[PATCH 3/3] drm: Add CRTC_GET_SEQUENCE and CRTC_QUEUE_SEQUENCE ioctls [v2]
From: Keith Packard
Date: Tue Aug 01 2017 - 01:03:34 EST
These provide crtc-id based functions instead of pipe-number, while
also offering higher resolution time (ns) and wider frame count (64)
as required by the Vulkan API.
v2:
* Check for DRIVER_MODESET in new crtc-based vblank ioctls
Failing to check this will oops the driver.
* Ensure vblank interupt is running in crtc_get_sequence ioctl
The sequence and timing values are not correct while the
interrupt is off, so make sure it's running before asking for
them.
* Short-circuit get_sequence if the counter is enabled and accurate
Steal the idea from the code in wait_vblank to avoid the
expense of drm_vblank_get/put
* Return active state of crtc in crtc_get_sequence ioctl
Might be useful for applications that aren't in charge of
modesetting?
* Use drm_crtc_vblank_get/put in new crtc-based vblank sequence ioctls
Daniel Vetter prefers these over the old drm_vblank_put/get
APIs.
* Return s64 ns instead of u64 in new sequence event
Suggested-by: Daniel Vetter <daniel@xxxxxxxx>
Suggested-by: Ville SyrjÃlà <ville.syrjala@xxxxxxxxxxxxxxx>
Signed-off-by: Keith Packard <keithp@xxxxxxxxxx>
---
drivers/gpu/drm/drm_internal.h | 6 ++
drivers/gpu/drm/drm_ioctl.c | 2 +
drivers/gpu/drm/drm_vblank.c | 173 +++++++++++++++++++++++++++++++++++++++++
include/drm/drm_vblank.h | 1 +
include/uapi/drm/drm.h | 32 ++++++++
5 files changed, 214 insertions(+)
diff --git a/drivers/gpu/drm/drm_internal.h b/drivers/gpu/drm/drm_internal.h
index 5cecc974d2f9..b68a193b7907 100644
--- a/drivers/gpu/drm/drm_internal.h
+++ b/drivers/gpu/drm/drm_internal.h
@@ -65,6 +65,12 @@ int drm_legacy_irq_control(struct drm_device *dev, void *data,
int drm_legacy_modeset_ctl(struct drm_device *dev, void *data,
struct drm_file *file_priv);
+int drm_crtc_get_sequence_ioctl(struct drm_device *dev, void *data,
+ struct drm_file *filp);
+
+int drm_crtc_queue_sequence_ioctl(struct drm_device *dev, void *data,
+ struct drm_file *filp);
+
/* drm_auth.c */
int drm_getmagic(struct drm_device *dev, void *data,
struct drm_file *file_priv);
diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c
index f1e568176da9..63016cf3e224 100644
--- a/drivers/gpu/drm/drm_ioctl.c
+++ b/drivers/gpu/drm/drm_ioctl.c
@@ -657,6 +657,8 @@ static const struct drm_ioctl_desc drm_ioctls[] = {
DRM_UNLOCKED|DRM_RENDER_ALLOW),
DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_FD_TO_HANDLE, drm_syncobj_fd_to_handle_ioctl,
DRM_UNLOCKED|DRM_RENDER_ALLOW),
+ DRM_IOCTL_DEF(DRM_IOCTL_CRTC_GET_SEQUENCE, drm_crtc_get_sequence_ioctl, DRM_UNLOCKED),
+ DRM_IOCTL_DEF(DRM_IOCTL_CRTC_QUEUE_SEQUENCE, drm_crtc_queue_sequence_ioctl, DRM_UNLOCKED),
};
#define DRM_CORE_IOCTL_COUNT ARRAY_SIZE( drm_ioctls )
diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c
index 7e7119a5ada3..69b8c92cdd3a 100644
--- a/drivers/gpu/drm/drm_vblank.c
+++ b/drivers/gpu/drm/drm_vblank.c
@@ -812,6 +812,11 @@ static void send_vblank_event(struct drm_device *dev,
e->event.vbl.tv_sec = tv.tv_sec;
e->event.vbl.tv_usec = tv.tv_usec;
break;
+ case DRM_EVENT_CRTC_SEQUENCE:
+ if (seq)
+ e->event.seq.sequence = seq;
+ e->event.seq.time_ns = ktime_to_ns(now);
+ break;
}
trace_drm_vblank_event_delivered(e->base.file_priv, e->pipe, seq);
drm_send_event_locked(dev, &e->base);
@@ -1682,3 +1687,171 @@ bool drm_crtc_handle_vblank(struct drm_crtc *crtc)
return drm_handle_vblank(crtc->dev, drm_crtc_index(crtc));
}
EXPORT_SYMBOL(drm_crtc_handle_vblank);
+
+/*
+ * Get crtc VBLANK count.
