vmwgfx: Add fence events
[pandora-kernel.git] / drivers / gpu / drm / vmwgfx / vmwgfx_fence.c
index 5f60be7..35d5f61 100644 (file)
@@ -34,13 +34,18 @@ struct vmw_fence_manager {
        int num_fence_objects;
        struct vmw_private *dev_priv;
        spinlock_t lock;
-       u32 next_seqno;
        struct list_head fence_list;
        struct work_struct work;
        u32 user_fence_size;
        u32 fence_size;
+       u32 event_fence_action_size;
        bool fifo_down;
        struct list_head cleanup_list;
+       uint32_t pending_actions[VMW_ACTION_MAX];
+       struct mutex goal_irq_mutex;
+       bool goal_irq_on; /* Protected by @goal_irq_mutex */
+       bool seqno_valid; /* Protected by @lock, and may not be set to true
+                            without the @goal_irq_mutex held. */
 };
 
 struct vmw_user_fence {
@@ -49,8 +54,51 @@ struct vmw_user_fence {
 };
 
 /**
- * vmw_fence_destroy_locked
+ * struct vmw_event_fence_action - fence action that delivers a drm event.
  *
+ * @e: A struct drm_pending_event that controls the event delivery.
+ * @action: A struct vmw_fence_action to hook up to a fence.
+ * @fence: A referenced pointer to the fence to keep it alive while @action
+ * hangs on it.
+ * @dev: Pointer to a struct drm_device so we can access the event stuff.
+ * @kref: Both @e and @action has destructors, so we need to refcount.
+ * @size: Size accounted for this object.
+ * @tv_sec: If non-null, the variable pointed to will be assigned
+ * current time tv_sec val when the fence signals.
+ * @tv_usec: Must be set if @tv_sec is set, and the variable pointed to will
+ * be assigned the current time tv_usec val when the fence signals.
+ */
+struct vmw_event_fence_action {
+       struct drm_pending_event e;
+       struct vmw_fence_action action;
+       struct vmw_fence_obj *fence;
+       struct drm_device *dev;
+       struct kref kref;
+       uint32_t size;
+       uint32_t *tv_sec;
+       uint32_t *tv_usec;
+};
+
+/**
+ * Note on fencing subsystem usage of irqs:
+ * Typically the vmw_fences_update function is called
+ *
+ * a) When a new fence seqno has been submitted by the fifo code.
+ * b) On-demand when we have waiters. Sleeping waiters will switch on the
+ * ANY_FENCE irq and call vmw_fences_update function each time an ANY_FENCE
+ * irq is received. When the last fence waiter is gone, that IRQ is masked
+ * away.
+ *
+ * In situations where there are no waiters and we don't submit any new fences,
+ * fence objects may not be signaled. This is perfectly OK, since there are
+ * no consumers of the signaled data, but that is NOT ok when there are fence
+ * actions attached to a fence. The fencing subsystem then makes use of the
+ * FENCE_GOAL irq and sets the fence goal seqno to that of the next fence
+ * which has an action attached, and each time vmw_fences_update is called,
+ * the subsystem makes sure the fence goal seqno is updated.
+ *
+ * The fence goal seqno irq is on as long as there are unsignaled fence
+ * objects with actions attached to them.
  */
 
 static void vmw_fence_obj_destroy_locked(struct kref *kref)
@@ -85,24 +133,36 @@ static void vmw_fence_work_func(struct work_struct *work)
                container_of(work, struct vmw_fence_manager, work);
        struct list_head list;
        struct vmw_fence_action *action, *next_action;
+       bool seqno_valid;
 
        do {
                INIT_LIST_HEAD(&list);
+               mutex_lock(&fman->goal_irq_mutex);
+
                spin_lock_irq(&fman->lock);
                list_splice_init(&fman->cleanup_list, &list);
+               seqno_valid = fman->seqno_valid;
                spin_unlock_irq(&fman->lock);
 
+               if (!seqno_valid && fman->goal_irq_on) {
+                       fman->goal_irq_on = false;
+                       vmw_goal_waiter_remove(fman->dev_priv);
+               }
+               mutex_unlock(&fman->goal_irq_mutex);
+
                if (list_empty(&list))
                        return;
 
