drm/msm: remove fence_cbs

This was only used for atomic commit these days.  So instead just give
atomic it's own work-queue where we can do a block on each bo in turn.
Simplifies things a whole bunch and makes the 'struct fence' conversion
easier.

Signed-off-by: Rob Clark <robdclark@gmail.com>

6 files changed, 47 insertions, 107 deletions

diff --git a/drivers/gpu/drm/msm/msm_atomic.c b/drivers/gpu/drm/msm/msm_atomic.c
index a2a3d9f25b7b..6ac7192d0ad6 100644
--- a/drivers/gpu/drm/msm/msm_atomic.c
+++ b/drivers/gpu/drm/msm/msm_atomic.c
@@ -18,18 +18,16 @@
 #include "msm_drv.h"
 #include "msm_kms.h"
 #include "msm_gem.h"
-#include "msm_gpu.h"   /* temporary */
 #include "msm_fence.h"
 
 struct msm_commit {
         struct drm_device *dev;
         struct drm_atomic_state *state;
-        uint32_t fence;
-        struct msm_fence_cb fence_cb;
+        struct work_struct work;
         uint32_t crtc_mask;
 };
 
-static void fence_cb(struct msm_fence_cb *cb);
+static void commit_worker(struct work_struct *work);
 
 /* block until specified crtcs are no longer pending update, and
  * atomically mark them as pending update
@@ -71,11 +69,7 @@ static struct msm_commit *commit_init(struct drm_atomic_state *state)
         c->dev = state->dev;
         c->state = state;
 
-        /* TODO we might need a way to indicate to run the cb on a
-         * different wq so wait_for_vblanks() doesn't block retiring
-         * bo's..
-         */
-        INIT_FENCE_CB(&c->fence_cb, fence_cb);
+        INIT_WORK(&c->work, commit_worker);
 
         return c;
 }
@@ -113,16 +107,39 @@ static void msm_atomic_wait_for_commit_done(struct drm_device *dev,
         }
 }
 
+static void wait_fences(struct msm_commit *c, bool async)
+{
+        int nplanes = c->dev->mode_config.num_total_plane;
+        ktime_t timeout = ktime_add_ms(ktime_get(), 1000);
+        int i;
+
+        for (i = 0; i < nplanes; i++) {
+                struct drm_plane *plane = c->state->planes[i];
+                struct drm_plane_state *new_state = c->state->plane_states[i];
+
+                if (!plane)
+                        continue;
+
+                if ((plane->state->fb != new_state->fb) && new_state->fb) {
+                        struct drm_gem_object *obj =
+                                msm_framebuffer_bo(new_state->fb, 0);
+                        msm_gem_cpu_sync(obj, MSM_PREP_READ, &timeout);
+                }
+        }
+}
+
 /* The (potentially) asynchronous part of the commit.  At this point
  * nothing can fail short of armageddon.
  */
-static void complete_commit(struct msm_commit *c)
+static void complete_commit(struct msm_commit *c, bool async)
 {
         struct drm_atomic_state *state = c->state;
         struct drm_device *dev = state->dev;
         struct msm_drm_private *priv = dev->dev_private;
         struct msm_kms *kms = priv->kms;
 
+        wait_fences(c, async);
+
         kms->funcs->prepare_commit(kms, state);
 
         drm_atomic_helper_commit_modeset_disables(dev, state);
@@ -155,17 +172,9 @@ static void complete_commit(struct msm_commit *c)
         commit_destroy(c);
 }
 
-static void fence_cb(struct msm_fence_cb *cb)
+static void commit_worker(struct work_struct *work)
 {
-        struct msm_commit *c =
-                        container_of(cb, struct msm_commit, fence_cb);
-        complete_commit(c);
-}
-
-static void add_fb(struct msm_commit *c, struct drm_framebuffer *fb)
-{
-        struct drm_gem_object *obj = msm_framebuffer_bo(fb, 0);
-        c->fence = max(c->fence, msm_gem_fence(to_msm_bo(obj), MSM_PREP_READ));
+        complete_commit(container_of(work, struct msm_commit, work), true);
 }
 
 int msm_atomic_check(struct drm_device *dev,
@@ -204,9 +213,7 @@ int msm_atomic_commit(struct drm_device *dev,
                 struct drm_atomic_state *state, bool nonblock)
 {
         struct msm_drm_private *priv = dev->dev_private;
-        int nplanes = dev->mode_config.num_total_plane;
         int ncrtcs = dev->mode_config.num_crtc;
-        ktime_t timeout;
         struct msm_commit *c;
         int i, ret;
 
