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-rw-r--r--drivers/rtc/rtc-cmos.c193
1 files changed, 131 insertions, 62 deletions
diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c
index 94b89a2d9c2e..e9984650ea95 100644
--- a/drivers/rtc/rtc-cmos.c
+++ b/drivers/rtc/rtc-cmos.c
@@ -36,28 +36,9 @@
#include <linux/platform_device.h>
#include <linux/mod_devicetable.h>
-#ifdef CONFIG_HPET_EMULATE_RTC
-#include <asm/hpet.h>
-#endif
-
/* this is for "generic access to PC-style RTC" using CMOS_READ/CMOS_WRITE */
#include <asm-generic/rtc.h>
-#ifndef CONFIG_HPET_EMULATE_RTC
-#define is_hpet_enabled() 0
-#define hpet_set_alarm_time(hrs, min, sec) do { } while (0)
-#define hpet_set_periodic_freq(arg) 0
-#define hpet_mask_rtc_irq_bit(arg) do { } while (0)
-#define hpet_set_rtc_irq_bit(arg) do { } while (0)
-#define hpet_rtc_timer_init() do { } while (0)
-#define hpet_register_irq_handler(h) 0
-#define hpet_unregister_irq_handler(h) do { } while (0)
-static irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id)
-{
- return 0;
-}
-#endif
-
struct cmos_rtc {
struct rtc_device *rtc;
struct device *dev;
@@ -96,6 +77,72 @@ static inline int is_intr(u8 rtc_intr)
/*----------------------------------------------------------------*/
+/* Much modern x86 hardware has HPETs (10+ MHz timers) which, because
+ * many BIOS programmers don't set up "sane mode" IRQ routing, are mostly
+ * used in a broken "legacy replacement" mode. The breakage includes
+ * HPET #1 hijacking the IRQ for this RTC, and being unavailable for
+ * other (better) use.
+ *
+ * When that broken mode is in use, platform glue provides a partial
+ * emulation of hardware RTC IRQ facilities using HPET #1. We don't
+ * want to use HPET for anything except those IRQs though...
+ */
+#ifdef CONFIG_HPET_EMULATE_RTC
+#include <asm/hpet.h>
+#else
+
+static inline int is_hpet_enabled(void)
+{
+ return 0;
+}
+
+static inline int hpet_mask_rtc_irq_bit(unsigned long mask)
+{
+ return 0;
+}
+
+static inline int hpet_set_rtc_irq_bit(unsigned long mask)
+{
+ return 0;
+}
+
+static inline int
+hpet_set_alarm_time(unsigned char hrs, unsigned char min, unsigned char sec)
+{
+ return 0;
+}
+
+static inline int hpet_set_periodic_freq(unsigned long freq)
+{
+ return 0;
+}
+
+static inline int hpet_rtc_dropped_irq(void)
+{
+ return 0;
+}
+
+static inline int hpet_rtc_timer_init(void)
+{
+ return 0;
+}
+
+extern irq_handler_t hpet_rtc_interrupt;
+
+static inline int hpet_register_irq_handler(irq_handler_t handler)
+{
+ return 0;
+}
+
+static inline int hpet_unregister_irq_handler(irq_handler_t handler)
+{
+ return 0;
+}
+
+#endif
+
+/*----------------------------------------------------------------*/
+
static int cmos_read_time(struct device *dev, struct rtc_time *t)
{
/* REVISIT: if the clock has a "century" register, use
@@ -216,13 +263,14 @@ static int cmos_set_alarm(struct device *dev, struct rtc_wkalrm *t)
sec = t->time.tm_sec;
sec = (sec < 60) ? BIN2BCD(sec) : 0xff;
- hpet_set_alarm_time(t->time.tm_hour, t->time.tm_min, t->time.tm_sec);
spin_lock_irq(&rtc_lock);
/* next rtc irq must not be from previous alarm setting */
rtc_control = CMOS_READ(RTC_CONTROL);
rtc_control &= ~RTC_AIE;
CMOS_WRITE(rtc_control, RTC_CONTROL);
+ hpet_mask_rtc_irq_bit(RTC_AIE);
+
rtc_intr = CMOS_READ(RTC_INTR_FLAGS);
rtc_intr &= (rtc_control & RTC_IRQMASK) | RTC_IRQF;
if (is_intr(rtc_intr))
@@ -240,9 +288,16 @@ 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 (t->enabled) {
rtc_control |= RTC_AIE;
