gpu: nvgpu: Add gk20a_fence type

When moving compression state tracking and compbit management ops to
kernel, we need to attach a fence to dma-buf metadata, along with the
compbit state.

To make in-kernel fence management easier, introduce a new gk20a_fence
abstraction. A gk20a_fence may be backed by a semaphore or a syncpoint
(id, value) pair. If the kernel is configured with CONFIG_SYNC, it will
also contain a sync_fence. The gk20a_fence can easily be converted back
to a syncpoint (id, value) parir or sync FD when we need to return it to
user space.

Change gk20a_submit_channel_gpfifo to return a gk20a_fence instead of
nvhost_fence. This is to facilitate work submission initiated from
kernel.

Bug 1509620

Change-Id: I6154764a279dba83f5e91ba9e0cb5e227ca08e1b
Signed-off-by: Lauri Peltonen <lpeltonen@nvidia.com>
Reviewed-on: http://git-master/r/439846
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>
Tested-by: Terje Bergstrom <tbergstrom@nvidia.com>

1 files changed, 28 insertions, 46 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/channel_sync_gk20a.h b/drivers/gpu/nvgpu/gk20a/channel_sync_gk20a.h
index baa4a151..a3cd8208 100644
--- a/drivers/gpu/nvgpu/gk20a/channel_sync_gk20a.h
+++ b/drivers/gpu/nvgpu/gk20a/channel_sync_gk20a.h
@@ -24,34 +24,28 @@ struct gk20a_channel_sync;
 struct priv_cmd_entry;
 struct channel_gk20a;
 struct gk20a_semaphore;
-
-struct gk20a_channel_fence {
-        bool valid;
-        bool wfi; /* was issued with preceding wfi */
-        u32 thresh; /* syncpoint fences only */
-        struct gk20a_semaphore *semaphore; /* semaphore fences only */
-};
+struct gk20a_fence;
 
 struct gk20a_channel_sync {
-        /* CPU wait for a fence returned by incr_syncpt() or incr_fd(). */
-        int (*wait_cpu)(struct gk20a_channel_sync *s,
-                        struct gk20a_channel_fence *fence,
-                        int timeout);
-
-        /* Test whether a fence returned by incr_syncpt() or incr_fd() is
-         * expired. */
-        bool (*is_expired)(struct gk20a_channel_sync *s,
-                           struct gk20a_channel_fence *fence);
-
-        /* Generate a gpu wait cmdbuf from syncpoint. */
+        /* Generate a gpu wait cmdbuf from syncpoint.
+         * Returns
+         *  - a gpu cmdbuf that performs the wait when executed,
+         *  - possibly a helper fence that the caller must hold until the
+         *    cmdbuf is executed.
+         */
         int (*wait_syncpt)(struct gk20a_channel_sync *s, u32 id, u32 thresh,
                            struct priv_cmd_entry **entry,
-                           struct gk20a_channel_fence *fence);
+                           struct gk20a_fence **fence);
 
-        /* Generate a gpu wait cmdbuf from sync fd. */
+        /* Generate a gpu wait cmdbuf from sync fd.
+         * Returns
+         *  - a gpu cmdbuf that performs the wait when executed,
+         *  - possibly a helper fence that the caller must hold until the
+         *    cmdbuf is executed.
+         */
         int (*wait_fd)(struct gk20a_channel_sync *s, int fd,
                        struct priv_cmd_entry **entry,
-                       struct gk20a_channel_fence *fence);
+                       struct gk20a_fence **fence);
 
         /* Increment syncpoint/semaphore.
          * Returns
@@ -60,7 +54,7 @@ struct gk20a_channel_sync {
          */
         int (*incr)(struct gk20a_channel_sync *s,
                     struct priv_cmd_entry **entry,
-                    struct gk20a_channel_fence *fence);
+                    struct gk20a_fence **fence);
 
         /* Increment syncpoint/semaphore, preceded by a wfi.
          * Returns
@@ -69,38 +63,29 @@ struct gk20a_channel_sync {
          */
         int (*incr_wfi)(struct gk20a_channel_sync *s,
                         struct priv_cmd_entry **entry,
-                        struct gk20a_channel_fence *fence);
-
-        /* Increment syncpoint, so that the returned fence represents
-         * work completion (may need wfi) and can be returned to user space.
-         * Returns
-         *  - a gpu cmdbuf that performs the increment when executed,
-         *  - a fence that can be passed to wait_cpu() and is_expired(),
-         *  - a syncpoint id/value pair that can be returned to user space.
-         */
-        int (*incr_user_syncpt)(struct gk20a_channel_sync *s,
-                                struct priv_cmd_entry **entry,
-                                struct gk20a_channel_fence *fence,
-                                bool wfi,
-                                u32 *id, u32 *thresh);
+                        struct gk20a_fence **fence);
 
         /* Increment syncpoint/semaphore, so that the returned fence represents
          * work completion (may need wfi) and can be returned to user space.
          * Returns
          *  - a gpu cmdbuf that performs the increment when executed,
          *  - a fence that can be passed to wait_cpu() and is_expired(),
-         *  - a sync fd that can be returned to user space.
+         *  - a gk20a_fence that signals when the incr has happened.
          */
-        int (*incr_user_fd)(struct gk20a_channel_sync *s,
-                            int wait_fence_fd,
-                            struct priv_cmd_entry **entry,
-                            struct gk20a_channel_fence *fence,
-                            bool wfi,
-                            int *fd);
+        int (*incr_user)(struct gk20a_channel_sync *s,
+                         int wait_fence_fd,
+                         struct priv_cmd_entry **entry,
+                         struct gk20a_fence **fence,
+                         bool wfi);
 
         /* Reset the channel syncpoint/semaphore. */
         void (*set_min_eq_max)(struct gk20a_channel_sync *s);
 
+        /* Signals the sync timeline (if owned by the gk20a_channel_sync layer).
+         * This should be called when we notice that a gk20a_fence is
+         * expired. */
+        void (*signal_timeline)(struct gk20a_channel_sync *s);
+
         /* flag to set sync destroy aggressiveness */
         bool aggressive_destroy;
 
@@ -110,7 +95,4 @@ struct gk20a_channel_sync {
 
 struct gk20a_channel_sync *gk20a_channel_sync_create(struct channel_gk20a *c);
 
-void gk20a_channel_fence_close(struct gk20a_channel_fence *f);
-void gk20a_channel_fence_dup(struct gk20a_channel_fence *from,
-                             struct gk20a_channel_fence *to);
 #endif