From: Thomas Gleixner Convert HPET to clockevents. Integrate the HPET clocksource and the timer related code into one file. Existing non-high-res functionality is unchanged. Signed-off-by: Thomas Gleixner Signed-off-by: Ingo Molnar Signed-off-by: Andrew Morton --- arch/i386/kernel/Makefile | 1 arch/i386/kernel/hpet.c | 489 +++++++++++++++++++++++++++++++- arch/i386/kernel/i8259.c | 6 arch/i386/kernel/time.c | 20 - arch/i386/kernel/time_hpet.c | 492 --------------------------------- include/asm-i386/hpet.h | 15 - 6 files changed, 484 insertions(+), 539 deletions(-) diff -puN arch/i386/kernel/Makefile~clockevents-i386-hpet-driver arch/i386/kernel/Makefile --- a/arch/i386/kernel/Makefile~clockevents-i386-hpet-driver +++ a/arch/i386/kernel/Makefile @@ -32,7 +32,6 @@ obj-$(CONFIG_KPROBES) += kprobes.o obj-$(CONFIG_MODULES) += module.o obj-y += sysenter.o vsyscall.o obj-$(CONFIG_ACPI_SRAT) += srat.o -obj-$(CONFIG_HPET_TIMER) += time_hpet.o obj-$(CONFIG_EFI) += efi.o efi_stub.o obj-$(CONFIG_DOUBLEFAULT) += doublefault.o obj-$(CONFIG_VM86) += vm86.o diff -puN arch/i386/kernel/hpet.c~clockevents-i386-hpet-driver arch/i386/kernel/hpet.c --- a/arch/i386/kernel/hpet.c~clockevents-i386-hpet-driver +++ a/arch/i386/kernel/hpet.c @@ -1,4 +1,5 @@ #include +#include #include #include #include @@ -6,17 +7,272 @@ #include #include +extern struct clock_event_device *global_clock_event; + #define HPET_MASK CLOCKSOURCE_MASK(32) #define HPET_SHIFT 22 /* FSEC = 10^-15 NSEC = 10^-9 */ #define FSEC_PER_NSEC 1000000 -static void *hpet_ptr; +/* + * HPET address is set in acpi/boot.c, when an ACPI entry exists + */ +unsigned long hpet_address; +static void __iomem * hpet_virt_address; + +static inline unsigned long hpet_readl(unsigned long a) +{ + return readl(hpet_virt_address + a); +} + +static inline void hpet_writel(unsigned long d, unsigned long a) +{ + writel(d, hpet_virt_address + a); +} + +/* + * HPET command line enable / disable + */ +static int boot_hpet_disable; + +static int __init hpet_setup(char* str) +{ + if (str) { + if (!strncmp("disable", str, 7)) + boot_hpet_disable = 1; + } + return 1; +} +__setup("hpet=", hpet_setup); + +static inline int is_hpet_capable(void) +{ + return (!boot_hpet_disable && hpet_address); +} + +/* + * HPET timer interrupt enable / disable + */ +static int hpet_legacy_int_enabled; + +/** + * is_hpet_enabled - check whether the hpet timer interrupt is enabled + */ +int is_hpet_enabled(void) +{ + return is_hpet_capable() && hpet_legacy_int_enabled; +} + +/* + * When the hpet driver (/dev/hpet) is enabled, we need to reserve + * timer 0 and timer 1 in case of RTC emulation. + */ +#ifdef CONFIG_HPET +static void hpet_reserve_platform_timers(unsigned long id) +{ + struct hpet __iomem *hpet = hpet_virt_address; + struct hpet_timer __iomem *timer = &hpet->hpet_timers[2]; + unsigned int nrtimers, i; + struct hpet_data hd; + + nrtimers = ((id & HPET_ID_NUMBER) >> HPET_ID_NUMBER_SHIFT) + 1; + + memset(&hd, 0, sizeof (hd)); + hd.hd_phys_address = hpet_address; + hd.hd_address = hpet_virt_address; + hd.hd_nirqs = nrtimers; + hd.hd_flags = HPET_DATA_PLATFORM; + hpet_reserve_timer(&hd, 0); + +#ifdef CONFIG_HPET_EMULATE_RTC + hpet_reserve_timer(&hd, 1); +#endif + + hd.hd_irq[0] = HPET_LEGACY_8254; + hd.hd_irq[1] = HPET_LEGACY_RTC; + + for (i = 2; i < nrtimers; timer++, i++) + hd.hd_irq[i] = (timer->hpet_config & Tn_INT_ROUTE_CNF_MASK) >> + Tn_INT_ROUTE_CNF_SHIFT; + + hpet_alloc(&hd); + +} +#else +static void