diff --git a/src/cpu/x86/smi_trigger.c b/src/cpu/x86/smi_trigger.c
index 470ecde..9781642 100644
--- a/src/cpu/x86/smi_trigger.c
+++ b/src/cpu/x86/smi_trigger.c
@@ -38,7 +38,7 @@
 	apmc_log(__func__, cmd);
 
 	/* Now raise the SMI. */
-	outb(cmd, APM_CNT);
+	outb(cmd, pm_acpi_smi_cmd_port());
 
 	printk(BIOS_DEBUG, "APMC done.\n");
 	return 0;
@@ -46,8 +46,8 @@
 
 u8 apm_get_apmc(void)
 {
-	/* Emulate B2 register as the FADT / Linux expects it */
-	u8 cmd = inb(APM_CNT);
+	/* Read command byte from APMC SMI IO port */
+	u8 cmd = inb(pm_acpi_smi_cmd_port());
 
 	apmc_log("SMI#", cmd);
 	return cmd;