diff mbox

[i-g-t,1/6] lib/igt_kms: Add writeback support in lib/

Message ID 20180301173832.9654-2-liviu.dudau@arm.com (mailing list archive)
State New, archived
Headers show

Commit Message

Liviu Dudau March 1, 2018, 5:38 p.m. UTC 
From: Brian Starkey <brian.starkey@arm.com>

Add support in igt_kms for Writeback connectors, with the ability to
attach framebuffers and retrieve fences.

Signed-off-by: Brian Starkey <brian.starkey@arm.com>
---
 lib/igt_kms.c | 72 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
 lib/igt_kms.h | 14 ++++++++++++
 2 files changed, 85 insertions(+), 1 deletion(-)

Comments

Maarten Lankhorst June 25, 2018, 12:19 p.m. UTC | #1 
Op 01-03-18 om 18:38 schreef Liviu Dudau:
> From: Brian Starkey <brian.starkey@arm.com>
>
> Add support in igt_kms for Writeback connectors, with the ability to
> attach framebuffers and retrieve fences.
>
> Signed-off-by: Brian Starkey <brian.starkey@arm.com>
> ---
>  lib/igt_kms.c | 72 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
>  lib/igt_kms.h | 14 ++++++++++++
>  2 files changed, 85 insertions(+), 1 deletion(-)
>
> diff --git a/lib/igt_kms.c b/lib/igt_kms.c
> index 022abfe7..00d9d2e2 100644
> --- a/lib/igt_kms.c
> +++ b/lib/igt_kms.c
> @@ -190,7 +190,10 @@ const char *igt_connector_prop_names[IGT_NUM_CONNECTOR_PROPS] = {
>  	"scaling mode",
>  	"CRTC_ID",
>  	"DPMS",
> -	"Broadcast RGB"
> +	"Broadcast RGB",
> +	"WRITEBACK_PIXEL_FORMATS",
> +	"WRITEBACK_FB_ID",
> +	"WRITEBACK_OUT_FENCE_PTR"
>  };
>  
>  /*
> @@ -452,6 +455,7 @@ static const struct type_name connector_type_names[] = {
>  	{ DRM_MODE_CONNECTOR_VIRTUAL, "Virtual" },
>  	{ DRM_MODE_CONNECTOR_DSI, "DSI" },
>  	{ DRM_MODE_CONNECTOR_DPI, "DPI" },
> +	{ DRM_MODE_CONNECTOR_WRITEBACK, "Writeback" },
>  	{}
>  };
>  
> @@ -1947,6 +1951,7 @@ void igt_display_init(igt_display_t *display, int drm_fd)
>  		output->force_reprobe = true;
>  		output->id = resources->connectors[i];
>  		output->display = display;
> +		output->writeback_out_fence_fd = -1;
>  
>  		igt_output_refresh(output);
>  	}
> @@ -2040,6 +2045,43 @@ igt_output_t *igt_output_from_connector(igt_display_t *display,
>  	return found;
>  }
>  
> +void igt_output_set_writeback_fb(igt_output_t *output, struct igt_fb *fb)
> +{
> +	igt_display_t *display = output->display;
> +	struct kmstest_connector_config *config = &output->config;
> +
> +	if (config->connector->connector_type != DRM_MODE_CONNECTOR_WRITEBACK)
> +		return;

igt_output_set_prop_value(output, IGT_CONNECTOR_WRITEBACK_FB_ID, ...);

As a bonus you don't need to check for WRITEBACK type, because this property will be undefined and commit will fail.

> +	LOG(display, "%s: output_set_writeback_fb(%d)\n", output->name,
> +	    fb ? fb->fb_id : 0);
> +
> +	output->writeback_fb = fb;
> +}
Probably want to merge this with igt_output_request_writeback_out_fence(), else there's no point for the convenience function. :)

