diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c
index 1b3738a11702465f4728a08d14d07e4902970b2e..cd3a2411bc2f57b9a4758e2480acef0ac6fe82fc 100644
--- a/drivers/rtc/rtc-cmos.c
+++ b/drivers/rtc/rtc-cmos.c
@@ -43,11 +43,24 @@
#include <linux/of_platform.h>
#ifdef CONFIG_X86
#include <asm/i8259.h>
+#include <asm/processor.h>
+#include <linux/dmi.h>
#endif
/* this is for "generic access to PC-style RTC" using CMOS_READ/CMOS_WRITE */
#include <linux/mc146818rtc.h>
+/*
+ * Use ACPI SCI to replace HPET interrupt for RTC Alarm event
+ *
+ * If cleared, ACPI SCI is only used to wake up the system from suspend
+ *
+ * If set, ACPI SCI is used to handle UIE/AIE and system wakeup
+ */
+
+static bool use_acpi_alarm;
+module_param(use_acpi_alarm, bool, 0444);
+
struct cmos_rtc {
struct rtc_device *rtc;
struct device *dev;
@@ -153,6 +166,12 @@ static inline int hpet_unregister_irq_handler(irq_handler_t handler)
#endif
+/* Don't use HPET for RTC Alarm event if ACPI Fixed event is used */
+static int use_hpet_alarm(void)
+{
+ return is_hpet_enabled() && !use_acpi_alarm;
+}
+
/*----------------------------------------------------------------*/
#ifdef RTC_PORT
@@ -298,7 +317,7 @@ static void cmos_checkintr(struct cmos_rtc *cmos, unsigned char rtc_control)
*/
rtc_intr = CMOS_READ(RTC_INTR_FLAGS);
- if (is_hpet_enabled())
+ if (use_hpet_alarm())
return;
rtc_intr &= (rtc_control & RTC_IRQMASK) | RTC_IRQF;
@@ -318,7 +337,13 @@ static void cmos_irq_enable(struct cmos_rtc *cmos, unsigned char mask)
rtc_control |= mask;
CMOS_WRITE(rtc_control, RTC_CONTROL);
- hpet_set_rtc_irq_bit(mask);
+ if (use_hpet_alarm())
+ hpet_set_rtc_irq_bit(mask);
+
+ if ((mask & RTC_AIE) && use_acpi_alarm) {
+ if (cmos->wake_on)
+ cmos->wake_on(cmos->dev);
+ }
cmos_checkintr(cmos, rtc_control);
}
@@ -330,7 +355,13 @@ static void cmos_irq_disable(struct cmos_rtc *cmos, unsigned char mask)
rtc_control = CMOS_READ(RTC_CONTROL);
rtc_control &= ~mask;
CMOS_WRITE(rtc_control, RTC_CONTROL);
- hpet_mask_rtc_irq_bit(mask);
+ if (use_hpet_alarm())
+ hpet_mask_rtc_irq_bit(mask);
+
+ if ((mask & RTC_AIE) && use_acpi_alarm) {
+ if (cmos->wake_off)
+ cmos->wake_off(cmos->dev);
+ }
cmos_checkintr(cmos, rtc_control);
}
@@ -448,10 +479,14 @@ static int cmos_set_alarm(struct device *dev, struct rtc_wkalrm *t)
CMOS_WRITE(mon, cmos->mon_alrm);
}
- /* FIXME the HPET alarm glue currently ignores day_alrm
- * and mon_alrm ...
- */
- hpet_set_alarm_time(t->time.tm_hour, t->time.tm_min, t->time.tm_sec);
+ if (use_hpet_alarm()) {
+ /*
+ * FIXME the HPET alarm glue currently ignores day_alrm
+ * and mon_alrm ...
