// SPDX-License-Identifier: GPL-2.0
/*
 * (C) COPYRIGHT 2018 ARM Limited. All rights reserved.
 * Author: James.Qian.Wang <james.qian.wang@arm.com>
 *
 */

#include <drm/drm_print.h>
#include <linux/clk.h>
#include "komeda_dev.h"
#include "komeda_kms.h"
#include "komeda_pipeline.h"
#include "komeda_framebuffer.h"

static inline bool is_switching_user(void *old, void *new)
{
	if (!old || !new)
		return false;

	return old != new;
}

static struct komeda_pipeline_state *
komeda_pipeline_get_state(struct komeda_pipeline *pipe,
			  struct drm_atomic_state *state)
{
	struct drm_private_state *priv_st;

	priv_st = drm_atomic_get_private_obj_state(state, &pipe->obj);
	if (IS_ERR(priv_st))
		return ERR_CAST(priv_st);

	return priv_to_pipe_st(priv_st);
}

struct komeda_pipeline_state *
komeda_pipeline_get_old_state(struct komeda_pipeline *pipe,
			      struct drm_atomic_state *state)
{
	struct drm_private_state *priv_st;

	priv_st = drm_atomic_get_old_private_obj_state(state, &pipe->obj);
	if (priv_st)
		return priv_to_pipe_st(priv_st);
	return NULL;
}

static struct komeda_pipeline_state *
komeda_pipeline_get_new_state(struct komeda_pipeline *pipe,
			      struct drm_atomic_state *state)
{
	struct drm_private_state *priv_st;

	priv_st = drm_atomic_get_new_private_obj_state(state, &pipe->obj);
	if (priv_st)
		return priv_to_pipe_st(priv_st);
	return NULL;
}

/* Assign pipeline for crtc */
static struct komeda_pipeline_state *
komeda_pipeline_get_state_and_set_crtc(struct komeda_pipeline *pipe,
				       struct drm_atomic_state *state,
				       struct drm_crtc *crtc)
{
	struct komeda_pipeline_state *st;

	st = komeda_pipeline_get_state(pipe, state);
	if (IS_ERR(st))
		return st;

	if (is_switching_user(crtc, st->crtc)) {
		DRM_DEBUG_ATOMIC("CRTC%d required pipeline%d is busy.\n",
				 drm_crtc_index(crtc), pipe->id);
		return ERR_PTR(-EBUSY);
	}

	/* pipeline only can be disabled when the it is free or unused */
	if (!crtc && st->active_comps) {
		DRM_DEBUG_ATOMIC("Disabling a busy pipeline:%d.\n", pipe->id);
		return ERR_PTR(-EBUSY);
	}

	st->crtc = crtc;

	if (crtc) {
		struct komeda_crtc_state *kcrtc_st;

		kcrtc_st = to_kcrtc_st(drm_atomic_get_new_crtc_state(state,
								     crtc));

		kcrtc_st->active_pipes |= BIT(pipe->id);
		kcrtc_st->affected_pipes |= BIT(pipe->id);
	}
	return st;
}

static struct komeda_component_state *
komeda_component_get_state(struct komeda_component *c,
			   struct drm_atomic_state *state)
{
	struct drm_private_state *priv_st;

	WARN_ON(!drm_modeset_is_locked(&c->pipeline->obj.lock));

	priv_st = drm_atomic_get_private_obj_state(state, &c->obj);
	if (IS_ERR(priv_st))
		return ERR_CAST(priv_st);

	return priv_to_comp_st(priv_st);
}

static struct komeda_component_state *
komeda_component_get_old_state(struct komeda_component *c,
			       struct drm_atomic_state *state)
{
	struct drm_private_state *priv_st;

	priv_st = drm_atomic_get_old_private_obj_state(state, &c->obj);
	if (priv_st)
		return priv_to_comp_st(priv_st);
	return NULL;
}