hpet_reserve_platform_timers(unsigned long id) { } +#endif + +/* + * Common hpet info + */ +static unsigned long hpet_period; + +static void hpet_set_mode(enum clock_event_mode mode, + struct clock_event_device *evt); +static void hpet_next_event(unsigned long delta, + struct clock_event_device *evt); + +/* + * The hpet clock event device + */ +static struct clock_event_device hpet_clockevent = { + .name = "hpet", + .capabilities = CLOCK_CAP_TICK | CLOCK_CAP_PROFILE | CLOCK_CAP_UPDATE + | CLOCK_CAP_NEXTEVT, + .set_mode = hpet_set_mode, + .set_next_event = hpet_next_event, + .shift = 32, +}; + +static void hpet_start_counter(void) +{ + unsigned long cfg = hpet_readl(HPET_CFG); + + cfg &= ~HPET_CFG_ENABLE; + hpet_writel(cfg, HPET_CFG); + hpet_writel(0, HPET_COUNTER); + hpet_writel(0, HPET_COUNTER + 4); + cfg |= HPET_CFG_ENABLE; + hpet_writel(cfg, HPET_CFG); +} + +static void hpet_enable_int(void) +{ + unsigned long cfg = hpet_readl(HPET_CFG); + + cfg |= HPET_CFG_LEGACY; + hpet_writel(cfg, HPET_CFG); + hpet_legacy_int_enabled = 1; +} + +static void hpet_set_mode(enum clock_event_mode mode, + struct clock_event_device *evt) +{ + unsigned long cfg, cmp, now; + uint64_t delta; + + switch(mode) { + case CLOCK_EVT_PERIODIC: + delta = ((uint64_t)(NSEC_PER_SEC/HZ)) * hpet_clockevent.mult; + delta >>= hpet_clockevent.shift; + now = hpet_readl(HPET_COUNTER); + cmp = now + (unsigned long) delta; + cfg = hpet_readl(HPET_T0_CFG); + cfg |= HPET_TN_ENABLE | HPET_TN_PERIODIC | + HPET_TN_SETVAL | HPET_TN_32BIT; + hpet_writel(cfg, HPET_T0_CFG); + /* + * The first write after writing TN_SETVAL to the + * config register sets the counter value, the second + * write sets the period. + */ + hpet_writel(cmp, HPET_T0_CMP); + udelay(1); + hpet_writel((unsigned long) delta, HPET_T0_CMP); + break; + + case CLOCK_EVT_ONESHOT: + cfg = hpet_readl(HPET_T0_CFG); + cfg &= ~HPET_TN_PERIODIC; + cfg |= HPET_TN_ENABLE | HPET_TN_32BIT; + hpet_writel(cfg, HPET_T0_CFG); + break; + + case CLOCK_EVT_SHUTDOWN: + cfg = hpet_readl(HPET_T0_CFG); + cfg &= ~HPET_TN_ENABLE; + hpet_writel(cfg, HPET_T0_CFG); + break; + } +} + +static void hpet_next_event(unsigned long delta, + struct clock_event_device *evt) +{ + unsigned long cnt; + do { + cnt = hpet_readl(HPET_COUNTER); + cnt += delta; + hpet_writel(cnt, HPET_T0_CMP); + } while ((long)(hpet_readl(HPET_COUNTER) - cnt ) > 0); +} + +/* + * Try to setup the HPET timer + */ +int __init hpet_enable(void) +{ + unsigned long id; + uint64_t hpet_freq; + + if (!is_hpet_capable()) + return 0; + + hpet_virt_address = ioremap_nocache(hpet_address, HPET_MMAP_SIZE); + + /* + * Read the period and check for a sane value: + */ + hpet_period = hpet_readl(HPET_PERIOD); + if (hpet_period < HPET_MIN_PERIOD || hpet_period > HPET_MAX_PERIOD) + goto out_nohpet; + + /* + * 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); + hpet_clockevent.mult = div_sc((unsigned long) hpet_freq, + NSEC_PER_SEC, 32); + /* Calculate the min / max delta */ + hpet_clockevent.max_delta_ns = clockevent_delta2ns(0x7FFFFFFF, + &hpet_clockevent); + hpet_clockevent.min_delta_ns = clockevent_delta2ns(0x30, + &hpet_clockevent); + + /* + * Read the HPET ID register to retrieve the IRQ routing + * information and the number of channels + */ + id = hpet_readl(HPET_ID); + +#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)) + goto out_nohpet; +#endif + + /* Start the counter */ + hpet_start_counter(); + + if (id & HPET_ID_LEGSUP) { + hpet_enable_int(); + hpet_reserve_platform_timers(id); + register_global_clockevent(&hpet_clockevent); + global_clock_event = &hpet_clockevent; + return 1; + } + return 0; + +out_nohpet: + iounmap(hpet_virt_address); + hpet_virt_address = NULL; + return 0; +} + +/* + * Clock source related code + */ static cycle_t read_hpet(void) { - return (cycle_t)readl(hpet_ptr); + return (cycle_t)hpet_readl(HPET_COUNTER); } static struct clocksource clocksource_hpet = { @@ -24,29 +280,17 @@ static struct clocksource clocksource_hp .rating = 250, .read = read_hpet, .mask = HPET_MASK, - .mult = 0, /* set below */ .shift = HPET_SHIFT, .is_continuous = 1, }; static int __init init_hpet_clocksource(void) { - unsigned long hpet_period; - void __iomem* hpet_base; u64 tmp; - int err; - if (!is_hpet_enabled()) + if (!hpet_virt_address) return -ENODEV; - /* calculate the hpet address: */ - hpet_base = - (void __iomem*)ioremap_nocache(hpet_address, HPET_MMAP_SIZE); - hpet_ptr = hpet_base + HPET_COUNTER; - - /* calculate the frequency: */ - hpet_period = readl(hpet_base + HPET_PERIOD); - /* * hpet period is in femto seconds per cycle * so we need to convert this to ns/cyc units @@ -62,11 +306,216 @@ static int __init init_hpet_clocksource( do_div(tmp, FSEC_PER_NSEC); clocksource_hpet.mult = (u32)tmp; - err = clocksource_register(&clocksource_hpet); - if (err) - iounmap(hpet_base); - - return err; + return clocksource_register(&clocksource_hpet); } module_init(init_hpet_clocksource); + +#ifdef CONFIG_HPET_EMULATE_RTC + +/* HPET in LegacyReplacement Mode eats up RTC interrupt line. When, HPET + * is enabled, we support RTC interrupt functionality in software. + * RTC has 3 kinds of interrupts: + * 1) Update Interrupt - generate an interrupt, every sec, when RTC clock + * is updated + * 2) Alarm Interrupt - generate an interrupt at a specific time of day + * 3) Periodic Interrupt - generate periodic interrupt, with frequencies + * 2Hz-8192Hz (2Hz-64Hz for non-root user) (all freqs in powers of 2) + * (1) and (2) above are implemented using polling at a frequency of + * 64 Hz. The exact frequency is a tradeoff between accuracy and interrupt + * overhead. (DEFAULT_RTC_INT_FREQ) + * For (3), we use interrupts at 64Hz or user specified periodic + * frequency, whichever is higher. + */ +#include +#include + +#define DEFAULT_RTC_INT_FREQ 64 +#define DEFAULT_RTC_SHIFT 6 +#define RTC_NUM_INTS 1 + +static unsigned long hpet_rtc_flags; +static unsigned long hpet_prev_update_sec; +static struct rtc_time hpet_alarm_time; +static unsigned long hpet_pie_count; +static unsigned long hpet_t1_cmp; +static unsigned long hpet_default_delta; +static unsigned long hpet_pie_delta; +static unsigned long hpet_pie_limit; + +/* + * Timer 1 for RTC emulation. We use one shot mode, as periodic mode + * is not supported by all HPET implementations for timer 1. + * + * hpet_rtc_timer_init() is called when the rtc is initialized. + */ +int hpet_rtc_timer_init(void) +{ + unsigned long cfg, cnt, delta, flags; + + if (!is_hpet_enabled()) + return 0; + + if (!hpet_default_delta) { + uint64_t clc; + + clc = (uint64_t) hpet_clockevent.mult * NSEC_PER_SEC; + clc >>= hpet_clockevent.shift + DEFAULT_RTC_SHIFT; + hpet_default_delta = (unsigned long) clc; + } + + if (!