+ */
+ hpet_set_alarm_time(t->time.tm_hour, t->time.tm_min,
+ t->time.tm_sec);
+ }
if (t->enabled)
cmos_irq_enable(cmos, RTC_AIE);
@@ -508,7 +543,7 @@ static int cmos_procfs(struct device *dev, struct seq_file *seq)
"batt_status\t: %s\n",
(rtc_control & RTC_PIE) ? "yes" : "no",
(rtc_control & RTC_UIE) ? "yes" : "no",
- is_hpet_enabled() ? "yes" : "no",
+ use_hpet_alarm() ? "yes" : "no",
// (rtc_control & RTC_SQWE) ? "yes" : "no",
(rtc_control & RTC_DM_BINARY) ? "no" : "yes",
(rtc_control & RTC_DST_EN) ? "yes" : "no",
@@ -614,7 +649,7 @@ static irqreturn_t cmos_interrupt(int irq, void *p)
*/
irqstat = CMOS_READ(RTC_INTR_FLAGS);
rtc_control = CMOS_READ(RTC_CONTROL);
- if (is_hpet_enabled())
+ if (use_hpet_alarm())
irqstat = (unsigned long)irq & 0xF0;
/* If we were suspended, RTC_CONTROL may not be accurate since the
@@ -633,7 +668,8 @@ static irqreturn_t cmos_interrupt(int irq, void *p)
cmos_rtc.suspend_ctrl &= ~RTC_AIE;
rtc_control &= ~RTC_AIE;
CMOS_WRITE(rtc_control, RTC_CONTROL);
- hpet_mask_rtc_irq_bit(RTC_AIE);
+ if (use_hpet_alarm())
+ hpet_mask_rtc_irq_bit(RTC_AIE);
CMOS_READ(RTC_INTR_FLAGS);
}
spin_unlock(&rtc_lock);
@@ -762,7 +798,8 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq)
* need to do something about other clock frequencies.
*/
cmos_rtc.rtc->irq_freq = 1024;
- hpet_set_periodic_freq(cmos_rtc.rtc->irq_freq);
+ if (use_hpet_alarm())
+ hpet_set_periodic_freq(cmos_rtc.rtc->irq_freq);
CMOS_WRITE(RTC_REF_CLCK_32KHZ | 0x06, RTC_FREQ_SELECT);
}
@@ -780,12 +817,13 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq)
goto cleanup1;
}
- hpet_rtc_timer_init();
+ if (use_hpet_alarm())
+ hpet_rtc_timer_init();
if (is_valid_irq(rtc_irq)) {
irq_handler_t rtc_cmos_int_handler;
- if (is_hpet_enabled()) {
+ if (use_hpet_alarm()) {
rtc_cmos_int_handler = hpet_rtc_interrupt;
retval = hpet_register_irq_handler(cmos_interrupt);
if (retval) {
@@ -824,7 +862,7 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq)
"alarms up to one day",
cmos_rtc.century ? ", y3k" : "",
nvmem_cfg.size,
- is_hpet_enabled() ? ", hpet irqs" : "");
+ use_hpet_alarm() ? ", hpet irqs" : "");
return 0;
@@ -858,7 +896,8 @@ static void cmos_do_remove(struct device *dev)
if (is_valid_irq(cmos->irq)) {
free_irq(cmos->irq, cmos->rtc);
- hpet_unregister_irq_handler(cmos_interrupt);
+ if (use_hpet_alarm())
+ hpet_unregister_irq_handler(cmos_interrupt);
}
cmos->rtc = NULL;
@@ -935,13 +974,13 @@ static int cmos_suspend(struct device *dev)
mask = RTC_IRQMASK;
tmp &= ~mask;
CMOS_WRITE(tmp, RTC_CONTROL);
- hpet_mask_rtc_irq_bit(mask);
-
+ if (use_hpet_alarm())
+ hpet_mask_rtc_irq_bit(mask);
cmos_checkintr(cmos, tmp);
}
spin_unlock_irq(&rtc_lock);
- if (tmp & RTC_AIE) {
+ if ((tmp & RTC_AIE) && !use_acpi_alarm) {
cmos->enabled_wake = 1;
if (cmos->wake_on)
cmos->wake_on(dev);
@@ -976,8 +1015,26 @@ static void cmos_check_wkalrm(struct device *dev)
{
struct cmos_rtc *cmos = dev_get_drvdata(dev);
struct rtc_wkalrm current_alarm;
+ time64_t t_now;
time64_t t_current_expires;
time64_t t_saved_expires;
+ struct rtc_time now;
+
+ /* Check if we have RTC Alarm armed */
+ if (!(cmos->suspend_ctrl & RTC_AIE))
+ return;
+
+ cmos_read_time(dev, &now);
+ t_now = rtc_tm_to_time64(&now);
+
+ /*
+ * ACPI RTC wake event is cleared after resume from STR,
