/**
 * Copyright (c) 2012 Anup Patel.
 * All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * @file vmm_modedb.c
 * @author Anup Patel (anup@brainfault.org)
 * @brief Standard video mode database management
 *
 * The source has been largely adapted from Linux 3.x or higher:
 * drivers/video/modedb.c
 *
 *	Copyright (C) 1999 Geert Uytterhoeven
 *
 *	2001 - Documented with DocBook
 *	- Brad Douglas <brad@neruo.com>
 *
 * The original code is licensed under the GPL.
 */

#include <vmm_error.h>
#include <vmm_stdio.h>
#include <vmm_heap.h>
#include <vmm_modules.h>
#include <fb/vmm_fb.h>
#include <libs/stringlib.h>

#undef DEBUG

#define name_matches(v, s, l) \
    ((v).name && !strncmp((s), (v).name, (l)) && strlen((v).name) == (l))
#define res_matches(v, x, y) \
    ((v).xres == (x) && (v).yres == (y))

#ifdef DEBUG
#define DPRINTK(fmt, args...)	vmm_printf("modedb %s: " fmt, __func__ , ## args)
#else
#define DPRINTK(fmt, args...)
#endif

const char *fb_mode_option;

/*
 *  Standard video mode definitions (taken from XFree86)
 */

static const struct vmm_fb_videomode modedb[] = {

	/* 640x400 @ 70 Hz, 31.5 kHz hsync */
	{ NULL, 70, 640, 400, 39721, 40, 24, 39, 9, 96, 2, 0,
		FB_VMODE_NONINTERLACED },

	/* 640x480 @ 60 Hz, 31.5 kHz hsync */
	{ NULL, 60, 640, 480, 39721, 40, 24, 32, 11, 96, 2,	0,
		FB_VMODE_NONINTERLACED },

	/* 800x600 @ 56 Hz, 35.15 kHz hsync */
	{ NULL, 56, 800, 600, 27777, 128, 24, 22, 1, 72, 2,	0,
		FB_VMODE_NONINTERLACED },

	/* 1024x768 @ 87 Hz interlaced, 35.5 kHz hsync */
	{ NULL, 87, 1024, 768, 22271, 56, 24, 33, 8, 160, 8, 0,
		FB_VMODE_INTERLACED },

	/* 640x400 @ 85 Hz, 37.86 kHz hsync */
	{ NULL, 85, 640, 400, 31746, 96, 32, 41, 1, 64, 3,
		FB_SYNC_VERT_HIGH_ACT, FB_VMODE_NONINTERLACED },

	/* 640x480 @ 72 Hz, 36.5 kHz hsync */
	{ NULL, 72, 640, 480, 31746, 144, 40, 30, 8, 40, 3, 0,
		FB_VMODE_NONINTERLACED },

	/* 640x480 @ 75 Hz, 37.50 kHz hsync */
	{ NULL, 75, 640, 480, 31746, 120, 16, 16, 1, 64, 3,	0,
		FB_VMODE_NONINTERLACED },

	/* 800x600 @ 60 Hz, 37.8 kHz hsync */
	{ NULL, 60, 800, 600, 25000, 88, 40, 23, 1, 128, 4,
		FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
		FB_VMODE_NONINTERLACED },

	/* 640x480 @ 85 Hz, 43.27 kHz hsync */
	{ NULL, 85, 640, 480, 27777, 80, 56, 25, 1, 56, 3, 0,
		FB_VMODE_NONINTERLACED },

	/* 1152x864 @ 89 Hz interlaced, 44 kHz hsync */
	{ NULL, 89, 1152, 864, 15384, 96, 16, 110, 1, 216, 10, 0,
		FB_VMODE_INTERLACED },
	/* 800x600 @ 72 Hz, 48.0 kHz hsync */
	{ NULL, 72, 800, 600, 20000, 64, 56, 23, 37, 120, 6,
		FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
		FB_VMODE_NONINTERLACED },

	/* 1024x768 @ 60 Hz, 48.4 kHz hsync */
	{ NULL, 60, 1024, 768, 15384, 168, 8, 29, 3, 144, 6, 0,
		FB_VMODE_NONINTERLACED },

	/* 640x480 @ 100 Hz, 53.01 kHz hsync */
	{ NULL, 100, 640, 480, 21834, 96, 32, 36, 8, 96, 6,	0,
		FB_VMODE_NONINTERLACED },

	/* 1152x864 @ 60 Hz, 53.5 kHz hsync */
	{ NULL, 60, 1152, 864, 11123, 208, 64, 16, 4, 256, 8, 0,
		FB_VMODE_NONINTERLACED },

	/* 800x600 @ 85 Hz, 55.84 kHz hsync */
	{ NULL, 85, 800, 600, 16460, 160, 64, 36, 16, 64, 5, 0,
		FB_VMODE_NONINTERLACED },

	/* 1024x768 @ 70 Hz, 56.5 kHz hsync */
	{ NULL, 70, 1024, 768, 13333, 144, 24, 29, 3, 136, 6, 0,
		FB_VMODE_NONINTERLACED },

	/* 1280x1024 @ 87 Hz interlaced, 51 kHz hsync */
	{ NULL, 87, 1280, 1024, 12500, 56, 16, 128, 1, 216, 12,	0,
		FB_VMODE_INTERLACED },

	/* 800x600 @ 100 Hz, 64.02 kHz hsync */
	{ NULL, 100, 800, 600, 14357, 160, 64, 30, 4, 64, 6, 0,
		FB_VMODE_NONINTERLACED },

	/* 1024x768 @ 76 Hz, 62.5 kHz hsync */
	{ NULL, 76, 1024, 768, 11764, 208, 8, 36, 16, 120, 3, 0,
		FB_VMODE_NONINTERLACED },