/**
 * komeda_component_get_state_and_set_user()
 *
 * @c: component to get state and set user
 * @state: global atomic state
 * @user: direct user, the binding user
 * @crtc: the CRTC user, the big boss :)
 *
 * This function accepts two users:
 * -   The direct user: can be plane/crtc/wb_connector depends on component
 * -   The big boss (CRTC)
 * CRTC is the big boss (the final user), because all component resources
 * eventually will be assigned to CRTC, like the layer will be binding to
 * kms_plane, but kms plane will be binding to a CRTC eventually.
 *
 * The big boss (CRTC) is for pipeline assignment, since &komeda_component isn't
 * independent and can be assigned to CRTC freely, but belongs to a specific
 * pipeline, only pipeline can be shared between crtc, and pipeline as a whole
 * (include all the internal components) assigned to a specific CRTC.
 *
 * So when set a user to komeda_component, need first to check the status of
 * component->pipeline to see if the pipeline is available on this specific
 * CRTC. if the pipeline is busy (assigned to another CRTC), even the required
 * component is free, the component still cannot be assigned to the direct user.
 */
static struct komeda_component_state *
komeda_component_get_state_and_set_user(struct komeda_component *c,
					struct drm_atomic_state *state,
					void *user,
					struct drm_crtc *crtc)
{
	struct komeda_pipeline_state *pipe_st;
	struct komeda_component_state *st;

	/* First check if the pipeline is available */
	pipe_st = komeda_pipeline_get_state_and_set_crtc(c->pipeline,
							 state, crtc);
	if (IS_ERR(pipe_st))
		return ERR_CAST(pipe_st);

	st = komeda_component_get_state(c, state);
	if (IS_ERR(st))
		return st;

	/* check if the component has been occupied */
	if (is_switching_user(user, st->binding_user)) {
		DRM_DEBUG_ATOMIC("required %s is busy.\n", c->name);
		return ERR_PTR(-EBUSY);
	}

	st->binding_user = user;
	/* mark the component as active if user is valid */
	if (st->binding_user)
		pipe_st->active_comps |= BIT(c->id);

	return st;
}

static void
komeda_component_add_input(struct komeda_component_state *state,
			   struct komeda_component_output *input,
			   int idx)
{
	struct komeda_component *c = state->component;

	WARN_ON((idx < 0 || idx >= c->max_active_inputs));

	/* since the inputs[i] is only valid when it is active. So if a input[i]
	 * is a newly enabled input which switches from disable to enable, then
	 * the old inputs[i] is undefined (NOT zeroed), we can not rely on
	 * memcmp, but directly mark it changed
	 */
	if (!has_bit(idx, state->affected_inputs) ||
	    memcmp(&state->inputs[idx], input, sizeof(*input))) {
		memcpy(&state->inputs[idx], input, sizeof(*input));
		state->changed_active_inputs |= BIT(idx);
	}
	state->active_inputs |= BIT(idx);
	state->affected_inputs |= BIT(idx);
}

static int
komeda_component_check_input(struct komeda_component_state *state,
			     struct komeda_component_output *input,
			     int idx)
{
	struct komeda_component *c = state->component;

	if ((idx < 0) || (idx >= c->max_active_inputs)) {
		DRM_DEBUG_ATOMIC("%s invalid input id: %d.\n", c->name, idx);
		return -EINVAL;
	}

	if (has_bit(idx, state->active_inputs)) {
		DRM_DEBUG_ATOMIC("%s required input_id: %d has been occupied already.\n",
				 c->name, idx);
		return -EINVAL;
	}

	return 0;
}

static void
komeda_component_set_output(struct komeda_component_output *output,
			    struct komeda_component *comp,
			    u8 output_port)
{
	output->component = comp;
	output->output_port = output_port;
}

static int
komeda_component_validate_private(struct komeda_component *c,
				  struct komeda_component_state *st)
{
	int err;

	if (!c->funcs->validate)
		return 0;

	err = c->funcs->validate(c, st);
	if (err)
		DRM_DEBUG_ATOMIC("%s validate private failed.\n", c->name);

	return err;
}

static int
komeda_layer_check_cfg(struct komeda_layer *layer,
		       struct komeda_plane_state *kplane_st,
		       struct komeda_data_flow_cfg *dflow)
{
	if (!in_range(&layer->hsize_in, dflow->in_w)) {
		DRM_DEBUG_ATOMIC("src_w: %d is out of range.\n", dflow->in_w);
		return -EINVAL;
	}