                /*
                 * At this point, only we should be able to manipulate the
                 * list heads of the actions we have on the private list.
+                * hence fman::lock not held.
                 */
 
                list_for_each_entry_safe(action, next_action, &list, head) {
                        list_del_init(&action->head);
-                       action->cleanup(action);
+                       if (action->cleanup)
+                               action->cleanup(action);
                }
        } while (1);
 }
@@ -122,6 +182,9 @@ struct vmw_fence_manager *vmw_fence_manager_init(struct vmw_private *dev_priv)
        fman->fifo_down = true;
        fman->user_fence_size = ttm_round_pot(sizeof(struct vmw_user_fence));
        fman->fence_size = ttm_round_pot(sizeof(struct vmw_fence_obj));
+       fman->event_fence_action_size =
+               ttm_round_pot(sizeof(struct vmw_event_fence_action));
+       mutex_init(&fman->goal_irq_mutex);
 
        return fman;
 }
@@ -214,6 +277,7 @@ void vmw_fences_perform_actions(struct vmw_fence_manager *fman,
 
        list_for_each_entry_safe(action, next_action, list, head) {
                list_del_init(&action->head);
+               fman->pending_actions[action->type]--;
                if (action->seq_passed != NULL)
                        action->seq_passed(action);
 
@@ -222,17 +286,101 @@ void vmw_fences_perform_actions(struct vmw_fence_manager *fman,
                 * it will be performed by a worker task.
                 */
 
-               if (action->cleanup != NULL)
-                       list_add_tail(&action->head, &fman->cleanup_list);
+               list_add_tail(&action->head, &fman->cleanup_list);
+       }
+}
+
+/**
+ * vmw_fence_goal_new_locked - Figure out a new device fence goal
+ * seqno if needed.
+ *
+ * @fman: Pointer to a fence manager.
+ * @passed_seqno: The seqno the device currently signals as passed.
+ *
+ * This function should be called with the fence manager lock held.
+ * It is typically called when we have a new passed_seqno, and
+ * we might need to update the fence goal. It checks to see whether
+ * the current fence goal has already passed, and, in that case,
+ * scans through all unsignaled fences to get the next fence object with an
+ * action attached, and sets the seqno of that fence as a new fence goal.
+ *
+ * returns true if the device goal seqno was updated. False otherwise.
+ */
+static bool vmw_fence_goal_new_locked(struct vmw_fence_manager *fman,
+                                     u32 passed_seqno)
+{
+       u32 goal_seqno;
+       __le32 __iomem *fifo_mem;
+       struct vmw_fence_obj *fence;
+
+       if (likely(!fman->seqno_valid))
+               return false;
+
+       fifo_mem = fman->dev_priv->mmio_virt;
+       goal_seqno = ioread32(fifo_mem + SVGA_FIFO_FENCE_GOAL);
+       if (likely(passed_seqno - goal_seqno >= VMW_FENCE_WRAP))
+               return false;
+
+       fman->seqno_valid = false;
+       list_for_each_entry(fence, &fman->fence_list, head) {
+               if (!list_empty(&fence->seq_passed_actions)) {
+                       fman->seqno_valid = true;
+                       iowrite32(fence->seqno,
+                                 fifo_mem + SVGA_FIFO_FENCE_GOAL);
+                       break;
+               }
        }
+
+       return true;
+}
+
+
+/**
+ * vmw_fence_goal_check_locked - Replace the device fence goal seqno if
+ * needed.
+ *
+ * @fence: Pointer to a struct vmw_fence_obj the seqno of which should be
+ * considered as a device fence goal.
+ *
+ * This function should be called with the fence manager lock held.
+ * It is typically called when an action has been attached to a fence to
+ * check whether the seqno of that fence should be used for a fence
+ * goal interrupt. This is typically needed if the current fence goal is
+ * invalid, or has a higher seqno than that of the current fence object.
+ *
+ * returns true if the device goal seqno was updated. False otherwise.
+ */
+static bool vmw_fence_goal_check_locked(struct vmw_fence_obj *fence)
+{
+       u32 goal_seqno;
+       __le32 __iomem *fifo_mem;
+
+       if (fence->signaled & DRM_VMW_FENCE_FLAG_EXEC)
+               return false;
+
+       fifo_mem = fence->fman->dev_priv->mmio_virt;
+       goal_seqno = ioread32(fifo_mem + SVGA_FIFO_FENCE_GOAL);
+       if (likely(fence->fman->seqno_valid &&
+                  goal_seqno - fence->seqno < VMW_FENCE_WRAP))
+               return false;
+
+       iowrite32(fence->seqno, fifo_mem + SVGA_FIFO_FENCE_GOAL);
+       fence->fman->seqno_valid = true;
+
+       return true;
 }
 
