/*
 * Copyright (c) 2014 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 "mdp5_kms.h"
#include "mdp5_ctl.h"

/*
 * CTL - MDP Control Pool Manager
 *
 * Controls are shared between all CRTCs.
 *
 * They are intended to be used for data path configuration.
 * The top level register programming describes the complete data path for
 * a specific data path ID - REG_MDP5_CTL_*(<id>, ...)
 *
 * Hardware capabilities determine the number of concurrent data paths
 *
 * In certain use cases (high-resolution dual pipe), one single CTL can be
 * shared across multiple CRTCs.
 *
 * Because the number of CTLs can be less than the number of CRTCs,
 * CTLs are dynamically allocated from a pool of CTLs, only once a CRTC is
 * requested by the client (in mdp5_crtc_mode_set()).
 */

struct mdp5_ctl {
	struct mdp5_ctl_manager *ctlm;

	u32 id;

	/* whether this CTL has been allocated or not: */
	bool busy;

	/* memory output connection (@see mdp5_ctl_mode): */
	u32 mode;

	/* REG_MDP5_CTL_*(<id>) registers access info + lock: */
	spinlock_t hw_lock;
	u32 reg_offset;

	/* flush mask used to commit CTL registers */
	u32 flush_mask;

	bool cursor_on;

	struct drm_crtc *crtc;
};

struct mdp5_ctl_manager {
	struct drm_device *dev;

	/* number of CTL / Layer Mixers in this hw config: */
	u32 nlm;
	u32 nctl;

	/* pool of CTLs + lock to protect resource allocation (ctls[i].busy) */
	spinlock_t pool_lock;
	struct mdp5_ctl ctls[MAX_CTL];
};

static inline
struct mdp5_kms *get_kms(struct mdp5_ctl_manager *ctl_mgr)
{
	struct msm_drm_private *priv = ctl_mgr->dev->dev_private;

	return to_mdp5_kms(to_mdp_kms(priv->kms));
}

static inline
void ctl_write(struct mdp5_ctl *ctl, u32 reg, u32 data)
{
	struct mdp5_kms *mdp5_kms = get_kms(ctl->ctlm);

	(void)ctl->reg_offset; /* TODO use this instead of mdp5_write */
	mdp5_write(mdp5_kms, reg, data);
}

static inline
u32 ctl_read(struct mdp5_ctl *ctl, u32 reg)
{
	struct mdp5_kms *mdp5_kms = get_kms(ctl->ctlm);

	(void)ctl->reg_offset; /* TODO use this instead of mdp5_write */
	return mdp5_read(mdp5_kms, reg);
}


int mdp5_ctl_set_intf(struct mdp5_ctl *ctl, enum mdp5_intf intf)
{
	unsigned long flags;
	static const enum mdp5_intfnum intfnum[] = {
			INTF0, INTF1, INTF2, INTF3,
	};

	spin_lock_irqsave(&ctl->hw_lock, flags);
	ctl_write(ctl, REG_MDP5_CTL_OP(ctl->id),
			MDP5_CTL_OP_MODE(ctl->mode) |
			MDP5_CTL_OP_INTF_NUM(intfnum[intf]));
	spin_unlock_irqrestore(&ctl->hw_lock, flags);

	return 0;
}

int mdp5_ctl_set_cursor(struct mdp5_ctl *ctl, bool enable)
{
	struct mdp5_ctl_manager *ctl_mgr = ctl->ctlm;
	unsigned long flags;
	u32 blend_cfg;
	int lm;

	lm = mdp5_crtc_get_lm(ctl->crtc);
	if (unlikely(WARN_ON(lm < 0))) {
		dev_err(ctl_mgr->dev->dev, "CTL %d cannot find LM: %d",
				ctl->id, lm);
		return -EINVAL;
	}

	spin_lock_irqsave(&ctl->hw_lock, flags);

	blend_cfg = ctl_read(ctl, REG_MDP5_CTL_LAYER_REG(ctl->id, lm));

	if (enable)
		blend_cfg |=  MDP5_CTL_LAYER_REG_CURSOR_OUT;
	else
		blend_cfg &= ~MDP5_CTL_LAYER_REG_CURSOR_OUT;

	ctl_write(ctl, REG_MDP5_CTL_LAYER_REG(ctl->id, lm), blend_cfg);

	spin_unlock_irqrestore(&ctl->hw_lock, flags);

	ctl->cursor_on = enable;

	return 0;
}


int mdp5_ctl_blend(struct mdp5_ctl *ctl, u32 lm, u32 blend_cfg)
{
	unsigned long flags;

	if (ctl->cursor_on)
		blend_cfg |=  MDP5_CTL_LAYER_REG_CURSOR_OUT;
	else
		blend_cfg &= ~MDP5_CTL_LAYER_REG_CURSOR_OUT;

	spin_lock_irqsave(&ctl->hw_lock, flags);
	ctl_write(ctl, REG_MDP5_CTL_LAYER_REG(ctl->id, lm), blend_cfg);
	spin_unlock_irqrestore(&ctl->hw_lock, flags);

	return 0;
}

int mdp5_ctl_commit(struct mdp5_ctl *ctl, u32 flush_mask)
{
	struct mdp5_ctl_manager *ctl_mgr = ctl->ctlm;
	unsigned long flags;

	if (flush_mask & MDP5_CTL_FLUSH_CURSOR_DUMMY) {
		int lm = mdp5_crtc_get_lm(ctl->crtc);

		if (unlikely(WARN_ON(lm < 0))) {
			dev_err(ctl_mgr->dev->dev, "CTL %d cannot find LM: %d",
					ctl->id, lm);
			return -EINVAL;
		}

