drm/amd/powerplay: show gpu load when print gpu performance for Cz. (v2)

BugLink: http://bugs.launchpad.net/bugs/1546572

Show GPU load in in the debugfs output.

v2: integrate Tom's optimization
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
(cherry picked from commit 605ed219)
Signed-off-by: Alberto Milone <alberto.milone@canonical.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>

drivers/gpu/drm/amd/powerplay/hwmgr/cz_hwmgr.c

@@ -1494,8 +1494,9 @@ cz_print_current_perforce_level(struct pp_hwmgr *hwmgr, struct seq_file *m)
 	uint32_t vce_index = PHM_GET_FIELD(cgs_read_ind_register(hwmgr->device, CGS_IND_REG__SMC, ixTARGET_AND_CURRENT_PROFILE_INDEX_2),
 					TARGET_AND_CURRENT_PROFILE_INDEX_2, CURR_VCE_INDEX);
 
-	uint32_t sclk, vclk, dclk, ecclk, tmp;
+	uint32_t sclk, vclk, dclk, ecclk, tmp, active_percent;
 	uint16_t vddnb, vddgfx;
+	int result;
 
 	if (sclk_index >= NUM_SCLK_LEVELS) {
 		seq_printf(m, "\n invalid sclk dpm profile %d\n", sclk_index);
@@ -1532,6 +1533,16 @@ cz_print_current_perforce_level(struct pp_hwmgr *hwmgr, struct seq_file *m)
 			seq_printf(m, "\n index: %u vce ecclk: %u MHz\n", vce_index, ecclk/100);
 		}
 	}
+
+	result = smum_send_msg_to_smc(hwmgr->smumgr, PPSMC_MSG_GetAverageGraphicsActivity);
+	if (0 == result) {
+		active_percent = cgs_read_register(hwmgr->device, mmSMU_MP1_SRBM2P_ARG_0);
+		active_percent = active_percent > 100 ? 100 : active_percent;
+	} else {
+		active_percent = 50;
+	}
+
+	seq_printf(m, "\n [GPU load]: %u %%\n\n", active_percent);
 }
 
 static void cz_hw_print_display_cfg(