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/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h index 9e0567f4c081..074b7604bd51 100644 --- a/arch/x86/include/asm/cpufeatures.h +++ b/arch/x86/include/asm/cpufeatures.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 5a6cb4684e0f..56380440d862 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/clocksource/Kconfig b/drivers/clocksource/Kconfig index 33db7406c0e2..c346be650892 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -160,6 +160,7 @@ config CLKSRC_EFM32 config CLKSRC_LPC32XX bool "Clocksource for LPC32XX" if COMPILE_TEST depends on GENERIC_CLOCKEVENTS && HAS_IOMEM + depends on ARM select CLKSRC_MMIO select CLKSRC_OF help diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c index c64d543d64bf..f0dd9d42bc7b 100644 --- a/drivers/clocksource/arm_arch_timer.c +++ b/drivers/clocksource/arm_arch_timer.c @@ -32,6 +32,14 @@ #define CNTTIDR 0x08 #define CNTTIDR_VIRT(n) (BIT(1) << ((n) * 4)) +#define CNTACR(n) (0x40 + ((n) * 4)) +#define CNTACR_RPCT BIT(0) +#define CNTACR_RVCT BIT(1) +#define CNTACR_RFRQ BIT(2) +#define CNTACR_RVOFF BIT(3) +#define CNTACR_RWVT BIT(4) +#define CNTACR_RWPT BIT(5) + #define CNTVCT_LO 0x08 #define CNTVCT_HI 0x0c #define CNTFRQ 0x10 @@ -266,10 +274,12 @@ static void __arch_timer_setup(unsigned type, if (arch_timer_use_virtual) { clk->irq = arch_timer_ppi[VIRT_PPI]; clk->set_state_shutdown = arch_timer_shutdown_virt; + clk->set_state_oneshot_stopped = arch_timer_shutdown_virt; clk->set_next_event = arch_timer_set_next_event_virt; } else { clk->irq = arch_timer_ppi[PHYS_SECURE_PPI]; clk->set_state_shutdown = arch_timer_shutdown_phys; + clk->set_state_oneshot_stopped = arch_timer_shutdown_phys; clk->set_next_event = arch_timer_set_next_event_phys; } } else { @@ -279,10 +289,12 @@ static void __arch_timer_setup(unsigned type, clk->cpumask = cpu_all_mask; if (arch_timer_mem_use_virtual) { clk->set_state_shutdown = arch_timer_shutdown_virt_mem; + clk->set_state_oneshot_stopped = arch_timer_shutdown_virt_mem; clk->set_next_event = arch_timer_set_next_event_virt_mem; } else { clk->set_state_shutdown = arch_timer_shutdown_phys_mem; + clk->set_state_oneshot_stopped = arch_timer_shutdown_phys_mem; clk->set_next_event = arch_timer_set_next_event_phys_mem; } @@ -757,7 +769,6 @@ static void __init arch_timer_mem_init(struct device_node *np) } cnttidr = readl_relaxed(cntctlbase + CNTTIDR); - iounmap(cntctlbase); /* * Try to find a virtual capable frame. Otherwise fall back to a @@ -765,20 +776,31 @@ static void __init arch_timer_mem_init(struct device_node *np) */ for_each_available_child_of_node(np, frame) { int n; + u32 cntacr; if (of_property_read_u32(frame, "frame-number", &n)) { pr_err("arch_timer: Missing frame-number\n"); - of_node_put(best_frame); of_node_put(frame); - return; + goto out; } - if (cnttidr & CNTTIDR_VIRT(n)) { + /* Try enabling everything, and see what sticks */ + cntacr = CNTACR_RFRQ | CNTACR_RWPT | CNTACR_RPCT | + CNTACR_RWVT | CNTACR_RVOFF | CNTACR_RVCT; + writel_relaxed(cntacr, cntctlbase + CNTACR(n)); + cntacr = readl_relaxed(cntctlbase + CNTACR(n)); + + if ((cnttidr & CNTTIDR_VIRT(n)) && + !