[Intel-gfx] [PATCH 07/12] lib/igt_kms: Add support for the OUT_FENCE_PTR property

[Chris Wilson]

On Tue, Nov 22, 2016 at 10:53:51AM +0000, Brian Starkey wrote:
> Hi Gustavo,
> 
> A little late to the party here, but I was blocked by our internal
> contributions process...
> 
> I didn't see these end up in my checkout yet though, so I guess they
> aren't picked up yet.
> 
> On Mon, Nov 14, 2016 at 06:59:21PM +0900, Gustavo Padovan wrote:
> >From: Gustavo Padovan <gustavo.padovan at collabora.co.uk>
> >
> >Add support for the OUT_FENCE_PTR property to enable setting out fences for
> >atomic commits.
> >
> >Signed-off-by: Gustavo Padovan <gustavo.padovan at collabora.co.uk>
> >---
> >lib/igt_kms.c | 20 +++++++++++++++++++-
> >lib/igt_kms.h |  3 +++
> >2 files changed, 22 insertions(+), 1 deletion(-)
> >
> >diff --git a/lib/igt_kms.c b/lib/igt_kms.c
> >index 4748c0a..f25e1eb 100644
> >--- a/lib/igt_kms.c
> >+++ b/lib/igt_kms.c
> >@@ -175,7 +175,8 @@ const char *igt_crtc_prop_names[IGT_NUM_CRTC_PROPS] = {
> >	"DEGAMMA_LUT",
> >	"GAMMA_LUT",
> >	"MODE_ID",
> >-	"ACTIVE"
> >+	"ACTIVE",
> >+	"OUT_FENCE_PTR"
> >};
> >
> >const char *igt_connector_prop_names[IGT_NUM_CONNECTOR_PROPS] = {
> >@@ -2103,6 +2104,9 @@ static void igt_atomic_prepare_crtc_commit(igt_pipe_t *pipe_obj, drmModeAtomicRe
> >		igt_atomic_populate_crtc_req(req, pipe_obj, IGT_CRTC_ACTIVE, !!output);
> >	}
> >
> >+	if (pipe_obj->out_fence_ptr)
> >+		igt_atomic_populate_crtc_req(req, pipe_obj, IGT_CRTC_OUT_FENCE_PTR, pipe_obj->out_fence_ptr);
> >+
> >	/*
> >	 *	TODO: Add all crtc level properties here
> >	 */
> >@@ -2683,6 +2687,20 @@ igt_pipe_set_gamma_lut(igt_pipe_t *pipe, void *ptr, size_t length)
> >}
> >
> >/**
> >+ * igt_pipe_set_out_fence_ptr:
> >+ * @pipe: pipe pointer to which background color to be set
> >+ * @fence_ptr: out fence pointer
> 
> I don't think fence_ptr can be int *. It needs to be a pointer to a
> 64-bit type.
> 
> >+ *
> >+ * Sets the out fence pointer that will be passed to the kernel in
> >+ * the atomic ioctl. When the kernel returns the out fence pointer
> >+ * will contain the fd number of the out fence created by KMS.
> >+ */
> >+void igt_pipe_set_out_fence_ptr(igt_pipe_t *pipe, int *fence_ptr)
> >+{
> >+	pipe->out_fence_ptr = (uint64_t) fence_ptr;
> >+}
> >+
> >+/**
> > * igt_crtc_set_background:
> > * @pipe: pipe pointer to which background color to be set
> > * @background: background color value in BGR 16bpc
> >diff --git a/lib/igt_kms.h b/lib/igt_kms.h
> >index 344f931..02d7bd1 100644
> >--- a/lib/igt_kms.h
> >+++ b/lib/igt_kms.h
> >@@ -110,6 +110,7 @@ enum igt_atomic_crtc_properties {
> >       IGT_CRTC_GAMMA_LUT,
> >       IGT_CRTC_MODE_ID,
> >       IGT_CRTC_ACTIVE,
> >+       IGT_CRTC_OUT_FENCE_PTR,
> >       IGT_NUM_CRTC_PROPS
> >};
> >
> >@@ -298,6 +299,7 @@ struct igt_pipe {
> >
> >	uint64_t mode_blob;
> >	bool mode_changed;
> >+	uint64_t out_fence_ptr;
> 
> IMO this should be:
> 
> 	int64_t *out_fence_ptr;

In userspace, fences are *fd*, a plain int. It is only the uabi that we
pass pointers as u64 to the kernel, and indeed that should be limited to
the uabi wrapper.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre