/*
 * Copyright (c) 2009 Jared D. McNeill <jmcneill@invisible.ca>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * VESA BIOS Extensions routines
 */

#include <stand.h>
#include <stdbool.h>
#include <bootstrap.h>
#include <machine/bootinfo.h>
#include <machine/metadata.h>
#include <sys/multiboot2.h>
#include <btxv86.h>
#include "libi386.h"
#include "gfx_fb.h"     /* for EDID */
#include "vbe.h"
#include <sys/font.h>
#include <sys/rgb.h>
#include <sys/vgareg.h>
#include <sys/vgasubr.h>

multiboot_tag_vbe_t vbestate;
static struct vbeinfoblock *vbe =
        (struct vbeinfoblock *)&vbestate.vbe_control_info;
static struct modeinfoblock *vbe_mode =
        (struct modeinfoblock *)&vbestate.vbe_mode_info;
static uint16_t *vbe_mode_list;
static size_t vbe_mode_list_size;
struct vesa_edid_info *edid_info = NULL;
multiboot_color_t *cmap;
/* The default VGA color palette format is 6 bits per primary color. */
int palette_format = 6;

#define VESA_MODE_BASE          0x100
#define VESA_END_OF_MODE_LIST   0xffff

/* Actually assuming mode 3. */
void
bios_set_text_mode(int mode)
{
        int atr;

        if (vbe->Capabilities & VBE_CAP_DAC8) {
                int m;

                /*
                 * The mode change should reset the palette format to
                 * 6 bits, but apparently some systems do fail with 8-bit
                 * palette, so we switch to 6-bit here.
                 */
                m = 0x0600;
                (void) biosvbe_palette_format(&m);
                palette_format = m;
        }
        v86.ctl = V86_FLAGS;
        v86.addr = 0x10;
        v86.eax = mode;                         /* set VGA text mode */
        v86int();
        atr = vga_get_atr(VGA_REG_ADDR, VGA_ATR_MODE);
        atr &= ~VGA_ATR_MODE_BLINK;
        atr &= ~VGA_ATR_MODE_9WIDE;
        vga_set_atr(VGA_REG_ADDR, VGA_ATR_MODE, atr);

        vbestate.vbe_mode = 0;                  /* vbe is disabled */
        gfx_fb.framebuffer_common.framebuffer_type =
            MULTIBOOT_FRAMEBUFFER_TYPE_EGA_TEXT;
        /* 16 bits per character */
        gfx_fb.framebuffer_common.framebuffer_bpp = 16;
        gfx_fb.framebuffer_common.framebuffer_addr =
            VGA_MEM_ADDR + VGA_COLOR_BASE;
        gfx_fb.framebuffer_common.framebuffer_width = TEXT_COLS;
        gfx_fb.framebuffer_common.framebuffer_height = TEXT_ROWS;
        gfx_fb.framebuffer_common.framebuffer_pitch = TEXT_COLS * 2;
}

/* Function 00h - Return VBE Controller Information */
static int
biosvbe_info(struct vbeinfoblock *vbe)
{
        v86.ctl = V86_FLAGS;
        v86.addr = 0x10;
        v86.eax = 0x4f00;
        v86.es = VTOPSEG(vbe);
        v86.edi = VTOPOFF(vbe);
        v86int();
        return (v86.eax & 0xffff);
}

/* Function 01h - Return VBE Mode Information */
static int
biosvbe_get_mode_info(int mode, struct modeinfoblock *mi)
{
        v86.ctl = V86_FLAGS;
        v86.addr = 0x10;
        v86.eax = 0x4f01;
        v86.ecx = mode;
        v86.es = VTOPSEG(mi);
        v86.edi = VTOPOFF(mi);
        v86int();
        return (v86.eax & 0xffff);
}

/* Function 02h - Set VBE Mode */
static int
biosvbe_set_mode(int mode, struct crtciinfoblock *ci)
{
        int rv;

        if (vbe->Capabilities & VBE_CAP_DAC8) {
                int m;

