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Diffstat (limited to 'arch/i386/kernel/time_hpet.c')
-rw-r--r--arch/i386/kernel/time_hpet.c497
1 files changed, 0 insertions, 497 deletions
diff --git a/arch/i386/kernel/time_hpet.c b/arch/i386/kernel/time_hpet.c
deleted file mode 100644
index 1e4702dfcd01..000000000000
--- a/arch/i386/kernel/time_hpet.c
+++ /dev/null
@@ -1,497 +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 <linux/errno.h>
-#include <linux/kernel.h>
-#include <linux/param.h>
-#include <linux/string.h>
-#include <linux/init.h>
-#include <linux/smp.h>
-
-#include <asm/timer.h>
-#include <asm/fixmap.h>
-#include <asm/apic.h>
-
-#include <linux/timex.h>
-
-#include <asm/hpet.h>
-#include <linux/hpet.h>
-
-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 hpet_reenable(void)
-{
- return hpet_timer_stop_set_go(hpet_tick);
-}
-
-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 <linux/mc146818rtc.h>
-#include <linux/rtc.h>
-
-#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
-