(~cntacr & (CNTACR_RWVT | CNTACR_RVCT))) { of_node_put(best_frame); best_frame = frame; arch_timer_mem_use_virtual = true; break; } + + if (~cntacr & (CNTACR_RWPT | CNTACR_RPCT)) + continue; + of_node_put(best_frame); best_frame = of_node_get(frame); } @@ -786,24 +808,26 @@ static void __init arch_timer_mem_init(struct device_node *np) base = arch_counter_base = of_iomap(best_frame, 0); if (!base) { pr_err("arch_timer: Can't map frame's registers\n"); - of_node_put(best_frame); - return; + goto out; } if (arch_timer_mem_use_virtual) irq = irq_of_parse_and_map(best_frame, 1); else irq = irq_of_parse_and_map(best_frame, 0); - of_node_put(best_frame); + if (!irq) { pr_err("arch_timer: Frame missing %s irq", arch_timer_mem_use_virtual ? "virt" : "phys"); - return; + goto out; } arch_timer_detect_rate(base, np); arch_timer_mem_register(base, irq); arch_timer_common_init(); +out: + iounmap(cntctlbase); + of_node_put(best_frame); } CLOCKSOURCE_OF_DECLARE(armv7_arch_timer_mem, "arm,armv7-timer-mem", arch_timer_mem_init); diff --git a/drivers/clocksource/arm_global_timer.c b/drivers/clocksource/arm_global_timer.c index d189d8cb69f7..9df0d1699d22 100644 --- a/drivers/clocksource/arm_global_timer.c +++ b/drivers/clocksource/arm_global_timer.c @@ -16,6 +16,7 @@ #include #include #include +#include #include #include #include @@ -174,6 +175,7 @@ static int gt_clockevents_init(struct clock_event_device *clk) clk->set_state_shutdown = gt_clockevent_shutdown; clk->set_state_periodic = gt_clockevent_set_periodic; clk->set_state_oneshot = gt_clockevent_shutdown; + clk->set_state_oneshot_stopped = gt_clockevent_shutdown; clk->set_next_event = gt_clockevent_set_next_event; clk->cpumask = cpumask_of(cpu); clk->rating = 300; @@ -221,6 +223,21 @@ static u64 notrace gt_sched_clock_read(void) } #endif +static unsigned long gt_read_long(void) +{ + return readl_relaxed(gt_base + GT_COUNTER0); +} + +static struct delay_timer gt_delay_timer = { + .read_current_timer = gt_read_long, +}; + +static void __init gt_delay_timer_init(void) +{ + gt_delay_timer.freq = gt_clk_rate; + register_current_timer_delay(>_delay_timer); +} + static void __init gt_clocksource_init(void) { writel(0, gt_base + GT_CONTROL); @@ -317,6 +334,7 @@ static void __init global_timer_of_register(struct device_node *np) /* Immediately configure the timer on the boot CPU */ gt_clocksource_init(); gt_clockevents_init(this_cpu_ptr(gt_evt)); + gt_delay_timer_init(); return; diff --git a/drivers/clocksource/exynos_mct.c b/drivers/clocksource/exynos_mct.c index ff44082a0827..be09bc0b5e26 100644 --- a/drivers/clocksource/exynos_mct.c +++ b/drivers/clocksource/exynos_mct.c @@ -313,6 +313,7 @@ static struct clock_event_device mct_comp_device = { .set_state_periodic = mct_set_state_periodic, .set_state_shutdown = mct_set_state_shutdown, .set_state_oneshot = mct_set_state_shutdown, + .set_state_oneshot_stopped = mct_set_state_shutdown, .tick_resume = mct_set_state_shutdown, }; @@ -452,6 +453,7 @@ static int exynos4_local_timer_setup(struct mct_clock_event_device *mevt) evt->set_state_periodic = set_state_periodic; evt->set_state_shutdown = set_state_shutdown; evt->set_state_oneshot = set_state_shutdown; + evt->set_state_oneshot_stopped = set_state_shutdown; evt->tick_resume = set_state_shutdown; evt->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT; evt->rating = 450; diff --git a/drivers/clocksource/rockchip_timer.c b/drivers/clocksource/rockchip_timer.c index 8c77a529d0d4..b991b288c803 100644 --- a/drivers/clocksource/rockchip_timer.c +++ b/drivers/clocksource/rockchip_timer.c @@ -122,23 +122,23 @@ static void __init rk_timer_init(struct device_node *np) pclk = of_clk_get_by_name(np, "pclk"); if (IS_ERR(pclk)) { pr_err("Failed to get pclk for '%s'\n", TIMER_NAME); - return; + goto out_unmap; } if (clk_prepare_enable(pclk)) { pr_err("Failed to enable pclk for '%s'\n", TIMER_NAME); - return; + goto out_unmap; } timer_clk = of_clk_get_by_name(np, "timer"); if (IS_ERR(timer_clk)) { pr_err("Failed to get timer clock for '%s'\n", TIMER_NAME); - return; + goto out_timer_clk; } if (clk_prepare_enable(timer_clk)) { pr_err("Failed to enable