                /*
                 * The mode change should reset the palette format to
                 * 6 bits, but apparently some systems do fail with 8-bit
                 * palette, so we switch to 6-bit here.
                 */
                m = 0x0600;
                if (biosvbe_palette_format(&m) == VBE_SUCCESS)
                        palette_format = m;
        }
        v86.ctl = V86_FLAGS;
        v86.addr = 0x10;
        v86.eax = 0x4f02;
        v86.ebx = mode | 0x4000;        /* set linear FB bit */
        v86.es = VTOPSEG(ci);
        v86.edi = VTOPOFF(ci);
        v86int();
        rv = v86.eax & 0xffff;
        if (vbe->Capabilities & VBE_CAP_DAC8) {
                int m;

                /* Switch to 8-bits per primary color. */
                m = 0x0800;
                if (biosvbe_palette_format(&m) == VBE_SUCCESS)
                        palette_format = m;
        }
        return (rv);
}

/* Function 03h - Get VBE Mode */
static int
biosvbe_get_mode(int *mode)
{
        v86.ctl = V86_FLAGS;
        v86.addr = 0x10;
        v86.eax = 0x4f03;
        v86int();
        *mode = v86.ebx & 0x3fff;       /* Bits 0-13 */
        return (v86.eax & 0xffff);
}

/* Function 08h - Set/Get DAC Palette Format */
int
biosvbe_palette_format(int *format)
{
        v86.ctl = V86_FLAGS;
        v86.addr = 0x10;
        v86.eax = 0x4f08;
        v86.ebx = *format;
        v86int();
        *format = (v86.ebx >> 8) & 0xff;
        return (v86.eax & 0xffff);
}

/* Function 09h - Set/Get Palette Data */
static int
biosvbe_palette_data(int mode, int reg, struct paletteentry *pe)
{
        v86.ctl = V86_FLAGS;
        v86.addr = 0x10;
        v86.eax = 0x4f09;
        v86.ebx = mode;
        v86.edx = reg;
        v86.ecx = 1;
        v86.es = VTOPSEG(pe);
        v86.edi = VTOPOFF(pe);
        v86int();
        return (v86.eax & 0xffff);
}

/*
 * Function 15h BL=00h - Report VBE/DDC Capabilities
 *
 * int biosvbe_ddc_caps(void)
 * return: VBE/DDC capabilities
 */
static int
biosvbe_ddc_caps(void)
{
        v86.ctl = V86_FLAGS;
        v86.addr = 0x10;
        v86.eax = 0x4f15;       /* display identification extensions */
        v86.ebx = 0;            /* report DDC capabilities */
        v86.ecx = 0;            /* controller unit number (00h = primary) */
        v86.es = 0;
        v86.edi = 0;
        v86int();
        if (VBE_ERROR(v86.eax & 0xffff))
                return (0);
        return (v86.ebx & 0xffff);
}

/* Function 11h BL=01h - Flat Panel status */
static int
biosvbe_ddc_read_flat_panel_info(void *buf)
{
        v86.ctl = V86_FLAGS;
        v86.addr = 0x10;
        v86.eax = 0x4f11;       /* Flat Panel Interface extensions */
        v86.ebx = 1;            /* Return Flat Panel Information */
        v86.es = VTOPSEG(buf);
        v86.edi = VTOPOFF(buf);
        v86int();
        return (v86.eax & 0xffff);
}

/* Function 15h BL=01h - Read EDID */
static int
biosvbe_ddc_read_edid(int blockno, void *buf)
{
        v86.ctl = V86_FLAGS;
        v86.addr = 0x10;
        v86.eax = 0x4f15;       /* display identification extensions */
        v86.ebx = 1;            /* read EDID */
        v86.ecx = 0;            /* controller unit number (00h = primary) */
        v86.edx = blockno;
        v86.es = VTOPSEG(buf);
        v86.edi = VTOPOFF(buf);
        v86int();
        return (v86.eax & 0xffff);
}

static int
vbe_mode_is_supported(struct modeinfoblock *mi)
{
        if ((mi->ModeAttributes & 0x01) == 0)
                return (0);     /* mode not supported by hardware */
        if ((mi->ModeAttributes & 0x08) == 0)
                return (0);     /* linear fb not available */
        if ((mi->ModeAttributes & 0x10) == 0)
                return (0);     /* text mode */
        if (mi->NumberOfPlanes != 1)
                return (0);     /* planar mode not supported */
        if (mi->MemoryModel != 0x04 /* Packed pixel */ &&
            mi->MemoryModel != 0x06 /* Direct Color */)
                return (0);     /* unsupported pixel format */
        return (1);
}

static int
vbe_check(void)
{
        if (vbestate.mb_type != MULTIBOOT_TAG_TYPE_VBE) {
                printf("VBE not available\n");
                return (0);
        }
        return (1);
}