(hpet_rtc_flags & RTC_PIE) || hpet_pie_limit) + delta = hpet_default_delta; + else + delta = hpet_pie_delta; + + local_irq_save(flags); + + cnt = delta + hpet_readl(HPET_COUNTER); + hpet_writel(cnt, HPET_T1_CMP); + hpet_t1_cmp = cnt; + + cfg = hpet_readl(HPET_T1_CFG); + cfg &= ~HPET_TN_PERIODIC; + cfg |= HPET_TN_ENABLE | HPET_TN_32BIT; + hpet_writel(cfg, HPET_T1_CFG); + + local_irq_restore(flags); + + return 1; +} + +/* + * The functions below are called from rtc driver. + * Return 0 if HPET is not being used. + * Otherwise do the necessary changes and return 1. + */ +int hpet_mask_rtc_irq_bit(unsigned long bit_mask) +{ + if (!is_hpet_enabled()) + return 0; + + hpet_rtc_flags &= ~bit_mask; + return 1; +} + +int hpet_set_rtc_irq_bit(unsigned long bit_mask) +{ + unsigned long oldbits = hpet_rtc_flags; + + if (!is_hpet_enabled()) + return 0; + + hpet_rtc_flags |= bit_mask; + + if (!oldbits) + hpet_rtc_timer_init(); + + return 1; +} + +int hpet_set_alarm_time(unsigned char hrs, unsigned char min, + unsigned char sec) +{ + if (!is_hpet_enabled()) + return 0; + + hpet_alarm_time.tm_hour = hrs; + hpet_alarm_time.tm_min = min; + hpet_alarm_time.tm_sec = sec; + + return 1; +} + +int hpet_set_periodic_freq(unsigned long freq) +{ + uint64_t clc; + + if (!is_hpet_enabled()) + return 0; + + if (freq <= DEFAULT_RTC_INT_FREQ) + hpet_pie_limit = DEFAULT_RTC_INT_FREQ / freq; + else { + clc = (uint64_t) hpet_clockevent.mult * NSEC_PER_SEC; + do_div(clc, freq); + clc >>= hpet_clockevent.shift; + hpet_pie_delta = (unsigned long) clc; + } + return 1; +} + +int hpet_rtc_dropped_irq(void) +{ + return is_hpet_enabled(); +} + +static void hpet_rtc_timer_reinit(void) +{ + unsigned long cfg, 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 (!(hpet_rtc_flags & RTC_PIE) || hpet_pie_limit) + delta = hpet_default_delta; + else + delta = hpet_pie_delta; + + /* + * Increment the comparator value until we are ahead of the + * current count. + */ + do { + hpet_t1_cmp += delta; + hpet_writel(hpet_t1_cmp, HPET_T1_CMP); + lost_ints++; + } while ((long)(hpet_readl(HPET_COUNTER) - hpet_t1_cmp) > 0); + + if (lost_ints) { + if (hpet_rtc_flags & RTC_PIE) + hpet_pie_count += lost_ints; + printk(KERN_WARNING "rtc: lost %d interrupts\n", lost_ints); + } +} + +irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id) +{ + struct rtc_time curr_time; + unsigned long rtc_int_flag = 0; + + hpet_rtc_timer_reinit(); + + if (hpet_rtc_flags & (RTC_UIE | RTC_AIE)) + rtc_get_rtc_time(&curr_time); + + if (hpet_rtc_flags & RTC_UIE && + curr_time.tm_sec != hpet_prev_update_sec) { + rtc_int_flag = RTC_UF; + hpet_prev_update_sec = curr_time.tm_sec; + } + + if (hpet_rtc_flags & RTC_PIE && + ++hpet_pie_count >= hpet_pie_limit) { + rtc_int_flag |= RTC_PF; + hpet_pie_count = 0; + } + + if (hpet_rtc_flags & RTC_PIE && + (curr_time.tm_sec == hpet_alarm_time.tm_sec) && + (curr_time.tm_min == hpet_alarm_time.tm_min) && + (curr_time.tm_hour == hpet_alarm_time.tm_hour)) + rtc_int_flag |= RTC_AF; + + if (rtc_int_flag) { + rtc_int_flag |= (RTC_IRQF | (RTC_NUM_INTS << 8)); + rtc_interrupt(rtc_int_flag, dev_id); + } + return IRQ_HANDLED; +} +#endif diff -puN arch/i386/kernel/i8259.c~clockevents-i386-hpet-driver arch/i386/kernel/i8259.c --- a/arch/i386/kernel/i8259.c~clockevents-i386-hpet-driver +++ a/arch/i386/kernel/i8259.c @@ -410,12 +410,6 @@ void __init native_init_IRQ(void) intr_init_hook(); /* - * Set the clock to HZ Hz, we already have a valid - * vector now: - */ - setup_pit_timer(); - - /* * External FPU? Set up irq13 if so, for * original braindamaged IBM FERR coupling. */ diff -puN arch/i386/kernel/time.c~clockevents-i386-hpet-driver arch/i386/kernel/time.c --- a/arch/i386/kernel/time.c~clockevents-i386-hpet-driver +++ a/arch/i386/kernel/time.c @@ -260,30 +260,16 @@ void notify_arch_cmos_timer(void) mod_timer(&sync_cmos_timer, jiffies + 1); } -#ifdef CONFIG_HPET_TIMER extern void (*late_time_init)(void); /* Duplicate of time_init() below, with hpet_enable part added */ static void __init hpet_time_init(void) { - if ((hpet_enable() >= 0) && hpet_use_timer) { - printk("Using HPET for base-timer\n"); - } - + if (!hpet_enable()) + setup_pit_timer(); do_time_init(); } -#endif void __init time_init(void) { -#ifdef CONFIG_HPET_TIMER - if (is_hpet_capable()) { - /* - * HPET initialization needs to do memory-mapped io. So, let - * us do a late initialization after mem_init(). - */ - late_time_init = hpet_time_init; - return; - } -#endif - do_time_init(); + late_time_init = hpet_time_init; } diff -puN arch/i386/kernel/time_hpet.c~clockevents-i386-hpet-driver /dev/null --- a/arch/i386/kernel/time_hpet.c +++ /dev/null @@ -1,492 +0,0 @@ -/* - * linux/arch/i386/kernel/time_hpet.c - * This code largely copied from arch/x86_64/kernel/time.c - * See that file for credits. - * - * 2003-06-30 Venkatesh Pallipadi - Additional changes for HPET support - */ - -#include -#include -#include -#include -#include -#include - -#include -#include -#include - -#include - -#include -#include - -static unsigned long hpet_period; /* fsecs / HPET clock */ -unsigned long hpet_tick; /* hpet clks count per tick */ -unsigned long hpet_address; /* hpet memory map physical address */ -int hpet_use_timer; - -static int use_hpet; /* can be used for runtime check of hpet */ -static int boot_hpet_disable; /* boottime override for HPET timer */ -static void __iomem * hpet_virt_address; /* hpet kernel virtual address */ - -#define FSEC_TO_USEC (1000000000UL) - -int hpet_readl(unsigned long a) -{ - return readl(hpet_virt_address + a); -} - -static void hpet_writel(unsigned long d, unsigned long a) -{ - writel(d, hpet_virt_address + a); -} - -#ifdef CONFIG_X86_LOCAL_APIC -/* - * HPET counters dont wrap around on every tick. They just change the - * comparator value and continue. Next tick can be caught by checking - * for a change in the comparator value. Used in apic.c. - */ -static void __devinit wait_hpet_tick(void) -{ - unsigned int start_cmp_val, end_cmp_val; - - start_cmp_val = hpet_readl(HPET_T0_CMP); - do { - end_cmp_val = hpet_readl(HPET_T0_CMP); - } while (start_cmp_val == end_cmp_val); -} -#endif - -static int hpet_timer_stop_set_go(unsigned long tick) -{ - unsigned int cfg; - - /* - * Stop the timers and reset the main counter. - */ - cfg = hpet_readl(HPET_CFG); - cfg &= ~HPET_CFG_ENABLE; - hpet_writel(cfg, HPET_CFG); - hpet_writel(0, HPET_COUNTER); - hpet_writel(0, HPET_COUNTER + 4); - - if (hpet_use_timer) { - /* - * Set up timer 0, as periodic with first interrupt to happen at - * hpet_tick, and period also hpet_tick. - */ - cfg = hpet_readl(HPET_T0_CFG); - cfg |= HPET_TN_ENABLE | HPET_TN_PERIODIC | - HPET_TN_SETVAL | HPET_TN_32BIT; - hpet_writel(cfg, HPET_T0_CFG); - - /* - * The first write after writing TN_SETVAL to the config register sets - * the counter value, the second write sets the threshold. - */ - hpet_writel(tick, HPET_T0_CMP); - hpet_writel(tick, HPET_T0_CMP); - } - /* - * Go! - */ - cfg = hpet_readl(HPET_CFG); - if (hpet_use_timer) - cfg |= HPET_CFG_LEGACY; - cfg |= HPET_CFG_ENABLE; - hpet_writel(cfg, HPET_CFG); - - return 0; -} - -/* - * Check whether HPET was found by ACPI boot parse. If yes setup HPET - * counter 0 for kernel base timer. - */ -int __init hpet_enable(void) -{ - unsigned int id; - unsigned long tick_fsec_low, tick_fsec_high; /* tick in femto sec */ - unsigned long hpet_tick_rem; - - if (boot_hpet_disable) - return -1; - - if (!hpet_address) { - return -1; - } - hpet_virt_address = ioremap_nocache(hpet_address, HPET_MMAP_SIZE); - /* - * Read the period, compute tick and quotient. - */ - id = hpet_readl(HPET_ID); - - /* - * We are checking for value '1' or more in number field if - * CONFIG_HPET_EMULATE_RTC is set because we will need an - * additional timer for RTC emulation. - * However, we can do with one timer otherwise using the - * the single HPET timer for system time. - */ -#ifdef CONFIG_HPET_EMULATE_RTC - if (!(id & HPET_ID_NUMBER)) { - iounmap(hpet_virt_address); - hpet_virt_address = NULL; - return -1; - } -#endif - - - hpet_period = hpet_readl(HPET_PERIOD); - if ((hpet_period < HPET_MIN_PERIOD) || (hpet_period > HPET_MAX_PERIOD)) { - iounmap(hpet_virt_address); - hpet_virt_address = NULL; - return -1; - } - - /* - * 64 bit math - * First changing tick into fsec - * Then 64 bit div to find number of hpet clk per tick - */ - ASM_MUL64_REG(tick_fsec_low, tick_fsec_high, - KERNEL_TICK_USEC, FSEC_TO_USEC); - ASM_DIV64_REG(hpet_tick, hpet_tick_rem, - hpet_period, tick_fsec_low, tick_fsec_high); - - if (hpet_tick_rem > (hpet_period >> 1)) - hpet_tick++; /* rounding the result */ - - hpet_use_timer = id & HPET_ID_LEGSUP; - - if (hpet_timer_stop_set_go(hpet_tick)) { - iounmap(hpet_virt_address); - hpet_virt_address = NULL; - return -1; - } - - use_hpet = 1; - -#ifdef CONFIG_HPET - { - struct hpet_data hd; - unsigned int ntimer; - - memset(&hd, 0, sizeof (hd)); - - ntimer = hpet_readl(HPET_ID); - ntimer = (ntimer & HPET_ID_NUMBER) >> HPET_ID_NUMBER_SHIFT; - ntimer++; - - /* - * Register with driver. - * Timer0 and Timer1 is used by platform. - */ - hd.hd_phys_address = hpet_address; - hd.hd_address = hpet_virt_address; - hd.hd_nirqs = ntimer; - hd.hd_flags = HPET_DATA_PLATFORM; - hpet_reserve_timer(&hd, 0); -#ifdef CONFIG_HPET_EMULATE_RTC - hpet_reserve_timer(&hd, 1); -#endif - hd.hd_irq[0] = HPET_LEGACY_8254; - hd.hd_irq[1] = HPET_LEGACY_RTC; - if (ntimer > 2) { - struct hpet __iomem *hpet; - struct hpet_timer __iomem *timer; - int i; - - hpet = hpet_virt_address; - - for (i = 2, timer = &hpet->hpet_timers[2]; i < ntimer; - timer++, i++) - hd.hd_irq[i] = (timer->hpet_config & - Tn_INT_ROUTE_CNF_MASK) >> - Tn_INT_ROUTE_CNF_SHIFT; - - } - - hpet_alloc(&hd); - } -#endif - -#ifdef CONFIG_X86_LOCAL_APIC - if (hpet_use_timer) - wait_timer_tick = wait_hpet_tick; -#endif - return 0; -} - -int is_hpet_enabled(void) -{ - return use_hpet; -} - -int is_hpet_capable(void) -{ - if (!boot_hpet_disable && hpet_address) - return 1; - return 0; -} - -static int __init hpet_setup(char* str) -{ - if (str) { - if (!strncmp("disable", str, 7)) - boot_hpet_disable = 1; - } - return 1; -} - -__setup("hpet=", hpet_setup); - -#ifdef CONFIG_HPET_EMULATE_RTC -/* HPET in LegacyReplacement Mode eats up RTC interrupt line. When, HPET - * is enabled, we support RTC interrupt functionality in software. - * RTC has 3 kinds of interrupts: - * 1) Update Interrupt - generate an interrupt, every sec, when RTC clock - * is updated - * 2) Alarm Interrupt - generate an interrupt at a specific time of day - * 3) Periodic Interrupt - generate periodic interrupt, with frequencies - * 2Hz-8192Hz (2Hz-64Hz for non-root user) (all freqs in powers of 2) - * (1) and (2) above are