Commit f5f59336 authored by Linus Torvalds's avatar Linus Torvalds

Merge tag 'timers-core-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timekeeping updates from Thomas Gleixner:
 "Updates for timekeeping, timers and related drivers:

  Core:

   - Early boot support for the NMI safe timekeeper by utilizing
     local_clock() up to the point where timekeeping is initialized.
     This allows printk() to store multiple timestamps in the ringbuffer
     which is useful for coordinating dmesg information across a fleet
     of machines.

   - Provide a multi-timestamp accessor for printk()

   - Make timer init more robust by checking for invalid timer flags.

   - Comma vs semicolon fixes

  Drivers:

   - Support for new platforms in existing drivers (SP804 and Renesas
     CMT)

   - Comma vs semicolon fixes

* tag 'timers-core-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clocksource/drivers/armada-370-xp: Use semicolons rather than commas to separate statements
  clocksource/drivers/mps2-timer: Use semicolons rather than commas to separate statements
  timers: Mask invalid flags in do_init_timer()
  clocksource/drivers/sp804: Enable Hisilicon sp804 timer 64bit mode
  clocksource/drivers/sp804: Add support for Hisilicon sp804 timer
  clocksource/drivers/sp804: Support non-standard register offset
  clocksource/drivers/sp804: Prepare for support non-standard register offset
  clocksource/drivers/sp804: Remove a mismatched comment
  clocksource/drivers/sp804: Delete the leading "__" of some functions
  clocksource/drivers/sp804: Remove unused sp804_timer_disable() and timer-sp804.h
  clocksource/drivers/sp804: Cleanup clk_get_sys()
  dt-bindings: timer: renesas,cmt: Document r8a774e1 CMT support
  dt-bindings: timer: renesas,cmt: Document r8a7742 CMT support
  alarmtimer: Convert comma to semicolon
  timekeeping: Provide multi-timestamp accessor to NMI safe timekeeper
  timekeeping: Utilize local_clock() for NMI safe timekeeper during early boot
parents 20d49bfc 1b80043e
...@@ -39,6 +39,7 @@ properties: ...@@ -39,6 +39,7 @@ properties:
- items: - items:
- enum: - enum:
- renesas,r8a73a4-cmt0 # 32-bit CMT0 on R-Mobile APE6 - renesas,r8a73a4-cmt0 # 32-bit CMT0 on R-Mobile APE6
- renesas,r8a7742-cmt0 # 32-bit CMT0 on RZ/G1H
- renesas,r8a7743-cmt0 # 32-bit CMT0 on RZ/G1M - renesas,r8a7743-cmt0 # 32-bit CMT0 on RZ/G1M
- renesas,r8a7744-cmt0 # 32-bit CMT0 on RZ/G1N - renesas,r8a7744-cmt0 # 32-bit CMT0 on RZ/G1N
- renesas,r8a7745-cmt0 # 32-bit CMT0 on RZ/G1E - renesas,r8a7745-cmt0 # 32-bit CMT0 on RZ/G1E
...@@ -53,6 +54,7 @@ properties: ...@@ -53,6 +54,7 @@ properties:
- items: - items:
- enum: - enum:
- renesas,r8a73a4-cmt1 # 48-bit CMT1 on R-Mobile APE6 - renesas,r8a73a4-cmt1 # 48-bit CMT1 on R-Mobile APE6
