/*
 * Copyright (C) 2016 BayLibre, SAS
 * Author: Neil Armstrong <narmstrong@baylibre.com>
 * Copyright (C) 2015 Amlogic, Inc. All rights reserved.
 * Copyright (C) 2014 Endless Mobile
 *
 * 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; either version 2 of the
 * License, or (at your option) any later version.
 *
 * 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/>.
 *
 * Written by:
 *     Jasper St. Pierre <jstpierre@mecheye.net>
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/platform_device.h>
#include <drm/drmP.h>
#include <drm/drm_atomic.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_plane_helper.h>
#include <drm/drm_gem_cma_helper.h>
#include <drm/drm_fb_cma_helper.h>
#include <drm/drm_rect.h>

#include "meson_plane.h"
#include "meson_vpp.h"
#include "meson_viu.h"
#include "meson_canvas.h"
#include "meson_registers.h"

struct meson_plane {
	struct drm_plane base;
	struct meson_drm *priv;
};
#define to_meson_plane(x) container_of(x, struct meson_plane, base)

static int meson_plane_atomic_check(struct drm_plane *plane,
				    struct drm_plane_state *state)
{
	struct drm_crtc_state *crtc_state;

	if (!state->crtc)
		return 0;

	crtc_state = drm_atomic_get_crtc_state(state->state, state->crtc);
	if (IS_ERR(crtc_state))
		return PTR_ERR(crtc_state);

	return drm_atomic_helper_check_plane_state(state, crtc_state,
						   DRM_PLANE_HELPER_NO_SCALING,
						   DRM_PLANE_HELPER_NO_SCALING,
						   true, true);
}

/* Takes a fixed 16.16 number and converts it to integer. */
static inline int64_t fixed16_to_int(int64_t value)
{
	return value >> 16;
}

static void meson_plane_atomic_update(struct drm_plane *plane,
				      struct drm_plane_state *old_state)
{
	struct meson_plane *meson_plane = to_meson_plane(plane);
	struct drm_plane_state *state = plane->state;
	struct drm_framebuffer *fb = state->fb;
	struct meson_drm *priv = meson_plane->priv;
	struct drm_gem_cma_object *gem;
	struct drm_rect src = {
		.x1 = (state->src_x),
		.y1 = (state->src_y),
		.x2 = (state->src_x + state->src_w),
		.y2 = (state->src_y + state->src_h),
	};
	struct drm_rect dest = {
		.x1 = state->crtc_x,
		.y1 = state->crtc_y,
		.x2 = state->crtc_x + state->crtc_w,
		.y2 = state->crtc_y + state->crtc_h,
	};
	unsigned long flags;

	/*
	 * Update Coordinates
	 * Update Formats
	 * Update Buffer
	 * Enable Plane
	 */
	spin_lock_irqsave(&priv->drm->event_lock, flags);

	/* Enable OSD and BLK0, set max global alpha */
	priv->viu.osd1_ctrl_stat = OSD_ENABLE |
				   (0xFF << OSD_GLOBAL_ALPHA_SHIFT) |
				   OSD_BLK0_ENABLE;

	/* Set up BLK0 to point to the right canvas */
	priv->viu.osd1_blk0_cfg[0] = ((MESON_CANVAS_ID_OSD1 << OSD_CANVAS_SEL) |
				      OSD_ENDIANNESS_LE);

	/* On GXBB, Use the old non-HDR RGB2YUV converter */
	if (meson_vpu_is_compatible(priv, "amlogic,meson-gxbb-vpu"))
		priv->viu.osd1_blk0_cfg[0] |= OSD_OUTPUT_COLOR_RGB;

