drivers/gpu/drm/rcar-du/rcar_du_kms.c - kernel/msm-4.19 - Gitiles

 /*
  * rcar_du_kms.c  --  R-Car Display Unit Mode Setting
  *
  * Copyright (C) 2013-2014 Renesas Electronics Corporation
  *
  * Contact: Laurent Pinchart (laurent.pinchart@ideasonboard.com)
  *
  * 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.
  */

 #include <drm/drmP.h>
 #include <drm/drm_atomic.h>
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_crtc.h>
 #include <drm/drm_crtc_helper.h>
 #include <drm/drm_fb_cma_helper.h>
 #include <drm/drm_gem_cma_helper.h>

 #include <linux/of_graph.h>
 #include <linux/wait.h>

 #include "rcar_du_crtc.h"
 #include "rcar_du_drv.h"
 #include "rcar_du_encoder.h"
 #include "rcar_du_kms.h"
 #include "rcar_du_lvdsenc.h"
 #include "rcar_du_regs.h"

 /* -----------------------------------------------------------------------------
  * Format helpers
  */

 static const struct rcar_du_format_info rcar_du_format_infos[] = {
 	{
 		.fourcc = DRM_FORMAT_RGB565,
 		.bpp = 16,
 		.planes = 1,
 		.pnmr = PnMR_SPIM_TP | PnMR_DDDF_16BPP,
 		.edf = PnDDCR4_EDF_NONE,
 	}, {
 		.fourcc = DRM_FORMAT_ARGB1555,
 		.bpp = 16,
 		.planes = 1,
 		.pnmr = PnMR_SPIM_ALP | PnMR_DDDF_ARGB,
 		.edf = PnDDCR4_EDF_NONE,
 	}, {
 		.fourcc = DRM_FORMAT_XRGB1555,
 		.bpp = 16,
 		.planes = 1,
 		.pnmr = PnMR_SPIM_ALP | PnMR_DDDF_ARGB,
 		.edf = PnDDCR4_EDF_NONE,
 	}, {
 		.fourcc = DRM_FORMAT_XRGB8888,
 		.bpp = 32,
 		.planes = 1,
 		.pnmr = PnMR_SPIM_TP | PnMR_DDDF_16BPP,
 		.edf = PnDDCR4_EDF_RGB888,
 	}, {
 		.fourcc = DRM_FORMAT_ARGB8888,
 		.bpp = 32,
 		.planes = 1,
 		.pnmr = PnMR_SPIM_ALP | PnMR_DDDF_16BPP,
 		.edf = PnDDCR4_EDF_ARGB8888,
 	}, {
 		.fourcc = DRM_FORMAT_UYVY,
 		.bpp = 16,
 		.planes = 1,
 		.pnmr = PnMR_SPIM_TP_OFF | PnMR_DDDF_YC,
 		.edf = PnDDCR4_EDF_NONE,
 	}, {
 		.fourcc = DRM_FORMAT_YUYV,
 		.bpp = 16,
 		.planes = 1,
 		.pnmr = PnMR_SPIM_TP_OFF | PnMR_DDDF_YC,
 		.edf = PnDDCR4_EDF_NONE,
 	}, {
 		.fourcc = DRM_FORMAT_NV12,
 		.bpp = 12,
 		.planes = 2,
 		.pnmr = PnMR_SPIM_TP_OFF | PnMR_DDDF_YC,
 		.edf = PnDDCR4_EDF_NONE,
 	}, {
 		.fourcc = DRM_FORMAT_NV21,
 		.bpp = 12,
 		.planes = 2,
 		.pnmr = PnMR_SPIM_TP_OFF | PnMR_DDDF_YC,
 		.edf = PnDDCR4_EDF_NONE,
 	}, {
 		/* In YUV 4:2:2, only NV16 is supported (NV61 isn't) */
 		.fourcc = DRM_FORMAT_NV16,
 		.bpp = 16,
 		.planes = 2,
 		.pnmr = PnMR_SPIM_TP_OFF | PnMR_DDDF_YC,
 		.edf = PnDDCR4_EDF_NONE,
 	},
 };

 const struct rcar_du_format_info *rcar_du_format_info(u32 fourcc)
 {
 	unsigned int i;

 	for (i = 0; i < ARRAY_SIZE(rcar_du_format_infos); ++i) {
 		if (rcar_du_format_infos[i].fourcc == fourcc)
 			return &rcar_du_format_infos[i];
 	}

 	return NULL;
 }

 /* -----------------------------------------------------------------------------
  * Frame buffer
  */

 int rcar_du_dumb_create(struct drm_file *file, struct drm_device *dev,
 			struct drm_mode_create_dumb *args)
 {
 	struct rcar_du_device *rcdu = dev->dev_private;
 	unsigned int min_pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
 	unsigned int align;

 	/* The R8A7779 DU requires a 16 pixels pitch alignment as documented,
 	 * but the R8A7790 DU seems to require a 128 bytes pitch alignment.
 	 */
 	if (rcar_du_needs(rcdu, RCAR_DU_QUIRK_ALIGN_128B))
 		align = 128;
 	else
 		align = 16 * args->bpp / 8;

 	args->pitch = roundup(min_pitch, align);

 	return drm_gem_cma_dumb_create_internal(file, dev, args);
 }

 static struct drm_framebuffer *
 rcar_du_fb_create(struct drm_device *dev, struct drm_file *file_priv,
 		  struct drm_mode_fb_cmd2 *mode_cmd)
 {
 	struct rcar_du_device *rcdu = dev->dev_private;
 	const struct rcar_du_format_info *format;
 	unsigned int max_pitch;
 	unsigned int align;
 	unsigned int bpp;

 	format = rcar_du_format_info(mode_cmd->pixel_format);
 	if (format == NULL) {
 		dev_dbg(dev->dev, "unsupported pixel format %08x\n",
 			mode_cmd->pixel_format);
 		return ERR_PTR(-EINVAL);
 	}

