[PATCH v2 1/3] drm/amd/display: Add module parameter for freesync video mode

[Aurabindo Pillai]

[Why&How]
Adds a module parameter to enable experimental freesync video mode modeset
optimization. Enabling this mode allows the driver to skip a full modeset when
freesync compatible modes are requested by the userspace. This paramters also
adds some standard modes based on the connected monitor's VRR range.

Signed-off-by: Aurabindo Pillai <aurabindo.pillai at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu.h     |  1 +
 drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 12 ++++++++++++
 2 files changed, 13 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
index 83ac06a3ec05..efbfee93c359 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
@@ -177,6 +177,7 @@ extern int amdgpu_gpu_recovery;
 extern int amdgpu_emu_mode;
 extern uint amdgpu_smu_memory_pool_size;
 extern uint amdgpu_dc_feature_mask;
+extern uint amdgpu_exp_freesync_vid_mode;
 extern uint amdgpu_dc_debug_mask;
 extern uint amdgpu_dm_abm_level;
 extern struct amdgpu_mgpu_info mgpu_info;
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
index b2a1dd7581bf..ece51ecd53d1 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
@@ -158,6 +158,7 @@ int amdgpu_mes;
 int amdgpu_noretry = -1;
 int amdgpu_force_asic_type = -1;
 int amdgpu_tmz;
+uint amdgpu_exp_freesync_vid_mode;
 int amdgpu_reset_method = -1; /* auto */
 int amdgpu_num_kcq = -1;
 
@@ -786,6 +787,17 @@ module_param_named(abmlevel, amdgpu_dm_abm_level, uint, 0444);
 MODULE_PARM_DESC(tmz, "Enable TMZ feature (-1 = auto, 0 = off (default), 1 = on)");
 module_param_named(tmz, amdgpu_tmz, int, 0444);
 
+/**
+ * DOC: experimental_freesync_video (uint)
+ * Enabled the optimization to adjust front porch timing to achieve seamless mode change experience
+ * when setting a freesync supported mode for which full modeset is not needed.
+ * The default value: 0 (off).
+ */
+MODULE_PARM_DESC(
+	experimental_freesync_video,
+	"Enable freesync modesetting optimization feature (0 = off (default), 1 = on)");
+module_param_named(experimental_freesync_video, amdgpu_exp_freesync_vid_mode, uint, 0444);
+
 /**
  * DOC: reset_method (int)
  * GPU reset method (-1 = auto (default), 0 = legacy, 1 = mode0, 2 = mode1, 3 = mode2, 4 = baco)
-- 
2.25.1