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-rw-r--r--Documentation/ptp/testptp.c6
-rw-r--r--arch/x86/include/asm/cpufeature.h2
-rw-r--r--arch/x86/include/asm/tsc.h2
-rw-r--r--arch/x86/kernel/tsc.c59
-rw-r--r--drivers/net/ethernet/intel/Kconfig9
-rw-r--r--drivers/net/ethernet/intel/e1000e/defines.h5
-rw-r--r--drivers/net/ethernet/intel/e1000e/ptp.c85
-rw-r--r--drivers/net/ethernet/intel/e1000e/regs.h4
-rw-r--r--drivers/ptp/ptp_chardev.c27
-rw-r--r--include/linux/pps_kernel.h17
-rw-r--r--include/linux/ptp_clock_kernel.h8
-rw-r--r--include/linux/timekeeper_internal.h2
-rw-r--r--include/linux/timekeeping.h58
-rw-r--r--include/uapi/linux/ptp_clock.h13
-rw-r--r--kernel/time/timekeeping.c286
15 files changed, 543 insertions, 40 deletions
diff --git a/Documentation/ptp/testptp.c b/Documentation/ptp/testptp.c
index 6c6247aaa7b9..d99012f41602 100644
--- a/Documentation/ptp/testptp.c
+++ b/Documentation/ptp/testptp.c
@@ -277,13 +277,15 @@ int main(int argc, char *argv[])
" %d external time stamp channels\n"
" %d programmable periodic signals\n"
" %d pulse per second\n"
- " %d programmable pins\n",
+ " %d programmable pins\n"
+ " %d cross timestamping\n",
caps.max_adj,
caps.n_alarm,
caps.n_ext_ts,
caps.n_per_out,
caps.pps,
- caps.n_pins);
+ caps.n_pins,
+ caps.cross_timestamping);
}
}
diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h
index 7ad8c9464297..ff557b49ab77 100644
--- a/arch/x86/include/asm/cpufeature.h
+++ b/arch/x86/include/asm/cpufeature.h
@@ -85,7 +85,7 @@
#define X86_FEATURE_P4 ( 3*32+ 7) /* "" P4 */
#define X86_FEATURE_CONSTANT_TSC ( 3*32+ 8) /* TSC ticks at a constant rate */
#define X86_FEATURE_UP ( 3*32+ 9) /* smp kernel running on up */
-/* free, was #define X86_FEATURE_FXSAVE_LEAK ( 3*32+10) * "" FXSAVE leaks FOP/FIP/FOP */
+#define X86_FEATURE_ART (3*32+10) /* Platform has always running timer (ART) */
#define X86_FEATURE_ARCH_PERFMON ( 3*32+11) /* Intel Architectural PerfMon */
#define X86_FEATURE_PEBS ( 3*32+12) /* Precise-Event Based Sampling */
#define X86_FEATURE_BTS ( 3*32+13) /* Branch Trace Store */
diff --git a/arch/x86/include/asm/tsc.h b/arch/x86/include/asm/tsc.h
index 6d7c5479bcea..174c4212780a 100644
--- a/arch/x86/include/asm/tsc.h
+++ b/arch/x86/include/asm/tsc.h
@@ -29,6 +29,8 @@ static inline cycles_t get_cycles(void)
return rdtsc();
}
+extern struct system_counterval_t convert_art_to_tsc(cycle_t art);
+
extern void tsc_init(void);
extern void mark_tsc_unstable(char *reason);
extern int unsynchronized_tsc(void);
diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index 3d743da828d3..80d761e420c5 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -43,6 +43,11 @@ static DEFINE_STATIC_KEY_FALSE(__use_tsc);
int tsc_clocksource_reliable;
+static u32 art_to_tsc_numerator;
+static u32 art_to_tsc_denominator;
+static u64 art_to_tsc_offset;
+struct clocksource *art_related_clocksource;
+
/*
* Use a ring-buffer like data structure, where a writer advances the head by
* writing a new data entry and a reader advances the tail when it observes a
@@ -964,6 +969,37 @@ core_initcall(cpufreq_tsc);
#endif /* CONFIG_CPU_FREQ */
+#define ART_CPUID_LEAF (0x15)
+#define ART_MIN_DENOMINATOR (1)
+
+
+/*
+ * If ART is present detect the numerator:denominator to convert to TSC
+ */
+static void detect_art(void)
+{
+ unsigned int unused[2];
+
+ if (boot_cpu_data.cpuid_level < ART_CPUID_LEAF)
+ return;
+
+ cpuid(ART_CPUID_LEAF, &art_to_tsc_denominator,
+ &art_to_tsc_numerator, unused, unused+1);
+
+ /* Don't enable ART in a VM, non-stop TSC required */
+ if (boot_cpu_has(X86_FEATURE_HYPERVISOR) ||
+ !boot_cpu_has(X86_FEATURE_NONSTOP_TSC) ||
+ art_to_tsc_denominator < ART_MIN_DENOMINATOR)
+ return;
+
+ if (rdmsrl_safe(MSR_IA32_TSC_ADJUST, &art_to_tsc_offset))
+ return;
+
