1 files changed, 304 insertions, 0 deletions
diff --git a/drivers/gpu/drm/vkms/vkms_crtc.c b/drivers/gpu/drm/vkms/vkms_crtc.c
new file mode 100644
index 000000000..61e500b8c
--- /dev/null
+++ b/drivers/gpu/drm/vkms/vkms_crtc.c
@@ -0,0 +1,304 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+#include <linux/dma-fence.h>
+
+#include <drm/drm_atomic.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_probe_helper.h>
+#include <drm/drm_vblank.h>
+
+#include "vkms_drv.h"
+
+static enum hrtimer_restart vkms_vblank_simulate(struct hrtimer *timer)
+{
+	struct vkms_output *output = container_of(timer, struct vkms_output,
+						  vblank_hrtimer);
+	struct drm_crtc *crtc = &output->crtc;
+	struct vkms_crtc_state *state;
+	u64 ret_overrun;
+	bool ret, fence_cookie;
+
+	fence_cookie = dma_fence_begin_signalling();
+
+	ret_overrun = hrtimer_forward_now(&output->vblank_hrtimer,
+					  output->period_ns);
+	if (ret_overrun != 1)
+		pr_warn("%s: vblank timer overrun\n", __func__);
+
+	spin_lock(&output->lock);
+	ret = drm_crtc_handle_vblank(crtc);
+	if (!ret)
+		DRM_ERROR("vkms failure on handling vblank");
+
+	state = output->composer_state;
+	spin_unlock(&output->lock);
+
+	if (state && output->composer_enabled) {
+		u64 frame = drm_crtc_accurate_vblank_count(crtc);
+
+		/* update frame_start only if a queued vkms_composer_worker()
+		 * has read the data
+		 */
+		spin_lock(&output->composer_lock);
+		if (!state->crc_pending)
+			state->frame_start = frame;
+		else
+			DRM_DEBUG_DRIVER("crc worker falling behind, frame_start: %llu, frame_end: %llu\n",
+					 state->frame_start, frame);
+		state->frame_end = frame;
+		state->crc_pending = true;
+		spin_unlock(&output->composer_lock);
+
+		ret = queue_work(output->composer_workq, &state->composer_work);
+		if (!ret)
+			DRM_DEBUG_DRIVER("Composer worker already queued\n");
+	}
+
+	dma_fence_end_signalling(fence_cookie);
+
+	return HRTIMER_RESTART;
+}
+
+static int vkms_enable_vblank(struct drm_crtc *crtc)
+{
+	struct drm_device *dev = crtc->dev;
+	unsigned int pipe = drm_crtc_index(crtc);
+	struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
+	struct vkms_output *out = drm_crtc_to_vkms_output(crtc);
+
+	drm_calc_timestamping_constants(crtc, &crtc->mode);
+
+	hrtimer_init(&out->vblank_hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	out->vblank_hrtimer.function = &vkms_vblank_simulate;
+	out->period_ns = ktime_set(0, vblank->framedur_ns);
+	hrtimer_start(&out->vblank_hrtimer, out->period_ns, HRTIMER_MODE_REL);
+
+	return 0;
+}
+
+static void vkms_disable_vblank(struct drm_crtc *crtc)
+{
+	struct vkms_output *out = drm_crtc_to_vkms_output(crtc);
+
+	hrtimer_cancel(&out->vblank_hrtimer);
+}
+
+static bool vkms_get_vblank_timestamp(struct drm_crtc *crtc,
+				      int *max_error, ktime_t *vblank_time,
+				      bool in_vblank_irq)
+{
+	struct drm_device *dev = crtc->dev;
+	unsigned int pipe = crtc->index;
+	struct vkms_device *vkmsdev = drm_device_to_vkms_device(dev);
+	struct vkms_output *output = &vkmsdev->output;
+	struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
+
+	if (!READ_ONCE(vblank->enabled)) {
+		*vblank_time = ktime_get();
+		return true;
+	}
+
+	*vblank_time = READ_ONCE(output->vblank_hrtimer.node.expires);
+
+	if (WARN_ON(*vblank_time == vblank->time))
+		return true;
+
+	/*
+	 * To prevent races we roll the hrtimer forward before we do any
+	 * interrupt processing - this is how real hw works (the interrupt is
+	 * only generated after all the vblank registers are updated) and what
+	 * the vblank core expects. Therefore we need to always correct the
+	 * timestampe by one frame.
