Merge branch 'for-4.19/wiimote' into for-linus
[linux-2.6-microblaze.git] / drivers / rtc / rtc-cmos.c
index 1b3738a..cd3a241 100644 (file)
 #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, &current_alarm);
        t_current_expires = rtc_tm_to_time64(&current_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;