implemented using polling at a frequency of - * 64 Hz. The exact frequency is a tradeoff between accuracy and interrupt - * overhead. (DEFAULT_RTC_INT_FREQ) - * For (3), we use interrupts at 64Hz or user specified periodic - * frequency, whichever is higher. - */ -#include -#include - -#define DEFAULT_RTC_INT_FREQ 64 -#define RTC_NUM_INTS 1 - -static unsigned long UIE_on; -static unsigned long prev_update_sec; - -static unsigned long AIE_on; -static struct rtc_time alarm_time; - -static unsigned long PIE_on; -static unsigned long PIE_freq = DEFAULT_RTC_INT_FREQ; -static unsigned long PIE_count; - -static unsigned long hpet_rtc_int_freq; /* RTC interrupt frequency */ -static unsigned int hpet_t1_cmp; /* cached comparator register */ - -/* - * Timer 1 for RTC, we do not use periodic interrupt feature, - * even if HPET supports periodic interrupts on Timer 1. - * The reason being, to set up a periodic interrupt in HPET, we need to - * stop the main counter. And if we do that everytime someone diables/enables - * RTC, we will have adverse effect on main kernel timer running on Timer 0. - * So, for the time being, simulate the periodic interrupt in software. - * - * hpet_rtc_timer_init() is called for the first time and during subsequent - * interuppts reinit happens through hpet_rtc_timer_reinit(). - */ -int hpet_rtc_timer_init(void) -{ - unsigned int cfg, cnt; - unsigned long flags; - - if (!is_hpet_enabled()) - return 0; - /* - * Set the counter 1 and enable the interrupts. - */ - if (PIE_on && (PIE_freq > DEFAULT_RTC_INT_FREQ)) - hpet_rtc_int_freq = PIE_freq; - else - hpet_rtc_int_freq = DEFAULT_RTC_INT_FREQ; - - local_irq_save(flags); - - cnt = hpet_readl(HPET_COUNTER); - cnt += ((hpet_tick*HZ)/hpet_rtc_int_freq); - hpet_writel(cnt, HPET_T1_CMP); - hpet_t1_cmp = cnt; - - cfg = hpet_readl(HPET_T1_CFG); - cfg &= ~HPET_TN_PERIODIC; - cfg |= HPET_TN_ENABLE | HPET_TN_32BIT; - hpet_writel(cfg, HPET_T1_CFG); - - local_irq_restore(flags); - - return 1; -} - -static void hpet_rtc_timer_reinit(void) -{ - unsigned int cfg, cnt, ticks_per_int, lost_ints; - - if (unlikely(!(PIE_on | AIE_on | UIE_on))) { - cfg = hpet_readl(HPET_T1_CFG); - cfg &= ~HPET_TN_ENABLE; - hpet_writel(cfg, HPET_T1_CFG); - return; - } - - if (PIE_on && (PIE_freq > DEFAULT_RTC_INT_FREQ)) - hpet_rtc_int_freq = PIE_freq; - else - hpet_rtc_int_freq = DEFAULT_RTC_INT_FREQ; - - /* It is more accurate to use the comparator value than current count.*/ - ticks_per_int = hpet_tick * HZ / hpet_rtc_int_freq; - hpet_t1_cmp += ticks_per_int; - hpet_writel(hpet_t1_cmp, HPET_T1_CMP); - - /* - * If the interrupt handler was delayed too long, the write above tries - * to schedule the next interrupt in the past and the hardware would - * not interrupt until the counter had wrapped around. - * So we have to check that the comparator wasn't set to a past time. - */ - cnt = hpet_readl(HPET_COUNTER); - if (unlikely((int)(cnt - hpet_t1_cmp) > 0)) { - lost_ints = (cnt - hpet_t1_cmp) / ticks_per_int + 1; - /* Make sure that, even with the time needed to execute - * this code, the next scheduled interrupt has been moved - * back to the future: */ - lost_ints++; - - hpet_t1_cmp += lost_ints * ticks_per_int; - hpet_writel(hpet_t1_cmp, HPET_T1_CMP); - - if (PIE_on) - PIE_count += lost_ints; - - printk(KERN_WARNING "rtc: lost some interrupts at %ldHz.