 	/*
 	 * The pitch and alignment constraints are expressed in pixels on the
 	 * hardware side and in bytes in the DRM API.
 	 */
 	bpp = format->planes == 2 ? 1 : format->bpp / 8;
 	max_pitch =  4096 * bpp;

 	if (rcar_du_needs(rcdu, RCAR_DU_QUIRK_ALIGN_128B))
 		align = 128;
 	else
 		align = 16 * bpp;

 	if (mode_cmd->pitches[0] & (align - 1) ||
 	    mode_cmd->pitches[0] >= max_pitch) {
 		dev_dbg(dev->dev, "invalid pitch value %u\n",
 			mode_cmd->pitches[0]);
 		return ERR_PTR(-EINVAL);
 	}

 	if (format->planes == 2) {
 		if (mode_cmd->pitches[1] != mode_cmd->pitches[0]) {
 			dev_dbg(dev->dev,
 				"luma and chroma pitches do not match\n");
 			return ERR_PTR(-EINVAL);
 		}
 	}

 	return drm_fb_cma_create(dev, file_priv, mode_cmd);
 }

 static void rcar_du_output_poll_changed(struct drm_device *dev)
 {
 	struct rcar_du_device *rcdu = dev->dev_private;

 	drm_fbdev_cma_hotplug_event(rcdu->fbdev);
 }

 /* -----------------------------------------------------------------------------
  * Atomic Check and Update
  */

 /*
  * Atomic hardware plane allocator
  *
  * The hardware plane allocator is solely based on the atomic plane states
  * without keeping any external state to avoid races between .atomic_check()
  * and .atomic_commit().
  *
  * The core idea is to avoid using a free planes bitmask that would need to be
  * shared between check and commit handlers with a collective knowledge based on
  * the allocated hardware plane(s) for each KMS plane. The allocator then loops
  * over all plane states to compute the free planes bitmask, allocates hardware
  * planes based on that bitmask, and stores the result back in the plane states.
  *
  * For this to work we need to access the current state of planes not touched by
  * the atomic update. To ensure that it won't be modified, we need to lock all
  * planes using drm_atomic_get_plane_state(). This effectively serializes atomic
  * updates from .atomic_check() up to completion (when swapping the states if
  * the check step has succeeded) or rollback (when freeing the states if the
  * check step has failed).
  *
  * Allocation is performed in the .atomic_check() handler and applied
  * automatically when the core swaps the old and new states.
  */

 static bool rcar_du_plane_needs_realloc(struct rcar_du_plane *plane,
 					struct rcar_du_plane_state *state)
 {
 	const struct rcar_du_format_info *cur_format;

 	cur_format = to_rcar_du_plane_state(plane->plane.state)->format;

 	/* Lowering the number of planes doesn't strictly require reallocation
 	 * as the extra hardware plane will be freed when committing, but doing
 	 * so could lead to more fragmentation.
 	 */
 	return !cur_format || cur_format->planes != state->format->planes;
 }

 static unsigned int rcar_du_plane_hwmask(struct rcar_du_plane_state *state)
 {
 	unsigned int mask;

 	if (state->hwindex == -1)
 		return 0;

 	mask = 1 << state->hwindex;
 	if (state->format->planes == 2)
 		mask |= 1 << ((state->hwindex + 1) % 8);

 	return mask;
 }

 static int rcar_du_plane_hwalloc(unsigned int num_planes, unsigned int free)
 {
 	unsigned int i;

 	for (i = 0; i < RCAR_DU_NUM_HW_PLANES; ++i) {
 		if (!(free & (1 << i)))
 			continue;

 		if (num_planes == 1 || free & (1 << ((i + 1) % 8)))
 			break;
 	}

 	return i == RCAR_DU_NUM_HW_PLANES ? -EBUSY : i;
 }

 static int rcar_du_atomic_check(struct drm_device *dev,
 				struct drm_atomic_state *state)
 {
 	struct rcar_du_device *rcdu = dev->dev_private;
 	unsigned int group_freed_planes[RCAR_DU_MAX_GROUPS] = { 0, };
 	unsigned int group_free_planes[RCAR_DU_MAX_GROUPS] = { 0, };
 	bool needs_realloc = false;
 	unsigned int groups = 0;
 	unsigned int i;
 	int ret;

 	ret = drm_atomic_helper_check(dev, state);
 	if (ret < 0)
 		return ret;

 	/* Check if hardware planes need to be reallocated. */
 	for (i = 0; i < dev->mode_config.num_total_plane; ++i) {
 		struct rcar_du_plane_state *plane_state;
 		struct rcar_du_plane *plane;
 		unsigned int index;

 		if (!state->planes[i])
 			continue;

 		plane = to_rcar_plane(state->planes[i]);
 		plane_state = to_rcar_du_plane_state(state->plane_states[i]);

 		/* If the plane is being disabled we don't need to go through
 		 * the full reallocation procedure. Just mark the hardware
 		 * plane(s) as freed.
 		 */
 		if (!plane_state->format) {
 			index = plane - plane->group->planes.planes;
 			group_freed_planes[plane->group->index] |= 1 << index;
 			plane_state->hwindex = -1;
 			continue;
 		}

 		/* If the plane needs to be reallocated mark it as such, and
 		 * mark the hardware plane(s) as free.
 		 */
 		if (rcar_du_plane_needs_realloc(plane, plane_state)) {
 			groups |= 1 << plane->group->index;
 			needs_realloc = true;

 			index = plane - plane->group->planes.planes;
 			group_freed_planes[plane->group->index] |= 1 << index;
 			plane_state->hwindex = -1;
 		}
 	}

 	if (!needs_realloc)
 		return 0;

 	/* Grab all plane states for the groups that need reallocation to ensure
 	 * locking and avoid racy updates. This serializes the update operation,
 	 * but there's not much we can do about it as that's the hardware
 	 * design.
 	 *
 	 * Compute the used planes mask for each group at the same time to avoid
 	 * looping over the planes separately later.
 	 */
 	while (groups) {
 		unsigned int index = ffs(groups) - 1;
 		struct rcar_du_group *group = &rcdu->groups[index];
 		unsigned int used_planes = 0;

 		for (i = 0; i < RCAR_DU_NUM_KMS_PLANES; ++i) {
 			struct rcar_du_plane *plane = &group->planes.planes[i];
 			struct rcar_du_plane_state *plane_state;
 			struct drm_plane_state *s;

 			s = drm_atomic_get_plane_state(state, &plane->plane);
 			if (IS_ERR(s))
 				return PTR_ERR(s);