/*
 * Translate selector:offset style address to linear adress.
 * selector = farptr >> 16;
 * offset = farptr & 0xffff;
 * linear = (selector * 4) + offset.
 * By using mask 0xffff0000, we wil get the optimised line below.
 * As a final step, translate physical address to loader virtual address.
 */
static void *
vbe_farptr(uint32_t farptr)
{
        return (PTOV((((farptr & 0xffff0000) >> 12) + (farptr & 0xffff))));
}

void
vbe_init(void)
{
        uint16_t *p, *ml;

        /* First set FB for text mode. */
        gfx_fb.framebuffer_common.mb_type = MULTIBOOT_TAG_TYPE_FRAMEBUFFER;
        gfx_fb.framebuffer_common.framebuffer_type =
            MULTIBOOT_FRAMEBUFFER_TYPE_EGA_TEXT;
        /* 16 bits per character */
        gfx_fb.framebuffer_common.framebuffer_bpp = 16;
        gfx_fb.framebuffer_common.framebuffer_addr =
            VGA_MEM_ADDR + VGA_COLOR_BASE;
        gfx_fb.framebuffer_common.framebuffer_width = TEXT_COLS;
        gfx_fb.framebuffer_common.framebuffer_height = TEXT_ROWS;
        gfx_fb.framebuffer_common.framebuffer_pitch = TEXT_COLS * 2;

        /* Now check if we have vesa. */
        memset(vbe, 0, sizeof (*vbe));
        memcpy(vbe->VbeSignature, "VBE2", 4);
        if (biosvbe_info(vbe) != VBE_SUCCESS)
                return;
        if (memcmp(vbe->VbeSignature, "VESA", 4) != 0)
                return;

        /*
         * Copy mode list array. We must do this because some systems do
         * place this array to scratch memory, which will be reused by
         * subsequent VBE calls. (vbox 6.1 is one example).
         */
        p = ml = vbe_farptr(vbe->VideoModePtr);
        while (*p++ != VESA_END_OF_MODE_LIST)
                ;

        vbe_mode_list_size = (uintptr_t)p - (uintptr_t)ml;

        /*
         * Since vbe_init() is used only once at very start of the loader,
         * we assume malloc will not fail there. But in case it does,
         * we point vbe_mode_list to memory pointed by VideoModePtr.
         * If the VideoModePtr memory area is not valid, we will fail to
         * pick usable VBE mode and fall back to use text mode.
         */
        vbe_mode_list = malloc(vbe_mode_list_size);
        if (vbe_mode_list == NULL)
                vbe_mode_list = ml;
        else
                bcopy(ml, vbe_mode_list, vbe_mode_list_size);

        /* reset VideoModePtr, to make sure, we only do use vbe_mode_list. */
        vbe->VideoModePtr = 0;

        vbestate.mb_type = MULTIBOOT_TAG_TYPE_VBE;
        vbestate.mb_size = sizeof (vbestate);
        vbestate.vbe_mode = 0;

