/*
   * framebuffer driver for VBE 2.0 compliant graphic boards
   *
   * switching to graphics mode happens at boot time (while
   * running in real mode, see arch/i386/boot/video.S).
   *
   * (c) 1998 Gerd Knorr <kraxel@goldbach.in-berlin.de>
   *
   */
  
  #include <linux/module.h>
  #include <linux/kernel.h>
  #include <linux/errno.h>
  #include <linux/string.h>
  #include <linux/mm.h>

  #include <linux/delay.h>
  #include <linux/fb.h>
  #include <linux/ioport.h>
  #include <linux/init.h>

  #include <linux/platform_device.h>

  #include <linux/screen_info.h>

  #include <video/vga.h>

  #include <asm/io.h>
  #include <asm/mtrr.h>
  
  #define dac_reg	(0x3c8)
  #define dac_val	(0x3c9)
  
  /* --------------------------------------------------------------------- */
  
  static struct fb_var_screeninfo vesafb_defined __initdata = {
  	.activate	= FB_ACTIVATE_NOW,
  	.height		= -1,
  	.width		= -1,
  	.right_margin	= 32,
  	.upper_margin	= 16,
  	.lower_margin	= 4,
  	.vsync_len	= 4,
  	.vmode		= FB_VMODE_NONINTERLACED,
  };
  
  static struct fb_fix_screeninfo vesafb_fix __initdata = {
  	.id	= "VESA VGA",
  	.type	= FB_TYPE_PACKED_PIXELS,
  	.accel	= FB_ACCEL_NONE,
  };

  static int   inverse    __read_mostly;
  static int   mtrr       __read_mostly;		/* disable mtrr */
  static int   vram_remap __initdata;		/* Set amount of memory to be used */
  static int   vram_total __initdata;		/* Set total amount of memory */
  static int   pmi_setpal __read_mostly = 1;	/* pmi for palette changes ??? */
  static int   ypan       __read_mostly;		/* 0..nothing, 1..ypan, 2..ywrap */
  static void  (*pmi_start)(void) __read_mostly;
  static void  (*pmi_pal)  (void) __read_mostly;
  static int   depth      __read_mostly;
  static int   vga_compat __read_mostly;

  /* --------------------------------------------------------------------- */
  
  static int vesafb_pan_display(struct fb_var_screeninfo *var,
                                struct fb_info *info)
  {
  #ifdef __i386__
  	int offset;

  	offset = (var->yoffset * info->fix.line_length + var->xoffset) / 4;
  
          __asm__ __volatile__(
                  "call *(%%edi)"
                  : /* no return value */
                  : "a" (0x4f07),         /* EAX */
                    "b" (0),              /* EBX */
                    "c" (offset),         /* ECX */
                    "d" (offset >> 16),   /* EDX */
                    "D" (&pmi_start));    /* EDI */
  #endif
  	return 0;
  }

  static int vesa_setpalette(int regno, unsigned red, unsigned green,

  			    unsigned blue)
  {

  	int shift = 16 - depth;

  	int err = -EINVAL;

  /*
   * Try VGA registers first...
   */
  	if (vga_compat) {
  		outb_p(regno,       dac_reg);
  		outb_p(red   >> shift, dac_val);
  		outb_p(green >> shift, dac_val);
  		outb_p(blue  >> shift, dac_val);
  		err = 0;
  	}

  #ifdef __i386__

  /*
   * Fallback to the PMI....
   */
  	if (err && pmi_setpal) {
  		struct { u_char blue, green, red, pad; } entry;

  		entry.red   = red   >> shift;
  		entry.green = green >> shift;
  		entry.blue  = blue  >> shift;
  		entry.pad   = 0;
  	        __asm__ __volatile__(
                  "call *(%%esi)"
                  : /* no return value */
                  : "a" (0x4f09),         /* EAX */
                    "b" (0),              /* EBX */
                    "c" (1),              /* ECX */
                    "d" (regno),          /* EDX */
                    "D" (&entry),         /* EDI */
                    "S" (&pmi_pal));      /* ESI */

  		err = 0;

  	}
  #endif

  	return err;