	if (!in_range(&layer->vsize_in, dflow->in_h)) {
		DRM_DEBUG_ATOMIC("src_h: %d is out of range.\n", dflow->in_h);
		return -EINVAL;
	}

	return 0;
}

static int
komeda_layer_validate(struct komeda_layer *layer,
		      struct komeda_plane_state *kplane_st,
		      struct komeda_data_flow_cfg *dflow)
{
	struct drm_plane_state *plane_st = &kplane_st->base;
	struct drm_framebuffer *fb = plane_st->fb;
	struct komeda_fb *kfb = to_kfb(fb);
	struct komeda_component_state *c_st;
	struct komeda_layer_state *st;
	int i, err;

	err = komeda_layer_check_cfg(layer, kplane_st, dflow);
	if (err)
		return err;

	c_st = komeda_component_get_state_and_set_user(&layer->base,
			plane_st->state, plane_st->plane, plane_st->crtc);
	if (IS_ERR(c_st))
		return PTR_ERR(c_st);

	st = to_layer_st(c_st);

	st->rot = dflow->rot;
	st->hsize = kfb->aligned_w;
	st->vsize = kfb->aligned_h;

	for (i = 0; i < fb->format->num_planes; i++)
		st->addr[i] = komeda_fb_get_pixel_addr(kfb, dflow->in_x,
						       dflow->in_y, i);

	err = komeda_component_validate_private(&layer->base, c_st);
	if (err)
		return err;

	/* update the data flow for the next stage */
	komeda_component_set_output(&dflow->input, &layer->base, 0);

	return 0;
}

static void pipeline_composition_size(struct komeda_crtc_state *kcrtc_st,
				      u16 *hsize, u16 *vsize)
{
	struct drm_display_mode *m = &kcrtc_st->base.adjusted_mode;

	if (hsize)
		*hsize = m->hdisplay;
	if (vsize)
		*vsize = m->vdisplay;
}

static int
komeda_compiz_set_input(struct komeda_compiz *compiz,
			struct komeda_crtc_state *kcrtc_st,
			struct komeda_data_flow_cfg *dflow)
{
	struct drm_atomic_state *drm_st = kcrtc_st->base.state;
	struct komeda_component_state *c_st, *old_st;
	struct komeda_compiz_input_cfg *cin;
	u16 compiz_w, compiz_h;
	int idx = dflow->blending_zorder;

	pipeline_composition_size(kcrtc_st, &compiz_w, &compiz_h);
	/* check display rect */
	if ((dflow->out_x + dflow->out_w > compiz_w) ||
	    (dflow->out_y + dflow->out_h > compiz_h) ||
	     dflow->out_w == 0 || dflow->out_h == 0) {
		DRM_DEBUG_ATOMIC("invalid disp rect [x=%d, y=%d, w=%d, h=%d]\n",
				 dflow->out_x, dflow->out_y,
				 dflow->out_w, dflow->out_h);
		return -EINVAL;
	}

	c_st = komeda_component_get_state_and_set_user(&compiz->base, drm_st,
			kcrtc_st->base.crtc, kcrtc_st->base.crtc);
	if (IS_ERR(c_st))
		return PTR_ERR(c_st);

	if (komeda_component_check_input(c_st, &dflow->input, idx))
		return -EINVAL;

	cin = &(to_compiz_st(c_st)->cins[idx]);

	cin->hsize   = dflow->out_w;
	cin->vsize   = dflow->out_h;
	cin->hoffset = dflow->out_x;
	cin->voffset = dflow->out_y;
	cin->pixel_blend_mode = dflow->pixel_blend_mode;
	cin->layer_alpha = dflow->layer_alpha;

	old_st = komeda_component_get_old_state(&compiz->base, drm_st);
	WARN_ON(!old_st);

