X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/de355530ae67247cbd0da700edb3a2a1dae884c2..c18c124eaa464aaaa5549e99e5a70fc9cbb50944:/osfmk/i386/rtclock.c diff --git a/osfmk/i386/rtclock.c b/osfmk/i386/rtclock.c index 3a995311d..d0a2ed840 100644 --- a/osfmk/i386/rtclock.c +++ b/osfmk/i386/rtclock.c @@ -1,23 +1,29 @@ /* - * Copyright (c) 2000 Apple Computer, Inc. All rights reserved. + * Copyright (c) 2000-2012 Apple Inc. All rights reserved. * - * @APPLE_LICENSE_HEADER_START@ + * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ * - * The contents of this file constitute Original Code as defined in and - * are subject to the Apple Public Source License Version 1.1 (the - * "License"). You may not use this file except in compliance with the - * License. Please obtain a copy of the License at - * http://www.apple.com/publicsource and read it before using this file. + * This file contains Original Code and/or Modifications of Original Code + * as defined in and that are subject to the Apple Public Source License + * Version 2.0 (the 'License'). You may not use this file except in + * compliance with the License. The rights granted to you under the License + * may not be used to create, or enable the creation or redistribution of, + * unlawful or unlicensed copies of an Apple operating system, or to + * circumvent, violate, or enable the circumvention or violation of, any + * terms of an Apple operating system software license agreement. * - * This Original Code and all software distributed under the License are - * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER + * Please obtain a copy of the License at + * http://www.opensource.apple.com/apsl/ and read it before using this file. + * + * The Original Code and all software distributed under the License are + * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, - * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the - * License for the specific language governing rights and limitations - * under the License. + * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. + * Please see the License for the specific language governing rights and + * limitations under the License. * - * @APPLE_LICENSE_HEADER_END@ + * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ /* * @OSF_COPYRIGHT@ @@ -26,1001 +32,490 @@ /* * File: i386/rtclock.c * Purpose: Routines for handling the machine dependent - * real-time clock. This clock is generated by - * the Intel 8254 Programmable Interval Timer. + * real-time clock. Historically, this clock is + * generated by the Intel 8254 Programmable Interval + * Timer, but local apic timers are now used for + * this purpose with the master time reference being + * the cpu clock counted by the timestamp MSR. */ -#include -#include -#include -#include -#include + +#include + #include +#include #include +#include #include #include #include -#include /* HZ */ +#include +#include #include #include #include /* for kernel_map */ -#include -#include -#include +#include +#include +#include +#include +#include +#include +#include +#include #include -#include -#include - -int sysclk_config(void); - -int sysclk_init(void); +#include +#include +#include +#include +#include +#include +#define UI_CPUFREQ_ROUNDING_FACTOR 10000000 -kern_return_t sysclk_gettime( - mach_timespec_t *cur_time); +int rtclock_init(void); -kern_return_t sysclk_getattr( - clock_flavor_t flavor, - clock_attr_t attr, - mach_msg_type_number_t *count); +uint64_t tsc_rebase_abs_time = 0; -kern_return_t sysclk_setattr( - clock_flavor_t flavor, - clock_attr_t attr, - mach_msg_type_number_t count); +static void rtc_set_timescale(uint64_t cycles); +static uint64_t rtc_export_speed(uint64_t cycles); -void sysclk_setalarm( - mach_timespec_t *alarm_time); - -extern void (*IOKitRegisterInterruptHook)(void *, int irq, int isclock); - -/* - * Inlines to get timestamp counter value. - */ - -static inline void rdtsc_hilo(uint32_t *hi, uint32_t *lo) { - asm volatile("rdtsc": "=a" (*lo), "=d" (*hi)); +void +rtc_timer_start(void) +{ + /* + * Force a complete re-evaluation of timer deadlines. + */ + x86_lcpu()->rtcDeadline = EndOfAllTime; + timer_resync_deadlines(); } -static inline uint64_t rdtsc_64(void) { - uint64_t result; - asm volatile("rdtsc": "=A" (result)); - return result; +static inline uint32_t +_absolutetime_to_microtime(uint64_t abstime, clock_sec_t *secs, clock_usec_t *microsecs) +{ + uint32_t remain; + *secs = abstime / (uint64_t)NSEC_PER_SEC; + remain = (uint32_t)(abstime % (uint64_t)NSEC_PER_SEC); + *microsecs = remain / NSEC_PER_USEC; + return remain; } -/* - * Lists of clock routines. - */ -struct clock_ops sysclk_ops = { - sysclk_config, sysclk_init, - sysclk_gettime, 0, - sysclk_getattr, sysclk_setattr, - sysclk_setalarm, -}; - -int calend_config(void); - -int calend_init(void); - -kern_return_t calend_gettime( - mach_timespec_t *cur_time); - -kern_return_t calend_settime( - mach_timespec_t *cur_time); - -kern_return_t calend_getattr( - clock_flavor_t flavor, - clock_attr_t attr, - mach_msg_type_number_t *count); - -struct clock_ops calend_ops = { - calend_config, calend_init, - calend_gettime, calend_settime, - calend_getattr, 0, - 0, -}; - -/* local data declarations */ -mach_timespec_t *RtcTime = (mach_timespec_t *)0; -mach_timespec_t *RtcAlrm; -clock_res_t RtcDelt; - -/* global data declarations */ -struct { - uint64_t abstime; - - mach_timespec_t time; - mach_timespec_t alarm_time; /* time of next alarm */ - - mach_timespec_t calend_offset; - boolean_t calend_is_set; - - uint64_t timer_deadline; - boolean_t timer_is_set; - clock_timer_func_t timer_expire; - - clock_res_t new_ires; /* pending new resolution (nano ) */ - clock_res_t intr_nsec; /* interrupt resolution (nano) */ - - decl_simple_lock_data(,lock) /* real-time clock device lock */ -} rtclock; - -unsigned int clknum; /* clks per second */ -unsigned int new_clknum; /* pending clknum */ -unsigned int time_per_clk; /* time per clk in ZHZ */ -unsigned int clks_per_int; /* clks per interrupt */ -unsigned int clks_per_int_99; -int rtc_intr_count; /* interrupt counter */ -int rtc_intr_hertz; /* interrupts per HZ */ -int rtc_intr_freq; /* interrupt frequency */ -int rtc_print_lost_tick; /* print lost tick */ - -uint32_t rtc_cyc_per_sec; /* processor cycles per seconds */ -uint32_t rtc_last_int_tsc_lo; /* tsc values saved per interupt */ -uint32_t rtc_last_int_tsc_hi; - -/* - * Macros to lock/unlock real-time clock device. - */ -#define LOCK_RTC(s) \ -MACRO_BEGIN \ - (s) = splclock(); \ - simple_lock(&rtclock.lock); \ -MACRO_END - -#define UNLOCK_RTC(s) \ -MACRO_BEGIN \ - simple_unlock(&rtclock.lock); \ - splx(s); \ -MACRO_END +static inline void +_absolutetime_to_nanotime(uint64_t abstime, clock_sec_t *secs, clock_usec_t *nanosecs) +{ + *secs = abstime / (uint64_t)NSEC_PER_SEC; + *nanosecs = (clock_usec_t)(abstime % (uint64_t)NSEC_PER_SEC); +} /* - * i8254 control. ** MONUMENT ** - * - * The i8254 is a traditional PC device with some arbitrary characteristics. - * Basically, it is a register that counts at a fixed rate and can be - * programmed to generate an interrupt every N counts. The count rate is - * clknum counts per second (see pit.h), historically 1193167 we believe. - * Various constants are computed based on this value, and we calculate - * them at init time for execution efficiency. To obtain sufficient - * accuracy, some of the calculation are most easily done in floating - * point and then converted to int. + * Nanotime/mach_absolutime_time + * ----------------------------- + * The timestamp counter (TSC) - which counts cpu clock cycles and can be read + * efficiently by the kernel and in userspace - is the reference for all timing. + * The cpu clock rate is platform-dependent and may stop or be reset when the + * processor is napped/slept. As a result, nanotime is the software abstraction + * used to maintain a monotonic clock, adjusted from an outside reference as needed. * - * We want an interrupt every 10 milliseconds, approximately. The count - * which will do that is clks_per_int. However, that many counts is not - * *exactly* 10 milliseconds; it is a bit more or less depending on - * roundoff. The actual time per tick is calculated and saved in - * rtclock.intr_nsec, and it is that value which is added to the time - * register on each tick. + * The kernel maintains nanotime information recording: + * - the ratio of tsc to nanoseconds + * with this ratio expressed as a 32-bit scale and shift + * (power of 2 divider); + * - { tsc_base, ns_base } pair of corresponding timestamps. * - * The i8254 counter can be read between interrupts in order to determine - * the time more accurately. The counter counts down from the preset value - * toward 0, and we have to handle the case where the counter has been - * reset just before being read and before the interrupt has been serviced. - * Given a count since the last interrupt, the time since then is given - * by (count * time_per_clk). In order to minimize integer truncation, - * we perform this calculation in an arbitrary unit of time which maintains - * the maximum precision, i.e. such that one tick is 1.0e9 of these units, - * or close to the precision of a 32-bit int. We then divide by this unit - * (which doesn't lose precision) to get nanoseconds. For notation - * purposes, this unit is defined as ZHZ = zanoseconds per nanosecond. + * The tuple {tsc_base, ns_base, scale, shift} is exported in the commpage + * for the userspace nanotime routine to read. * - * This sequence to do all this is in sysclk_gettime. For efficiency, this - * sequence also needs the value that the counter will have if it has just - * overflowed, so we precompute that