> +static void igt_output_reset_writeback_out_fence(igt_output_t *output)
> +{
> +	if (output->writeback_out_fence_fd >= 0) {
> +		close(output->writeback_out_fence_fd);
> +		output->writeback_out_fence_fd = -1;
> +	}
> +}
> +
> +void igt_output_request_writeback_out_fence(igt_output_t *output)
> +{
> +	igt_output_reset_writeback_out_fence(output);
> +	igt_output_set_prop_value(output, IGT_CONNECTOR_WRITEBACK_OUT_FENCE_PTR,
> +				  (ptrdiff_t)&output->writeback_out_fence_fd);
> +}
> +
> +int igt_output_get_last_writeback_out_fence(igt_output_t *output)
> +{
> +	int fd = output->writeback_out_fence_fd;
> +	output->writeback_out_fence_fd = -1;
> +
> +	return fd;
> +}
Please handle this the same we do for pipe_obj->out_fence_fd.. No need to do it differently.
> +
>  static void igt_pipe_fini(igt_pipe_t *pipe)
>  {
>  	int i;
> @@ -2063,6 +2105,8 @@ static void igt_pipe_fini(igt_pipe_t *pipe)
>  static void igt_output_fini(igt_output_t *output)
>  {
>  	kmstest_free_connector_config(&output->config);
> +	if (output->writeback_out_fence_fd >= 0)
> +		close(output->writeback_out_fence_fd);
>  	free(output->name);
>  	output->name = NULL;
>  }
> @@ -2879,6 +2923,31 @@ static void igt_atomic_prepare_connector_commit(igt_output_t *output, drmModeAto
>  					  output->props[i],
>  					  output->values[i]));
>  	}
> +
> +	if (output->writeback_fb)
> +		output->writeback_fb = NULL;
> +
> +	igt_output_reset_writeback_out_fence(output);
> +}
> +
> +static void handle_writeback_out_fences(igt_display_t *display, uint32_t flags, int ret)
> +{
> +	int i;
> +
> +	for (i = 0; i < display->n_outputs; i++) {
> +		igt_output_t *output = &display->outputs[i];
> +
> +		if (!output->config.connector)
> +			continue;
> +
> +		if (!igt_output_is_prop_changed(output, IGT_CONNECTOR_WRITEBACK_OUT_FENCE_PTR))
> +			continue;
> +
> +		igt_output_clear_prop_changed(output, IGT_CONNECTOR_WRITEBACK_OUT_FENCE_PTR);
> +
> +		if (ret || (flags & DRM_MODE_ATOMIC_TEST_ONLY))
> +			igt_assert(output->writeback_out_fence_fd == -1);
> +	}
>  }
>  
>  /*
> @@ -2929,6 +2998,7 @@ static int igt_atomic_commit(igt_display_t *display, uint32_t flags, void *user_
>  	}
>  
>  	ret = drmModeAtomicCommit(display->drm_fd, req, flags, user_data);
> +	handle_writeback_out_fences(display, flags, ret);
>  
>  	drmModeAtomicFree(req);
>  	return ret;
> diff --git a/lib/igt_kms.h b/lib/igt_kms.h
> index 1c46186e..59ccc4c6 100644
> --- a/lib/igt_kms.h
> +++ b/lib/igt_kms.h
> @@ -38,6 +38,10 @@
>  #include "igt_fb.h"
>  #include "ioctl_wrappers.h"
>  
> +#ifndef DRM_MODE_CONNECTOR_WRITEBACK
> +#define DRM_MODE_CONNECTOR_WRITEBACK   18
> +#endif
> +
>  /* Low-level helpers with kmstest_ prefix */
>  
>  /**
> @@ -120,6 +124,9 @@ enum igt_atomic_connector_properties {
>         IGT_CONNECTOR_CRTC_ID,
>         IGT_CONNECTOR_DPMS,
>         IGT_CONNECTOR_BROADCAST_RGB,
> +       IGT_CONNECTOR_WRITEBACK_PIXEL_FORMATS,
> +       IGT_CONNECTOR_WRITEBACK_FB_ID,
> +       IGT_CONNECTOR_WRITEBACK_OUT_FENCE_PTR,
>         IGT_NUM_CONNECTOR_PROPS
>  };
>  
> @@ -345,6 +352,9 @@ typedef struct {
>  
>  	uint32_t props[IGT_NUM_CONNECTOR_PROPS];
>  	uint64_t values[IGT_NUM_CONNECTOR_PROPS];
> +
> +	struct igt_fb *writeback_fb;
I've spent a lot of effort into making sure we can set any property directly. Please don't add this struct member here,
there's no need for it.
> +	int32_t writeback_out_fence_fd;
>  } igt_output_t;
>  
>  struct igt_display {
> @@ -380,6 +390,10 @@ igt_plane_t *igt_output_get_plane(igt_output_t *output, int plane_idx);
>  igt_plane_t *igt_output_get_plane_type(igt_output_t *output, int plane_type);
>  igt_output_t *igt_output_from_connector(igt_display_t *display,
>      drmModeConnector *connector);
> +void igt_output_set_writeback_fb(igt_output_t *output, struct igt_fb *fb);
> +void igt_output_request_writeback_out_fence(igt_output_t *output);
> +int igt_output_get_last_writeback_out_fence(igt_output_t *output);
> +
>  igt_plane_t *igt_pipe_get_plane_type(igt_pipe_t *pipe, int plane_type);
>  
>  void igt_pipe_request_out_fence(igt_pipe_t *pipe);
Liviu Dudau June 26, 2018, 8:28 a.m. UTC | #2 
Hi Maarten,