-void vmw_fences_update(struct vmw_fence_manager *fman, u32 seqno)
+void vmw_fences_update(struct vmw_fence_manager *fman)
 {
        unsigned long flags;
        struct vmw_fence_obj *fence, *next_fence;
        struct list_head action_list;
+       bool needs_rerun;
+       uint32_t seqno, new_seqno;
+       __le32 __iomem *fifo_mem = fman->dev_priv->mmio_virt;
 
+       seqno = ioread32(fifo_mem + SVGA_FIFO_FENCE);
+rerun:
        spin_lock_irqsave(&fman->lock, flags);
        list_for_each_entry_safe(fence, next_fence, &fman->fence_list, head) {
                if (seqno - fence->seqno < VMW_FENCE_WRAP) {
@@ -243,14 +391,30 @@ void vmw_fences_update(struct vmw_fence_manager *fman, u32 seqno)
                                         &action_list);
                        vmw_fences_perform_actions(fman, &action_list);
                        wake_up_all(&fence->queue);
-               }
-
+               } else
+                       break;
        }
+
+       needs_rerun = vmw_fence_goal_new_locked(fman, seqno);
+
        if (!list_empty(&fman->cleanup_list))
                (void) schedule_work(&fman->work);
        spin_unlock_irqrestore(&fman->lock, flags);
-}
 
+       /*
+        * Rerun if the fence goal seqno was updated, and the
+        * hardware might have raced with that update, so that
+        * we missed a fence_goal irq.
+        */
+
+       if (unlikely(needs_rerun)) {
+               new_seqno = ioread32(fifo_mem + SVGA_FIFO_FENCE);
+               if (new_seqno != seqno) {
+                       seqno = new_seqno;
+                       goto rerun;
+               }
+       }
+}
 
 bool vmw_fence_obj_signaled(struct vmw_fence_obj *fence,
                            uint32_t flags)
@@ -267,14 +431,8 @@ bool vmw_fence_obj_signaled(struct vmw_fence_obj *fence,
        if ((signaled & flags) == flags)
                return 1;
 
-       if ((signaled & DRM_VMW_FENCE_FLAG_EXEC) == 0) {
-               struct vmw_private *dev_priv = fman->dev_priv;
-               __le32 __iomem *fifo_mem = dev_priv->mmio_virt;
-               u32 seqno;
-
-               seqno = ioread32(fifo_mem + SVGA_FIFO_FENCE);
-               vmw_fences_update(fman, seqno);
-       }
+       if ((signaled & DRM_VMW_FENCE_FLAG_EXEC) == 0)
+               vmw_fences_update(fman);
 