	/* 1152x864 @ 70 Hz, 62.4 kHz hsync */
	{ NULL, 70, 1152, 864, 10869, 106, 56, 20, 1, 160, 10, 0,
		FB_VMODE_NONINTERLACED },

	/* 1280x1024 @ 61 Hz, 64.2 kHz hsync */
	{ NULL, 61, 1280, 1024, 9090, 200, 48, 26, 1, 184, 3, 0,
		FB_VMODE_NONINTERLACED },

	/* 1400x1050 @ 60Hz, 63.9 kHz hsync */
	{ NULL, 60, 1400, 1050, 9259, 136, 40, 13, 1, 112, 3, 0,
		FB_VMODE_NONINTERLACED },

	/* 1400x1050 @ 75,107 Hz, 82,392 kHz +hsync +vsync*/
	{ NULL, 75, 1400, 1050, 7190, 120, 56, 23, 10, 112, 13,
		FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
		FB_VMODE_NONINTERLACED },

	/* 1400x1050 @ 60 Hz, ? kHz +hsync +vsync*/
	{ NULL, 60, 1400, 1050, 9259, 128, 40, 12, 0, 112, 3,
		FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
		FB_VMODE_NONINTERLACED },

	/* 1024x768 @ 85 Hz, 70.24 kHz hsync */
	{ NULL, 85, 1024, 768, 10111, 192, 32, 34, 14, 160, 6, 0,
		FB_VMODE_NONINTERLACED },

	/* 1152x864 @ 78 Hz, 70.8 kHz hsync */
	{ NULL, 78, 1152, 864, 9090, 228, 88, 32, 0, 84, 12, 0,
		FB_VMODE_NONINTERLACED },

	/* 1280x1024 @ 70 Hz, 74.59 kHz hsync */
	{ NULL, 70, 1280, 1024, 7905, 224, 32, 28, 8, 160, 8, 0,
		FB_VMODE_NONINTERLACED },

	/* 1600x1200 @ 60Hz, 75.00 kHz hsync */
	{ NULL, 60, 1600, 1200, 6172, 304, 64, 46, 1, 192, 3,
		FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
		FB_VMODE_NONINTERLACED },

	/* 1152x864 @ 84 Hz, 76.0 kHz hsync */
	{ NULL, 84, 1152, 864, 7407, 184, 312, 32, 0, 128, 12, 0,
		FB_VMODE_NONINTERLACED },

	/* 1280x1024 @ 74 Hz, 78.85 kHz hsync */
	{ NULL, 74, 1280, 1024, 7407, 256, 32, 34, 3, 144, 3, 0,
		FB_VMODE_NONINTERLACED },

	/* 1024x768 @ 100Hz, 80.21 kHz hsync */
	{ NULL, 100, 1024, 768, 8658, 192, 32, 21, 3, 192, 10, 0,
		FB_VMODE_NONINTERLACED },

	/* 1280x1024 @ 76 Hz, 81.13 kHz hsync */
	{ NULL, 76, 1280, 1024, 7407, 248, 32, 34, 3, 104, 3, 0,
		FB_VMODE_NONINTERLACED },

	/* 1600x1200 @ 70 Hz, 87.50 kHz hsync */
	{ NULL, 70, 1600, 1200, 5291, 304, 64, 46, 1, 192, 3, 0,
		FB_VMODE_NONINTERLACED },

	/* 1152x864 @ 100 Hz, 89.62 kHz hsync */
	{ NULL, 100, 1152, 864, 7264, 224, 32, 17, 2, 128, 19, 0,
		FB_VMODE_NONINTERLACED },

	/* 1280x1024 @ 85 Hz, 91.15 kHz hsync */
	{ NULL, 85, 1280, 1024, 6349, 224, 64, 44, 1, 160, 3,
		FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
		FB_VMODE_NONINTERLACED },

	/* 1600x1200 @ 75 Hz, 93.75 kHz hsync */
	{ NULL, 75, 1600, 1200, 4938, 304, 64, 46, 1, 192, 3,
		FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
		FB_VMODE_NONINTERLACED },

	/* 1680x1050 @ 60 Hz, 65.191 kHz hsync */
	{ NULL, 60, 1680, 1050, 6848, 280, 104, 30, 3, 176, 6,
		FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
		FB_VMODE_NONINTERLACED },

	/* 1600x1200 @ 85 Hz, 105.77 kHz hsync */
	{ NULL, 85, 1600, 1200, 4545, 272, 16, 37, 4, 192, 3,
		FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
		FB_VMODE_NONINTERLACED },

	/* 1280x1024 @ 100 Hz, 107.16 kHz hsync */
	{ NULL, 100, 1280, 1024, 5502, 256, 32, 26, 7, 128, 15, 0,
		FB_VMODE_NONINTERLACED },

	/* 1800x1440 @ 64Hz, 96.15 kHz hsync  */
	{ NULL, 64, 1800, 1440, 4347, 304, 96, 46, 1, 192, 3,
		FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
		FB_VMODE_NONINTERLACED },

	/* 1800x1440 @ 70Hz, 104.52 kHz hsync  */
	{ NULL, 70, 1800, 1440, 4000, 304, 96, 46, 1, 192, 3,
		FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
		FB_VMODE_NONINTERLACED },

	/* 512x384 @ 78 Hz, 31.50 kHz hsync */
	{ NULL, 78, 512, 384, 49603, 48, 16, 16, 1, 64, 3, 0,
		FB_VMODE_NONINTERLACED },

	/* 512x384 @ 85 Hz, 34.38 kHz hsync */
	{ NULL, 85, 512, 384, 45454, 48, 16, 16, 1, 64, 3, 0,
		FB_VMODE_NONINTERLACED },