CMOS_WRITE(rtc_control, RTC_CONTROL);
+ hpet_set_rtc_irq_bit(RTC_AIE);
+
rtc_intr = CMOS_READ(RTC_INTR_FLAGS);
rtc_intr &= (rtc_control & RTC_IRQMASK) | RTC_IRQF;
if (is_intr(rtc_intr))
@@ -270,8 +325,8 @@ static int cmos_irq_set_freq(struct device *dev, int freq)
f = 16 - f;
spin_lock_irqsave(&rtc_lock, flags);
- if (!hpet_set_periodic_freq(freq))
- CMOS_WRITE(RTC_REF_CLCK_32KHZ | f, RTC_FREQ_SELECT);
+ hpet_set_periodic_freq(freq);
+ CMOS_WRITE(RTC_REF_CLCK_32KHZ | f, RTC_FREQ_SELECT);
spin_unlock_irqrestore(&rtc_lock, flags);
return 0;
@@ -289,11 +344,13 @@ static int cmos_irq_set_state(struct device *dev, int enabled)
spin_lock_irqsave(&rtc_lock, flags);
rtc_control = CMOS_READ(RTC_CONTROL);
- if (enabled)
+ if (enabled) {
rtc_control |= RTC_PIE;
- else
+ hpet_set_rtc_irq_bit(RTC_PIE);
+ } else {
rtc_control &= ~RTC_PIE;
-
+ hpet_mask_rtc_irq_bit(RTC_PIE);
+ }
CMOS_WRITE(rtc_control, RTC_CONTROL);
rtc_intr = CMOS_READ(RTC_INTR_FLAGS);
@@ -319,11 +376,10 @@ cmos_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
case RTC_AIE_ON:
case RTC_UIE_OFF:
case RTC_UIE_ON:
- case RTC_PIE_OFF:
- case RTC_PIE_ON:
if (!is_valid_irq(cmos->irq))
return -EINVAL;
break;
+ /* PIE ON/OFF is handled by cmos_irq_set_state() */
default:
return -ENOIOCTLCMD;
}
@@ -347,17 +403,8 @@ cmos_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
rtc_control |= RTC_UIE;
hpet_set_rtc_irq_bit(RTC_UIE);
break;
- case RTC_PIE_OFF: /* periodic off */
- rtc_control &= ~RTC_PIE;
- hpet_mask_rtc_irq_bit(RTC_PIE);
- break;
- case RTC_PIE_ON: /* periodic on */
- rtc_control |= RTC_PIE;
- hpet_set_rtc_irq_bit(RTC_PIE);
- break;
}
- if (!is_hpet_enabled())
- CMOS_WRITE(rtc_control, RTC_CONTROL);
+ CMOS_WRITE(rtc_control, RTC_CONTROL);
rtc_intr = CMOS_READ(RTC_INTR_FLAGS);
rtc_intr &= (rtc_control & RTC_IRQMASK) | RTC_IRQF;
@@ -505,18 +552,19 @@ static irqreturn_t cmos_interrupt(int irq, void *p)
u8 rtc_control;
spin_lock(&rtc_lock);
- /*
- * In this case it is HPET RTC interrupt handler
- * calling us, with the interrupt information
- * passed as arg1, instead of irq.
+
+ /* When the HPET interrupt handler calls us, the interrupt
+ * status is passed as arg1 instead of the irq number. But
+ * always clear irq status, even when HPET is in the way.
+ *
+ * Note that HPET and RTC are almost certainly out of phase,
+ * giving different IRQ status ...
*/
+ irqstat = CMOS_READ(RTC_INTR_FLAGS);
+ rtc_control = CMOS_READ(RTC_CONTROL);
if (is_hpet_enabled())
irqstat = (unsigned long)irq & 0xF0;
- else {
- irqstat = CMOS_READ(RTC_INTR_FLAGS);
- rtc_control = CMOS_READ(RTC_CONTROL);
- irqstat &= (rtc_control & RTC_IRQMASK) | RTC_IRQF;
- }
+ irqstat &= (rtc_control & RTC_IRQMASK) | RTC_IRQF;
/* All Linux RTC alarms should be treated as if they were oneshot.
* Similar code may be needed in system wakeup paths, in case the
@@ -526,6 +574,8 @@ static irqreturn_t cmos_interrupt(int irq, void *p)
rtc_control = CMOS_READ(RTC_CONTROL);
rtc_control &= ~RTC_AIE;
CMOS_WRITE(rtc_control, RTC_CONTROL);
+ hpet_mask_rtc_irq_bit(RTC_AIE);
+
CMOS_READ(RTC_INTR_FLAGS);
}
spin_unlock(&rtc_lock);
@@ -632,8 +682,8 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq)
* do something about other clock frequencies.
*/
cmos_rtc.rtc->irq_freq = 1024;
- if (!hpet_set_periodic_freq(cmos_rtc.rtc->irq_freq))
- CMOS_WRITE(RTC_REF_CLCK_32KHZ | 0x06, RTC_FREQ_SELECT);
+ hpet_set_periodic_freq(cmos_rtc.rtc->irq_freq);
+ CMOS_WRITE(RTC_REF_CLCK_32KHZ | 0x06, RTC_FREQ_SELECT);
/* disable irqs.
