diff --git a/src/soc/amd/stoneyridge/include/soc/southbridge.h b/src/soc/amd/stoneyridge/include/soc/southbridge.h
index 9f353fbdfd..aa93e47ed2 100644
--- a/src/soc/amd/stoneyridge/include/soc/southbridge.h
+++ b/src/soc/amd/stoneyridge/include/soc/southbridge.h
@@ -189,7 +189,7 @@ void sb_tpm_decode_spi(void);
 void lpc_wideio_512_window(uint16_t base);
 void lpc_wideio_16_window(uint16_t base);
 u8 pm_read8(u8 reg);
-u16 pm_read16(u16 reg);
+u16 pm_read16(u8 reg);
 void pm_write8(u8 reg, u8 value);
 void pm_write16(u8 reg, u16 value);
 int s3_load_nvram_early(int size, u32 *old_dword, int nvram_pos);
diff --git a/src/soc/amd/stoneyridge/southbridge.c b/src/soc/amd/stoneyridge/southbridge.c
index 92a1defb94..ebda770be2 100644
--- a/src/soc/amd/stoneyridge/southbridge.c
+++ b/src/soc/amd/stoneyridge/southbridge.c
@@ -53,7 +53,7 @@ void pm_write16(u8 reg, u16 value)
 	write16((void *)(PM_MMIO_BASE + reg), value);
 }
 
-u16 pm_read16(u16 reg)
+u16 pm_read16(u8 reg)
 {
 	return read16((void *)(PM_MMIO_BASE + reg));
 }