@@ -231,20 +238,6 @@ int msm_atomic_commit(struct drm_device *dev,
         }
 
         /*
-         * Figure out what fence to wait for:
-         */
-        for (i = 0; i < nplanes; i++) {
-                struct drm_plane *plane = state->planes[i];
-                struct drm_plane_state *new_state = state->plane_states[i];
-
-                if (!plane)
-                        continue;
-
-                if ((plane->state->fb != new_state->fb) && new_state->fb)
-                        add_fb(c, new_state->fb);
-        }
-
-        /*
          * Wait for pending updates on any of the same crtc's and then
          * mark our set of crtc's as busy:
          */
@@ -278,18 +271,12 @@ int msm_atomic_commit(struct drm_device *dev,
          * current layout.
          */
 
-        if (nonblock && priv->gpu) {
-                msm_queue_fence_cb(priv->gpu->fctx, &c->fence_cb, c->fence);
+        if (nonblock) {
+                queue_work(priv->atomic_wq, &c->work);
                 return 0;
         }
 
-        timeout = ktime_add_ms(ktime_get(), 1000);
-
-        /* uninterruptible wait */
-        if (priv->gpu)
-                msm_wait_fence(priv->gpu->fctx, c->fence, &timeout, false);
-
-        complete_commit(c);
+        complete_commit(c, false);
 
         return 0;
 
diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c
index 2b859f38772a..745793991ba6 100644
--- a/drivers/gpu/drm/msm/msm_drv.c
+++ b/drivers/gpu/drm/msm/msm_drv.c
@@ -213,6 +213,9 @@ static int msm_unload(struct drm_device *dev)
         flush_workqueue(priv->wq);
         destroy_workqueue(priv->wq);
 
+        flush_workqueue(priv->atomic_wq);
+        destroy_workqueue(priv->atomic_wq);
+
         if (kms) {
                 pm_runtime_disable(dev->dev);
                 kms->funcs->destroy(kms);
@@ -339,6 +342,7 @@ static int msm_load(struct drm_device *dev, unsigned long flags)
         dev->dev_private = priv;
 
         priv->wq = alloc_ordered_workqueue("msm", 0);
+        priv->atomic_wq = alloc_ordered_workqueue("msm:atomic", 0);
         init_waitqueue_head(&priv->pending_crtcs_event);
 
         INIT_LIST_HEAD(&priv->inactive_list);
diff --git a/drivers/gpu/drm/msm/msm_drv.h b/drivers/gpu/drm/msm/msm_drv.h
index 6c3f67bc1bb7..7124c7f262ec 100644
--- a/drivers/gpu/drm/msm/msm_drv.h
+++ b/drivers/gpu/drm/msm/msm_drv.h
@@ -109,6 +109,7 @@ struct msm_drm_private {
         struct list_head inactive_list;
 
         struct workqueue_struct *wq;
+        struct workqueue_struct *atomic_wq;
 
         /* crtcs pending async atomic updates: */
         uint32_t pending_crtcs;
@@ -192,8 +193,8 @@ void *msm_gem_vaddr(struct drm_gem_object *obj);
 void msm_gem_move_to_active(struct drm_gem_object *obj,
                 struct msm_gpu *gpu, bool write, uint32_t fence);
 void msm_gem_move_to_inactive(struct drm_gem_object *obj);
-int msm_gem_cpu_prep(struct drm_gem_object *obj, uint32_t op,
-                ktime_t *timeout);
+int msm_gem_cpu_sync(struct drm_gem_object *obj, uint32_t op, ktime_t *timeout);
+int msm_gem_cpu_prep(struct drm_gem_object *obj, uint32_t op, ktime_t *timeout);
 int msm_gem_cpu_fini(struct drm_gem_object *obj);
 void msm_gem_free_object(struct drm_gem_object *obj);
 int msm_gem_new_handle(struct drm_device *dev, struct drm_file *file,
diff --git a/drivers/gpu/drm/msm/msm_fence.c b/drivers/gpu/drm/msm/msm_fence.c
index f0ed6a680653..088610ca80ca 100644
--- a/drivers/gpu/drm/msm/msm_fence.c
+++ b/drivers/gpu/drm/msm/msm_fence.c
@@ -33,7 +33,6 @@ msm_fence_context_alloc(struct drm_device *dev, const char *name)
         fctx->dev = dev;
         fctx->name = name;
         init_waitqueue_head(&fctx->event);
-        INIT_LIST_HEAD(&fctx->fence_cbs);
 
         return fctx;
 }
@@ -86,54 +85,12 @@ int msm_wait_fence(struct msm_fence_context *fctx, uint32_t fence,
         return ret;
 }
 