\n", - hpet_rtc_int_freq); - } -} - -/* - * The functions below are called from rtc driver. - * Return 0 if HPET is not being used. - * Otherwise do the necessary changes and return 1. - */ -int hpet_mask_rtc_irq_bit(unsigned long bit_mask) -{ - if (!is_hpet_enabled()) - return 0; - - if (bit_mask & RTC_UIE) - UIE_on = 0; - if (bit_mask & RTC_PIE) - PIE_on = 0; - if (bit_mask & RTC_AIE) - AIE_on = 0; - - return 1; -} - -int hpet_set_rtc_irq_bit(unsigned long bit_mask) -{ - int timer_init_reqd = 0; - - if (!is_hpet_enabled()) - return 0; - - if (!(PIE_on | AIE_on | UIE_on)) - timer_init_reqd = 1; - - if (bit_mask & RTC_UIE) { - UIE_on = 1; - } - if (bit_mask & RTC_PIE) { - PIE_on = 1; - PIE_count = 0; - } - if (bit_mask & RTC_AIE) { - AIE_on = 1; - } - - if (timer_init_reqd) - hpet_rtc_timer_init(); - - return 1; -} - -int hpet_set_alarm_time(unsigned char hrs, unsigned char min, unsigned char sec) -{ - if (!is_hpet_enabled()) - return 0; - - alarm_time.tm_hour = hrs; - alarm_time.tm_min = min; - alarm_time.tm_sec = sec; - - return 1; -} - -int hpet_set_periodic_freq(unsigned long freq) -{ - if (!is_hpet_enabled()) - return 0; - - PIE_freq = freq; - PIE_count = 0; - - return 1; -} - -int hpet_rtc_dropped_irq(void) -{ - if (!is_hpet_enabled()) - return 0; - - return 1; -} - -irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id) -{ - struct rtc_time curr_time; - unsigned long rtc_int_flag = 0; - int call_rtc_interrupt = 0; - - hpet_rtc_timer_reinit(); - - if (UIE_on | AIE_on) { - rtc_get_rtc_time(&curr_time); - } - if (UIE_on) { - if (curr_time.tm_sec != prev_update_sec) { - /* Set update int info, call real rtc int routine */ - call_rtc_interrupt = 1; - rtc_int_flag = RTC_UF; - prev_update_sec = curr_time.tm_sec; - } - } - if (PIE_on) { - PIE_count++; - if (PIE_count >= hpet_rtc_int_freq/PIE_freq) { - /* Set periodic int info, call real rtc int routine */ - call_rtc_interrupt = 1; - rtc_int_flag |= RTC_PF; - PIE_count = 0; - } - } - if (AIE_on) { - if ((curr_time.tm_sec == alarm_time.tm_sec) && - (curr_time.tm_min == alarm_time.tm_min) && - (curr_time.tm_hour == alarm_time.tm_hour)) { - /* Set alarm int info, call real rtc int routine */ - call_rtc_interrupt = 1; - rtc_int_flag |= RTC_AF; - } - } - if (call_rtc_interrupt) { - rtc_int_flag |= (RTC_IRQF | (RTC_NUM_INTS << 8)); - rtc_interrupt(rtc_int_flag, dev_id); - } - return IRQ_HANDLED; -} -#endif - diff -puN include/asm-i386/hpet.h~clockevents-i386-hpet-driver include/asm-i386/hpet.h --- a/include/asm-i386/hpet.h~clockevents-i386-hpet-driver +++ a/include/asm-i386/hpet.h @@ -90,15 +90,19 @@ #define HPET_MIN_PERIOD (100000UL) #define HPET_TICK_RATE (HZ * 100000UL) -extern unsigned long hpet_tick; /* hpet clks count per tick */ extern unsigned long hpet_address; /* hpet memory map physical address */ -extern int hpet_use_timer; +extern int is_hpet_enabled(void); +#ifdef CONFIG_X86_64 +extern unsigned long hpet_tick; /* hpet clks count per tick */ +extern int hpet_use_timer; extern int hpet_rtc_timer_init(void); extern int hpet_enable(void); -extern int is_hpet_enabled(void); extern int is_hpet_capable(void); extern int hpet_readl(unsigned long a); +#else +extern int hpet_enable(void); +#endif #ifdef CONFIG_HPET_EMULATE_RTC extern int hpet_mask_rtc_irq_bit(unsigned long bit_mask); @@ -109,5 +113,10 @@ extern int hpet_rtc_dropped_irq(void); extern int hpet_rtc_timer_init(void); extern irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id); #endif /* CONFIG_HPET_EMULATE_RTC */ + +#else + +static inline int hpet_enable(void) { return 0; } + #endif /* CONFIG_HPET_TIMER */ #endif /* _I386_HPET_H */ _