+ *
+ * \param dev DRM device
+ * \param data user arguement, pointing to a drm_crtc_get_sequence structure.
+ * \param file_priv drm file private for the user's open file descriptor
+ */
+
+int drm_crtc_get_sequence_ioctl(struct drm_device *dev, void *data,
+ struct drm_file *file_priv)
+{
+ struct drm_crtc *crtc;
+ struct drm_vblank_crtc *vblank;
+ int pipe;
+ struct drm_crtc_get_sequence *get_seq = data;
+ ktime_t now;
+ bool vblank_enabled;
+ int ret;
+
+ if (!drm_core_check_feature(dev, DRIVER_MODESET))
+ return -EINVAL;
+
+ if (!dev->irq_enabled)
+ return -EINVAL;
+
+ crtc = drm_crtc_find(dev, get_seq->crtc_id);
+ if (!crtc)
+ return -ENOENT;
+
+ pipe = drm_crtc_index(crtc);
+
+ vblank = &dev->vblank[pipe];
+ vblank_enabled = dev->vblank_disable_immediate && READ_ONCE(vblank->enabled);
+
+ if (!vblank_enabled) {
+ ret = drm_crtc_vblank_get(crtc);
+ if (ret) {
+ DRM_DEBUG("crtc %d failed to acquire vblank counter, %d\n", pipe, ret);
+ return ret;
+ }
+ }
+ drm_modeset_lock(&crtc->mutex, NULL);
+ if (crtc->state)
+ get_seq->active = crtc->state->enable;
+ else
+ get_seq->active = crtc->enabled;
+ drm_modeset_unlock(&crtc->mutex);
+ get_seq->sequence = drm_vblank_count_and_time(dev, pipe, &now);
+ get_seq->sequence_ns = ktime_to_ns(now);
+ if (!vblank_enabled)
+ drm_crtc_vblank_put(crtc);
+ return 0;
+}
+
+/*
+ * Queue a event for VBLANK sequence
+ *
+ * \param dev DRM device
+ * \param data user arguement, pointing to a drm_crtc_queue_sequence structure.
+ * \param file_priv drm file private for the user's open file descriptor
+ */
+
+int drm_crtc_queue_sequence_ioctl(struct drm_device *dev, void *data,
+ struct drm_file *file_priv)
+{
+ struct drm_crtc *crtc;
+ struct drm_vblank_crtc *vblank;
+ int pipe;
+ struct drm_crtc_queue_sequence *queue_seq = data;
+ ktime_t now;
+ struct drm_pending_vblank_event *e;
+ u32 flags;
+ u64 seq;
+ u64 req_seq;
+ int ret;
+ unsigned long spin_flags;
+
+ if (!drm_core_check_feature(dev, DRIVER_MODESET))
+ return -EINVAL;
+
+ if (!dev->irq_enabled)
+ return -EINVAL;
+
+ crtc = drm_crtc_find(dev, queue_seq->crtc_id);
+ if (!crtc)
+ return -ENOENT;
+
+ flags = queue_seq->flags;
+ /* Check valid flag bits */
+ if (flags & ~(DRM_CRTC_SEQUENCE_RELATIVE|
+ DRM_CRTC_SEQUENCE_NEXT_ON_MISS|
+ DRM_CRTC_SEQUENCE_FIRST_PIXEL_OUT))
+ return -EINVAL;
+
+ /* Check for valid signal edge */
+ if (!(flags & DRM_CRTC_SEQUENCE_FIRST_PIXEL_OUT))
+ return -EINVAL;
+
+ pipe = drm_crtc_index(crtc);
+
+ vblank = &dev->vblank[pipe];
+
+ e = kzalloc(sizeof(*e), GFP_KERNEL);
+ if (e == NULL)
+ return -ENOMEM;
+
+ ret = drm_crtc_vblank_get(crtc);
+ if (ret) {
+ DRM_DEBUG("crtc %d failed to acquire vblank counter, %d\n", pipe, ret);
+ goto err_free;
+ }
+
+ seq = drm_vblank_count_and_time(dev, pipe, &now);
+ req_seq = queue_seq->sequence;
+
+ if (flags & DRM_CRTC_SEQUENCE_RELATIVE)
+ req_seq += seq;
+
+ if ((flags & DRM_CRTC_SEQUENCE_NEXT_ON_MISS) && vblank_passed(seq, req_seq))
+ req_seq = seq + 1;
+
+ e->pipe = pipe;
+ e->event.base.type = DRM_EVENT_CRTC_SEQUENCE;
+ e->event.base.length = sizeof(e->event.seq);
+ e->event.seq.user_data = queue_seq->user_data;
+
+ spin_lock_irqsave(&dev->event_lock, spin_flags);
+
+ /*
+ * drm_crtc_vblank_off() might have been called after we called
+ * drm_crtc_vblank_get(). drm_crtc_vblank_off() holds event_lock around the
+ * vblank disable, so no need for further locking. The reference from
+ * drm_crtc_vblank_get() protects against vblank disable from another source.