	switch (fb->format->format) {
	case DRM_FORMAT_XRGB8888:
		/* For XRGB, replace the pixel's alpha by 0xFF */
		writel_bits_relaxed(OSD_REPLACE_EN, OSD_REPLACE_EN,
				    priv->io_base + _REG(VIU_OSD1_CTRL_STAT2));
		priv->viu.osd1_blk0_cfg[0] |= OSD_BLK_MODE_32 |
					      OSD_COLOR_MATRIX_32_ARGB;
		break;
	case DRM_FORMAT_ARGB8888:
		/* For ARGB, use the pixel's alpha */
		writel_bits_relaxed(OSD_REPLACE_EN, 0,
				    priv->io_base + _REG(VIU_OSD1_CTRL_STAT2));
		priv->viu.osd1_blk0_cfg[0] |= OSD_BLK_MODE_32 |
					      OSD_COLOR_MATRIX_32_ARGB;
		break;
	case DRM_FORMAT_RGB888:
		priv->viu.osd1_blk0_cfg[0] |= OSD_BLK_MODE_24 |
					      OSD_COLOR_MATRIX_24_RGB;
		break;
	case DRM_FORMAT_RGB565:
		priv->viu.osd1_blk0_cfg[0] |= OSD_BLK_MODE_16 |
					      OSD_COLOR_MATRIX_16_RGB565;
		break;
	};

	if (state->crtc->mode.flags & DRM_MODE_FLAG_INTERLACE) {
		priv->viu.osd1_interlace = true;

		dest.y1 /= 2;
		dest.y2 /= 2;
	} else
		priv->viu.osd1_interlace = false;

	/*
	 * The format of these registers is (x2 << 16 | x1),
	 * where x2 is exclusive.
	 * e.g. +30x1920 would be (1919 << 16) | 30
	 */
	priv->viu.osd1_blk0_cfg[1] = ((fixed16_to_int(src.x2) - 1) << 16) |
					fixed16_to_int(src.x1);
	priv->viu.osd1_blk0_cfg[2] = ((fixed16_to_int(src.y2) - 1) << 16) |
					fixed16_to_int(src.y1);
	priv->viu.osd1_blk0_cfg[3] = ((dest.x2 - 1) << 16) | dest.x1;
	priv->viu.osd1_blk0_cfg[4] = ((dest.y2 - 1) << 16) | dest.y1;

	/* Update Canvas with buffer address */
	gem = drm_fb_cma_get_gem_obj(fb, 0);

	priv->viu.osd1_addr = gem->paddr;
	priv->viu.osd1_stride = fb->pitches[0];
	priv->viu.osd1_height = fb->height;

	spin_unlock_irqrestore(&priv->drm->event_lock, flags);
}

static void meson_plane_atomic_disable(struct drm_plane *plane,
				       struct drm_plane_state *old_state)
{
	struct meson_plane *meson_plane = to_meson_plane(plane);
	struct meson_drm *priv = meson_plane->priv;

	/* Disable OSD1 */
	writel_bits_relaxed(VPP_OSD1_POSTBLEND, 0,
			    priv->io_base + _REG(VPP_MISC));

}

static const struct drm_plane_helper_funcs meson_plane_helper_funcs = {
	.atomic_check	= meson_plane_atomic_check,
	.atomic_disable	= meson_plane_atomic_disable,
	.atomic_update	= meson_plane_atomic_update,
};

static const struct drm_plane_funcs meson_plane_funcs = {
	.update_plane		= drm_atomic_helper_update_plane,
	.disable_plane		= drm_atomic_helper_disable_plane,
	.destroy		= drm_plane_cleanup,
	.reset			= drm_atomic_helper_plane_reset,
	.atomic_duplicate_state = drm_atomic_helper_plane_duplicate_state,
	.atomic_destroy_state	= drm_atomic_helper_plane_destroy_state,
};

static const uint32_t supported_drm_formats[] = {
	DRM_FORMAT_ARGB8888,
	DRM_FORMAT_XRGB8888,
	DRM_FORMAT_RGB888,
	DRM_FORMAT_RGB565,
};

int meson_plane_create(struct meson_drm *priv)
{
	struct meson_plane *meson_plane;
	struct drm_plane *plane;

	meson_plane = devm_kzalloc(priv->drm->dev, sizeof(*meson_plane),
				   GFP_KERNEL);
	if (!meson_plane)
		return -ENOMEM;

	meson_plane->priv = priv;
	plane = &meson_plane->base;

	drm_universal_plane_init(priv->drm, plane, 0xFF,
				 &meson_plane_funcs,
				 supported_drm_formats,
				 ARRAY_SIZE(supported_drm_formats),
				 NULL,
				 DRM_PLANE_TYPE_PRIMARY, "meson_primary_plane");

	drm_plane_helper_add(plane, &meson_plane_helper_funcs);

	priv->primary_plane = plane;

	return 0;
}