/*
 * Copyright (c) 2015, The Linux Foundation. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 and
 * only version 2 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.
 */

#include <drm/drm_crtc.h>
#include <drm/drm_crtc_helper.h>

#include "mdp5_kms.h"

static struct mdp5_kms *get_kms(struct drm_encoder *encoder)
{
	struct msm_drm_private *priv = encoder->dev->dev_private;
	return to_mdp5_kms(to_mdp_kms(priv->kms));
}

#ifdef DOWNSTREAM_CONFIG_MSM_BUS_SCALING
#include <mach/board.h>
#include <linux/msm-bus.h>
#include <linux/msm-bus-board.h>

static void bs_set(struct mdp5_encoder *mdp5_cmd_enc, int idx)
{
	if (mdp5_cmd_enc->bsc) {
		DBG("set bus scaling: %d", idx);
		/* HACK: scaling down, and then immediately back up
		 * seems to leave things broken (underflow).. so
		 * never disable:
		 */
		idx = 1;
		msm_bus_scale_client_update_request(mdp5_cmd_enc->bsc, idx);
	}
}
#else
static void bs_set(struct mdp5_encoder *mdp5_cmd_enc, int idx) {}
#endif

#define VSYNC_CLK_RATE 19200000
static int pingpong_tearcheck_setup(struct drm_encoder *encoder,
				    struct drm_display_mode *mode)
{
	struct mdp5_kms *mdp5_kms = get_kms(encoder);
	struct device *dev = encoder->dev->dev;
	u32 total_lines_x100, vclks_line, cfg;
	long vsync_clk_speed;
	struct mdp5_hw_mixer *mixer = mdp5_crtc_get_mixer(encoder->crtc);
	int pp_id = mixer->pp;

	if (IS_ERR_OR_NULL(mdp5_kms->vsync_clk)) {
		dev_err(dev, "vsync_clk is not initialized\n");
		return -EINVAL;
	}

	total_lines_x100 = mode->vtotal * mode->vrefresh;
	if (!total_lines_x100) {
		dev_err(dev, "%s: vtotal(%d) or vrefresh(%d) is 0\n",
				__func__, mode->vtotal, mode->vrefresh);
		return -EINVAL;
	}

	vsync_clk_speed = clk_round_rate(mdp5_kms->vsync_clk, VSYNC_CLK_RATE);
	if (vsync_clk_speed <= 0) {
		dev_err(dev, "vsync_clk round rate failed %ld\n",
							vsync_clk_speed);
		return -EINVAL;
	}
	vclks_line = vsync_clk_speed * 100 / total_lines_x100;

	cfg = MDP5_PP_SYNC_CONFIG_VSYNC_COUNTER_EN
		| MDP5_PP_SYNC_CONFIG_VSYNC_IN_EN;
	cfg |= MDP5_PP_SYNC_CONFIG_VSYNC_COUNT(vclks_line);

	/*
	 * Tearcheck emits a blanking signal every vclks_line * vtotal * 2 ticks on
	 * the vsync_clk equating to roughly half the desired panel refresh rate.
	 * This is only necessary as stability fallback if interrupts from the
	 * panel arrive too late or not at all, but is currently used by default
	 * because these panel interrupts are not wired up yet.
	 */
	mdp5_write(mdp5_kms, REG_MDP5_PP_SYNC_CONFIG_VSYNC(pp_id), cfg);
	mdp5_write(mdp5_kms,
		REG_MDP5_PP_SYNC_CONFIG_HEIGHT(pp_id), (2 * mode->vtotal));

	mdp5_write(mdp5_kms,
		REG_MDP5_PP_VSYNC_INIT_VAL(pp_id), mode->vdisplay);
	mdp5_write(mdp5_kms, REG_MDP5_PP_RD_PTR_IRQ(pp_id), mode->vdisplay + 1);
	mdp5_write(mdp5_kms, REG_MDP5_PP_START_POS(pp_id), mode->vdisplay);
	mdp5_write(mdp5_kms, REG_MDP5_PP_SYNC_THRESH(pp_id),
			MDP5_PP_SYNC_THRESH_START(4) |
			MDP5_PP_SYNC_THRESH_CONTINUE(4));

	return 0;
}

static int pingpong_tearcheck_enable(struct drm_encoder *encoder)
{
	struct mdp5_kms *mdp5_kms = get_kms(encoder);
	struct mdp5_hw_mixer *mixer = mdp5_crtc_get_mixer(encoder->crtc);
	int pp_id = mixer->pp;
	int ret;

	ret = clk_set_rate(mdp5_kms->vsync_clk,
		clk_round_rate(mdp5_kms->vsync_clk, VSYNC_CLK_RATE));
	if (ret) {
		dev_err(encoder->dev->dev,
			"vsync_clk clk_set_rate failed, %d\n", ret);
		return ret;
	}
	ret = clk_prepare_enable(mdp5_kms->vsync_clk);
	if (ret) {
		dev_err(encoder->dev->dev,
			"vsync_clk clk_prepare_enable failed, %d\n", ret);
		return ret;
	}

