drivers/gpu/drm/xen/xen_drm_front_kms.c - third_party/linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0 OR MIT

 /*
  *  Xen para-virtual DRM device
  *
  * Copyright (C) 2016-2018 EPAM Systems Inc.
  *
  * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
  */

 #include "xen_drm_front_kms.h"

 #include <drm/drmP.h>
 #include <drm/drm_atomic.h>
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_crtc_helper.h>
 #include <drm/drm_gem.h>
 #include <drm/drm_gem_framebuffer_helper.h>

 #include "xen_drm_front.h"
 #include "xen_drm_front_conn.h"

 /*
  * Timeout in ms to wait for frame done event from the backend:
  * must be a bit more than IO time-out
  */
 #define FRAME_DONE_TO_MS	(XEN_DRM_FRONT_WAIT_BACK_MS + 100)

 static struct xen_drm_front_drm_pipeline *
 to_xen_drm_pipeline(struct drm_simple_display_pipe *pipe)
 {
 	return container_of(pipe, struct xen_drm_front_drm_pipeline, pipe);
 }

 static void fb_destroy(struct drm_framebuffer *fb)
 {
 	struct xen_drm_front_drm_info *drm_info = fb->dev->dev_private;
 	int idx;

 	if (drm_dev_enter(fb->dev, &idx)) {
 		xen_drm_front_fb_detach(drm_info->front_info,
 					xen_drm_front_fb_to_cookie(fb));
 		drm_dev_exit(idx);
 	}
 	drm_gem_fb_destroy(fb);
 }

 static struct drm_framebuffer_funcs fb_funcs = {
 	.destroy = fb_destroy,
 };

 static struct drm_framebuffer *
 fb_create(struct drm_device *dev, struct drm_file *filp,
 	  const struct drm_mode_fb_cmd2 *mode_cmd)
 {
 	struct xen_drm_front_drm_info *drm_info = dev->dev_private;
 	static struct drm_framebuffer *fb;
 	struct drm_gem_object *gem_obj;
 	int ret;

 	fb = drm_gem_fb_create_with_funcs(dev, filp, mode_cmd, &fb_funcs);
 	if (IS_ERR_OR_NULL(fb))
 		return fb;

 	gem_obj = drm_gem_object_lookup(filp, mode_cmd->handles[0]);
 	if (!gem_obj) {
 		DRM_ERROR("Failed to lookup GEM object\n");
 		ret = -ENOENT;
 		goto fail;
 	}

 	drm_gem_object_put_unlocked(gem_obj);

 	ret = xen_drm_front_fb_attach(drm_info->front_info,
 				      xen_drm_front_dbuf_to_cookie(gem_obj),
 				      xen_drm_front_fb_to_cookie(fb),
 				      fb->width, fb->height,
 				      fb->format->format);
 	if (ret < 0) {
 		DRM_ERROR("Back failed to attach FB %p: %d\n", fb, ret);
 		goto fail;
 	}

 	return fb;

 fail:
 	drm_gem_fb_destroy(fb);
 	return ERR_PTR(ret);
 }

 static const struct drm_mode_config_funcs mode_config_funcs = {
 	.fb_create = fb_create,
 	.atomic_check = drm_atomic_helper_check,
 	.atomic_commit = drm_atomic_helper_commit,
 };

 static void send_pending_event(struct xen_drm_front_drm_pipeline *pipeline)
 {
 	struct drm_crtc *crtc = &pipeline->pipe.crtc;
 	struct drm_device *dev = crtc->dev;
 	unsigned long flags;

 	spin_lock_irqsave(&dev->event_lock, flags);
 	if (pipeline->pending_event)
 		drm_crtc_send_vblank_event(crtc, pipeline->pending_event);
 	pipeline->pending_event = NULL;
 	spin_unlock_irqrestore(&dev->event_lock, flags);
 }

 static void display_enable(struct drm_simple_display_pipe *pipe,
 			   struct drm_crtc_state *crtc_state,
 			   struct drm_plane_state *plane_state)
 {
 	struct xen_drm_front_drm_pipeline *pipeline =
 			to_xen_drm_pipeline(pipe);
 	struct drm_crtc *crtc = &pipe->crtc;
 	struct drm_framebuffer *fb = plane_state->fb;
 	int ret, idx;