+ /* Make this sticky over multiple CPU init calls */
+ setup_force_cpu_cap(X86_FEATURE_ART);
+}
+
+
/* clocksource code */
static struct clocksource clocksource_tsc;
@@ -1071,6 +1107,25 @@ int unsynchronized_tsc(void)
return 0;
}
+/*
+ * Convert ART to TSC given numerator/denominator found in detect_art()
+ */
+struct system_counterval_t convert_art_to_tsc(cycle_t art)
+{
+ u64 tmp, res, rem;
+
+ rem = do_div(art, art_to_tsc_denominator);
+
+ res = art * art_to_tsc_numerator;
+ tmp = rem * art_to_tsc_numerator;
+
+ do_div(tmp, art_to_tsc_denominator);
+ res += tmp + art_to_tsc_offset;
+
+ return (struct system_counterval_t) {.cs = art_related_clocksource,
+ .cycles = res};
+}
+EXPORT_SYMBOL(convert_art_to_tsc);
static void tsc_refine_calibration_work(struct work_struct *work);
static DECLARE_DELAYED_WORK(tsc_irqwork, tsc_refine_calibration_work);
@@ -1142,6 +1197,8 @@ static void tsc_refine_calibration_work(struct work_struct *work)
(unsigned long)tsc_khz % 1000);
out:
+ if (boot_cpu_has(X86_FEATURE_ART))
+ art_related_clocksource = &clocksource_tsc;
clocksource_register_khz(&clocksource_tsc, tsc_khz);
}
@@ -1235,6 +1292,8 @@ void __init tsc_init(void)
mark_tsc_unstable("TSCs unsynchronized");
check_system_tsc_reliable();
+
+ detect_art();
}
#ifdef CONFIG_SMP
diff --git a/drivers/net/ethernet/intel/Kconfig b/drivers/net/ethernet/intel/Kconfig
index fa593dd3efe1..3772f3ac956e 100644
--- a/drivers/net/ethernet/intel/Kconfig
+++ b/drivers/net/ethernet/intel/Kconfig
@@ -83,6 +83,15 @@ config E1000E
To compile this driver as a module, choose M here. The module
will be called e1000e.
+config E1000E_HWTS
+ bool "Support HW cross-timestamp on PCH devices"
+ default y
+ depends on E1000E && X86
+ ---help---
+ Say Y to enable hardware supported cross-timestamping on PCH
+ devices. The cross-timestamp is available through the PTP clock
+ driver precise cross-timestamp ioctl (PTP_SYS_OFFSET_PRECISE).
+
config IGB
tristate "Intel(R) 82575/82576 PCI-Express Gigabit Ethernet support"
depends on PCI
diff --git a/drivers/net/ethernet/intel/e1000e/defines.h b/drivers/net/ethernet/intel/e1000e/defines.h
index f7c7804d79e5..0641c0098738 100644
--- a/drivers/net/ethernet/intel/e1000e/defines.h
+++ b/drivers/net/ethernet/intel/e1000e/defines.h
@@ -528,6 +528,11 @@
#define E1000_RXCW_C 0x20000000 /* Receive config */
#define E1000_RXCW_SYNCH 0x40000000 /* Receive config synch */
+/* HH Time Sync */
+#define E1000_TSYNCTXCTL_MAX_ALLOWED_DLY_MASK 0x0000F000 /* max delay */
+#define E1000_TSYNCTXCTL_SYNC_COMP 0x40000000 /* sync complete */
+#define E1000_TSYNCTXCTL_START_SYNC 0x80000000 /* initiate sync */
+
#define E1000_TSYNCTXCTL_VALID 0x00000001 /* Tx timestamp valid */
#define E1000_TSYNCTXCTL_ENABLED 0x00000010 /* enable Tx timestamping */
diff --git a/drivers/net/ethernet/intel/e1000e/ptp.c b/drivers/net/ethernet/intel/e1000e/ptp.c
index 25a0ad5102d6..e2ff3ef75d5d 100644
--- a/drivers/net/ethernet/intel/e1000e/ptp.c
+++ b/drivers/net/ethernet/intel/e1000e/ptp.c
@@ -26,6 +26,12 @@
#include "e1000.h"
+#ifdef CONFIG_E1000E_HWTS
+#include <linux/clocksource.h>
+#include <linux/ktime.h>
+#include <asm/tsc.h>
+#endif
+
/**
* e1000e_phc_adjfreq - adjust the frequency of the hardware clock
* @ptp: ptp clock structure
@@ -98,6 +104,78 @@ static int e1000e_phc_adjtime(struct ptp_clock_info *ptp, s64 delta)
return 0;
}
+#ifdef CONFIG_E1000E_HWTS
+#define MAX_HW_WAIT_COUNT (3)
+
+/**
+ * e1000e_phc_get_syncdevicetime - Callback given to timekeeping code reads system/device registers
+ * @device: current device time
+ * @system: system counter value read synchronously with device time
+ * @ctx: context provided by timekeeping code
+ *
+ * Read device and system (ART) clock simultaneously and return the corrected
+ * clock values in ns.
+ **/
+static int e1000e_phc_get_syncdevicetime(ktime_t *device,
+ struct system_counterval_t *system,
+ void *ctx)
+{
+ struct e1000_adapter *adapter = (struct e1000_adapter *)ctx;
+ struct e1000_hw *hw = &adapter->hw;
+ unsigned long flags;
+ int i;
+ u32 tsync_ctrl;
+ cycle_t dev_cycles;
+ cycle_t sys_cycles;
+
+ tsync_ctrl = er32(TSYNCTXCTL);
+ tsync_ctrl |= E1000_TSYNCTXCTL_START_SYNC |
+ E1000_TSYNCTXCTL_MAX_ALLOWED_DLY_MASK;
+ ew32(TSYNCTXCTL, tsync_ctrl);
+ for (i = 0; i < MAX_HW_WAIT_COUNT; ++i) {
+ udelay(1);
+ tsync_ctrl = er32(TSYNCTXCTL);
+ if (tsync_ctrl & E1000_TSYNCTXCTL_SYNC_COMP)
+ break;
+ }
+
+ if (i == MAX_HW_WAIT_COUNT)
+ return -ETIMEDOUT;
+
+ dev_cycles = er32(SYSSTMPH);
+ dev_cycles <<= 32;
+ dev_cycles |= er32(SYSSTMPL);
+ spin_lock_irqsave(&adapter->systim_lock, flags);
+ *device = ns_to_ktime(timecounter_cyc2time(&adapter->tc, dev_cycles));
+ spin_unlock_irqrestore(&adapter->systim_lock, flags);
+
+ sys_cycles = er32(PLTSTMPH);
+ sys_cycles <<= 32;
+ sys_cycles |= er32(PLTSTMPL);
+ *system = convert_art_to_tsc(sys_cycles);
+
+ return 0;
+}
+
+/**
+ * e1000e_phc_getsynctime - Reads the current system/device cross timestamp
+ * @ptp: ptp clock structure
+ * @cts: structure containing timestamp
+ *
+ * Read device and system (ART) clock simultaneously and return the scaled
+ * clock values in ns.
+ **/
+static int e1000e_phc_getcrosststamp(struct ptp_clock_info *ptp,
+ struct system_device_crosststamp *xtstamp)
+{
+ struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
+ ptp_clock_info);
+
+ return get_device_system_crosststamp(e1000e_phc_get_syncdevicetime,
+ adapter, NULL, xtstamp);
+}
+#endif/*CONFIG_E1000E_HWTS*/
+
/**
* e1000e_phc_gettime - Reads the current time from the hardware clock
* @ptp: ptp clock structure
@@ -236,6 +314,13 @@ void e1000e_ptp_init(struct e1000_adapter *adapter)
break;
}
+#ifdef CONFIG_E1000E_HWTS
+ /* CPU must have ART and GBe must be from Sunrise Point or greater */
+ if (hw->mac.type >= e1000_pch_spt && boot_cpu_has(X86_FEATURE_ART))
+ adapter->ptp_clock_info.getcrosststamp =
+ e1000e_phc_getcrosststamp;
+#endif/*CONFIG_E1000E_HWTS*/
+
INIT_DELAYED_WORK(&adapter->systim_overflow_work,
e1000e_systim_overflow_work);
diff --git a/drivers/net/ethernet/intel/e1000e/regs.h b/drivers/net/ethernet/intel/e1000e/regs.h
index 1d5e0b77062a..0cb4d365e5ad 100644
--- a/drivers/net/ethernet/intel/e1000e/regs.h
+++ b/drivers/net/ethernet/intel/e1000e/regs.h
@@ -245,6 +245,10 @@
#define E1000_SYSTIML 0x0B600 /* System time register Low - RO */
#define E1000_SYSTIMH 0x0B604 /* System time register High - RO */
#define E1000_TIMINCA 0x0B608 /* Increment attributes register - RW */
+#define E1000_SYSSTMPL 0x0B648 /* HH Timesync system stamp low register */
+#define E1000_SYSSTMPH 0x0B64C /* HH Timesync system stamp hi register */
+#define E1000_PLTSTMPL 0x0B640 /* HH Timesync platform stamp low register */
+#define E1000_PLTSTMPH 0x0B644 /* HH Timesync platform stamp hi register */
#define E1000_RXMTRL 0x0B634 /* Time sync Rx EtherType and Msg Type - RW */
#define E1000_RXUDP 0x0B638 /* Time Sync Rx UDP Port - RW */
diff --git a/drivers/ptp/ptp_chardev.c b/drivers/ptp/ptp_chardev.c
index da7bae991552..579fd65299a0 100644
--- a/drivers/ptp/ptp_chardev.c
+++ b/drivers/ptp/ptp_chardev.c
@@ -22,6 +22,7 @@
#include <linux/poll.h>