 			/* If the plane has been freed in the above loop its
 			 * hardware planes must not be added to the used planes
 			 * bitmask. However, the current state doesn't reflect
 			 * the free state yet, as we've modified the new state
 			 * above. Use the local freed planes list to check for
 			 * that condition instead.
 			 */
 			if (group_freed_planes[index] & (1 << i))
 				continue;

 			plane_state = to_rcar_du_plane_state(plane->plane.state);
 			used_planes |= rcar_du_plane_hwmask(plane_state);
 		}

 		group_free_planes[index] = 0xff & ~used_planes;
 		groups &= ~(1 << index);
 	}

 	/* Reallocate hardware planes for each plane that needs it. */
 	for (i = 0; i < dev->mode_config.num_total_plane; ++i) {
 		struct rcar_du_plane_state *plane_state;
 		struct rcar_du_plane *plane;
 		int idx;

 		if (!state->planes[i])
 			continue;

 		plane = to_rcar_plane(state->planes[i]);
 		plane_state = to_rcar_du_plane_state(state->plane_states[i]);

 		/* Skip planes that are being disabled or don't need to be
 		 * reallocated.
 		 */
 		if (!plane_state->format ||
 		    !rcar_du_plane_needs_realloc(plane, plane_state))
 			continue;

 		idx = rcar_du_plane_hwalloc(plane_state->format->planes,
 					group_free_planes[plane->group->index]);
 		if (idx < 0) {
 			dev_dbg(rcdu->dev, "%s: no available hardware plane\n",
 				__func__);
 			return idx;
 		}

 		plane_state->hwindex = idx;

 		group_free_planes[plane->group->index] &=
 			~rcar_du_plane_hwmask(plane_state);
 	}

 	return 0;
 }

 struct rcar_du_commit {
 	struct work_struct work;
 	struct drm_device *dev;
 	struct drm_atomic_state *state;
 	u32 crtcs;
 };

 static void rcar_du_atomic_complete(struct rcar_du_commit *commit)
 {
 	struct drm_device *dev = commit->dev;
 	struct rcar_du_device *rcdu = dev->dev_private;
 	struct drm_atomic_state *old_state = commit->state;

 	/* Apply the atomic update. */
 	drm_atomic_helper_commit_modeset_disables(dev, old_state);
 	drm_atomic_helper_commit_modeset_enables(dev, old_state);
 	drm_atomic_helper_commit_planes(dev, old_state);

 	drm_atomic_helper_wait_for_vblanks(dev, old_state);

 	drm_atomic_helper_cleanup_planes(dev, old_state);

 	drm_atomic_state_free(old_state);

 	/* Complete the commit, wake up any waiter. */
 	spin_lock(&rcdu->commit.wait.lock);
 	rcdu->commit.pending &= ~commit->crtcs;
 	wake_up_all_locked(&rcdu->commit.wait);
 	spin_unlock(&rcdu->commit.wait.lock);

 	kfree(commit);
 }

 static void rcar_du_atomic_work(struct work_struct *work)
 {
 	struct rcar_du_commit *commit =
 		container_of(work, struct rcar_du_commit, work);

 	rcar_du_atomic_complete(commit);
 }

 static int rcar_du_atomic_commit(struct drm_device *dev,
 				 struct drm_atomic_state *state, bool async)
 {
 	struct rcar_du_device *rcdu = dev->dev_private;
 	struct rcar_du_commit *commit;
 	unsigned int i;
 	int ret;

 	ret = drm_atomic_helper_prepare_planes(dev, state);
 	if (ret)
 		return ret;

 	/* Allocate the commit object. */
 	commit = kzalloc(sizeof(*commit), GFP_KERNEL);
 	if (commit == NULL)
 		return -ENOMEM;

 	INIT_WORK(&commit->work, rcar_du_atomic_work);
 	commit->dev = dev;
 	commit->state = state;

 	/* Wait until all affected CRTCs have completed previous commits and
 	 * mark them as pending.
 	 */
 	for (i = 0; i < dev->mode_config.num_crtc; ++i) {
 		if (state->crtcs[i])
 			commit->crtcs |= 1 << drm_crtc_index(state->crtcs[i]);
 	}

 	spin_lock(&rcdu->commit.wait.lock);
 	ret = wait_event_interruptible_locked(rcdu->commit.wait,
 			!(rcdu->commit.pending & commit->crtcs));
 	if (ret == 0)
 		rcdu->commit.pending |= commit->crtcs;
 	spin_unlock(&rcdu->commit.wait.lock);

 	if (ret) {
 		kfree(commit);
 		return ret;
 	}

 	/* Swap the state, this is the point of no return. */
 	drm_atomic_helper_swap_state(dev, state);

 	if (async)
 		schedule_work(&commit->work);
 	else
 		rcar_du_atomic_complete(commit);

 	return 0;
 }

 /* -----------------------------------------------------------------------------
  * Initialization
  */

 static const struct drm_mode_config_funcs rcar_du_mode_config_funcs = {
 	.fb_create = rcar_du_fb_create,
 	.output_poll_changed = rcar_du_output_poll_changed,
 	.atomic_check = rcar_du_atomic_check,
 	.atomic_commit = rcar_du_atomic_commit,
 };

 static int rcar_du_encoders_init_one(struct rcar_du_device *rcdu,
 				     enum rcar_du_output output,
 				     struct of_endpoint *ep)
 {
 	static const struct {
 		const char *compatible;
 		enum rcar_du_encoder_type type;
 	} encoders[] = {
 		{ "adi,adv7123", RCAR_DU_ENCODER_VGA },
 		{ "adi,adv7511w", RCAR_DU_ENCODER_HDMI },
 		{ "thine,thc63lvdm83d", RCAR_DU_ENCODER_LVDS },
 	};

 	enum rcar_du_encoder_type enc_type = RCAR_DU_ENCODER_NONE;
 	struct device_node *connector = NULL;
 	struct device_node *encoder = NULL;
 	struct device_node *prev = NULL;
 	struct device_node *entity_ep_node;
 	struct device_node *entity;
 	int ret;

