hrtimer: Add hrtimer support for CLOCK_TAI

Add hrtimer support for CLOCK_TAI, as well as posix timer interfaces.

Signed-off-by: John Stultz <john.stultz@linaro.org>

5 files changed, 44 insertions, 3 deletions

diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
index cc07d2777bbe..d19a5c2d2270 100644
--- a/include/linux/hrtimer.h
+++ b/include/linux/hrtimer.h
@@ -157,6 +157,7 @@ enum  hrtimer_base_type {
         HRTIMER_BASE_MONOTONIC,
         HRTIMER_BASE_REALTIME,
         HRTIMER_BASE_BOOTTIME,
+        HRTIMER_BASE_TAI,
         HRTIMER_MAX_CLOCK_BASES,
 };
 
@@ -327,7 +328,9 @@ extern ktime_t ktime_get(void);
 extern ktime_t ktime_get_real(void);
 extern ktime_t ktime_get_boottime(void);
 extern ktime_t ktime_get_monotonic_offset(void);
-extern ktime_t ktime_get_update_offsets(ktime_t *offs_real, ktime_t *offs_boot);
+extern ktime_t ktime_get_clocktai(void);
+extern ktime_t ktime_get_update_offsets(ktime_t *offs_real, ktime_t *offs_boot,
+                                         ktime_t *offs_tai);
 
 DECLARE_PER_CPU(struct tick_device, tick_cpu_device);
 
diff --git a/include/linux/timekeeper_internal.h b/include/linux/timekeeper_internal.h
index ff94f436f8b7..26700d870506 100644
--- a/include/linux/timekeeper_internal.h
+++ b/include/linux/timekeeper_internal.h
@@ -64,6 +64,8 @@ struct timekeeper {
         struct timespec         raw_time;
         /* The current UTC to TAI offset in seconds */
         s32                     tai_offset;
+        /* Offset clock monotonic -> clock tai */
+        ktime_t                 offs_tai;
 
         /* Seqlock for all timekeeper values */
         seqlock_t               lock;
diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index cc47812d3feb..258720741d3e 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -83,6 +83,12 @@ DEFINE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases) =
                         .get_time = &ktime_get_boottime,
                         .resolution = KTIME_LOW_RES,
                 },
+                {
+                        .index = HRTIMER_BASE_TAI,
+                        .clockid = CLOCK_TAI,
+                        .get_time = &ktime_get_clocktai,
+                        .resolution = KTIME_LOW_RES,
+                },
         }
 };
 
@@ -90,6 +96,7 @@ static const int hrtimer_clock_to_base_table[MAX_CLOCKS] = {
         [CLOCK_REALTIME]        = HRTIMER_BASE_REALTIME,
         [CLOCK_MONOTONIC]       = HRTIMER_BASE_MONOTONIC,
         [CLOCK_BOOTTIME]        = HRTIMER_BASE_BOOTTIME,
+        [CLOCK_TAI]             = HRTIMER_BASE_TAI,
 };
 
 static inline int hrtimer_clockid_to_base(clockid_t clock_id)
@@ -106,8 +113,10 @@ static void hrtimer_get_softirq_time(struct hrtimer_cpu_base *base)
 {
         ktime_t xtim, mono, boot;
         struct timespec xts, tom, slp;
+        s32 tai_offset;
 
         get_xtime_and_monotonic_and_sleep_offset(&xts, &tom, &slp);
+        tai_offset = timekeeping_get_tai_offset();
 
         xtim = timespec_to_ktime(xts);
         mono = ktime_add(xtim, timespec_to_ktime(tom));
@@ -115,6 +124,8 @@ static void hrtimer_get_softirq_time(struct hrtimer_cpu_base *base)
         base->clock_base[HRTIMER_BASE_REALTIME].softirq_time = xtim;
         base->clock_base[HRTIMER_BASE_MONOTONIC].softirq_time = mono;
         base->clock_base[HRTIMER_BASE_BOOTTIME].softirq_time = boot;
+        base->clock_base[HRTIMER_BASE_TAI].softirq_time =
+                                ktime_add(xtim, ktime_set(tai_offset, 0));
 }
 