Thanks for reviewing this! As this patch is quite old, I agree that it
needs a refresh in order to catch up with the latest igt. I will take
your feedback and come up with an update in the near future.

Best regards,
Liviu

On Mon, Jun 25, 2018 at 02:19:46PM +0200, Maarten Lankhorst wrote:
> Op 01-03-18 om 18:38 schreef Liviu Dudau:
> > From: Brian Starkey <brian.starkey@arm.com>
> >
> > Add support in igt_kms for Writeback connectors, with the ability to
> > attach framebuffers and retrieve fences.
> >
> > Signed-off-by: Brian Starkey <brian.starkey@arm.com>
> > ---
> >  lib/igt_kms.c | 72 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
> >  lib/igt_kms.h | 14 ++++++++++++
> >  2 files changed, 85 insertions(+), 1 deletion(-)
> >
> > diff --git a/lib/igt_kms.c b/lib/igt_kms.c
> > index 022abfe7..00d9d2e2 100644
> > --- a/lib/igt_kms.c
> > +++ b/lib/igt_kms.c
> > @@ -190,7 +190,10 @@ const char *igt_connector_prop_names[IGT_NUM_CONNECTOR_PROPS] = {
> >  	"scaling mode",
> >  	"CRTC_ID",
> >  	"DPMS",
> > -	"Broadcast RGB"
> > +	"Broadcast RGB",
> > +	"WRITEBACK_PIXEL_FORMATS",
> > +	"WRITEBACK_FB_ID",
> > +	"WRITEBACK_OUT_FENCE_PTR"
> >  };
> >  
> >  /*
> > @@ -452,6 +455,7 @@ static const struct type_name connector_type_names[] = {
> >  	{ DRM_MODE_CONNECTOR_VIRTUAL, "Virtual" },
> >  	{ DRM_MODE_CONNECTOR_DSI, "DSI" },
> >  	{ DRM_MODE_CONNECTOR_DPI, "DPI" },
> > +	{ DRM_MODE_CONNECTOR_WRITEBACK, "Writeback" },
> >  	{}
> >  };
> >  
> > @@ -1947,6 +1951,7 @@ void igt_display_init(igt_display_t *display, int drm_fd)
> >  		output->force_reprobe = true;
> >  		output->id = resources->connectors[i];
> >  		output->display = display;
> > +		output->writeback_out_fence_fd = -1;
> >  
> >  		igt_output_refresh(output);
> >  	}
> > @@ -2040,6 +2045,43 @@ igt_output_t *igt_output_from_connector(igt_display_t *display,
> >  	return found;
> >  }
> >  
> > +void igt_output_set_writeback_fb(igt_output_t *output, struct igt_fb *fb)
> > +{
> > +	igt_display_t *display = output->display;
> > +	struct kmstest_connector_config *config = &output->config;
> > +
> > +	if (config->connector->connector_type != DRM_MODE_CONNECTOR_WRITEBACK)
> > +		return;
> 
> igt_output_set_prop_value(output, IGT_CONNECTOR_WRITEBACK_FB_ID, ...);
> 
> As a bonus you don't need to check for WRITEBACK type, because this property will be undefined and commit will fail.
> 
> > +	LOG(display, "%s: output_set_writeback_fb(%d)\n", output->name,
> > +	    fb ? fb->fb_id : 0);
> > +
> > +	output->writeback_fb = fb;
> > +}
> Probably want to merge this with igt_output_request_writeback_out_fence(), else there's no point for the convenience function. :)
> 
> > +static void igt_output_reset_writeback_out_fence(igt_output_t *output)
> > +{
> > +	if (output->writeback_out_fence_fd >= 0) {
> > +		close(output->writeback_out_fence_fd);
> > +		output->writeback_out_fence_fd = -1;
> > +	}
> > +}
> > +
> > +void igt_output_request_writeback_out_fence(igt_output_t *output)
> > +{
> > +	igt_output_reset_writeback_out_fence(output);
> > +	igt_output_set_prop_value(output, IGT_CONNECTOR_WRITEBACK_OUT_FENCE_PTR,
> > +				  (ptrdiff_t)&output->writeback_out_fence_fd);
> > +}
> > +
> > +int igt_output_get_last_writeback_out_fence(igt_output_t *output)
> > +{
> > +	int fd = output->writeback_out_fence_fd;
> > +	output->writeback_out_fence_fd = -1;
> > +
> > +	return fd;
> > +}
> Please handle this the same we do for pipe_obj->out_fence_fd.. No need to do it differently.
> > +
