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vbe.c revision 1.5.4.2
      1  1.5.4.2     rmind /* $NetBSD: vbe.c,v 1.5.4.2 2011/03/05 20:50:45 rmind Exp $ */
      2      1.1  jmcneill 
      3      1.1  jmcneill /*-
      4      1.1  jmcneill  * Copyright (c) 2009 Jared D. McNeill <jmcneill (at) invisible.ca>
      5      1.1  jmcneill  * All rights reserved.
      6      1.1  jmcneill  *
      7      1.1  jmcneill  * Redistribution and use in source and binary forms, with or without
      8      1.1  jmcneill  * modification, are permitted provided that the following conditions
      9      1.1  jmcneill  * are met:
     10      1.1  jmcneill  * 1. Redistributions of source code must retain the above copyright
     11      1.1  jmcneill  *    notice, this list of conditions and the following disclaimer.
     12      1.1  jmcneill  * 2. Redistributions in binary form must reproduce the above copyright
     13      1.1  jmcneill  *    notice, this list of conditions and the following disclaimer in the
     14      1.1  jmcneill  *    documentation and/or other materials provided with the distribution.
     15      1.1  jmcneill  *
     16      1.1  jmcneill  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     17      1.1  jmcneill  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     18      1.1  jmcneill  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     19      1.1  jmcneill  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     20      1.1  jmcneill  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     21      1.1  jmcneill  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     22      1.1  jmcneill  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     23      1.1  jmcneill  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     24      1.1  jmcneill  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     25      1.1  jmcneill  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     26      1.1  jmcneill  * POSSIBILITY OF SUCH DAMAGE.
     27      1.1  jmcneill  */
     28      1.1  jmcneill 
     29      1.1  jmcneill /*
     30      1.1  jmcneill  * VESA BIOS Extensions routines
     31      1.1  jmcneill  */
     32      1.1  jmcneill 
     33      1.1  jmcneill #include <lib/libsa/stand.h>
     34      1.1  jmcneill #include <lib/libkern/libkern.h>
     35      1.1  jmcneill #include <machine/bootinfo.h>
     36      1.1  jmcneill #include "libi386.h"
     37      1.1  jmcneill #include "vbe.h"
     38      1.1  jmcneill 
     39      1.1  jmcneill extern const uint8_t rasops_cmap[];
     40  1.5.4.2     rmind static uint8_t *vbe_edid = NULL;
     41  1.5.4.2     rmind static int vbe_edid_valid = 0;
     42      1.1  jmcneill 
     43      1.1  jmcneill static struct _vbestate {
     44      1.1  jmcneill 	int		available;
     45      1.4  jmcneill 	int		modenum;
     46      1.1  jmcneill } vbestate;
     47      1.1  jmcneill 
     48      1.1  jmcneill static int
     49      1.1  jmcneill vbe_mode_is_supported(struct modeinfoblock *mi)
     50      1.1  jmcneill {
     51      1.1  jmcneill 	if ((mi->ModeAttributes & 0x01) == 0)
     52      1.1  jmcneill 		return 0;	/* mode not supported by hardware */
     53      1.1  jmcneill 	if ((mi->ModeAttributes & 0x08) == 0)
     54      1.1  jmcneill 		return 0;	/* linear fb not available */