#include <linux/sched.h>
#include <linux/slab.h>
+#include <linux/timekeeping.h>
#include "ptp_private.h"
@@ -120,11 +121,13 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
struct ptp_clock_caps caps;
struct ptp_clock_request req;
struct ptp_sys_offset *sysoff = NULL;
+ struct ptp_sys_offset_precise precise_offset;
struct ptp_pin_desc pd;
struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
struct ptp_clock_info *ops = ptp->info;
struct ptp_clock_time *pct;
struct timespec64 ts;
+ struct system_device_crosststamp xtstamp;
int enable, err = 0;
unsigned int i, pin_index;
@@ -138,6 +141,7 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
caps.n_per_out = ptp->info->n_per_out;
caps.pps = ptp->info->pps;
caps.n_pins = ptp->info->n_pins;
+ caps.cross_timestamping = ptp->info->getcrosststamp != NULL;
if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
err = -EFAULT;
break;
@@ -180,6 +184,29 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
err = ops->enable(ops, &req, enable);
break;
+ case PTP_SYS_OFFSET_PRECISE:
+ if (!ptp->info->getcrosststamp) {
+ err = -EOPNOTSUPP;
+ break;
+ }
+ err = ptp->info->getcrosststamp(ptp->info, &xtstamp);
+ if (err)
+ break;
+
+ ts = ktime_to_timespec64(xtstamp.device);
+ precise_offset.device.sec = ts.tv_sec;
+ precise_offset.device.nsec = ts.tv_nsec;
+ ts = ktime_to_timespec64(xtstamp.sys_realtime);
+ precise_offset.sys_realtime.sec = ts.tv_sec;
+ precise_offset.sys_realtime.nsec = ts.tv_nsec;
+ ts = ktime_to_timespec64(xtstamp.sys_monoraw);
+ precise_offset.sys_monoraw.sec = ts.tv_sec;
+ precise_offset.sys_monoraw.nsec = ts.tv_nsec;
+ if (copy_to_user((void __user *)arg, &precise_offset,
+ sizeof(precise_offset)))
+ err = -EFAULT;
+ break;
+
case PTP_SYS_OFFSET:
sysoff = kmalloc(sizeof(*sysoff), GFP_KERNEL);
if (!sysoff) {
diff --git a/include/linux/pps_kernel.h b/include/linux/pps_kernel.h
index 54bf1484d41f..35ac903956c7 100644
--- a/include/linux/pps_kernel.h
+++ b/include/linux/pps_kernel.h
@@ -111,22 +111,17 @@ static inline void timespec_to_pps_ktime(struct pps_ktime *kt,
kt->nsec = ts.tv_nsec;
}
-#ifdef CONFIG_NTP_PPS
-
static inline void pps_get_ts(struct pps_event_time *ts)
{
- ktime_get_raw_and_real_ts64(&ts->ts_raw, &ts->ts_real);
-}
+ struct system_time_snapshot snap;
-#else /* CONFIG_NTP_PPS */
-
-static inline void pps_get_ts(struct pps_event_time *ts)
-{
- ktime_get_real_ts64(&ts->ts_real);
+ ktime_get_snapshot(&snap);
+ ts->ts_real = ktime_to_timespec64(snap.real);
+#ifdef CONFIG_NTP_PPS
+ ts->ts_raw = ktime_to_timespec64(snap.raw);
+#endif
}
-#endif /* CONFIG_NTP_PPS */
-
/* Subtract known time delay from PPS event time(s) */
static inline void pps_sub_ts(struct pps_event_time *ts, struct timespec64 delta)
{
diff --git a/include/linux/ptp_clock_kernel.h b/include/linux/ptp_clock_kernel.h
index b8b73066d137..6b15e168148a 100644
--- a/include/linux/ptp_clock_kernel.h
+++ b/include/linux/ptp_clock_kernel.h
@@ -38,6 +38,7 @@ struct ptp_clock_request {
};
};
+struct system_device_crosststamp;
/**
* struct ptp_clock_info - decribes a PTP hardware clock
*
@@ -67,6 +68,11 @@ struct ptp_clock_request {
* @gettime64: Reads the current time from the hardware clock.
* parameter ts: Holds the result.
*
+ * @getcrosststamp: Reads the current time from the hardware clock and
+ * system clock simultaneously.