        /* vbe_set_mode() will set up the rest. */
}

int
vbe_available(void)
{
        return (vbestate.mb_type);
}

int
vbe_set_palette(const struct paletteentry *entry, size_t slot)
{
        struct paletteentry pe;
        int mode, ret;

        if (!vbe_check() || (vbe->Capabilities & VBE_CAP_DAC8) == 0)
                return (1);

        if (gfx_fb.framebuffer_common.framebuffer_type !=
            MULTIBOOT_FRAMEBUFFER_TYPE_INDEXED) {
                return (1);
        }

        if (cmap == NULL)
                cmap = calloc(CMAP_SIZE, sizeof (*cmap));

        pe.Blue = entry->Blue;
        pe.Green = entry->Green;
        pe.Red = entry->Red;
        pe.Reserved = entry->Reserved;

        if (vbe->Capabilities & VBE_CAP_SNOW)
                mode = 0x80;
        else
                mode = 0;

        ret = biosvbe_palette_data(mode, slot, &pe);
        if (cmap != NULL && slot < CMAP_SIZE) {
                cmap[slot].mb_red = entry->Red;
                cmap[slot].mb_green = entry->Green;
                cmap[slot].mb_blue = entry->Blue;
        }

        return (ret == VBE_SUCCESS ? 0 : 1);
}

int
vbe_get_mode(void)
{
        return (vbestate.vbe_mode);
}

int
vbe_set_mode(int modenum)
{
        extern struct paletteentry *shadow_fb;
        struct modeinfoblock mi;
        int ret;

        if (!vbe_check())
                return (1);

        ret = biosvbe_get_mode_info(modenum, &mi);
        if (VBE_ERROR(ret)) {
                printf("mode 0x%x invalid\n", modenum);
                return (1);
        }

        if (!vbe_mode_is_supported(&mi)) {
                printf("mode 0x%x not supported\n", modenum);
                return (1);
        }

        /* calculate bytes per pixel */
        switch (mi.BitsPerPixel) {
        case 32:
        case 24:
        case 16:
        case 15:
        case 8:
                break;
        default:
                printf("BitsPerPixel %d is not supported\n", mi.BitsPerPixel);
                return (1);
        }

        ret = biosvbe_set_mode(modenum, NULL);
        if (VBE_ERROR(ret)) {
                printf("mode 0x%x could not be set\n", modenum);
                return (1);
        }

        /* make sure we have current MI in vbestate */
        memcpy(vbe_mode, &mi, sizeof (*vbe_mode));
        vbestate.vbe_mode = modenum;

        if (shadow_fb != NULL)
                free(shadow_fb);
        shadow_fb = malloc(mi.XResolution * mi.YResolution *
            sizeof (*shadow_fb));

        gfx_fb.framebuffer_common.framebuffer_addr =
            (uint64_t)mi.PhysBasePtr & 0xffffffff;
        gfx_fb.framebuffer_common.framebuffer_width = mi.XResolution;
        gfx_fb.framebuffer_common.framebuffer_height = mi.YResolution;
        gfx_fb.framebuffer_common.framebuffer_bpp = mi.BitsPerPixel;

        /* vbe_mode_is_supported() excludes the rest */
        switch (mi.MemoryModel) {
        case 0x4:
                gfx_fb.framebuffer_common.framebuffer_type =
                    MULTIBOOT_FRAMEBUFFER_TYPE_INDEXED;
                break;
        case 0x6:
                gfx_fb.framebuffer_common.framebuffer_type =
                    MULTIBOOT_FRAMEBUFFER_TYPE_RGB;
                break;
        }

        if (vbe->VbeVersion >= 0x300) {
                gfx_fb.framebuffer_common.framebuffer_pitch =
                    mi.LinBytesPerScanLine;
                gfx_fb.u.fb2.framebuffer_red_field_position =
                    mi.LinRedFieldPosition;
                gfx_fb.u.fb2.framebuffer_red_mask_size = mi.LinRedMaskSize;
                gfx_fb.u.fb2.framebuffer_green_field_position =
                    mi.LinGreenFieldPosition;
                gfx_fb.u.fb2.framebuffer_green_mask_size = mi.LinGreenMaskSize;
                gfx_fb.u.fb2.framebuffer_blue_field_position =
                    mi.LinBlueFieldPosition;
                gfx_fb.u.fb2.framebuffer_blue_mask_size = mi.LinBlueMaskSize;
        } else {
                gfx_fb.framebuffer_common.framebuffer_pitch =
                    mi.BytesPerScanLine;
                gfx_fb.u.fb2.framebuffer_red_field_position =
                    mi.RedFieldPosition;
                gfx_fb.u.fb2.framebuffer_red_mask_size = mi.RedMaskSize;
                gfx_fb.u.fb2.framebuffer_green_field_position =
                    mi.GreenFieldPosition;
                gfx_fb.u.fb2.framebuffer_green_mask_size = mi.GreenMaskSize;
                gfx_fb.u.fb2.framebuffer_blue_field_position =
                    mi.BlueFieldPosition;
                gfx_fb.u.fb2.framebuffer_blue_mask_size = mi.BlueMaskSize;
        }