- renesas,r8a7742-cmt1 # 48-bit CMT1 on RZ/G1H
- renesas,r8a7743-cmt1 # 48-bit CMT1 on RZ/G1M - renesas,r8a7743-cmt1 # 48-bit CMT1 on RZ/G1M
- renesas,r8a7744-cmt1 # 48-bit CMT1 on RZ/G1N - renesas,r8a7744-cmt1 # 48-bit CMT1 on RZ/G1N
- renesas,r8a7745-cmt1 # 48-bit CMT1 on RZ/G1E - renesas,r8a7745-cmt1 # 48-bit CMT1 on RZ/G1E
...@@ -69,6 +71,7 @@ properties: ...@@ -69,6 +71,7 @@ properties:
- renesas,r8a774a1-cmt0 # 32-bit CMT0 on RZ/G2M - renesas,r8a774a1-cmt0 # 32-bit CMT0 on RZ/G2M
- renesas,r8a774b1-cmt0 # 32-bit CMT0 on RZ/G2N - renesas,r8a774b1-cmt0 # 32-bit CMT0 on RZ/G2N
- renesas,r8a774c0-cmt0 # 32-bit CMT0 on RZ/G2E - renesas,r8a774c0-cmt0 # 32-bit CMT0 on RZ/G2E
- renesas,r8a774e1-cmt0 # 32-bit CMT0 on RZ/G2H
- renesas,r8a7795-cmt0 # 32-bit CMT0 on R-Car H3 - renesas,r8a7795-cmt0 # 32-bit CMT0 on R-Car H3
- renesas,r8a7796-cmt0 # 32-bit CMT0 on R-Car M3-W - renesas,r8a7796-cmt0 # 32-bit CMT0 on R-Car M3-W
- renesas,r8a77965-cmt0 # 32-bit CMT0 on R-Car M3-N - renesas,r8a77965-cmt0 # 32-bit CMT0 on R-Car M3-N
...@@ -83,6 +86,7 @@ properties: ...@@ -83,6 +86,7 @@ properties:
- renesas,r8a774a1-cmt1 # 48-bit CMT on RZ/G2M - renesas,r8a774a1-cmt1 # 48-bit CMT on RZ/G2M
- renesas,r8a774b1-cmt1 # 48-bit CMT on RZ/G2N - renesas,r8a774b1-cmt1 # 48-bit CMT on RZ/G2N
- renesas,r8a774c0-cmt1 # 48-bit CMT on RZ/G2E - renesas,r8a774c0-cmt1 # 48-bit CMT on RZ/G2E
- renesas,r8a774e1-cmt1 # 48-bit CMT on RZ/G2H
- renesas,r8a7795-cmt1 # 48-bit CMT on R-Car H3 - renesas,r8a7795-cmt1 # 48-bit CMT on R-Car H3
- renesas,r8a7796-cmt1 # 48-bit CMT on R-Car M3-W - renesas,r8a7796-cmt1 # 48-bit CMT on R-Car M3-W
- renesas,r8a77965-cmt1 # 48-bit CMT on R-Car M3-N - renesas,r8a77965-cmt1 # 48-bit CMT on R-Car M3-N
......
...@@ -149,9 +149,9 @@ static int __init mps2_clockevent_init(struct device_node *np) ...@@ -149,9 +149,9 @@ static int __init mps2_clockevent_init(struct device_node *np)
ce->clkevt.rating = 200; ce->clkevt.rating = 200;
ce->clkevt.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT; ce->clkevt.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT;
ce->clkevt.cpumask = cpu_possible_mask; ce->clkevt.cpumask = cpu_possible_mask;
ce->clkevt.set_state_shutdown = mps2_timer_shutdown, ce->clkevt.set_state_shutdown = mps2_timer_shutdown;
ce->clkevt.set_state_periodic = mps2_timer_set_periodic, ce->clkevt.set_state_periodic = mps2_timer_set_periodic;
ce->clkevt.set_state_oneshot = mps2_timer_shutdown, ce->clkevt.set_state_oneshot = mps2_timer_shutdown;
ce->clkevt.set_next_event = mps2_timer_set_next_event; ce->clkevt.set_next_event = mps2_timer_set_next_event;
/* Ensure timer is disabled */ /* Ensure timer is disabled */
......
