diff options
Diffstat (limited to 'arch/x86/kernel/hpet.c')
| -rw-r--r-- | arch/x86/kernel/hpet.c | 274 |
1 files changed, 152 insertions, 122 deletions
diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c index ba6e6588460..319bcb9372f 100644 --- a/arch/x86/kernel/hpet.c +++ b/arch/x86/kernel/hpet.c @@ -1,9 +1,11 @@ #include <linux/clocksource.h> #include <linux/clockchips.h> #include <linux/interrupt.h> -#include <linux/sysdev.h> +#include <linux/export.h> #include <linux/delay.h> #include <linux/errno.h> +#include <linux/i8253.h> +#include <linux/slab.h> #include <linux/hpet.h> #include <linux/init.h> #include <linux/cpu.h> @@ -11,11 +13,10 @@ #include <linux/io.h> #include <asm/fixmap.h> -#include <asm/i8253.h> #include <asm/hpet.h> +#include <asm/time.h> #define HPET_MASK CLOCKSOURCE_MASK(32) -#define HPET_SHIFT 22 /* FSEC = 10^-15 NSEC = 10^-9 */ @@ -27,13 +28,16 @@ #define HPET_DEV_FSB_CAP 0x1000 #define HPET_DEV_PERI_CAP 0x2000 -#define EVT_TO_HPET_DEV(evt) container_of(evt, struct hpet_dev, evt) +#define HPET_MIN_CYCLES 128 +#define HPET_MIN_PROG_DELTA (HPET_MIN_CYCLES + (HPET_MIN_CYCLES >> 1)) /* * HPET address is set in acpi/boot.c, when an ACPI entry exists */ unsigned long hpet_address; u8 hpet_blockid; /* OS timer block num */ +u8 hpet_msi_disable; + #ifdef CONFIG_PCI_MSI static unsigned long hpet_num_timers; #endif @@ -48,6 +52,11 @@ struct hpet_dev { char name[10]; }; +inline struct hpet_dev *EVT_TO_HPET_DEV(struct clock_event_device *evtdev) +{ + return container_of(evtdev, struct hpet_dev, evt); +} + inline unsigned int hpet_readl(unsigned int a) { return readl(hpet_virt_address + a); @@ -65,9 +74,6 @@ static inline void hpet_writel(unsigned int d, unsigned int a) static inline void hpet_set_mapping(void) { hpet_virt_address = ioremap_nocache(hpet_address, HPET_MMAP_SIZE); -#ifdef CONFIG_X86_64 - __set_fixmap(VSYSCALL_HPET, hpet_address, PAGE_KERNEL_VSYSCALL_NOCACHE); -#endif } static inline void hpet_clear_mapping(void) @@ -79,19 +85,24 @@ static inline void hpet_clear_mapping(void) /* * HPET command line enable / disable */ -static int boot_hpet_disable; +int boot_hpet_disable; int hpet_force_user; static int hpet_verbose; static int __init hpet_setup(char *str) { - if (str) { + while (str) { + char *next = strchr(str, ','); + + if (next) + *next++ = 0; if (!strncmp("disable", str, 7)) boot_hpet_disable = 1; if (!strncmp("force", str, 5)) hpet_force_user = 1; if (!strncmp("verbose", str, 7)) hpet_verbose = 1; + str = next; } return 1; } @@ -212,7 +223,7 @@ static void hpet_reserve_platform_timers(unsigned int id) { } /* * Common hpet info */ -static unsigned long hpet_period; +static unsigned long hpet_freq; static void hpet_legacy_set_mode(enum clock_event_mode mode, struct clock_event_device *evt); @@ -227,7 +238,6 @@ static struct clock_event_device hpet_clockevent = { .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, .set_mode = hpet_legacy_set_mode, .set_next_event = hpet_legacy_next_event, - .shift = 32, .irq = 0, .rating = 50, }; @@ -264,7 +274,7 @@ static void hpet_resume_device(void) force_hpet_resume(); } -static void hpet_resume_counter(void) +static void hpet_resume_counter(struct clocksource *cs) { hpet_resume_device(); hpet_restart_counter(); @@ -285,27 +295,12 @@ static void hpet_legacy_clockevent_register(void) hpet_enable_legacy_int(); /* - * The mult factor is defined as (include/linux/clockchips.h) - * mult/2^shift = cyc/ns (in contrast to ns/cyc in clocksource.h) - * hpet_period is in units of femtoseconds (per cycle), so - * mult/2^shift = cyc/ns = 10^6/hpet_period - * mult = (10^6 * 2^shift)/hpet_period - * mult = (FSEC_PER_NSEC << hpet_clockevent.shift)/hpet_period - */ - hpet_clockevent.mult = div_sc((unsigned long) FSEC_PER_NSEC, - hpet_period, hpet_clockevent.shift); - /* Calculate the min / max delta */ - hpet_clockevent.max_delta_ns = clockevent_delta2ns(0x7FFFFFFF, - &hpet_clockevent); - /* 5 usec minimum reprogramming delta. */ - hpet_clockevent.min_delta_ns = 5000; - - /* * Start hpet with the boot cpu mask and make it * global after the IO_APIC has been initialized. */ hpet_clockevent.cpumask = cpumask_of(smp_processor_id()); - clockevents_register_device(&hpet_clockevent); + clockevents_config_and_register(&hpet_clockevent, hpet_freq, + HPET_MIN_PROG_DELTA, 0x7FFFFFFF); global_clock_event = &hpet_clockevent; printk(KERN_DEBUG "hpet clockevent registered\n"); } @@ -326,8 +321,6 @@ static void hpet_set_mode(enum clock_event_mode mode, now = hpet_readl(HPET_COUNTER); cmp = now + (unsigned int) delta; cfg = hpet_readl(HPET_Tn_CFG(timer)); - /* Make sure we use edge triggered interrupts */ - cfg &= ~HPET_TN_LEVEL; cfg |= HPET_TN_ENABLE | HPET_TN_PERIODIC | HPET_TN_SETVAL | HPET_TN_32BIT; hpet_writel(cfg, HPET_Tn_CFG(timer)); @@ -378,30 +371,37 @@ static int hpet_next_event(unsigned long delta, struct clock_event_device *evt, int timer) { u32 cnt; + s32 res; cnt = hpet_readl(HPET_COUNTER); cnt += (u32) delta; hpet_writel(cnt, HPET_Tn_CMP(timer)); /* - * We need to read back the CMP register on certain HPET - * implementations (ATI chipsets) which seem to delay the - * transfer of the compare register into the internal compare - * logic. With small deltas this might actually be too late as - * the counter could already be higher than the compare value - * at that point and we would wait for the next hpet interrupt - * forever. We found out that reading the CMP register back - * forces the transfer so we can rely on the comparison with - * the counter register below. If the read back from the - * compare register does not match the value we programmed - * then we might have a real hardware problem. We can not do - * much about it here, but at least alert the user/admin with - * a prominent warning. + * HPETs are a complete disaster. The compare register is + * based on a equal comparison and neither provides a less + * than or equal functionality (which would require to take + * the wraparound into account) nor a simple count down event + * mode. Further the write to the comparator register is + * delayed internally up to two HPET clock cycles in certain + * chipsets (ATI, ICH9,10). Some newer AMD chipsets have even + * longer delays. We worked around that by reading back the + * compare register, but that required another workaround for + * ICH9,10 chips where the first readout after write can + * return the old stale value. We already had a minimum + * programming delta of 5us enforced, but a NMI or SMI hitting + * between the counter readout and the comparator write can + * move us behind that point easily. Now instead of reading + * the compare register back several times, we make the ETIME + * decision based on the following: Return ETIME if the + * counter value after the write is less than HPET_MIN_CYCLES + * away from the event or if the counter is already ahead of + * the event. The minimum programming delta for the generic + * clockevents code is set to 1.5 * HPET_MIN_CYCLES. */ - WARN_ONCE(hpet_readl(HPET_Tn_CMP(timer)) != cnt, - KERN_WARNING "hpet: compare register read back failed.