 /*
@@ -651,8 +662,9 @@ static inline ktime_t hrtimer_update_base(struct hrtimer_cpu_base *base)
 {
         ktime_t *offs_real = &base->clock_base[HRTIMER_BASE_REALTIME].offset;
         ktime_t *offs_boot = &base->clock_base[HRTIMER_BASE_BOOTTIME].offset;
+        ktime_t *offs_tai = &base->clock_base[HRTIMER_BASE_TAI].offset;
 
-        return ktime_get_update_offsets(offs_real, offs_boot);
+        return ktime_get_update_offsets(offs_real, offs_boot, offs_tai);
 }
 
 /*
diff --git a/kernel/posix-timers.c b/kernel/posix-timers.c
index fbfc5f1b7710..2a2e173d0a7a 100644
--- a/kernel/posix-timers.c
+++ b/kernel/posix-timers.c
@@ -269,6 +269,12 @@ static __init int init_posix_timers(void)
         struct k_clock clock_tai = {
                 .clock_getres   = hrtimer_get_res,
                 .clock_get      = posix_get_tai,
+                .nsleep         = common_nsleep,
+                .nsleep_restart = hrtimer_nanosleep_restart,
+                .timer_create   = common_timer_create,
+                .timer_set      = common_timer_set,
+                .timer_get      = common_timer_get,
+                .timer_del      = common_timer_del,
         };
         struct k_clock clock_boottime = {
                 .clock_getres   = hrtimer_get_res,
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 8a842756572d..8061ae0be7bd 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -67,6 +67,7 @@ static void tk_set_wall_to_mono(struct timekeeper *tk, struct timespec wtm)
         tk->wall_to_monotonic = wtm;
         set_normalized_timespec(&tmp, -wtm.tv_sec, -wtm.tv_nsec);
         tk->offs_real = timespec_to_ktime(tmp);
+        tk->offs_tai = ktime_sub(tk->offs_real, ktime_set(tk->tai_offset, 0));
 }
 
 static void tk_set_sleep_time(struct timekeeper *tk, struct timespec t)
@@ -409,6 +410,20 @@ void timekeeping_clocktai(struct timespec *ts)
 EXPORT_SYMBOL(timekeeping_clocktai);
 
 
+/**
+ * ktime_get_clocktai - Returns the TAI time of day in a ktime
+ *
+ * Returns the time of day in a ktime.
+ */
+ktime_t ktime_get_clocktai(void)
+{
+        struct timespec ts;
+
+        timekeeping_clocktai(&ts);
+        return timespec_to_ktime(ts);
+}
+EXPORT_SYMBOL(ktime_get_clocktai);
+
 #ifdef CONFIG_NTP_PPS
 
 /**
@@ -569,6 +584,7 @@ s32 timekeeping_get_tai_offset(void)
 void __timekeeping_set_tai_offset(struct timekeeper *tk, s32 tai_offset)
 {
         tk->tai_offset = tai_offset;
+        tk->offs_tai = ktime_sub(tk->offs_real, ktime_set(tai_offset, 0));
 }
 
 /**
@@ -1539,7 +1555,8 @@ void get_xtime_and_monotonic_and_sleep_offset(struct timespec *xtim,
  * Returns current monotonic time and updates the offsets
  * Called from hrtimer_interupt() or retrigger_next_event()
  */
-ktime_t ktime_get_update_offsets(ktime_t *offs_real, ktime_t *offs_boot)
+ktime_t ktime_get_update_offsets(ktime_t *offs_real, ktime_t *offs_boot,
+                                                        ktime_t *offs_tai)
 {
         struct timekeeper *tk = &timekeeper;
         ktime_t now;
@@ -1554,6 +1571,7 @@ ktime_t ktime_get_update_offsets(ktime_t *offs_real, ktime_t *offs_boot)
 
                 *offs_real = tk->offs_real;
                 *offs_boot = tk->offs_boot;
+                *offs_tai = tk->offs_tai;
         } while (read_seqretry(&tk->lock, seq));
 
         now = ktime_add_ns(ktime_set(secs, 0), nsecs);