// SPDX-License-Identifier: GPL-2.0 /* time.c: UltraSparc timer and TOD clock support. * * Copyright (C) 1997, 2008 David S. Miller (davem@davemloft.net) * Copyright (C) 1998 Eddie C. Dost (ecd@skynet.be) * * Based largely on code which is: * * Copyright (C) 1996 Thomas K. Dyas (tdyas@eden.rutgers.edu) */ #include <linux/errno.h> #include <linux/export.h> #include <linux/sched.h> #include <linux/kernel.h> #include <linux/param.h> #include <linux/string.h> #include <linux/mm.h> #include <linux/interrupt.h> #include <linux/time.h> #include <linux/timex.h> #include <linux/init.h> #include <linux/ioport.h> #include <linux/mc146818rtc.h> #include <linux/delay.h> #include <linux/profile.h> #include <linux/bcd.h> #include <linux/jiffies.h> #include <linux/cpufreq.h> #include <linux/percpu.h> #include <linux/rtc/m48t59.h> #include <linux/kernel_stat.h> #include <linux/clockchips.h> #include <linux/clocksource.h> #include <linux/platform_device.h> #include <linux/ftrace.h> #include <asm/oplib.h> #include <asm/timer.h> #include <asm/irq.h> #include <asm/io.h> #include <asm/prom.h> #include <asm/starfire.h> #include <asm/smp.h> #include <asm/sections.h> #include <asm/cpudata.h> #include <linux/uaccess.h> #include <asm/irq_regs.h> #include <asm/cacheflush.h> #include "entry.h" #include "kernel.h" DEFINE_SPINLOCK(rtc_lock); #ifdef CONFIG_SMP unsigned long profile_pc(struct pt_regs *regs) { unsigned long pc = instruction_pointer(regs); if (in_lock_functions(pc)) return regs->u_regs[UREG_RETPC]; return pc; } EXPORT_SYMBOL(profile_pc); #endif static void tick_disable_protection(void) { /* Set things up so user can access tick register for profiling * purposes. Also workaround BB_ERRATA_1 by doing a dummy * read back of %tick after writing it. */ __asm__ __volatile__( " ba,pt %%xcc, 1f\n" " nop\n" " .align 64\n" "1: rd %%tick, %%g2\n" " add %%g2, 6, %%g2\n" " andn %%g2, %0, %%g2\n" " wrpr %%g2, 0, %%tick\n" " rdpr %%tick, %%g0" : /* no outputs */ : "r" (TICK_PRIV_BIT) : "g2"); } static void tick_disable_irq(void) { __asm__ __volatile__( " ba,pt %%xcc, 1f\n" " nop\n" " .align 64\n" "1: wr %0, 0x0, %%tick_cmpr\n" " rd %%tick_cmpr, %%g0" : /* no outputs */ : "r" (TICKCMP_IRQ_BIT)); } static void tick_init_tick(void) { tick_disable_protection(); tick_disable_irq(); } static unsigned long long tick_get_tick(void) { unsigned long ret; __asm__ __volatile__("rd %%tick, %0\n\t" "mov %0, %0" : "=r" (ret)); return ret & ~TICK_PRIV_BIT; } static int tick_add_compare(unsigned long adj) { unsigned long orig_tick, new_tick, new_compare; __asm__ __volatile__("rd %%tick, %0" : "=r" (orig_tick)); orig_tick &= ~TICKCMP_IRQ_BIT; /* Workaround for Spitfire Errata (#54 I think??), I discovered * this via Sun BugID 4008234, mentioned in Solaris-2.5.1 patch * number 103640. * * On Blackbird writes to %tick_cmpr can fail, the * workaround seems to be to execute the wr instruction * at the start of an I-cache line, and perform a dummy * read back from %tick_cmpr right after writing to it. -DaveM */ __asm__ __volatile__("ba,pt %%xcc, 1f\n\t" " add %1, %2, %0\n\t" ".align 64\n" "1:\n\t" "wr %0, 0, %%tick_cmpr\n\t" "rd %%tick_cmpr, %%g0\n\t" : "=r" (new_compare) : "r" (orig_tick), "r" (adj)); __asm__ __volatile__("rd %%tick, %0" : "=r" (new_tick)); new_tick &= ~TICKCMP_IRQ_BIT; return ((long)(new_tick - (orig_tick+adj))) > 0L; } static