	/* 320x200 @ 70 Hz, 31.5 kHz hsync, 8:5 aspect ratio */
	{ NULL, 70, 320, 200, 79440, 16, 16, 20, 4, 48, 1, 0,
		FB_VMODE_DOUBLE },

	/* 320x240 @ 60 Hz, 31.5 kHz hsync, 4:3 aspect ratio */
	{ NULL, 60, 320, 240, 79440, 16, 16, 16, 5, 48, 1, 0,
		FB_VMODE_DOUBLE },

	/* 320x240 @ 72 Hz, 36.5 kHz hsync */
	{ NULL, 72, 320, 240, 63492, 16, 16, 16, 4, 48, 2, 0,
		FB_VMODE_DOUBLE },

	/* 400x300 @ 56 Hz, 35.2 kHz hsync, 4:3 aspect ratio */
	{ NULL, 56, 400, 300, 55555, 64, 16, 10, 1, 32, 1, 0,
		FB_VMODE_DOUBLE },

	/* 400x300 @ 60 Hz, 37.8 kHz hsync */
	{ NULL, 60, 400, 300, 50000, 48, 16, 11, 1, 64, 2, 0,
		FB_VMODE_DOUBLE },

	/* 400x300 @ 72 Hz, 48.0 kHz hsync */
	{ NULL, 72, 400, 300, 40000, 32, 24, 11, 19, 64, 3,	0,
		FB_VMODE_DOUBLE },

	/* 480x300 @ 56 Hz, 35.2 kHz hsync, 8:5 aspect ratio */
	{ NULL, 56, 480, 300, 46176, 80, 16, 10, 1, 40, 1, 0,
		FB_VMODE_DOUBLE },

	/* 480x300 @ 60 Hz, 37.8 kHz hsync */
	{ NULL, 60, 480, 300, 41858, 56, 16, 11, 1, 80, 2, 0,
		FB_VMODE_DOUBLE },

	/* 480x300 @ 63 Hz, 39.6 kHz hsync */
	{ NULL, 63, 480, 300, 40000, 56, 16, 11, 1, 80, 2, 0,
		FB_VMODE_DOUBLE },

	/* 480x300 @ 72 Hz, 48.0 kHz hsync */
	{ NULL, 72, 480, 300, 33386, 40, 24, 11, 19, 80, 3, 0,
		FB_VMODE_DOUBLE },

	/* 1920x1200 @ 60 Hz, 74.5 Khz hsync */
	{ NULL, 60, 1920, 1200, 5177, 128, 336, 1, 38, 208, 3,
		FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
		FB_VMODE_NONINTERLACED },

	/* 1152x768, 60 Hz, PowerBook G4 Titanium I and II */
	{ NULL, 60, 1152, 768, 14047, 158, 26, 29, 3, 136, 6,
		FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
		FB_VMODE_NONINTERLACED },

	/* 1366x768, 60 Hz, 47.403 kHz hsync, WXGA 16:9 aspect ratio */
	{ NULL, 60, 1366, 768, 13806, 120, 10, 14, 3, 32, 5, 0,
		FB_VMODE_NONINTERLACED },

	/* 1280x800, 60 Hz, 47.403 kHz hsync, WXGA 16:10 aspect ratio */
	{ NULL, 60, 1280, 800, 12048, 200, 64, 24, 1, 136, 3, 0,
		FB_VMODE_NONINTERLACED },

	/* 720x576i @ 50 Hz, 15.625 kHz hsync (PAL RGB) */
	{ NULL, 50, 720, 576, 74074, 64, 16, 39, 5, 64, 5, 0,
		FB_VMODE_INTERLACED },

	/* 800x520i @ 50 Hz, 15.625 kHz hsync (PAL RGB) */
	{ NULL, 50, 800, 520, 58823, 144, 64, 72, 28, 80, 5, 0,
		FB_VMODE_INTERLACED },

	/* 864x480 @ 60 Hz, 35.15 kHz hsync */
	{ NULL, 60, 864, 480, 27777, 1, 1, 1, 1, 0, 0,
		0, FB_VMODE_NONINTERLACED },
};

#ifdef CONFIG_FB_MODE_HELPERS
const struct vmm_fb_videomode cea_modes[64] = {
	/* #1: 640x480p@59.94/60Hz */
	[1] = {
		NULL, 60, 640, 480, 39722, 48, 16, 33, 10, 96, 2, 0,
		FB_VMODE_NONINTERLACED, 0,
	},
	/* #3: 720x480p@59.94/60Hz */
	[3] = {
		NULL, 60, 720, 480, 37037, 60, 16, 30, 9, 62, 6, 0,
		FB_VMODE_NONINTERLACED, 0,
	},
	/* #5: 1920x1080i@59.94/60Hz */
	[5] = {
		NULL, 60, 1920, 1080, 13763, 148, 88, 15, 2, 44, 5,
		FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
		FB_VMODE_INTERLACED, 0,
	},
	/* #7: 720(1440)x480iH@59.94/60Hz */
	[7] = {
		NULL, 60, 1440, 480, 18554/*37108*/, 114, 38, 15, 4, 124, 3, 0,
		FB_VMODE_INTERLACED, 0,
	},
	/* #9: 720(1440)x240pH@59.94/60Hz */
	[9] = {
		NULL, 60, 1440, 240, 18554, 114, 38, 16, 4, 124, 3, 0,
		FB_VMODE_NONINTERLACED, 0,
	},
	/* #18: 720x576pH@50Hz */
	[18] = {
		NULL, 50, 720, 576, 37037, 68, 12, 39, 5, 64, 5, 0,
		FB_VMODE_NONINTERLACED, 0,
	},
	/* #19: 1280x720p@50Hz */
	[19] = {
		NULL, 50, 1280, 720, 13468, 220, 440, 20, 5, 40, 5,
		FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
		FB_VMODE_NONINTERLACED, 0,
	},
	/* #20: 1920x1080i@50Hz */
	[20] = {
		NULL, 50, 1920, 1080, 13480, 148, 528, 15, 5, 528, 5,
		FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
		FB_VMODE_INTERLACED, 0,
	},
	/* #32: 1920x1080p@23.98/24Hz */
	[32] = {
		NULL, 24, 1920, 1080, 13468, 148, 638, 36, 4, 44, 5,
		FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
		FB_VMODE_NONINTERLACED, 0,
	},
	/* #35: (2880)x480p4x@59.94/60Hz */
	[35] = {
		NULL, 60, 2880, 480, 9250, 240, 64, 30, 9, 248, 6, 0,
		FB_VMODE_NONINTERLACED, 0,
	},
};

