alistair23-linux/drivers/gpu/drm/i915/intel_atomic_plane.c

/*
 * Copyright © 2014 Intel Corporation
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 */

/**
 * DOC: atomic plane helpers
 *
 * The functions here are used by the atomic plane helper functions to
 * implement legacy plane updates (i.e., drm_plane->update_plane() and
 * drm_plane->disable_plane()).  This allows plane updates to use the
 * atomic state infrastructure and perform plane updates as separate
 * prepare/check/commit/cleanup steps.
 */

#include <drm/drmP.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_plane_helper.h>
#include "intel_drv.h"

/**
 * intel_create_plane_state - create plane state object
 * @plane: drm plane
 *
 * Allocates a fresh plane state for the given plane and sets some of
 * the state values to sensible initial values.
 *
 * Returns: A newly allocated plane state, or NULL on failure
 */
struct intel_plane_state *
intel_create_plane_state(struct drm_plane *plane)
{
	struct intel_plane_state *state;

	state = kzalloc(sizeof(*state), GFP_KERNEL);
	if (!state)
		return NULL;

	state->base.plane = plane;
	state->base.rotation = BIT(DRM_ROTATE_0);

	return state;
}

/**
 * intel_plane_duplicate_state - duplicate plane state
 * @plane: drm plane
 *
 * Allocates and returns a copy of the plane state (both common and
 * Intel-specific) for the specified plane.
 *
 * Returns: The newly allocated plane state, or NULL on failure.
 */
struct drm_plane_state *
intel_plane_duplicate_state(struct drm_plane *plane)
{
	struct drm_plane_state *state;
	struct intel_plane_state *intel_state;

	if (WARN_ON(!plane->state))
		intel_state = intel_create_plane_state(plane);
	else
		intel_state = kmemdup(plane->state, sizeof(*intel_state),
				      GFP_KERNEL);

	if (!intel_state)
		return NULL;

	state = &intel_state->base;
	if (state->fb)
		drm_framebuffer_reference(state->fb);

	return state;
}

/**
 * intel_plane_destroy_state - destroy plane state
 * @plane: drm plane
 * @state: state object to destroy
 *
 * Destroys the plane state (both common and Intel-specific) for the
 * specified plane.
 */
void
intel_plane_destroy_state(struct drm_plane *plane,
			  struct drm_plane_state *state)
{
	drm_atomic_helper_plane_destroy_state(plane, state);
}

static int intel_plane_atomic_check(struct drm_plane *plane,
				    struct drm_plane_state *state)
{
	struct drm_crtc *crtc = state->crtc;
	struct intel_crtc *intel_crtc;
	struct intel_plane *intel_plane = to_intel_plane(plane);
	struct intel_plane_state *intel_state = to_intel_plane_state(state);

	crtc = crtc ? crtc : plane->crtc;
	intel_crtc = to_intel_crtc(crtc);

	/*
	 * Both crtc and plane->crtc could be NULL if we're updating a
	 * property while the plane is disabled.  We don't actually have
	 * anything driver-specific we need to test in that case, so
	 * just return success.
	 */
	if (!crtc)
		return 0;

	/*
	 * The original src/dest coordinates are stored in state->base, but
	 * we want to keep another copy internal to our driver that we can
	 * clip/modify ourselves.
	 */
	intel_state->src.x1 = state->src_x;
	intel_state->src.y1 = state->src_y;
	intel_state->src.x2 = state->src_x + state->src_w;
	intel_state->src.y2 = state->src_y + state->src_h;
	intel_state->dst.x1 = state->crtc_x;
	intel_state->dst.y1 = state->crtc_y;
	intel_state->dst.x2 = state->crtc_x + state->crtc_w;
	intel_state->dst.y2 = state->crtc_y + state->crtc_h;

	/* Clip all planes to CRTC size, or 0x0 if CRTC is disabled */
	intel_state->clip.x1 = 0;
	intel_state->clip.y1 = 0;
	intel_state->clip.x2 =
		intel_crtc->active ? intel_crtc->config->pipe_src_w : 0;
	intel_state->clip.y2 =
		intel_crtc->active ? intel_crtc->config->pipe_src_h : 0;

	/*
	 * Disabling a plane is always okay; we just need to update
	 * fb tracking in a special way since cleanup_fb() won't
	 * get called by the plane helpers.
	 */
	if (state->fb == NULL && plane->state->fb != NULL) {
		/*
		 * 'prepare' is never called when plane is being disabled, so
		 * we need to handle frontbuffer tracking as a special case
		 */
		intel_crtc->atomic.disabled_planes |=
			(1 << drm_plane_index(plane));
	}

	return intel_plane->check_plane(plane, intel_state);
}

static void intel_plane_atomic_update(struct drm_plane *plane,
				      struct drm_plane_state *old_state)
{
	struct intel_plane *intel_plane = to_intel_plane(plane);
	struct intel_plane_state *intel_state =
		to_intel_plane_state(plane->state);

	/* Don't disable an already disabled plane */
	if (!plane->state->fb && !old_state->fb)
		return;

	intel_plane->commit_plane(plane, intel_state);
}

const struct drm_plane_helper_funcs intel_plane_helper_funcs = {
	.prepare_fb = intel_prepare_plane_fb,
	.cleanup_fb = intel_cleanup_plane_fb,
	.atomic_check = intel_plane_atomic_check,
	.atomic_update = intel_plane_atomic_update,
};

/**
 * intel_plane_atomic_get_property - fetch plane property value
 * @plane: plane to fetch property for
 * @state: state containing the property value
 * @property: property to look up
 * @val: pointer to write property value into
 *
 * The DRM core does not store shadow copies of properties for
 * atomic-capable drivers.  This entrypoint is used to fetch
 * the current value of a driver-specific plane property.
 */
int
intel_plane_atomic_get_property(struct drm_plane *plane,
				const struct drm_plane_state *state,
				struct drm_property *property,
				uint64_t *val)
{
	struct drm_mode_config *config = &plane->dev->mode_config;

	if (property == config->rotation_property) {
		*val = state->rotation;
	} else {
		DRM_DEBUG_KMS("Unknown plane property '%s'\n", property->name);
		return -EINVAL;
	}

	return 0;
}

/**
 * intel_plane_atomic_set_property - set plane property value
 * @plane: plane to set property for
 * @state: state to update property value in
 * @property: property to set
 * @val: value to set property to
 *
 * Writes the specified property value for a plane into the provided atomic
 * state object.
 *
 * Returns 0 on success, -EINVAL on unrecognized properties
 */
int
intel_plane_atomic_set_property(struct drm_plane *plane,
				struct drm_plane_state *state,
				struct drm_property *property,
				uint64_t val)
{
	struct drm_mode_config *config = &plane->dev->mode_config;

	if (property == config->rotation_property) {
		state->rotation = val;
	} else {
		DRM_DEBUG_KMS("Unknown plane property '%s'\n", property->name);
		return -EINVAL;
	}

	return 0;
}