diff --git a/sys/dev/drm/amd/amdgpu/si_dpm.c b/sys/dev/drm/amd/amdgpu/si_dpm.c
--- a/sys/dev/drm/amd/amdgpu/si_dpm.c
+++ b/sys/dev/drm/amd/amdgpu/si_dpm.c
@@ -5659,7 +5659,8 @@
 	u32 threshold;
 	u32 sclk_in_sr = 1350; /* ??? */
 
-	if (state->performance_level_count > SISLANDS_MAX_HARDWARE_POWERLEVELS)
+	if (state->performance_level_count == 0 ||
+	    state->performance_level_count > SISLANDS_MAX_HARDWARE_POWERLEVELS)
 		return -EINVAL;
 
 	threshold = state->performance_levels[state->performance_level_count-1].sclk * 100 / 100;
@@ -5735,10 +5736,15 @@
 	int ret;
 	u32 address = si_pi->state_table_start +
 		offsetof(SISLANDS_SMC_STATETABLE, driverState);
-	u32 state_size = sizeof(SISLANDS_SMC_SWSTATE) +
+	u32 state_size;
+	SISLANDS_SMC_SWSTATE *smc_state = &si_pi->smc_statetable.driverState;
+
+	if (new_state->performance_level_count == 0)
+		return -EINVAL;
+
+	state_size = sizeof(SISLANDS_SMC_SWSTATE) +
 		((new_state->performance_level_count - 1) *
 		 sizeof(SISLANDS_SMC_HW_PERFORMANCE_LEVEL));
-	SISLANDS_SMC_SWSTATE *smc_state = &si_pi->smc_statetable.driverState;
 
 	memset(smc_state, 0, state_size);
 
@@ -7872,8 +7878,10 @@
 
 	if (low)
 		return requested_state->performance_levels[0].sclk;
-	else
+	else if (requested_state->performance_level_count > 0)
 		return requested_state->performance_levels[requested_state->performance_level_count - 1].sclk;
+	else
+		return 0;
 }
 
 static u32 si_dpm_get_mclk(void *handle, bool low)
@@ -7884,8 +7892,10 @@
 
 	if (low)
 		return requested_state->performance_levels[0].mclk;
-	else
+	else if (requested_state->performance_level_count > 0)
 		return requested_state->performance_levels[requested_state->performance_level_count - 1].mclk;
+	else
+		return 0;
 }
 
 static void si_dpm_print_power_state(void *handle,