drm/amdgpu/UAPI: add new CTX OP to get/set stable pstates

Add a new CTX ioctl operation to set stable pstates for profiling.
When creating traces for tools like RGP or using SPM or doing
performance profiling, it's required to enable a special
stable profiling power state on the GPU.  These profiling
states set fixed clocks and disable certain other power
features like powergating which may impact the results.

Historically, these profiling pstates were enabled via sysfs,
but this adds an interface to enable it via the CTX ioctl
from the application.  Since the power state is global
only one application can set it at a time, so if multiple
applications try and use it only the first will get it,
the ioctl will return -EBUSY for others.  The sysfs interface
will override whatever has been set by this interface.

Mesa MR: https://gitlab.freedesktop.org/mesa/drm/-/merge_requests/207

v2: don't default r = 0;
v3: rebase on Evan's PM cleanup

Reviewed-by: Evan Quan <evan.quan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/pm/inc/amdgpu_dpm.h b/drivers/gpu/drm/amd/pm/inc/amdgpu_dpm.h
index 2766b88ecf96..5cc05110cdae 100644
--- a/drivers/gpu/drm/amd/pm/inc/amdgpu_dpm.h
+++ b/drivers/gpu/drm/amd/pm/inc/amdgpu_dpm.h
@@ -338,6 +338,9 @@ struct amdgpu_pm {
 	uint32_t		smu_debug_mask;
 
 	bool			pp_force_state_enabled;
+
+	struct mutex            stable_pstate_ctx_lock;
+	struct amdgpu_ctx       *stable_pstate_ctx;
 };
 
 u32 amdgpu_dpm_get_vblank_time(struct amdgpu_device *adev);