 	if (!drm_dev_enter(pipe->crtc.dev, &idx))
 		return;

 	ret = xen_drm_front_mode_set(pipeline, crtc->x, crtc->y,
 				     fb->width, fb->height,
 				     fb->format->cpp[0] * 8,
 				     xen_drm_front_fb_to_cookie(fb));

 	if (ret) {
 		DRM_ERROR("Failed to enable display: %d\n", ret);
 		pipeline->conn_connected = false;
 	}

 	drm_dev_exit(idx);
 }

 static void display_disable(struct drm_simple_display_pipe *pipe)
 {
 	struct xen_drm_front_drm_pipeline *pipeline =
 			to_xen_drm_pipeline(pipe);
 	int ret = 0, idx;

 	if (drm_dev_enter(pipe->crtc.dev, &idx)) {
 		ret = xen_drm_front_mode_set(pipeline, 0, 0, 0, 0, 0,
 					     xen_drm_front_fb_to_cookie(NULL));
 		drm_dev_exit(idx);
 	}
 	if (ret)
 		DRM_ERROR("Failed to disable display: %d\n", ret);

 	/* Make sure we can restart with enabled connector next time */
 	pipeline->conn_connected = true;

 	/* release stalled event if any */
 	send_pending_event(pipeline);
 }

 void xen_drm_front_kms_on_frame_done(struct xen_drm_front_drm_pipeline *pipeline,
 				     u64 fb_cookie)
 {
 	/*
 	 * This runs in interrupt context, e.g. under
 	 * drm_info->front_info->io_lock, so we cannot call _sync version
 	 * to cancel the work
 	 */
 	cancel_delayed_work(&pipeline->pflip_to_worker);

 	send_pending_event(pipeline);
 }

 static void pflip_to_worker(struct work_struct *work)
 {
 	struct delayed_work *delayed_work = to_delayed_work(work);
 	struct xen_drm_front_drm_pipeline *pipeline =
 			container_of(delayed_work,
 				     struct xen_drm_front_drm_pipeline,
 				     pflip_to_worker);

 	DRM_ERROR("Frame done timed-out, releasing");
 	send_pending_event(pipeline);
 }

 static bool display_send_page_flip(struct drm_simple_display_pipe *pipe,
 				   struct drm_plane_state *old_plane_state)
 {
 	struct drm_plane_state *plane_state =
 			drm_atomic_get_new_plane_state(old_plane_state->state,
 						       &pipe->plane);

 	/*
 	 * If old_plane_state->fb is NULL and plane_state->fb is not,
 	 * then this is an atomic commit which will enable display.
 	 * If old_plane_state->fb is not NULL and plane_state->fb is,
 	 * then this is an atomic commit which will disable display.
 	 * Ignore these and do not send page flip as this framebuffer will be
 	 * sent to the backend as a part of display_set_config call.
 	 */
 	if (old_plane_state->fb && plane_state->fb) {
 		struct xen_drm_front_drm_pipeline *pipeline =
 				to_xen_drm_pipeline(pipe);
 		struct xen_drm_front_drm_info *drm_info = pipeline->drm_info;
 		int ret;

 		schedule_delayed_work(&pipeline->pflip_to_worker,
 				      msecs_to_jiffies(FRAME_DONE_TO_MS));

 		ret = xen_drm_front_page_flip(drm_info->front_info,
 					      pipeline->index,
 					      xen_drm_front_fb_to_cookie(plane_state->fb));
 		if (ret) {
 			DRM_ERROR("Failed to send page flip request to backend: %d\n", ret);

 			pipeline->conn_connected = false;
 			/*
 			 * Report the flip not handled, so pending event is
 			 * sent, unblocking user-space.
 			 */
 			return false;
 		}
 		/*
 		 * Signal that page flip was handled, pending event will be sent
 		 * on frame done event from the backend.
 		 */
 		return true;
 	}

 	return false;
 }

 static void display_update(struct drm_simple_display_pipe *pipe,
 			   struct drm_plane_state *old_plane_state)
 {
 	struct xen_drm_front_drm_pipeline *pipeline =
 			to_xen_drm_pipeline(pipe);
 	struct drm_crtc *crtc = &pipe->crtc;
 	struct drm_pending_vblank_event *event;
 	int idx;

 	event = crtc->state->event;
 	if (event) {
 		struct drm_device *dev = crtc->dev;
 		unsigned long flags;

