diff --git a/hw/hppa/machine.c b/hw/hppa/machine.c
index 54ca2fd91a..9e611620cc 100644
--- a/hw/hppa/machine.c
+++ b/hw/hppa/machine.c
@@ -36,8 +36,8 @@
 
 #define MIN_SEABIOS_HPPA_VERSION 12 /* require at least this fw version */
 
-/* Power button address at &PAGE0->pad[4] */
-#define HPA_POWER_BUTTON (0x40 + 4 * sizeof(uint32_t))
+#define HPA_POWER_BUTTON        (FIRMWARE_END - 0x10)
+static hwaddr soft_power_reg;
 
 #define enable_lasi_lan()       0
 
@@ -45,7 +45,6 @@ static DeviceState *lasi_dev;
 
 static void hppa_powerdown_req(Notifier *n, void *opaque)
 {
-    hwaddr soft_power_reg = HPA_POWER_BUTTON;
     uint32_t val;
 
     val = ldl_be_phys(&address_space_memory, soft_power_reg);
@@ -221,7 +220,7 @@ static FWCfgState *create_fw_cfg(MachineState *ms, PCIBus *pci_bus,
     fw_cfg_add_file(fw_cfg, "/etc/hppa/machine",
                     g_memdup(mc->name, len), len);
 
-    val = cpu_to_le64(HPA_POWER_BUTTON);
+    val = cpu_to_le64(soft_power_reg);
     fw_cfg_add_file(fw_cfg, "/etc/hppa/power-button-addr",
                     g_memdup(&val, sizeof(val)), sizeof(val));
 
@@ -295,6 +294,8 @@ static TranslateFn *machine_HP_common_init_cpus(MachineState *machine)
         ram_max = 0xf0000000;      /* 3.75 GB (32-bit CPU) */
     }
 
+    soft_power_reg = translate(NULL, HPA_POWER_BUTTON);
+
     for (unsigned int i = 0; i < smp_cpus; i++) {
         g_autofree char *name = g_strdup_printf("cpu%u-io-eir", i);