[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>

6 files changed, 41 insertions, 101 deletions

diff --git a/include/asm-i386/apic.h b/include/asm-i386/apic.h
index ccf64fa7b93..a595fe05427 100644
--- a/include/asm-i386/apic.h
+++ b/include/asm-i386/apic.h
@@ -113,14 +113,9 @@ extern void smp_local_timer_interrupt (void);
 extern void setup_boot_APIC_clock (void);
 extern void setup_secondary_APIC_clock (void);
 extern int APIC_init_uniprocessor (void);
-extern void disable_APIC_timer(void);
-extern void enable_APIC_timer(void);
 
 extern void enable_NMI_through_LVT0 (void * dummy);
 
-void smp_send_timer_broadcast_ipi(void);
-void switch_APIC_timer_to_ipi(void *cpumask);
-void switch_ipi_to_APIC_timer(void *cpumask);
 #define ARCH_APICTIMER_STOPS_ON_C3	1
 
 extern int timer_over_8254;
diff --git a/include/asm-i386/hpet.h b/include/asm-i386/hpet.h
index e47be9a56cc..fc03cf9de5c 100644
--- a/include/asm-i386/hpet.h
+++ b/include/asm-i386/hpet.h
@@ -90,16 +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 hpet_reenable(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);
@@ -110,5 +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 */
diff --git a/include/asm-i386/i8253.h b/include/asm-i386/i8253.h
index 015d8df0769..6cb0dd4dcdd 100644
--- a/include/asm-i386/i8253.h
+++ b/include/asm-i386/i8253.h
@@ -1,6 +1,21 @@
 #ifndef __ASM_I8253_H__
 #define __ASM_I8253_H__
 
+#include <linux/clockchips.h>
+
 extern spinlock_t i8253_lock;
 
+extern struct clock_event_device *global_clock_event;
+
+/**
+ * pit_interrupt_hook - hook into timer tick
+ * @regs:	standard registers from interrupt
+ *
+ * Call the global clock event handler.
+ **/
+static inline void pit_interrupt_hook(void)
+{
+	global_clock_event->event_handler(global_clock_event);
+}
+
 #endif	/* __ASM_I8253_H__ */
diff --git a/include/asm-i386/mach-default/do_timer.h b/include/asm-i386/mach-default/do_timer.h
index 7d606e3364a..56e5689863a 100644
--- a/include/asm-i386/mach-default/do_timer.h
+++ b/include/asm-i386/mach-default/do_timer.h
@@ -1,86 +1,16 @@
 /* defines for inline arch setup functions */
+#include <linux/clockchips.h>
 
-#include <asm/apic.h>
 #include <asm/i8259.h>
+#include <asm/i8253.h>
 
 /**
  * do_timer_interrupt_hook - hook into timer tick
- * @regs:	standard registers from interrupt
  *
- * Description:
- *	This hook is called immediately after the timer interrupt is ack'd.
- *	It's primary purpose is to allow architectures that don't possess
- *	individual per CPU clocks (like the CPU APICs supply) to broadcast the
- *	timer interrupt as a means of triggering reschedules etc.
+ * Call the pit clock event handler. see asm/i8253.h
  **/
 
 static inline void do_timer_interrupt_hook(void)
 {
-	do_timer(1);
-#ifndef CONFIG_SMP
-	update_process_times(user_mode_vm(get_irq_regs()));
-#endif
-/*
- * In the SMP case we use the local APIC timer interrupt to do the
- * profiling, except when we simulate SMP mode on a uniprocessor
- * system, in that case we have to call the local interrupt handler.
- */
-#ifndef CONFIG_X86_LOCAL_APIC
-	profile_tick(CPU_PROFILING);
-#else
-	if (!using_apic_timer)
-		smp_local_timer_interrupt();
-#endif
-}
-
-
-/* you can safely undefine this if you don't have the Neptune chipset */
-
-#define BUGGY_NEPTUN_TIMER
-
-/**
- * do_timer_overflow - process a detected timer overflow condition
- * @count:	hardware timer interrupt count on overflow
- *
- * Description:
- *	This call is invoked when the jiffies count has not incremented but
- *	the hardware timer interrupt has.  It means that a timer tick interrupt
- *	came along while the previous one was pending, thus a tick was missed
- **/
-static inline int do_timer_overflow(int count)
-{
-	int i;
-
-	spin_lock(&i8259A_lock);
-	/*
-	 * This is tricky when I/O APICs are used;
-	 * see do_timer_interrupt().
-	 */
-	i = inb(0x20);
-	spin_unlock(&i8259A_lock);
-	
-	/* assumption about timer being IRQ0 */
-	if (i & 0x01) {
-		/*
-		 * We cannot detect lost timer interrupts ... 
-		 * well, that's why we call them lost, don't we? :)
-		 * [hmm, on the Pentium and Alpha we can ... sort of]
-		 */
-		count -= LATCH;
-	} else {
-#ifdef BUGGY_NEPTUN_TIMER
-		/*
-		 * for the Neptun bug we know that the 'latch'
-		 * command doesn't latch the high and low value
-		 * of the counter atomically. Thus we have to 
-		 * substract 256 from the counter 
-		 * ... funny, isnt it? :)
-		 */
-		
-		count -= 256;
-#else
-		printk("do_slow_gettimeoffset(): hardware timer problem?\n");
-#endif
-	}
-	return count;
+	pit_interrupt_hook();
 }
diff --git a/include/asm-i386/mach-voyager/do_timer.h b/include/asm-i386/mach-voyager/do_timer.h
index 04e69c104a7..60f9dcc15d5 100644
--- a/include/asm-i386/mach-voyager/do_timer.h
+++ b/include/asm-i386/mach-voyager/do_timer.h
@@ -1,25 +1,18 @@
 /* defines for inline arch setup functions */
+#include <linux/clockchips.h>
+
 #include <asm/voyager.h>
+#include <asm/i8253.h>
 
+/**
+ * do_timer_interrupt_hook - hook into timer tick
+ * @regs:     standard registers from interrupt
+ *
+ * Call the pit clock event handler. see asm/i8253.h
+ **/
 static inline void do_timer_interrupt_hook(void)
 {
-	do_timer(1);
-#ifndef CONFIG_SMP
-	update_process_times(user_mode_vm(irq_regs));
-#endif
-
+	pit_interrupt_hook();
 	voyager_timer_interrupt();
 }
 
-static inline int do_timer_overflow(int count)
-{
-	/* can't read the ISR, just assume 1 tick
-	   overflow */
-	if(count > LATCH || count < 0) {
-		printk(KERN_ERR "VOYAGER PROBLEM: count is %d, latch is %d\n", count, LATCH);
-		count = LATCH;
-	}
-	count -= LATCH;
-
-	return count;
-}
diff --git a/include/asm-i386/mpspec.h b/include/asm-i386/mpspec.h
index 770bf6da8c3..f21349399d1 100644
--- a/include/asm-i386/mpspec.h
+++ b/include/asm-i386/mpspec.h
@@ -23,7 +23,6 @@ extern struct mpc_config_intsrc mp_irqs [MAX_IRQ_SOURCES];
 extern int mpc_default_type;
 extern unsigned long mp_lapic_addr;
 extern int pic_mode;
-extern int using_apic_timer;
 
 #ifdef CONFIG_ACPI
 extern void mp_register_lapic (u8 id, u8 enabled);