unsigned long tick_add_tick(unsigned long adj) { unsigned long new_tick; /* Also need to handle Blackbird bug here too. */ __asm__ __volatile__("rd %%tick, %0\n\t" "add %0, %1, %0\n\t" "wrpr %0, 0, %%tick\n\t" : "=&r" (new_tick) : "r" (adj)); return new_tick; } /* Searches for cpu clock frequency with given cpuid in OpenBoot tree */ static unsigned long cpuid_to_freq(phandle node, int cpuid) { bool is_cpu_node = false; unsigned long freq = 0; char type[128]; if (!node) return freq; if (prom_getproperty(node, "device_type", type, sizeof(type)) != -1) is_cpu_node = (strcmp(type, "cpu") == 0); /* try upa-portid then cpuid to get cpuid, see prom_64.c */ if (is_cpu_node && (prom_getint(node, "upa-portid") == cpuid || prom_getint(node, "cpuid") == cpuid)) freq = prom_getintdefault(node, "clock-frequency", 0); if (!freq) freq = cpuid_to_freq(prom_getchild(node), cpuid); if (!freq) freq = cpuid_to_freq(prom_getsibling(node), cpuid); return freq; } static unsigned long tick_get_frequency(void) { return cpuid_to_freq(prom_root_node, hard_smp_processor_id()); } static struct sparc64_tick_ops tick_operations __cacheline_aligned = { .name = "tick", .init_tick = tick_init_tick, .disable_irq = tick_disable_irq, .get_tick = tick_get_tick, .add_tick = tick_add_tick, .add_compare = tick_add_compare, .get_frequency = tick_get_frequency, .softint_mask = 1UL << 0, }; struct sparc64_tick_ops *tick_ops __read_mostly = &tick_operations; EXPORT_SYMBOL(tick_ops); static void stick_disable_irq(void) { __asm__ __volatile__( "wr %0, 0x0, %%asr25" : /* no outputs */ : "r" (TICKCMP_IRQ_BIT)); } static void stick_init_tick(void) { /* Writes to the %tick and %stick register are not * allowed on sun4v. The Hypervisor controls that * bit, per-strand. */ if (tlb_type != hypervisor) { tick_disable_protection(); tick_disable_irq(); /* Let the user get at STICK too. */ __asm__ __volatile__( " rd %%asr24, %%g2\n" " andn %%g2, %0, %%g2\n" " wr %%g2, 0, %%asr24" : /* no outputs */ : "r" (TICK_PRIV_BIT) : "g1", "g2"); } stick_disable_irq(); } static unsigned long long stick_get_tick(void) { unsigned long ret; __asm__ __volatile__("rd %%asr24, %0" : "=r" (ret)); return ret & ~TICK_PRIV_BIT; } static unsigned long stick_add_tick(unsigned long adj) { unsigned long new_tick; __asm__ __volatile__("rd %%asr24, %0\n\t" "add %0, %1, %0\n\t" "wr %0, 0, %%asr24\n\t" : "=&r" (new_tick) : "r" (adj)); return new_tick; } static int stick_add_compare(unsigned long adj) { unsigned long orig_tick, new_tick; __asm__ __volatile__("rd %%asr24, %0" : "=r" (orig_tick)); orig_tick &= ~TICKCMP_IRQ_BIT; __asm__ __volatile__("wr %0, 0, %%asr25" : /* no outputs */ : "r" (orig_tick + adj)); __asm__ __volatile__("rd %%asr24, %0" : "=r" (new_tick)); new_tick &= ~TICKCMP_IRQ_BIT; return ((long)(new_tick - (orig_tick+adj))) > 0L; } static unsigned long stick_get_frequency(void) { return prom_getintdefault(prom_root_node, "stick-frequency", 0); } static struct sparc64_tick_ops stick_operations __read_mostly = { .name = "stick", .init_tick = stick_init_tick, .disable_irq = stick_disable_irq, .get_tick = stick_get_tick, .add_tick = stick_add_tick, .add_compare = stick_add_compare, .get_frequency = stick_get_frequency, .softint_mask = 1UL << 16, }; /* On Hummingbird the STICK/STICK_CMPR register is implemented * in I/O space. There are two 64-bit registers each, the * first