 		WARN_ON(pipeline->pending_event);

 		spin_lock_irqsave(&dev->event_lock, flags);
 		crtc->state->event = NULL;

 		pipeline->pending_event = event;
 		spin_unlock_irqrestore(&dev->event_lock, flags);
 	}

 	if (!drm_dev_enter(pipe->crtc.dev, &idx)) {
 		send_pending_event(pipeline);
 		return;
 	}

 	/*
 	 * Send page flip request to the backend *after* we have event cached
 	 * above, so on page flip done event from the backend we can
 	 * deliver it and there is no race condition between this code and
 	 * event from the backend.
 	 * If this is not a page flip, e.g. no flip done event from the backend
 	 * is expected, then send now.
 	 */
 	if (!display_send_page_flip(pipe, old_plane_state))
 		send_pending_event(pipeline);

 	drm_dev_exit(idx);
 }

 static enum drm_mode_status
 display_mode_valid(struct drm_crtc *crtc, const struct drm_display_mode *mode)
 {
 	struct xen_drm_front_drm_pipeline *pipeline =
 			container_of(crtc, struct xen_drm_front_drm_pipeline,
 				     pipe.crtc);

 	if (mode->hdisplay != pipeline->width)
 		return MODE_ERROR;

 	if (mode->vdisplay != pipeline->height)
 		return MODE_ERROR;

 	return MODE_OK;
 }

 static const struct drm_simple_display_pipe_funcs display_funcs = {
 	.mode_valid = display_mode_valid,
 	.enable = display_enable,
 	.disable = display_disable,
 	.prepare_fb = drm_gem_fb_simple_display_pipe_prepare_fb,
 	.update = display_update,
 };

 static int display_pipe_init(struct xen_drm_front_drm_info *drm_info,
 			     int index, struct xen_drm_front_cfg_connector *cfg,
 			     struct xen_drm_front_drm_pipeline *pipeline)
 {
 	struct drm_device *dev = drm_info->drm_dev;
 	const u32 *formats;
 	int format_count;
 	int ret;

 	pipeline->drm_info = drm_info;
 	pipeline->index = index;
 	pipeline->height = cfg->height;
 	pipeline->width = cfg->width;

 	INIT_DELAYED_WORK(&pipeline->pflip_to_worker, pflip_to_worker);

 	ret = xen_drm_front_conn_init(drm_info, &pipeline->conn);
 	if (ret)
 		return ret;

 	formats = xen_drm_front_conn_get_formats(&format_count);

 	return drm_simple_display_pipe_init(dev, &pipeline->pipe,
 					    &display_funcs, formats,
 					    format_count, NULL,
 					    &pipeline->conn);
 }

 int xen_drm_front_kms_init(struct xen_drm_front_drm_info *drm_info)
 {
 	struct drm_device *dev = drm_info->drm_dev;
 	int i, 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 = &mode_config_funcs;

 	for (i = 0; i < drm_info->front_info->cfg.num_connectors; i++) {
 		struct xen_drm_front_cfg_connector *cfg =
 				&drm_info->front_info->cfg.connectors[i];
 		struct xen_drm_front_drm_pipeline *pipeline =
 				&drm_info->pipeline[i];

 		ret = display_pipe_init(drm_info, i, cfg, pipeline);
 		if (ret) {
 			drm_mode_config_cleanup(dev);
 			return ret;
 		}
 	}

 	drm_mode_config_reset(dev);
 	drm_kms_helper_poll_init(dev);
 	return 0;
 }

 void xen_drm_front_kms_fini(struct xen_drm_front_drm_info *drm_info)
 {
 	int i;

 	for (i = 0; i < drm_info->front_info->cfg.num_connectors; i++) {
 		struct xen_drm_front_drm_pipeline *pipeline =
 				&drm_info->pipeline[i];

 		cancel_delayed_work_sync(&pipeline->pflip_to_worker);

 		send_pending_event(pipeline);
 	}
 }
	// SPDX-License-Identifier: GPL-2.0 OR MIT

	/*
	* Xen para-virtual DRM device
	*
	* Copyright (C) 2016-2018 EPAM Systems Inc.
	*
	* Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
	*/