+ * parameter cts: Contains timestamp (device,system) pair,
+ * where system time is realtime and monotonic.
+ *
* @settime64: Set the current time on the hardware clock.
* parameter ts: Time value to set.
*
@@ -105,6 +111,8 @@ struct ptp_clock_info {
int (*adjfreq)(struct ptp_clock_info *ptp, s32 delta);
int (*adjtime)(struct ptp_clock_info *ptp, s64 delta);
int (*gettime64)(struct ptp_clock_info *ptp, struct timespec64 *ts);
+ int (*getcrosststamp)(struct ptp_clock_info *ptp,
+ struct system_device_crosststamp *cts);
int (*settime64)(struct ptp_clock_info *p, const struct timespec64 *ts);
int (*enable)(struct ptp_clock_info *ptp,
struct ptp_clock_request *request, int on);
diff --git a/include/linux/timekeeper_internal.h b/include/linux/timekeeper_internal.h
index 25247220b4b7..e88005459035 100644
--- a/include/linux/timekeeper_internal.h
+++ b/include/linux/timekeeper_internal.h
@@ -50,6 +50,7 @@ struct tk_read_base {
* @offs_tai: Offset clock monotonic -> clock tai
* @tai_offset: The current UTC to TAI offset in seconds
* @clock_was_set_seq: The sequence number of clock was set events
+ * @cs_was_changed_seq: The sequence number of clocksource change events
* @next_leap_ktime: CLOCK_MONOTONIC time value of a pending leap-second
* @raw_time: Monotonic raw base time in timespec64 format
* @cycle_interval: Number of clock cycles in one NTP interval
@@ -91,6 +92,7 @@ struct timekeeper {
ktime_t offs_tai;
s32 tai_offset;
unsigned int clock_was_set_seq;
+ u8 cs_was_changed_seq;
ktime_t next_leap_ktime;
struct timespec64 raw_time;
diff --git a/include/linux/timekeeping.h b/include/linux/timekeeping.h
index ec89d846324c..96f37bee3bc1 100644
--- a/include/linux/timekeeping.h
+++ b/include/linux/timekeeping.h
@@ -267,6 +267,64 @@ extern void ktime_get_raw_and_real_ts64(struct timespec64 *ts_raw,
struct timespec64 *ts_real);
/*
+ * struct system_time_snapshot - simultaneous raw/real time capture with
+ * counter value
+ * @cycles: Clocksource counter value to produce the system times
+ * @real: Realtime system time
+ * @raw: Monotonic raw system time
+ * @clock_was_set_seq: The sequence number of clock was set events
+ * @cs_was_changed_seq: The sequence number of clocksource change events
+ */
+struct system_time_snapshot {
+ cycle_t cycles;
+ ktime_t real;
+ ktime_t raw;
+ unsigned int clock_was_set_seq;
+ u8 cs_was_changed_seq;
+};
+
+/*
+ * struct system_device_crosststamp - system/device cross-timestamp
+ * (syncronized capture)
+ * @device: Device time
+ * @sys_realtime: Realtime simultaneous with device time
+ * @sys_monoraw: Monotonic raw simultaneous with device time
+ */
+struct system_device_crosststamp {
+ ktime_t device;
+ ktime_t sys_realtime;
+ ktime_t sys_monoraw;
+};
+
+/*
+ * struct system_counterval_t - system counter value with the pointer to the
+ * corresponding clocksource
+ * @cycles: System counter value
+ * @cs: Clocksource corresponding to system counter value. Used by
+ * timekeeping code to verify comparibility of two cycle values
+ */
+struct system_counterval_t {
+ cycle_t cycles;
+ struct clocksource *cs;
+};
+
+/*
+ * Get cross timestamp between system clock and device clock
+ */
+extern int get_device_system_crosststamp(
+ int (*get_time_fn)(ktime_t *device_time,
+ struct system_counterval_t *system_counterval,
+ void *ctx),
+ void *ctx,
+ struct system_time_snapshot *history,
+ struct system_device_crosststamp *xtstamp);
+
+/*
+ * Simultaneously snapshot realtime and monotonic raw clocks
+ */
+extern void ktime_get_snapshot(struct system_time_snapshot *systime_snapshot);
+
+/*
* Persistent clock related interfaces
*/
extern int persistent_clock_is_local;
diff --git a/include/uapi/linux/ptp_clock.h b/include/uapi/linux/ptp_clock.h
index f0b7bfe5da92..ac6dded80ffa 100644
--- a/include/uapi/linux/ptp_clock.h
+++ b/include/uapi/linux/ptp_clock.h
@@ -51,7 +51,9 @@ struct ptp_clock_caps {
int n_per_out; /* Number of programmable periodic signals. */