const struct vmm_fb_videomode vesa_modes[] = {
	/* 0 640x350-85 VESA */
	{ NULL, 85, 640, 350, 31746,  96, 32, 60, 32, 64, 3,
	  FB_SYNC_HOR_HIGH_ACT, FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA},
	/* 1 640x400-85 VESA */
	{ NULL, 85, 640, 400, 31746,  96, 32, 41, 01, 64, 3,
	  FB_SYNC_VERT_HIGH_ACT, FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 2 720x400-85 VESA */
	{ NULL, 85, 721, 400, 28169, 108, 36, 42, 01, 72, 3,
	  FB_SYNC_VERT_HIGH_ACT, FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 3 640x480-60 VESA */
	{ NULL, 60, 640, 480, 39682,  48, 16, 33, 10, 96, 2,
	  0, FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 4 640x480-72 VESA */
	{ NULL, 72, 640, 480, 31746, 128, 24, 29, 9, 40, 2,
	  0, FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 5 640x480-75 VESA */
	{ NULL, 75, 640, 480, 31746, 120, 16, 16, 01, 64, 3,
	  0, FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 6 640x480-85 VESA */
	{ NULL, 85, 640, 480, 27777, 80, 56, 25, 01, 56, 3,
	  0, FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 7 800x600-56 VESA */
	{ NULL, 56, 800, 600, 27777, 128, 24, 22, 01, 72, 2,
	  FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
	  FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 8 800x600-60 VESA */
	{ NULL, 60, 800, 600, 25000, 88, 40, 23, 01, 128, 4,
	  FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
	  FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 9 800x600-72 VESA */
	{ NULL, 72, 800, 600, 20000, 64, 56, 23, 37, 120, 6,
	  FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
	  FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 10 800x600-75 VESA */
	{ NULL, 75, 800, 600, 20202, 160, 16, 21, 01, 80, 3,
	  FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
	  FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 11 800x600-85 VESA */
	{ NULL, 85, 800, 600, 17761, 152, 32, 27, 01, 64, 3,
	  FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
	  FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
        /* 12 1024x768i-43 VESA */
	{ NULL, 43, 1024, 768, 22271, 56, 8, 41, 0, 176, 8,
	  FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
	  FB_VMODE_INTERLACED, FB_MODE_IS_VESA },
	/* 13 1024x768-60 VESA */
	{ NULL, 60, 1024, 768, 15384, 160, 24, 29, 3, 136, 6,
	  0, FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 14 1024x768-70 VESA */
	{ NULL, 70, 1024, 768, 13333, 144, 24, 29, 3, 136, 6,
	  0, FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 15 1024x768-75 VESA */
	{ NULL, 75, 1024, 768, 12690, 176, 16, 28, 1, 96, 3,
	  FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
	  FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 16 1024x768-85 VESA */
	{ NULL, 85, 1024, 768, 10582, 208, 48, 36, 1, 96, 3,
	  FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
	  FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 17 1152x864-75 VESA */
	{ NULL, 75, 1152, 864, 9259, 256, 64, 32, 1, 128, 3,
	  FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
	  FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 18 1280x960-60 VESA */
	{ NULL, 60, 1280, 960, 9259, 312, 96, 36, 1, 112, 3,
	  FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
	  FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 19 1280x960-85 VESA */
	{ NULL, 85, 1280, 960, 6734, 224, 64, 47, 1, 160, 3,
	  FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
	  FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 20 1280x1024-60 VESA */
	{ NULL, 60, 1280, 1024, 9259, 248, 48, 38, 1, 112, 3,
	  FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
	  FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 21 1280x1024-75 VESA */
	{ NULL, 75, 1280, 1024, 7407, 248, 16, 38, 1, 144, 3,
	  FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
	  FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 22 1280x1024-85 VESA */
	{ NULL, 85, 1280, 1024, 6349, 224, 64, 44, 1, 160, 3,
	  FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
	  FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 23 1600x1200-60 VESA */
	{ NULL, 60, 1600, 1200, 6172, 304, 64, 46, 1, 192, 3,
	  FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
	  FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 24 1600x1200-65 VESA */
	{ NULL, 65, 1600, 1200, 5698, 304,  64, 46, 1, 192, 3,
	  FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
	  FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 25 1600x1200-70 VESA */
	{ NULL, 70, 1600, 1200, 5291, 304, 64, 46, 1, 192, 3,
	  FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
	  FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 26 1600x1200-75 VESA */
	{ NULL, 75, 1600, 1200, 4938, 304, 64, 46, 1, 192, 3,
	  FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
	  FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 27 1600x1200-85 VESA */
	{ NULL, 85, 1600, 1200, 4357, 304, 64, 46, 1, 192, 3,
	  FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
	  FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 28 1792x1344-60 VESA */
	{ NULL, 60, 1792, 1344, 4882, 328, 128, 46, 1, 200, 3,
	  FB_SYNC_VERT_HIGH_ACT, FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 29 1792x1344-75 VESA */
	{ NULL, 75, 1792, 1344, 3831, 352, 96, 69, 1, 216, 3,
	  FB_SYNC_VERT_HIGH_ACT, FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 30 1856x1392-60 VESA */
	{ NULL, 60, 1856, 1392, 4580, 352, 96, 43, 1, 224, 3,
	  FB_SYNC_VERT_HIGH_ACT, FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 31 1856x1392-75 VESA */
	{ NULL, 75, 1856, 1392, 3472, 352, 128, 104, 1, 224, 3,
	  FB_SYNC_VERT_HIGH_ACT, FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 32 1920x1440-60 VESA */
	{ NULL, 60, 1920, 1440, 4273, 344, 128, 56, 1, 200, 3,
	  FB_SYNC_VERT_HIGH_ACT, FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
	/* 33 1920x1440-75 VESA */
	{ NULL, 75, 1920, 1440, 3367, 352, 144, 56, 1, 224, 3,
	  FB_SYNC_VERT_HIGH_ACT, FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },
};
#endif /* CONFIG_FB_MODE_HELPERS */

