chip, rev, mclk_freq;
	int mtrr_reg;
	struct vgastate state;
	struct mutex open_lock;
	unsigned int ref_count;
	u32 pseudo_palette[16];
};


/* ------------------------------------------------------------------------- */

static const struct svga_fb_format s3fb_formats[] = {
	{ 0,  {0, 6, 0},  {0, 6, 0},  {0, 6, 0}, {0, 0, 0}, 0,
		FB_TYPE_TEXT, FB_AUX_TEXT_SVGA_STEP4,	FB_VISUAL_PSEUDOCOLOR, 8, 16},
	{ 4,  {0, 6, 0},  {0, 6, 0},  {0, 6, 0}, {0, 0, 0}, 0,
		FB_TYPE_PACKED_PIXELS, 0,		FB_VISUAL_PSEUDOCOLOR, 8, 16},
	{ 4,  {0, 6, 0},  {0, 6, 0},  {0, 6, 0}, {0, 0, 0}, 1,
		FB_TYPE_INTERLEAVED_PLANES, 1,		FB_VISUAL_PSEUDOCOLOR, 8, 16},
	{ 8,  {0, 6, 0},  {0, 6, 0},  {0, 6, 0}, {0, 0, 0}, 0,
		FB_TYPE_PACKED_PIXELS, 0,		FB_VISUAL_PSEUDOCOLOR, 4, 8},
	{16,  {10, 5, 0}, {5, 5, 0},  {0, 5, 0}, {0, 0, 0}, 0,
		FB_TYPE_PACKED_PIXELS, 0,		FB_VISUAL_TRUECOLOR, 2, 4},
	{16,  {11, 5, 0}, {5, 6, 0},  {0, 5, 0}, {0, 0, 0}, 0,
		FB_TYPE_PACKED_PIXELS, 0,		FB_VISUAL_TRUECOLOR, 2, 4},
	{24,  {16, 8, 0}, {8, 8, 0},  {0, 8, 0}, {0, 0, 0}, 0,
		FB_TYPE_PACKED_PIXELS, 0,		FB_VISUAL_TRUECOLOR, 1, 2},
	{32,  {16, 8, 0}, {8, 8, 0},  {0, 8, 0}, {0, 0, 0}, 0,
		FB_TYPE_PACKED_PIXELS, 0,		FB_VISUAL_TRUECOLOR, 1, 2},
	SVGA_FORMAT_END
};


static const struct svga_pll s3_pll = {3, 129, 3, 33, 0, 3,
	60000, 240000, 14318};

static const int s3_memsizes[] = {4096, 0, 3072, 8192, 2048, 6144, 1024, 512};

static const char * const s3_names[] = {"S3 Unknown", "S3 Trio32", "S3 Trio64", "S3 Trio64V+",
			"S3 Trio64UV+", "S3 Trio64V2/DX", "S3 Trio64V2/GX",
			"S3 Plato/PX", "S3 Aurora64VP", "S3 Virge",
			"S3 Virge/VX", "S3 Virge/DX", "S3 Virge/GX",
			"S3 Virge/GX2", "S3 Virge/GX2P", "S3 Virge/GX2P"};

#define CHIP_UNKNOWN		0x00
#define CHIP_732_TRIO32		0x01
#define CHIP_764_TRIO64		0x02
#define CHIP_765_TRIO64VP	0x03
#define CHIP_767_TRIO64UVP	0x04
#define CHIP_775_TRIO64V2_DX	0x05
#define CHIP_785_TRIO64V2_GX	0x06
#define CHIP_551_PLATO_PX	0x07
#define CHIP_M65_AURORA64VP	0x08
#define CHIP_325_VIRGE		0x09
#define CHIP_988_VIRGE_VX	0x0A
#define CHIP_375_VIRGE_DX	0x0B
#define CHIP_385_VIRGE_GX	0x0C
#define CHIP_356_VIRGE_GX2	0x0D
#define CHIP_357_VIRGE_GX2P	0x0E
#define CHIP_359_VIRGE_GX2P	0x0F

#define CHIP_XXX_TRIO		0x80
#define CHIP_XXX_TRIO64V2_DXGX	0x81
#define CHIP_XXX_VIRGE_DXGX	0x82

#define CHIP_UNDECIDED_FLAG	0x80
#define CHIP_MASK		0xFF

/* CRT timing register sets */

static const struct vga_regset s3_h_total_regs[]        = {{0x00, 0, 7}, {0x5D, 0, 0}, VGA_REGSET_END};
static const struct vga_regset s3_h_display_regs[]      = {{0x01, 0, 7}, {0x5D, 1, 1}, VGA_REGSET_END};
static const struct vga_regset s3_h_blank_start_regs[]  = {{0x02, 0, 7}, {0x5D, 2, 2}, VGA_REGSET_END};
static const struct vga_regset s3_h_blank_end_regs[]    = {{0x03, 0, 4}, {0x05, 7, 7}, VGA_REGSET_END};
static const struct vga_regset s3_h_sync_start_regs[]   = {{0x04, 0, 7}, {0x5D, 4, 4}, VGA_REGSET_END};
static const struct vga_regset s3_h_sync_end_regs[]     = {{0x05, 0, 4}, VGA_REGSET_END};