int pps; /* Whether the clock supports a PPS callback. */
int n_pins; /* Number of input/output pins. */
- int rsv[14]; /* Reserved for future use. */
+ /* Whether the clock supports precise system-device cross timestamps */
+ int cross_timestamping;
+ int rsv[13]; /* Reserved for future use. */
};
struct ptp_extts_request {
@@ -81,6 +83,13 @@ struct ptp_sys_offset {
struct ptp_clock_time ts[2 * PTP_MAX_SAMPLES + 1];
};
+struct ptp_sys_offset_precise {
+ struct ptp_clock_time device;
+ struct ptp_clock_time sys_realtime;
+ struct ptp_clock_time sys_monoraw;
+ unsigned int rsv[4]; /* Reserved for future use. */
+};
+
enum ptp_pin_function {
PTP_PF_NONE,
PTP_PF_EXTTS,
@@ -124,6 +133,8 @@ struct ptp_pin_desc {
#define PTP_SYS_OFFSET _IOW(PTP_CLK_MAGIC, 5, struct ptp_sys_offset)
#define PTP_PIN_GETFUNC _IOWR(PTP_CLK_MAGIC, 6, struct ptp_pin_desc)
#define PTP_PIN_SETFUNC _IOW(PTP_CLK_MAGIC, 7, struct ptp_pin_desc)
+#define PTP_SYS_OFFSET_PRECISE \
+ _IOWR(PTP_CLK_MAGIC, 8, struct ptp_sys_offset_precise)
struct ptp_extts_event {
struct ptp_clock_time t; /* Time event occured. */
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 34b4cedfa80d..931b0b1a71e9 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -233,6 +233,7 @@ static void tk_setup_internals(struct timekeeper *tk, struct clocksource *clock)
u64 tmp, ntpinterval;
struct clocksource *old_clock;
+ ++tk->cs_was_changed_seq;
old_clock = tk->tkr_mono.clock;
tk->tkr_mono.clock = clock;
tk->tkr_mono.read = clock->read;
@@ -298,17 +299,34 @@ u32 (*arch_gettimeoffset)(void) = default_arch_gettimeoffset;
static inline u32 arch_gettimeoffset(void) { return 0; }
#endif
+static inline s64 timekeeping_delta_to_ns(struct tk_read_base *tkr,
+ cycle_t delta)
+{
+ s64 nsec;
+
+ nsec = delta * tkr->mult + tkr->xtime_nsec;
+ nsec >>= tkr->shift;
+
+ /* If arch requires, add in get_arch_timeoffset() */
+ return nsec + arch_gettimeoffset();
+}
+
static inline s64 timekeeping_get_ns(struct tk_read_base *tkr)
{
cycle_t delta;
- s64 nsec;
delta = timekeeping_get_delta(tkr);
+ return timekeeping_delta_to_ns(tkr, delta);
+}
- nsec = (delta * tkr->mult + tkr->xtime_nsec) >> tkr->shift;
+static inline s64 timekeeping_cycles_to_ns(struct tk_read_base *tkr,
+ cycle_t cycles)
+{
+ cycle_t delta;
- /* If arch requires, add in get_arch_timeoffset() */
- return nsec + arch_gettimeoffset();
+ /* calculate the delta since the last update_wall_time */
+ delta = clocksource_delta(cycles, tkr->cycle_last, tkr->mask);
+ return timekeeping_delta_to_ns(tkr, delta);
}
/**
@@ -857,44 +875,262 @@ time64_t __ktime_get_real_seconds(void)
return tk->xtime_sec;
}
+/**
+ * ktime_get_snapshot - snapshots the realtime/monotonic raw clocks with counter
+ * @systime_snapshot: pointer to struct receiving the system time snapshot
+ */
+void ktime_get_snapshot(struct system_time_snapshot *systime_snapshot)
+{
+ struct timekeeper *tk = &tk_core.timekeeper;
+ unsigned long seq;
+ ktime_t base_raw;
+ ktime_t base_real;
+ s64 nsec_raw;
+ s64 nsec_real;
+ cycle_t now;
-#ifdef CONFIG_NTP_PPS
+ WARN_ON_ONCE(timekeeping_suspended);
+
+ do {
+ seq = read_seqcount_begin(&tk_core.seq);
+
+ now = tk->tkr_mono.read(tk->tkr_mono.clock);
+ systime_snapshot->cs_was_changed_seq = tk->cs_was_changed_seq;
+ systime_snapshot->clock_was_set_seq = tk->clock_was_set_seq;
+ base_real = ktime_add(tk->tkr_mono.base,
+ tk_core.timekeeper.offs_real);
+ base_raw = tk->tkr_raw.base;
+ nsec_real = timekeeping_cycles_to_ns(&tk->tkr_mono, now);
+ nsec_raw = timekeeping_cycles_to_ns(&tk->tkr_raw, now);
+ } while (read_seqcount_retry(&tk_core.seq, seq));
+
+ systime_snapshot->cycles = now;
+ systime_snapshot->real = ktime_add_ns(base_real, nsec_real);
+ systime_snapshot->raw = ktime_add_ns(base_raw, nsec_raw);
+}
+EXPORT_SYMBOL_GPL(ktime_get_snapshot);
+
+/* Scale base by mult/div checking for overflow */
+static int scale64_check_overflow(u64 mult, u64 div, u64 *base)
