drm/etnaviv: submit support for out-fences

Based on commit 4cd0945901a6 ("drm/msm: submit support for out-fences").
We increment the minor driver version so userspace can detect explicit
fence support.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
---
v3: Changed to work with fence returned from GPU submit.

drivers/gpu/drm/etnaviv/etnaviv_drv.c

@@ -512,7 +512,7 @@ static struct drm_driver etnaviv_drm_driver = {
 	.desc               = "etnaviv DRM",
 	.date               = "20151214",
 	.major              = 1,
-	.minor              = 0,
+	.minor              = 1,
 };
 
 /*

drivers/gpu/drm/etnaviv/etnaviv_gem_submit.c

@@ -309,6 +309,8 @@ int etnaviv_ioctl_gem_submit(struct drm_device *dev, void *data,
 	struct etnaviv_cmdbuf *cmdbuf;
 	struct etnaviv_gpu *gpu;
 	struct dma_fence *in_fence = NULL;
+	struct sync_file *sync_file = NULL;
+	int out_fence_fd = -1;
 	void *stream;
 	int ret;
 
@@ -376,6 +378,14 @@ int etnaviv_ioctl_gem_submit(struct drm_device *dev, void *data,
 		goto err_submit_cmds;
 	}
 
+	if (args->flags & ETNA_SUBMIT_FENCE_FD_OUT) {
+		out_fence_fd = get_unused_fd_flags(O_CLOEXEC);
+		if (out_fence_fd < 0) {
+			ret = out_fence_fd;
+			goto err_submit_cmds;
+		}
+	}
+
 	submit = submit_create(dev, gpu, args->nr_bos);
 	if (!submit) {
 		ret = -ENOMEM;
@@ -436,6 +446,22 @@ int etnaviv_ioctl_gem_submit(struct drm_device *dev, void *data,
 	if (ret == 0)
 		cmdbuf = NULL;
 
+	if (args->flags & ETNA_SUBMIT_FENCE_FD_OUT) {
+		/*
+		 * This can be improved: ideally we want to allocate the sync
+		 * file before kicking off the GPU job and just attach the
+		 * fence to the sync file here, eliminating the ENOMEM
+		 * possibility at this stage.
+		 */
+		sync_file = sync_file_create(submit->fence);
+		if (!sync_file) {
+			ret = -ENOMEM;
+			goto out;
+		}
+		fd_install(out_fence_fd, sync_file->file);
+	}
+
+	args->fence_fd = out_fence_fd;
 	args->fence = submit->fence->seqno;
 
 out:
@@ -455,6 +481,8 @@ err_submit_objects:
 	submit_cleanup(submit);
 
 err_submit_cmds:
+	if (ret && (out_fence_fd >= 0))
+		put_unused_fd(out_fence_fd);
 	/* if we still own the cmdbuf */
 	if (cmdbuf)
 		etnaviv_cmdbuf_free(cmdbuf);

include/uapi/drm/etnaviv_drm.h

@@ -156,8 +156,10 @@ struct drm_etnaviv_gem_submit_bo {
  */
 #define ETNA_SUBMIT_NO_IMPLICIT         0x0001
 #define ETNA_SUBMIT_FENCE_FD_IN         0x0002
+#define ETNA_SUBMIT_FENCE_FD_OUT        0x0004
 #define ETNA_SUBMIT_FLAGS		(ETNA_SUBMIT_NO_IMPLICIT | \
-					 ETNA_SUBMIT_FENCE_FD_IN)
+					 ETNA_SUBMIT_FENCE_FD_IN | \
+					 ETNA_SUBMIT_FENCE_FD_OUT)
 #define ETNA_PIPE_3D      0x00
 #define ETNA_PIPE_2D      0x01
 #define ETNA_PIPE_VG      0x02
@@ -172,7 +174,7 @@ struct drm_etnaviv_gem_submit {
 	__u64 relocs;         /* in, ptr to array of submit_reloc's */
 	__u64 stream;         /* in, ptr to cmdstream */
 	__u32 flags;          /* in, mask of ETNA_SUBMIT_x */
-	__s32 fence_fd;       /* in, fence fd (see ETNA_SUBMIT_FENCE_FD_IN) */
+	__s32 fence_fd;       /* in/out, fence fd (see ETNA_SUBMIT_FENCE_FD_x) */
 };
 
 /* The normal way to synchronize with the GPU is just to CPU_PREP on