 	/*
 	 * Locate the connected entity and infer its type from the number of
 	 * endpoints.
 	 */
 	entity = of_graph_get_remote_port_parent(ep->local_node);
 	if (!entity) {
 		dev_dbg(rcdu->dev, "unconnected endpoint %s, skipping\n",
 			ep->local_node->full_name);
 		return 0;
 	}

 	entity_ep_node = of_parse_phandle(ep->local_node, "remote-endpoint", 0);

 	while (1) {
 		struct device_node *ep_node;

 		ep_node = of_graph_get_next_endpoint(entity, prev);
 		of_node_put(prev);
 		prev = ep_node;

 		if (!ep_node)
 			break;

 		if (ep_node == entity_ep_node)
 			continue;

 		/*
 		 * We've found one endpoint other than the input, this must
 		 * be an encoder. Locate the connector.
 		 */
 		encoder = entity;
 		connector = of_graph_get_remote_port_parent(ep_node);
 		of_node_put(ep_node);

 		if (!connector) {
 			dev_warn(rcdu->dev,
 				 "no connector for encoder %s, skipping\n",
 				 encoder->full_name);
 			of_node_put(entity_ep_node);
 			of_node_put(encoder);
 			return 0;
 		}

 		break;
 	}

 	of_node_put(entity_ep_node);

 	if (encoder) {
 		/*
 		 * If an encoder has been found, get its type based on its
 		 * compatible string.
 		 */
 		unsigned int i;

 		for (i = 0; i < ARRAY_SIZE(encoders); ++i) {
 			if (of_device_is_compatible(encoder,
 						    encoders[i].compatible)) {
 				enc_type = encoders[i].type;
 				break;
 			}
 		}

 		if (i == ARRAY_SIZE(encoders)) {
 			dev_warn(rcdu->dev,
 				 "unknown encoder type for %s, skipping\n",
 				 encoder->full_name);
 			of_node_put(encoder);
 			of_node_put(connector);
 			return 0;
 		}
 	} else {
 		/*
 		 * If no encoder has been found the entity must be the
 		 * connector.
 		 */
 		connector = entity;
 	}

 	ret = rcar_du_encoder_init(rcdu, enc_type, output, encoder, connector);
 	of_node_put(encoder);
 	of_node_put(connector);

 	return ret < 0 ? ret : 1;
 }

 static int rcar_du_encoders_init(struct rcar_du_device *rcdu)
 {
 	struct device_node *np = rcdu->dev->of_node;
 	struct device_node *prev = NULL;
 	unsigned int num_encoders = 0;

 	/*
 	 * Iterate over the endpoints and create one encoder for each output
 	 * pipeline.
 	 */
 	while (1) {
 		struct device_node *ep_node;
 		enum rcar_du_output output;
 		struct of_endpoint ep;
 		unsigned int i;
 		int ret;

 		ep_node = of_graph_get_next_endpoint(np, prev);
 		of_node_put(prev);
 		prev = ep_node;

 		if (ep_node == NULL)
 			break;

 		ret = of_graph_parse_endpoint(ep_node, &ep);
 		if (ret < 0) {
 			of_node_put(ep_node);
 			return ret;
 		}

 		/* Find the output route corresponding to the port number. */
 		for (i = 0; i < RCAR_DU_OUTPUT_MAX; ++i) {
 			if (rcdu->info->routes[i].possible_crtcs &&
 			    rcdu->info->routes[i].port == ep.port) {
 				output = i;
 				break;
 			}
 		}

 		if (i == RCAR_DU_OUTPUT_MAX) {
 			dev_warn(rcdu->dev,
 				 "port %u references unexisting output, skipping\n",
 				 ep.port);
 			continue;
 		}

 		/* Process the output pipeline. */
 		ret = rcar_du_encoders_init_one(rcdu, output, &ep);
 		if (ret < 0) {
 			if (ret == -EPROBE_DEFER) {
 				of_node_put(ep_node);
 				return ret;
 			}

 			dev_info(rcdu->dev,
 				 "encoder initialization failed, skipping\n");
 			continue;
 		}

 		num_encoders += ret;
 	}

 	return num_encoders;
 }

 int rcar_du_modeset_init(struct rcar_du_device *rcdu)
 {
 	static const unsigned int mmio_offsets[] = {
 		DU0_REG_OFFSET, DU2_REG_OFFSET
 	};

 	struct drm_device *dev = rcdu->ddev;
 	struct drm_encoder *encoder;
 	struct drm_fbdev_cma *fbdev;
 	unsigned int num_encoders;
 	unsigned int num_groups;
 	unsigned int i;
 	int ret;

 	drm_mode_config_init(dev);

 	dev->mode_config.min_width = 0;
 	dev->mode_config.min_height = 0;
 	dev->mode_config.max_width = 4095;
 	dev->mode_config.max_height = 2047;
 	dev->mode_config.funcs = &rcar_du_mode_config_funcs;

 	rcdu->num_crtcs = rcdu->info->num_crtcs;

 	/* Initialize the groups. */
 	num_groups = DIV_ROUND_UP(rcdu->num_crtcs, 2);

 	for (i = 0; i < num_groups; ++i) {
 		struct rcar_du_group *rgrp = &rcdu->groups[i];

 		mutex_init(&rgrp->lock);

 		rgrp->dev = rcdu;
 		rgrp->mmio_offset = mmio_offsets[i];
 		rgrp->index = i;

 		ret = rcar_du_planes_init(rgrp);
 		if (ret < 0)
 			return ret;
 	}

 	/* Create the CRTCs. */
 	for (i = 0; i < rcdu->num_crtcs; ++i) {
 		struct rcar_du_group *rgrp = &rcdu->groups[i / 2];

 		ret = rcar_du_crtc_create(rgrp, i);
 		if (ret < 0)
 			return ret;
 	}

 	/* Initialize the encoders. */
 	ret = rcar_du_lvdsenc_init(rcdu);
 	if (ret < 0)
 		return ret;

 	ret = rcar_du_encoders_init(rcdu);
 	if (ret < 0)
 		return ret;

 	if (ret == 0) {
 		dev_err(rcdu->dev, "error: no encoder could be initialized\n");
 		return -EINVAL;
 	}

 	num_encoders = ret;