		/* for current targets, cursor bit is the same as LM bit */
		flush_mask |= mdp_ctl_flush_mask_lm(lm);
	}

	spin_lock_irqsave(&ctl->hw_lock, flags);
	ctl_write(ctl, REG_MDP5_CTL_FLUSH(ctl->id), flush_mask);
	spin_unlock_irqrestore(&ctl->hw_lock, flags);

	return 0;
}

u32 mdp5_ctl_get_flush(struct mdp5_ctl *ctl)
{
	return ctl->flush_mask;
}

void mdp5_ctl_release(struct mdp5_ctl *ctl)
{
	struct mdp5_ctl_manager *ctl_mgr = ctl->ctlm;
	unsigned long flags;

	if (unlikely(WARN_ON(ctl->id >= MAX_CTL) || !ctl->busy)) {
		dev_err(ctl_mgr->dev->dev, "CTL %d in bad state (%d)",
				ctl->id, ctl->busy);
		return;
	}

	spin_lock_irqsave(&ctl_mgr->pool_lock, flags);
	ctl->busy = false;
	spin_unlock_irqrestore(&ctl_mgr->pool_lock, flags);

	DBG("CTL %d released", ctl->id);
}

/*
 * mdp5_ctl_request() - CTL dynamic allocation
 *
 * Note: Current implementation considers that we can only have one CRTC per CTL
 *
 * @return first free CTL
 */
struct mdp5_ctl *mdp5_ctlm_request(struct mdp5_ctl_manager *ctl_mgr,
		struct drm_crtc *crtc)
{
	struct mdp5_ctl *ctl = NULL;
	unsigned long flags;
	int c;

	spin_lock_irqsave(&ctl_mgr->pool_lock, flags);

	for (c = 0; c < ctl_mgr->nctl; c++)
		if (!ctl_mgr->ctls[c].busy)
			break;

	if (unlikely(c >= ctl_mgr->nctl)) {
		dev_err(ctl_mgr->dev->dev, "No more CTL available!");
		goto unlock;
	}

	ctl = &ctl_mgr->ctls[c];

	ctl->crtc = crtc;
	ctl->busy = true;
	DBG("CTL %d allocated", ctl->id);

unlock:
	spin_unlock_irqrestore(&ctl_mgr->pool_lock, flags);
	return ctl;
}

void mdp5_ctlm_hw_reset(struct mdp5_ctl_manager *ctl_mgr)
{
	unsigned long flags;
	int c;

	for (c = 0; c < ctl_mgr->nctl; c++) {
		struct mdp5_ctl *ctl = &ctl_mgr->ctls[c];

		spin_lock_irqsave(&ctl->hw_lock, flags);
		ctl_write(ctl, REG_MDP5_CTL_OP(ctl->id), 0);
		spin_unlock_irqrestore(&ctl->hw_lock, flags);
	}
}

void mdp5_ctlm_destroy(struct mdp5_ctl_manager *ctl_mgr)
{
	kfree(ctl_mgr);
}

struct mdp5_ctl_manager *mdp5_ctlm_init(struct drm_device *dev,
		void __iomem *mmio_base, const struct mdp5_cfg_hw *hw_cfg)
{
	struct mdp5_ctl_manager *ctl_mgr;
	const struct mdp5_sub_block *ctl_cfg = &hw_cfg->ctl;
	unsigned long flags;
	int c, ret;

	ctl_mgr = kzalloc(sizeof(*ctl_mgr), GFP_KERNEL);
	if (!ctl_mgr) {
		dev_err(dev->dev, "failed to allocate CTL manager\n");
		ret = -ENOMEM;
		goto fail;
	}

	if (unlikely(WARN_ON(ctl_cfg->count > MAX_CTL))) {
		dev_err(dev->dev, "Increase static pool size to at least %d\n",
				ctl_cfg->count);
		ret = -ENOSPC;
		goto fail;
	}

	/* initialize the CTL manager: */
	ctl_mgr->dev = dev;
	ctl_mgr->nlm = hw_cfg->lm.count;
	ctl_mgr->nctl = ctl_cfg->count;
	spin_lock_init(&ctl_mgr->pool_lock);

	/* initialize each CTL of the pool: */
	spin_lock_irqsave(&ctl_mgr->pool_lock, flags);
	for (c = 0; c < ctl_mgr->nctl; c++) {
		struct mdp5_ctl *ctl = &ctl_mgr->ctls[c];

		if (WARN_ON(!ctl_cfg->base[c])) {
			dev_err(dev->dev, "CTL_%d: base is null!\n", c);
			ret = -EINVAL;
			goto fail;
		}
		ctl->ctlm = ctl_mgr;
		ctl->id = c;
		ctl->mode = MODE_NONE;
		ctl->reg_offset = ctl_cfg->base[c];
		ctl->flush_mask = MDP5_CTL_FLUSH_CTL;
		ctl->busy = false;
		spin_lock_init(&ctl->hw_lock);
	}
	spin_unlock_irqrestore(&ctl_mgr->pool_lock, flags);
	DBG("Pool of %d CTLs created.", ctl_mgr->nctl);

	return ctl_mgr;

fail:
	if (ctl_mgr)
		mdp5_ctlm_destroy(ctl_mgr);

	return ERR_PTR(ret);
}