  }
  
  static int vesafb_setcolreg(unsigned regno, unsigned red, unsigned green,
  			    unsigned blue, unsigned transp,
  			    struct fb_info *info)
  {

  	int err = 0;

  	/*
  	 *  Set a single color register. The values supplied are
  	 *  already rounded down to the hardware's capabilities
  	 *  (according to the entries in the `var' structure). Return
  	 *  != 0 for invalid regno.
  	 */
  	
  	if (regno >= info->cmap.len)
  		return 1;

  	if (info->var.bits_per_pixel == 8)

  		err = vesa_setpalette(regno,red,green,blue);

  	else if (regno < 16) {
  		switch (info->var.bits_per_pixel) {
  		case 16:
  			if (info->var.red.offset == 10) {
  				/* 1:5:5:5 */
  				((u32*) (info->pseudo_palette))[regno] =

  					((red   & 0xf800) >>  1) |
  					((green & 0xf800) >>  6) |
  					((blue  & 0xf800) >> 11);

  			} else {
  				/* 0:5:6:5 */
  				((u32*) (info->pseudo_palette))[regno] =

  					((red   & 0xf800)      ) |
  					((green & 0xfc00) >>  5) |
  					((blue  & 0xf800) >> 11);

  			}
  			break;
  		case 24:
  		case 32:
  			red   >>= 8;
  			green >>= 8;
  			blue  >>= 8;
  			((u32 *)(info->pseudo_palette))[regno] =
  				(red   << info->var.red.offset)   |
  				(green << info->var.green.offset) |
  				(blue  << info->var.blue.offset);
  			break;

  		}

  	}

  	return err;

  }

  static void vesafb_destroy(struct fb_info *info)
  {

  	fb_dealloc_cmap(&info->cmap);

  	if (info->screen_base)
  		iounmap(info->screen_base);

  	release_mem_region(info->apertures->ranges[0].base, info->apertures->ranges[0].size);

  	framebuffer_release(info);
  }

  static struct fb_ops vesafb_ops = {
  	.owner		= THIS_MODULE,

  	.fb_destroy     = vesafb_destroy,

  	.fb_setcolreg	= vesafb_setcolreg,
  	.fb_pan_display	= vesafb_pan_display,
  	.fb_fillrect	= cfb_fillrect,
  	.fb_copyarea	= cfb_copyarea,
  	.fb_imageblit	= cfb_imageblit,

  };
  
  static int __init vesafb_setup(char *options)
  {
  	char *this_opt;
  	
  	if (!options || !*options)
  		return 0;
  	
  	while ((this_opt = strsep(&options, ",")) != NULL) {
  		if (!*this_opt) continue;
  		
  		if (! strcmp(this_opt, "inverse"))
  			inverse=1;
  		else if (! strcmp(this_opt, "redraw"))
  			ypan=0;
  		else if (! strcmp(this_opt, "ypan"))
  			ypan=1;
  		else if (! strcmp(this_opt, "ywrap"))
  			ypan=2;
  		else if (! strcmp(this_opt, "vgapal"))
  			pmi_setpal=0;
  		else if (! strcmp(this_opt, "pmipal"))
  			pmi_setpal=1;

  		else if (! strncmp(this_opt, "mtrr:", 5))
  			mtrr = simple_strtoul(this_opt+5, NULL, 0);

  		else if (! strcmp(this_opt, "nomtrr"))
  			mtrr=0;
  		else if (! strncmp(this_opt, "vtotal:", 7))
  			vram_total = simple_strtoul(this_opt+7, NULL, 0);
  		else if (! strncmp(this_opt, "vremap:", 7))
  			vram_remap = simple_strtoul(this_opt+7, NULL, 0);
  	}
  	return 0;
  }

  static int __init vesafb_probe(struct platform_device *dev)