        /*
         * Support for color mapping.
         * For 8, 24 and 32 bit depth, use mask size 8.
         * 15/16 bit depth needs to use mask size from mode, or we will
         * lose color information from 32-bit to 15/16 bit translation.
         */
        if (mi.BitsPerPixel == 15 || mi.BitsPerPixel == 16) {
                rgb_info.red.size = gfx_fb.u.fb2.framebuffer_red_mask_size;
                rgb_info.green.size = gfx_fb.u.fb2.framebuffer_green_mask_size;
                rgb_info.blue.size = gfx_fb.u.fb2.framebuffer_blue_mask_size;
        } else {
                rgb_info.red.size = 8;
                rgb_info.green.size = 8;
                rgb_info.blue.size = 8;
        }
        rgb_info.red.pos = 16;
        rgb_info.green.pos = 8;
        rgb_info.blue.pos = 0;

        return (0);
}

/*
 * Verify existance of mode number or find mode by
 * dimensions. If depth is not given, walk values 32, 24, 16, 8.
 */
static int
vbe_find_mode_xydm(int x, int y, int depth, int m)
{
        struct modeinfoblock mi;
        uint16_t mode;
        size_t idx, nentries;
        int i;

        memset(vbe, 0, sizeof (vbe));
        memcpy(vbe->VbeSignature, "VBE2", 4);
        if (biosvbe_info(vbe) != VBE_SUCCESS)
                return (0);
        if (memcmp(vbe->VbeSignature, "VESA", 4) != 0)
                return (0);

        if (m != -1)
                i = 8;
        else if (depth == -1)
                i = 32;
        else
                i = depth;

        nentries = vbe_mode_list_size / sizeof (*vbe_mode_list);
        while (i > 0) {
                for (idx = 0; idx < nentries; idx++) {
                        mode = vbe_mode_list[idx];
                        if (mode == VESA_END_OF_MODE_LIST)
                                break;

                        if (biosvbe_get_mode_info(mode, &mi) != VBE_SUCCESS)
                                continue;

                        /* we only care about linear modes here */
                        if (vbe_mode_is_supported(&mi) == 0)
                                continue;

                        if (m != -1) {
                                if (m == mode)
                                        return (mode);
                                else
                                        continue;
                        }

                        if (mi.XResolution == x &&
                            mi.YResolution == y &&
                            mi.BitsPerPixel == i)
                                return (mode);
                }
                if (depth != -1)
                        break;

                i -= 8;
        }

        return (0);
}

static int
vbe_find_mode(char *str)
{
        int x, y, depth;

        if (!gfx_parse_mode_str(str, &x, &y, &depth))
                return (0);

        return (vbe_find_mode_xydm(x, y, depth, -1));
}

static void
vbe_dump_mode(int modenum, struct modeinfoblock *mi)
{
        printf("0x%x=%dx%dx%d", modenum,
            mi->XResolution, mi->YResolution, mi->BitsPerPixel);
}

static bool
vbe_get_edid(edid_res_list_t *res)
{
        struct vesa_edid_info *edidp;
        const uint8_t magic[] = EDID_MAGIC;
        int ddc_caps;
        bool ret = false;

        if (edid_info != NULL)
                return (gfx_get_edid_resolution(edid_info, res));

        ddc_caps = biosvbe_ddc_caps();
        if (ddc_caps == 0) {
                return (ret);
        }

        edidp = bio_alloc(sizeof (*edidp));
        if (edidp == NULL)
                return (ret);
        memset(edidp, 0, sizeof (*edidp));

        if (VBE_ERROR(biosvbe_ddc_read_edid(0, edidp)))
                goto done;

        if (memcmp(edidp, magic, sizeof (magic)) != 0)
                goto done;