also. ALSO, certain platforms - * (specifically the DEC XL5100) have been observed to have problem - * with latching the counter, and they occasionally (say, one out of - * 100,000 times) return a bogus value. Hence, the present code reads - * the counter twice and checks for a consistent pair of values. - * - * Some attributes of the rt clock can be changed, including the - * interrupt resolution. We default to the minimum resolution (10 ms), - * but allow a finer resolution to be requested. The assumed frequency - * of the clock can also be set since it appears that the actual - * frequency of real-world hardware can vary from the nominal by - * 200 ppm or more. When the frequency is set, the values above are - * recomputed and we continue without resetting or changing anything else. + * All of the routines which update the nanotime data are non-reentrant. This must + * be guaranteed by the caller. */ -#define RTC_MINRES (NSEC_PER_SEC / HZ) /* nsec per tick */ -#define RTC_MAXRES (RTC_MINRES / 20) /* nsec per tick */ -#define ZANO (1000000000) -#define ZHZ (ZANO / (NSEC_PER_SEC / HZ)) -#define READ_8254(val) { \ - outb(PITCTL_PORT, PIT_C0); \ - (val) = inb(PITCTR0_PORT); \ - (val) |= inb(PITCTR0_PORT) << 8 ; } - -/* - * Calibration delay counts. - */ -unsigned int delaycount = 100; -unsigned int microdata = 50; +static inline void +rtc_nanotime_set_commpage(pal_rtc_nanotime_t *rntp) +{ + commpage_set_nanotime(rntp->tsc_base, rntp->ns_base, rntp->scale, rntp->shift); +} /* - * Forward decl. + * rtc_nanotime_init: + * + * Intialize the nanotime info from the base time. */ +static inline void +_rtc_nanotime_init(pal_rtc_nanotime_t *rntp, uint64_t base) +{ + uint64_t tsc = rdtsc64(); -extern int measure_delay(int us); -void rtc_setvals( unsigned int, clock_res_t ); + _pal_rtc_nanotime_store(tsc, base, rntp->scale, rntp->shift, rntp); +} -static void rtc_set_cyc_per_sec(); +static void +rtc_nanotime_init(uint64_t base) +{ + _rtc_nanotime_init(&pal_rtc_nanotime_info, base); + rtc_nanotime_set_commpage(&pal_rtc_nanotime_info); +} /* - * Initialize non-zero clock structure values. + * rtc_nanotime_init_commpage: + * + * Call back from the commpage initialization to + * cause the commpage data to be filled in once the + * commpages have been created. */ void -rtc_setvals( - unsigned int new_clknum, - clock_res_t new_ires - ) +rtc_nanotime_init_commpage(void) { - unsigned int timeperclk; - unsigned int scale0; - unsigned int scale1; - unsigned int res; - - clknum = new_clknum; - rtc_intr_freq = (NSEC_PER_SEC / new_ires); - rtc_intr_hertz = rtc_intr_freq / HZ; - clks_per_int = (clknum + (rtc_intr_freq / 2)) / rtc_intr_freq; - clks_per_int_99 = clks_per_int - clks_per_int/100; - - /* - * The following calculations are done with scaling integer operations - * in order that the integer results are accurate to the lsb. - */ - timeperclk = div_scale(ZANO, clknum, &scale0); /* 838.105647 nsec */ - - time_per_clk = mul_scale(ZHZ, timeperclk, &scale1); /* 83810 */ - if (scale0 > scale1) - time_per_clk >>= (scale0 - scale1); - else if (scale0 < scale1) - panic("rtc_clock: time_per_clk overflow\n"); - - /* - * Notice that rtclock.intr_nsec is signed ==> use unsigned int res - */ - res = mul_scale(clks_per_int, timeperclk, &scale1); /* 10000276 */ - if (scale0 > scale1) - rtclock.intr_nsec = res >> (scale0 - scale1); - else - panic("rtc_clock: rtclock.intr_nsec overflow\n"); - - rtc_intr_count = 1; - RtcDelt = rtclock.intr_nsec/2; + spl_t s = splclock(); + + rtc_nanotime_set_commpage(&pal_rtc_nanotime_info); + splx(s); } /* - * Configure the real-time clock device. Return success (1) - * or failure (0). + * rtc_nanotime_read: + * + * Returns the current nanotime value, accessable from any + * context. */ - -int -sysclk_config(void) +static inline uint64_t +rtc_nanotime_read(void) { - int RtcFlag; - int pic; - -#if NCPUS > 1 - mp_disable_preemption(); - if (cpu_number() != master_cpu) { - mp_enable_preemption(); - return(1); - } - mp_enable_preemption(); -#endif - /* - * Setup device. - */ -#if MP_V1_1 - { - extern boolean_t mp_v1_1_initialized; - if (mp_v1_1_initialized) - pic = 2; - else - pic = 0; - } -#else - pic = 0; /* FIXME .. interrupt registration moved to AppleIntelClock */ -#endif - - - /* - * We should attempt to test the real-time clock - * device here. If it were to fail, we should panic - * the system. - */ - RtcFlag = /* test device */1; - printf("realtime clock configured\n"); - - simple_lock_init(&rtclock.lock, ETAP_NO_TRACE); - return (RtcFlag); + return _rtc_nanotime_read(&pal_rtc_nanotime_info); } /* - * Initialize the real-time clock device. Return success (1) - * or failure (0). Since the real-time clock is required to - * provide canonical mapped time, we allocate a page to keep - * the clock time value. In addition, various variables used - * to support the clock