	mdp5_write(mdp5_kms, REG_MDP5_PP_TEAR_CHECK_EN(pp_id), 1);

	return 0;
}

static void pingpong_tearcheck_disable(struct drm_encoder *encoder)
{
	struct mdp5_kms *mdp5_kms = get_kms(encoder);
	struct mdp5_hw_mixer *mixer = mdp5_crtc_get_mixer(encoder->crtc);
	int pp_id = mixer->pp;

	mdp5_write(mdp5_kms, REG_MDP5_PP_TEAR_CHECK_EN(pp_id), 0);
	clk_disable_unprepare(mdp5_kms->vsync_clk);
}

void mdp5_cmd_encoder_mode_set(struct drm_encoder *encoder,
			       struct drm_display_mode *mode,
			       struct drm_display_mode *adjusted_mode)
{
	mode = adjusted_mode;

	DBG("set mode: %d:\"%s\" %d %d %d %d %d %d %d %d %d %d 0x%x 0x%x",
			mode->base.id, mode->name,
			mode->vrefresh, mode->clock,
			mode->hdisplay, mode->hsync_start,
			mode->hsync_end, mode->htotal,
			mode->vdisplay, mode->vsync_start,
			mode->vsync_end, mode->vtotal,
			mode->type, mode->flags);
	pingpong_tearcheck_setup(encoder, mode);
	mdp5_crtc_set_pipeline(encoder->crtc);
}

void mdp5_cmd_encoder_disable(struct drm_encoder *encoder)
{
	struct mdp5_encoder *mdp5_cmd_enc = to_mdp5_encoder(encoder);
	struct mdp5_ctl *ctl = mdp5_cmd_enc->ctl;
	struct mdp5_interface *intf = mdp5_cmd_enc->intf;
	struct mdp5_pipeline *pipeline = mdp5_crtc_get_pipeline(encoder->crtc);

	if (WARN_ON(!mdp5_cmd_enc->enabled))
		return;

	pingpong_tearcheck_disable(encoder);

	mdp5_ctl_set_encoder_state(ctl, pipeline, false);
	mdp5_ctl_commit(ctl, pipeline, mdp_ctl_flush_mask_encoder(intf), true);

	bs_set(mdp5_cmd_enc, 0);

	mdp5_cmd_enc->enabled = false;
}

void mdp5_cmd_encoder_enable(struct drm_encoder *encoder)
{
	struct mdp5_encoder *mdp5_cmd_enc = to_mdp5_encoder(encoder);
	struct mdp5_ctl *ctl = mdp5_cmd_enc->ctl;
	struct mdp5_interface *intf = mdp5_cmd_enc->intf;
	struct mdp5_pipeline *pipeline = mdp5_crtc_get_pipeline(encoder->crtc);

	if (WARN_ON(mdp5_cmd_enc->enabled))
		return;

	bs_set(mdp5_cmd_enc, 1);
	if (pingpong_tearcheck_enable(encoder))
		return;

	mdp5_ctl_commit(ctl, pipeline, mdp_ctl_flush_mask_encoder(intf), true);

	mdp5_ctl_set_encoder_state(ctl, pipeline, true);

	mdp5_cmd_enc->enabled = true;
}

int mdp5_cmd_encoder_set_split_display(struct drm_encoder *encoder,
				       struct drm_encoder *slave_encoder)
{
	struct mdp5_encoder *mdp5_cmd_enc = to_mdp5_encoder(encoder);
	struct mdp5_kms *mdp5_kms;
	struct device *dev;
	int intf_num;
	u32 data = 0;

	if (!encoder || !slave_encoder)
		return -EINVAL;

	mdp5_kms = get_kms(encoder);
	intf_num = mdp5_cmd_enc->intf->num;

	/* Switch slave encoder's trigger MUX, to use the master's
	 * start signal for the slave encoder
	 */
	if (intf_num == 1)
		data |= MDP5_SPLIT_DPL_UPPER_INTF2_SW_TRG_MUX;
	else if (intf_num == 2)
		data |= MDP5_SPLIT_DPL_UPPER_INTF1_SW_TRG_MUX;
	else
		return -EINVAL;

	/* Smart Panel, Sync mode */
	data |= MDP5_SPLIT_DPL_UPPER_SMART_PANEL;

	dev = &mdp5_kms->pdev->dev;

	/* Make sure clocks are on when connectors calling this function. */
	pm_runtime_get_sync(dev);
	mdp5_write(mdp5_kms, REG_MDP5_SPLIT_DPL_UPPER, data);

	mdp5_write(mdp5_kms, REG_MDP5_SPLIT_DPL_LOWER,
		   MDP5_SPLIT_DPL_LOWER_SMART_PANEL);
	mdp5_write(mdp5_kms, REG_MDP5_SPLIT_DPL_EN, 1);
	pm_runtime_put_sync(dev);

	return 0;
}