holds the low 32-bits of the value and the second holds * the high 32-bits. * * Since STICK is constantly updating, we have to access it carefully. * * The sequence we use to read is: * 1) read high * 2) read low * 3) read high again, if it rolled re-read both low and high again. * * Writing STICK safely is also tricky: * 1) write low to zero * 2) write high * 3) write low */ static unsigned long __hbird_read_stick(void) { unsigned long ret, tmp1, tmp2, tmp3; unsigned long addr = HBIRD_STICK_ADDR+8; __asm__ __volatile__("ldxa [%1] %5, %2\n" "1:\n\t" "sub %1, 0x8, %1\n\t" "ldxa [%1] %5, %3\n\t" "add %1, 0x8, %1\n\t" "ldxa [%1] %5, %4\n\t" "cmp %4, %2\n\t" "bne,a,pn %%xcc, 1b\n\t" " mov %4, %2\n\t" "sllx %4, 32, %4\n\t" "or %3, %4, %0\n\t" : "=&r" (ret), "=&r" (addr), "=&r" (tmp1), "=&r" (tmp2), "=&r" (tmp3) : "i" (ASI_PHYS_BYPASS_EC_E), "1" (addr)); return ret; } static void __hbird_write_stick(unsigned long val) { unsigned long low = (val & 0xffffffffUL); unsigned long high = (val >> 32UL); unsigned long addr = HBIRD_STICK_ADDR; __asm__ __volatile__("stxa %%g0, [%0] %4\n\t" "add %0, 0x8, %0\n\t" "stxa %3, [%0] %4\n\t" "sub %0, 0x8, %0\n\t" "stxa %2, [%0] %4" : "=&r" (addr) : "0" (addr), "r" (low), "r" (high), "i" (ASI_PHYS_BYPASS_EC_E)); } static void __hbird_write_compare(unsigned long val) { unsigned long low = (val & 0xffffffffUL); unsigned long high = (val >> 32UL); unsigned long addr = HBIRD_STICKCMP_ADDR + 0x8UL; __asm__ __volatile__("stxa %3, [%0] %4\n\t" "sub %0, 0x8, %0\n\t" "stxa %2, [%0] %4" : "=&r" (addr) : "0" (addr), "r" (low), "r" (high), "i" (ASI_PHYS_BYPASS_EC_E)); } static void hbtick_disable_irq(void) { __hbird_write_compare(TICKCMP_IRQ_BIT); } static void hbtick_init_tick(void) { tick_disable_protection(); /* XXX This seems to be necessary to 'jumpstart' Hummingbird * XXX into actually sending STICK interrupts. I think because * XXX of how we store %tick_cmpr in head.S this somehow resets the * XXX {TICK + STICK} interrupt mux. -DaveM */ __hbird_write_stick(__hbird_read_stick()); hbtick_disable_irq(); } static unsigned long long hbtick_get_tick(void) { return __hbird_read_stick() & ~TICK_PRIV_BIT; } static unsigned long hbtick_add_tick(unsigned long adj) { unsigned long val; val = __hbird_read_stick() + adj; __hbird_write_stick(val); return val; } static int hbtick_add_compare(unsigned long adj) { unsigned long val = __hbird_read_stick(); unsigned long val2; val &= ~TICKCMP_IRQ_BIT; val += adj; __hbird_write_compare(val); val2 = __hbird_read_stick() & ~TICKCMP_IRQ_BIT; return ((long)(val2 - val)) > 0L; } static unsigned long hbtick_get_frequency(void) { return prom_getintdefault(prom_root_node, "stick-frequency", 0); } static struct sparc64_tick_ops hbtick_operations __read_mostly = { .name = "hbtick", .init_tick = hbtick_init_tick, .disable_irq = hbtick_disable_irq, .get_tick = hbtick_get_tick, .add_tick = hbtick_add_tick, .add_compare = hbtick_add_compare, .get_frequency = hbtick_get_frequency, .softint_mask = 1UL << 0, }; unsigned long cmos_regs; EXPORT_SYMBOL(cmos_regs); static struct resource rtc_cmos_resource; static struct platform_device rtc_cmos_device = { .name = "rtc_cmos", .id = -1, .resource = &rtc_cmos_resource, .num_resources = 1, }; static int rtc_probe(struct platform_device *op) { struct resource *r; printk(KERN_INFO "%pOF: RTC regs at 