        /* Unknown EDID version. */
        if (edidp->header.version != 1)
                goto done;

        ret = gfx_get_edid_resolution(edidp, res);
        edid_info = malloc(sizeof (*edid_info));
        if (edid_info != NULL)
                memcpy(edid_info, edidp, sizeof (*edid_info));
done:
        bio_free(edidp, sizeof (*edidp));
        return (ret);
}

static bool
vbe_get_flatpanel(uint_t *pwidth, uint_t *pheight)
{
        struct flatpanelinfo *fp_info;
        bool ret = false;

        fp_info = bio_alloc(sizeof (*fp_info));
        if (fp_info == NULL)
                return (ret);
        memset(fp_info, 0, sizeof (*fp_info));

        if (VBE_ERROR(biosvbe_ddc_read_flat_panel_info(fp_info)))
                goto done;

        *pwidth = fp_info->HorizontalSize;
        *pheight = fp_info->VerticalSize;
        ret = true;

done:
        bio_free(fp_info, sizeof (*fp_info));
        return (ret);
}

static void
vbe_print_vbe_info(struct vbeinfoblock *vbep)
{
        char *oemstring = "";
        char *oemvendor = "", *oemproductname = "", *oemproductrev = "";

        if (vbep->OemStringPtr != 0)
                oemstring = vbe_farptr(vbep->OemStringPtr);

        if (vbep->OemVendorNamePtr != 0)
                oemvendor = vbe_farptr(vbep->OemVendorNamePtr);

        if (vbep->OemProductNamePtr != 0)
                oemproductname = vbe_farptr(vbep->OemProductNamePtr);

        if (vbep->OemProductRevPtr != 0)
                oemproductrev = vbe_farptr(vbep->OemProductRevPtr);

        printf("VESA VBE Version %d.%d\n%s\n", vbep->VbeVersion >> 8,
            vbep->VbeVersion & 0xF, oemstring);

        if (vbep->OemSoftwareRev != 0) {
                printf("OEM Version %d.%d, %s (%s, %s)\n",
                    vbep->OemSoftwareRev >> 8, vbep->OemSoftwareRev & 0xF,
                    oemvendor, oemproductname, oemproductrev);
        }
}

/* List available modes, filter by depth. If depth is -1, list all. */
void
vbe_modelist(int depth)
{
        struct modeinfoblock mi;
        uint16_t mode;
        int nmodes, idx, nentries;
        int ddc_caps;
        uint_t width, height;
        bool edid = false;
        edid_res_list_t res;
        struct resolution *rp;

        if (!vbe_check())
                return;

        ddc_caps = biosvbe_ddc_caps();
        if (ddc_caps & 3) {
                printf("DDC");
                if (ddc_caps & 1)
                        printf(" [DDC1]");
                if (ddc_caps & 2)
                        printf(" [DDC2]");

                TAILQ_INIT(&res);
                edid = vbe_get_edid(&res);
                if (edid) {
                        printf(": EDID");
                        while ((rp = TAILQ_FIRST(&res)) != NULL) {
                                printf(" %dx%d", rp->width, rp->height);
                                TAILQ_REMOVE(&res, rp, next);
                                free(rp);
                        }
                        printf("\n");
                } else {
                        printf(": no EDID information\n");
                }
        }
        if (!edid)
                if (vbe_get_flatpanel(&width, &height))
                        printf(": Panel %dx%d\n", width, height);

        nmodes = 0;
        memset(vbe, 0, sizeof (vbe));
        memcpy(vbe->VbeSignature, "VBE2", 4);
        if (biosvbe_info(vbe) != VBE_SUCCESS)
                goto done;
        if (memcmp(vbe->VbeSignature, "VESA", 4) != 0)
                goto done;

        vbe_print_vbe_info(vbe);
        printf("Modes: ");

        nentries = vbe_mode_list_size / sizeof (*vbe_mode_list);
        for (idx = 0; idx < nentries; idx++) {
                mode = vbe_mode_list[idx];
                if (mode == VESA_END_OF_MODE_LIST)
                        break;

                if (biosvbe_get_mode_info(mode, &mi) != VBE_SUCCESS)
                        continue;