  {

  	struct fb_info *info;
  	int i, err;
  	unsigned int size_vmode;
  	unsigned int size_remap;
  	unsigned int size_total;
  
  	if (screen_info.orig_video_isVGA != VIDEO_TYPE_VLFB)
  		return -ENODEV;

  	vga_compat = (screen_info.capabilities & 2) ? 0 : 1;

  	vesafb_fix.smem_start = screen_info.lfb_base;
  	vesafb_defined.bits_per_pixel = screen_info.lfb_depth;
  	if (15 == vesafb_defined.bits_per_pixel)
  		vesafb_defined.bits_per_pixel = 16;
  	vesafb_defined.xres = screen_info.lfb_width;
  	vesafb_defined.yres = screen_info.lfb_height;
  	vesafb_fix.line_length = screen_info.lfb_linelength;
  	vesafb_fix.visual   = (vesafb_defined.bits_per_pixel == 8) ?
  		FB_VISUAL_PSEUDOCOLOR : FB_VISUAL_TRUECOLOR;
  
  	/*   size_vmode -- that is the amount of memory needed for the
  	 *                 used video mode, i.e. the minimum amount of
  	 *                 memory we need. */
  	size_vmode = vesafb_defined.yres * vesafb_fix.line_length;
  
  	/*   size_total -- all video memory we have. Used for mtrr

  	 *                 entries, resource allocation and bounds

  	 *                 checking. */
  	size_total = screen_info.lfb_size * 65536;
  	if (vram_total)
  		size_total = vram_total * 1024 * 1024;
  	if (size_total < size_vmode)
  		size_total = size_vmode;
  
  	/*   size_remap -- the amount of video memory we are going to
  	 *                 use for vesafb.  With modern cards it is no
  	 *                 option to simply use size_total as that
  	 *                 wastes plenty of kernel address space. */
  	size_remap  = size_vmode * 2;
  	if (vram_remap)
  		size_remap = vram_remap * 1024 * 1024;
  	if (size_remap < size_vmode)
  		size_remap = size_vmode;
  	if (size_remap > size_total)
  		size_remap = size_total;
  	vesafb_fix.smem_len = size_remap;
  
  #ifndef __i386__
  	screen_info.vesapm_seg = 0;
  #endif
  
  	if (!request_mem_region(vesafb_fix.smem_start, size_total, "vesafb")) {
  		printk(KERN_WARNING

  		       "vesafb: cannot reserve video memory at 0x%lx
  ",

  			vesafb_fix.smem_start);
  		/* We cannot make this fatal. Sometimes this comes from magic
  		   spaces our resource handlers simply don't know about */
  	}
  
  	info = framebuffer_alloc(sizeof(u32) * 256, &dev->dev);
  	if (!info) {

  		release_mem_region(vesafb_fix.smem_start, size_total);

  		return -ENOMEM;
  	}
  	info->pseudo_palette = info->par;
  	info->par = NULL;

  	/* set vesafb aperture size for generic probing */

  	info->apertures = alloc_apertures(1);
  	if (!info->apertures) {
  		err = -ENOMEM;
  		goto err;
  	}
  	info->apertures->ranges[0].base = screen_info.lfb_base;
  	info->apertures->ranges[0].size = size_total;

  	printk(KERN_INFO "vesafb: mode is %dx%dx%d, linelength=%d, pages=%d
  ",
  	       vesafb_defined.xres, vesafb_defined.yres, vesafb_defined.bits_per_pixel, vesafb_fix.line_length, screen_info.pages);
  
  	if (screen_info.vesapm_seg) {
  		printk(KERN_INFO "vesafb: protected mode interface info at %04x:%04x
  ",
  		       screen_info.vesapm_seg,screen_info.vesapm_off);
  	}
  
  	if (screen_info.vesapm_seg < 0xc000)
  		ypan = pmi_setpal = 0; /* not available or some DOS TSR ... */
  
  	if (ypan || pmi_setpal) {

  		unsigned short *pmi_base;