0x%llx\n", op->dev.of_node, op->resource[0].start); /* The CMOS RTC driver only accepts IORESOURCE_IO, so cons * up a fake resource so that the probe works for all cases. * When the RTC is behind an ISA bus it will have IORESOURCE_IO * already, whereas when it's behind EBUS is will be IORESOURCE_MEM. */ r = &rtc_cmos_resource; r->flags = IORESOURCE_IO; r->name = op->resource[0].name; r->start = op->resource[0].start; r->end = op->resource[0].end; cmos_regs = op->resource[0].start; return platform_device_register(&rtc_cmos_device); } static const struct of_device_id rtc_match[] = { { .name = "rtc", .compatible = "m5819", }, { .name = "rtc", .compatible = "isa-m5819p", }, { .name = "rtc", .compatible = "isa-m5823p", }, { .name = "rtc", .compatible = "ds1287", }, {}, }; static struct platform_driver rtc_driver = { .probe = rtc_probe, .driver = { .name = "rtc", .of_match_table = rtc_match, }, }; static struct platform_device rtc_bq4802_device = { .name = "rtc-bq4802", .id = -1, .num_resources = 1, }; static int bq4802_probe(struct platform_device *op) { printk(KERN_INFO "%pOF: BQ4802 regs at 0x%llx\n", op->dev.of_node, op->resource[0].start); rtc_bq4802_device.resource = &op->resource[0]; return platform_device_register(&rtc_bq4802_device); } static const struct of_device_id bq4802_match[] = { { .name = "rtc", .compatible = "bq4802", }, {}, }; static struct platform_driver bq4802_driver = { .probe = bq4802_probe, .driver = { .name = "bq4802", .of_match_table = bq4802_match, }, }; static unsigned char mostek_read_byte(struct device *dev, u32 ofs) { struct platform_device *pdev = to_platform_device(dev); void __iomem *regs = (void __iomem *) pdev->resource[0].start; return readb(regs + ofs); } static void mostek_write_byte(struct device *dev, u32 ofs, u8 val) { struct platform_device *pdev = to_platform_device(dev); void __iomem *regs = (void __iomem *) pdev->resource[0].start; writeb(val, regs + ofs); } static struct m48t59_plat_data m48t59_data = { .read_byte = mostek_read_byte, .write_byte = mostek_write_byte, }; static struct platform_device m48t59_rtc = { .name = "rtc-m48t59", .id = 0, .num_resources = 1, .dev = { .platform_data = &m48t59_data, }, }; static int mostek_probe(struct platform_device *op) { struct device_node *dp = op->dev.of_node; /* On an Enterprise system there can be multiple mostek clocks. * We should only match the one that is on the central FHC bus. */ if (of_node_name_eq(dp->parent, "fhc") && !of_node_name_eq(dp->parent->parent, "central")) return -ENODEV; printk(KERN_INFO "%pOF: Mostek regs at 0x%llx\n", dp, op->resource[0].start); m48t59_rtc.resource = &op->resource[0]; return platform_device_register(&m48t59_rtc); } static const struct of_device_id mostek_match[] = { { .name = "eeprom", }, {}, }; static struct platform_driver mostek_driver = { .probe = mostek_probe, .driver = { .name = "mostek", .of_match_table = mostek_match, }, }; static struct platform_device rtc_sun4v_device = { .name = "rtc-sun4v", .id = -1, }; static struct platform_device rtc_starfire_device = { .name = "rtc-starfire", .id = -1, }; static int __init clock_init(void) { if (this_is_starfire) return platform_device_register(&rtc_starfire_device); if (tlb_type == hypervisor) return platform_device_register(&rtc_sun4v_device); (void) platform_driver_register(&rtc_driver); (void) platform_driver_register(&mostek_driver); (void) platform_driver_register(&bq4802_driver); return 