+ */
+ if (!READ_ONCE(vblank->enabled)) {
+ ret = -EINVAL;
+ goto err_unlock;
+ }
+
+ ret = drm_event_reserve_init_locked(dev, file_priv, &e->base,
+ &e->event.base);
+
+ if (ret)
+ goto err_unlock;
+
+ e->sequence = req_seq;
+
+ if (vblank_passed(seq, req_seq)) {
+ drm_crtc_vblank_put(crtc);
+ send_vblank_event(dev, e, seq, now);
+ queue_seq->sequence = seq;
+ } else {
+ /* drm_handle_vblank_events will call drm_vblank_put */
+ list_add_tail(&e->base.link, &dev->vblank_event_list);
+ queue_seq->sequence = req_seq;
+ }
+
+ spin_unlock_irqrestore(&dev->event_lock, spin_flags);
+ return 0;
+
+err_unlock:
+ spin_unlock_irqrestore(&dev->event_lock, spin_flags);
+ drm_crtc_vblank_put(crtc);
+err_free:
+ kfree(e);
+ return ret;
+}
diff --git a/include/drm/drm_vblank.h b/include/drm/drm_vblank.h
index 3013c55aec1d..2029313bce89 100644
--- a/include/drm/drm_vblank.h
+++ b/include/drm/drm_vblank.h
@@ -57,6 +57,7 @@ struct drm_pending_vblank_event {
union {
struct drm_event base;
struct drm_event_vblank vbl;
+ struct drm_event_crtc_sequence seq;
} event;
};
diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h
index 101593ab10ac..25478560512a 100644
--- a/include/uapi/drm/drm.h
+++ b/include/uapi/drm/drm.h
@@ -718,6 +718,27 @@ struct drm_syncobj_handle {
__u32 pad;
};
+/* Query current scanout sequence number */
+struct drm_crtc_get_sequence {
+ __u32 crtc_id; /* requested crtc_id */
+ __u32 active; /* return: crtc output is active */
+ __u64 sequence; /* return: most recent vblank sequence */
+ __s64 sequence_ns; /* return: most recent vblank time */
+};
+
+/* Queue event to be delivered at specified sequence */
+
+#define DRM_CRTC_SEQUENCE_RELATIVE 0x00000001 /* sequence is relative to current */
+#define DRM_CRTC_SEQUENCE_NEXT_ON_MISS 0x00000002 /* Use next sequence if we've missed */
+#define DRM_CRTC_SEQUENCE_FIRST_PIXEL_OUT 0x00000004 /* Signal when first pixel is displayed */
+
+struct drm_crtc_queue_sequence {
+ __u32 crtc_id;
+ __u32 flags;
+ __u64 sequence; /* on input, target sequence. on output, actual sequence */
+ __u64 user_data; /* user data passed to event */
+};
+
#if defined(__cplusplus)
}
#endif
@@ -800,6 +821,9 @@ extern "C" {
#define DRM_IOCTL_WAIT_VBLANK DRM_IOWR(0x3a, union drm_wait_vblank)
+#define DRM_IOCTL_CRTC_GET_SEQUENCE DRM_IOWR(0x3b, struct drm_crtc_get_sequence)
+#define DRM_IOCTL_CRTC_QUEUE_SEQUENCE DRM_IOWR(0x3c, struct drm_crtc_queue_sequence)
+
#define DRM_IOCTL_UPDATE_DRAW DRM_IOW(0x3f, struct drm_update_draw)
#define DRM_IOCTL_MODE_GETRESOURCES DRM_IOWR(0xA0, struct drm_mode_card_res)
@@ -871,6 +895,7 @@ struct drm_event {
#define DRM_EVENT_VBLANK 0x01
#define DRM_EVENT_FLIP_COMPLETE 0x02
+#define DRM_EVENT_CRTC_SEQUENCE 0x03
struct drm_event_vblank {
struct drm_event base;
@@ -881,6 +906,13 @@ struct drm_event_vblank {
__u32 crtc_id; /* 0 on older kernels that do not support this */
};
+struct drm_event_crtc_sequence {
+ struct drm_event base;
+ __u64 user_data;
+ __s64 time_ns;
+ __u64 sequence;
+};
+
/* typedef area */
#ifndef __KERNEL__
typedef struct drm_clip_rect drm_clip_rect_t;
--
2.13.3