  		pmi_base  = (unsigned short*)phys_to_virt(((unsigned long)screen_info.vesapm_seg << 4) + screen_info.vesapm_off);
  		pmi_start = (void*)((char*)pmi_base + pmi_base[1]);
  		pmi_pal   = (void*)((char*)pmi_base + pmi_base[2]);
  		printk(KERN_INFO "vesafb: pmi: set display start = %p, set palette = %p
  ",pmi_start,pmi_pal);
  		if (pmi_base[3]) {
  			printk(KERN_INFO "vesafb: pmi: ports = ");
  				for (i = pmi_base[3]/2; pmi_base[i] != 0xffff; i++)
  					printk("%x ",pmi_base[i]);
  			printk("
  ");
  			if (pmi_base[i] != 0xffff) {
  				/*
  				 * memory areas not supported (yet?)
  				 *
  				 * Rules are: we have to set up a descriptor for the requested
  				 * memory area and pass it in the ES register to the BIOS function.
  				 */
  				printk(KERN_INFO "vesafb: can't handle memory requests, pmi disabled
  ");
  				ypan = pmi_setpal = 0;
  			}
  		}
  	}

  	if (vesafb_defined.bits_per_pixel == 8 && !pmi_setpal && !vga_compat) {
  		printk(KERN_WARNING "vesafb: hardware palette is unchangeable,
  "
  		                    "        colors may be incorrect
  ");
  		vesafb_fix.visual = FB_VISUAL_STATIC_PSEUDOCOLOR;
  	}

  	vesafb_defined.xres_virtual = vesafb_defined.xres;
  	vesafb_defined.yres_virtual = vesafb_fix.smem_len / vesafb_fix.line_length;
  	if (ypan && vesafb_defined.yres_virtual > vesafb_defined.yres) {
  		printk(KERN_INFO "vesafb: scrolling: %s using protected mode interface, yres_virtual=%d
  ",
  		       (ypan > 1) ? "ywrap" : "ypan",vesafb_defined.yres_virtual);
  	} else {
  		printk(KERN_INFO "vesafb: scrolling: redraw
  ");
  		vesafb_defined.yres_virtual = vesafb_defined.yres;
  		ypan = 0;
  	}
  
  	/* some dummy values for timing to make fbset happy */
  	vesafb_defined.pixclock     = 10000000 / vesafb_defined.xres * 1000 / vesafb_defined.yres;
  	vesafb_defined.left_margin  = (vesafb_defined.xres / 8) & 0xf8;
  	vesafb_defined.hsync_len    = (vesafb_defined.xres / 8) & 0xf8;
  	
  	vesafb_defined.red.offset    = screen_info.red_pos;
  	vesafb_defined.red.length    = screen_info.red_size;
  	vesafb_defined.green.offset  = screen_info.green_pos;
  	vesafb_defined.green.length  = screen_info.green_size;
  	vesafb_defined.blue.offset   = screen_info.blue_pos;
  	vesafb_defined.blue.length   = screen_info.blue_size;
  	vesafb_defined.transp.offset = screen_info.rsvd_pos;
  	vesafb_defined.transp.length = screen_info.rsvd_size;
  
  	if (vesafb_defined.bits_per_pixel <= 8) {
  		depth = vesafb_defined.green.length;
  		vesafb_defined.red.length =
  		vesafb_defined.green.length =
  		vesafb_defined.blue.length =
  		vesafb_defined.bits_per_pixel;
  	}
  
  	printk(KERN_INFO "vesafb: %s: "
  	       "size=%d:%d:%d:%d, shift=%d:%d:%d:%d
  ",
  	       (vesafb_defined.bits_per_pixel > 8) ?

  	       "Truecolor" : (vga_compat || pmi_setpal) ?
  	       "Pseudocolor" : "Static Pseudocolor",

  	       screen_info.rsvd_size,
  	       screen_info.red_size,
  	       screen_info.green_size,
  	       screen_info.blue_size,
  	       screen_info.rsvd_pos,
  	       screen_info.red_pos,
  	       screen_info.green_pos,
  	       screen_info.blue_pos);
  
  	vesafb_fix.ypanstep  = ypan     ? 1 : 0;
  	vesafb_fix.ywrapstep = (ypan>1) ? 1 : 0;
  
  	/* request failure does not faze us, as vgacon probably has this
  	 * region already (FIXME) */
  	request_region(0x3c0, 32, "vesafb");