	/* compare with old to check if this input has been changed */
	if (memcmp(&(to_compiz_st(old_st)->cins[idx]), cin, sizeof(*cin)))
		c_st->changed_active_inputs |= BIT(idx);

	komeda_component_add_input(c_st, &dflow->input, idx);

	return 0;
}

static int
komeda_compiz_validate(struct komeda_compiz *compiz,
		       struct komeda_crtc_state *state,
		       struct komeda_data_flow_cfg *dflow)
{
	struct komeda_component_state *c_st;
	struct komeda_compiz_state *st;

	c_st = komeda_component_get_state_and_set_user(&compiz->base,
			state->base.state, state->base.crtc, state->base.crtc);
	if (IS_ERR(c_st))
		return PTR_ERR(c_st);

	st = to_compiz_st(c_st);

	pipeline_composition_size(state, &st->hsize, &st->vsize);

	komeda_component_set_output(&dflow->input, &compiz->base, 0);

	/* compiz output dflow will be fed to the next pipeline stage, prepare
	 * the data flow configuration for the next stage
	 */
	if (dflow) {
		dflow->in_w = st->hsize;
		dflow->in_h = st->vsize;
		dflow->out_w = dflow->in_w;
		dflow->out_h = dflow->in_h;
		/* the output data of compiz doesn't have alpha, it only can be
		 * used as bottom layer when blend it with master layers
		 */
		dflow->pixel_blend_mode = DRM_MODE_BLEND_PIXEL_NONE;
		dflow->layer_alpha = 0xFF;
		dflow->blending_zorder = 0;
	}

	return 0;
}

static int
komeda_improc_validate(struct komeda_improc *improc,
		       struct komeda_crtc_state *kcrtc_st,
		       struct komeda_data_flow_cfg *dflow)
{
	struct drm_crtc *crtc = kcrtc_st->base.crtc;
	struct komeda_component_state *c_st;
	struct komeda_improc_state *st;

	c_st = komeda_component_get_state_and_set_user(&improc->base,
			kcrtc_st->base.state, crtc, crtc);
	if (IS_ERR(c_st))
		return PTR_ERR(c_st);

	st = to_improc_st(c_st);

	st->hsize = dflow->in_w;
	st->vsize = dflow->in_h;

	komeda_component_add_input(&st->base, &dflow->input, 0);
	komeda_component_set_output(&dflow->input, &improc->base, 0);

	return 0;
}

static int
komeda_timing_ctrlr_validate(struct komeda_timing_ctrlr *ctrlr,
			     struct komeda_crtc_state *kcrtc_st,
			     struct komeda_data_flow_cfg *dflow)
{
	struct drm_crtc *crtc = kcrtc_st->base.crtc;
	struct komeda_timing_ctrlr_state *st;
	struct komeda_component_state *c_st;

	c_st = komeda_component_get_state_and_set_user(&ctrlr->base,
			kcrtc_st->base.state, crtc, crtc);
	if (IS_ERR(c_st))
		return PTR_ERR(c_st);

	st = to_ctrlr_st(c_st);

	komeda_component_add_input(&st->base, &dflow->input, 0);
	komeda_component_set_output(&dflow->input, &ctrlr->base, 0);

	return 0;
}

int komeda_build_layer_data_flow(struct komeda_layer *layer,
				 struct komeda_plane_state *kplane_st,
				 struct komeda_crtc_state *kcrtc_st,
				 struct komeda_data_flow_cfg *dflow)
{
	struct drm_plane *plane = kplane_st->base.plane;
	struct komeda_pipeline *pipe = layer->base.pipeline;
	int err;

	DRM_DEBUG_ATOMIC("%s handling [PLANE:%d:%s]: src[x/y:%d/%d, w/h:%d/%d] disp[x/y:%d/%d, w/h:%d/%d]",
			 layer->base.name, plane->base.id, plane->name,
			 dflow->in_x, dflow->in_y, dflow->in_w, dflow->in_h,
			 dflow->out_x, dflow->out_y, dflow->out_w, dflow->out_h);

	err = komeda_layer_validate(layer, kplane_st, dflow);
	if (err)
		return err;

	err = komeda_compiz_set_input(pipe->compiz, kcrtc_st, dflow);

	return err;
}

/* build display output data flow, the data path is:
 * compiz -> improc -> timing_ctrlr
 */
int komeda_build_display_data_flow(struct komeda_crtc *kcrtc,
				   struct komeda_crtc_state *kcrtc_st)
{
	struct komeda_pipeline *master = kcrtc->master;
	struct komeda_data_flow_cfg m_dflow; /* master data flow */
	int err;

