[PATCH 1/4] drm/panfrost: Add cycle counter job requirement

alyssa.rosenzweig at collabora.com alyssa.rosenzweig at collabora.com
Thu May 27 20:38:01 UTC 2021


From: Alyssa Rosenzweig <alyssa.rosenzweig at collabora.com>

Extend the Panfrost UABI with a new job requirement for cycle counters
(and GPU timestamps, by extension). This requirement is used in
userspace to implement ARB_shader_clock, an OpenGL extension reporting
the GPU cycle count within a shader. The same mechanism will be required
to implement timestamp queries as a "write value - timestamp" job.

We cannot enable cycle counters unconditionally, as enabling them
increases GPU power consumption. They should be left off unless actually
required by the application for profiling purposes.

Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig at collabora.com>
---
 include/uapi/drm/panfrost_drm.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/include/uapi/drm/panfrost_drm.h b/include/uapi/drm/panfrost_drm.h
index ec19db1ee..27e6cb941 100644
--- a/include/uapi/drm/panfrost_drm.h
+++ b/include/uapi/drm/panfrost_drm.h
@@ -39,7 +39,8 @@ extern "C" {
 #define DRM_IOCTL_PANFROST_PERFCNT_ENABLE	DRM_IOW(DRM_COMMAND_BASE + DRM_PANFROST_PERFCNT_ENABLE, struct drm_panfrost_perfcnt_enable)
 #define DRM_IOCTL_PANFROST_PERFCNT_DUMP		DRM_IOW(DRM_COMMAND_BASE + DRM_PANFROST_PERFCNT_DUMP, struct drm_panfrost_perfcnt_dump)
 
-#define PANFROST_JD_REQ_FS (1 << 0)
+#define PANFROST_JD_REQ_FS			(1 << 0)
+#define PANFROST_JD_REQ_PERMON			(1 << 1)
 /**
  * struct drm_panfrost_submit - ioctl argument for submitting commands to the 3D
  * engine.
-- 
2.30.2



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