/**
 *	vmm_fb_try_mode - test a video mode
 *	@var: frame buffer user defined part of display
 *	@info: frame buffer info structure
 *	@mode: frame buffer video mode structure
 *	@bpp: color depth in bits per pixel
 *
 *	Tries a video mode to test it's validity for device @info.
 *
 *	Returns 1 on success.
 *
 */

static int vmm_fb_try_mode(struct vmm_fb_var_screeninfo *var, struct vmm_fb_info *info,
		       const struct vmm_fb_videomode *mode, unsigned int bpp)
{
    int err = 0;

    DPRINTK("Trying mode %s %dx%d-%d@%d\n", mode->name ? mode->name : "noname",
	    mode->xres, mode->yres, bpp, mode->refresh);
    var->xres = mode->xres;
    var->yres = mode->yres;
    var->xres_virtual = mode->xres;
    var->yres_virtual = mode->yres;
    var->xoffset = 0;
    var->yoffset = 0;
    var->bits_per_pixel = bpp;
    var->activate |= FB_ACTIVATE_TEST;
    var->pixclock = mode->pixclock;
    var->left_margin = mode->left_margin;
    var->right_margin = mode->right_margin;
    var->upper_margin = mode->upper_margin;
    var->lower_margin = mode->lower_margin;
    var->hsync_len = mode->hsync_len;
    var->vsync_len = mode->vsync_len;
    var->sync = mode->sync;
    var->vmode = mode->vmode;
    if (info->fbops->fb_check_var)
    	err = info->fbops->fb_check_var(var, info);
    var->activate &= ~FB_ACTIVATE_TEST;
    return err;
}

/**
 *	vmm_fb_find_mode - finds a valid video mode
 *	@var: frame buffer user defined part of display
 *	@info: frame buffer info structure
 *	@mode_option: string video mode to find
 *	@db: video mode database
 *	@dbsize: size of @db
 *	@default_mode: default video mode to fall back to
 *	@default_bpp: default color depth in bits per pixel
 *
 *	Finds a suitable video mode, starting with the specified mode
 *	in @mode_option with fallback to @default_mode.  If
 *	@default_mode fails, all modes in the video mode database will
 *	be tried.
 *
 *	Valid mode specifiers for @mode_option:
 *
 *	<xres>x<yres>[M][R][-<bpp>][@<refresh>][i][m] or
 *	<name>[-<bpp>][@<refresh>]
 *
 *	with <xres>, <yres>, <bpp> and <refresh> decimal numbers and
 *	<name> a string.
 *
 *      If 'M' is present after yres (and before refresh/bpp if present),
 *      the function will compute the timings using VESA(tm) Coordinated
 *      Video Timings (CVT).  If 'R' is present after 'M', will compute with
 *      reduced blanking (for flatpanels).  If 'i' is present, compute
 *      interlaced mode.  If 'm' is present, add margins equal to 1.8%
 *      of xres rounded down to 8 pixels, and 1.8% of yres. The char
 *      'i' and 'm' must be after 'M' and 'R'. Example:
 *
 *      1024x768MR-8@60m - Reduced blank with margins at 60Hz.
 *
 *	NOTE: The passed struct @var is _not_ cleared!  This allows you
 *	to supply values for e.g. the grayscale and accel_flags fields.
 *
 *	Returns zero for failure, 1 if using specified @mode_option,
 *	2 if using specified @mode_option with an ignored refresh rate,
 *	3 if default mode is used, 4 if fall back to any valid mode.
 *
 */

int vmm_fb_find_mode(struct vmm_fb_var_screeninfo *var,
		     struct vmm_fb_info *info, const char *mode_option,
		     const struct vmm_fb_videomode *db, unsigned int dbsize,
		     const struct vmm_fb_videomode *default_mode,
		     unsigned int default_bpp)
{
    int i;

    /* Set up defaults */
    if (!db) {
	db = modedb;
	dbsize = array_size(modedb);
    }

    if (!default_mode)
	default_mode = &db[0];

    if (!default_bpp)
	default_bpp = 8;