static const struct vga_regset s3_v_total_regs[]        = {{0x06, 0, 7}, {0x07, 0, 0}, {0x07, 5, 5}, {0x5E, 0, 0}, VGA_REGSET_END};
static const struct vga_regset s3_v_display_regs[]      = {{0x12, 0, 7}, {0x07, 1, 1}, {0x07, 6, 6}, {0x5E, 1, 1}, VGA_REGSET_END};
static const struct vga_regset s3_v_blank_start_regs[]  = {{0x15, 0, 7}, {0x07, 3, 3}, {0x09, 5, 5}, {0x5E, 2, 2}, VGA_REGSET_END};
static const struct vga_regset s3_v_blank_end_regs[]    = {{0x16, 0, 7}, VGA_REGSET_END};
static const struct vga_regset s3_v_sync_start_regs[]   = {{0x10, 0, 7}, {0x07, 2, 2}, {0x07, 7, 7}, {0x5E, 4, 4}, VGA_REGSET_END};
static const struct vga_regset s3_v_sync_end_regs[]     = {{0x11, 0, 3}, VGA_REGSET_END};

static const struct vga_regset s3_line_compare_regs[]   = {{0x18, 0, 7}, {0x07, 4, 4}, {0x09, 6, 6}, {0x5E, 6, 6}, VGA_REGSET_END};
static const struct vga_regset s3_start_address_regs[]  = {{0x0d, 0, 7}, {0x0c, 0, 7}, {0x31, 4, 5}, {0x51, 0, 1}, VGA_REGSET_END};
static const struct vga_regset s3_offset_regs[]         = {{0x13, 0, 7}, {0x51, 4, 5}, VGA_REGSET_END}; /* set 0x43 bit 2 to 0 */

static const struct svga_timing_regs s3_timing_regs     = {
	s3_h_total_regs, s3_h_display_regs, s3_h_blank_start_regs,
	s3_h_blank_end_regs, s3_h_sync_start_regs, s3_h_sync_end_regs,
	s3_v_total_regs, s3_v_display_regs, s3_v_blank_start_regs,
	s3_v_blank_end_regs, s3_v_sync_start_regs, s3_v_sync_end_regs,
};


/* ------------------------------------------------------------------------- */

/* Module parameters */


static char *mode = "640x480-8@60";

#ifdef CONFIG_MTRR
static int mtrr = 1;
#endif

static int fasttext = 1;


MODULE_AUTHOR("(c) 2006-2007 Ondrej Zajicek <santiago@crfreenet.org>");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("fbdev driver for S3 Trio/Virge");

module_param(mode, charp, 0444);
MODULE_PARM_DESC(mode, "Default video mode ('640x480-8@60', etc)");

#ifdef CONFIG_MTRR
module_param(mtrr, int, 0444);
MODULE_PARM_DESC(mtrr, "Enable write-combining with MTRR (1=enable, 0=disable, default=1)");
#endif

module_param(fasttext, int, 0644);
MODULE_PARM_DESC(fasttext, "Enable S3 fast text mode (1=enable, 0=disable, default=1)");


/* ------------------------------------------------------------------------- */

/* Set font in S3 fast text mode */

static void s3fb_settile_fast(struct fb_info *info, struct fb_tilemap *map)
{
	const u8 *font = map->data;
	u8 __iomem *fb = (u8 __iomem *) info->screen_base;
	int i, c;

	if ((map->width != 8) || (map->height != 16) ||
	    (map->depth != 1) || (map->length != 256)) {
	    	printk(KERN_ERR "fb%d: unsupported font parameters: width %d, height %d, depth %d, length %d\n",
			info->node, map->width, map->height, map->depth, map->length);
		return;
	}

	fb += 2;
	for (i = 0; i < map->height; i++) {
		for (c = 0; c < map->length; c++) {
			fb_writeb(font[c * map->height + i], fb + c * 4);
		}
		fb += 1024;
	}
}

static int s3fb_get_tilemax(struct fb_info *info)
{
	return 256;
}

static struct fb_tile_ops s3fb_tile_ops = {
	.fb_settile	= svga_settile,
	.fb_tilecopy	= svga_tilecopy,
	.fb_tilefill    = svga_tilefill,
	.fb_tileblit    = svga_tileblit,
	.fb_tilecursor  = svga_tilecursor,
	.fb_get_tilemax = s3fb_get_tilemax,
};

static struct fb_tile_ops s3fb_fast_tile_ops = {
	.fb_settile	= s3fb_settile_fast,
	.fb_tilecopy	= svga_tilecopy,
	.fb_tilefill    = svga_tilefill,
	.fb_tileblit    = svga_tileblit,
	.fb_tilecursor  = svga_tilecursor,
	.fb_get_tilemax = s3fb_get_tilemax,
};


/* ------------------------------------------------------------------------- */

/* image data is MSB-first, fb structure is MSB-first too */
static inline u32 expand_color(u32 c)
{
	return ((c & 1) | ((c & 2) << 7) | ((c & 4) << 14) | ((c & 8) << 21)) * 0xFF;
}

/* s3fb_iplan_imageblit silently assumes that almost everything is 8-pixel aligned */
static void s3fb_iplan_imageblit(struct fb_info *info, const struct fb_image *image)
{
	u32 fg = expand_color(image->fg_color);
	u32 bg = expand_color(image->bg_color);
	const u8 *src1, *src;
	u8 __iomem *dst1;
	u32 __iomem *dst;
	u32 val;
	int x, y;

	src1 = image->data;
	dst1 = info->screen_base + (image->dy * info->fix.line_length)
		 + ((image->dx / 8) * 4);

	for (y = 0; y < image->height; y++) {
		src = src1;
		dst = (u32 __iomem *) dst1;
		for (x = 0; x < image->width; x += 8) {
			val = *(src++) * 0x01010101;
			val = (val & fg) | (~val & bg);
			fb_writel(val, dst++);
		}
		src1 += image->width / 8;
		dst1 += info->fix.line_length;
	}