 	/* Set the possible CRTCs and possible clones. There's always at least
 	 * one way for all encoders to clone each other, set all bits in the
 	 * possible clones field.
 	 */
 	list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 		struct rcar_du_encoder *renc = to_rcar_encoder(encoder);
 		const struct rcar_du_output_routing *route =
 			&rcdu->info->routes[renc->output];

 		encoder->possible_crtcs = route->possible_crtcs;
 		encoder->possible_clones = (1 << num_encoders) - 1;
 	}

 	drm_mode_config_reset(dev);

 	drm_kms_helper_poll_init(dev);

 	if (dev->mode_config.num_connector) {
 		fbdev = drm_fbdev_cma_init(dev, 32, dev->mode_config.num_crtc,
 					   dev->mode_config.num_connector);
 		if (IS_ERR(fbdev))
 			return PTR_ERR(fbdev);

 		rcdu->fbdev = fbdev;
 	} else {
 		dev_info(rcdu->dev,
 			 "no connector found, disabling fbdev emulation\n");
 	}

 	return 0;
 }
	/*
	* rcar_du_kms.c -- R-Car Display Unit Mode Setting
	*
	* Copyright (C) 2013-2014 Renesas Electronics Corporation
	*
	* Contact: Laurent Pinchart (laurent.pinchart@ideasonboard.com)
	*
	* 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.
	*/

	#include <drm/drmP.h>
	#include <drm/drm_atomic.h>
	#include <drm/drm_atomic_helper.h>
	#include <drm/drm_crtc.h>
	#include <drm/drm_crtc_helper.h>
	#include <drm/drm_fb_cma_helper.h>
	#include <drm/drm_gem_cma_helper.h>

	#include <linux/of_graph.h>
	#include <linux/wait.h>

	#include "rcar_du_crtc.h"
	#include "rcar_du_drv.h"
	#include "rcar_du_encoder.h"
	#include "rcar_du_kms.h"
	#include "rcar_du_lvdsenc.h"
	#include "rcar_du_regs.h"

	/* -----------------------------------------------------------------------------
	* Format helpers
	*/

	static const struct rcar_du_format_info rcar_du_format_infos[] = {
	{
	.fourcc = DRM_FORMAT_RGB565,
	.bpp = 16,
	.planes = 1,
	.pnmr = PnMR_SPIM_TP \| PnMR_DDDF_16BPP,
	.edf = PnDDCR4_EDF_NONE,
	}, {
	.fourcc = DRM_FORMAT_ARGB1555,
	.bpp = 16,
	.planes = 1,
	.pnmr = PnMR_SPIM_ALP \| PnMR_DDDF_ARGB,
	.edf = PnDDCR4_EDF_NONE,
	}, {
	.fourcc = DRM_FORMAT_XRGB1555,
	.bpp = 16,
	.planes = 1,
	.pnmr = PnMR_SPIM_ALP \| PnMR_DDDF_ARGB,
	.edf = PnDDCR4_EDF_NONE,
	}, {
	.fourcc = DRM_FORMAT_XRGB8888,
	.bpp = 32,
	.planes = 1,
	.pnmr = PnMR_SPIM_TP \| PnMR_DDDF_16BPP,
	.edf = PnDDCR4_EDF_RGB888,
	}, {
	.fourcc = DRM_FORMAT_ARGB8888,
	.bpp = 32,
	.planes = 1,
	.pnmr = PnMR_SPIM_ALP \| PnMR_DDDF_16BPP,
	.edf = PnDDCR4_EDF_ARGB8888,
	}, {
	.fourcc = DRM_FORMAT_UYVY,
	.bpp = 16,
	.planes = 1,
	.pnmr = PnMR_SPIM_TP_OFF \| PnMR_DDDF_YC,
	.edf = PnDDCR4_EDF_NONE,
	}, {
	.fourcc = DRM_FORMAT_YUYV,
	.bpp = 16,
	.planes = 1,
	.pnmr = PnMR_SPIM_TP_OFF \| PnMR_DDDF_YC,
	.edf = PnDDCR4_EDF_NONE,
	}, {
	.fourcc = DRM_FORMAT_NV12,
	.bpp = 12,
	.planes = 2,
	.pnmr = PnMR_SPIM_TP_OFF \| PnMR_DDDF_YC,
	.edf = PnDDCR4_EDF_NONE,
	}, {
	.fourcc = DRM_FORMAT_NV21,
	.bpp = 12,
	.planes = 2,
	.pnmr = PnMR_SPIM_TP_OFF \| PnMR_DDDF_YC,
	.edf = PnDDCR4_EDF_NONE,
	}, {
	/* In YUV 4:2:2, only NV16 is supported (NV61 isn't) */
	.fourcc = DRM_FORMAT_NV16,
	.bpp = 16,
	.planes = 2,
	.pnmr = PnMR_SPIM_TP_OFF \| PnMR_DDDF_YC,
	.edf = PnDDCR4_EDF_NONE,
	},
	};

	const struct rcar_du_format_info *rcar_du_format_info(u32 fourcc)
	{
	unsigned int i;

	for (i = 0; i < ARRAY_SIZE(rcar_du_format_infos); ++i) {
	if (rcar_du_format_infos[i].fourcc == fourcc)
	return &rcar_du_format_infos[i];
	}

	return NULL;
	}

	/* -----------------------------------------------------------------------------
	* Frame buffer
	*/

	int rcar_du_dumb_create(struct drm_file file, struct drm_device dev,
	struct drm_mode_create_dumb *args)
	{
	struct rcar_du_device *rcdu = dev->dev_private;
	unsigned int min_pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
	unsigned int align;

	/* The R8A7779 DU requires a 16 pixels pitch alignment as documented,
	* but the R8A7790 DU seems to require a 128 bytes pitch alignment.
	*/
	if (rcar_du_needs(rcdu, RCAR_DU_QUIRK_ALIGN_128B))
	align = 128;
	else
	align = 16 * args->bpp / 8;

	args->pitch = roundup(min_pitch, align);

	return drm_gem_cma_dumb_create_internal(file, dev, args);
	}

	static struct drm_framebuffer *
	rcar_du_fb_create(struct drm_device dev, struct drm_file file_priv,
	struct drm_mode_fb_cmd2 *mode_cmd)
	{
	struct rcar_du_device *rcdu = dev->dev_private;
	const struct rcar_du_format_info *format;
	unsigned int max_pitch;
	unsigned int align;
	unsigned int bpp;

	format = rcar_du_format_info(mode_cmd->pixel_format);
	if (format == NULL) {
	dev_dbg(dev->dev, "unsupported pixel format %08x\n",
	mode_cmd->pixel_format);
	return ERR_PTR(-EINVAL);
	}