  #ifdef CONFIG_MTRR

  	if (mtrr) {

  		unsigned int temp_size = size_total;

  		unsigned int type = 0;
  
  		switch (mtrr) {
  		case 1:
  			type = MTRR_TYPE_UNCACHABLE;
  			break;
  		case 2:
  			type = MTRR_TYPE_WRBACK;
  			break;
  		case 3:
  			type = MTRR_TYPE_WRCOMB;
  			break;
  		case 4:
  			type = MTRR_TYPE_WRTHROUGH;
  			break;
  		default:
  			type = 0;
  			break;
  		}
  
  		if (type) {
  			int rc;
  
  			/* Find the largest power-of-two */

  			temp_size = roundup_pow_of_two(temp_size);

  
  			/* Try and find a power of two to add */
  			do {
  				rc = mtrr_add(vesafb_fix.smem_start, temp_size,
  					      type, 1);
  				temp_size >>= 1;
  			} while (temp_size >= PAGE_SIZE && rc == -EINVAL);

  		}
  	}

  #endif

  	switch (mtrr) {
  	case 1: /* uncachable */
  		info->screen_base = ioremap_nocache(vesafb_fix.smem_start, vesafb_fix.smem_len);
  		break;
  	case 2: /* write-back */
  		info->screen_base = ioremap_cache(vesafb_fix.smem_start, vesafb_fix.smem_len);
  		break;
  	case 3: /* write-combining */
  		info->screen_base = ioremap_wc(vesafb_fix.smem_start, vesafb_fix.smem_len);
  		break;
  	case 4: /* write-through */
  	default:
  		info->screen_base = ioremap(vesafb_fix.smem_start, vesafb_fix.smem_len);
  		break;
  	}
  	if (!info->screen_base) {
  		printk(KERN_ERR
  		       "vesafb: abort, cannot ioremap video memory 0x%x @ 0x%lx
  ",
  			vesafb_fix.smem_len, vesafb_fix.smem_start);
  		err = -EIO;
  		goto err;
  	}
  
  	printk(KERN_INFO "vesafb: framebuffer at 0x%lx, mapped to 0x%p, "
  	       "using %dk, total %dk
  ",
  	       vesafb_fix.smem_start, info->screen_base,
  	       size_remap/1024, size_total/1024);

  	info->fbops = &vesafb_ops;
  	info->var = vesafb_defined;
  	info->fix = vesafb_fix;

  	info->flags = FBINFO_FLAG_DEFAULT | FBINFO_MISC_FIRMWARE |

  		(ypan ? FBINFO_HWACCEL_YPAN : 0);

  	if (!ypan)
  		info->fbops->fb_pan_display = NULL;

  	if (fb_alloc_cmap(&info->cmap, 256, 0) < 0) {
  		err = -ENOMEM;
  		goto err;
  	}
  	if (register_framebuffer(info)<0) {
  		err = -EINVAL;
  		fb_dealloc_cmap(&info->cmap);
  		goto err;
  	}
  	printk(KERN_INFO "fb%d: %s frame buffer device
  ",
  	       info->node, info->fix.id);
  	return 0;
  err:

  	if (info->screen_base)
  		iounmap(info->screen_base);

  	framebuffer_release(info);
  	release_mem_region(vesafb_fix.smem_start, size_total);
  	return err;
  }

  static struct platform_driver vesafb_driver = {

  	.driver	= {
  		.name	= "vesafb",
  	},

  };

  static struct platform_device *vesafb_device;

  
  static int __init vesafb_init(void)
  {
  	int ret;
  	char *option = NULL;
  
  	/* ignore error return of fb_get_options */
  	fb_get_options("vesafb", &option);
  	vesafb_setup(option);

  	vesafb_device = platform_device_alloc("vesafb", 0);
  	if (!vesafb_device)
  		return -ENOMEM;

  	ret = platform_device_add(vesafb_device);
  	if (!ret) {
  		ret = platform_driver_probe(&vesafb_driver, vesafb_probe);
  		if (ret)
  			platform_device_del(vesafb_device);
  	}

  	if (ret) {
  		platform_device_put(vesafb_device);
  		vesafb_device = NULL;

  	}

  	return ret;
  }
  module_init(vesafb_init);
  
  MODULE_LICENSE("GPL");