-int msm_queue_fence_cb(struct msm_fence_context *fctx,
-                struct msm_fence_cb *cb, uint32_t fence)
-{
-        struct msm_drm_private *priv = fctx->dev->dev_private;
-        int ret = 0;
-
-        mutex_lock(&fctx->dev->struct_mutex);
-        if (!list_empty(&cb->work.entry)) {
-                ret = -EINVAL;
-        } else if (fence > fctx->completed_fence) {
-                cb->fence = fence;
-                list_add_tail(&cb->work.entry, &fctx->fence_cbs);
-        } else {
-                queue_work(priv->wq, &cb->work);
-        }
-        mutex_unlock(&fctx->dev->struct_mutex);
-
-        return ret;
-}
-
 /* called from workqueue */
 void msm_update_fence(struct msm_fence_context *fctx, uint32_t fence)
 {
-        struct msm_drm_private *priv = fctx->dev->dev_private;
-
         mutex_lock(&fctx->dev->struct_mutex);
         fctx->completed_fence = max(fence, fctx->completed_fence);
-
-        while (!list_empty(&fctx->fence_cbs)) {
-                struct msm_fence_cb *cb;
-
-                cb = list_first_entry(&fctx->fence_cbs,
-                                struct msm_fence_cb, work.entry);
-
-                if (cb->fence > fctx->completed_fence)
-                        break;
-
-                list_del_init(&cb->work.entry);
-                queue_work(priv->wq, &cb->work);
-        }
-
         mutex_unlock(&fctx->dev->struct_mutex);
 
         wake_up_all(&fctx->event);
 }
-
-void __msm_fence_worker(struct work_struct *work)
-{
-        struct msm_fence_cb *cb = container_of(work, struct msm_fence_cb, work);
-        cb->func(cb);
-}
diff --git a/drivers/gpu/drm/msm/msm_fence.h b/drivers/gpu/drm/msm/msm_fence.h
index 3ed20981fc05..2820781d974a 100644
--- a/drivers/gpu/drm/msm/msm_fence.h
+++ b/drivers/gpu/drm/msm/msm_fence.h
@@ -27,28 +27,12 @@ struct msm_fence_context {
         uint32_t last_fence;          /* last assigned fence */
         uint32_t completed_fence;     /* last completed fence */
         wait_queue_head_t event;
-        /* callbacks deferred until bo is inactive: */
-        struct list_head fence_cbs;
 };
 
 struct msm_fence_context * msm_fence_context_alloc(struct drm_device *dev,
                 const char *name);
 void msm_fence_context_free(struct msm_fence_context *fctx);
 
-/* callback from wq once fence has passed: */
-struct msm_fence_cb {
-        struct work_struct work;
-        uint32_t fence;
-        void (*func)(struct msm_fence_cb *cb);
-};
-
-void __msm_fence_worker(struct work_struct *work);
-
-#define INIT_FENCE_CB(_cb, _func)  do {                     \
-                INIT_WORK(&(_cb)->work, __msm_fence_worker); \
-                (_cb)->func = _func;                         \
-        } while (0)
-
 int msm_wait_fence(struct msm_fence_context *fctx, uint32_t fence,
                 ktime_t *timeout, bool interruptible);
 int msm_queue_fence_cb(struct msm_fence_context *fctx,
diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c
index 80aba76f7a4d..9080ed13998a 100644
--- a/drivers/gpu/drm/msm/msm_gem.c
+++ b/drivers/gpu/drm/msm/msm_gem.c
@@ -439,7 +439,7 @@ void msm_gem_move_to_inactive(struct drm_gem_object *obj)
         list_add_tail(&msm_obj->mm_list, &priv->inactive_list);
 }
 
-int msm_gem_cpu_prep(struct drm_gem_object *obj, uint32_t op, ktime_t *timeout)
+int msm_gem_cpu_sync(struct drm_gem_object *obj, uint32_t op, ktime_t *timeout)
 {
         struct drm_device *dev = obj->dev;
         struct msm_drm_private *priv = dev->dev_private;
@@ -456,6 +456,13 @@ int msm_gem_cpu_prep(struct drm_gem_object *obj, uint32_t op, ktime_t *timeout)
                         ret = msm_wait_fence(priv->gpu->fctx, fence, timeout, true);
         }
 
+        return ret;
+}
+
+int msm_gem_cpu_prep(struct drm_gem_object *obj, uint32_t op, ktime_t *timeout)
+{
+        int ret = msm_gem_cpu_sync(obj, op, timeout);
+
         /* TODO cache maintenance */
 
         return ret;