+ * ACK the rtc irq here
+ */
+ if (t_now >= cmos->alarm_expires && use_acpi_alarm) {
+ cmos_interrupt(0, (void *)cmos->rtc);
+ return;
+ }
cmos_read_alarm(dev, ¤t_alarm);
t_current_expires = rtc_tm_to_time64(¤t_alarm.time);
@@ -996,7 +1053,7 @@ static int __maybe_unused cmos_resume(struct device *dev)
struct cmos_rtc *cmos = dev_get_drvdata(dev);
unsigned char tmp;
- if (cmos->enabled_wake) {
+ if (cmos->enabled_wake && !use_acpi_alarm) {
if (cmos->wake_off)
cmos->wake_off(dev);
else
@@ -1014,16 +1071,17 @@ static int __maybe_unused cmos_resume(struct device *dev)
if (tmp & RTC_IRQMASK) {
unsigned char mask;
- if (device_may_wakeup(dev))
+ if (device_may_wakeup(dev) && use_hpet_alarm())
hpet_rtc_timer_init();
do {
CMOS_WRITE(tmp, RTC_CONTROL);
- hpet_set_rtc_irq_bit(tmp & RTC_IRQMASK);
+ if (use_hpet_alarm())
+ hpet_set_rtc_irq_bit(tmp & RTC_IRQMASK);
mask = CMOS_READ(RTC_INTR_FLAGS);
mask &= (tmp & RTC_IRQMASK) | RTC_IRQF;
- if (!is_hpet_enabled() || !is_intr(mask))
+ if (!use_hpet_alarm() || !is_intr(mask))
break;
/* force one-shot behavior if HPET blocked
@@ -1068,16 +1126,27 @@ static u32 rtc_handler(void *context)
unsigned char rtc_intr;
unsigned long flags;
- spin_lock_irqsave(&rtc_lock, flags);
- if (cmos_rtc.suspend_ctrl)
- rtc_control = CMOS_READ(RTC_CONTROL);
- if (rtc_control & RTC_AIE) {
- cmos_rtc.suspend_ctrl &= ~RTC_AIE;
- CMOS_WRITE(rtc_control, RTC_CONTROL);
- rtc_intr = CMOS_READ(RTC_INTR_FLAGS);
- rtc_update_irq(cmos->rtc, 1, rtc_intr);
+
+ /*
+ * Always update rtc irq when ACPI is used as RTC Alarm.
+ * Or else, ACPI SCI is enabled during suspend/resume only,
+ * update rtc irq in that case.
+ */
+ if (use_acpi_alarm)
+ cmos_interrupt(0, (void *)cmos->rtc);
+ else {
+ /* Fix me: can we use cmos_interrupt() here as well? */
+ spin_lock_irqsave(&rtc_lock, flags);
+ if (cmos_rtc.suspend_ctrl)
+ rtc_control = CMOS_READ(RTC_CONTROL);
+ if (rtc_control & RTC_AIE) {
+ cmos_rtc.suspend_ctrl &= ~RTC_AIE;
+ CMOS_WRITE(rtc_control, RTC_CONTROL);
+ rtc_intr = CMOS_READ(RTC_INTR_FLAGS);
+ rtc_update_irq(cmos->rtc, 1, rtc_intr);
+ }
+ spin_unlock_irqrestore(&rtc_lock, flags);
}
- spin_unlock_irqrestore(&rtc_lock, flags);
pm_wakeup_hard_event(dev);
acpi_clear_event(ACPI_EVENT_RTC);
@@ -1107,6 +1176,28 @@ static void rtc_wake_off(struct device *dev)
acpi_disable_event(ACPI_EVENT_RTC, 0);
}
+#ifdef CONFIG_X86
+/* Enable use_acpi_alarm mode for Intel platforms no earlier than 2015 */
+static void use_acpi_alarm_quirks(void)
+{
+ int year;
+
+ if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
+ return;
+
+ if (!(acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0))
+ return;
+
+ if (!is_hpet_enabled())
+ return;
+
+ if (dmi_get_date(DMI_BIOS_DATE, &year, NULL, NULL) && year >= 2015)
+ use_acpi_alarm = true;
+}
+#else
+static inline void use_acpi_alarm_quirks(void) { }
+#endif
+
/* Every ACPI platform has a mc146818 compatible "cmos rtc". Here we find
* its device node and pass extra config data. This helps its driver use
* capabilities that the now-obsolete mc146818 didn't have, and informs it
@@ -1119,6 +1210,8 @@ static void cmos_wake_setup(struct device *dev)
if (acpi_disabled)
return;
+ use_acpi_alarm_quirks();
+
rtc_wake_setup(dev);
acpi_rtc_info.wake_on = rtc_wake_on;
acpi_rtc_info.wake_off = rtc_wake_off;