...@@ -181,12 +181,12 @@ static int armada_370_xp_timer_starting_cpu(unsigned int cpu) ...@@ -181,12 +181,12 @@ static int armada_370_xp_timer_starting_cpu(unsigned int cpu)
clr = TIMER0_25MHZ; clr = TIMER0_25MHZ;
local_timer_ctrl_clrset(clr, set); local_timer_ctrl_clrset(clr, set);
evt->name = "armada_370_xp_per_cpu_tick", evt->name = "armada_370_xp_per_cpu_tick";
evt->features = CLOCK_EVT_FEAT_ONESHOT | evt->features = CLOCK_EVT_FEAT_ONESHOT |
CLOCK_EVT_FEAT_PERIODIC; CLOCK_EVT_FEAT_PERIODIC;
evt->shift = 32, evt->shift = 32;
evt->rating = 300, evt->rating = 300;
evt->set_next_event = armada_370_xp_clkevt_next_event, evt->set_next_event = armada_370_xp_clkevt_next_event;
evt->set_state_shutdown = armada_370_xp_clkevt_shutdown; evt->set_state_shutdown = armada_370_xp_clkevt_shutdown;
evt->set_state_periodic = armada_370_xp_clkevt_set_periodic; evt->set_state_periodic = armada_370_xp_clkevt_set_periodic;
evt->set_state_oneshot = armada_370_xp_clkevt_shutdown; evt->set_state_oneshot = armada_370_xp_clkevt_shutdown;
......
...@@ -10,6 +10,7 @@ ...@@ -10,6 +10,7 @@
* *
* Every SP804 contains two identical timers. * Every SP804 contains two identical timers.
*/ */
#define NR_TIMERS 2
#define TIMER_1_BASE 0x00 #define TIMER_1_BASE 0x00
#define TIMER_2_BASE 0x20 #define TIMER_2_BASE 0x20
...@@ -29,3 +30,34 @@ ...@@ -29,3 +30,34 @@
#define TIMER_RIS 0x10 /* CVR ro */ #define TIMER_RIS 0x10 /* CVR ro */
#define TIMER_MIS 0x14 /* CVR ro */ #define TIMER_MIS 0x14 /* CVR ro */
#define TIMER_BGLOAD 0x18 /* CVR rw */ #define TIMER_BGLOAD 0x18 /* CVR rw */
struct sp804_timer {
int load;
int load_h;
int value;
int value_h;
int ctrl;
int intclr;
int ris;
int mis;
int bgload;
int bgload_h;
int timer_base[NR_TIMERS];
int width;
};
struct sp804_clkevt {
void __iomem *base;
void __iomem *load;
void __iomem *load_h;
void __iomem *value;
void __iomem *value_h;
void __iomem *ctrl;
void __iomem *intclr;
void __iomem *ris;
void __iomem *mis;
void __iomem *bgload;
void __iomem *bgload_h;
unsigned long reload;
int width;
};
This diff is collapsed.
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __CLKSOURCE_TIMER_SP804_H
#define __CLKSOURCE_TIMER_SP804_H
struct clk;
int __sp804_clocksource_and_sched_clock_init(void __iomem *,
const char *, struct clk *, int);
int __sp804_clockevents_init(void __iomem *, unsigned int,
struct clk *, const char *);
void sp804_timer_disable(void __iomem *);
static inline void sp804_clocksource_init(void __iomem *base, const char *name)
{
__sp804_clocksource_and_sched_clock_init(base, name, NULL, 0);
}
static inline void sp804_clocksource_and_sched_clock_init(void __iomem *base,
const char *name)
{
__sp804_clocksource_and_sched_clock_init(base, name, NULL, 1);
}
static inline void sp804_clockevents_init(void __iomem *base, unsigned int irq, const char *name)
{
__sp804_clockevents_init(base, irq, NULL, name);
}
#endif
...@@ -222,6 +222,18 @@ extern bool timekeeping_rtc_skipresume(void); ...@@ -222,6 +222,18 @@ extern bool timekeeping_rtc_skipresume(void);
extern void timekeeping_inject_sleeptime64(const struct timespec64 *delta); extern void timekeeping_inject_sleeptime64(const struct timespec64 *delta);
/*
* struct ktime_timestanps - Simultaneous mono/boot/real timestamps
* @mono: Monotonic timestamp
* @boot: Boottime timestamp
* @real: Realtime timestamp
*/
struct ktime_timestamps {
u64 mono;
u64 boot;
u64 real;
};
/** /**
* struct system_time_snapshot - simultaneous raw/real time capture with * struct system_time_snapshot - simultaneous raw/real time capture with
* counter value * counter value
...@@ -280,6 +292,9 @@ extern int get_device_system_crosststamp( ...@@ -280,6 +292,9 @@ extern int get_device_system_crosststamp(
*/ */
extern void ktime_get_snapshot(struct system_time_snapshot *systime_snapshot); extern void ktime_get_snapshot(struct system_time_snapshot *systime_snapshot);
/* NMI safe mono/boot/realtime timestamps */
extern void ktime_get_fast_timestamps(struct ktime_timestamps *snap);
/* /*
* Persistent clock related interfaces * Persistent clock related interfaces
*/ */
......
