[PATCH] clockevents: i386 drivers

Add clockevent drivers for i386: lapic (local) and PIT/HPET (global).  Update
the timer IRQ to call into the PIT/HPET driver's event handler and the
lapic-timer IRQ to call into the lapic clockevent driver.  The assignement of
timer functionality is delegated to the core framework code and replaces the
compile and runtime evalution in do_timer_interrupt_hook()

Use the clockevents broadcast support and implement the lapic_broadcast
function for ACPI.

No changes to existing functionality.

[ kdump fix from Vivek Goyal <vgoyal@in.ibm.com> ]
[ fixes based on review feedback from Arjan van de Ven <arjan@infradead.org> ]
Cleanups-from: Adrian Bunk <bunk@stusta.de>
Build-fixes-from: Andrew Morton <akpm@osdl.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

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 1e4702dfcd0..00000000000
--- 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
-