    /* Did the user specify a video mode? */
    if (!mode_option)
	mode_option = fb_mode_option;
    if (mode_option) {
	const char *name = mode_option;
	unsigned int namelen = strlen(name);
	int res_specified = 0, bpp_specified = 0, refresh_specified = 0;
	unsigned int xres = 0, yres = 0, bpp = default_bpp, refresh = 0;
	int yres_specified = 0, cvt = 0, rb = 0, interlace = 0, margins = 0;
	u32 best, diff, tdiff;

	for (i = namelen-1; i >= 0; i--) {
	    switch (name[i]) {
		case '@':
		    namelen = i;
		    if (!refresh_specified && !bpp_specified &&
			!yres_specified) {
			refresh = strtoul(&name[i+1], NULL, 0);
			refresh_specified = 1;
			if (cvt || rb)
			    cvt = 0;
		    } else
			goto done;
		    break;
		case '-':
		    namelen = i;
		    if (!bpp_specified && !yres_specified) {
			bpp = strtoul(&name[i+1], NULL, 0);
			bpp_specified = 1;
			if (cvt || rb)
			    cvt = 0;
		    } else
			goto done;
		    break;
		case 'x':
		    if (!yres_specified) {
			yres = strtoul(&name[i+1], NULL, 0);
			yres_specified = 1;
		    } else
			goto done;
		    break;
		case '0' ... '9':
		    break;
		case 'M':
		    if (!yres_specified)
			cvt = 1;
		    break;
		case 'R':
		    if (!cvt)
			rb = 1;
		    break;
		case 'm':
		    if (!cvt)
			margins = 1;
		    break;
		case 'i':
		    if (!cvt)
			interlace = 1;
		    break;
		default:
		    goto done;
	    }
	}
	if (i < 0 && yres_specified) {
	    xres = strtoul(name, NULL, 0);
	    res_specified = 1;
	}
done:
	if (cvt) {
	    struct vmm_fb_videomode cvt_mode;
	    int ret;

	    DPRINTK("CVT mode %dx%d@%dHz%s%s%s\n", xres, yres,
		    (refresh) ? refresh : 60, (rb) ? " reduced blanking" :
		    "", (margins) ? " with margins" : "", (interlace) ?
		    " interlaced" : "");

	    memset(&cvt_mode, 0, sizeof(cvt_mode));
	    cvt_mode.xres = xres;
	    cvt_mode.yres = yres;
	    cvt_mode.refresh = (refresh) ? refresh : 60;

	    if (interlace)
		cvt_mode.vmode |= FB_VMODE_INTERLACED;
	    else
		cvt_mode.vmode &= ~FB_VMODE_INTERLACED;

	    ret = vmm_fb_find_mode_cvt(&cvt_mode, margins, rb);

	    if (!ret && !vmm_fb_try_mode(var, info, &cvt_mode, bpp)) {
		DPRINTK("modedb CVT: CVT mode ok\n");
		return 1;
	    }

	    DPRINTK("CVT mode invalid, getting mode from database\n");
	}

	DPRINTK("Trying specified video mode%s %ix%i\n",
	    refresh_specified ? "" : " (ignoring refresh rate)", xres, yres);

	if (!refresh_specified) {
		/*
		 * If the caller has provided a custom mode database and a
		 * valid monspecs structure, we look for the mode with the
		 * highest refresh rate.  Otherwise we play it safe it and
		 * try to find a mode with a refresh rate closest to the
		 * standard 60 Hz.
		 */
		if (db != modedb &&
		    info->monspecs.vfmin && info->monspecs.vfmax &&
		    info->monspecs.hfmin && info->monspecs.hfmax &&
		    info->monspecs.dclkmax) {
			refresh = 1000;
		} else {
			refresh = 60;
		}
	}

	diff = -1;
	best = -1;
	for (i = 0; i < dbsize; i++) {
		if ((name_matches(db[i], name, namelen) ||
		    (res_specified && res_matches(db[i], xres, yres))) &&
		    !vmm_fb_try_mode(var, info, &db[i], bpp)) {
			if (refresh_specified && db[i].refresh == refresh) {
				return 1;
			} else {
				if (abs(db[i].refresh - refresh) < diff) {
					diff = abs(db[i].refresh - refresh);
					best = i;
				}
			}
		}
	}
	if (best != -1) {
		vmm_fb_try_mode(var, info, &db[best], bpp);
		return (refresh_specified) ? 2 : 1;
	}

	diff = 2 * (xres + yres);
	best = -1;
	DPRINTK("Trying best-fit modes\n");
	for (i = 0; i < dbsize; i++) {
		DPRINTK("Trying %ix%i\n", db[i].xres, db[i].yres);
		if (!vmm_fb_try_mode(var, info, &db[i], bpp)) {
			tdiff = abs(db[i].xres - xres) +
				abs(db[i].yres - yres);

			/*
			 * Penalize modes with resolutions smaller
			 * than requested.
			 */
			if (xres > db[i].xres || yres > db[i].yres)
				tdiff += xres + yres;

			if (diff > tdiff) {
				diff = tdiff;
				best = i;
			}
		}
	}
	if (best != -1) {
	    vmm_fb_try_mode(var, info, &db[best], bpp);
	    return 5;
	}
    }

    DPRINTK("Trying default video mode\n");
    if (!vmm_fb_try_mode(var, info, default_mode, default_bpp))
	return 3;

    DPRINTK("Trying all modes\n");
    for (i = 0; i < dbsize; i++)
	if (!vmm_fb_try_mode(var, info, &db[i], default_bpp))
	    return 4;

    DPRINTK("No valid mode found\n");
    return 0;
}
VMM_EXPORT_SYMBOL(vmm_fb_find_mode);

