/*
 * This file is part of the coreboot project.
 *
 * Copyright 2013 Google Inc.
 *
 * 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; version 2 of the License.
 *
 * 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.
 */

#include <types.h>
#include <string.h>
#include <stdlib.h>
#include <device/device.h>
#include <device/device.h>
#include <device/pci_def.h>
#include <device/pci_ops.h>
#include <console/console.h>
#include <delay.h>
#include <pc80/mc146818rtc.h>
#include <arch/acpi.h>
#include <arch/io.h>
#include <arch/interrupt.h>
#include <boot/coreboot_tables.h>
#include <smbios.h>
#include <device/pci.h>
#include <ec/google/chromeec/ec.h>

#include <cpu/x86/tsc.h>
#include <cpu/x86/cache.h>
#include <cpu/x86/mtrr.h>
#include <cpu/x86/msr.h>
#include <edid.h>
#include <drivers/intel/gma/i915.h>
#include <northbridge/intel/haswell/haswell.h>
#include "mainboard.h"

/*
 * Here is the rough outline of how we bring up the display:
 *  1. Upon power-on Sink generates a hot plug detection pulse thru HPD
 *  2. Source determines video mode by reading DPCD receiver capability field
 *     (DPCD 00000h to 0000Dh) including eDP CP capability register (DPCD
 *     0000Dh).
 *  3. Sink replies DPCD receiver capability field.
 *  4. Source starts EDID read thru I2C-over-AUX.
 *  5. Sink replies EDID thru I2C-over-AUX.
 *  6. Source determines link configuration, such as MAX_LINK_RATE and
 *     MAX_LANE_COUNT. Source also determines which type of eDP Authentication
 *     method to use and writes DPCD link configuration field (DPCD 00100h to
 *     0010Ah) including eDP configuration set (DPCD 0010Ah).
 *  7. Source starts link training. Sink does clock recovery and equalization.
 *  8. Source reads DPCD link status field (DPCD 00200h to 0020Bh).
 *  9. Sink replies DPCD link status field. If main link is not stable, Source
 *     repeats Step 7.
 * 10. Source sends MSA (Main Stream Attribute) data. Sink extracts video
 *     parameters and recovers stream clock.
 * 11. Source sends video data.
 */

/* how many bytes do we need for the framebuffer?
 * Well, this gets messy. To get an exact answer, we have
 * to ask the panel, but we'd rather zero the memory
 * and set up the gtt while the panel powers up. So,
 * we take a reasonable guess, secure in the knowledge that the
 * MRC has to overestimate the number of bytes used.
 * 8 MiB is a very safe guess. There may be a better way later, but
 * fact is, the initial framebuffer is only very temporary. And taking
 * a little long is ok; this is done much faster than the AUX
 * channel is ready for IO.
 */
#define FRAME_BUFFER_BYTES (8*MiB)
/* how many 4096-byte pages do we need for the framebuffer?
 * There are hard ways to get this, and easy ways:
 * there are FRAME_BUFFER_BYTES/4096 pages, since pages are 4096
 * on this chip (and in fact every Intel graphics chip we've seen).
 */
#define FRAME_BUFFER_PAGES (FRAME_BUFFER_BYTES/(4096))

static int i915_init_done = 0;

/* fill the palette. */
static void palette(void)
{
	int i;
	unsigned long color = 0;

	for(i = 0; i < 256; i++, color += 0x010101){
		gtt_write(_LGC_PALETTE_A + (i << 2),color);
	}
}

void mainboard_train_link(struct intel_dp *intel_dp)
{
	u8 read_val;
	u8 link_status[DP_LINK_STATUS_SIZE];

	gtt_write(DP_TP_CTL(intel_dp->port),DP_TP_CTL_ENABLE | DP_TP_CTL_ENHANCED_FRAME_ENABLE);
	gtt_write(DP_A, DP_PORT_EN | DP_LINK_TRAIN_PAT_1 | DP_LINK_TRAIN_PAT_1_CPT | DP_VOLTAGE_0_4 | DP_PRE_EMPHASIS_0 | DP_PORT_WIDTH_1 | DP_PLL_FREQ_270MHZ | DP_SYNC_VS_HIGH |0x80000011);

	intel_dp_get_training_pattern(intel_dp, &read_val);
	intel_dp_set_training_pattern(intel_dp, DP_TRAINING_PATTERN_1 | DP_LINK_QUAL_PATTERN_DISABLE | DP_SYMBOL_ERROR_COUNT_BOTH);
	intel_dp_get_lane_count(intel_dp, &read_val);
	intel_dp_set_training_lane0(intel_dp, DP_TRAIN_VOLTAGE_SWING_400 | DP_TRAIN_PRE_EMPHASIS_0);
	intel_dp_get_link_status(intel_dp, link_status);

	gtt_write(DP_TP_CTL(intel_dp->port),DP_TP_CTL_ENABLE | DP_TP_CTL_ENHANCED_FRAME_ENABLE | DP_TP_CTL_LINK_TRAIN_PAT2);

	intel_dp_get_training_pattern(intel_dp, &read_val);
	intel_dp_set_training_pattern(intel_dp, DP_TRAINING_PATTERN_2 | DP_LINK_QUAL_PATTERN_DISABLE | DP_SYMBOL_ERROR_COUNT_BOTH);
	intel_dp_get_link_status(intel_dp, link_status);
	intel_dp_get_lane_align_status(intel_dp, &read_val);
	intel_dp_get_training_pattern(intel_dp, &read_val);
	intel_dp_set_training_pattern(intel_dp, DP_TRAINING_PATTERN_DISABLE | DP_LINK_QUAL_PATTERN_DISABLE | DP_SYMBOL_ERROR_COUNT_BOTH);
}