are initialized. Note: the clock is - * not started until rtclock_reset is called. + * rtc_clock_napped: + * + * Invoked from power management when we exit from a low C-State (>= C4) + * and the TSC has stopped counting. The nanotime data is updated according + * to the provided value which represents the new value for nanotime. */ -int -sysclk_init(void) -{ - vm_offset_t *vp; -#if NCPUS > 1 - mp_disable_preemption(); - if (cpu_number() != master_cpu) { - mp_enable_preemption(); - return(1); +void +rtc_clock_napped(uint64_t base, uint64_t tsc_base) +{ + pal_rtc_nanotime_t *rntp = &pal_rtc_nanotime_info; + uint64_t oldnsecs; + uint64_t newnsecs; + uint64_t tsc; + + assert(!ml_get_interrupts_enabled()); + tsc = rdtsc64(); + oldnsecs = rntp->ns_base + _rtc_tsc_to_nanoseconds(tsc - rntp->tsc_base, rntp); + newnsecs = base + _rtc_tsc_to_nanoseconds(tsc - tsc_base, rntp); + + /* + * Only update the base values if time using the new base values + * is later than the time using the old base values. + */ + if (oldnsecs < newnsecs) { + _pal_rtc_nanotime_store(tsc_base, base, rntp->scale, rntp->shift, rntp); + rtc_nanotime_set_commpage(rntp); } - mp_enable_preemption(); -#endif - - RtcTime = &rtclock.time; - rtc_setvals( CLKNUM, RTC_MINRES ); /* compute constants */ - rtc_set_cyc_per_sec(); /* compute number of tsc beats per second */ - return (1); } -static volatile unsigned int last_ival = 0; - /* - * Get the clock device time. This routine is responsible - * for converting the device's machine dependent time value - * into a canonical mach_timespec_t value. + * Invoked from power management to correct the SFLM TSC entry drift problem: + * a small delta is added to the tsc_base. This is equivalent to nudgin time + * backwards. We require this to be on the order of a TSC quantum which won't + * cause callers of mach_absolute_time() to see time going backwards! */ -kern_return_t -sysclk_gettime( - mach_timespec_t *cur_time) /* OUT */ +void +rtc_clock_adjust(uint64_t tsc_base_delta) { - mach_timespec_t itime = {0, 0}; - unsigned int val, val2; - int s; - - if (!RtcTime) { - /* Uninitialized */ - cur_time->tv_nsec = 0; - cur_time->tv_sec = 0; - return (KERN_SUCCESS); - } + pal_rtc_nanotime_t *rntp = &pal_rtc_nanotime_info; - /* - * Inhibit interrupts. Determine the incremental - * time since the last interrupt. (This could be - * done in assembler for a bit more speed). - */ - LOCK_RTC(s); - do { - READ_8254(val); /* read clock */ - READ_8254(val2); /* read clock */ - } while ( val2 > val || val2 < val - 10 ); - if ( val > clks_per_int_99 ) { - outb( 0x0a, 0x20 ); /* see if interrupt pending */ - if ( inb( 0x20 ) & 1 ) - itime.tv_nsec = rtclock.intr_nsec; /* yes, add a tick */ - } - itime.tv_nsec += ((clks_per_int - val) * time_per_clk) / ZHZ; - if ( itime.tv_nsec < last_ival ) { - if (rtc_print_lost_tick) - printf( "rtclock: missed clock interrupt.\n" ); - } - last_ival = itime.tv_nsec; - cur_time->tv_sec = rtclock.time.tv_sec; - cur_time->tv_nsec = rtclock.time.tv_nsec; - UNLOCK_RTC(s); - ADD_MACH_TIMESPEC(cur_time, ((mach_timespec_t *)&itime)); - return (KERN_SUCCESS); + assert(!ml_get_interrupts_enabled()); + assert(tsc_base_delta < 100ULL); /* i.e. it's small */ + _rtc_nanotime_adjust(tsc_base_delta, rntp); + rtc_nanotime_set_commpage(rntp); } -kern_return_t -sysclk_gettime_internal( - mach_timespec_t *cur_time) /* OUT */ +void +rtc_clock_stepping(__unused uint32_t new_frequency, + __unused uint32_t old_frequency) { - mach_timespec_t itime = {0, 0}; - unsigned int val, val2; - - if (!RtcTime) { - /* Uninitialized */ - cur_time->tv_nsec = 0; - cur_time->tv_sec = 0; - return (KERN_SUCCESS); - } + panic("rtc_clock_stepping unsupported"); +} - /* - * Inhibit interrupts. Determine the incremental - * time since the last interrupt. (This could be - * done in assembler for a bit more speed). - */ - do { - READ_8254(val); /* read clock */ - READ_8254(val2); /* read clock */ - } while ( val2 > val || val2 < val - 10 ); - if ( val > clks_per_int_99 ) { - outb( 0x0a, 0x20 ); /* see if interrupt pending */ - if ( inb( 0x20 ) & 1 ) - itime.tv_nsec = rtclock.intr_nsec; /* yes, add a tick */ - } - itime.tv_nsec += ((clks_per_int - val) * time_per_clk) / ZHZ; - if ( itime.tv_nsec < last_ival ) { - if (rtc_print_lost_tick) - printf( "rtclock: missed clock interrupt.