\n"); + res = (s32)(cnt - hpet_readl(HPET_COUNTER)); - return (s32)(hpet_readl(HPET_COUNTER) - cnt) >= 0 ? -ETIME : 0; + return res < HPET_MIN_CYCLES ? -ETIME : 0; } static void hpet_legacy_set_mode(enum clock_event_mode mode, @@ -424,40 +424,36 @@ static int hpet_legacy_next_event(unsigned long delta, static DEFINE_PER_CPU(struct hpet_dev *, cpu_hpet_dev); static struct hpet_dev *hpet_devs; -void hpet_msi_unmask(unsigned int irq) +void hpet_msi_unmask(struct irq_data *data) { - struct hpet_dev *hdev = get_irq_data(irq); + struct hpet_dev *hdev = data->handler_data; unsigned int cfg; /* unmask it */ cfg = hpet_readl(HPET_Tn_CFG(hdev->num)); - cfg |= HPET_TN_FSB; + cfg |= HPET_TN_ENABLE | HPET_TN_FSB; hpet_writel(cfg, HPET_Tn_CFG(hdev->num)); } -void hpet_msi_mask(unsigned int irq) +void hpet_msi_mask(struct irq_data *data) { + struct hpet_dev *hdev = data->handler_data; unsigned int cfg; - struct hpet_dev *hdev = get_irq_data(irq); /* mask it */ cfg = hpet_readl(HPET_Tn_CFG(hdev->num)); - cfg &= ~HPET_TN_FSB; + cfg &= ~(HPET_TN_ENABLE | HPET_TN_FSB); hpet_writel(cfg, HPET_Tn_CFG(hdev->num)); } -void hpet_msi_write(unsigned int irq, struct msi_msg *msg) +void hpet_msi_write(struct hpet_dev *hdev, struct msi_msg *msg) { - struct hpet_dev *hdev = get_irq_data(irq); - hpet_writel(msg->data, HPET_Tn_ROUTE(hdev->num)); hpet_writel(msg->address_lo, HPET_Tn_ROUTE(hdev->num) + 4); } -void hpet_msi_read(unsigned int irq, struct msi_msg *msg) +void hpet_msi_read(struct hpet_dev *hdev, struct msi_msg *msg) { - struct hpet_dev *hdev = get_irq_data(irq); - msg->data = hpet_readl(HPET_Tn_ROUTE(hdev->num)); msg->address_lo = hpet_readl(HPET_Tn_ROUTE(hdev->num) + 4); msg->address_hi = 0; @@ -479,8 +475,8 @@ static int hpet_msi_next_event(unsigned long delta, static int hpet_setup_msi_irq(unsigned int irq) { - if (arch_setup_hpet_msi(irq, hpet_blockid)) { - destroy_irq(irq); + if (x86_msi.setup_hpet_msi(irq, hpet_blockid)) { + irq_free_hwirq(irq); return -EINVAL; } return 0; @@ -488,13 +484,12 @@ static int hpet_setup_msi_irq(unsigned int irq) static int hpet_assign_irq(struct hpet_dev *dev) { - unsigned int irq; + unsigned int irq = irq_alloc_hwirq(-1); - irq = create_irq(); if (!irq) return -EINVAL; - set_irq_data(irq, dev); + irq_set_handler_data(irq, dev); if (hpet_setup_msi_irq(irq)) return -EINVAL; @@ -522,7 +517,7 @@ static int hpet_setup_irq(struct hpet_dev *dev) { if (request_irq(dev->irq, hpet_interrupt_handler, - IRQF_TIMER | IRQF_DISABLED | IRQF_NOBALANCING, + IRQF_TIMER | IRQF_NOBALANCING, dev->name, dev)) return -1; @@ -540,7 +535,6 @@ static int hpet_setup_irq(struct hpet_dev *dev) static void init_one_hpet_msi_clockevent(struct hpet_dev *hdev, int cpu) { struct clock_event_device *evt = &hdev->evt; - uint64_t hpet_freq; WARN_ON(cpu != smp_processor_id()); if (!