> >  static void igt_pipe_fini(igt_pipe_t *pipe)
> >  {
> >  	int i;
> > @@ -2063,6 +2105,8 @@ static void igt_pipe_fini(igt_pipe_t *pipe)
> >  static void igt_output_fini(igt_output_t *output)
> >  {
> >  	kmstest_free_connector_config(&output->config);
> > +	if (output->writeback_out_fence_fd >= 0)
> > +		close(output->writeback_out_fence_fd);
> >  	free(output->name);
> >  	output->name = NULL;
> >  }
> > @@ -2879,6 +2923,31 @@ static void igt_atomic_prepare_connector_commit(igt_output_t *output, drmModeAto
> >  					  output->props[i],
> >  					  output->values[i]));
> >  	}
> > +
> > +	if (output->writeback_fb)
> > +		output->writeback_fb = NULL;
> > +
> > +	igt_output_reset_writeback_out_fence(output);
> > +}
> > +
> > +static void handle_writeback_out_fences(igt_display_t *display, uint32_t flags, int ret)
> > +{
> > +	int i;
> > +
> > +	for (i = 0; i < display->n_outputs; i++) {
> > +		igt_output_t *output = &display->outputs[i];
> > +
> > +		if (!output->config.connector)
> > +			continue;
> > +
> > +		if (!igt_output_is_prop_changed(output, IGT_CONNECTOR_WRITEBACK_OUT_FENCE_PTR))
> > +			continue;
> > +
> > +		igt_output_clear_prop_changed(output, IGT_CONNECTOR_WRITEBACK_OUT_FENCE_PTR);
> > +
> > +		if (ret || (flags & DRM_MODE_ATOMIC_TEST_ONLY))
> > +			igt_assert(output->writeback_out_fence_fd == -1);
> > +	}
> >  }
> >  
> >  /*
> > @@ -2929,6 +2998,7 @@ static int igt_atomic_commit(igt_display_t *display, uint32_t flags, void *user_
> >  	}
> >  
> >  	ret = drmModeAtomicCommit(display->drm_fd, req, flags, user_data);
> > +	handle_writeback_out_fences(display, flags, ret);
> >  
> >  	drmModeAtomicFree(req);
> >  	return ret;
> > diff --git a/lib/igt_kms.h b/lib/igt_kms.h
> > index 1c46186e..59ccc4c6 100644
> > --- a/lib/igt_kms.h
> > +++ b/lib/igt_kms.h
> > @@ -38,6 +38,10 @@
> >  #include "igt_fb.h"
> >  #include "ioctl_wrappers.h"
> >  
> > +#ifndef DRM_MODE_CONNECTOR_WRITEBACK
> > +#define DRM_MODE_CONNECTOR_WRITEBACK   18
> > +#endif
> > +
> >  /* Low-level helpers with kmstest_ prefix */
> >  
> >  /**
> > @@ -120,6 +124,9 @@ enum igt_atomic_connector_properties {
> >         IGT_CONNECTOR_CRTC_ID,
> >         IGT_CONNECTOR_DPMS,
> >         IGT_CONNECTOR_BROADCAST_RGB,
> > +       IGT_CONNECTOR_WRITEBACK_PIXEL_FORMATS,
> > +       IGT_CONNECTOR_WRITEBACK_FB_ID,
> > +       IGT_CONNECTOR_WRITEBACK_OUT_FENCE_PTR,
> >         IGT_NUM_CONNECTOR_PROPS
> >  };
> >  
> > @@ -345,6 +352,9 @@ typedef struct {
> >  
> >  	uint32_t props[IGT_NUM_CONNECTOR_PROPS];
> >  	uint64_t values[IGT_NUM_CONNECTOR_PROPS];
> > +
> > +	struct igt_fb *writeback_fb;
> I've spent a lot of effort into making sure we can set any property directly. Please don't add this struct member here,
> there's no need for it.
> > +	int32_t writeback_out_fence_fd;
> >  } igt_output_t;
> >  
> >  struct igt_display {
> > @@ -380,6 +390,10 @@ igt_plane_t *igt_output_get_plane(igt_output_t *output, int plane_idx);
> >  igt_plane_t *igt_output_get_plane_type(igt_output_t *output, int plane_type);
> >  igt_output_t *igt_output_from_connector(igt_display_t *display,
> >      drmModeConnector *connector);
> > +void igt_output_set_writeback_fb(igt_output_t *output, struct igt_fb *fb);
> > +void igt_output_request_writeback_out_fence(igt_output_t *output);
> > +int igt_output_get_last_writeback_out_fence(igt_output_t *output);
> > +
> >  igt_plane_t *igt_pipe_get_plane_type(igt_pipe_t *pipe, int plane_type);
> >  
> >  void igt_pipe_request_out_fence(igt_pipe_t *pipe);
> 
>
diff mbox

