/*
 * Copyright © 2006 Intel Corporation
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 *
 * Authors:
 *    Eric Anholt <eric@anholt.net>
 *
 */
#ifdef HAVE_CONFIG_H
#include "config.h"
#undef VERSION	/* XXX edid.h has a VERSION too */
#endif

#include <stdio.h>
#include <string.h>

#define _PARSE_EDID_
#include "xf86.h"
#include "i830.h"
#include "i830_bios.h"
#include "edid.h"

#define INTEL_BIOS_8(_addr)	(pI830->VBIOS[_addr])
#define INTEL_BIOS_16(_addr)	(pI830->VBIOS[_addr] | \
				 (pI830->VBIOS[_addr + 1] << 8))
#define INTEL_BIOS_32(_addr)	(pI830->VBIOS[_addr] | \
				 (pI830->VBIOS[_addr + 1] << 8) \
				 (pI830->VBIOS[_addr + 2] << 16) \
				 (pI830->VBIOS[_addr + 3] << 24))

/* XXX */
#define INTEL_VBIOS_SIZE (64 * 1024)

static void
i830DumpBIOSToFile(ScrnInfoPtr pScrn)
{
    I830Ptr pI830 = I830PTR(pScrn);
    const char *filename = "/tmp/xf86-video-intel-VBIOS";
    FILE *f;

    f = fopen(filename, "w");
    if (f == NULL) {
	xf86DrvMsg(pScrn->scrnIndex, X_ERROR, "Couldn't open %s\n", filename);
	return;
    }
    if (fwrite(pI830->VBIOS, INTEL_VBIOS_SIZE, 1, f) != 1) {
	xf86DrvMsg(pScrn->scrnIndex, X_ERROR, "Couldn't write BIOS data\n");
    }

    xf86DrvMsg(pScrn->scrnIndex, X_INFO, "Wrote BIOS contents to %s\n",
	       filename);
    fclose(f);
}

/**
 * Loads the Video BIOS and checks that the VBT exists.
 *
 * VBT existence is a sanity check that is relied on by other i830_bios.c code.
 * Note that it would be better to use a BIOS call to get the VBT, as BIOSes may
 * feed an updated VBT back through that, compared to what we'll fetch using
 * this method of groping around in the BIOS data.
 */
static Bool
i830GetBIOS(ScrnInfoPtr pScrn)
{
    I830Ptr pI830 = I830PTR(pScrn);
    struct vbt_header *vbt;
    int vbt_off;

    if (pI830->VBIOS != NULL)
	return TRUE;

    pI830->VBIOS = xalloc(INTEL_VBIOS_SIZE);
    if (pI830->VBIOS == NULL)
	return FALSE;

    if (pI830->pVbe != NULL) {
	memcpy(pI830->VBIOS, xf86int10Addr(pI830->pVbe->pInt10,
					   pI830->pVbe->pInt10->BIOSseg << 4),
	       INTEL_VBIOS_SIZE);
    } else {
	xf86ReadPciBIOS(0, pI830->PciTag, 0, pI830->VBIOS, INTEL_VBIOS_SIZE);
    }

    if (0)
	i830DumpBIOSToFile(pScrn);

    vbt_off = INTEL_BIOS_16(0x1a);
    if (vbt_off >= INTEL_VBIOS_SIZE) {
	xf86DrvMsg(pScrn->scrnIndex, X_ERROR, "Bad VBT offset: 0x%x\n",
		   vbt_off);
	xfree(pI830->VBIOS);
	return FALSE;
    }

    vbt = (struct vbt_header *)(pI830->VBIOS + vbt_off);

    if (memcmp(vbt->signature, "$VBT", 4) != 0) {
	xf86DrvMsg(pScrn->scrnIndex, X_ERROR, "Bad VBT signature\n");
	xfree(pI830->VBIOS);
	return FALSE;
    }

    return TRUE;
}

Bool
i830GetLVDSInfoFromBIOS(ScrnInfoPtr pScrn)
{
    I830Ptr pI830 = I830PTR(pScrn);
    struct vbt_header *vbt;
    struct bdb_header *bdb;
    int vbt_off, bdb_off, bdb_block_off, block_size;
    int panel_type = -1;
    Bool found_panel_info = FALSE;

    if (!i830GetBIOS(pScrn))
	return FALSE;

