/*
 * Copyright (C) 2016 Red Hat
 * Author: Rob Clark <robdclark@gmail.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License 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.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "mdp5_kms.h"

struct mdp5_hw_pipe *mdp5_pipe_assign(struct drm_atomic_state *s,
		struct drm_plane *plane, uint32_t caps, uint32_t blkcfg)
{
	struct msm_drm_private *priv = s->dev->dev_private;
	struct mdp5_kms *mdp5_kms = to_mdp5_kms(to_mdp_kms(priv->kms));
	struct mdp5_state *state;
	struct mdp5_hw_pipe_state *old_state, *new_state;
	struct mdp5_hw_pipe *hwpipe = NULL;
	int i;

	state = mdp5_get_state(s);
	if (IS_ERR(state))
		return ERR_CAST(state);

	/* grab old_state after mdp5_get_state(), since now we hold lock: */
	old_state = &mdp5_kms->state->hwpipe;
	new_state = &state->hwpipe;

	for (i = 0; i < mdp5_kms->num_hwpipes; i++) {
		struct mdp5_hw_pipe *cur = mdp5_kms->hwpipes[i];

		/* skip if already in-use.. check both new and old state,
		 * since we cannot immediately re-use a pipe that is
		 * released in the current update in some cases:
		 *  (1) mdp5 can have SMP (non-double-buffered)
		 *  (2) hw pipe previously assigned to different CRTC
		 *      (vblanks might not be aligned)
		 */
		if (new_state->hwpipe_to_plane[cur->idx] ||
				old_state->hwpipe_to_plane[cur->idx])
			continue;

		/* skip if doesn't support some required caps: */
		if (caps & ~cur->caps)
			continue;

		/* possible candidate, take the one with the
		 * fewest unneeded caps bits set:
		 */
		if (!hwpipe || (hweight_long(cur->caps & ~caps) <
				hweight_long(hwpipe->caps & ~caps)))
			hwpipe = cur;
	}

	if (!hwpipe)
		return ERR_PTR(-ENOMEM);

	if (mdp5_kms->smp) {
		int ret;

		DBG("%s: alloc SMP blocks", hwpipe->name);
		ret = mdp5_smp_assign(mdp5_kms->smp, &state->smp,
				hwpipe->pipe, blkcfg);
		if (ret)
			return ERR_PTR(-ENOMEM);

		hwpipe->blkcfg = blkcfg;
	}

	DBG("%s: assign to plane %s for caps %x",
			hwpipe->name, plane->name, caps);
	new_state->hwpipe_to_plane[hwpipe->idx] = plane;

	return hwpipe;
}

void mdp5_pipe_release(struct drm_atomic_state *s, struct mdp5_hw_pipe *hwpipe)
{
	struct msm_drm_private *priv = s->dev->dev_private;
	struct mdp5_kms *mdp5_kms = to_mdp5_kms(to_mdp_kms(priv->kms));
	struct mdp5_state *state = mdp5_get_state(s);
	struct mdp5_hw_pipe_state *new_state = &state->hwpipe;

	if (!hwpipe)
		return;

	if (WARN_ON(!new_state->hwpipe_to_plane[hwpipe->idx]))
		return;

	DBG("%s: release from plane %s", hwpipe->name,
		new_state->hwpipe_to_plane[hwpipe->idx]->name);

	if (mdp5_kms->smp) {
		DBG("%s: free SMP blocks", hwpipe->name);
		mdp5_smp_release(mdp5_kms->smp, &state->smp, hwpipe->pipe);
	}

	new_state->hwpipe_to_plane[hwpipe->idx] = NULL;
}

void mdp5_pipe_destroy(struct mdp5_hw_pipe *hwpipe)
{
	kfree(hwpipe);
}

struct mdp5_hw_pipe *mdp5_pipe_init(enum mdp5_pipe pipe,
		uint32_t reg_offset, uint32_t caps)
{
	struct mdp5_hw_pipe *hwpipe;

	hwpipe = kzalloc(sizeof(*hwpipe), GFP_KERNEL);
	if (!hwpipe)
		return ERR_PTR(-ENOMEM);

	hwpipe->name = pipe2name(pipe);
	hwpipe->pipe = pipe;
	hwpipe->reg_offset = reg_offset;
	hwpipe->caps = caps;
	hwpipe->flush_mask = mdp_ctl_flush_mask_pipe(pipe);

	spin_lock_init(&hwpipe->pipe_lock);

	return hwpipe;
}