}

/* s3fb_iplan_fillrect silently assumes that almost everything is 8-pixel aligned */
static void s3fb_iplan_fillrect(struct fb_info *info, const struct fb_fillrect *rect)
{
	u32 fg = expand_color(rect->color);
	u8 __iomem *dst1;
	u32 __iomem *dst;
	int x, y;

	dst1 = info->screen_base + (rect->dy * info->fix.line_length)
		 + ((rect->dx / 8) * 4);

	for (y = 0; y < rect->height; y++) {
		dst = (u32 __iomem *) dst1;
		for (x = 0; x < rect->width; x += 8) {
			fb_writel(fg, dst++);
		}
		dst1 += info->fix.line_length;
	}
}


/* image data is MSB-first, fb structure is high-nibble-in-low-byte-first */
static inline u32 expand_pixel(u32 c)
{
	return (((c &  1) << 24) | ((c &  2) << 27) | ((c &  4) << 14) | ((c &   8) << 17) |
		((c & 16) <<  4) | ((c & 32) <<  7) | ((c & 64) >>  6) | ((c & 128) >>  3)) * 0xF;
}

/* s3fb_cfb4_imageblit silently assumes that almost everything is 8-pixel aligned */
static void s3fb_cfb4_imageblit(struct fb_info *info, const struct fb_image *image)
{
	u32 fg = image->fg_color * 0x11111111;
	u32 bg = image->bg_color * 0x11111111;
	const u8 *src1, *src;
	u8 __iomem *dst1;
	u32 __iomem *dst;
	u32 val;
	int x, y;

	src1 = image->data;
	dst1 = info->screen_base + (image->dy * info->fix.line_length)
		 + ((image->dx / 8) * 4);

	for (y = 0; y < image->height; y++) {
		src = src1;
		dst = (u32 __iomem *) dst1;
		for (x = 0; x < image->width; x += 8) {
			val = expand_pixel(*(src++));
			val = (val & fg) | (~val & bg);
			fb_writel(val, dst++);
		}
		src1 += image->width / 8;
		dst1 += info->fix.line_length;
	}
}

static void s3fb_imageblit(struct fb_info *info, const struct fb_image *image)
{
	if ((info->var.bits_per_pixel == 4) && (image->depth == 1)
	    && ((image->width % 8) == 0) && ((image->dx % 8) == 0)) {
		if (info->fix.type == FB_TYPE_INTERLEAVED_PLANES)
			s3fb_iplan_imageblit(info, image);
		else
			s3fb_cfb4_imageblit(info, image);
	} else
		cfb_imageblit(info, image);
}

static void s3fb_fillrect(struct fb_info *info, const struct fb_fillrect *rect)
{
	if ((info->var.bits_per_pixel == 4)
	    && ((rect->width % 8) == 0) && ((rect->dx % 8) == 0)
	    && (info->fix.type == FB_TYPE_INTERLEAVED_PLANES))
		s3fb_iplan_fillrect(info, rect);
	 else
		cfb_fillrect(info, rect);
}


/* ------------------------------------------------------------------------- */


static void s3_set_pixclock(struct fb_info *info, u32 pixclock)
{
	u16 m, n, r;
	u8 regval;

	svga_compute_pll(&s3_pll, 1000000000 / pixclock, &m, &n, &r, info->node);

	/* Set VGA misc register  */
	regval = vga_r(NULL, VGA_MIS_R);
	vga_w(NULL, VGA_MIS_W, regval | VGA_MIS_ENB_PLL_LOAD);

	/* Set S3 clock registers */
	vga_wseq(NULL, 0x12, ((n - 2) | (r << 5)));
	vga_wseq(NULL, 0x13, m - 2);

	udelay(1000);

	/* Activate clock - write 0, 1, 0 to seq/15 bit 5 */
	regval = vga_rseq (NULL, 0x15); /* | 0x80; */
	vga_wseq(NULL, 0x15, regval & ~(1<<5));
	vga_wseq(NULL, 0x15, regval |  (1<<5));
	vga_wseq(NULL, 0x15, regval & ~(1<<5));
}


/* Open framebuffer */

static int s3fb_open(struct fb_info *info, int user)
{
	struct s3fb_info *par = info->par;

	mutex_lock(&(par->open_lock));
	if (par->ref_count == 0) {
		memset(&(par->state), 0, sizeof(struct vgastate));
		par->state.flags = VGA_SAVE_MODE | VGA_SAVE_FONTS | VGA_SAVE_CMAP;
		par->state.num_crtc = 0x70;
		par->state.num_seq = 0x20;
		save_vga(&(par->state));
	}

	par->ref_count++;
	mutex_unlock(&(par->open_lock));

	return 0;
}

/* Close framebuffer */

static int s3fb_release(struct fb_info *info, int user)
{
	struct s3fb_info *par = info->par;

	mutex_lock(&(par->open_lock));
	if (par->ref_count == 0) {
		mutex_unlock(&(par->open_lock));
		return -EINVAL;
	}

	if (par->ref_count == 1)
		restore_vga(&(par->state));

	par->ref_count--;
	mutex_unlock(&(par->open_lock));

	return 0;
}

/* Validate passed in var */

static int s3fb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
{
	struct s3fb_info *par = info->par;
	int rv, mem, step;

	/* Find appropriate format */
	rv = svga_match_format (s3fb_formats, var, NULL);
	if ((rv < 0) || ((par->chip == CHIP_988_VIRGE_VX) ? (rv == 7) : (rv == 6)))
	{		/* 24bpp on VIRGE VX, 32bpp on others */
		printk(KERN_ERR "fb%d: unsupported mode requested\n", info->node);
		return rv;
	}

	/* Do not allow to have real resoulution larger than virtual */
	if (var->xres > var->xres_virtual)
		var->xres_virtual = var->xres;

	if (var->yres > var->yres_virtual)
		var->yres_virtual = var->yres;

