diff --git a/plat/arm/css/sgi/sgi_bl31_setup.c b/plat/arm/css/sgi/sgi_bl31_setup.c
index 27cf183..9adcb7c 100644
--- a/plat/arm/css/sgi/sgi_bl31_setup.c
+++ b/plat/arm/css/sgi/sgi_bl31_setup.c
@@ -74,7 +74,7 @@
 	#endif
 };
 
-scmi_channel_plat_info_t *plat_css_get_scmi_info(int channel_id)
+scmi_channel_plat_info_t *plat_css_get_scmi_info(unsigned int channel_id)
 {
 	if (sgi_plat_info.platform_id == RD_N1E1_EDGE_SID_VER_PART_NUM ||
 		sgi_plat_info.platform_id == RD_V1_SID_VER_PART_NUM ||