Patch

diff --git a/lib/igt_kms.c b/lib/igt_kms.c
index 022abfe7..00d9d2e2 100644
--- a/lib/igt_kms.c
+++ b/lib/igt_kms.c
@@ -190,7 +190,10 @@  const char *igt_connector_prop_names[IGT_NUM_CONNECTOR_PROPS] = {
 	"scaling mode",
 	"CRTC_ID",
 	"DPMS",
-	"Broadcast RGB"
+	"Broadcast RGB",
+	"WRITEBACK_PIXEL_FORMATS",
+	"WRITEBACK_FB_ID",
+	"WRITEBACK_OUT_FENCE_PTR"
 };
 
 /*
@@ -452,6 +455,7 @@  static const struct type_name connector_type_names[] = {
 	{ DRM_MODE_CONNECTOR_VIRTUAL, "Virtual" },
 	{ DRM_MODE_CONNECTOR_DSI, "DSI" },
 	{ DRM_MODE_CONNECTOR_DPI, "DPI" },
+	{ DRM_MODE_CONNECTOR_WRITEBACK, "Writeback" },
 	{}
 };
 
@@ -1947,6 +1951,7 @@  void igt_display_init(igt_display_t *display, int drm_fd)
 		output->force_reprobe = true;
 		output->id = resources->connectors[i];
 		output->display = display;
+		output->writeback_out_fence_fd = -1;
 
 		igt_output_refresh(output);
 	}
@@ -2040,6 +2045,43 @@  igt_output_t *igt_output_from_connector(igt_display_t *display,
 	return found;
 }
 