     55      1.1  jmcneill 	if ((mi->ModeAttributes & 0x10) == 0)
     56      1.1  jmcneill 		return 0;	/* text mode */
     57      1.1  jmcneill 	if (mi->NumberOfPlanes != 1)
     58      1.1  jmcneill 		return 0;	/* planar mode not supported */
     59      1.1  jmcneill 	if (mi->MemoryModel != 0x04 /* Packed pixel */ &&
     60      1.1  jmcneill 	    mi->MemoryModel != 0x06 /* Direct Color */)
     61      1.1  jmcneill 		return 0;	/* unsupported pixel format */
     62      1.1  jmcneill 	return 1;
     63      1.1  jmcneill }
     64      1.1  jmcneill 
     65      1.5  jmcneill static bool
     66      1.5  jmcneill vbe_check(void)
     67      1.5  jmcneill {
     68      1.5  jmcneill 	if (!vbestate.available) {
     69      1.5  jmcneill 		printf("VBE not available\n");
     70      1.5  jmcneill 		return false;
     71      1.5  jmcneill 	}
     72      1.5  jmcneill 	return true;
     73      1.5  jmcneill }
     74      1.5  jmcneill 
     75      1.1  jmcneill void
     76      1.1  jmcneill vbe_init(void)
     77      1.1  jmcneill {
     78      1.1  jmcneill 	struct vbeinfoblock vbe;
     79      1.1  jmcneill 
     80      1.1  jmcneill 	memset(&vbe, 0, sizeof(vbe));
     81      1.1  jmcneill 	memcpy(vbe.VbeSignature, "VBE2", 4);
     82      1.1  jmcneill 	if (biosvbe_info(&vbe) != 0x004f)
     83      1.1  jmcneill 		return;
     84      1.5  jmcneill 	if (memcmp(vbe.VbeSignature, "VESA", 4) != 0)
     85      1.1  jmcneill 		return;
     86      1.1  jmcneill 
     87      1.1  jmcneill 	vbestate.available = 1;
     88      1.4  jmcneill 	vbestate.modenum = 0;
     89      1.1  jmcneill }
     90      1.1  jmcneill 
     91      1.1  jmcneill int
     92      1.1  jmcneill vbe_available(void)
     93      1.1  jmcneill {
     94      1.1  jmcneill 	return vbestate.available;
     95      1.1  jmcneill }
     96      1.1  jmcneill 
     97      1.1  jmcneill int
     98      1.1  jmcneill vbe_set_palette(const uint8_t *cmap, int slot)
     99      1.1  jmcneill {
    100      1.1  jmcneill 	struct paletteentry pe;
    101      1.1  jmcneill 	int ret;
    102      1.1  jmcneill 
    103      1.5  jmcneill 	if (!vbe_check())
    104      1.1  jmcneill 		return 1;
    105      1.1  jmcneill 
    106      1.1  jmcneill 	pe.Blue = cmap[2] >> 2;
    107      1.1  jmcneill 	pe.Green = cmap[1] >> 2;
    108      1.1  jmcneill 	pe.Red = cmap[0] >> 2;
    109      1.1  jmcneill 	pe.Alignment = 0;
    110      1.1  jmcneill 
    111      1.1  jmcneill 	ret = biosvbe_palette_data(0x0600, slot, &pe);
    112      1.1  jmcneill 
    113      1.1  jmcneill 	return ret == 0x004f ? 0 : 1;
    114      1.1  jmcneill }
    115      1.1  jmcneill 
    116      1.1  jmcneill int
    117      1.1  jmcneill vbe_set_mode(int modenum)
    118      1.1  jmcneill {
    119      1.1  jmcneill 	struct modeinfoblock mi;
    120      1.1  jmcneill 	struct btinfo_framebuffer fb;
    121      1.1  jmcneill 	int ret, i;
    122      1.1  jmcneill 
    123      1.5  jmcneill 	if (!vbe_check())
    124      1.1  jmcneill 		return 1;
    125      1.1  jmcneill 
    126      1.1  jmcneill 	ret = biosvbe_get_mode_info(modenum, &mi);
    127      1.1  jmcneill 	if (ret != 0x004f) {
    128      1.5  jmcneill 		printf("mode 0x%x invalid\n", modenum);
    129      1.1  jmcneill 		return 1;
    130      1.1  jmcneill 	}