*
@@ -643,6 +693,8 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq)
rtc_control = CMOS_READ(RTC_CONTROL);
rtc_control &= ~(RTC_PIE | RTC_AIE | RTC_UIE);
CMOS_WRITE(rtc_control, RTC_CONTROL);
+ hpet_mask_rtc_irq_bit(RTC_PIE | RTC_AIE | RTC_UIE);
+
CMOS_READ(RTC_INTR_FLAGS);
spin_unlock_irq(&rtc_lock);
@@ -690,7 +742,7 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq)
goto cleanup2;
}
- pr_info("%s: alarms up to one %s%s\n",
+ pr_info("%s: alarms up to one %s%s%s\n",
cmos_rtc.rtc->dev.bus_id,
is_valid_irq(rtc_irq)
? (cmos_rtc.mon_alrm
@@ -698,8 +750,8 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq)
: (cmos_rtc.day_alrm
? "month" : "day"))
: "no",
- cmos_rtc.century ? ", y3k" : ""
- );
+ cmos_rtc.century ? ", y3k" : "",
+ is_hpet_enabled() ? ", hpet irqs" : "");
return 0;
@@ -720,8 +772,10 @@ static void cmos_do_shutdown(void)
spin_lock_irq(&rtc_lock);
rtc_control = CMOS_READ(RTC_CONTROL);
- rtc_control &= ~(RTC_PIE|RTC_AIE|RTC_UIE);
+ rtc_control &= ~RTC_IRQMASK;
CMOS_WRITE(rtc_control, RTC_CONTROL);
+ hpet_mask_rtc_irq_bit(RTC_IRQMASK);
+
CMOS_READ(RTC_INTR_FLAGS);
spin_unlock_irq(&rtc_lock);
}
@@ -764,12 +818,16 @@ static int cmos_suspend(struct device *dev, pm_message_t mesg)
cmos->suspend_ctrl = tmp = CMOS_READ(RTC_CONTROL);
if (tmp & (RTC_PIE|RTC_AIE|RTC_UIE)) {
unsigned char irqstat;
+ unsigned char mask;
if (do_wake)
- tmp &= ~(RTC_PIE|RTC_UIE);
+ mask = RTC_IRQMASK & ~RTC_AIE;
else
- tmp &= ~(RTC_PIE|RTC_AIE|RTC_UIE);
+ mask = RTC_IRQMASK;
+ tmp &= ~mask;
CMOS_WRITE(tmp, RTC_CONTROL);
+ hpet_mask_rtc_irq_bit(mask);
+
irqstat = CMOS_READ(RTC_INTR_FLAGS);
irqstat &= (tmp & RTC_IRQMASK) | RTC_IRQF;
if (is_intr(irqstat))
@@ -799,7 +857,8 @@ static int cmos_resume(struct device *dev)
unsigned char tmp = cmos->suspend_ctrl;
/* re-enable any irqs previously active */
- if (tmp & (RTC_PIE|RTC_AIE|RTC_UIE)) {
+ if (tmp & RTC_IRQMASK) {
+ unsigned char mask;
if (cmos->enabled_wake) {
if (cmos->wake_off)
@@ -810,18 +869,28 @@ static int cmos_resume(struct device *dev)
}
spin_lock_irq(&rtc_lock);
- CMOS_WRITE(tmp, RTC_CONTROL);
- tmp = CMOS_READ(RTC_INTR_FLAGS);
- tmp &= (cmos->suspend_ctrl & RTC_IRQMASK) | RTC_IRQF;
- if (is_intr(tmp))
- rtc_update_irq(cmos->rtc, 1, tmp);
+ do {
+ CMOS_WRITE(tmp, RTC_CONTROL);
+ hpet_set_rtc_irq_bit(tmp & RTC_IRQMASK);
+
+ mask = CMOS_READ(RTC_INTR_FLAGS);
+ mask &= (tmp & RTC_IRQMASK) | RTC_IRQF;
+ if (!is_intr(mask))
+ break;
+
+ /* force one-shot behavior if HPET blocked
+ * the wake alarm's irq
+ */
+ rtc_update_irq(cmos->rtc, 1, mask);
+ tmp &= ~RTC_AIE;
+ hpet_mask_rtc_irq_bit(RTC_AIE);
+ } while (mask & RTC_AIE);
spin_unlock_irq(&rtc_lock);
}
pr_debug("%s: resume, ctrl %02x\n",
cmos_rtc.rtc->dev.bus_id,
- cmos->suspend_ctrl);
-
+ tmp);
return 0;
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-11 09:06:05 +0100