        spin_lock_irqsave(&fman->lock, irq_flags);
        signaled = fence->signaled;
@@ -624,3 +782,344 @@ int vmw_fence_obj_unref_ioctl(struct drm_device *dev, void *data,
                                         arg->handle,
                                         TTM_REF_USAGE);
 }
+
+/**
+ * vmw_event_fence_action_destroy
+ *
+ * @kref: The struct kref embedded in a struct vmw_event_fence_action.
+ *
+ * The vmw_event_fence_action destructor that may be called either after
+ * the fence action cleanup, or when the event is delivered.
+ * It frees both the vmw_event_fence_action struct and the actual
+ * event structure copied to user-space.
+ */
+static void vmw_event_fence_action_destroy(struct kref *kref)
+{
+       struct vmw_event_fence_action *eaction =
+               container_of(kref, struct vmw_event_fence_action, kref);
+       struct ttm_mem_global *mem_glob =
+               vmw_mem_glob(vmw_priv(eaction->dev));
+       uint32_t size = eaction->size;
+
+       kfree(eaction->e.event);
+       kfree(eaction);
+       ttm_mem_global_free(mem_glob, size);
+}
+
+
+/**
+ * vmw_event_fence_action_delivered
+ *
+ * @e: The struct drm_pending_event embedded in a struct
+ * vmw_event_fence_action.
+ *
+ * The struct drm_pending_event destructor that is called by drm
+ * once the event is delivered. Since we don't know whether this function
+ * will be called before or after the fence action destructor, we
+ * free a refcount and destroy if it becomes zero.
+ */
+static void vmw_event_fence_action_delivered(struct drm_pending_event *e)
+{
+       struct vmw_event_fence_action *eaction =
+               container_of(e, struct vmw_event_fence_action, e);
+
+       kref_put(&eaction->kref, vmw_event_fence_action_destroy);
+}
+
+
+/**
+ * vmw_event_fence_action_seq_passed
+ *
+ * @action: The struct vmw_fence_action embedded in a struct
+ * vmw_event_fence_action.
+ *
+ * This function is called when the seqno of the fence where @action is
+ * attached has passed. It queues the event on the submitter's event list.
+ * This function is always called from atomic context, and may be called
+ * from irq context. It ups a refcount reflecting that we now have two
+ * destructors.
+ */
+static void vmw_event_fence_action_seq_passed(struct vmw_fence_action *action)
+{
+       struct vmw_event_fence_action *eaction =
+               container_of(action, struct vmw_event_fence_action, action);
+       struct drm_device *dev = eaction->dev;
+       struct drm_file *file_priv = eaction->e.file_priv;
+       unsigned long irq_flags;
+
+       kref_get(&eaction->kref);
+       spin_lock_irqsave(&dev->event_lock, irq_flags);
+
+       if (likely(eaction->tv_sec != NULL)) {
+               struct timeval tv;
+
+               do_gettimeofday(&tv);
+               *eaction->tv_sec = tv.tv_sec;
+               *eaction->tv_usec = tv.tv_usec;
+       }
+
+       list_add_tail(&eaction->e.link, &file_priv->event_list);
+       wake_up_all(&file_priv->event_wait);
+       spin_unlock_irqrestore(&dev->event_lock, irq_flags);
+}
+
+/**
+ * vmw_event_fence_action_cleanup
+ *
+ * @action: The struct vmw_fence_action embedded in a struct
+ * vmw_event_fence_action.
+ *
+ * This function is the struct vmw_fence_action destructor. It's typically
+ * called from a workqueue.
+ */
+static void vmw_event_fence_action_cleanup(struct vmw_fence_action *action)
+{
+       struct vmw_event_fence_action *eaction =
+               container_of(action, struct vmw_event_fence_action, action);
+
+       vmw_fence_obj_unreference(&eaction->fence);
+       kref_put(&eaction->kref, vmw_event_fence_action_destroy);
+}
+
+
+/**
+ * vmw_fence_obj_add_action - Add an action to a fence object.
+ *
+ * @fence - The fence object.
+ * @action - The action to add.
+ *
+ * Note that the action callbacks may be executed before this function
+ * returns.
+ */
+void vmw_fence_obj_add_action(struct vmw_fence_obj *fence,
+                             struct vmw_fence_action *action)
+{
+       struct vmw_fence_manager *fman = fence->fman;
+       unsigned long irq_flags;
+       bool run_update = false;
+
+       mutex_lock(&fman->goal_irq_mutex);
+       spin_lock_irqsave(&fman->lock, irq_flags);