	#include "xen_drm_front_kms.h"

	#include <drm/drmP.h>
	#include <drm/drm_atomic.h>
	#include <drm/drm_atomic_helper.h>
	#include <drm/drm_crtc_helper.h>
	#include <drm/drm_gem.h>
	#include <drm/drm_gem_framebuffer_helper.h>

	#include "xen_drm_front.h"
	#include "xen_drm_front_conn.h"

	/*
	* Timeout in ms to wait for frame done event from the backend:
	* must be a bit more than IO time-out
	*/
	#define FRAME_DONE_TO_MS (XEN_DRM_FRONT_WAIT_BACK_MS + 100)

	static struct xen_drm_front_drm_pipeline *
	to_xen_drm_pipeline(struct drm_simple_display_pipe *pipe)
	{
	return container_of(pipe, struct xen_drm_front_drm_pipeline, pipe);
	}

	static void fb_destroy(struct drm_framebuffer *fb)
	{
	struct xen_drm_front_drm_info *drm_info = fb->dev->dev_private;
	int idx;

	if (drm_dev_enter(fb->dev, &idx)) {
	xen_drm_front_fb_detach(drm_info->front_info,
	xen_drm_front_fb_to_cookie(fb));
	drm_dev_exit(idx);
	}
	drm_gem_fb_destroy(fb);
	}

	static struct drm_framebuffer_funcs fb_funcs = {
	.destroy = fb_destroy,
	};

	static struct drm_framebuffer *
	fb_create(struct drm_device dev, struct drm_file filp,
	const struct drm_mode_fb_cmd2 *mode_cmd)
	{
	struct xen_drm_front_drm_info *drm_info = dev->dev_private;
	static struct drm_framebuffer *fb;
	struct drm_gem_object *gem_obj;
	int ret;

	fb = drm_gem_fb_create_with_funcs(dev, filp, mode_cmd, &fb_funcs);
	if (IS_ERR_OR_NULL(fb))
	return fb;

	gem_obj = drm_gem_object_lookup(filp, mode_cmd->handles[0]);
	if (!gem_obj) {
	DRM_ERROR("Failed to lookup GEM object\n");
	ret = -ENOENT;
	goto fail;
	}

	drm_gem_object_put_unlocked(gem_obj);

	ret = xen_drm_front_fb_attach(drm_info->front_info,
	xen_drm_front_dbuf_to_cookie(gem_obj),
	xen_drm_front_fb_to_cookie(fb),
	fb->width, fb->height,
	fb->format->format);
	if (ret < 0) {
	DRM_ERROR("Back failed to attach FB %p: %d\n", fb, ret);
	goto fail;
	}

	return fb;

	fail:
	drm_gem_fb_destroy(fb);
	return ERR_PTR(ret);
	}

	static const struct drm_mode_config_funcs mode_config_funcs = {
	.fb_create = fb_create,
	.atomic_check = drm_atomic_helper_check,
	.atomic_commit = drm_atomic_helper_commit,
	};

	static void send_pending_event(struct xen_drm_front_drm_pipeline *pipeline)
	{
	struct drm_crtc *crtc = &pipeline->pipe.crtc;
	struct drm_device *dev = crtc->dev;
	unsigned long flags;

	spin_lock_irqsave(&dev->event_lock, flags);
	if (pipeline->pending_event)
	drm_crtc_send_vblank_event(crtc, pipeline->pending_event);
	pipeline->pending_event = NULL;
	spin_unlock_irqrestore(&dev->event_lock, flags);
	}