	/*
	* The pitch and alignment constraints are expressed in pixels on the
	* hardware side and in bytes in the DRM API.
	*/
	bpp = format->planes == 2 ? 1 : format->bpp / 8;
	max_pitch = 4096 * bpp;

	if (rcar_du_needs(rcdu, RCAR_DU_QUIRK_ALIGN_128B))
	align = 128;
	else
	align = 16 * bpp;

	if (mode_cmd->pitches[0] & (align - 1) \|\|
	mode_cmd->pitches[0] >= max_pitch) {
	dev_dbg(dev->dev, "invalid pitch value %u\n",
	mode_cmd->pitches[0]);
	return ERR_PTR(-EINVAL);
	}

	if (format->planes == 2) {
	if (mode_cmd->pitches[1] != mode_cmd->pitches[0]) {
	dev_dbg(dev->dev,
	"luma and chroma pitches do not match\n");
	return ERR_PTR(-EINVAL);
	}
	}

	return drm_fb_cma_create(dev, file_priv, mode_cmd);
	}

	static void rcar_du_output_poll_changed(struct drm_device *dev)
	{
	struct rcar_du_device *rcdu = dev->dev_private;

	drm_fbdev_cma_hotplug_event(rcdu->fbdev);
	}

	/* -----------------------------------------------------------------------------
	* Atomic Check and Update
	*/

	/*
	* Atomic hardware plane allocator
	*
	* The hardware plane allocator is solely based on the atomic plane states
	* without keeping any external state to avoid races between .atomic_check()
	* and .atomic_commit().
	*
	* The core idea is to avoid using a free planes bitmask that would need to be
	* shared between check and commit handlers with a collective knowledge based on
	* the allocated hardware plane(s) for each KMS plane. The allocator then loops
	* over all plane states to compute the free planes bitmask, allocates hardware
	* planes based on that bitmask, and stores the result back in the plane states.
	*
	* For this to work we need to access the current state of planes not touched by
	* the atomic update. To ensure that it won't be modified, we need to lock all
	* planes using drm_atomic_get_plane_state(). This effectively serializes atomic
	* updates from .atomic_check() up to completion (when swapping the states if
	* the check step has succeeded) or rollback (when freeing the states if the
	* check step has failed).
	*
	* Allocation is performed in the .atomic_check() handler and applied
	* automatically when the core swaps the old and new states.
	*/

	static bool rcar_du_plane_needs_realloc(struct rcar_du_plane *plane,
	struct rcar_du_plane_state *state)
	{
	const struct rcar_du_format_info *cur_format;

	cur_format = to_rcar_du_plane_state(plane->plane.state)->format;

	/* Lowering the number of planes doesn't strictly require reallocation
	* as the extra hardware plane will be freed when committing, but doing
	* so could lead to more fragmentation.
	*/
	return !cur_format \|\| cur_format->planes != state->format->planes;
	}

	static unsigned int rcar_du_plane_hwmask(struct rcar_du_plane_state *state)
	{
	unsigned int mask;

	if (state->hwindex == -1)
	return 0;

	mask = 1 << state->hwindex;
	if (state->format->planes == 2)
	mask \|= 1 << ((state->hwindex + 1) % 8);

	return mask;
	}

	static int rcar_du_plane_hwalloc(unsigned int num_planes, unsigned int free)
	{
	unsigned int i;

	for (i = 0; i < RCAR_DU_NUM_HW_PLANES; ++i) {
	if (!(free & (1 << i)))
	continue;

	if (num_planes == 1 \|\| free & (1 << ((i + 1) % 8)))
	break;
	}

	return i == RCAR_DU_NUM_HW_PLANES ? -EBUSY : i;
	}

	static int rcar_du_atomic_check(struct drm_device *dev,
	struct drm_atomic_state *state)
	{
	struct rcar_du_device *rcdu = dev->dev_private;
	unsigned int group_freed_planes[RCAR_DU_MAX_GROUPS] = { 0, };
	unsigned int group_free_planes[RCAR_DU_MAX_GROUPS] = { 0, };
	bool needs_realloc = false;
	unsigned int groups = 0;
	unsigned int i;
	int ret;

	ret = drm_atomic_helper_check(dev, state);
	if (ret < 0)
	return ret;

	/* Check if hardware planes need to be reallocated. */
	for (i = 0; i < dev->mode_config.num_total_plane; ++i) {
	struct rcar_du_plane_state *plane_state;
	struct rcar_du_plane *plane;
	unsigned int index;

	if (!state->planes[i])
	continue;

	plane = to_rcar_plane(state->planes[i]);
	plane_state = to_rcar_du_plane_state(state->plane_states[i]);

	/* If the plane is being disabled we don't need to go through
	* the full reallocation procedure. Just mark the hardware
	* plane(s) as freed.
	*/
	if (!plane_state->format) {
	index = plane - plane->group->planes.planes;
	group_freed_planes[plane->group->index] \|= 1 << index;
	plane_state->hwindex = -1;
	continue;
	}

	/* If the plane needs to be reallocated mark it as such, and
	* mark the hardware plane(s) as free.
	*/
	if (rcar_du_plane_needs_realloc(plane, plane_state)) {
	groups \|= 1 << plane->group->index;
	needs_realloc = true;

	index = plane - plane->group->planes.planes;
	group_freed_planes[plane->group->index] \|= 1 << index;
	plane_state->hwindex = -1;
	}
	}

	if (!needs_realloc)
	return 0;

	/* Grab all plane states for the groups that need reallocation to ensure
	* locking and avoid racy updates. This serializes the update operation,
	* but there's not much we can do about it as that's the hardware
	* design.
	*
	* Compute the used planes mask for each group at the same time to avoid
	* looping over the planes separately later.
	*/
	while (groups) {
	unsigned int index = ffs(groups) - 1;
	struct rcar_du_group *group = &rcdu->groups[index];
	unsigned int used_planes = 0;

	for (i = 0; i < RCAR_DU_NUM_KMS_PLANES; ++i) {
	struct rcar_du_plane *plane = &group->planes.planes[i];
	struct rcar_du_plane_state *plane_state;
	struct drm_plane_state *s;

	s = drm_atomic_get_plane_state(state, &plane->plane);
	if (IS_ERR(s))
	return PTR_ERR(s);