/**
 * Convert vmm_fb_var_screeninfo to vmm_fb_videomode
 * @mode: pointer to struct fb_videomode
 * @var: pointer to struct fb_var_screeninfo
 */
void vmm_fb_var_to_videomode(struct vmm_fb_videomode *mode,
			     const struct vmm_fb_var_screeninfo *var)
{
	u32 pixclock, hfreq, htotal, vtotal;

	mode->name = NULL;
	mode->xres = var->xres;
	mode->yres = var->yres;
	mode->pixclock = var->pixclock;
	mode->hsync_len = var->hsync_len;
	mode->vsync_len = var->vsync_len;
	mode->left_margin = var->left_margin;
	mode->right_margin = var->right_margin;
	mode->upper_margin = var->upper_margin;
	mode->lower_margin = var->lower_margin;
	mode->sync = var->sync;
	mode->vmode = var->vmode & FB_VMODE_MASK;
	mode->flag = FB_MODE_IS_FROM_VAR;
	mode->refresh = 0;

	if (!var->pixclock)
		return;

	pixclock = PICOS2KHZ(var->pixclock) * 1000;

	htotal = var->xres + var->right_margin + var->hsync_len +
		var->left_margin;
	vtotal = var->yres + var->lower_margin + var->vsync_len +
		var->upper_margin;

	if (var->vmode & FB_VMODE_INTERLACED)
		vtotal /= 2;
	if (var->vmode & FB_VMODE_DOUBLE)
		vtotal *= 2;

	hfreq = udiv32(pixclock, htotal);
	mode->refresh = udiv32(hfreq, vtotal);
}
VMM_EXPORT_SYMBOL(vmm_fb_var_to_videomode);

/**
 * Convert vmm_fb_videomode to vmm_fb_var_screeninfo
 * @var: pointer to struct vmm_fb_var_screeninfo
 * @mode: pointer to struct vmm_fb_videomode
 */
void vmm_fb_videomode_to_var(struct vmm_fb_var_screeninfo *var,
			 const struct vmm_fb_videomode *mode)
{
	var->xres = mode->xres;
	var->yres = mode->yres;
	var->xres_virtual = mode->xres;
	var->yres_virtual = mode->yres;
	var->xoffset = 0;
	var->yoffset = 0;
	var->pixclock = mode->pixclock;
	var->left_margin = mode->left_margin;
	var->right_margin = mode->right_margin;
	var->upper_margin = mode->upper_margin;
	var->lower_margin = mode->lower_margin;
	var->hsync_len = mode->hsync_len;
	var->vsync_len = mode->vsync_len;
	var->sync = mode->sync;
	var->vmode = mode->vmode & FB_VMODE_MASK;
}
VMM_EXPORT_SYMBOL(vmm_fb_videomode_to_var);

/**
 * Compare 2 videomodes
 * @mode1: first videomode
 * @mode2: second videomode
 *
 * RETURNS:
 * 1 if equal, 0 if not
 */
int vmm_fb_mode_is_equal(const struct vmm_fb_videomode *mode1,
			 const struct vmm_fb_videomode *mode2)
{
	return (mode1->xres         == mode2->xres &&
		mode1->yres         == mode2->yres &&
		mode1->pixclock     == mode2->pixclock &&
		mode1->hsync_len    == mode2->hsync_len &&
		mode1->vsync_len    == mode2->vsync_len &&
		mode1->left_margin  == mode2->left_margin &&
		mode1->right_margin == mode2->right_margin &&
		mode1->upper_margin == mode2->upper_margin &&
		mode1->lower_margin == mode2->lower_margin &&
		mode1->sync         == mode2->sync &&
		mode1->vmode        == mode2->vmode);
}
VMM_EXPORT_SYMBOL(vmm_fb_mode_is_equal);

/**
 * Find best matching videomode
 * @var: pointer to struct vmm_fb_var_screeninfo
 * @head: pointer to struct dlist of modelist
 *
 * RETURNS:
 * struct vmm_fb_videomode, NULL if none found
 *
 * IMPORTANT:
 * This function assumes that all modelist entries in
 * info->modelist are valid.
 *
 * NOTES:
 * Finds best matching videomode which has an equal or greater dimension than
 * var->xres and var->yres.  If more than 1 videomode is found, will return
 * the videomode with the highest refresh rate
 */
const struct vmm_fb_videomode *vmm_fb_find_best_mode(
				const struct vmm_fb_var_screeninfo *var,
				struct dlist *head)
{
	struct list_head *pos;
	struct vmm_fb_modelist *modelist;
	struct vmm_fb_videomode *mode, *best = NULL;
	u32 diff = -1;

	list_for_each(pos, head) {
		u32 d;

		modelist = list_entry(pos, struct vmm_fb_modelist, list);
		mode = &modelist->mode;

		if (mode->xres >= var->xres && mode->yres >= var->yres) {
			d = (mode->xres - var->xres) +
				(mode->yres - var->yres);
			if (diff > d) {
				diff = d;
				best = mode;
			} else if (diff == d && best &&
				   mode->refresh > best->refresh)
				best = mode;
		}
	}
	return best;
}
VMM_EXPORT_SYMBOL(vmm_fb_find_best_mode);

/**
 * Find closest videomode
 *
 * @mode: pointer to struct vmm_fb_videomode
 * @head: pointer to modelist
 *
 * Finds best matching videomode, smaller or greater in dimension.
 * If more than 1 videomode is found, will return the videomode with
 * the closest refresh rate.
 */
const struct vmm_fb_videomode *vmm_fb_find_nearest_mode(
					const struct vmm_fb_videomode *mode,
					struct dlist *head)
{
	struct list_head *pos;
	struct vmm_fb_modelist *modelist;
	struct vmm_fb_videomode *cmode, *best = NULL;
	u32 diff = -1, diff_refresh = -1;

	list_for_each(pos, head) {
		u32 d;

		modelist = list_entry(pos, struct vmm_fb_modelist, list);
		cmode = &modelist->mode;

		d = abs(cmode->xres - mode->xres) +
			abs(cmode->yres - mode->yres);
		if (diff > d) {
			diff = d;
			diff_refresh = abs(cmode->refresh - mode->refresh);
			best = cmode;
		} else if (diff == d) {
			d = abs(cmode->refresh - mode->refresh);
			if (diff_refresh > d) {
				diff_refresh = d;
				best = cmode;
			}
		}
	}

	return best;
}
VMM_EXPORT_SYMBOL(vmm_fb_find_nearest_mode);