	/* Round up xres_virtual to have proper alignment of lines */
	step = s3fb_formats[rv].xresstep - 1;
	var->xres_virtual = (var->xres_virtual+step) & ~step;

	/* Check whether have enough memory */
	mem = ((var->bits_per_pixel * var->xres_virtual) >> 3) * var->yres_virtual;
	if (mem > info->screen_size)
	{
		printk(KERN_ERR "fb%d: not enough framebuffer memory (%d kB requested , %d kB available)\n",
			info->node, mem >> 10, (unsigned int) (info->screen_size >> 10));
		return -EINVAL;
	}

	rv = svga_check_timings (&s3_timing_regs, var, info->node);
	if (rv < 0)
	{
		printk(KERN_ERR "fb%d: invalid timings requested\n", info->node);
		return rv;
	}

	return 0;
}

/* Set video mode from par */

static int s3fb_set_par(struct fb_info *info)
{
	struct s3fb_info *par = info->par;
	u32 value, mode, hmul, offset_value, screen_size, multiplex;
	u32 bpp = info->var.bits_per_pixel;

	if (bpp != 0) {
		info->fix.ypanstep = 1;
		info->fix.line_length = (info->var.xres_virtual * bpp) / 8;

		info->flags &= ~FBINFO_MISC_TILEBLITTING;
		info->tileops = NULL;

		/* supports blit rectangles of any dimension */
		info->pixmap.blit_x = ~(u32)0;
		info->pixmap.blit_y = ~(u32)0;
		offset_value = (info->var.xres_virtual * bpp) / 64;
		screen_size = info->var.yres_virtual * info->fix.line_length;
	} else {
		info->fix.ypanstep = 16;
		info->fix.line_length = 0;

		info->flags |= FBINFO_MISC_TILEBLITTING;
		info->tileops = fasttext ? &s3fb_fast_tile_ops : &s3fb_tile_ops;
		/* supports 8x16 tiles only */
		info->pixmap.blit_x = 1 << (8 - 1);
		info->pixmap.blit_y = 1 << (16 - 1);

		offset_value = info->var.xres_virtual / 16;
		screen_size = (info->var.xres_virtual * info->var.yres_virtual) / 64;
	}

	info->var.xoffset = 0;
	info->var.yoffset = 0;
	info->var.activate = FB_ACTIVATE_NOW;

	/* Unlock registers */
	vga_wcrt(NULL, 0x38, 0x48);
	vga_wcrt(NULL, 0x39, 0xA5);
	vga_wseq(NULL, 0x08, 0x06);
	svga_wcrt_mask(0x11, 0x00, 0x80);

	/* Blank screen and turn off sync */
	svga_wseq_mask(0x01, 0x20, 0x20);
	svga_wcrt_mask(0x17, 0x00, 0x80);

	/* Set default values */
	svga_set_default_gfx_regs();
	svga_set_default_atc_regs();
	svga_set_default_seq_regs();
	svga_set_default_crt_regs();
	svga_wcrt_multi(s3_line_compare_regs, 0xFFFFFFFF);
	svga_wcrt_multi(s3_start_address_regs, 0);

	/* S3 specific initialization */
	svga_wcrt_mask(0x58, 0x10, 0x10); /* enable linear framebuffer */
	svga_wcrt_mask(0x31, 0x08, 0x08); /* enable sequencer access to framebuffer above 256 kB */

/*	svga_wcrt_mask(0x33, 0x08, 0x08); */ /* DDR ?	*/
/*	svga_wcrt_mask(0x43, 0x01, 0x01); */ /* DDR ?	*/
	svga_wcrt_mask(0x33, 0x00, 0x08); /* no DDR ?	*/
	svga_wcrt_mask(0x43, 0x00, 0x01); /* no DDR ?	*/

	svga_wcrt_mask(0x5D, 0x00, 0x28); // Clear strange HSlen bits

/*	svga_wcrt_mask(0x58, 0x03, 0x03); */

/*	svga_wcrt_mask(0x53, 0x12, 0x13); */ /* enable MMIO */
/*	svga_wcrt_mask(0x40, 0x08, 0x08); */ /* enable write buffer */


	/* Set the offset register */
	pr_debug("fb%d: offset register       : %d\n", info->node, offset_value);
	svga_wcrt_multi(s3_offset_regs, offset_value);

	vga_wcrt(NULL, 0x54, 0x18); /* M parameter */
	vga_wcrt(NULL, 0x60, 0xff); /* N parameter */
	vga_wcrt(NULL, 0x61, 0xff); /* L parameter */
	vga_wcrt(NULL, 0x62, 0xff); /* L parameter */

	vga_wcrt(NULL, 0x3A, 0x35);
	svga_wattr(0x33, 0x00);

	if (info->var.vmode & FB_VMODE_DOUBLE)
		svga_wcrt_mask(0x09, 0x80, 0x80);
	else
		svga_wcrt_mask(0x09, 0x00, 0x80);

	if (info->var.vmode & FB_VMODE_INTERLACED)
		svga_wcrt_mask(0x42, 0x20, 0x20);
	else
		svga_wcrt_mask(0x42, 0x00, 0x20);

	/* Disable hardware graphics cursor */
	svga_wcrt_mask(0x45, 0x00, 0x01);
	/* Disable Streams engine */
	svga_wcrt_mask(0x67, 0x00, 0x0C);

	mode = svga_match_format(s3fb_formats, &(info->var), &(info->fix));

	/* S3 virge DX hack */
	if (par->chip == CHIP_375_VIRGE_DX) {
		vga_wcrt(NULL, 0x86, 0x80);
		vga_wcrt(NULL, 0x90, 0x00);
	}