	/* If the plane has been freed in the above loop its
	* hardware planes must not be added to the used planes
	* bitmask. However, the current state doesn't reflect
	* the free state yet, as we've modified the new state
	* above. Use the local freed planes list to check for
	* that condition instead.
	*/
	if (group_freed_planes[index] & (1 << i))
	continue;

	plane_state = to_rcar_du_plane_state(plane->plane.state);
	used_planes \|= rcar_du_plane_hwmask(plane_state);
	}

	group_free_planes[index] = 0xff & ~used_planes;
	groups &= ~(1 << index);
	}

	/* Reallocate hardware planes for each plane that needs it. */
	for (i = 0; i < dev->mode_config.num_total_plane; ++i) {
	struct rcar_du_plane_state *plane_state;
	struct rcar_du_plane *plane;
	int idx;

	if (!state->planes[i])
	continue;

	plane = to_rcar_plane(state->planes[i]);
	plane_state = to_rcar_du_plane_state(state->plane_states[i]);

	/* Skip planes that are being disabled or don't need to be
	* reallocated.
	*/
	if (!plane_state->format \|\|
	!rcar_du_plane_needs_realloc(plane, plane_state))
	continue;

	idx = rcar_du_plane_hwalloc(plane_state->format->planes,
	group_free_planes[plane->group->index]);
	if (idx < 0) {
	dev_dbg(rcdu->dev, "%s: no available hardware plane\n",
	__func__);
	return idx;
	}

	plane_state->hwindex = idx;

	group_free_planes[plane->group->index] &=
	~rcar_du_plane_hwmask(plane_state);
	}

	return 0;
	}

	struct rcar_du_commit {
	struct work_struct work;
	struct drm_device *dev;
	struct drm_atomic_state *state;
	u32 crtcs;
	};

	static void rcar_du_atomic_complete(struct rcar_du_commit *commit)
	{
	struct drm_device *dev = commit->dev;
	struct rcar_du_device *rcdu = dev->dev_private;
	struct drm_atomic_state *old_state = commit->state;

	/* Apply the atomic update. */
	drm_atomic_helper_commit_modeset_disables(dev, old_state);
	drm_atomic_helper_commit_modeset_enables(dev, old_state);
	drm_atomic_helper_commit_planes(dev, old_state);

	drm_atomic_helper_wait_for_vblanks(dev, old_state);

	drm_atomic_helper_cleanup_planes(dev, old_state);

	drm_atomic_state_free(old_state);

	/* Complete the commit, wake up any waiter. */
	spin_lock(&rcdu->commit.wait.lock);
	rcdu->commit.pending &= ~commit->crtcs;
	wake_up_all_locked(&rcdu->commit.wait);
	spin_unlock(&rcdu->commit.wait.lock);

	kfree(commit);
	}

	static void rcar_du_atomic_work(struct work_struct *work)
	{
	struct rcar_du_commit *commit =
	container_of(work, struct rcar_du_commit, work);

	rcar_du_atomic_complete(commit);
	}

	static int rcar_du_atomic_commit(struct drm_device *dev,
	struct drm_atomic_state *state, bool async)
	{
	struct rcar_du_device *rcdu = dev->dev_private;
	struct rcar_du_commit *commit;
	unsigned int i;
	int ret;

	ret = drm_atomic_helper_prepare_planes(dev, state);
	if (ret)
	return ret;

	/* Allocate the commit object. */
	commit = kzalloc(sizeof(*commit), GFP_KERNEL);
	if (commit == NULL)
	return -ENOMEM;

	INIT_WORK(&commit->work, rcar_du_atomic_work);
	commit->dev = dev;
	commit->state = state;

	/* Wait until all affected CRTCs have completed previous commits and
	* mark them as pending.
	*/
	for (i = 0; i < dev->mode_config.num_crtc; ++i) {
	if (state->crtcs[i])
	commit->crtcs \|= 1 << drm_crtc_index(state->crtcs[i]);
	}

	spin_lock(&rcdu->commit.wait.lock);
	ret = wait_event_interruptible_locked(rcdu->commit.wait,
	!(rcdu->commit.pending & commit->crtcs));
	if (ret == 0)
	rcdu->commit.pending \|= commit->crtcs;
	spin_unlock(&rcdu->commit.wait.lock);

	if (ret) {
	kfree(commit);
	return ret;
	}

	/* Swap the state, this is the point of no return. */
	drm_atomic_helper_swap_state(dev, state);

	if (async)
	schedule_work(&commit->work);
	else
	rcar_du_atomic_complete(commit);

	return 0;
	}

	/* -----------------------------------------------------------------------------
	* Initialization
	*/

	static const struct drm_mode_config_funcs rcar_du_mode_config_funcs = {
	.fb_create = rcar_du_fb_create,
	.output_poll_changed = rcar_du_output_poll_changed,
	.atomic_check = rcar_du_atomic_check,
	.atomic_commit = rcar_du_atomic_commit,
	};

	static int rcar_du_encoders_init_one(struct rcar_du_device *rcdu,
	enum rcar_du_output output,
	struct of_endpoint *ep)
	{
	static const struct {
	const char *compatible;
	enum rcar_du_encoder_type type;
	} encoders[] = {
	{ "adi,adv7123", RCAR_DU_ENCODER_VGA },
	{ "adi,adv7511w", RCAR_DU_ENCODER_HDMI },
	{ "thine,thc63lvdm83d", RCAR_DU_ENCODER_LVDS },
	};

	enum rcar_du_encoder_type enc_type = RCAR_DU_ENCODER_NONE;
	struct device_node *connector = NULL;
	struct device_node *encoder = NULL;
	struct device_node *prev = NULL;
	struct device_node *entity_ep_node;
	struct device_node *entity;
	int ret;

	/*
	* Locate the connected entity and infer its type from the number of
	* endpoints.
	*/
	entity = of_graph_get_remote_port_parent(ep->local_node);
	if (!entity) {
	dev_dbg(rcdu->dev, "unconnected endpoint %s, skipping\n",
	ep->local_node->full_name);
	return 0;
	}

	entity_ep_node = of_parse_phandle(ep->local_node, "remote-endpoint", 0);

	while (1) {
	struct device_node *ep_node;

	ep_node = of_graph_get_next_endpoint(entity, prev);
	of_node_put(prev);
	prev = ep_node;

	if (!ep_node)
	break;

	if (ep_node == entity_ep_node)
	continue;

