diff --git a/drivers/gpu/drm/i915/display/intel_cx0_phy.c b/drivers/gpu/drm/i915/display/intel_cx0_phy.c
index 2ab93d02fdf1..f190762e4871 100644
--- a/drivers/gpu/drm/i915/display/intel_cx0_phy.c
+++ b/drivers/gpu/drm/i915/display/intel_cx0_phy.c
@@ -2059,6 +2059,9 @@ static void intel_cx0pll_update_ssc(struct intel_encoder *encoder,
 	}
 }
 
+#define C10_PLL_SSC_REG_START_IDX	4
+#define C10_PLL_SSC_REG_COUNT		5
+
 static void intel_c10pll_update_pll(struct intel_encoder *encoder,
 				    struct intel_cx0pll_state *pll_state)
 {
@@ -2068,8 +2071,11 @@ static void intel_c10pll_update_pll(struct intel_encoder *encoder,
 	if (pll_state->ssc_enabled)
 		return;
 
-	drm_WARN_ON(display->drm, ARRAY_SIZE(pll_state->c10.pll) < 9);
-	for (i = 4; i < 9; i++)
+	drm_WARN_ON(display->drm, ARRAY_SIZE(pll_state->c10.pll) <
+				  C10_PLL_SSC_REG_START_IDX + C10_PLL_SSC_REG_COUNT);
+	for (i = C10_PLL_SSC_REG_START_IDX;
+	     i < C10_PLL_SSC_REG_START_IDX + C10_PLL_SSC_REG_COUNT;
+	     i++)
 		pll_state->c10.pll[i] = 0;
 }