+	 */
+	*vblank_time -= output->period_ns;
+
+	return true;
+}
+
+static struct drm_crtc_state *
+vkms_atomic_crtc_duplicate_state(struct drm_crtc *crtc)
+{
+	struct vkms_crtc_state *vkms_state;
+
+	if (WARN_ON(!crtc->state))
+		return NULL;
+
+	vkms_state = kzalloc(sizeof(*vkms_state), GFP_KERNEL);
+	if (!vkms_state)
+		return NULL;
+
+	__drm_atomic_helper_crtc_duplicate_state(crtc, &vkms_state->base);
+
+	INIT_WORK(&vkms_state->composer_work, vkms_composer_worker);
+
+	return &vkms_state->base;
+}
+
+static void vkms_atomic_crtc_destroy_state(struct drm_crtc *crtc,
+					   struct drm_crtc_state *state)
+{
+	struct vkms_crtc_state *vkms_state = to_vkms_crtc_state(state);
+
+	__drm_atomic_helper_crtc_destroy_state(state);
+
+	WARN_ON(work_pending(&vkms_state->composer_work));
+	kfree(vkms_state->active_planes);
+	kfree(vkms_state);
+}
+
+static void vkms_atomic_crtc_reset(struct drm_crtc *crtc)
+{
+	struct vkms_crtc_state *vkms_state =
+		kzalloc(sizeof(*vkms_state), GFP_KERNEL);
+
+	if (crtc->state)
+		vkms_atomic_crtc_destroy_state(crtc, crtc->state);
+
+	__drm_atomic_helper_crtc_reset(crtc, &vkms_state->base);
+	if (vkms_state)
+		INIT_WORK(&vkms_state->composer_work, vkms_composer_worker);
+}
+
+static const struct drm_crtc_funcs vkms_crtc_funcs = {
+	.set_config             = drm_atomic_helper_set_config,
+	.page_flip              = drm_atomic_helper_page_flip,
+	.reset                  = vkms_atomic_crtc_reset,
+	.atomic_duplicate_state = vkms_atomic_crtc_duplicate_state,
+	.atomic_destroy_state   = vkms_atomic_crtc_destroy_state,
+	.enable_vblank		= vkms_enable_vblank,
+	.disable_vblank		= vkms_disable_vblank,
+	.get_vblank_timestamp	= vkms_get_vblank_timestamp,
+	.get_crc_sources	= vkms_get_crc_sources,
+	.set_crc_source		= vkms_set_crc_source,
+	.verify_crc_source	= vkms_verify_crc_source,
+};
+
+static int vkms_crtc_atomic_check(struct drm_crtc *crtc,
+				  struct drm_atomic_state *state)
+{
+	struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(state,
+									  crtc);
+	struct vkms_crtc_state *vkms_state = to_vkms_crtc_state(crtc_state);
+	struct drm_plane *plane;
+	struct drm_plane_state *plane_state;
+	int i = 0, ret;
+
+	if (vkms_state->active_planes)
+		return 0;
+
+	ret = drm_atomic_add_affected_planes(crtc_state->state, crtc);
+	if (ret < 0)
+		return ret;
+
+	drm_for_each_plane_mask(plane, crtc->dev, crtc_state->plane_mask) {
+		plane_state = drm_atomic_get_existing_plane_state(crtc_state->state,
+								  plane);
+		WARN_ON(!plane_state);
+
+		if (!plane_state->visible)
+			continue;
+
+		i++;
+	}
+
+	vkms_state->active_planes = kcalloc(i, sizeof(plane), GFP_KERNEL);
+	if (!vkms_state->active_planes)
