drm/vc4: Syncobj import support

Allow userland to specify a syncobj that is waited on before a render job
starts processing.

v2: Use 0 as invalid syncobj to drop flag (Eric)
    Drop extra newline (Eric)

Signed-off-by: Stefan Schake <stschake@gmail.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/1524607427-12876-2-git-send-email-stschake@gmail.com

diff --git a/drivers/gpu/drm/vc4/vc4_drv.h b/drivers/gpu/drm/vc4/vc4_drv.h
index 22589d3..554a4e8 100644 (file)
--- a/drivers/gpu/drm/vc4/vc4_drv.h
+++ b/drivers/gpu/drm/vc4/vc4_drv.h
@@ -11,6 +11,7 @@
 #include <drm/drm_encoder.h>
 #include <drm/drm_gem_cma_helper.h>
 #include <drm/drm_atomic.h>
+#include <drm/drm_syncobj.h>
 
 #include "uapi/drm/vc4_drm.h"
 

diff --git a/drivers/gpu/drm/vc4/vc4_gem.c b/drivers/gpu/drm/vc4/vc4_gem.c
index 2107b0d..e305ccd 100644 (file)
--- a/drivers/gpu/drm/vc4/vc4_gem.c
+++ b/drivers/gpu/drm/vc4/vc4_gem.c
@@ -27,6 +27,7 @@
 #include <linux/device.h>
 #include <linux/io.h>
 #include <linux/sched/signal.h>
+#include <linux/dma-fence-array.h>
 
 #include "uapi/drm/vc4_drm.h"
 #include "vc4_drv.h"
@@ -1115,6 +1116,7 @@ vc4_submit_cl_ioctl(struct drm_device *dev, void *data,
        struct drm_vc4_submit_cl *args = data;
        struct vc4_exec_info *exec;
        struct ww_acquire_ctx acquire_ctx;
+       struct dma_fence *in_fence;
        int ret = 0;
 
        if ((args->flags & ~(VC4_SUBMIT_CL_USE_CLEAR_COLOR |
@@ -1125,11 +1127,6 @@ vc4_submit_cl_ioctl(struct drm_device *dev, void *data,
                return -EINVAL;
        }
 
-       if (args->pad2 != 0) {
-               DRM_DEBUG("->pad2 must be set to zero\n");
-               return -EINVAL;
-       }
-
        exec = kcalloc(1, sizeof(*exec), GFP_KERNEL);
        if (!exec) {
                DRM_ERROR("malloc failure on exec struct\n");
@@ -1164,6 +1161,29 @@ vc4_submit_cl_ioctl(struct drm_device *dev, void *data,
                }
        }
 
+       if (args->in_sync) {
+               ret = drm_syncobj_find_fence(file_priv, args->in_sync,
+                                            &in_fence);
+               if (ret)
+                       goto fail;
+
+               /* When the fence (or fence array) is exclusively from our
+                * context we can skip the wait since jobs are executed in
+                * order of their submission through this ioctl and this can
+                * only have fences from a prior job.
+                */
+               if (!dma_fence_match_context(in_fence,
+                                            vc4->dma_fence_context)) {
+                       ret = dma_fence_wait(in_fence, true);
+                       if (ret) {
+                               dma_fence_put(in_fence);
+                               goto fail;
+                       }
+               }
+
+               dma_fence_put(in_fence);
+       }
+
        if (exec->args->bin_cl_size != 0) {
                ret = vc4_get_bcl(dev, exec);
                if (ret)

diff --git a/include/uapi/drm/vc4_drm.h b/include/uapi/drm/vc4_drm.h
index b95a0e1..d97065b 100644 (file)
--- a/include/uapi/drm/vc4_drm.h
+++ b/include/uapi/drm/vc4_drm.h
@@ -183,11 +183,10 @@ struct drm_vc4_submit_cl {
        /* ID of the perfmon to attach to this job. 0 means no perfmon. */
        __u32 perfmonid;
 
-       /* Unused field to align this struct on 64 bits. Must be set to 0.
-        * If one ever needs to add an u32 field to this struct, this field
-        * can be used.
+       /* Syncobj handle to wait on. If set, processing of this render job
+        * will not start until the syncobj is signaled. 0 means ignore.
         */
-       __u32 pad2;
+       __u32 in_sync;
 };
 
 /**