    131      1.1  jmcneill 
    132      1.1  jmcneill 	if (!vbe_mode_is_supported(&mi)) {
    133      1.5  jmcneill 		printf("mode 0x%x not supported\n", modenum);
    134      1.1  jmcneill 		return 1;
    135      1.1  jmcneill 	}
    136      1.1  jmcneill 
    137      1.1  jmcneill 	ret = biosvbe_set_mode(modenum);
    138      1.1  jmcneill 	if (ret != 0x004f) {
    139      1.5  jmcneill 		printf("mode 0x%x could not be set\n", modenum);
    140      1.1  jmcneill 		return 1;
    141      1.1  jmcneill 	}
    142      1.1  jmcneill 
    143      1.1  jmcneill 	/* Setup palette for packed pixel mode */
    144      1.1  jmcneill 	if (mi.MemoryModel == 0x04)
    145      1.1  jmcneill 		for (i = 0; i < 256; i++)
    146      1.1  jmcneill 			vbe_set_palette(&rasops_cmap[i * 3], i);
    147      1.1  jmcneill 
    148      1.1  jmcneill 	fb.physaddr = (uint64_t)mi.PhysBasePtr & 0xffffffff;
    149      1.1  jmcneill 	fb.width = mi.XResolution;
    150      1.1  jmcneill 	fb.height = mi.YResolution;
    151      1.1  jmcneill 	fb.stride = mi.BytesPerScanLine;
    152      1.1  jmcneill 	fb.depth = mi.BitsPerPixel;
    153      1.1  jmcneill 	fb.flags = 0;
    154      1.1  jmcneill 	fb.rnum = mi.RedMaskSize;
    155      1.1  jmcneill 	fb.rpos = mi.RedFieldPosition;
    156      1.1  jmcneill 	fb.gnum = mi.GreenMaskSize;
    157      1.1  jmcneill 	fb.gpos = mi.GreenFieldPosition;
    158      1.1  jmcneill 	fb.bnum = mi.BlueMaskSize;
    159      1.1  jmcneill 	fb.bpos = mi.BlueFieldPosition;
    160      1.3  jmcneill 	fb.vbemode = modenum;
    161      1.1  jmcneill 
    162      1.1  jmcneill 	framebuffer_configure(&fb);
    163      1.1  jmcneill 
    164      1.1  jmcneill 	return 0;
    165      1.1  jmcneill }
    166      1.1  jmcneill 
    167      1.4  jmcneill int
    168      1.4  jmcneill vbe_commit(void)
    169      1.4  jmcneill {
    170      1.4  jmcneill 	int ret = 1;
    171      1.4  jmcneill 
    172      1.4  jmcneill 	if (vbestate.modenum > 0) {
    173      1.4  jmcneill 		ret = vbe_set_mode(vbestate.modenum);
    174      1.4  jmcneill 		if (ret) {
    175      1.5  jmcneill 			printf("WARNING: failed to set VBE mode 0x%x\n",
    176      1.4  jmcneill 			    vbestate.modenum);
    177  1.5.4.1     rmind 			wait_sec(5);
    178      1.4  jmcneill 		}
    179      1.4  jmcneill 	}
    180      1.4  jmcneill 	return ret;
    181      1.4  jmcneill }
    182      1.4  jmcneill 
    183      1.1  jmcneill static void *
    184      1.1  jmcneill vbe_farptr(uint32_t farptr)
    185      1.1  jmcneill {
    186      1.1  jmcneill 	return VBEPHYPTR((((farptr & 0xffff0000) >> 12) + (farptr & 0xffff)));
    187      1.1  jmcneill }
    188      1.1  jmcneill 
    189      1.1  jmcneill static int
    190  1.5.4.2     rmind vbe_parse_mode_str(char *str, int *x, int *y, int *depth)
    191      1.1  jmcneill {
    192      1.1  jmcneill 	char *p;
    193      1.1  jmcneill 
    194      1.1  jmcneill 	p = str;
    195      1.1  jmcneill 	*x = strtoul(p, NULL, 0);
    196      1.1  jmcneill 	if (*x == 0)
    197      1.1  jmcneill 		return 0;
    198      1.1  jmcneill 	p = strchr(p, 'x');
    199      1.1  jmcneill 	if (!p)
    200      1.1  jmcneill 		return 0;
    201      1.1  jmcneill 	++p;
    202      1.1  jmcneill 	*y = strtoul(p, NULL, 0);
    203      1.1  jmcneill 	if (*y == 0)