	/*
	* We've found one endpoint other than the input, this must
	* be an encoder. Locate the connector.
	*/
	encoder = entity;
	connector = of_graph_get_remote_port_parent(ep_node);
	of_node_put(ep_node);

	if (!connector) {
	dev_warn(rcdu->dev,
	"no connector for encoder %s, skipping\n",
	encoder->full_name);
	of_node_put(entity_ep_node);
	of_node_put(encoder);
	return 0;
	}

	break;
	}

	of_node_put(entity_ep_node);

	if (encoder) {
	/*
	* If an encoder has been found, get its type based on its
	* compatible string.
	*/
	unsigned int i;

	for (i = 0; i < ARRAY_SIZE(encoders); ++i) {
	if (of_device_is_compatible(encoder,
	encoders[i].compatible)) {
	enc_type = encoders[i].type;
	break;
	}
	}

	if (i == ARRAY_SIZE(encoders)) {
	dev_warn(rcdu->dev,
	"unknown encoder type for %s, skipping\n",
	encoder->full_name);
	of_node_put(encoder);
	of_node_put(connector);
	return 0;
	}
	} else {
	/*
	* If no encoder has been found the entity must be the
	* connector.
	*/
	connector = entity;
	}

	ret = rcar_du_encoder_init(rcdu, enc_type, output, encoder, connector);
	of_node_put(encoder);
	of_node_put(connector);

	return ret < 0 ? ret : 1;
	}

	static int rcar_du_encoders_init(struct rcar_du_device *rcdu)
	{
	struct device_node *np = rcdu->dev->of_node;
	struct device_node *prev = NULL;
	unsigned int num_encoders = 0;

	/*
	* Iterate over the endpoints and create one encoder for each output
	* pipeline.
	*/
	while (1) {
	struct device_node *ep_node;
	enum rcar_du_output output;
	struct of_endpoint ep;
	unsigned int i;
	int ret;

	ep_node = of_graph_get_next_endpoint(np, prev);
	of_node_put(prev);
	prev = ep_node;

	if (ep_node == NULL)
	break;

	ret = of_graph_parse_endpoint(ep_node, &ep);
	if (ret < 0) {
	of_node_put(ep_node);
	return ret;
	}

	/* Find the output route corresponding to the port number. */
	for (i = 0; i < RCAR_DU_OUTPUT_MAX; ++i) {
	if (rcdu->info->routes[i].possible_crtcs &&
	rcdu->info->routes[i].port == ep.port) {
	output = i;
	break;
	}
	}

	if (i == RCAR_DU_OUTPUT_MAX) {
	dev_warn(rcdu->dev,
	"port %u references unexisting output, skipping\n",
	ep.port);
	continue;
	}

	/* Process the output pipeline. */
	ret = rcar_du_encoders_init_one(rcdu, output, &ep);
	if (ret < 0) {
	if (ret == -EPROBE_DEFER) {
	of_node_put(ep_node);
	return ret;
	}

	dev_info(rcdu->dev,
	"encoder initialization failed, skipping\n");
	continue;
	}

	num_encoders += ret;
	}

	return num_encoders;
	}

	int rcar_du_modeset_init(struct rcar_du_device *rcdu)
	{
	static const unsigned int mmio_offsets[] = {
	DU0_REG_OFFSET, DU2_REG_OFFSET
	};

	struct drm_device *dev = rcdu->ddev;
	struct drm_encoder *encoder;
	struct drm_fbdev_cma *fbdev;
	unsigned int num_encoders;
	unsigned int num_groups;
	unsigned int i;
	int ret;

	drm_mode_config_init(dev);

	dev->mode_config.min_width = 0;
	dev->mode_config.min_height = 0;
	dev->mode_config.max_width = 4095;
	dev->mode_config.max_height = 2047;
	dev->mode_config.funcs = &rcar_du_mode_config_funcs;

	rcdu->num_crtcs = rcdu->info->num_crtcs;

	/* Initialize the groups. */
	num_groups = DIV_ROUND_UP(rcdu->num_crtcs, 2);

	for (i = 0; i < num_groups; ++i) {
	struct rcar_du_group *rgrp = &rcdu->groups[i];

	mutex_init(&rgrp->lock);

	rgrp->dev = rcdu;
	rgrp->mmio_offset = mmio_offsets[i];
	rgrp->index = i;

	ret = rcar_du_planes_init(rgrp);
	if (ret < 0)
	return ret;
	}

	/* Create the CRTCs. */
	for (i = 0; i < rcdu->num_crtcs; ++i) {
	struct rcar_du_group *rgrp = &rcdu->groups[i / 2];

	ret = rcar_du_crtc_create(rgrp, i);
	if (ret < 0)
	return ret;
	}

	/* Initialize the encoders. */
	ret = rcar_du_lvdsenc_init(rcdu);
	if (ret < 0)
	return ret;

	ret = rcar_du_encoders_init(rcdu);
	if (ret < 0)
	return ret;

	if (ret == 0) {
	dev_err(rcdu->dev, "error: no encoder could be initialized\n");
	return -EINVAL;
	}

	num_encoders = ret;

	/* Set the possible CRTCs and possible clones. There's always at least
	* one way for all encoders to clone each other, set all bits in the
	* possible clones field.
	*/
	list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
	struct rcar_du_encoder *renc = to_rcar_encoder(encoder);
	const struct rcar_du_output_routing *route =
	&rcdu->info->routes[renc->output];

	encoder->possible_crtcs = route->possible_crtcs;
	encoder->possible_clones = (1 << num_encoders) - 1;
	}

	drm_mode_config_reset(dev);

	drm_kms_helper_poll_init(dev);

	if (dev->mode_config.num_connector) {
	fbdev = drm_fbdev_cma_init(dev, 32, dev->mode_config.num_crtc,
	dev->mode_config.num_connector);
	if (IS_ERR(fbdev))
	return PTR_ERR(fbdev);

	rcdu->fbdev = fbdev;
	} else {
	dev_info(rcdu->dev,
	"no connector found, disabling fbdev emulation\n");
	}

	return 0;
	}