Merge tag 'timers-v6.5-rc1' of https://git.linaro.org/people/daniel.lezcano/linux into timers/core

Pull clockevent/source updates from Daniel Lezcano:

  - Fix memory leak on Cadence TTC at probe time (Feng Mingxi)

  - Use the pm_sleep_ptr macro for the Ingenic driver (Paul Cercueil)

  - Relocate the PMW timer Loongson from the mips arch directory to the
    drivers/clocksource (Keguang Zhang)

  - Use the same function names instead of using aliases and move data
    defined in the header to the driver directly as this one is the only
    user of the header file and remove this one on i.MX GPT (Uwe
    Kleine-König)

  - Convert Broadcom Kona family timer bindings to DT schema (Michael
     Kelley)

  - Add DT bindings for Ralink SoCs timer (Sergio Paracuellos)

1 files changed, 23 insertions, 31 deletions

diff --git a/drivers/clocksource/hyperv_timer.c b/drivers/clocksource/hyperv_timer.c
index bcd9042a0c9f4..9fc008c166361 100644
--- a/drivers/clocksource/hyperv_timer.c
+++ b/drivers/clocksource/hyperv_timer.c
@@ -475,15 +475,9 @@ static u64 notrace read_hv_clock_msr_cs(struct clocksource *arg)
 	return read_hv_clock_msr();
 }
 
-static u64 notrace read_hv_sched_clock_msr(void)
-{
-	return (read_hv_clock_msr() - hv_sched_clock_offset) *
-		(NSEC_PER_SEC / HV_CLOCK_HZ);
-}
-
 static struct clocksource hyperv_cs_msr = {
 	.name	= "hyperv_clocksource_msr",
-	.rating	= 500,
+	.rating	= 495,
 	.read	= read_hv_clock_msr_cs,
 	.mask	= CLOCKSOURCE_MASK(64),
 	.flags	= CLOCK_SOURCE_IS_CONTINUOUS,
@@ -513,7 +507,7 @@ static __always_inline void hv_setup_sched_clock(void *sched_clock)
 static __always_inline void hv_setup_sched_clock(void *sched_clock) {}
 #endif /* CONFIG_GENERIC_SCHED_CLOCK */
 
-static bool __init hv_init_tsc_clocksource(void)
+static void __init hv_init_tsc_clocksource(void)
 {
 	union hv_reference_tsc_msr tsc_msr;
 
@@ -524,17 +518,14 @@ static bool __init hv_init_tsc_clocksource(void)
 	 * Hyper-V Reference TSC rating, causing the generic TSC to be used.
 	 * TSC_INVARIANT is not offered on ARM64, so the Hyper-V Reference
 	 * TSC will be preferred over the virtualized ARM64 arch counter.
-	 * While the Hyper-V MSR clocksource won't be used since the
-	 * Reference TSC clocksource is present, change its rating as
-	 * well for consistency.
 	 */
 	if (ms_hyperv.features & HV_ACCESS_TSC_INVARIANT) {
 		hyperv_cs_tsc.rating = 250;
-		hyperv_cs_msr.rating = 250;
+		hyperv_cs_msr.rating = 245;
 	}
 
 	if (!(ms_hyperv.features & HV_MSR_REFERENCE_TSC_AVAILABLE))
-		return false;
+		return;
 
 	hv_read_reference_counter = read_hv_clock_tsc;
 
@@ -565,33 +556,34 @@ static bool __init hv_init_tsc_clocksource(void)
 
 	clocksource_register_hz(&hyperv_cs_tsc, NSEC_PER_SEC/100);
 
-	hv_sched_clock_offset = hv_read_reference_counter();
-	hv_setup_sched_clock(read_hv_sched_clock_tsc);
-
-	return true;
+	/*
+	 * If TSC is invariant, then let it stay as the sched clock since it
+	 * will be faster than reading the TSC page. But if not invariant, use
+	 * the TSC page so that live migrations across hosts with different
+	 * frequencies is handled correctly.
+	 */
+	if (!(ms_hyperv.features & HV_ACCESS_TSC_INVARIANT)) {
+		hv_sched_clock_offset = hv_read_reference_counter();
+		hv_setup_sched_clock(read_hv_sched_clock_tsc);
+	}
 }
 
 void __init hv_init_clocksource(void)
 {
 	/*
-	 * Try to set up the TSC page clocksource. If it succeeds, we're
-	 * done. Otherwise, set up the MSR clocksource.  At least one of
-	 * these will always be available except on very old versions of
-	 * Hyper-V on x86.  In that case we won't have a Hyper-V
+	 * Try to set up the TSC page clocksource, then the MSR clocksource.
+	 * At least one of these will always be available except on very old
+	 * versions of Hyper-V on x86.  In that case we won't have a Hyper-V
 	 * clocksource, but Linux will still run with a clocksource based
 	 * on the emulated PIT or LAPIC timer.
+	 *
+	 * Never use the MSR clocksource as sched clock.  It's too slow.
+	 * Better to use the native sched clock as the fallback.
 	 */
-	if (hv_init_tsc_clocksource())
-		return;
-
-	if (!(ms_hyperv.features & HV_MSR_TIME_REF_COUNT_AVAILABLE))
-		return;
-
-	hv_read_reference_counter = read_hv_clock_msr;
-	clocksource_register_hz(&hyperv_cs_msr, NSEC_PER_SEC/100);
+	hv_init_tsc_clocksource();
 
-	hv_sched_clock_offset = hv_read_reference_counter();
-	hv_setup_sched_clock(read_hv_sched_clock_msr);
+	if (ms_hyperv.features & HV_MSR_TIME_REF_COUNT_AVAILABLE)
+		clocksource_register_hz(&hyperv_cs_msr, NSEC_PER_SEC/100);
 }
 
 void __init hv_remap_tsc_clocksource(void)