                /* we only care about linear modes here */
                if (vbe_mode_is_supported(&mi) == 0)
                        continue;

                /* apply requested filter */
                if (depth != -1 && mi.BitsPerPixel != depth)
                        continue;

                if (nmodes % 4 == 0)
                        printf("\n");
                else
                        printf("  ");

                vbe_dump_mode(mode, &mi);
                nmodes++;
        }

done:
        if (nmodes == 0)
                printf("none found");
        printf("\n");
}

static void
vbe_print_mode(bool verbose)
{
        int nc, mode, i, rc;

        if (verbose)
                nc = 256;
        else
                nc = 16;

        memset(vbe, 0, sizeof (vbe));
        memcpy(vbe->VbeSignature, "VBE2", 4);
        if (biosvbe_info(vbe) != VBE_SUCCESS)
                return;

        if (memcmp(vbe->VbeSignature, "VESA", 4) != 0)
                return;

        vbe_print_vbe_info(vbe);

        if (biosvbe_get_mode(&mode) != VBE_SUCCESS) {
                printf("Error getting current VBE mode\n");
                return;
        }

        if (biosvbe_get_mode_info(mode, vbe_mode) != VBE_SUCCESS ||
            vbe_mode_is_supported(vbe_mode) == 0) {
                printf("VBE mode (0x%x) is not framebuffer mode\n", mode);
                return;
        }

        printf("\nCurrent VBE mode: ");
        vbe_dump_mode(mode, vbe_mode);
        printf("\n");

        printf("%ux%ux%u, stride=%u\n",
            gfx_fb.framebuffer_common.framebuffer_width,
            gfx_fb.framebuffer_common.framebuffer_height,
            gfx_fb.framebuffer_common.framebuffer_bpp,
            (gfx_fb.framebuffer_common.framebuffer_pitch << 3) /
            gfx_fb.framebuffer_common.framebuffer_bpp);
        printf("    frame buffer: address=%jx, size=%jx\n",
            (uintmax_t)gfx_fb.framebuffer_common.framebuffer_addr,
            (uintmax_t)gfx_fb.framebuffer_common.framebuffer_height *
            gfx_fb.framebuffer_common.framebuffer_pitch);

        if (vbe_mode->MemoryModel == 0x6) {
                printf("    color mask: R=%08x, G=%08x, B=%08x\n",
                    ((1 << gfx_fb.u.fb2.framebuffer_red_mask_size) - 1) <<
                    gfx_fb.u.fb2.framebuffer_red_field_position,
                    ((1 << gfx_fb.u.fb2.framebuffer_green_mask_size) - 1) <<
                    gfx_fb.u.fb2.framebuffer_green_field_position,
                    ((1 << gfx_fb.u.fb2.framebuffer_blue_mask_size) - 1) <<
                    gfx_fb.u.fb2.framebuffer_blue_field_position);
                return;
        }

        mode = 1;       /* get DAC palette width */
        rc = biosvbe_palette_format(&mode);
        if (rc != VBE_SUCCESS)
                return;

        printf("    palette format: %x bits per primary\n", mode);
        if (cmap == NULL)
                return;

        pager_open();
        for (i = 0; i < nc; i++) {
                printf("%d: R=%02x, G=%02x, B=%02x", i,
                    cmap[i].mb_red, cmap[i].mb_green, cmap[i].mb_blue);
                if (pager_output("\n") != 0)
                        break;
        }
        pager_close();
}

/*
 * Try EDID preferred mode, if EDID or the suggested mode is not available,
 * then try flat panel information.
 * Fall back to VBE_DEFAULT_MODE.
 */
int
vbe_default_mode(void)
{
        edid_res_list_t res;
        struct resolution *rp;
        int modenum;
        uint_t width, height;

        modenum = 0;
        TAILQ_INIT(&res);
        if (vbe_get_edid(&res)) {
                while ((rp = TAILQ_FIRST(&res)) != NULL) {
                        if (modenum == 0) {
                                modenum = vbe_find_mode_xydm(
                                    rp->width, rp->height, -1, -1);
                        }
                        TAILQ_REMOVE(&res, rp, next);
                        free(rp);
                }
        }

        if (modenum == 0 &&
            vbe_get_flatpanel(&width, &height)) {
                modenum = vbe_find_mode_xydm(width, height, -1, -1);
        }