    204      1.1  jmcneill 		return 0;
    205      1.1  jmcneill 	p = strchr(p, 'x');
    206      1.1  jmcneill 	if (!p)
    207  1.5.4.2     rmind 		*depth = 8;
    208      1.1  jmcneill 	else {
    209      1.1  jmcneill 		++p;
    210  1.5.4.2     rmind 		*depth = strtoul(p, NULL, 0);
    211  1.5.4.2     rmind 		if (*depth == 0)
    212      1.1  jmcneill 			return 0;
    213      1.1  jmcneill 	}
    214      1.1  jmcneill 
    215      1.1  jmcneill 	return 1;
    216      1.1  jmcneill }
    217      1.1  jmcneill 
    218      1.1  jmcneill static int
    219  1.5.4.2     rmind vbe_find_mode_xyd(int x, int y, int depth)
    220      1.1  jmcneill {
    221      1.1  jmcneill 	struct vbeinfoblock vbe;
    222      1.1  jmcneill 	struct modeinfoblock mi;
    223      1.1  jmcneill 	uint32_t farptr;
    224      1.1  jmcneill 	uint16_t mode;
    225      1.1  jmcneill 	int safety = 0;
    226      1.1  jmcneill 
    227      1.1  jmcneill 	memset(&vbe, 0, sizeof(vbe));
    228      1.1  jmcneill 	memcpy(vbe.VbeSignature, "VBE2", 4);
    229      1.1  jmcneill 	if (biosvbe_info(&vbe) != 0x004f)
    230      1.1  jmcneill 		return 0;
    231      1.1  jmcneill 	if (memcmp(vbe.VbeSignature, "VESA", 4) != 0)
    232      1.1  jmcneill 		return 0;
    233      1.1  jmcneill 	farptr = vbe.VideoModePtr;
    234      1.1  jmcneill 	if (farptr == 0)
    235      1.1  jmcneill 		return 0;
    236      1.1  jmcneill 
    237      1.1  jmcneill 	while ((mode = *(uint16_t *)vbe_farptr(farptr)) != 0xffff) {
    238      1.1  jmcneill 		safety++;
    239      1.1  jmcneill 		farptr += 2;
    240      1.1  jmcneill 		if (safety == 100)
    241      1.1  jmcneill 			return 0;
    242      1.1  jmcneill 		if (biosvbe_get_mode_info(mode, &mi) != 0x004f)
    243      1.1  jmcneill 			continue;
    244      1.1  jmcneill 		/* we only care about linear modes here */
    245      1.1  jmcneill 		if (vbe_mode_is_supported(&mi) == 0)
    246      1.1  jmcneill 			continue;
    247      1.1  jmcneill 		safety = 0;
    248      1.1  jmcneill 		if (mi.XResolution == x &&
    249      1.1  jmcneill 		    mi.YResolution == y &&
    250  1.5.4.2     rmind 		    mi.BitsPerPixel == depth)
    251      1.1  jmcneill 			return mode;
    252      1.1  jmcneill 	}
    253      1.1  jmcneill 
    254      1.1  jmcneill 	return 0;
    255      1.1  jmcneill }
    256      1.1  jmcneill 
    257  1.5.4.2     rmind static int
    258  1.5.4.2     rmind vbe_find_mode(char *str)
    259  1.5.4.2     rmind {
    260  1.5.4.2     rmind 	int x, y, depth;
    261  1.5.4.2     rmind 
    262  1.5.4.2     rmind 	if (!vbe_parse_mode_str(str, &x, &y, &depth))
    263  1.5.4.2     rmind 		return 0;
    264  1.5.4.2     rmind 
    265  1.5.4.2     rmind 	return vbe_find_mode_xyd(x, y, depth);
    266  1.5.4.2     rmind }
    267  1.5.4.2     rmind 
    268      1.1  jmcneill static void
    269      1.1  jmcneill vbe_dump_mode(int modenum, struct modeinfoblock *mi)
    270      1.1  jmcneill {
    271      1.1  jmcneill 	printf("0x%x=%dx%dx%d", modenum,
    272      1.1  jmcneill 	    mi->XResolution, mi->YResolution, mi->BitsPerPixel);
    273      1.1  jmcneill }
    274      1.1  jmcneill 
    275  1.5.4.2     rmind static int
    276  1.5.4.2     rmind vbe_get_edid(int *pwidth, int *pheight)
    277  1.5.4.2     rmind {