\n" ); - } - last_ival = itime.tv_nsec; - cur_time->tv_sec = rtclock.time.tv_sec; - cur_time->tv_nsec = rtclock.time.tv_nsec; - ADD_MACH_TIMESPEC(cur_time, ((mach_timespec_t *)&itime)); - return (KERN_SUCCESS); +void +rtc_clock_stepped(__unused uint32_t new_frequency, + __unused uint32_t old_frequency) +{ + panic("rtc_clock_stepped unsupported"); } /* - * Get the clock device time when ALL interrupts are already disabled. - * Same as above except for turning interrupts off and on. - * This routine is responsible for converting the device's machine dependent - * time value into a canonical mach_timespec_t value. + * rtc_sleep_wakeup: + * + * Invoked from power management when we have awoken from a sleep (S3) + * and the TSC has been reset, or from Deep Idle (S0) sleep when the TSC + * has progressed. The nanotime data is updated based on the passed-in value. + * + * The caller must guarantee non-reentrancy. */ void -sysclk_gettime_interrupts_disabled( - mach_timespec_t *cur_time) /* OUT */ +rtc_sleep_wakeup( + uint64_t base) { - mach_timespec_t itime = {0, 0}; - unsigned int val; - - if (!RtcTime) { - /* Uninitialized */ - cur_time->tv_nsec = 0; - cur_time->tv_sec = 0; - return; - } - - simple_lock(&rtclock.lock); + /* Set fixed configuration for lapic timers */ + rtc_timer->rtc_config(); /* - * Copy the current time knowing that we cant be interrupted - * between the two longwords and so dont need to use MTS_TO_TS + * Reset nanotime. + * The timestamp counter will have been reset + * but nanotime (uptime) marches onward. */ - READ_8254(val); /* read clock */ - if ( val > clks_per_int_99 ) { - outb( 0x0a, 0x20 ); /* see if interrupt pending */ - if ( inb( 0x20 ) & 1 ) - itime.tv_nsec = rtclock.intr_nsec; /* yes, add a tick */ - } - itime.tv_nsec += ((clks_per_int - val) * time_per_clk) / ZHZ; - if ( itime.tv_nsec < last_ival ) { - if (rtc_print_lost_tick) - printf( "rtclock: missed clock interrupt.\n" ); - } - last_ival = itime.tv_nsec; - cur_time->tv_sec = rtclock.time.tv_sec; - cur_time->tv_nsec = rtclock.time.tv_nsec; - ADD_MACH_TIMESPEC(cur_time, ((mach_timespec_t *)&itime)); - - simple_unlock(&rtclock.lock); -} - -// utility routine -// Code to calculate how many processor cycles are in a second... - -static void -rtc_set_cyc_per_sec() -{ - - int x, y; - uint64_t cycles; - uint32_t c[15]; // array for holding sampled cycle counts - mach_timespec_t tst[15]; // array for holding time values. NOTE for some reason tv_sec not work - - for (x=0; x<15; x++) { // quick sample 15 times - tst[x].tv_sec = 0; - tst[x].tv_nsec = 0; - sysclk_gettime_internal(&tst[x]); - rdtsc_hilo(&y, &c[x]); - } - y = 0; - cycles = 0; - for (x=0; x<14; x++) { - // simple formula really. calculate the numerator as the number of elapsed processor - // cycles * 1000 to adjust for the resolution we want. The denominator is the - // elapsed "real" time in nano-seconds. The result will be the processor speed in - // Mhz. any overflows will be discarded before they are added - if ((c[x+1] > c[x]) && (tst[x+1].tv_nsec > tst[x].tv_nsec)) { - cycles += ((uint64_t)(c[x+1]-c[x]) * NSEC_PER_SEC ) / (uint64_t)(tst[x+1].tv_nsec - tst[x].tv_nsec); // elapsed nsecs - y +=1; - } - } - if (y>0) { // we got more than 1 valid sample. This also takes care of the case of if the clock isn't running - cycles = cycles / y; // calc our average - } - rtc_cyc_per_sec = cycles; - rdtsc_hilo(&rtc_last_int_tsc_hi, &rtc_last_int_tsc_lo); + rtc_nanotime_init(base); } -static -natural_t -get_uptime_cycles(void) -{ - // get the time since the last interupt based on the processors TSC ignoring the - // RTC for speed - - uint32_t a,d,intermediate_lo,intermediate_hi,result; - uint64_t newTime; - - rdtsc_hilo(&d, &a); - if (d != rtc_last_int_tsc_hi) { - newTime = d-rtc_last_int_tsc_hi; - newTime = (newTime<<32) + (a-rtc_last_int_tsc_lo); - result = newTime; - } else { - result = a-rtc_last_int_tsc_lo; - } - __asm__ volatile ( " mul %3 ": "=eax" (intermediate_lo), "=edx" (intermediate_hi): "a"(result), "d"(NSEC_PER_SEC) ); - __asm__ volatile ( " div %3": "=eax" (result): "eax"(intermediate_lo), "edx" (intermediate_hi), "ecx" (rtc_cyc_per_sec) ); - return result; -} - - /* - * Get clock device attributes. + * rtclock_early_init() is called very early at boot to + * establish mach_absolute_time() and set it to zero. */ -kern_return_t -sysclk_getattr( - clock_flavor_t flavor, - clock_attr_t attr, /* OUT */ - mach_msg_type_number_t *count) /* IN/OUT */ +void +rtclock_early_init(void) { - spl_t s; - - if (*count != 1) - return (KERN_FAILURE); - switch (flavor) { - - case CLOCK_GET_TIME_RES: /* >0 res */ -#if (NCPUS == 1 || (MP_V1_1 && 0)) - LOCK_RTC(s); - *(clock_res_t *) attr = 1000; - UNLOCK_RTC(s); - break; -#endif /* (NCPUS == 1 || (MP_V1_1 && 0)) && AT386 */ - case CLOCK_ALARM_CURRES: /* =0 no alarm */ - LOCK_RTC(s); - *(clock_res_t *) attr = rtclock.intr_nsec; - UNLOCK_RTC(s); - break; - - case CLOCK_ALARM_MAXRES: - *(clock_res_t *) attr = RTC_MAXRES; - break; - - case CLOCK_ALARM_MINRES: - *(clock_res_t *) attr = RTC_MINRES; - break; - - default: - return (KERN_INVALID_VALUE); - } - return (KERN_SUCCESS); + assert(tscFreq); + rtc_set_timescale(tscFreq); } /* - * Set clock device attributes. + * Initialize the real-time clock device. + * In addition, various variables used to support the clock are initialized. */ -kern_return_t -sysclk_setattr( - clock_flavor_t flavor, - clock_attr_t attr, /* IN */ - mach_msg_type_number_t count) /* IN */ +int +rtclock_init(void) { - spl_t s; - int freq; - int adj; - clock_res_t new_ires; + uint64_t cycles; - if (count != 1) - return (KERN_FAILURE); - switch (flavor) { + assert(!ml_get_interrupts_enabled()); - case CLOCK_GET_TIME_RES: - case CLOCK_ALARM_MAXRES: - case CLOCK_ALARM_MINRES: - return (KERN_FAILURE); + if (cpu_number() == master_cpu) { - case CLOCK_ALARM_CURRES: - new_ires = *(clock_res_t *) attr; + assert(tscFreq); /* - * The new resolution must be within the predetermined - * range. If the desired resolution cannot be achieved - * to within 0.1%, an error is returned. + * Adjust and set the exported cpu speed. */ - if (new_ires < RTC_MAXRES || new_ires > RTC_MINRES) - return (KERN_INVALID_VALUE); - freq = (NSEC_PER_SEC / new_ires); - adj = (((clknum % freq) * new_ires) / clknum); - if (adj > (new_ires / 1000)) - return (KERN_INVALID_VALUE); + cycles = rtc_export_speed(tscFreq); + /* - * Record the new alarm resolution which will take effect - * on the next HZ aligned clock tick. + * Set min/max to actual. + * ACPI may update these later if speed-stepping is detected. */ - LOCK_RTC(s); - if ( freq != rtc_intr_freq ) { - rtclock.new_ires = new_ires; - new_clknum = clknum; - } - UNLOCK_RTC(s); - return (KERN_SUCCESS); - - default: - return (KERN_INVALID_VALUE); - } -} - -/* - * Set next alarm time for the clock device. This call - * always resets the time to deliver an alarm for the - * clock. - */ -void -sysclk_setalarm( - mach_timespec_t *alarm_time) -{ - spl_t s; + gPEClockFrequencyInfo.cpu_frequency_min_hz = cycles; + gPEClockFrequencyInfo.cpu_frequency_max_hz = cycles; - LOCK_RTC(s); - rtclock.alarm_time = *alarm_time; - RtcAlrm = &rtclock.alarm_time; - UNLOCK_RTC(s); -} + rtc_timer_init(); + clock_timebase_init(); + ml_init_lock_timeout(); + ml_init_delay_spin_threshold(10); + } -/* - * Configure the calendar clock. - */ -int -calend_config(void) -{ - return bbc_config(); -} + /* Set fixed configuration for lapic timers */ + rtc_timer->rtc_config(); + rtc_timer_start(); -/* - * Initialize calendar clock. - */ -int -calend_init(void) -{ return (1); } -/* - * Get the current clock time. - */ -kern_return_t -calend_gettime( - mach_timespec_t *cur_time) /* OUT */ -{ - spl_t s; +// utility routine +// Code to calculate how many processor cycles are in a second... - LOCK_RTC(s); - if (!rtclock.calend_is_set) { - UNLOCK_RTC(s); - return (KERN_FAILURE); +static void +rtc_set_timescale(uint64_t cycles) +{ + pal_rtc_nanotime_t *rntp = &pal_rtc_nanotime_info; + uint32_t shift = 0; + + /* the "scale" factor will overflow unless cycles>SLOW_TSC_THRESHOLD */ + + while ( cycles <= SLOW_TSC_THRESHOLD) { + shift++; + cycles <<= 1; } + + rntp->scale = (uint32_t)(((uint64_t)NSEC_PER_SEC << 32) / cycles); - (void) sysclk_gettime_internal(cur_time); - ADD_MACH_TIMESPEC(cur_time, &rtclock.calend_offset); - UNLOCK_RTC(s); + rntp->shift = shift; + + /* + * On some platforms, the TSC is not reset at warm boot. But the + * rebase time must be relative to the current boot so we can't use + * mach_absolute_time(). Instead, we convert the TSC delta since boot + * to nanoseconds. + */ + if (tsc_rebase_abs_time == 0) + tsc_rebase_abs_time = _rtc_tsc_to_nanoseconds( + rdtsc64() - tsc_at_boot, rntp); - return (KERN_SUCCESS); + rtc_nanotime_init(0); } -/* - * Set the current clock time. - */ -kern_return_t -calend_settime( - mach_timespec_t *new_time) +static uint64_t +rtc_export_speed(uint64_t cyc_per_sec) { - mach_timespec_t curr_time; - spl_t s; + pal_rtc_nanotime_t *rntp = &pal_rtc_nanotime_info; + uint64_t cycles; - LOCK_RTC(s); - (void) sysclk_gettime_internal(&curr_time); - rtclock.calend_offset = *new_time; - SUB_MACH_TIMESPEC(&rtclock.calend_offset, &curr_time); - rtclock.calend_is_set = TRUE; - UNLOCK_RTC(s); + if (rntp->shift != 0 ) + printf("Slow TSC, rtc_nanotime.shift == %d\n", rntp->shift); + + /* Round: */ + cycles = ((cyc_per_sec + (UI_CPUFREQ_ROUNDING_FACTOR/2)) + / UI_CPUFREQ_ROUNDING_FACTOR) + * UI_CPUFREQ_ROUNDING_FACTOR; - (void) bbc_settime(new_time); + /* + * Set current measured speed. + */ + if (cycles >= 0x100000000ULL) { + gPEClockFrequencyInfo.cpu_clock_rate_hz = 0xFFFFFFFFUL; + } else { + gPEClockFrequencyInfo.cpu_clock_rate_hz = (unsigned long)cycles; + } + gPEClockFrequencyInfo.cpu_frequency_hz = cycles; - return (KERN_SUCCESS); + kprintf("[RTCLOCK] frequency %llu (%llu)\n", cycles, cyc_per_sec); + return(cycles); } -/* - * Get clock device attributes. - */ -kern_return_t -calend_getattr( - clock_flavor_t flavor, - clock_attr_t attr, /* OUT */ - mach_msg_type_number_t *count) /* IN/OUT */ +void +clock_get_system_microtime( + clock_sec_t *secs, + clock_usec_t *microsecs) { - spl_t s; - - if (*count != 1) - return (KERN_FAILURE); - switch (flavor) { - - case