	/* S3 virge VX hack */
	if (par->chip == CHIP_988_VIRGE_VX) {
		vga_wcrt(NULL, 0x50, 0x00);
		vga_wcrt(NULL, 0x67, 0x50);

		vga_wcrt(NULL, 0x63, (mode <= 2) ? 0x90 : 0x09);
		vga_wcrt(NULL, 0x66, 0x90);
	}

	svga_wcrt_mask(0x31, 0x00, 0x40);
	multiplex = 0;
	hmul = 1;

	/* Set mode-specific register values */
	switch (mode) {
	case 0:
		pr_debug("fb%d: text mode\n", info->node);
		svga_set_textmode_vga_regs();

		/* Set additional registers like in 8-bit mode */
		svga_wcrt_mask(0x50, 0x00, 0x30);
		svga_wcrt_mask(0x67, 0x00, 0xF0);

		/* Disable enhanced mode */
		svga_wcrt_mask(0x3A, 0x00, 0x30);

		if (fasttext) {
			pr_debug("fb%d: high speed text mode set\n", info->node);
			svga_wcrt_mask(0x31, 0x40, 0x40);
		}
		break;
	case 1:
		pr_debug("fb%d: 4 bit pseudocolor\n", info->node);
		vga_wgfx(NULL, VGA_GFX_MODE, 0x40);

		/* Set additional registers like in 8-bit mode */
		svga_wcrt_mask(0x50, 0x00, 0x30);
		svga_wcrt_mask(0x67, 0x00, 0xF0);

		/* disable enhanced mode */
		svga_wcrt_mask(0x3A, 0x00, 0x30);
		break;
	case 2:
		pr_debug("fb%d: 4 bit pseudocolor, planar\n", info->node);

		/* Set additional registers like in 8-bit mode */
		svga_wcrt_mask(0x50, 0x00, 0x30);
		svga_wcrt_mask(0x67, 0x00, 0xF0);

		/* disable enhanced mode */
		svga_wcrt_mask(0x3A, 0x00, 0x30);
		break;
	case 3:
		pr_debug("fb%d: 8 bit pseudocolor\n", info->node);
		if (info->var.pixclock > 20000) {
			svga_wcrt_mask(0x50, 0x00, 0x30);
			svga_wcrt_mask(0x67, 0x00, 0xF0);
		} else {
			svga_wcrt_mask(0x50, 0x00, 0x30);
			svga_wcrt_mask(0x67, 0x10, 0xF0);
			multiplex = 1;
		}
		break;
	case 4:
		pr_debug("fb%d: 5/5/5 truecolor\n", info->node);
		if (par->chip == CHIP_988_VIRGE_VX) {
			if (info->var.pixclock > 20000)
				svga_wcrt_mask(0x67, 0x20, 0xF0);
			else
				svga_wcrt_mask(0x67, 0x30, 0xF0);
		} else {
			svga_wcrt_mask(0x50, 0x10, 0x30);
			svga_wcrt_mask(0x67, 0x30, 0xF0);
			hmul = 2;
		}
		break;
	case 5:
		pr_debug("fb%d: 5/6/5 truecolor\n", info->node);
		if (par->chip == CHIP_988_VIRGE_VX) {
			if (info->var.pixclock > 20000)
				svga_wcrt_mask(0x67, 0x40, 0xF0);
			else
				svga_wcrt_mask(0x67, 0x50, 0xF0);
		} else {
			svga_wcrt_mask(0x50, 0x10, 0x30);
			svga_wcrt_mask(0x67, 0x50, 0xF0);
			hmul = 2;
		}
		break;
	case 6:
		/* VIRGE VX case */
		pr_debug("fb%d: 8/8/8 truecolor\n", info->node);
		svga_wcrt_mask(0x67, 0xD0, 0xF0);
		break;
	case 7:
		pr_debug("fb%d: 8/8/8/8 truecolor\n", info->node);
		svga_wcrt_mask(0x50, 0x30, 0x30);
		svga_wcrt_mask(0x67, 0xD0, 0xF0);
		break;
	default:
		printk(KERN_ERR "fb%d: unsupported mode - bug\n", info->node);
		return -EINVAL;
	}

	if (par->chip != CHIP_988_VIRGE_VX) {
		svga_wseq_mask(0x15, multiplex ? 0x10 : 0x00, 0x10);
		svga_wseq_mask(0x18, multiplex ? 0x80 : 0x00, 0x80);
	}

	s3_set_pixclock(info, info->var.pixclock);
	svga_set_timings(&s3_timing_regs, &(info->var), hmul, 1,
			 (info->var.vmode & FB_VMODE_DOUBLE)     ? 2 : 1,
			 (info->var.vmode & FB_VMODE_INTERLACED) ? 2 : 1,
			 hmul, info->node);

	/* Set interlaced mode start/end register */
	value = info->var.xres + info->var.left_margin + info->var.right_margin + info->var.hsync_len;
	value = ((value * hmul) / 8) - 5;
	vga_wcrt(NULL, 0x3C, (value + 1) / 2);

	memset_io(info->screen_base, 0x00, screen_size);
	/* Device and screen back on */
	svga_wcrt_mask(0x17, 0x80, 0x80);
	svga_wseq_mask(0x01, 0x00, 0x20);

	return 0;
}

/* Set a colour register */

static int s3fb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
				u_int transp, struct fb_info *fb)
{
	switch (fb->var.bits_per_pixel) {
	case 0:
	case 4:
		if (regno >= 16)
			return -EINVAL;

		if ((fb->var.bits_per_pixel == 4) &&
		    (fb->var.nonstd == 0)) {
			outb(0xF0, VGA_PEL_MSK);
			outb(regno*16, VGA_PEL_IW);
		} else {
			outb(0x0F, VGA_PEL_MSK);
			outb(regno, VGA_PEL_IW);
		}
		outb(red >> 10, VGA_PEL_D);
		outb(green >> 10, VGA_PEL_D);
		outb(blue >> 10, VGA_PEL_D);
		break;
	case 8:
		if (regno >= 256)
			return -EINVAL;