	memset(&m_dflow, 0, sizeof(m_dflow));

	err = komeda_compiz_validate(master->compiz, kcrtc_st, &m_dflow);
	if (err)
		return err;

	err = komeda_improc_validate(master->improc, kcrtc_st, &m_dflow);
	if (err)
		return err;

	err = komeda_timing_ctrlr_validate(master->ctrlr, kcrtc_st, &m_dflow);
	if (err)
		return err;

	return 0;
}

static void
komeda_pipeline_unbound_components(struct komeda_pipeline *pipe,
				   struct komeda_pipeline_state *new)
{
	struct drm_atomic_state *drm_st = new->obj.state;
	struct komeda_pipeline_state *old = priv_to_pipe_st(pipe->obj.state);
	struct komeda_component_state *c_st;
	struct komeda_component *c;
	u32 disabling_comps, id;

	WARN_ON(!old);

	disabling_comps = (~new->active_comps) & old->active_comps;

	/* unbound all disabling component */
	dp_for_each_set_bit(id, disabling_comps) {
		c = komeda_pipeline_get_component(pipe, id);
		c_st = komeda_component_get_state_and_set_user(c,
				drm_st, NULL, new->crtc);
		WARN_ON(IS_ERR(c_st));
	}
}

/* release unclaimed pipeline resource */
int komeda_release_unclaimed_resources(struct komeda_pipeline *pipe,
				       struct komeda_crtc_state *kcrtc_st)
{
	struct drm_atomic_state *drm_st = kcrtc_st->base.state;
	struct komeda_pipeline_state *st;

	/* ignore the pipeline which is not affected */
	if (!pipe || !has_bit(pipe->id, kcrtc_st->affected_pipes))
		return 0;

	if (has_bit(pipe->id, kcrtc_st->active_pipes))
		st = komeda_pipeline_get_new_state(pipe, drm_st);
	else
		st = komeda_pipeline_get_state_and_set_crtc(pipe, drm_st, NULL);

	if (WARN_ON(IS_ERR_OR_NULL(st)))
		return -EINVAL;

	komeda_pipeline_unbound_components(pipe, st);

	return 0;
}

void komeda_pipeline_disable(struct komeda_pipeline *pipe,
			     struct drm_atomic_state *old_state)
{
	struct komeda_pipeline_state *old;
	struct komeda_component *c;
	struct komeda_component_state *c_st;
	u32 id, disabling_comps = 0;

	old = komeda_pipeline_get_old_state(pipe, old_state);

	disabling_comps = old->active_comps;
	DRM_DEBUG_ATOMIC("PIPE%d: disabling_comps: 0x%x.\n",
			 pipe->id, disabling_comps);

	dp_for_each_set_bit(id, disabling_comps) {
		c = komeda_pipeline_get_component(pipe, id);
		c_st = priv_to_comp_st(c->obj.state);

		/*
		 * If we disabled a component then all active_inputs should be
		 * put in the list of changed_active_inputs, so they get
		 * re-enabled.
		 * This usually happens during a modeset when the pipeline is
		 * first disabled and then the actual state gets committed
		 * again.
		 */
		c_st->changed_active_inputs |= c_st->active_inputs;

		c->funcs->disable(c);
	}
}

void komeda_pipeline_update(struct komeda_pipeline *pipe,
			    struct drm_atomic_state *old_state)
{
	struct komeda_pipeline_state *new = priv_to_pipe_st(pipe->obj.state);
	struct komeda_pipeline_state *old;
	struct komeda_component *c;
	u32 id, changed_comps = 0;

	old = komeda_pipeline_get_old_state(pipe, old_state);

	changed_comps = new->active_comps | old->active_comps;

	DRM_DEBUG_ATOMIC("PIPE%d: active_comps: 0x%x, changed: 0x%x.\n",
			 pipe->id, new->active_comps, changed_comps);

	dp_for_each_set_bit(id, changed_comps) {
		c = komeda_pipeline_get_component(pipe, id);

		if (new->active_comps & BIT(c->id))
			c->funcs->update(c, priv_to_comp_st(c->obj.state));
		else
			c->funcs->disable(c);
	}
}