	static void display_enable(struct drm_simple_display_pipe *pipe,
	struct drm_crtc_state *crtc_state,
	struct drm_plane_state *plane_state)
	{
	struct xen_drm_front_drm_pipeline *pipeline =
	to_xen_drm_pipeline(pipe);
	struct drm_crtc *crtc = &pipe->crtc;
	struct drm_framebuffer *fb = plane_state->fb;
	int ret, idx;

	if (!drm_dev_enter(pipe->crtc.dev, &idx))
	return;

	ret = xen_drm_front_mode_set(pipeline, crtc->x, crtc->y,
	fb->width, fb->height,
	fb->format->cpp[0] * 8,
	xen_drm_front_fb_to_cookie(fb));

	if (ret) {
	DRM_ERROR("Failed to enable display: %d\n", ret);
	pipeline->conn_connected = false;
	}

	drm_dev_exit(idx);
	}

	static void display_disable(struct drm_simple_display_pipe *pipe)
	{
	struct xen_drm_front_drm_pipeline *pipeline =
	to_xen_drm_pipeline(pipe);
	int ret = 0, idx;

	if (drm_dev_enter(pipe->crtc.dev, &idx)) {
	ret = xen_drm_front_mode_set(pipeline, 0, 0, 0, 0, 0,
	xen_drm_front_fb_to_cookie(NULL));
	drm_dev_exit(idx);
	}
	if (ret)
	DRM_ERROR("Failed to disable display: %d\n", ret);

	/* Make sure we can restart with enabled connector next time */
	pipeline->conn_connected = true;

	/* release stalled event if any */
	send_pending_event(pipeline);
	}

	void xen_drm_front_kms_on_frame_done(struct xen_drm_front_drm_pipeline *pipeline,
	u64 fb_cookie)
	{
	/*
	* This runs in interrupt context, e.g. under
	* drm_info->front_info->io_lock, so we cannot call _sync version
	* to cancel the work
	*/
	cancel_delayed_work(&pipeline->pflip_to_worker);

	send_pending_event(pipeline);
	}

	static void pflip_to_worker(struct work_struct *work)
	{
	struct delayed_work *delayed_work = to_delayed_work(work);
	struct xen_drm_front_drm_pipeline *pipeline =
	container_of(delayed_work,
	struct xen_drm_front_drm_pipeline,
	pflip_to_worker);

	DRM_ERROR("Frame done timed-out, releasing");
	send_pending_event(pipeline);
	}

	static bool display_send_page_flip(struct drm_simple_display_pipe *pipe,
	struct drm_plane_state *old_plane_state)
	{
	struct drm_plane_state *plane_state =
	drm_atomic_get_new_plane_state(old_plane_state->state,
	&pipe->plane);

	/*
	* If old_plane_state->fb is NULL and plane_state->fb is not,
	* then this is an atomic commit which will enable display.
	* If old_plane_state->fb is not NULL and plane_state->fb is,
	* then this is an atomic commit which will disable display.
	* Ignore these and do not send page flip as this framebuffer will be
	* sent to the backend as a part of display_set_config call.
	*/
	if (old_plane_state->fb && plane_state->fb) {
	struct xen_drm_front_drm_pipeline *pipeline =
	to_xen_drm_pipeline(pipe);
	struct xen_drm_front_drm_info *drm_info = pipeline->drm_info;
	int ret;

	schedule_delayed_work(&pipeline->pflip_to_worker,
	msecs_to_jiffies(FRAME_DONE_TO_MS));

	ret = xen_drm_front_page_flip(drm_info->front_info,
	pipeline->index,
	xen_drm_front_fb_to_cookie(plane_state->fb));
	if (ret) {
	DRM_ERROR("Failed to send page flip request to backend: %d\n", ret);

	pipeline->conn_connected = false;
	/*
	* Report the flip not handled, so pending event is
	* sent, unblocking user-space.
	*/
	return false;
	}
	/*
	* Signal that page flip was handled, pending event will be sent
	* on frame done event from the backend.
	*/
	return true;
	}

	return false;
	}

	static void display_update(struct drm_simple_display_pipe *pipe,
	struct drm_plane_state *old_plane_state)
	{
	struct xen_drm_front_drm_pipeline *pipeline =
	to_xen_drm_pipeline(pipe);
	struct drm_crtc *crtc = &pipe->crtc;
	struct drm_pending_vblank_event *event;
	int idx;

	event = crtc->state->event;
	if (event) {
	struct drm_device *dev = crtc->dev;
	unsigned long flags;