		outb(0xFF, VGA_PEL_MSK);
		outb(regno, VGA_PEL_IW);
		outb(red >> 10, VGA_PEL_D);
		outb(green >> 10, VGA_PEL_D);
		outb(blue >> 10, VGA_PEL_D);
		break;
	case 16:
		if (regno >= 16)
			return -EINVAL;

		if (fb->var.green.length == 5)
			((u32*)fb->pseudo_palette)[regno] = ((red & 0xF800) >> 1) |
				((green & 0xF800) >> 6) | ((blue & 0xF800) >> 11);
		else if (fb->var.green.length == 6)
			((u32*)fb->pseudo_palette)[regno] = (red & 0xF800) |
				((green & 0xFC00) >> 5) | ((blue & 0xF800) >> 11);
		else return -EINVAL;
		break;
	case 24:
	case 32:
		if (regno >= 16)
			return -EINVAL;

		((u32*)fb->pseudo_palette)[regno] = ((transp & 0xFF00) << 16) | ((red & 0xFF00) << 8) |
			(green & 0xFF00) | ((blue & 0xFF00) >> 8);
		break;
	default:
		return -EINVAL;
	}

	return 0;
}


/* Set the display blanking state */

static int s3fb_blank(int blank_mode, struct fb_info *info)
{
	switch (blank_mode) {
	case FB_BLANK_UNBLANK:
		pr_debug("fb%d: unblank\n", info->node);
		svga_wcrt_mask(0x56, 0x00, 0x06);
		svga_wseq_mask(0x01, 0x00, 0x20);
		break;
	case FB_BLANK_NORMAL:
		pr_debug("fb%d: blank\n", info->node);
		svga_wcrt_mask(0x56, 0x00, 0x06);
		svga_wseq_mask(0x01, 0x20, 0x20);
		break;
	case FB_BLANK_HSYNC_SUSPEND:
		pr_debug("fb%d: hsync\n", info->node);
		svga_wcrt_mask(0x56, 0x02, 0x06);
		svga_wseq_mask(0x01, 0x20, 0x20);
		break;
	case FB_BLANK_VSYNC_SUSPEND:
		pr_debug("fb%d: vsync\n", info->node);
		svga_wcrt_mask(0x56, 0x04, 0x06);
		svga_wseq_mask(0x01, 0x20, 0x20);
		break;
	case FB_BLANK_POWERDOWN:
		pr_debug("fb%d: sync down\n", info->node);
		svga_wcrt_mask(0x56, 0x06, 0x06);
		svga_wseq_mask(0x01, 0x20, 0x20);
		break;
	}

	return 0;
}


/* Pan the display */

static int s3fb_pan_display(struct fb_var_screeninfo *var, struct fb_info *info) {

	unsigned int offset;

	/* Validate the offsets */
	if ((var->xoffset + var->xres) > var->xres_virtual)
		return -EINVAL;
	if ((var->yoffset + var->yres) > var->yres_virtual)
		return -EINVAL;

	/* Calculate the offset */
	if (var->bits_per_pixel == 0) {
		offset = (var->yoffset / 16) * (var->xres_virtual / 2) + (var->xoffset / 2);
		offset = offset >> 2;
	} else {
		offset = (var->yoffset * info->fix.line_length) +
			 (var->xoffset * var->bits_per_pixel / 8);
		offset = offset >> 2;
	}

	/* Set the offset */
	svga_wcrt_multi(s3_start_address_regs, offset);

	return 0;
}

/* ------------------------------------------------------------------------- */

/* Frame buffer operations */

static struct fb_ops s3fb_ops = {
	.owner		= THIS_MODULE,
	.fb_open	= s3fb_open,
	.fb_release	= s3fb_release,
	.fb_check_var	= s3fb_check_var,
	.fb_set_par	= s3fb_set_par,
	.fb_setcolreg	= s3fb_setcolreg,
	.fb_blank	= s3fb_blank,
	.fb_pan_display	= s3fb_pan_display,
	.fb_fillrect	= s3fb_fillrect,
	.fb_copyarea	= cfb_copyarea,
	.fb_imageblit	= s3fb_imageblit,
};

/* ------------------------------------------------------------------------- */

static int __devinit s3_identification(int chip)
{
	if (chip == CHIP_XXX_TRIO) {
		u8 cr30 = vga_rcrt(NULL, 0x30);
		u8 cr2e = vga_rcrt(NULL, 0x2e);
		u8 cr2f = vga_rcrt(NULL, 0x2f);

		if ((cr30 == 0xE0) || (cr30 == 0xE1)) {
			if (cr2e == 0x10)
				return CHIP_732_TRIO32;
			if (cr2e == 0x11) {
				if (! (cr2f & 0x40))
					return CHIP_764_TRIO64;
				else
					return CHIP_765_TRIO64VP;
			}
		}
	}

	if (chip == CHIP_XXX_TRIO64V2_DXGX) {
		u8 cr6f = vga_rcrt(NULL, 0x6f);

		if (! (cr6f & 0x01))
			return CHIP_775_TRIO64V2_DX;
		else
			return CHIP_785_TRIO64V2_GX;
	}

	if (chip == CHIP_XXX_VIRGE_DXGX) {
		u8 cr6f = vga_rcrt(NULL, 0x6f);

		if (! (cr6f & 0x01))
			return CHIP_375_VIRGE_DX;
		else
			return CHIP_385_VIRGE_GX;
	}

	return CHIP_UNKNOWN;
}


/* PCI probe */

static int __devinit s3_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
{
	struct fb_info *info;
	struct s3fb_info *par;
	int rc;
	u8 regval, cr38, cr39;