    278  1.5.4.2     rmind 	const uint8_t magic[] = EDID_MAGIC;
    279  1.5.4.2     rmind 	int ddc_caps, ret;
    280  1.5.4.2     rmind 
    281  1.5.4.2     rmind 	ddc_caps = biosvbe_ddc_caps();
    282  1.5.4.2     rmind 	if (ddc_caps == 0) {
    283  1.5.4.2     rmind 		return 1;
    284  1.5.4.2     rmind 	}
    285  1.5.4.2     rmind 
    286  1.5.4.2     rmind 	if (vbe_edid == NULL) {
    287  1.5.4.2     rmind 		vbe_edid = alloc(128);
    288  1.5.4.2     rmind 	}
    289  1.5.4.2     rmind 	if (vbe_edid_valid == 0) {
    290  1.5.4.2     rmind 		ret = biosvbe_ddc_read_edid(0, vbe_edid);
    291  1.5.4.2     rmind 		if (ret != 0x004f)
    292  1.5.4.2     rmind 			return 1;
    293  1.5.4.2     rmind 		if (memcmp(vbe_edid, magic, sizeof(magic)) != 0)
    294  1.5.4.2     rmind 			return 1;
    295  1.5.4.2     rmind 		vbe_edid_valid = 1;
    296  1.5.4.2     rmind 	}
    297  1.5.4.2     rmind 
    298  1.5.4.2     rmind 	*pwidth = vbe_edid[EDID_DESC_BLOCK + 2] |
    299  1.5.4.2     rmind 	    (((int)vbe_edid[EDID_DESC_BLOCK + 4] & 0xf0) << 4);
    300  1.5.4.2     rmind 	*pheight = vbe_edid[EDID_DESC_BLOCK + 5] |
    301  1.5.4.2     rmind 	    (((int)vbe_edid[EDID_DESC_BLOCK + 7] & 0xf0) << 4);
    302  1.5.4.2     rmind 
    303  1.5.4.2     rmind 	return 0;
    304  1.5.4.2     rmind }
    305  1.5.4.2     rmind 
    306      1.1  jmcneill void
    307      1.1  jmcneill vbe_modelist(void)
    308      1.1  jmcneill {
    309      1.1  jmcneill 	struct vbeinfoblock vbe;
    310      1.1  jmcneill 	struct modeinfoblock mi;
    311      1.1  jmcneill 	uint32_t farptr;
    312      1.1  jmcneill 	uint16_t mode;
    313      1.1  jmcneill 	int nmodes = 0, safety = 0;
    314  1.5.4.2     rmind 	int ddc_caps, edid_width, edid_height;
    315      1.1  jmcneill 
    316      1.5  jmcneill 	if (!vbe_check())
    317      1.1  jmcneill 		return;
    318      1.1  jmcneill 
    319  1.5.4.2     rmind 	ddc_caps = biosvbe_ddc_caps();
    320  1.5.4.2     rmind 	if (ddc_caps & 3) {
    321  1.5.4.2     rmind 		printf("DDC");
    322  1.5.4.2     rmind 		if (ddc_caps & 1)
    323  1.5.4.2     rmind 			printf(" [DDC1]");
    324  1.5.4.2     rmind 		if (ddc_caps & 2)
    325  1.5.4.2     rmind 			printf(" [DDC2]");
    326  1.5.4.2     rmind 
    327  1.5.4.2     rmind 		if (vbe_get_edid(&edid_width, &edid_height) != 0)
    328  1.5.4.2     rmind 			printf(": no EDID information\n");
    329  1.5.4.2     rmind 		else
    330  1.5.4.2     rmind 			printf(": EDID %dx%d\n", edid_width, edid_height);
    331  1.5.4.2     rmind 	}
    332  1.5.4.2     rmind 
    333      1.1  jmcneill 	printf("Modes: ");
    334      1.1  jmcneill 	memset(&vbe, 0, sizeof(vbe));
    335      1.1  jmcneill 	memcpy(vbe.VbeSignature, "VBE2", 4);
    336      1.1  jmcneill 	if (biosvbe_info(&vbe) != 0x004f)
    337      1.1  jmcneill 		goto done;
    338      1.1  jmcneill 	if (memcmp(vbe.VbeSignature, "VESA", 4) != 0)
    339      1.1  jmcneill 		goto done;
    340      1.1  jmcneill 	farptr = vbe.VideoModePtr;
    341      1.1  jmcneill 	if (farptr == 0)
    342      1.1  jmcneill 		goto done;
    343      1.1  jmcneill 
    344      1.1  jmcneill 	while ((mode = *(uint16_t *)vbe_farptr(farptr)) != 0xffff) {
    345      1.1  jmcneill 		safety++;
    346      1.1  jmcneill 		farptr += 2;
    347      1.1  jmcneill 		if (safety == 100) {