+void igt_output_set_writeback_fb(igt_output_t *output, struct igt_fb *fb)
+{
+	igt_display_t *display = output->display;
+	struct kmstest_connector_config *config = &output->config;
+
+	if (config->connector->connector_type != DRM_MODE_CONNECTOR_WRITEBACK)
+		return;
+
+	LOG(display, "%s: output_set_writeback_fb(%d)\n", output->name,
+	    fb ? fb->fb_id : 0);
+
+	output->writeback_fb = fb;
+}
+
+static void igt_output_reset_writeback_out_fence(igt_output_t *output)
+{
+	if (output->writeback_out_fence_fd >= 0) {
+		close(output->writeback_out_fence_fd);
+		output->writeback_out_fence_fd = -1;
+	}
+}
+
+void igt_output_request_writeback_out_fence(igt_output_t *output)
+{
+	igt_output_reset_writeback_out_fence(output);
+	igt_output_set_prop_value(output, IGT_CONNECTOR_WRITEBACK_OUT_FENCE_PTR,
+				  (ptrdiff_t)&output->writeback_out_fence_fd);
+}
+
+int igt_output_get_last_writeback_out_fence(igt_output_t *output)
+{
+	int fd = output->writeback_out_fence_fd;
+	output->writeback_out_fence_fd = -1;
+
+	return fd;
+}
+
 static void igt_pipe_fini(igt_pipe_t *pipe)
 {
 	int i;
@@ -2063,6 +2105,8 @@  static void igt_pipe_fini(igt_pipe_t *pipe)
 static void igt_output_fini(igt_output_t *output)
 {
 	kmstest_free_connector_config(&output->config);
+	if (output->writeback_out_fence_fd >= 0)
+		close(output->writeback_out_fence_fd);
 	free(output->name);
 	output->name = NULL;
 }
@@ -2879,6 +2923,31 @@  static void igt_atomic_prepare_connector_commit(igt_output_t *output, drmModeAto
 					  output->props[i],
 					  output->values[i]));
 	}
+
+	if (output->writeback_fb)
+		output->writeback_fb = NULL;
+
+	igt_output_reset_writeback_out_fence(output);
+}
+
+static void handle_writeback_out_fences(igt_display_t *display, uint32_t flags, int ret)
+{
+	int i;
+
+	for (i = 0; i < display->n_outputs; i++) {
+		igt_output_t *output = &display->outputs[i];
+
+		if (!output->config.connector)
+			continue;
+
+		if (!igt_output_is_prop_changed(output, IGT_CONNECTOR_WRITEBACK_OUT_FENCE_PTR))
+			continue;
+
+		igt_output_clear_prop_changed(output, IGT_CONNECTOR_WRITEBACK_OUT_FENCE_PTR);
+
+		if (ret || (flags & DRM_MODE_ATOMIC_TEST_ONLY))
+			igt_assert(output->writeback_out_fence_fd == -1);
+	}
 }
 
 /*
@@ -2929,6 +2998,7 @@  static int igt_atomic_commit(igt_display_t *display, uint32_t flags, void *user_
 	}
 
 	ret = drmModeAtomicCommit(display->drm_fd, req, flags, user_data);
+	handle_writeback_out_fences(display, flags, ret);
 
 	drmModeAtomicFree(req);
 	return ret;
diff --git a/lib/igt_kms.h b/lib/igt_kms.h
index 1c46186e..59ccc4c6 100644
--- a/lib/igt_kms.h
+++ b/lib/igt_kms.h
@@ -38,6 +38,10 @@ 
 #include "igt_fb.h"
 #include "ioctl_wrappers.h"
 
+#ifndef DRM_MODE_CONNECTOR_WRITEBACK
+#define DRM_MODE_CONNECTOR_WRITEBACK   18
+#endif
+
 /* Low-level helpers with kmstest_ prefix */
 
 /**
@@ -120,6 +124,9 @@  enum igt_atomic_connector_properties {
        IGT_CONNECTOR_CRTC_ID,
        IGT_CONNECTOR_DPMS,
        IGT_CONNECTOR_BROADCAST_RGB,
+       IGT_CONNECTOR_WRITEBACK_PIXEL_FORMATS,
+       IGT_CONNECTOR_WRITEBACK_FB_ID,
+       IGT_CONNECTOR_WRITEBACK_OUT_FENCE_PTR,
        IGT_NUM_CONNECTOR_PROPS
 };
 
@@ -345,6 +352,9 @@  typedef struct {
 
 	uint32_t props[IGT_NUM_CONNECTOR_PROPS];
 	uint64_t values[IGT_NUM_CONNECTOR_PROPS];
+
+	struct igt_fb *writeback_fb;
+	int32_t writeback_out_fence_fd;
 } igt_output_t;
 
 struct igt_display {
@@ -380,6 +390,10 @@  igt_plane_t *igt_output_get_plane(igt_output_t *output, int plane_idx);
 igt_plane_t *igt_output_get_plane_type(igt_output_t *output, int plane_type);
 igt_output_t *igt_output_from_connector(igt_display_t *display,
     drmModeConnector *connector);
+void igt_output_set_writeback_fb(igt_output_t *output, struct igt_fb *fb);
+void igt_output_request_writeback_out_fence(igt_output_t *output);
+int igt_output_get_last_writeback_out_fence(igt_output_t *output);
+
 igt_plane_t *igt_pipe_get_plane_type(igt_pipe_t *pipe, int plane_type);
 
 void igt_pipe_request_out_fence(igt_pipe_t *pipe);