+{
+ u64 tmp, rem;
+
+ tmp = div64_u64_rem(*base, div, &rem);
+
+ if (((int)sizeof(u64)*8 - fls64(mult) < fls64(tmp)) ||
+ ((int)sizeof(u64)*8 - fls64(mult) < fls64(rem)))
+ return -EOVERFLOW;
+ tmp *= mult;
+ rem *= mult;
+
+ do_div(rem, div);
+ *base = tmp + rem;
+ return 0;
+}
/**
- * ktime_get_raw_and_real_ts64 - get day and raw monotonic time in timespec format
- * @ts_raw: pointer to the timespec to be set to raw monotonic time
- * @ts_real: pointer to the timespec to be set to the time of day
+ * adjust_historical_crosststamp - adjust crosstimestamp previous to current interval
+ * @history: Snapshot representing start of history
+ * @partial_history_cycles: Cycle offset into history (fractional part)
+ * @total_history_cycles: Total history length in cycles
+ * @discontinuity: True indicates clock was set on history period
+ * @ts: Cross timestamp that should be adjusted using
+ * partial/total ratio
*
- * This function reads both the time of day and raw monotonic time at the
- * same time atomically and stores the resulting timestamps in timespec
- * format.
+ * Helper function used by get_device_system_crosststamp() to correct the
+ * crosstimestamp corresponding to the start of the current interval to the
+ * system counter value (timestamp point) provided by the driver. The
+ * total_history_* quantities are the total history starting at the provided
+ * reference point and ending at the start of the current interval. The cycle
+ * count between the driver timestamp point and the start of the current
+ * interval is partial_history_cycles.
*/
-void ktime_get_raw_and_real_ts64(struct timespec64 *ts_raw, struct timespec64 *ts_real)
+static int adjust_historical_crosststamp(struct system_time_snapshot *history,
+ cycle_t partial_history_cycles,
+ cycle_t total_history_cycles,
+ bool discontinuity,
+ struct system_device_crosststamp *ts)
{
struct timekeeper *tk = &tk_core.timekeeper;
- unsigned long seq;
- s64 nsecs_raw, nsecs_real;
+ u64 corr_raw, corr_real;
+ bool interp_forward;
+ int ret;
- WARN_ON_ONCE(timekeeping_suspended);
+ if (total_history_cycles == 0 || partial_history_cycles == 0)
+ return 0;
+
+ /* Interpolate shortest distance from beginning or end of history */
+ interp_forward = partial_history_cycles > total_history_cycles/2 ?
+ true : false;
+ partial_history_cycles = interp_forward ?
+ total_history_cycles - partial_history_cycles :
+ partial_history_cycles;
+
+ /*
+ * Scale the monotonic raw time delta by:
+ * partial_history_cycles / total_history_cycles
+ */
+ corr_raw = (u64)ktime_to_ns(
+ ktime_sub(ts->sys_monoraw, history->raw));
+ ret = scale64_check_overflow(partial_history_cycles,
+ total_history_cycles, &corr_raw);
+ if (ret)
+ return ret;
+
+ /*
+ * If there is a discontinuity in the history, scale monotonic raw
+ * correction by:
+ * mult(real)/mult(raw) yielding the realtime correction
+ * Otherwise, calculate the realtime correction similar to monotonic
+ * raw calculation
+ */
+ if (discontinuity) {
+ corr_real = mul_u64_u32_div
+ (corr_raw, tk->tkr_mono.mult, tk->tkr_raw.mult);
+ } else {
+ corr_real = (u64)ktime_to_ns(
+ ktime_sub(ts->sys_realtime, history->real));
+ ret = scale64_check_overflow(partial_history_cycles,
+ total_history_cycles, &corr_real);
+ if (ret)
+ return ret;
+ }
+
+ /* Fixup monotonic raw and real time time values */
+ if (interp_forward) {
+ ts->sys_monoraw = ktime_add_ns(history->raw, corr_raw);
+ ts->sys_realtime = ktime_add_ns(history->real, corr_real);
+ } else {
+ ts->sys_monoraw = ktime_sub_ns(ts->sys_monoraw, corr_raw);
+ ts->sys_realtime = ktime_sub_ns(ts->sys_realtime, corr_real);
+ }
+
+ return 0;
+}
+
+/*
+ * cycle_between - true if test occurs chronologically between before and after
+ */
+static bool cycle_between(cycle_t before, cycle_t test, cycle_t after)
+{
+ if (test > before && test < after)
+ return true;
+ if (test < before && before > after)
+ return true;