/**
 * Find a videomode which exactly matches the timings in var
 * @var: pointer to struct vmm_fb_var_screeninfo
 * @head: pointer to struct dlist of modelist
 *
 * RETURNS:
 * struct vmm_fb_videomode, NULL if none found
 */
const struct vmm_fb_videomode *vmm_fb_match_mode(
					const struct vmm_fb_var_screeninfo *var,
					struct dlist *head)
{
	struct dlist *pos;
	struct vmm_fb_modelist *modelist;
	struct vmm_fb_videomode *m, mode;

	vmm_fb_var_to_videomode(&mode, var);
	list_for_each(pos, head) {
		modelist = list_entry(pos, struct vmm_fb_modelist, list);
		m = &modelist->mode;
		if (vmm_fb_mode_is_equal(m, &mode))
			return m;
	}
	return NULL;
}
VMM_EXPORT_SYMBOL(vmm_fb_match_mode);

/**
 * Adds videomode entry to modelist
 * @mode: videomode to add
 * @head: struct list_head of modelist
 *
 * NOTES:
 * Will only add unmatched mode entries
 */
int vmm_fb_add_videomode(const struct vmm_fb_videomode *mode, struct dlist *head)
{
	struct dlist *pos;
	struct vmm_fb_modelist *modelist;
	struct vmm_fb_videomode *m;
	int found = 0;

	list_for_each(pos, head) {
		modelist = list_entry(pos, struct vmm_fb_modelist, list);
		m = &modelist->mode;
		if (vmm_fb_mode_is_equal(m, mode)) {
			found = 1;
			break;
		}
	}
	if (!found) {
		modelist = vmm_malloc(sizeof(struct vmm_fb_modelist));

		if (!modelist)
			return VMM_ENOMEM;
		modelist->mode = *mode;
		list_add(&modelist->list, head);
	}
	return 0;
}
VMM_EXPORT_SYMBOL(vmm_fb_add_videomode);

/**
 * Removed videomode entry from modelist
 * @mode: videomode to remove
 * @head: struct list_head of modelist
 *
 * NOTES:
 * Will remove all matching mode entries
 */
void vmm_fb_delete_videomode(const struct vmm_fb_videomode *mode,
			     struct dlist *head)
{
	struct dlist *pos, *n;
	struct vmm_fb_modelist *modelist;
	struct vmm_fb_videomode *m;

	list_for_each_safe(pos, n, head) {
		modelist = list_entry(pos, struct vmm_fb_modelist, list);
		m = &modelist->mode;
		if (vmm_fb_mode_is_equal(m, mode)) {
			list_del(pos);
			vmm_free(pos);
		}
	}
}
VMM_EXPORT_SYMBOL(vmm_fb_delete_videomode);

/**
 * Destroy modelist
 * @head: struct list_head of modelist
 */
void vmm_fb_destroy_modelist(struct dlist *head)
{
	struct dlist *pos, *n;

	list_for_each_safe(pos, n, head) {
		list_del(pos);
		vmm_free(pos);
	}
}
VMM_EXPORT_SYMBOL(vmm_fb_destroy_modelist);

/**
 * Convert mode array to mode list
 * @modedb: array of struct vmm_fb_videomode
 * @num: number of entries in array
 * @head: struct list_head of modelist
 */
void vmm_fb_videomode_to_modelist(const struct vmm_fb_videomode *modedb, 
				  int num, struct dlist *head)
{
	int i;

	INIT_LIST_HEAD(head);

	for (i = 0; i < num; i++) {
		if (vmm_fb_add_videomode(&modedb[i], head))
			return;
	}
}
VMM_EXPORT_SYMBOL(vmm_fb_videomode_to_modelist);

const struct vmm_fb_videomode *vmm_fb_find_best_display(
					const struct vmm_fb_monspecs *specs,
					struct dlist *head)
{
	struct dlist *pos;
	struct vmm_fb_modelist *modelist;
	const struct vmm_fb_videomode *m, *m1 = NULL, *md = NULL, *best = NULL;
	int first = 0;

	if (!head->prev || !head->next || list_empty(head))
		goto finished;

	/* get the first detailed mode and the very first mode */
	list_for_each(pos, head) {
		modelist = list_entry(pos, struct vmm_fb_modelist, list);
		m = &modelist->mode;

		if (!first) {
			m1 = m;
			first = 1;
		}

		if (m->flag & FB_MODE_IS_FIRST) {
 			md = m;
			break;
		}
	}

	/* first detailed timing is preferred */
	if (specs->misc & FB_MISC_1ST_DETAIL) {
		best = md;
		goto finished;
	}

	/* find best mode based on display width and height */
	if (specs->max_x && specs->max_y) {
		struct vmm_fb_var_screeninfo var;

		memset(&var, 0, sizeof(struct vmm_fb_var_screeninfo));
		var.xres = (specs->max_x * 7200)/254;
		var.yres = (specs->max_y * 7200)/254;
		m = vmm_fb_find_best_mode(&var, head);
		if (m) {
			best = m;
			goto finished;
		}
	}

	/* use first detailed mode */
	if (md) {
		best = md;
		goto finished;
	}

	/* last resort, use the very first mode */
	best = m1;
finished:
	return best;
}
VMM_EXPORT_SYMBOL(vmm_fb_find_best_display);

