diff --git a/sys/amd64/acpica/acpi_wakeup.c b/sys/amd64/acpica/acpi_wakeup.c
--- a/sys/amd64/acpica/acpi_wakeup.c
+++ b/sys/amd64/acpica/acpi_wakeup.c
@@ -218,7 +218,8 @@
 		WAKECODE_FIXUP(wakeup_gdt + 2, uint64_t, pcb->pcb_gdt.rd_base);
 
 		/* Call ACPICA to enter the desired sleep state */
-		if (state == ACPI_STATE_S4 && sc->acpi_s4bios)
+		if (state == ACPI_STATE_S4 &&
+		    acpi_S4_should_firmware_initiate(sc))
 			status = AcpiEnterSleepStateS4bios();
 		else
 			status = AcpiEnterSleepState(state);
diff --git a/sys/dev/acpica/acpi.c b/sys/dev/acpica/acpi.c
--- a/sys/dev/acpica/acpi.c
+++ b/sys/dev/acpica/acpi.c
@@ -631,7 +631,11 @@
 	"sleep delay in seconds");
     SYSCTL_ADD_BOOL(&sc->acpi_sysctl_ctx, SYSCTL_CHILDREN(sc->acpi_sysctl_tree),
 	OID_AUTO, "s4bios", CTLFLAG_RW, &sc->acpi_s4bios, 0,
-	"When hibernating, have the firmware save the machine state (S4BIOS).");
+	"When hibernating, have the firmware save the machine state (S4BIOS), "
+	"if supported.");
+    SYSCTL_ADD_BOOL(&sc->acpi_sysctl_ctx, SYSCTL_CHILDREN(sc->acpi_sysctl_tree),
+	OID_AUTO, "s4bios_supported", CTLFLAG_RD, &sc->acpi_s4bios_supported, 0,
+	"Whether firmware supports saving the machine state (S4BIOS).");
     SYSCTL_ADD_INT(&sc->acpi_sysctl_ctx, SYSCTL_CHILDREN(sc->acpi_sysctl_tree),
 	OID_AUTO, "verbose", CTLFLAG_RW, &sc->acpi_verbose, 0, "verbose mode");
     SYSCTL_ADD_INT(&sc->acpi_sysctl_ctx, SYSCTL_CHILDREN(sc->acpi_sysctl_tree),
@@ -673,7 +677,7 @@
 
     /* Only enable S4BIOS by default if the FACS says it is available. */
     if (AcpiGbl_FACS != NULL && AcpiGbl_FACS->Flags & ACPI_FACS_S4_BIOS_PRESENT)
-	sc->acpi_s4bios = true;
+	sc->acpi_s4bios = sc->acpi_s4bios_supported = true;
 
     /*
      * Probe all supported ACPI sleep states.  Awake (S0) is always supported.
diff --git a/sys/dev/acpica/acpivar.h b/sys/dev/acpica/acpivar.h
--- a/sys/dev/acpica/acpivar.h
+++ b/sys/dev/acpica/acpivar.h
@@ -65,6 +65,7 @@
 
     int			acpi_standby_sx;
     bool		acpi_s4bios;
+    bool		acpi_s4bios_supported;
 
     int			acpi_sleep_delay;
     int			acpi_do_disable;
@@ -527,6 +528,12 @@
     return (strs[state]);
 }
 
+static __inline bool
+acpi_S4_should_firmware_initiate(struct acpi_softc *sc)
+{
+    return (sc->acpi_s4bios_supported && sc->acpi_s4bios);
+}
+
 char		*acpi_name(ACPI_HANDLE handle);
 int		acpi_avoid(ACPI_HANDLE handle);
 int		acpi_disabled(char *subsys);
diff --git a/sys/i386/acpica/acpi_wakeup.c b/sys/i386/acpica/acpi_wakeup.c
--- a/sys/i386/acpica/acpi_wakeup.c
+++ b/sys/i386/acpica/acpi_wakeup.c
@@ -240,7 +240,8 @@
 		pmap_remap_lowptdi(true);
 
 		/* Call ACPICA to enter the desired sleep state */
-		if (state == ACPI_STATE_S4 && sc->acpi_s4bios)
+		if (state == ACPI_STATE_S4 &&
+		    acpi_S4_should_firmware_initiate(sc))
 			status = AcpiEnterSleepStateS4bios();
 		else
 			status = AcpiEnterSleepState(state);