...@@ -67,6 +67,7 @@ struct timer_list { ...@@ -67,6 +67,7 @@ struct timer_list {
#define TIMER_DEFERRABLE 0x00080000 #define TIMER_DEFERRABLE 0x00080000
#define TIMER_PINNED 0x00100000 #define TIMER_PINNED 0x00100000
#define TIMER_IRQSAFE 0x00200000 #define TIMER_IRQSAFE 0x00200000
#define TIMER_INIT_FLAGS (TIMER_DEFERRABLE | TIMER_PINNED | TIMER_IRQSAFE)
#define TIMER_ARRAYSHIFT 22 #define TIMER_ARRAYSHIFT 22
#define TIMER_ARRAYMASK 0xFFC00000 #define TIMER_ARRAYMASK 0xFFC00000
......
...@@ -908,7 +908,7 @@ static int __init alarmtimer_init(void) ...@@ -908,7 +908,7 @@ static int __init alarmtimer_init(void)
/* Initialize alarm bases */ /* Initialize alarm bases */
alarm_bases[ALARM_REALTIME].base_clockid = CLOCK_REALTIME; alarm_bases[ALARM_REALTIME].base_clockid = CLOCK_REALTIME;
alarm_bases[ALARM_REALTIME].get_ktime = &ktime_get_real; alarm_bases[ALARM_REALTIME].get_ktime = &ktime_get_real;
alarm_bases[ALARM_REALTIME].get_timespec = ktime_get_real_ts64, alarm_bases[ALARM_REALTIME].get_timespec = ktime_get_real_ts64;
alarm_bases[ALARM_BOOTTIME].base_clockid = CLOCK_BOOTTIME; alarm_bases[ALARM_BOOTTIME].base_clockid = CLOCK_BOOTTIME;
alarm_bases[ALARM_BOOTTIME].get_ktime = &ktime_get_boottime; alarm_bases[ALARM_BOOTTIME].get_ktime = &ktime_get_boottime;
alarm_bases[ALARM_BOOTTIME].get_timespec = get_boottime_timespec; alarm_bases[ALARM_BOOTTIME].get_timespec = get_boottime_timespec;
......
...@@ -54,6 +54,9 @@ static struct { ...@@ -54,6 +54,9 @@ static struct {
static struct timekeeper shadow_timekeeper; static struct timekeeper shadow_timekeeper;
/* flag for if timekeeping is suspended */
int __read_mostly timekeeping_suspended;
/** /**
* struct tk_fast - NMI safe timekeeper * struct tk_fast - NMI safe timekeeper
* @seq: Sequence counter for protecting updates. The lowest bit * @seq: Sequence counter for protecting updates. The lowest bit
...@@ -73,28 +76,42 @@ static u64 cycles_at_suspend; ...@@ -73,28 +76,42 @@ static u64 cycles_at_suspend;
static u64 dummy_clock_read(struct clocksource *cs) static u64 dummy_clock_read(struct clocksource *cs)
{ {
return cycles_at_suspend; if (timekeeping_suspended)
return cycles_at_suspend;
return local_clock();
} }
static struct clocksource dummy_clock = { static struct clocksource dummy_clock = {
.read = dummy_clock_read, .read = dummy_clock_read,
}; };
/*
* Boot time initialization which allows local_clock() to be utilized
* during early boot when clocksources are not available. local_clock()
* returns nanoseconds already so no conversion is required, hence mult=1
* and shift=0. When the first proper clocksource is installed then
* the fast time keepers are updated with the correct values.