#define TEST_GFX 0

#if TEST_GFX
static void test_gfx(struct intel_dp *dp)
{
	int i;

	/* This is a sanity test code which fills the screen with two bands --
	   green and blue. It is very useful to ensure all the initializations
	   are made right. Thus, to be used only for testing, not otherwise
	*/
	for (i = 0; i < (dp->edid.va - 4); i++) {
		u32 *l;
		int j;
		u32 tcolor = 0x0ff;
		for (j = 0; j < (dp->edid.ha-4); j++) {
			if (j == (dp->edid.ha/2)) {
				tcolor = 0xff00;
			}
			l = (u32*)(graphics + i * dp->stride + j * sizeof(tcolor));
			memcpy(l,&tcolor,sizeof(tcolor));
		}
	}
}
#else
static void test_gfx(struct intel_dp *dp) {}
#endif


void mainboard_set_port_clk_dp(struct intel_dp *intel_dp)
{
	u32 ddi_pll_sel = 0;

	switch (intel_dp->link_bw) {
	case DP_LINK_BW_1_62:
		ddi_pll_sel = PORT_CLK_SEL_LCPLL_810;
		break;
	case DP_LINK_BW_2_7:
		ddi_pll_sel = PORT_CLK_SEL_LCPLL_1350;
		break;
	case DP_LINK_BW_5_4:
		ddi_pll_sel = PORT_CLK_SEL_LCPLL_2700;
		break;
	default:
		printk(BIOS_ERR, "invalid link bw %d\n", intel_dp->link_bw);
		return;
	}

	gtt_write(PORT_CLK_SEL(intel_dp->port), ddi_pll_sel);
}

int panel_lightup(struct intel_dp *dp, unsigned int init_fb)
{
	int i;
	int edid_ok;
	int pixels = FRAME_BUFFER_BYTES/64;

	void runio(struct intel_dp *dp);

	dp->gen = 8; // This is gen 8 which we believe is Haswell
	dp->is_haswell = 1;
	dp->DP = 0x2;
	/* These values are used for training the link */
	dp->lane_count = 2;
	dp->link_bw = DP_LINK_BW_2_7;
	dp->pipe = PIPE_A;
	dp->port = PORT_A;
	dp->plane = PLANE_A;
	dp->clock = 160000;
	dp->pipe_bits_per_pixel = 32;
	dp->type = INTEL_OUTPUT_EDP;
	dp->output_reg = DP_A;
	/* observed from YABEL. */
	dp->aux_clock_divider = 0xe1;
	dp->precharge = 3;

	/* 1. Normal mode: Set the first page to zero and make
	   all GTT entries point to the same page
	   2. Developer/Recovery mode: We do not zero out all
	   the pages pointed to by GTT in order to avoid wasting time */
        if (init_fb){
		set_translation_table(0, FRAME_BUFFER_PAGES, dp->physbase, 4096);
		memset((void *)dp->graphics, 0x55, FRAME_BUFFER_PAGES*4096);
        } else {
                set_translation_table(0, FRAME_BUFFER_PAGES, dp->physbase, 0);
                memset((void*)dp->graphics, 0, 4096);
        }

	dp->address = 0x50;

	if ( !intel_dp_get_dpcd(dp) )
		goto fail;

	intel_dp_i2c_aux_ch(dp, MODE_I2C_WRITE, 0, NULL);
	for(dp->edidlen = i = 0; i < sizeof(dp->rawedid); i++){
		if (intel_dp_i2c_aux_ch(dp, MODE_I2C_READ,
					0x50, &dp->rawedid[i]) < 0)
			break;
		dp->edidlen++;
	}

	edid_ok = decode_edid(dp->rawedid, dp->edidlen, &dp->edid);
	printk(BIOS_SPEW, "decode edid returns %d\n", edid_ok);

	compute_display_params(dp);

	intel_ddi_set_pipe_settings(dp);

	runio(dp);

	palette();

	pixels = dp->edid.mode.ha * (dp->edid.mode.va-4) * 4;
	printk(BIOS_SPEW, "ha=%d, va=%d\n",dp->edid.mode.ha, dp->edid.mode.va);

	test_gfx(dp);

	set_vbe_mode_info_valid(&dp->edid, (uintptr_t)dp->graphics);
	i915_init_done = 1;
	return i915_init_done;

fail:
	printk(BIOS_SPEW, "Graphics could not be started;");
	printk(BIOS_SPEW, "Returning.\n");
	return 0;
}