+		return -ENOMEM;
+	vkms_state->num_active_planes = i;
+
+	i = 0;
+	drm_for_each_plane_mask(plane, crtc->dev, crtc_state->plane_mask) {
+		plane_state = drm_atomic_get_existing_plane_state(crtc_state->state,
+								  plane);
+
+		if (!plane_state->visible)
+			continue;
+
+		vkms_state->active_planes[i++] =
+			to_vkms_plane_state(plane_state);
+	}
+
+	return 0;
+}
+
+static void vkms_crtc_atomic_enable(struct drm_crtc *crtc,
+				    struct drm_atomic_state *state)
+{
+	drm_crtc_vblank_on(crtc);
+}
+
+static void vkms_crtc_atomic_disable(struct drm_crtc *crtc,
+				     struct drm_atomic_state *state)
+{
+	drm_crtc_vblank_off(crtc);
+}
+
+static void vkms_crtc_atomic_begin(struct drm_crtc *crtc,
+				   struct drm_atomic_state *state)
+{
+	struct vkms_output *vkms_output = drm_crtc_to_vkms_output(crtc);
+
+	/* This lock is held across the atomic commit to block vblank timer
+	 * from scheduling vkms_composer_worker until the composer is updated
+	 */
+	spin_lock_irq(&vkms_output->lock);
+}
+
+static void vkms_crtc_atomic_flush(struct drm_crtc *crtc,
+				   struct drm_atomic_state *state)
+{
+	struct vkms_output *vkms_output = drm_crtc_to_vkms_output(crtc);
+
+	if (crtc->state->event) {
+		spin_lock(&crtc->dev->event_lock);
+
+		if (drm_crtc_vblank_get(crtc) != 0)
+			drm_crtc_send_vblank_event(crtc, crtc->state->event);
+		else
+			drm_crtc_arm_vblank_event(crtc, crtc->state->event);
+
+		spin_unlock(&crtc->dev->event_lock);
+
+		crtc->state->event = NULL;
+	}
+
+	vkms_output->composer_state = to_vkms_crtc_state(crtc->state);
+
+	spin_unlock_irq(&vkms_output->lock);
+}
+
+static const struct drm_crtc_helper_funcs vkms_crtc_helper_funcs = {
+	.atomic_check	= vkms_crtc_atomic_check,
+	.atomic_begin	= vkms_crtc_atomic_begin,
+	.atomic_flush	= vkms_crtc_atomic_flush,
+	.atomic_enable	= vkms_crtc_atomic_enable,
+	.atomic_disable	= vkms_crtc_atomic_disable,
+};
+
+int vkms_crtc_init(struct drm_device *dev, struct drm_crtc *crtc,
+		   struct drm_plane *primary, struct drm_plane *cursor)
+{
+	struct vkms_output *vkms_out = drm_crtc_to_vkms_output(crtc);
+	int ret;
+
+	ret = drmm_crtc_init_with_planes(dev, crtc, primary, cursor,
+					 &vkms_crtc_funcs, NULL);
+	if (ret) {
+		DRM_ERROR("Failed to init CRTC\n");
+		return ret;
+	}
+
+	drm_crtc_helper_add(crtc, &vkms_crtc_helper_funcs);
+
+	drm_mode_crtc_set_gamma_size(crtc, VKMS_LUT_SIZE);
+	drm_crtc_enable_color_mgmt(crtc, 0, false, VKMS_LUT_SIZE);
+
+	spin_lock_init(&vkms_out->lock);
+	spin_lock_init(&vkms_out->composer_lock);
+
+	vkms_out->composer_workq = alloc_ordered_workqueue("vkms_composer", 0);
+	if (!vkms_out->composer_workq)
+		return -ENOMEM;
+
+	return ret;
+}