CLOCK_GET_TIME_RES: /* >0 res */ -#if (NCPUS == 1 || (MP_V1_1 && 0)) - LOCK_RTC(s); - *(clock_res_t *) attr = 1000; - UNLOCK_RTC(s); - break; -#else /* (NCPUS == 1 || (MP_V1_1 && 0)) && AT386 */ - LOCK_RTC(s); - *(clock_res_t *) attr = rtclock.intr_nsec; - UNLOCK_RTC(s); - break; -#endif /* (NCPUS == 1 || (MP_V1_1 && 0)) && AT386 */ - - case CLOCK_ALARM_CURRES: /* =0 no alarm */ - case CLOCK_ALARM_MINRES: - case CLOCK_ALARM_MAXRES: - *(clock_res_t *) attr = 0; - break; - - default: - return (KERN_INVALID_VALUE); - } - return (KERN_SUCCESS); + uint64_t now = rtc_nanotime_read(); + + _absolutetime_to_microtime(now, secs, microsecs); } void -clock_adjust_calendar( - clock_res_t nsec) +clock_get_system_nanotime( + clock_sec_t *secs, + clock_nsec_t *nanosecs) { - spl_t s; + uint64_t now = rtc_nanotime_read(); - LOCK_RTC(s); - if (rtclock.calend_is_set) - ADD_MACH_TIMESPEC_NSEC(&rtclock.calend_offset, nsec); - UNLOCK_RTC(s); + _absolutetime_to_nanotime(now, secs, nanosecs); } void -clock_initialize_calendar(void) +clock_gettimeofday_set_commpage( + uint64_t abstime, + uint64_t epoch, + uint64_t offset, + clock_sec_t *secs, + clock_usec_t *microsecs) { - mach_timespec_t bbc_time, curr_time; - spl_t s; - - if (bbc_gettime(&bbc_time) != KERN_SUCCESS) - return; - - LOCK_RTC(s); - if (!rtclock.calend_is_set) { - (void) sysclk_gettime_internal(&curr_time); - rtclock.calend_offset = bbc_time; - SUB_MACH_TIMESPEC(&rtclock.calend_offset, &curr_time); - rtclock.calend_is_set = TRUE; - } - UNLOCK_RTC(s); -} + uint64_t now = abstime + offset; + uint32_t remain; -mach_timespec_t -clock_get_calendar_offset(void) -{ - mach_timespec_t result = MACH_TIMESPEC_ZERO; - spl_t s; + remain = _absolutetime_to_microtime(now, secs, microsecs); - LOCK_RTC(s); - if (rtclock.calend_is_set) - result = rtclock.calend_offset; - UNLOCK_RTC(s); + *secs += (clock_sec_t)epoch; - return (result); + commpage_set_timestamp(abstime - remain, *secs); } void clock_timebase_info( mach_timebase_info_t info) { - spl_t s; - - LOCK_RTC(s); - info->numer = info->denom = 1; - UNLOCK_RTC(s); + info->numer = info->denom = 1; } +/* + * Real-time clock device interrupt. + */ void -clock_set_timer_deadline( - uint64_t deadline) -{ - spl_t s; - - LOCK_RTC(s); - rtclock.timer_deadline = deadline; - rtclock.timer_is_set = TRUE; - UNLOCK_RTC(s); -} - -void -clock_set_timer_func( - clock_timer_func_t func) +rtclock_intr( + x86_saved_state_t *tregs) { - spl_t s; + uint64_t rip; + boolean_t user_mode = FALSE; - LOCK_RTC(s); - if (rtclock.timer_expire == NULL) - rtclock.timer_expire = func; - UNLOCK_RTC(s); -} + assert(get_preemption_level() > 0); + assert(!ml_get_interrupts_enabled()); - + if (is_saved_state64(tregs) == TRUE) { + x86_saved_state64_t *regs; + + regs = saved_state64(tregs); -/* - * Load the count register and start the clock. - */ -#define RTCLOCK_RESET() { \ - outb(PITCTL_PORT, PIT_C0|PIT_NDIVMODE|PIT_READMODE); \ - outb(PITCTR0_PORT, (clks_per_int & 0xff)); \ - outb(PITCTR0_PORT, (clks_per_int >> 8)); \ -} + if (regs->isf.cs & 0x03) + user_mode = TRUE; + rip = regs->isf.rip; + } else { + x86_saved_state32_t *regs; -/* - * Reset the clock device. This causes the realtime clock - * device to reload its mode and count value (frequency). - * Note: the CPU should be calibrated - * before starting the clock for the first time. - */ + regs = saved_state32(tregs); -void -rtclock_reset(void) -{ - int s; - -#if NCPUS > 1 && !(MP_V1_1 && 0) - mp_disable_preemption(); - if (cpu_number() != master_cpu) { - mp_enable_preemption(); - return; + if (regs->cs & 0x03) + user_mode = TRUE; + rip = regs->eip; } - mp_enable_preemption(); -#endif /* NCPUS > 1 && AT386 && !MP_V1_1 */ - LOCK_RTC(s); - RTCLOCK_RESET(); - UNLOCK_RTC(s); + + /* call the generic etimer */ + timer_intr(user_mode, rip); } + /* - * Real-time clock device interrupt. Called only on the - * master processor. Updates the clock time and upcalls - * into the higher level clock code to deliver alarms. + * Request timer pop from the hardware */ -int -rtclock_intr(void) -{ - uint64_t abstime; - mach_timespec_t clock_time; - int i; - spl_t s; - - /* - * Update clock time. Do the update so that the macro - * MTS_TO_TS() for reading the mapped time works (e.g. - * update in order: mtv_csec, mtv_time.tv_nsec, mtv_time.tv_sec). - */ - LOCK_RTC(s); - rdtsc_hilo(&rtc_last_int_tsc_hi, &rtc_last_int_tsc_lo); - i = rtclock.time.tv_nsec + rtclock.intr_nsec; - if (i < NSEC_PER_SEC) - rtclock.time.tv_nsec = i; - else { - rtclock.time.tv_nsec = i - NSEC_PER_SEC; - rtclock.time.tv_sec++; - } - /* note time now up to date */ - last_ival = 0; - rtclock.abstime += rtclock.intr_nsec; - abstime = rtclock.abstime; - if ( rtclock.timer_is_set && - rtclock.timer_deadline <= abstime ) { - rtclock.timer_is_set = FALSE; - UNLOCK_RTC(s); - - (*rtclock.timer_expire)(abstime); +uint64_t +setPop(uint64_t time) +{ + uint64_t now; + uint64_t pop; - LOCK_RTC(s); + /* 0 and EndOfAllTime are special-cases for "clear the timer" */ + if (time == 0 || time == EndOfAllTime ) { + time = EndOfAllTime; + now = 0; + pop = rtc_timer->rtc_set(0, 0); + } else { + now = rtc_nanotime_read(); /* The time in nanoseconds */ + pop = rtc_timer->rtc_set(time, now); } - /* - * Perform alarm clock processing if needed. The time - * passed up is incremented by a half-interrupt tick - * to trigger alarms closest to their desired times. - * The clock_alarm_intr() routine calls sysclk_setalrm() - * before returning if later alarms are pending. - */ - - if (RtcAlrm && (RtcAlrm->tv_sec < RtcTime->tv_sec || - (RtcAlrm->tv_sec == RtcTime->tv_sec && - RtcDelt >= RtcAlrm->tv_nsec - RtcTime->tv_nsec))) { - clock_time.tv_sec = 0; - clock_time.tv_nsec = RtcDelt; - ADD_MACH_TIMESPEC (&clock_time, RtcTime); - RtcAlrm = 0; - UNLOCK_RTC(s); - /* - * Call clock_alarm_intr() without RTC-lock. - * The lock ordering is always CLOCK-lock - * before RTC-lock. - */ - clock_alarm_intr(SYSTEM_CLOCK, &clock_time); - LOCK_RTC(s); - } + /* Record requested and actual deadlines set */ + x86_lcpu()->rtcDeadline = time; + x86_lcpu()->rtcPop = pop; - /* - * On a HZ-tick boundary: return 0 and adjust the clock - * alarm resolution (if requested). Otherwise return a - * non-zero value. - */ - if ((i = --rtc_intr_count) == 0) { - if (rtclock.new_ires) { - rtc_setvals(new_clknum, rtclock.new_ires); - RTCLOCK_RESET(); /* lock clock register */ - rtclock.new_ires = 0; - } - rtc_intr_count = rtc_intr_hertz; - } - UNLOCK_RTC(s); - return (i); + return pop - now; } -void -clock_get_uptime( - uint64_t *result) +uint64_t +mach_absolute_time(void) { - uint32_t ticks; - spl_t s; - - LOCK_RTC(s); - ticks = get_uptime_cycles(); - *result = rtclock.abstime; - UNLOCK_RTC(s); - - *result += ticks; + return rtc_nanotime_read(); } void -clock_interval_to_deadline( +clock_interval_to_absolutetime_interval( uint32_t interval, uint32_t scale_factor, uint64_t *result) { - uint64_t abstime; - - clock_get_uptime(result); - - clock_interval_to_absolutetime_interval(interval, scale_factor, &abstime); - - *result += abstime; + *result = (uint64_t)interval * scale_factor; } void -clock_interval_to_absolutetime_interval( - uint32_t interval, - uint32_t scale_factor, - uint64_t *result) +absolutetime_to_microtime( + uint64_t abstime, + clock_sec_t *secs, + clock_usec_t *microsecs) { - *result = (uint64_t)interval * scale_factor; + _absolutetime_to_microtime(abstime, secs, microsecs); } void -clock_absolutetime_interval_to_deadline( - uint64_t abstime, - uint64_t *result) +nanotime_to_absolutetime( + clock_sec_t secs, + clock_nsec_t nanosecs, + uint64_t *result) { - clock_get_uptime(result); - - *result += abstime; + *result = ((uint64_t)secs * NSEC_PER_SEC) + nanosecs; } void @@ -1039,87 +534,13 @@ nanoseconds_to_absolutetime( *result = nanoseconds; } -/* - * measure_delay(microseconds) - * - * Measure elapsed time for delay calls - * Returns microseconds. - * - * Microseconds must not be too large since the counter (short) - * will roll over. Max is about 13 ms. Values smaller than 1 ms are ok. - * This uses the assumed frequency of the rt clock which is emperically - * accurate to only about 200 ppm. - */ - -int -measure_delay( - int us) -{ - unsigned int lsb, val; - - outb(PITCTL_PORT, PIT_C0|PIT_NDIVMODE|PIT_READMODE); - outb(PITCTR0_PORT, 0xff); /* set counter to max value */ - outb(PITCTR0_PORT, 0xff); - delay(us); - outb(PITCTL_PORT, PIT_C0); - lsb = inb(PITCTR0_PORT); - val = (inb(PITCTR0_PORT) << 8) | lsb; - val = 0xffff - val; - val *= 1000000; - val /= CLKNUM; - return(val); -} - -/* - * calibrate_delay(void) - * - * Adjust delaycount. Called from startup before clock is started - * for normal interrupt generation. - */ - void -calibrate_delay(void) +machine_delay_until( + uint64_t interval, + uint64_t deadline) { - unsigned val; - int prev = 0; - register int i; - - printf("adjusting delay count: %d", delaycount); - for (i=0; i<10; i++) { - prev = delaycount; - /* - * microdata must not be too large since measure_timer - * will not return accurate values if the counter (short) - * rolls over - */ - val = measure_delay(microdata); - if (val == 0) { - delaycount *= 2; - } else { - delaycount *= microdata; - delaycount += val-1; /* round up to upper us */ - delaycount /= val; - } - if (delaycount <= 0) - delaycount = 1; - if (delaycount != prev) - printf(" %d", delaycount); - } - printf("\n"); -} - -#if MACH_KDB -void -test_delay(void); - -void -test_delay(void) -{ - register i; - - for (i = 0; i < 10; i++) - printf("%d, %d\n", i, measure_delay(i)); - for (i = 10; i <= 100; i+=10) - printf("%d, %d\n", i, measure_delay(i)); + (void)interval; + while (mach_absolute_time() < deadline) { + cpu_pause(); + } } -#endif /* MACH_KDB */