(hdev->flags & HPET_DEV_VALID)) @@ -562,24 +556,10 @@ static void init_one_hpet_msi_clockevent(struct hpet_dev *hdev, int cpu) evt->set_mode = hpet_msi_set_mode; evt->set_next_event = hpet_msi_next_event; - evt->shift = 32; - - /* - * The period is a femto seconds value. We need to calculate the - * scaled math multiplication factor for nanosecond to hpet tick - * conversion. - */ - hpet_freq = 1000000000000000ULL; - do_div(hpet_freq, hpet_period); - evt->mult = div_sc((unsigned long) hpet_freq, - NSEC_PER_SEC, evt->shift); - /* Calculate the max delta */ - evt->max_delta_ns = clockevent_delta2ns(0x7FFFFFFF, evt); - /* 5 usec minimum reprogramming delta. */ - evt->min_delta_ns = 5000; - evt->cpumask = cpumask_of(hdev->cpu); - clockevents_register_device(evt); + + clockevents_config_and_register(evt, hpet_freq, HPET_MIN_PROG_DELTA, + 0x7FFFFFFF); } #ifdef CONFIG_HPET @@ -596,6 +576,9 @@ static void hpet_msi_capability_lookup(unsigned int start_timer) unsigned int num_timers_used = 0; int i; + if (hpet_msi_disable) + return; + if (boot_cpu_has(X86_FEATURE_ARAT)) return; id = hpet_readl(HPET_ID); @@ -707,12 +690,12 @@ static int hpet_cpuhp_notify(struct notifier_block *n, switch (action & 0xf) { case CPU_ONLINE: - INIT_DELAYED_WORK_ON_STACK(&work.work, hpet_work); + INIT_DELAYED_WORK_ONSTACK(&work.work, hpet_work); init_completion(&work.complete); /* FIXME: add schedule_work_on() */ schedule_delayed_work_on(cpu, &work.work, 0); wait_for_completion(&work.complete); - destroy_timer_on_stack(&work.work.timer); + destroy_delayed_work_on_stack(&work.work); break; case CPU_DEAD: if (hdev) { @@ -758,24 +741,14 @@ static cycle_t read_hpet(struct clocksource *cs) return (cycle_t)hpet_readl(HPET_COUNTER); } -#ifdef CONFIG_X86_64 -static cycle_t __vsyscall_fn vread_hpet(void) -{ - return readl((const void __iomem *)fix_to_virt(VSYSCALL_HPET) + 0xf0); -} -#endif - static struct clocksource clocksource_hpet = { .name = "hpet", .rating = 250, .read = read_hpet, .mask = HPET_MASK, - .shift = HPET_SHIFT, .flags = CLOCK_SOURCE_IS_CONTINUOUS, .resume = hpet_resume_counter, -#ifdef CONFIG_X86_64 - .vread = vread_hpet, -#endif + .archdata = { .vclock_mode = VCLOCK_HPET }, }; static int hpet_clocksource_register(void) @@ -807,28 +780,20 @@ static int hpet_clocksource_register(void) return -ENODEV; } - /* - * The definition of mult is (include/linux/clocksource.h) - * mult/2^shift = ns/cyc and hpet_period is in units of fsec/cyc - * so we first need to convert hpet_period to ns/cyc units: - * mult/2^shift = ns/cyc = hpet_period/10^6 - * mult = (hpet_period * 2^shift)/10^6 - * mult = (hpet_period << shift)/FSEC_PER_NSEC - */ - clocksource_hpet.mult = div_sc(hpet_period, FSEC_PER_NSEC, HPET_SHIFT); - - clocksource_register(&clocksource_hpet); - + clocksource_register_hz(&clocksource_hpet, (u32)hpet_freq); return 0; } +static u32 *hpet_boot_cfg; + /** * hpet_enable - Try to setup the HPET timer. Returns 1 on success. */ int __init hpet_enable(void) { - unsigned int id; - int i; + u32 hpet_period, cfg, id; + u64 freq; + unsigned int i, last; if (!is_hpet_capable()) return 0; @@ -866,21 +831,59 @@ int __init hpet_enable(void) goto out_nohpet; /* + * The period is a femto seconds value. Convert it to a + * frequency. + */ + freq = FSEC_PER_SEC; + do_div(freq, hpet_period); + hpet_freq = freq; + + /* * Read the HPET ID register to retrieve the IRQ routing * information and the number of channels */ id = hpet_readl(HPET_ID); hpet_print_config(); + last = (id & HPET_ID_NUMBER) >> HPET_ID_NUMBER_SHIFT; + #ifdef CONFIG_HPET_EMULATE_RTC /* * The legacy routing mode needs at least two channels, tick timer * and the rtc emulation channel. */ - if (!