tools/power/x86/intel-speed-select: Avoid setting duplicate tdp level

If the new TDP level requetsted is same as the current TDP level, don't
call into driver to change level.
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
[srinivas.pandruvada@linux.intel.com: changelog edits]
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>

tools/power/x86/intel-speed-select/isst-config.c

@@ -1229,16 +1229,30 @@ static void adjust_scaling_max_from_base_freq(int cpu);
 static void set_tdp_level_for_cpu(struct isst_id *id, void *arg1, void *arg2, void *arg3,
 				  void *arg4)
 {
+	struct isst_pkg_ctdp pkg_dev;
 	int ret;
 
+	ret = isst_get_ctdp_levels(id, &pkg_dev);
+	if (ret) {
+		isst_display_error_info_message(1, "Get TDP level failed", 0, 0);
+		isst_ctdp_display_information_end(outf);
+		exit(1);
+	}
+
+	if (pkg_dev.current_level == tdp_level) {
+		debug_printf("TDP level already set. Skipped\n");
+		goto display_result;
+	}
+
 	ret = isst_set_tdp_level(id, tdp_level);
 	if (ret) {
 		isst_display_error_info_message(1, "Set TDP level failed", 0, 0);
 		isst_ctdp_display_information_end(outf);
 		exit(1);
-	} else {
-		isst_display_result(id, outf, "perf-profile", "set_tdp_level",
-				    ret);
+	}
+
+display_result:
+	isst_display_result(id, outf, "perf-profile", "set_tdp_level", ret);
 	if (force_online_offline) {
 		struct isst_pkg_ctdp_level_info ctdp_level;
 
@@ -1272,7 +1286,6 @@ static void set_tdp_level_for_cpu(struct isst_id *id, void *arg1, void *arg2, vo
 			}
 		}
 	}
-	}
 }
 
 static void set_tdp_level(int arg)