	WARN_ON(pipeline->pending_event);

	spin_lock_irqsave(&dev->event_lock, flags);
	crtc->state->event = NULL;

	pipeline->pending_event = event;
	spin_unlock_irqrestore(&dev->event_lock, flags);
	}

	if (!drm_dev_enter(pipe->crtc.dev, &idx)) {
	send_pending_event(pipeline);
	return;
	}

	/*
	* Send page flip request to the backend after we have event cached
	* above, so on page flip done event from the backend we can
	* deliver it and there is no race condition between this code and
	* event from the backend.
	* If this is not a page flip, e.g. no flip done event from the backend
	* is expected, then send now.
	*/
	if (!display_send_page_flip(pipe, old_plane_state))
	send_pending_event(pipeline);

	drm_dev_exit(idx);
	}

	static enum drm_mode_status
	display_mode_valid(struct drm_crtc crtc, const struct drm_display_mode mode)
	{
	struct xen_drm_front_drm_pipeline *pipeline =
	container_of(crtc, struct xen_drm_front_drm_pipeline,
	pipe.crtc);

	if (mode->hdisplay != pipeline->width)
	return MODE_ERROR;

	if (mode->vdisplay != pipeline->height)
	return MODE_ERROR;

	return MODE_OK;
	}

	static const struct drm_simple_display_pipe_funcs display_funcs = {
	.mode_valid = display_mode_valid,
	.enable = display_enable,
	.disable = display_disable,
	.prepare_fb = drm_gem_fb_simple_display_pipe_prepare_fb,
	.update = display_update,
	};

	static int display_pipe_init(struct xen_drm_front_drm_info *drm_info,
	int index, struct xen_drm_front_cfg_connector *cfg,
	struct xen_drm_front_drm_pipeline *pipeline)
	{
	struct drm_device *dev = drm_info->drm_dev;
	const u32 *formats;
	int format_count;
	int ret;

	pipeline->drm_info = drm_info;
	pipeline->index = index;
	pipeline->height = cfg->height;
	pipeline->width = cfg->width;

	INIT_DELAYED_WORK(&pipeline->pflip_to_worker, pflip_to_worker);

	ret = xen_drm_front_conn_init(drm_info, &pipeline->conn);
	if (ret)
	return ret;

	formats = xen_drm_front_conn_get_formats(&format_count);

	return drm_simple_display_pipe_init(dev, &pipeline->pipe,
	&display_funcs, formats,
	format_count, NULL,
	&pipeline->conn);
	}

	int xen_drm_front_kms_init(struct xen_drm_front_drm_info *drm_info)
	{
	struct drm_device *dev = drm_info->drm_dev;
	int i, 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 = &mode_config_funcs;

	for (i = 0; i < drm_info->front_info->cfg.num_connectors; i++) {
	struct xen_drm_front_cfg_connector *cfg =
	&drm_info->front_info->cfg.connectors[i];
	struct xen_drm_front_drm_pipeline *pipeline =
	&drm_info->pipeline[i];

	ret = display_pipe_init(drm_info, i, cfg, pipeline);
	if (ret) {
	drm_mode_config_cleanup(dev);
	return ret;
	}
	}

	drm_mode_config_reset(dev);
	drm_kms_helper_poll_init(dev);
	return 0;
	}

	void xen_drm_front_kms_fini(struct xen_drm_front_drm_info *drm_info)
	{
	int i;

	for (i = 0; i < drm_info->front_info->cfg.num_connectors; i++) {
	struct xen_drm_front_drm_pipeline *pipeline =
	&drm_info->pipeline[i];

	cancel_delayed_work_sync(&pipeline->pflip_to_worker);

	send_pending_event(pipeline);
	}
	}