0; } /* Must be after subsys_initcall() so that busses are probed. Must * be before device_initcall() because things like the RTC driver * need to see the clock registers. */ fs_initcall(clock_init); /* Return true if this is Hummingbird, aka Ultra-IIe */ static bool is_hummingbird(void) { unsigned long ver, manuf, impl; __asm__ __volatile__ ("rdpr %%ver, %0" : "=&r" (ver)); manuf = ((ver >> 48) & 0xffff); impl = ((ver >> 32) & 0xffff); return (manuf == 0x17 && impl == 0x13); } struct freq_table { unsigned long clock_tick_ref; unsigned int ref_freq; }; static DEFINE_PER_CPU(struct freq_table, sparc64_freq_table) = { 0, 0 }; unsigned long sparc64_get_clock_tick(unsigned int cpu) { struct freq_table *ft = &per_cpu(sparc64_freq_table, cpu); if (ft->clock_tick_ref) return ft->clock_tick_ref; return cpu_data(cpu).clock_tick; } EXPORT_SYMBOL(sparc64_get_clock_tick); #ifdef CONFIG_CPU_FREQ static int sparc64_cpufreq_notifier(struct notifier_block *nb, unsigned long val, void *data) { struct cpufreq_freqs *freq = data; unsigned int cpu; struct freq_table *ft; for_each_cpu(cpu, freq->policy->cpus) { ft = &per_cpu(sparc64_freq_table, cpu); if (!ft->ref_freq) { ft->ref_freq = freq->old; ft->clock_tick_ref = cpu_data(cpu).clock_tick; } if ((val == CPUFREQ_PRECHANGE && freq->old < freq->new) || (val == CPUFREQ_POSTCHANGE && freq->old > freq->new)) { cpu_data(cpu).clock_tick = cpufreq_scale(ft->clock_tick_ref, ft->ref_freq, freq->new); } } return 0; } static struct notifier_block sparc64_cpufreq_notifier_block = { .notifier_call = sparc64_cpufreq_notifier }; static int __init register_sparc64_cpufreq_notifier(void) { cpufreq_register_notifier(&sparc64_cpufreq_notifier_block, CPUFREQ_TRANSITION_NOTIFIER); return 0; } core_initcall(register_sparc64_cpufreq_notifier); #endif /* CONFIG_CPU_FREQ */ static int sparc64_next_event(unsigned long delta, struct clock_event_device *evt) { return tick_operations.add_compare(delta) ? -ETIME : 0; } static int sparc64_timer_shutdown(struct clock_event_device *evt) { tick_operations.disable_irq(); return 0; } static struct clock_event_device sparc64_clockevent = { .features = CLOCK_EVT_FEAT_ONESHOT, .set_state_shutdown = sparc64_timer_shutdown, .set_next_event = sparc64_next_event, .rating = 100, .shift = 30, .irq = -1, }; static DEFINE_PER_CPU(struct clock_event_device, sparc64_events); void __irq_entry timer_interrupt(int irq, struct pt_regs *regs) { struct pt_regs *old_regs = set_irq_regs(regs); unsigned long tick_mask = tick_operations.softint_mask; int cpu = smp_processor_id(); struct clock_event_device *evt = &per_cpu(sparc64_events, cpu); clear_softint(tick_mask); irq_enter(); local_cpu_data().irq0_irqs++; kstat_incr_irq_this_cpu(0); if (unlikely(!evt->event_handler)) { printk(KERN_WARNING "Spurious SPARC64 timer interrupt on cpu %d\n", cpu); } else evt->event_handler(evt); irq_exit(); set_irq_regs(old_regs); } void setup_sparc64_timer(void) { struct clock_event_device *sevt; unsigned long pstate; /* Guarantee that the following sequences execute * uninterrupted. */ __asm__ __volatile__("rdpr %%pstate, %0\n\t" "wrpr %0, %1, %%pstate" : "=r" (pstate) : "i" (PSTATE_IE)); tick_operations.init_tick(); /* Restore PSTATE_IE. */ __asm__ __volatile__("wrpr %0, 0x0, %%pstate" : /* no outputs */ : "r" (pstate)); sevt = this_cpu_ptr(&sparc64_events); memcpy(sevt, &sparc64_clockevent, sizeof(*sevt)); sevt->cpumask = cpumask_of(smp_processor_id()); clockevents_register_device(sevt); } #define SPARC64_NSEC_PER_CYC_SHIFT 10UL static struct clocksource clocksource_tick = { .rating = 100, .mask = CLOCKSOURCE_MASK(64), .flags = CLOCK_SOURCE_IS_CONTINUOUS, }; static unsigned long tb_ticks_per_usec __read_mostly; void __delay(unsigned long loops) { unsigned long bclock = get_tick(); while ((get_tick() - bclock) < loops) ; } EXPORT_SYMBOL(__delay); void udelay(unsigned long usecs) { __delay(tb_ticks_per_usec * usecs); } EXPORT_SYMBOL(udelay); static u64 clocksource_tick_read(struct clocksource *cs) { return get_tick(); } static void __init get_tick_patch(void) { unsigned int *addr, *instr, i; struct get_tick_patch *p; if (tlb_type == spitfire && is_hummingbird()) return; for (p = &__get_tick_patch; p < &__get_tick_patch_end; p++) { instr = (tlb_type == spitfire) ? p->tick : p->stick; addr = (unsigned int *)(unsigned long)p->addr; for (i = 0; i < GET_TICK_NINSTR; i++) { addr[i] = instr[i]; /* ensure that address is modified before flush */ wmb(); flushi(&addr[i]); } } } static void __init init_tick_ops(struct sparc64_tick_ops *ops) { unsigned long freq, quotient, tick; freq = ops->get_frequency(); quotient = clocksource_hz2mult(freq, SPARC64_NSEC_PER_CYC_SHIFT); tick = ops->get_tick(); ops->offset = (tick * quotient) >> SPARC64_NSEC_PER_CYC_SHIFT; ops->ticks_per_nsec_quotient = quotient; ops->frequency = freq; tick_operations = *ops; get_tick_patch(); } void __init time_init_early(void) { if (tlb_type == spitfire) { if (is_hummingbird()) { init_tick_ops(&hbtick_operations); clocksource_tick.archdata.vclock_mode = VCLOCK_NONE; } else { init_tick_ops(&tick_operations); clocksource_tick.archdata.vclock_mode = VCLOCK_TICK; } } else { init_tick_ops(&stick_operations); clocksource_tick.archdata.vclock_mode = VCLOCK_STICK; } } void __init time_init(void) { unsigned long freq; freq = tick_operations.frequency; tb_ticks_per_usec = freq / USEC_PER_SEC; clocksource_tick.name = tick_operations.name; clocksource_tick.read = clocksource_tick_read; clocksource_register_hz(&clocksource_tick, freq); printk("clocksource: mult[%x] shift[%d]\n", clocksource_tick.mult, clocksource_tick.shift); sparc64_clockevent.name = tick_operations.name; clockevents_calc_mult_shift(&sparc64_clockevent, freq, 4); sparc64_clockevent.max_delta_ns = clockevent_delta2ns(0x7fffffffffffffffUL, &sparc64_clockevent); sparc64_clockevent.max_delta_ticks = 0x7fffffffffffffffUL; sparc64_clockevent.min_delta_ns = clockevent_delta2ns(0xF, &sparc64_clockevent); sparc64_clockevent.min_delta_ticks = 0xF; printk("clockevent: mult[%x] shift[%d]\n", sparc64_clockevent.mult, sparc64_clockevent.shift); setup_sparc64_timer(); } unsigned long long sched_clock(void) { unsigned long quotient = tick_operations.ticks_per_nsec_quotient; unsigned long offset = tick_operations.offset; /* Use barrier so the compiler emits the loads first and overlaps load * latency with reading tick, because reading %tick/%stick is a * post-sync instruction that will flush and restart subsequent * instructions after it commits. */ barrier(); return ((get_tick() * quotient) >> SPARC64_NSEC_PER_CYC_SHIFT) - offset; } int read_current_timer(unsigned long *timer_val) { *timer_val = get_tick(); return 0; }