/*
 *  Copyright (c) 2004-2005 Fabrice Bellard
 *
 *   This program is free software; you can redistribute it and/or
 *   modify it under the terms of the GNU General Public License V2
 *   as published by the Free Software Foundation
 *
 *   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., 51 Franklin St, Fifth Floor, Boston,
 *   MA 02110-1301, USA.
 */

#include "openbios/config.h"
#include "openbios/kernel.h"
#include "openbios/bindings.h"
#include "openbios/pci.h"
#include "openbios/drivers.h"
#include "asm/io.h"
#include "video_subr.h"

/* VGA init. We use the Bochs VESA VBE extensions  */
#define VBE_DISPI_INDEX_ID              0x0
#define VBE_DISPI_INDEX_XRES            0x1
#define VBE_DISPI_INDEX_YRES            0x2
#define VBE_DISPI_INDEX_BPP             0x3
#define VBE_DISPI_INDEX_ENABLE          0x4
#define VBE_DISPI_INDEX_BANK            0x5
#define VBE_DISPI_INDEX_VIRT_WIDTH      0x6
#define VBE_DISPI_INDEX_VIRT_HEIGHT     0x7
#define VBE_DISPI_INDEX_X_OFFSET        0x8
#define VBE_DISPI_INDEX_Y_OFFSET        0x9
#define VBE_DISPI_INDEX_NB              0xa

#define VBE_DISPI_ID0                   0xB0C0
#define VBE_DISPI_ID1                   0xB0C1
#define VBE_DISPI_ID2                   0xB0C2

#define VBE_DISPI_DISABLED              0x00
#define VBE_DISPI_ENABLED               0x01
#define VBE_DISPI_LFB_ENABLED           0x40
#define VBE_DISPI_NOCLEARMEM            0x80

static void vbe_outw(int index, int val)
{
    outw(index, 0x1ce);
    outw(val, 0x1d0);
}

/* for depth = 8 mode, set a hardware palette entry */
void vga_set_color(int i, unsigned int r, unsigned int g, unsigned int b)
{
    r &= 0xff;
    g &= 0xff;
    b &= 0xff;
    outb(i, 0x3c8);
    outb(r >> 2, 0x3c9);
    outb(g >> 2, 0x3c9);
    outb(b >> 2, 0x3c9);
}

/* build standard RGB palette */
static void vga_build_rgb_palette(void)
{
    static const uint8_t pal_value[6] = { 0x00, 0x33, 0x66, 0x99, 0xcc, 0xff };
    int i, r, g, b;

    i = 0;
    for(r = 0; r < 6; r++) {
        for(g = 0; g < 6; g++) {
            for(b = 0; b < 6; b++) {
                vga_set_color(i, pal_value[r], pal_value[g], pal_value[b]);
                i++;
            }
        }
    }
}

/* depth = 8, 15, 16 or 32 */
void vga_vbe_set_mode(int width, int height, int depth)
{
    outb(0x00, 0x3c0); /* enable blanking */
    vbe_outw(VBE_DISPI_INDEX_ENABLE, VBE_DISPI_DISABLED);
    vbe_outw(VBE_DISPI_INDEX_X_OFFSET, 0);
    vbe_outw(VBE_DISPI_INDEX_Y_OFFSET, 0);
    vbe_outw(VBE_DISPI_INDEX_XRES, width);
    vbe_outw(VBE_DISPI_INDEX_YRES, height);
    vbe_outw(VBE_DISPI_INDEX_BPP, depth);
    vbe_outw(VBE_DISPI_INDEX_ENABLE, VBE_DISPI_ENABLED);
    outb(0x00, 0x3c0);
    outb(0x20, 0x3c0); /* disable blanking */

    if (depth == 8)
        vga_build_rgb_palette();
}

void vga_vbe_init(const char *path, uint32_t fb, uint32_t fb_size,
                  unsigned long rom, uint32_t rom_size)
{
	phandle_t ph, chosen, aliases;

	vga_vbe_set_mode(800, 600, 8);

	ph = find_dev(path);

	set_int_property(ph, "width", 800);
	set_int_property(ph, "height", 600);
	set_int_property(ph, "depth", 8);
	set_int_property(ph, "linebytes", 800);
	set_int_property(ph, "address", fb & ~0x0000000F);

	chosen = find_dev("/chosen");
	push_str(path);
	fword("open-dev");
	set_int_property(chosen, "display", POP());

	aliases = find_dev("/aliases");
	set_property(aliases, "screen", path, strlen(path) + 1);

	if (rom_size >= 8) {
                const char *p;
		int size;

                p = (const char *)rom;
		if (p[0] == 'N' && p[1] == 'D' && p[2] == 'R' && p[3] == 'V') {
			size = *(uint32_t*)(p + 4);
			set_property(ph, "driver,AAPL,MacOS,PowerPC",
				     p + 8, size);
		}
	}

	init_video(fb, 800, 600, 8, 800);
}