+
+       fman->pending_actions[action->type]++;
+       if (fence->signaled & DRM_VMW_FENCE_FLAG_EXEC) {
+               struct list_head action_list;
+
+               INIT_LIST_HEAD(&action_list);
+               list_add_tail(&action->head, &action_list);
+               vmw_fences_perform_actions(fman, &action_list);
+       } else {
+               list_add_tail(&action->head, &fence->seq_passed_actions);
+
+               /*
+                * This function may set fman::seqno_valid, so it must
+                * be run with the goal_irq_mutex held.
+                */
+               run_update = vmw_fence_goal_check_locked(fence);
+       }
+
+       spin_unlock_irqrestore(&fman->lock, irq_flags);
+
+       if (run_update) {
+               if (!fman->goal_irq_on) {
+                       fman->goal_irq_on = true;
+                       vmw_goal_waiter_add(fman->dev_priv);
+               }
+               vmw_fences_update(fman);
+       }
+       mutex_unlock(&fman->goal_irq_mutex);
+
+}
+
+/**
+ * vmw_event_fence_action_create - Post an event for sending when a fence
+ * object seqno has passed.
+ *
+ * @file_priv: The file connection on which the event should be posted.
+ * @fence: The fence object on which to post the event.
+ * @event: Event to be posted. This event should've been alloced
+ * using k[mz]alloc, and should've been completely initialized.
+ * @interruptible: Interruptible waits if possible.
+ *
+ * As a side effect, the object pointed to by @event may have been
+ * freed when this function returns. If this function returns with
+ * an error code, the caller needs to free that object.
+ */
+
+int vmw_event_fence_action_create(struct drm_file *file_priv,
+                                 struct vmw_fence_obj *fence,
+                                 struct drm_event *event,
+                                 uint32_t *tv_sec,
+                                 uint32_t *tv_usec,
+                                 bool interruptible)
+{
+       struct vmw_event_fence_action *eaction =
+               kzalloc(sizeof(*eaction), GFP_KERNEL);
+       struct ttm_mem_global *mem_glob =
+               vmw_mem_glob(fence->fman->dev_priv);
+       struct vmw_fence_manager *fman = fence->fman;
+       uint32_t size = fman->event_fence_action_size +
+               ttm_round_pot(event->length);
+       int ret;
+
+       /*
+        * Account for internal structure size as well as the
+        * event size itself.
+        */
+
+       ret = ttm_mem_global_alloc(mem_glob, size, false, interruptible);
+       if (unlikely(ret != 0))
+               return ret;
+
+       eaction = kzalloc(sizeof(*eaction), GFP_KERNEL);
+       if (unlikely(eaction == NULL)) {
+               ttm_mem_global_free(mem_glob, size);
+               return -ENOMEM;
+       }
+
+       eaction->e.event = event;
+       eaction->e.file_priv = file_priv;
+       eaction->e.destroy = vmw_event_fence_action_delivered;
+
+       eaction->action.seq_passed = vmw_event_fence_action_seq_passed;
+       eaction->action.cleanup = vmw_event_fence_action_cleanup;
+       eaction->action.type = VMW_ACTION_EVENT;
+
+       eaction->fence = vmw_fence_obj_reference(fence);
+       eaction->dev = fman->dev_priv->dev;
+       eaction->size = size;
+       eaction->tv_sec = tv_sec;
+       eaction->tv_usec = tv_usec;
+
+       kref_init(&eaction->kref);
+       vmw_fence_obj_add_action(fence, &eaction->action);
+
+       return 0;
+}
+
+int vmw_fence_event_ioctl(struct drm_device *dev, void *data,
+                         struct drm_file *file_priv)
+{
+       struct vmw_private *dev_priv = vmw_priv(dev);
+       struct drm_vmw_fence_event_arg *arg =
+               (struct drm_vmw_fence_event_arg *) data;
+       struct vmw_fence_obj *fence = NULL;
+       struct vmw_fpriv *vmw_fp = vmw_fpriv(file_priv);
+       struct drm_vmw_fence_rep __user *user_fence_rep =
+               (struct drm_vmw_fence_rep __user *)(unsigned long)
+               arg->fence_rep;
+       uint32_t handle;
+       unsigned long irq_flags;
+       struct drm_vmw_event_fence *event;
+       int ret;
+
+       /*
+        * Look up an existing fence object,
+        * and if user-space wants a new reference,