+ return false;
+}
+
+/**
+ * get_device_system_crosststamp - Synchronously capture system/device timestamp
+ * @get_time_fn: Callback to get simultaneous device time and
+ * system counter from the device driver
+ * @ctx: Context passed to get_time_fn()
+ * @history_begin: Historical reference point used to interpolate system
+ * time when counter provided by the driver is before the current interval
+ * @xtstamp: Receives simultaneously captured system and device time
+ *
+ * Reads a timestamp from a device and correlates it to system time
+ */
+int get_device_system_crosststamp(int (*get_time_fn)
+ (ktime_t *device_time,
+ struct system_counterval_t *sys_counterval,
+ void *ctx),
+ void *ctx,
+ struct system_time_snapshot *history_begin,
+ struct system_device_crosststamp *xtstamp)
+{
+ struct system_counterval_t system_counterval;
+ struct timekeeper *tk = &tk_core.timekeeper;
+ cycle_t cycles, now, interval_start;
+ unsigned int clock_was_set_seq;
+ ktime_t base_real, base_raw;
+ s64 nsec_real, nsec_raw;
+ u8 cs_was_changed_seq;
+ unsigned long seq;
+ bool do_interp;
+ int ret;
do {
seq = read_seqcount_begin(&tk_core.seq);
+ /*
+ * Try to synchronously capture device time and a system
+ * counter value calling back into the device driver
+ */
+ ret = get_time_fn(&xtstamp->device, &system_counterval, ctx);
+ if (ret)
+ return ret;
+
+ /*
+ * Verify that the clocksource associated with the captured
+ * system counter value is the same as the currently installed
+ * timekeeper clocksource
+ */
+ if (tk->tkr_mono.clock != system_counterval.cs)
+ return -ENODEV;
+ cycles = system_counterval.cycles;
- *ts_raw = tk->raw_time;
- ts_real->tv_sec = tk->xtime_sec;
- ts_real->tv_nsec = 0;
+ /*
+ * Check whether the system counter value provided by the
+ * device driver is on the current timekeeping interval.
+ */
+ now = tk->tkr_mono.read(tk->tkr_mono.clock);
+ interval_start = tk->tkr_mono.cycle_last;
+ if (!cycle_between(interval_start, cycles, now)) {
+ clock_was_set_seq = tk->clock_was_set_seq;
+ cs_was_changed_seq = tk->cs_was_changed_seq;
+ cycles = interval_start;
+ do_interp = true;
+ } else {
+ do_interp = false;
+ }
- nsecs_raw = timekeeping_get_ns(&tk->tkr_raw);
- nsecs_real = timekeeping_get_ns(&tk->tkr_mono);
+ base_real = ktime_add(tk->tkr_mono.base,
+ tk_core.timekeeper.offs_real);
+ base_raw = tk->tkr_raw.base;
+ nsec_real = timekeeping_cycles_to_ns(&tk->tkr_mono,
+ system_counterval.cycles);
+ nsec_raw = timekeeping_cycles_to_ns(&tk->tkr_raw,
+ system_counterval.cycles);
} while (read_seqcount_retry(&tk_core.seq, seq));
- timespec64_add_ns(ts_raw, nsecs_raw);
- timespec64_add_ns(ts_real, nsecs_real);
-}
-EXPORT_SYMBOL(ktime_get_raw_and_real_ts64);
+ xtstamp->sys_realtime = ktime_add_ns(base_real, nsec_real);
+ xtstamp->sys_monoraw = ktime_add_ns(base_raw, nsec_raw);
-#endif /* CONFIG_NTP_PPS */
+ /*
+ * Interpolate if necessary, adjusting back from the start of the
+ * current interval
+ */
+ if (do_interp) {
+ cycle_t partial_history_cycles, total_history_cycles;
+ bool discontinuity;
+
+ /*
+ * Check that the counter value occurs after the provided
+ * history reference and that the history doesn't cross a
+ * clocksource change
+ */
+ if (!history_begin ||
+ !cycle_between(history_begin->cycles,
+ system_counterval.cycles, cycles) ||
+ history_begin->cs_was_changed_seq != cs_was_changed_seq)
+ return -EINVAL;
+ partial_history_cycles = cycles - system_counterval.cycles;
+ total_history_cycles = cycles - history_begin->cycles;
+ discontinuity =
+ history_begin->clock_was_set_seq != clock_was_set_seq;
+
+ ret = adjust_historical_crosststamp(history_begin,
+ partial_history_cycles,
+ total_history_cycles,
+ discontinuity, xtstamp);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(get_device_system_crosststamp);
/**
* do_gettimeofday - Returns the time of day in a timeval
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-16 02:15:06 +0000