    348      1.5  jmcneill 			printf("[?] ");
    349      1.1  jmcneill 			break;
    350      1.1  jmcneill 		}
    351      1.1  jmcneill 		if (biosvbe_get_mode_info(mode, &mi) != 0x004f)
    352      1.1  jmcneill 			continue;
    353      1.1  jmcneill 		/* we only care about linear modes here */
    354      1.1  jmcneill 		if (vbe_mode_is_supported(&mi) == 0)
    355      1.1  jmcneill 			continue;
    356      1.1  jmcneill 		safety = 0;
    357      1.1  jmcneill 		if (nmodes % 4 == 0)
    358      1.1  jmcneill 			printf("\n");
    359      1.1  jmcneill 		else
    360      1.1  jmcneill 			printf("  ");
    361      1.1  jmcneill 		vbe_dump_mode(mode, &mi);
    362      1.1  jmcneill 		nmodes++;
    363      1.1  jmcneill 	}
    364      1.1  jmcneill 
    365      1.1  jmcneill done:
    366      1.1  jmcneill 	if (nmodes == 0)
    367      1.1  jmcneill 		printf("none found");
    368      1.1  jmcneill 	printf("\n");
    369      1.1  jmcneill }
    370      1.1  jmcneill 
    371      1.1  jmcneill void
    372      1.1  jmcneill command_vesa(char *cmd)
    373      1.1  jmcneill {
    374      1.1  jmcneill 	char arg[20];
    375  1.5.4.2     rmind 	int modenum, edid_width, edid_height;
    376      1.1  jmcneill 
    377      1.5  jmcneill 	if (!vbe_check())
    378      1.1  jmcneill 		return;
    379      1.1  jmcneill 
    380      1.1  jmcneill 	strlcpy(arg, cmd, sizeof(arg));
    381      1.1  jmcneill 
    382      1.1  jmcneill 	if (strcmp(arg, "list") == 0) {
    383      1.1  jmcneill 		vbe_modelist();
    384      1.1  jmcneill 		return;
    385      1.1  jmcneill 	}
    386      1.1  jmcneill 
    387      1.1  jmcneill 	if (strcmp(arg, "disabled") == 0 || strcmp(arg, "off") == 0) {
    388      1.4  jmcneill 		vbestate.modenum = 0;
    389      1.1  jmcneill 		return;
    390      1.1  jmcneill 	}
    391      1.1  jmcneill 
    392  1.5.4.2     rmind 	if (strcmp(arg, "enabled") == 0 || strcmp(arg, "on") == 0) {
    393  1.5.4.2     rmind 		if (vbe_get_edid(&edid_width, &edid_height) != 0) {
    394  1.5.4.2     rmind 			modenum = VBE_DEFAULT_MODE;
    395  1.5.4.2     rmind 		} else {
    396  1.5.4.2     rmind 			modenum = vbe_find_mode_xyd(edid_width, edid_height, 8);
    397  1.5.4.2     rmind 			if (modenum == 0)
    398  1.5.4.2     rmind 				modenum = VBE_DEFAULT_MODE;
    399  1.5.4.2     rmind 		}
    400  1.5.4.2     rmind 	} else if (strncmp(arg, "0x", 2) == 0) {
    401      1.2  jmcneill 		modenum = strtoul(arg, NULL, 0);
    402  1.5.4.2     rmind 	} else if (strchr(arg, 'x') != NULL) {
    403      1.1  jmcneill 		modenum = vbe_find_mode(arg);
    404      1.4  jmcneill 		if (modenum == 0) {
    405      1.4  jmcneill 			printf("mode %s not supported by firmware\n", arg);
    406      1.1  jmcneill 			return;
    407      1.4  jmcneill 		}
    408  1.5.4.2     rmind 	} else {
    409      1.2  jmcneill 		modenum = 0;
    410  1.5.4.2     rmind 	}
    411      1.2  jmcneill 
    412      1.1  jmcneill 	if (modenum >= 0x100) {
    413      1.4  jmcneill 		vbestate.modenum = modenum;
    414      1.1  jmcneill 		return;
    415      1.1  jmcneill 	}
    416      1.1  jmcneill 
    417      1.5  jmcneill 	printf("invalid flag, must be 'on', 'off', "
    418      1.5  jmcneill 	    "a display mode, or a VBE mode number\n");
    419      1.1  jmcneill }
    420