drm/i915/dsb: Introduce intel_dsb_noop()

Add a helper for emitting a number of DSB NOOPs commands.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230606191504.18099-9-ville.syrjala@linux.intel.com
Reviewed-by: Uma Shankar <uma.shankar@intel.com>

Author: vsyrjala

drivers/gpu/drm/i915/display/intel_dsb.c

@@ -234,6 +234,15 @@ void intel_dsb_reg_write(struct intel_dsb *dsb,
 	}
 }
 
+void intel_dsb_noop(struct intel_dsb *dsb, int count)
+{
+	int i;
+
+	for (i = 0; i < count; i++)
+		intel_dsb_emit(dsb, 0,
+			       DSB_OPCODE_NOOP << DSB_OPCODE_SHIFT);
+}
+
 static void intel_dsb_align_tail(struct intel_dsb *dsb)
 {
 	u32 aligned_tail, tail;

drivers/gpu/drm/i915/display/intel_dsb.h

@@ -19,6 +19,7 @@ void intel_dsb_finish(struct intel_dsb *dsb);
 void intel_dsb_cleanup(struct intel_dsb *dsb);
 void intel_dsb_reg_write(struct intel_dsb *dsb,
 			 i915_reg_t reg, u32 val);
+void intel_dsb_noop(struct intel_dsb *dsb, int count);
 void intel_dsb_commit(struct intel_dsb *dsb,
 		      bool wait_for_vblank);
 void intel_dsb_wait(struct intel_dsb *dsb);