(id & HPET_ID_NUMBER)) + if (!last) goto out_nohpet; #endif + cfg = hpet_readl(HPET_CFG); + hpet_boot_cfg = kmalloc((last + 2) * sizeof(*hpet_boot_cfg), + GFP_KERNEL); + if (hpet_boot_cfg) + *hpet_boot_cfg = cfg; + else + pr_warn("HPET initial state will not be saved\n"); + cfg &= ~(HPET_CFG_ENABLE | HPET_CFG_LEGACY); + hpet_writel(cfg, HPET_CFG); + if (cfg) + pr_warn("HPET: Unrecognized bits %#x set in global cfg\n", + cfg); + + for (i = 0; i <= last; ++i) { + cfg = hpet_readl(HPET_Tn_CFG(i)); + if (hpet_boot_cfg) + hpet_boot_cfg[i + 1] = cfg; + cfg &= ~(HPET_TN_ENABLE | HPET_TN_LEVEL | HPET_TN_FSB); + hpet_writel(cfg, HPET_Tn_CFG(i)); + cfg &= ~(HPET_TN_PERIODIC | HPET_TN_PERIODIC_CAP + | HPET_TN_64BIT_CAP | HPET_TN_32BIT | HPET_TN_ROUTE + | HPET_TN_FSB | HPET_TN_FSB_CAP); + if (cfg) + pr_warn("HPET: Unrecognized bits %#x set in cfg#%u\n", + cfg, i); + } + hpet_print_config(); + if (hpet_clocksource_register()) goto out_nohpet; @@ -928,15 +931,20 @@ static __init int hpet_late_init(void) hpet_reserve_platform_timers(hpet_readl(HPET_ID)); hpet_print_config(); + if (hpet_msi_disable) + return 0; + if (boot_cpu_has(X86_FEATURE_ARAT)) return 0; + cpu_notifier_register_begin(); for_each_online_cpu(cpu) { hpet_cpuhp_notify(NULL, CPU_ONLINE, (void *)(long)cpu); } /* This notifier should be called after workqueue is ready */ - hotcpu_notifier(hpet_cpuhp_notify, -20); + __hotcpu_notifier(hpet_cpuhp_notify, -20); + cpu_notifier_register_done(); return 0; } @@ -944,15 +952,29 @@ fs_initcall(hpet_late_init); void hpet_disable(void) { - if (is_hpet_capable()) { - unsigned int cfg = hpet_readl(HPET_CFG); + if (is_hpet_capable() && hpet_virt_address) { + unsigned int cfg = hpet_readl(HPET_CFG), id, last; - if (hpet_legacy_int_enabled) { + if (hpet_boot_cfg) + cfg = *hpet_boot_cfg; + else if (hpet_legacy_int_enabled) { cfg &= ~HPET_CFG_LEGACY; hpet_legacy_int_enabled = 0; } cfg &= ~HPET_CFG_ENABLE; hpet_writel(cfg, HPET_CFG); + + if (!hpet_boot_cfg) + return; + + id = hpet_readl(HPET_ID); + last = ((id & HPET_ID_NUMBER) >> HPET_ID_NUMBER_SHIFT); + + for (id = 0; id <= last; ++id) + hpet_writel(hpet_boot_cfg[id + 1], HPET_Tn_CFG(id)); + + if (*hpet_boot_cfg & HPET_CFG_ENABLE) + hpet_writel(*hpet_boot_cfg, HPET_CFG); } } @@ -1073,6 +1095,14 @@ int hpet_rtc_timer_init(void) } EXPORT_SYMBOL_GPL(hpet_rtc_timer_init); +static void hpet_disable_rtc_channel(void) +{ + unsigned long cfg; + cfg = hpet_readl(HPET_T1_CFG); + cfg &= ~HPET_TN_ENABLE; + hpet_writel(cfg, HPET_T1_CFG); +} + /* * The functions below are called from rtc driver. * Return 0 if HPET is not being used. @@ -1084,6 +1114,9 @@ int hpet_mask_rtc_irq_bit(unsigned long bit_mask) return 0; hpet_rtc_flags &= ~bit_mask; + if (unlikely(!hpet_rtc_flags)) + hpet_disable_rtc_channel(); + return 1; } EXPORT_SYMBOL_GPL(hpet_mask_rtc_irq_bit); @@ -1135,6 +1168,7 @@ int hpet_set_periodic_freq(unsigned long freq) do_div(clc, freq); clc >>= hpet_clockevent.shift; hpet_pie_delta = clc; + hpet_pie_limit = 0; } return 1; } @@ -1148,15 +1182,11 @@ EXPORT_SYMBOL_GPL(hpet_rtc_dropped_irq); static void hpet_rtc_timer_reinit(void) { - unsigned int cfg, delta; + unsigned int delta; int lost_ints = -1; - if (unlikely(!hpet_rtc_flags)) { - cfg = hpet_readl(HPET_T1_CFG); - cfg &= ~HPET_TN_ENABLE; - hpet_writel(cfg, HPET_T1_CFG); - return; - } + if (unlikely(!hpet_rtc_flags)) + hpet_disable_rtc_channel(); if (!(hpet_rtc_flags & RTC_PIE) || hpet_pie_limit) delta = hpet_default_delta; |