        /* Still no mode? Fall back to default. */
        if (modenum == 0)
                modenum = vbe_find_mode(VBE_DEFAULT_MODE);
        return (modenum);
}

COMMAND_SET(framebuffer, "framebuffer", "framebuffer mode management",
    command_vesa);

int
command_vesa(int argc, char *argv[])
{
        char *arg, *cp;
        int modenum = -1, n;

        if (!vbe_check())
                return (CMD_OK);

        if (argc < 2)
                goto usage;

        if (strcmp(argv[1], "list") == 0) {
                n = -1;
                if (argc != 2 && argc != 3)
                        goto usage;

                if (argc == 3) {
                        arg = argv[2];
                        errno = 0;
                        n = strtoul(arg, &cp, 0);
                        if (errno != 0 || *arg == '\0' || cp[0] != '\0') {
                                snprintf(command_errbuf,
                                    sizeof (command_errbuf),
                                    "depth should be an integer");
                                return (CMD_ERROR);
                        }
                }
                vbe_modelist(n);
                return (CMD_OK);
        }

        if (strcmp(argv[1], "get") == 0) {
                bool verbose = false;

                if (argc > 2) {
                        if (argc > 3 || strcmp(argv[2], "-v") != 0)
                                goto usage;
                        verbose = true;
                }

                vbe_print_mode(verbose);
                return (CMD_OK);
        }

        if (strcmp(argv[1], "off") == 0) {
                if (argc != 2)
                        goto usage;

                if (vbestate.vbe_mode == 0)
                        return (CMD_OK);

                reset_font_flags();
                bios_text_font(true);
                bios_set_text_mode(VGA_TEXT_MODE);
                plat_cons_update_mode(0);
                return (CMD_OK);
        }

        if (strcmp(argv[1], "on") == 0) {
                if (argc != 2)
                        goto usage;

                modenum = vbe_default_mode();
                if (modenum == 0) {
                        snprintf(command_errbuf, sizeof (command_errbuf),
                            "%s: no suitable VBE mode number found", argv[0]);
                        return (CMD_ERROR);
                }
        } else if (strcmp(argv[1], "set") == 0) {
                if (argc != 3)
                        goto usage;

                if (strncmp(argv[2], "0x", 2) == 0) {
                        arg = argv[2];
                        errno = 0;
                        n = strtoul(arg, &cp, 0);
                        if (errno != 0 || *arg == '\0' || cp[0] != '\0') {
                                snprintf(command_errbuf,
                                    sizeof (command_errbuf),
                                    "mode should be an integer");
                                return (CMD_ERROR);
                        }
                        modenum = vbe_find_mode_xydm(0, 0, 0, n);
                } else if (strchr(argv[2], 'x') != NULL) {
                        modenum = vbe_find_mode(argv[2]);
                }
        } else {
                goto usage;
        }

        if (modenum == 0) {
                snprintf(command_errbuf, sizeof (command_errbuf),
                    "%s: mode %s not supported by firmware\n",
                    argv[0], argv[2]);
                return (CMD_ERROR);
        }

        if (modenum >= VESA_MODE_BASE) {
                if (vbestate.vbe_mode != modenum) {
                        reset_font_flags();
                        bios_text_font(false);
                        vbe_set_mode(modenum);
                        plat_cons_update_mode(1);
                }
                return (CMD_OK);
        } else {
                snprintf(command_errbuf, sizeof (command_errbuf),
                    "%s: mode %s is not framebuffer mode\n", argv[0], argv[2]);
                return (CMD_ERROR);
        }

usage:
        snprintf(command_errbuf, sizeof (command_errbuf),
            "usage: %s on | off | get [-v] | list [depth] | "
            "set <display or VBE mode number>", argv[0]);
        return (CMD_ERROR);
}