    vbt_off = INTEL_BIOS_16(0x1a);
    vbt = (struct vbt_header *)(pI830->VBIOS + vbt_off);
    bdb_off = vbt_off + vbt->bdb_offset;
    bdb = (struct bdb_header *)(pI830->VBIOS + bdb_off);

    if (memcmp(bdb->signature, "BIOS_DATA_BLOCK ", 16) != 0) {
	xf86DrvMsg(pScrn->scrnIndex, X_ERROR, "Bad BDB signature\n");
	return FALSE;
    }

    for (bdb_block_off = bdb->header_size; bdb_block_off < bdb->bdb_size;
	 bdb_block_off += block_size)
    {
	int start = bdb_off + bdb_block_off;
	int id;
	struct lvds_bdb_1 *lvds1;
	struct lvds_bdb_2 *lvds2;
	struct lvds_bdb_2_fp_params *fpparam;
	struct lvds_bdb_2_fp_edid_dtd *fptiming;
	CARD8 *timing_ptr;

	id = INTEL_BIOS_8(start);
	block_size = INTEL_BIOS_16(start + 1) + 3;
	xf86DrvMsg(pScrn->scrnIndex, X_INFO, "Found BDB block type %d\n", id);
	switch (id) {
	case 40:
	    lvds1 = (struct lvds_bdb_1 *)(pI830->VBIOS + start);
	    panel_type = lvds1->panel_type;
	    if (lvds1->caps & LVDS_CAP_DITHER)
		pI830->panel_wants_dither = TRUE;
	    break;
	case 41:
	    if (panel_type == -1)
		break;

	    lvds2 = (struct lvds_bdb_2 *)(pI830->VBIOS + start);
	    fpparam = (struct lvds_bdb_2_fp_params *)(pI830->VBIOS +
		bdb_off + lvds2->panels[panel_type].fp_params_offset);
	    fptiming = (struct lvds_bdb_2_fp_edid_dtd *)(pI830->VBIOS +
		bdb_off + lvds2->panels[panel_type].fp_edid_dtd_offset);
	    timing_ptr = pI830->VBIOS + bdb_off +
	        lvds2->panels[panel_type].fp_edid_dtd_offset;

	    if (fpparam->terminator != 0xffff) {
		/* Apparently the offsets are wrong for some BIOSes, so we
		 * try the other offsets if we find a bad terminator.
		 */
		fpparam = (struct lvds_bdb_2_fp_params *)(pI830->VBIOS +
		    bdb_off + lvds2->panels[panel_type].fp_params_offset + 8);
		fptiming = (struct lvds_bdb_2_fp_edid_dtd *)(pI830->VBIOS +
		    bdb_off + lvds2->panels[panel_type].fp_edid_dtd_offset + 8);
		timing_ptr = pI830->VBIOS + bdb_off +
	            lvds2->panels[panel_type].fp_edid_dtd_offset + 8;

		if (fpparam->terminator != 0xffff)
		    continue;
	    }

	    pI830->PanelXRes = fpparam->x_res;
	    pI830->PanelYRes = fpparam->y_res;
	    xf86DrvMsg(pScrn->scrnIndex, X_INFO,
		       "Found panel of size %dx%d in BIOS VBT tables\n",
		       pI830->PanelXRes, pI830->PanelYRes);

	    /* Since lvds_bdb_2_fp_edid_dtd is just an EDID detailed timing
	     * block, pull the contents out using EDID macros.
	     */
	    pI830->panel_fixed_clock = _PIXEL_CLOCK(timing_ptr) / 1000;
	    pI830->panel_fixed_hactive = _H_ACTIVE(timing_ptr);
	    pI830->panel_fixed_hblank = _H_BLANK(timing_ptr);
	    pI830->panel_fixed_hsyncoff = _H_SYNC_OFF(timing_ptr);
	    pI830->panel_fixed_hsyncwidth = _H_SYNC_WIDTH(timing_ptr);

	    pI830->panel_fixed_vactive = _V_ACTIVE(timing_ptr);
	    pI830->panel_fixed_vblank = _V_BLANK(timing_ptr);
	    pI830->panel_fixed_vsyncoff = _V_SYNC_OFF(timing_ptr);
	    pI830->panel_fixed_vsyncwidth = _V_SYNC_WIDTH(timing_ptr);

	    found_panel_info = TRUE;
	    break;
	}
    }

    return found_panel_info;
}