[PATCH 2/2] MIPS: SGI-IP30: shut down cleanly on a power button press

From: Imre Kaloz

Date: Tue Oct 13 2026 - 08:42:14 EST


The power button raises a kickstart interrupt on the DS1687, and
rtc-ds1685 cuts power at once unless the platform supplies a
prepare_poweroff hook. Supply one that starts an orderly power-off,
cutting power directly on a second press or after 120 seconds.

Signed-off-by: Imre Kaloz <kaloz@xxxxxxxxxx>
---
arch/mips/include/asm/sgi/heart.h | 2 ++
arch/mips/sgi-ip30/ip30-power.c | 26 ++++++++++++++++++++++++++
drivers/mfd/ioc3.c | 6 ++++++
3 files changed, 34 insertions(+)

diff --git a/arch/mips/include/asm/sgi/heart.h b/arch/mips/include/asm/sgi/heart.h
index c224c2e3575a..736cabb7fdbb 100644
--- a/arch/mips/include/asm/sgi/heart.h
+++ b/arch/mips/include/asm/sgi/heart.h
@@ -317,6 +317,8 @@ struct ip30_heart_regs { /* 0x0ff00000 */

extern struct ip30_heart_regs __iomem *heart_regs;

+void ip30_prepare_poweroff(void);
+
#define heart_read ____raw_readq
#define heart_write ____raw_writeq

diff --git a/arch/mips/sgi-ip30/ip30-power.c b/arch/mips/sgi-ip30/ip30-power.c
index 2b862b27e114..1200fef108b1 100644
--- a/arch/mips/sgi-ip30/ip30-power.c
+++ b/arch/mips/sgi-ip30/ip30-power.c
@@ -17,6 +17,8 @@
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/pm.h>
+#include <linux/reboot.h>
+#include <linux/workqueue.h>

#include <asm/reboot.h>
#include <asm/sgi/heart.h>
@@ -52,6 +54,30 @@ static void ip30_machine_power_off(void)
ds1685_rtc_poweroff(to_platform_device(dev));
}

+#define IP30_POWERDOWN_TIMEOUT 120 /* seconds */
+
+static bool ip30_shutting_down;
+
+static void ip30_power_timeout(struct work_struct *work)
+{
+ ip30_machine_power_off();
+}
+
+static DECLARE_DELAYED_WORK(ip30_power_work, ip30_power_timeout);
+
+/* Called by the RTC driver when the power button is pressed. */
+void ip30_prepare_poweroff(void)
+{
+ /* A second press powers off at once. */
+ if (ip30_shutting_down)
+ ip30_machine_power_off();
+
+ /* Shut down through userspace, powering off anyway if it stalls. */
+ ip30_shutting_down = true;
+ orderly_poweroff(true);
+ schedule_delayed_work(&ip30_power_work, IP30_POWERDOWN_TIMEOUT * HZ);
+}
+
static int __init ip30_reboot_setup(void)
{
_machine_restart = ip30_machine_restart;
diff --git a/drivers/mfd/ioc3.c b/drivers/mfd/ioc3.c
index 5f8ac364b610..8f603651cc8e 100644
--- a/drivers/mfd/ioc3.c
+++ b/drivers/mfd/ioc3.c
@@ -24,6 +24,9 @@

#include <asm/pci/bridge.h>
#include <asm/sn/ioc3.h>
+#ifdef CONFIG_SGI_IP30
+#include <asm/sgi/heart.h>
+#endif

#define IOC3_IRQ_SERIAL_A 6
#define IOC3_IRQ_SERIAL_B 15
@@ -321,6 +324,9 @@ static struct ds1685_rtc_platform_data ip30_rtc_platform_data = {
.no_irq = false,
.uie_unsupported = true,
.access_type = ds1685_reg_indirect,
+#ifdef CONFIG_SGI_IP30
+ .plat_prepare_poweroff = ip30_prepare_poweroff,
+#endif
};

static const struct resource ioc3_rtc_ds1685_resources[] = {
--
2.47.3