*/
#define FAST_TK_INIT \
{ \
.clock = &dummy_clock, \
.mask = CLOCKSOURCE_MASK(64), \
.mult = 1, \
.shift = 0, \
}
static struct tk_fast tk_fast_mono ____cacheline_aligned = { static struct tk_fast tk_fast_mono ____cacheline_aligned = {
.seq = SEQCNT_RAW_SPINLOCK_ZERO(tk_fast_mono.seq, &timekeeper_lock), .seq = SEQCNT_RAW_SPINLOCK_ZERO(tk_fast_mono.seq, &timekeeper_lock),
.base[0] = { .clock = &dummy_clock, }, .base[0] = FAST_TK_INIT,
.base[1] = { .clock = &dummy_clock, }, .base[1] = FAST_TK_INIT,
}; };
static struct tk_fast tk_fast_raw ____cacheline_aligned = { static struct tk_fast tk_fast_raw ____cacheline_aligned = {
.seq = SEQCNT_RAW_SPINLOCK_ZERO(tk_fast_raw.seq, &timekeeper_lock), .seq = SEQCNT_RAW_SPINLOCK_ZERO(tk_fast_raw.seq, &timekeeper_lock),
.base[0] = { .clock = &dummy_clock, }, .base[0] = FAST_TK_INIT,
.base[1] = { .clock = &dummy_clock, }, .base[1] = FAST_TK_INIT,
}; };
/* flag for if timekeeping is suspended */
int __read_mostly timekeeping_suspended;
static inline void tk_normalize_xtime(struct timekeeper *tk) static inline void tk_normalize_xtime(struct timekeeper *tk)
{ {
while (tk->tkr_mono.xtime_nsec >= ((u64)NSEC_PER_SEC << tk->tkr_mono.shift)) { while (tk->tkr_mono.xtime_nsec >= ((u64)NSEC_PER_SEC << tk->tkr_mono.shift)) {
...@@ -513,29 +530,29 @@ u64 notrace ktime_get_boot_fast_ns(void) ...@@ -513,29 +530,29 @@ u64 notrace ktime_get_boot_fast_ns(void)
} }
EXPORT_SYMBOL_GPL(ktime_get_boot_fast_ns); EXPORT_SYMBOL_GPL(ktime_get_boot_fast_ns);
/* /*
* See comment for __ktime_get_fast_ns() vs. timestamp ordering * See comment for __ktime_get_fast_ns() vs. timestamp ordering
*/ */
static __always_inline u64 __ktime_get_real_fast_ns(struct tk_fast *tkf) static __always_inline u64 __ktime_get_real_fast(struct tk_fast *tkf, u64 *mono)
{ {
struct tk_read_base *tkr; struct tk_read_base *tkr;
u64 basem, baser, delta;
unsigned int seq; unsigned int seq;
u64 now;
do { do {
seq = raw_read_seqcount_latch(&tkf->seq); seq = raw_read_seqcount_latch(&tkf->seq);
tkr = tkf->base + (seq & 0x01); tkr = tkf->base + (seq & 0x01);
now = ktime_to_ns(tkr->base_real); basem = ktime_to_ns(tkr->base);
baser = ktime_to_ns(tkr->base_real);
now += timekeeping_delta_to_ns(tkr, delta = timekeeping_delta_to_ns(tkr,
clocksource_delta( clocksource_delta(tk_clock_read(tkr),
tk_clock_read(tkr), tkr->cycle_last, tkr->mask));
tkr->cycle_last,
tkr->mask));
} while (read_seqcount_retry(&tkf->seq, seq)); } while (read_seqcount_retry(&tkf->seq, seq));
return now; if (mono)
*mono = basem + delta;
return baser + delta;
} }
/** /**
...@@ -543,10 +560,64 @@ static __always_inline u64 __ktime_get_real_fast_ns(struct tk_fast *tkf) ...@@ -543,10 +560,64 @@ static __always_inline u64 __ktime_get_real_fast_ns(struct tk_fast *tkf)
*/ */
u64 ktime_get_real_fast_ns(void) u64 ktime_get_real_fast_ns(void)
{ {
return __ktime_get_real_fast_ns(&tk_fast_mono); return __ktime_get_real_fast(&tk_fast_mono, NULL);
} }
EXPORT_SYMBOL_GPL(ktime_get_real_fast_ns); EXPORT_SYMBOL_GPL(ktime_get_real_fast_ns);
/**
* ktime_get_fast_timestamps: - NMI safe timestamps
* @snapshot: Pointer to timestamp storage
*
* Stores clock monotonic, boottime and realtime timestamps.