	/* Ignore secondary VGA device because there is no VGA arbitration */
	if (! svga_primary_device(dev)) {
		dev_info(&(dev->dev), "ignoring secondary device\n");
		return -ENODEV;
	}

	/* Allocate and fill driver data structure */
	info = framebuffer_alloc(sizeof(struct s3fb_info), NULL);
	if (!info) {
		dev_err(&(dev->dev), "cannot allocate memory\n");
		return -ENOMEM;
	}

	par = info->par;
	mutex_init(&par->open_lock);

	info->flags = FBINFO_PARTIAL_PAN_OK | FBINFO_HWACCEL_YPAN;
	info->fbops = &s3fb_ops;

	/* Prepare PCI device */
	rc = pci_enable_device(dev);
	if (rc < 0) {
		dev_err(&(dev->dev), "cannot enable PCI device\n");
		goto err_enable_device;
	}

	rc = pci_request_regions(dev, "s3fb");
	if (rc < 0) {
		dev_err(&(dev->dev), "cannot reserve framebuffer region\n");
		goto err_request_regions;
	}


	info->fix.smem_start = pci_resource_start(dev, 0);
	info->fix.smem_len = pci_resource_len(dev, 0);

	/* Map physical IO memory address into kernel space */
	info->screen_base = pci_iomap(dev, 0, 0);
	if (! info->screen_base) {
		rc = -ENOMEM;
		dev_err(&(dev->dev), "iomap for framebuffer failed\n");
		goto err_iomap;
	}

	/* Unlock regs */
	cr38 = vga_rcrt(NULL, 0x38);
	cr39 = vga_rcrt(NULL, 0x39);
	vga_wseq(NULL, 0x08, 0x06);
	vga_wcrt(NULL, 0x38, 0x48);
	vga_wcrt(NULL, 0x39, 0xA5);

	/* Find how many physical memory there is on card */
	/* 0x36 register is accessible even if other registers are locked */
	regval = vga_rcrt(NULL, 0x36);
	info->screen_size = s3_memsizes[regval >> 5] << 10;
	info->fix.smem_len = info->screen_size;

	par->chip = id->driver_data & CHIP_MASK;
	par->rev = vga_rcrt(NULL, 0x2f);
	if (par->chip & CHIP_UNDECIDED_FLAG)
		par->chip = s3_identification(par->chip);

	/* Find MCLK frequency */
	regval = vga_rseq(NULL, 0x10);
	par->mclk_freq = ((vga_rseq(NULL, 0x11) + 2) * 14318) / ((regval & 0x1F)  + 2);
	par->mclk_freq = par->mclk_freq >> (regval >> 5);

	/* Restore locks */
	vga_wcrt(NULL, 0x38, cr38);
	vga_wcrt(NULL, 0x39, cr39);

	strcpy(info->fix.id, s3_names [par->chip]);
	info->fix.mmio_start = 0;
	info->fix.mmio_len = 0;
	info->fix.type = FB_TYPE_PACKED_PIXELS;
	info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
	info->fix.ypanstep = 0;
	info->fix.accel = FB_ACCEL_NONE;
	info->pseudo_palette = (void*) (par->pseudo_palette);

	/* Prepare startup mode */
	rc = fb_find_mode(&(info->var), info, mode, NULL, 0, NULL, 8);
	if (! ((rc == 1) || (rc == 2))) {
		rc = -EINVAL;
		dev_err(&(dev->dev), "mode %s not found\n", mode);
		goto err_find_mode;
	}

	rc = fb_alloc_cmap(&info->cmap, 256, 0);
	if (rc < 0) {
		dev_err(&(dev->dev), "cannot allocate colormap\n");
		goto err_alloc_cmap;
	}

	rc = register_framebuffer(info);
	if (rc < 0) {
		dev_err(&(dev->dev), "cannot register framebuffer\n");
		goto err_reg_fb;
	}

	printk(KERN_INFO "fb%d: %s on %s, %d MB RAM, %d MHz MCLK\n", info->node, info->fix.id,
		 pci_name(dev), info->fix.smem_len >> 20, (par->mclk_freq + 500) / 1000);

	if (par->chip == CHIP_UNKNOWN)
		printk(KERN_INFO "fb%d: unknown chip, CR2D=%x, CR2E=%x, CRT2F=%x, CRT30=%x\n",
			info->node, vga_rcrt(NULL, 0x2d), vga_rcrt(NULL, 0x2e),
			vga_rcrt(NULL, 0x2f), vga_rcrt(NULL, 0x30));

	/* Record a reference to the driver data */
	pci_set_drvdata(dev, info);

#ifdef CONFIG_MTRR
	if (mtrr) {
		par->mtrr_reg = -1;
		par->mtrr_reg = mtrr_add(info->fix.smem_start, info->fix.smem_len, MTRR_TYPE_WRCOMB, 1);
	}
#endif

	return 0;

	/* Error handling */
err_reg_fb:
	fb_dealloc_cmap(&info->cmap);
err_alloc_cmap:
err_find_mode:
	pci_iounmap(dev, info->screen_base);
err_iomap:
	pci_release_regions(dev);
err_request_regions:
/*	pci_disable_device(dev); */
err_enable_device:
	framebuffer_release(info);
	return rc;
}