+        * add one.
+        */
+       if (arg->handle) {
+               struct ttm_base_object *base =
+                       ttm_base_object_lookup(vmw_fp->tfile, arg->handle);
+
+               if (unlikely(base == NULL)) {
+                       DRM_ERROR("Fence event invalid fence object handle "
+                                 "0x%08lx.\n",
+                                 (unsigned long)arg->handle);
+                       return -EINVAL;
+               }
+               fence = &(container_of(base, struct vmw_user_fence,
+                                      base)->fence);
+               (void) vmw_fence_obj_reference(fence);
+
+               if (user_fence_rep != NULL) {
+                       bool existed;
+
+                       ret = ttm_ref_object_add(vmw_fp->tfile, base,
+                                                TTM_REF_USAGE, &existed);
+                       if (unlikely(ret != 0)) {
+                               DRM_ERROR("Failed to reference a fence "
+                                         "object.\n");
+                               goto out_no_ref_obj;
+                       }
+                       handle = base->hash.key;
+               }
+               ttm_base_object_unref(&base);
+       }
+
+       /*
+        * Create a new fence object.
+        */
+       if (!fence) {
+               ret = vmw_execbuf_fence_commands(file_priv, dev_priv,
+                                                &fence,
+                                                (user_fence_rep) ?
+                                                &handle : NULL);
+               if (unlikely(ret != 0)) {
+                       DRM_ERROR("Fence event failed to create fence.\n");
+                       return ret;
+               }
+       }
+
+       BUG_ON(fence == NULL);
+
+       spin_lock_irqsave(&dev->event_lock, irq_flags);
+
+       ret = (file_priv->event_space < sizeof(*event)) ? -EBUSY : 0;
+       if (likely(ret == 0))
+               file_priv->event_space -= sizeof(*event);
+
+       spin_unlock_irqrestore(&dev->event_lock, irq_flags);
+
+       if (unlikely(ret != 0)) {
+               DRM_ERROR("Failed to allocate event space for this file.\n");
+               goto out_no_event_space;
+       }
+
+       event = kzalloc(sizeof(*event), GFP_KERNEL);
+       if (unlikely(event == NULL)) {
+               DRM_ERROR("Failed to allocate an event.\n");
+               goto out_no_event;
+       }
+
+       event->base.type = DRM_VMW_EVENT_FENCE_SIGNALED;
+       event->base.length = sizeof(*event);
+       event->user_data = arg->user_data;
+
+       if (arg->flags & DRM_VMW_FE_FLAG_REQ_TIME)
+               ret = vmw_event_fence_action_create(file_priv, fence,
+                                                   &event->base,
+                                                   &event->tv_sec,
+                                                   &event->tv_usec,
+                                                   true);
+       else
+               ret = vmw_event_fence_action_create(file_priv, fence,
+                                                   &event->base,
+                                                   NULL,
+                                                   NULL,
+                                                   true);
+
+       if (unlikely(ret != 0)) {
+               if (ret != -ERESTARTSYS)
+                       DRM_ERROR("Failed to attach event to fence.\n");
+               goto out_no_attach;
+       }
+
+       vmw_execbuf_copy_fence_user(dev_priv, vmw_fp, 0, user_fence_rep, fence,
+                                   handle);
+       vmw_fence_obj_unreference(&fence);
+       return 0;
+out_no_attach:
+       kfree(event);
+out_no_event:
+       spin_lock_irqsave(&dev->event_lock, irq_flags);
+       file_priv->event_space += sizeof(*event);
+       spin_unlock_irqrestore(&dev->event_lock, irq_flags);
+out_no_event_space:
+       if (user_fence_rep != NULL)
+               ttm_ref_object_base_unref(vmw_fpriv(file_priv)->tfile,
+                                         handle, TTM_REF_USAGE);
+out_no_ref_obj:
+       vmw_fence_obj_unreference(&fence);
+       return ret;
+}