*
* Boot time is a racy access on 32bit systems if the sleep time injection
* happens late during resume and not in timekeeping_resume(). That could
* be avoided by expanding struct tk_read_base with boot offset for 32bit
* and adding more overhead to the update. As this is a hard to observe
* once per resume event which can be filtered with reasonable effort using
* the accurate mono/real timestamps, it's probably not worth the trouble.
*
* Aside of that it might be possible on 32 and 64 bit to observe the
* following when the sleep time injection happens late:
*
* CPU 0 CPU 1
* timekeeping_resume()
* ktime_get_fast_timestamps()
* mono, real = __ktime_get_real_fast()
* inject_sleep_time()
* update boot offset
* boot = mono + bootoffset;
*
* That means that boot time already has the sleep time adjustment, but
* real time does not. On the next readout both are in sync again.
*
* Preventing this for 64bit is not really feasible without destroying the
* careful cache layout of the timekeeper because the sequence count and
* struct tk_read_base would then need two cache lines instead of one.
*
* Access to the time keeper clock source is disabled accross the innermost
* steps of suspend/resume. The accessors still work, but the timestamps
* are frozen until time keeping is resumed which happens very early.
*
* For regular suspend/resume there is no observable difference vs. sched
* clock, but it might affect some of the nasty low level debug printks.
*
* OTOH, access to sched clock is not guaranteed accross suspend/resume on
* all systems either so it depends on the hardware in use.
*
* If that turns out to be a real problem then this could be mitigated by
* using sched clock in a similar way as during early boot. But it's not as
* trivial as on early boot because it needs some careful protection
* against the clock monotonic timestamp jumping backwards on resume.
*/
void ktime_get_fast_timestamps(struct ktime_timestamps *snapshot)
{
struct timekeeper *tk = &tk_core.timekeeper;
snapshot->real = __ktime_get_real_fast(&tk_fast_mono, &snapshot->mono);
snapshot->boot = snapshot->mono + ktime_to_ns(data_race(tk->offs_boot));
}
/** /**
* halt_fast_timekeeper - Prevent fast timekeeper from accessing clocksource. * halt_fast_timekeeper - Prevent fast timekeeper from accessing clocksource.
* @tk: Timekeeper to snapshot. * @tk: Timekeeper to snapshot.
......
...@@ -794,6 +794,8 @@ static void do_init_timer(struct timer_list *timer, ...@@ -794,6 +794,8 @@ static void do_init_timer(struct timer_list *timer,
{ {
timer->entry.pprev = NULL; timer->entry.pprev = NULL;
timer->function = func; timer->function = func;
if (WARN_ON_ONCE(flags & ~TIMER_INIT_FLAGS))
flags &= TIMER_INIT_FLAGS;
timer->flags = flags | raw_smp_processor_id(); timer->flags = flags | raw_smp_processor_id();
lockdep_init_map(&timer->lockdep_map, name, key, 0); lockdep_init_map(&timer->lockdep_map, name, key, 0);
} }
......
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