/* PCI remove */

static void __devexit s3_pci_remove(struct pci_dev *dev)
{
	struct fb_info *info = pci_get_drvdata(dev);

	if (info) {

#ifdef CONFIG_MTRR
		struct s3fb_info *par = info->par;

		if (par->mtrr_reg >= 0) {
			mtrr_del(par->mtrr_reg, 0, 0);
			par->mtrr_reg = -1;
		}
#endif

		unregister_framebuffer(info);
		fb_dealloc_cmap(&info->cmap);

		pci_iounmap(dev, info->screen_base);
		pci_release_regions(dev);
/*		pci_disable_device(dev); */

		pci_set_drvdata(dev, NULL);
		framebuffer_release(info);
	}
}

/* PCI suspend */

static int s3_pci_suspend(struct pci_dev* dev, pm_message_t state)
{
	struct fb_info *info = pci_get_drvdata(dev);
	struct s3fb_info *par = info->par;

	dev_info(&(dev->dev), "suspend\n");

	acquire_console_sem();
	mutex_lock(&(par->open_lock));

	if ((state.event == PM_EVENT_FREEZE) || (par->ref_count == 0)) {
		mutex_unlock(&(par->open_lock));
		release_console_sem();
		return 0;
	}

	fb_set_suspend(info, 1);

	pci_save_state(dev);
	pci_disable_device(dev);
	pci_set_power_state(dev, pci_choose_state(dev, state));

	mutex_unlock(&(par->open_lock));
	release_console_sem();

	return 0;
}


/* PCI resume */

static int s3_pci_resume(struct pci_dev* dev)
{
	struct fb_info *info = pci_get_drvdata(dev);
	struct s3fb_info *par = info->par;
	int err;

	dev_info(&(dev->dev), "resume\n");

	acquire_console_sem();
	mutex_lock(&(par->open_lock));

	if (par->ref_count == 0) {
		mutex_unlock(&(par->open_lock));
		release_console_sem();
		return 0;
	}

	pci_set_power_state(dev, PCI_D0);
	pci_restore_state(dev);
	err = pci_enable_device(dev);
	if (err) {
		mutex_unlock(&(par->open_lock));
		release_console_sem();
		dev_err(&(dev->dev), "error %d enabling device for resume\n", err);
		return err;
	}
	pci_set_master(dev);

	s3fb_set_par(info);
	fb_set_suspend(info, 0);

	mutex_unlock(&(par->open_lock));
	release_console_sem();

	return 0;
}


/* List of boards that we are trying to support */

static struct pci_device_id s3_devices[] __devinitdata = {
	{PCI_DEVICE(PCI_VENDOR_ID_S3, 0x8810), .driver_data = CHIP_XXX_TRIO},
	{PCI_DEVICE(PCI_VENDOR_ID_S3, 0x8811), .driver_data = CHIP_XXX_TRIO},
	{PCI_DEVICE(PCI_VENDOR_ID_S3, 0x8812), .driver_data = CHIP_M65_AURORA64VP},
	{PCI_DEVICE(PCI_VENDOR_ID_S3, 0x8814), .driver_data = CHIP_767_TRIO64UVP},
	{PCI_DEVICE(PCI_VENDOR_ID_S3, 0x8901), .driver_data = CHIP_XXX_TRIO64V2_DXGX},
	{PCI_DEVICE(PCI_VENDOR_ID_S3, 0x8902), .driver_data = CHIP_551_PLATO_PX},

	{PCI_DEVICE(PCI_VENDOR_ID_S3, 0x5631), .driver_data = CHIP_325_VIRGE},
	{PCI_DEVICE(PCI_VENDOR_ID_S3, 0x883D), .driver_data = CHIP_988_VIRGE_VX},
	{PCI_DEVICE(PCI_VENDOR_ID_S3, 0x8A01), .driver_data = CHIP_XXX_VIRGE_DXGX},
	{PCI_DEVICE(PCI_VENDOR_ID_S3, 0x8A10), .driver_data = CHIP_356_VIRGE_GX2},
	{PCI_DEVICE(PCI_VENDOR_ID_S3, 0x8A11), .driver_data = CHIP_357_VIRGE_GX2P},
	{PCI_DEVICE(PCI_VENDOR_ID_S3, 0x8A12), .driver_data = CHIP_359_VIRGE_GX2P},

	{0, 0, 0, 0, 0, 0, 0}
};


MODULE_DEVICE_TABLE(pci, s3_devices);

static struct pci_driver s3fb_pci_driver = {
	.name		= "s3fb",
	.id_table	= s3_devices,
	.probe		= s3_pci_probe,
	.remove		= __devexit_p(s3_pci_remove),
	.suspend	= s3_pci_suspend,
	.resume		= s3_pci_resume,
};

/* Parse user speficied options */

#ifndef MODULE
static int  __init s3fb_setup(char *options)
{
	char *opt;

	if (!options || !*options)
		return 0;

	while ((opt = strsep(&options, ",")) != NULL) {

		if (!*opt)
			continue;
#ifdef CONFIG_MTRR
		else if (!strncmp(opt, "mtrr:", 5))
			mtrr = simple_strtoul(opt + 5, NULL, 0);
#endif
		else if (!strncmp(opt, "fasttext:", 9))
			fasttext = simple_strtoul(opt + 9, NULL, 0);
		else
			mode = opt;
	}

	return 0;
}
#endif

/* Cleanup */

static void __exit s3fb_cleanup(void)
{
	pr_debug("s3fb: cleaning up\n");
	pci_unregister_driver(&s3fb_pci_driver);
}

/* Driver Initialisation */

static int __init s3fb_init(void)
{

#ifndef MODULE
	char *option = NULL;

	if (fb_get_options("s3fb", &option))
		return -ENODEV;
	s3fb_setup(option);
#endif

	pr_debug("s3fb: initializing\n");
	return pci_register_driver(&s3fb_pci_driver);
}

/* ------------------------------------------------------------------------- */

/* Modularization */

module_init(s3fb_init);
module_exit(s3fb_cleanup);