timer clock\n"); - return; + goto out_timer_clk; } bc_timer.freq = clk_get_rate(timer_clk); @@ -146,7 +146,7 @@ static void __init rk_timer_init(struct device_node *np) irq = irq_of_parse_and_map(np, 0); if (!irq) { pr_err("Failed to map interrupts for '%s'\n", TIMER_NAME); - return; + goto out_irq; } ce->name = TIMER_NAME; @@ -164,10 +164,19 @@ static void __init rk_timer_init(struct device_node *np) ret = request_irq(irq, rk_timer_interrupt, IRQF_TIMER, TIMER_NAME, ce); if (ret) { pr_err("Failed to initialize '%s': %d\n", TIMER_NAME, ret); - return; + goto out_irq; } clockevents_config_and_register(ce, bc_timer.freq, 1, UINT_MAX); + + return; + +out_irq: + clk_disable_unprepare(timer_clk); +out_timer_clk: + clk_disable_unprepare(pclk); +out_unmap: + iounmap(bc_timer.base); } CLOCKSOURCE_OF_DECLARE(rk_timer, "rockchip,rk3288-timer", rk_timer_init); diff --git a/drivers/clocksource/time-lpc32xx.c b/drivers/clocksource/time-lpc32xx.c index 1316876b487a..daae61e8c820 100644 --- a/drivers/clocksource/time-lpc32xx.c +++ b/drivers/clocksource/time-lpc32xx.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include #include @@ -43,6 +44,7 @@ struct lpc32xx_clock_event_ddata { struct clock_event_device evtdev; void __iomem *base; + u32 ticks_per_jiffy; }; /* Needed for the sched clock */ @@ -53,6 +55,15 @@ static u64 notrace lpc32xx_read_sched_clock(void) return readl(clocksource_timer_counter); } +static unsigned long lpc32xx_delay_timer_read(void) +{ + return readl(clocksource_timer_counter); +} + +static struct delay_timer lpc32xx_delay_timer = { + .read_current_timer = lpc32xx_delay_timer_read, +}; + static int lpc32xx_clkevt_next_event(unsigned long delta, struct clock_event_device *evtdev) { @@ -60,14 +71,13 @@ static int lpc32xx_clkevt_next_event(unsigned long delta, container_of(evtdev, struct lpc32xx_clock_event_ddata, evtdev); /* - * Place timer in reset and program the delta in the prescale - * register (PR). When the prescale counter matches the value - * in PR the counter register is incremented and the compare - * match will trigger. After setup the timer is released from - * reset and enabled. + * Place timer in reset and program the delta in the match + * channel 0 (MR0). When the timer counter matches the value + * in MR0 register the match will trigger an interrupt. + * After setup the timer is released from reset and enabled. */ writel_relaxed(LPC32XX_TIMER_TCR_CRST, ddata->base + LPC32XX_TIMER_TCR); - writel_relaxed(delta, ddata->base + LPC32XX_TIMER_PR); + writel_relaxed(delta, ddata->base + LPC32XX_TIMER_MR0); writel_relaxed(LPC32XX_TIMER_TCR_CEN, ddata->base + LPC32XX_TIMER_TCR); return 0; @@ -86,11 +96,39 @@ static int lpc32xx_clkevt_shutdown(struct clock_event_device *evtdev) static int lpc32xx_clkevt_oneshot(struct clock_event_device *evtdev) { + struct lpc32xx_clock_event_ddata *ddata = + container_of(evtdev, struct lpc32xx_clock_event_ddata, evtdev); + /* * When using oneshot, we must also disable the timer * to wait for the first call to set_next_event(). */ - return lpc32xx_clkevt_shutdown(evtdev); + writel_relaxed(0, ddata->base + LPC32XX_TIMER_TCR); + + /* Enable interrupt, reset on match and stop on match (MCR). */ + writel_relaxed(LPC32XX_TIMER_MCR_MR0I | LPC32XX_TIMER_MCR_MR0R | + LPC32XX_TIMER_MCR_MR0S, ddata->base + LPC32XX_TIMER_MCR); + return 0; +} + +static int lpc32xx_clkevt_periodic(struct clock_event_device *evtdev) +{ + struct lpc32xx_clock_event_ddata *ddata = + container_of(evtdev, struct lpc32xx_clock_event_ddata, evtdev); + + /* Enable interrupt and reset on match. */ + writel_relaxed(LPC32XX_TIMER_MCR_MR0I | LPC32XX_TIMER_MCR_MR0R, + ddata->base + LPC32XX_TIMER_MCR); + + /* + * Place timer in reset and program the delta in the match + * channel 0 (MR0). + */ + writel_relaxed(LPC32XX_TIMER_TCR_CRST, ddata->base + LPC32XX_TIMER_TCR); + writel_relaxed(ddata->ticks_per_jiffy, ddata->base + LPC32XX_TIMER_MR0); + writel_relaxed(LPC32XX_TIMER_TCR_CEN, ddata->base + LPC32XX_TIMER_TCR); + + return 0; } static irqreturn_t lpc32xx_clock_event_handler(int irq, void *dev_id) @@ -108,11 +146,13 @@ static irqreturn_t lpc32xx_clock_event_handler(int irq, void *dev_id) static struct lpc32xx_clock_event_ddata lpc32xx_clk_event_ddata = { .evtdev = { .name = "lpc3220 clockevent", - .features = CLOCK_EVT_FEAT_ONESHOT, + .features = CLOCK_EVT_FEAT_ONESHOT | + CLOCK_EVT_FEAT_PERIODIC, .rating = 300, .set_next_event = lpc32xx_clkevt_next_event, .set_state_shutdown = lpc32xx_clkevt_shutdown, .set_state_oneshot = lpc32xx_clkevt_oneshot, + .set_state_periodic = lpc32xx_clkevt_periodic, }, }; @@ -162,6 +202,8 @@ static int __init lpc32xx_clocksource_init(struct device_node *np) } clocksource_timer_counter = base + LPC32XX_TIMER_TC; + lpc32xx_delay_timer.freq = rate; + register_current_timer_delay(&lpc32xx_delay_timer); sched_clock_register(lpc32xx_read_sched_clock, 32, rate); return 0; @@ -210,18 +252,16 @@ static int __init lpc32xx_clockevent_init(struct device_node *np) /* * Disable timer and clear any pending interrupt (IR) on match - * channel 0 (MR0). Configure a compare match value of 1 on MR0 - * and enable interrupt, reset on match and stop on match (MCR). + * channel 0 (MR0). Clear the prescaler as it's not used. */ writel_relaxed(0, base + LPC32XX_TIMER_TCR); + writel_relaxed(0, base + LPC32XX_TIMER_PR); writel_relaxed(0, base + LPC32XX_TIMER_CTCR); writel_relaxed(LPC32XX_TIMER_IR_MR0INT, base + LPC32XX_TIMER_IR); - writel_relaxed(1, base + LPC32XX_TIMER_MR0); - writel_relaxed(LPC32XX_TIMER_MCR_MR0I | LPC32XX_TIMER_MCR_MR0R | - LPC32XX_TIMER_MCR_MR0S, base + LPC32XX_TIMER_MCR); rate = clk_get_rate(clk); lpc32xx_clk_event_ddata.base = base; + lpc32xx_clk_event_ddata.ticks_per_jiffy = DIV_ROUND_CLOSEST(rate, HZ); clockevents_config_and_register(&lpc32xx_clk_event_ddata.evtdev, rate, 1, -1); 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 +#include +#include +#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 #include #include +#include #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/clockchips.h b/include/linux/clockchips.h index bdcf358dfce2..0d442e34c349 100644 --- a/include/linux/clockchips.h +++ b/include/linux/clockchips.h @@ -190,9 +190,9 @@ extern void clockevents_config_and_register(struct clock_event_device *dev, extern int clockevents_update_freq(struct clock_event_device *ce, u32 freq); static inline void -clockevents_calc_mult_shift(struct clock_event_device *ce, u32 freq, u32 minsec) +clockevents_calc_mult_shift(struct clock_event_device *ce, u32 freq, u32 maxsec) { - return clocks_calc_mult_shift(&ce->mult, &ce->shift, NSEC_PER_SEC, freq, minsec); + return clocks_calc_mult_shift(&ce->mult, &ce->shift, NSEC_PER_SEC, freq, maxsec); } extern void clockevents_suspend(void); diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h index 6013021a3b39..a307bf62974f 100644 --- a/include/linux/clocksource.h +++ b/include/linux/clocksource.h @@ -118,6 +118,23 @@ struct clocksource { /* simplify initialization of mask field */ #define CLOCKSOURCE_MASK(bits) (cycle_t)((bits) < 64 ? ((1ULL<<(bits))-1) : -1) +static inline u32 clocksource_freq2mult(u32 freq, u32 shift_constant, u64 from) +{ + /* freq = cyc/from + * mult/2^shift = ns/cyc + * mult = ns/cyc * 2^shift + * mult = from/freq * 2^shift + * mult = from * 2^shift / freq + * mult = (from<nsec = ts.tv_nsec; } +static inline void pps_get_ts(struct pps_event_time *ts) +{ + struct system_time_snapshot snap; + + ktime_get_snapshot(&snap); + ts->ts_real = ktime_to_timespec64(snap.real); #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); + ts->ts_raw = ktime_to_timespec64(snap.raw); +#endif } -#else /* CONFIG_NTP_PPS */ - -static inline void pps_get_ts(struct pps_event_time *ts) -{ - ktime_get_real_ts64(&ts->ts_real); -} - -#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 @@ -266,6 +266,64 @@ extern void timekeeping_inject_sleeptime64(struct timespec64 *delta); 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 */ 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/clocksource.c b/kernel/time/clocksource.c index 664de539299b..56ece145a814 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -323,13 +323,42 @@ static void clocksource_enqueue_watchdog(struct clocksource *cs) /* cs is a watchdog. */ if (cs->flags & CLOCK_SOURCE_IS_CONTINUOUS) cs->flags |= CLOCK_SOURCE_VALID_FOR_HRES; - /* Pick the best watchdog. */ - if (!watchdog || cs->rating > watchdog->rating) { - watchdog = cs; - /* Reset watchdog cycles */ - clocksource_reset_watchdog(); - } } + spin_unlock_irqrestore(&watchdog_lock, flags); +} + +static void clocksource_select_watchdog(bool fallback) +{ + struct clocksource *cs, *old_wd; + unsigned long flags; + + spin_lock_irqsave(&watchdog_lock, flags); + /* save current watchdog */ + old_wd = watchdog; + if (fallback) + watchdog = NULL; + + list_for_each_entry(cs, &clocksource_list, list) { + /* cs is a clocksource to be watched. */ + if (cs->flags & CLOCK_SOURCE_MUST_VERIFY) + continue; + + /* Skip current if we were requested for a fallback. */ + if (fallback && cs == old_wd) + continue; + + /* Pick the best watchdog. */ + if (!watchdog || cs->rating > watchdog->rating) + watchdog = cs; + } + /* If we failed to find a fallback restore the old one. */ + if (!watchdog) + watchdog = old_wd; + + /* If we changed the watchdog we need to reset cycles. */ + if (watchdog != old_wd) + clocksource_reset_watchdog(); + /* Check if the watchdog timer needs to be started. */ clocksource_start_watchdog(); spin_unlock_irqrestore(&watchdog_lock, flags); @@ -404,6 +433,7 @@ static void clocksource_enqueue_watchdog(struct clocksource *cs) cs->flags |= CLOCK_SOURCE_VALID_FOR_HRES; } +static void clocksource_select_watchdog(bool fallback) { } static inline void clocksource_dequeue_watchdog(struct clocksource *cs) { } static inline void clocksource_resume_watchdog(void) { } static inline int __clocksource_watchdog_kthread(void) { return 0; } @@ -736,6 +766,7 @@ int __clocksource_register_scale(struct clocksource *cs, u32 scale, u32 freq) clocksource_enqueue(cs); clocksource_enqueue_watchdog(cs); clocksource_select(); + clocksource_select_watchdog(false); mutex_unlock(&clocksource_mutex); return 0; } @@ -758,6 +789,7 @@ void clocksource_change_rating(struct clocksource *cs, int rating) mutex_lock(&clocksource_mutex); __clocksource_change_rating(cs, rating); clocksource_select(); + clocksource_select_watchdog(false); mutex_unlock(&clocksource_mutex); } EXPORT_SYMBOL(clocksource_change_rating); @@ -767,12 +799,12 @@ EXPORT_SYMBOL(clocksource_change_rating); */ static int clocksource_unbind(struct clocksource *cs) { - /* - * I really can't convince myself to support this on hardware - * designed by lobotomized monkeys. - */ - if (clocksource_is_watchdog(cs)) - return -EBUSY; + if (clocksource_is_watchdog(cs)) { + /* Select and try to install a replacement watchdog. */ + clocksource_select_watchdog(true); + if (clocksource_is_watchdog(cs)) + return -EBUSY; + } if (cs == curr_clocksource) { /* Select and try to install a replacement clock source */ diff --git a/kernel/time/jiffies.c b/kernel/time/jiffies.c index 347fecf86a3f..555e21f7b966 100644 --- a/kernel/time/jiffies.c +++ b/kernel/time/jiffies.c @@ -68,7 +68,7 @@ static struct clocksource clocksource_jiffies = { .name = "jiffies", .rating = 1, /* lowest valid rating*/ .read = jiffies_read, - .mask = 0xffffffff, /*32bits*/ + .mask = CLOCKSOURCE_MASK(32), .mult = NSEC_PER_JIFFY << JIFFIES_SHIFT, /* details above */ .shift = JIFFIES_SHIFT, .max_cycles = 10, diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 34b4cedfa80d..9c629bbed572 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; @@ -298,19 +299,36 @@ u32 (*arch_gettimeoffset)(void) = default_arch_gettimeoffset; static inline u32 arch_gettimeoffset(void) { return 0; } #endif -static inline s64 timekeeping_get_ns(struct tk_read_base *tkr) +static inline s64 timekeeping_delta_to_ns(struct tk_read_base *tkr, + cycle_t delta) { - cycle_t delta; s64 nsec; - delta = timekeeping_get_delta(tkr); - - nsec = (delta * tkr->mult + tkr->xtime_nsec) >> tkr->shift; + 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; + + delta = timekeeping_get_delta(tkr); + return timekeeping_delta_to_ns(tkr, delta); +} + +static inline s64 timekeeping_cycles_to_ns(struct tk_read_base *tkr, + cycle_t cycles) +{ + cycle_t delta; + + /* 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); +} + /** * update_fast_timekeeper - Update the fast and NMI safe monotonic timekeeper. * @tkr: Timekeeping readout base from which we take the update @@ -857,44 +875,262 @@ time64_t __ktime_get_real_seconds(void) return tk->xtime_sec; } - -#ifdef CONFIG_NTP_PPS - /** - * 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 - * - * 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. + * ktime_get_snapshot - snapshots the realtime/monotonic raw clocks with counter + * @systime_snapshot: pointer to struct receiving the system time snapshot */ -void ktime_get_raw_and_real_ts64(struct timespec64 *ts_raw, struct timespec64 *ts_real) +void ktime_get_snapshot(struct system_time_snapshot *systime_snapshot) { struct timekeeper *tk = &tk_core.timekeeper; unsigned long seq; - s64 nsecs_raw, nsecs_real; + ktime_t base_raw; + ktime_t base_real; + s64 nsec_raw; + s64 nsec_real; + cycle_t now; WARN_ON_ONCE(timekeeping_suspended); do { seq = read_seqcount_begin(&tk_core.seq); - *ts_raw = tk->raw_time; - ts_real->tv_sec = tk->xtime_sec; - ts_real->tv_nsec = 0; - - nsecs_raw = timekeeping_get_ns(&tk->tkr_raw); - nsecs_real = timekeeping_get_ns(&tk->tkr_mono); - + 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)); - timespec64_add_ns(ts_raw, nsecs_raw); - timespec64_add_ns(ts_real, nsecs_real); + 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(ktime_get_raw_and_real_ts64); +EXPORT_SYMBOL_GPL(ktime_get_snapshot); -#endif /* CONFIG_NTP_PPS */ +/* 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; +} + +/** + * 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 + * + * 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. + */ +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; + u64 corr_raw, corr_real; + bool interp_forward; + int ret; + + 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 = 0; + 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; + + /* + * 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; + } + + 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)); + + xtstamp->sys_realtime = ktime_add_ns(base_real, nsec_real); + xtstamp->sys_monoraw = ktime_add_ns(base_raw, nsec_raw); + + /* + * 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