diff -urNp x-ref/Documentation/Configure.help x/Documentation/Configure.help
--- x-ref/Documentation/Configure.help	Mon Sep 30 03:47:30 2002
+++ x/Documentation/Configure.help	Mon Sep 30 03:47:32 2002
@@ -252,6 +252,14 @@ CONFIG_X86_NUMAQ
   You will need a new lynxer.elf file to flash your firmware with - send
   email to Martin.Bligh@us.ibm.com
 
+IBM x440 Summit support
+CONFIG_X86_CYCLONE
+  This option enables support for the IBM x440 and related multi-CEC 
+  systems based on the Summit chipset. This options allows you to pass
+  "cyclone" as a boot option to make use of a performance counter on 
+  the Cyclone chipset for calculating do_gettimeofday, greatly 
+  improving performance when compared to the PIT based method. 
+
 IO-APIC support on uniprocessors
 CONFIG_X86_UP_IOAPIC
   An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
diff -urNp x-ref/arch/i386/config.in x/arch/i386/config.in
--- x-ref/arch/i386/config.in	Mon Sep 30 03:47:31 2002
+++ x/arch/i386/config.in	Mon Sep 30 03:47:32 2002
@@ -241,8 +241,9 @@ else
    fi
 fi
 
+bool 'IBM x440 Gettimeofday Cyclone Timer support' CONFIG_X86_CYCLONE
 bool 'Unsynced TSC support' CONFIG_X86_TSC_DISABLE
-if [ "$CONFIG_X86_TSC_DISABLE" != "y" -a "$CONFIG_X86_HAS_TSC" = "y" ]; then
+if [ "$CONFIG_X86_TSC_DISABLE" != "y" -a "$CONFIG_X86_HAS_TSC" = "y" -a "$CONFIG_X86_CYCLONE" != "y" ]; then
    define_bool CONFIG_X86_TSC y
 fi
 
diff -urNp x-ref/arch/i386/kernel/setup.c x/arch/i386/kernel/setup.c
--- x-ref/arch/i386/kernel/setup.c	Mon Sep 30 03:47:30 2002
+++ x/arch/i386/kernel/setup.c	Mon Sep 30 03:47:32 2002
@@ -1173,7 +1173,7 @@ __setup("cachesize=", cachesize_setup);
 
 
 #ifndef CONFIG_X86_TSC
-static int tsc_disable __initdata = 0;
+int tsc_disable __initdata = 0;
 
 static int __init notsc_setup(char *str)
 {
diff -urNp x-ref/arch/i386/kernel/time.c x/arch/i386/kernel/time.c
--- x-ref/arch/i386/kernel/time.c	Thu Sep 26 04:13:59 2002
+++ x/arch/i386/kernel/time.c	Mon Sep 30 03:47:45 2002
@@ -121,6 +121,138 @@ EXPORT_SYMBOL(i8253_lock);
 
 extern spinlock_t i8259A_lock;
 
+#ifdef CONFIG_X86_CYCLONE
+
+#define CYCLONE_CBAR_ADDR 0xFEB00CD0
+#define CYCLONE_PMCC_OFFSET 0x51A0
+#define CYCLONE_MPMC_OFFSET 0x51D0
+#define CYCLONE_MPCS_OFFSET 0x51A8
+#define CYCLONE_TIMER_FREQ 100000000
+
+static int use_cyclone __initdata = 0;
+extern int tsc_disable;
+/*XXX - should autodetect*/
+static int __init cyclone_setup(char *str) 
+{
+	tsc_disable = 1;
+	use_cyclone = 1;
+	return 1;
+}
+__setup("cyclone", cyclone_setup);
+
+
+static u32* cyclone_timer;	/*Cyclone MPMC0 register*/
+static u32 last_cyclone_timer;
+
+static inline void mark_timeoffset_cyclone(void)
+{
+	int count;
+
+	/*quickly read the cyclone timer*/
+	if(cyclone_timer)
+		last_cyclone_timer = cyclone_timer[0];
+
+	/*calculate delay_at_last_interrupt*/
+	spin_lock(&i8253_lock);
+	outb_p(0x00, 0x43);     /* latch the count ASAP */
+
+	count = inb_p(0x40);    /* read the latched count */
+	count |= inb(0x40) << 8;
+	spin_unlock(&i8253_lock);
+
+	count = ((LATCH-1) - count) * TICK_SIZE;
+	delay_at_last_interrupt = (count + LATCH/2) / LATCH;
+}
+
+static unsigned long do_gettimeoffset_cyclone(void)
+{
+	u32 offset;
+
+	if(!cyclone_timer)
+		return delay_at_last_interrupt;
+
+	/* Read the cyclone timer */
+	offset = cyclone_timer[0];
+
+	/* .. relative to previous jiffy*/
+	offset = offset - last_cyclone_timer;
+
+	/*convert cyclone ticks to microseconds*/	
+	offset = offset/100;	/*XXX slow, can we speed this up?*/
+
+	/* our adjusted time offset in microseconds */
+	return delay_at_last_interrupt + offset;
+}
+
+static void init_cyclone_clock(void)
+{
+	u32* reg;	
+	u32 base;	/*saved cyclone base address*/
+	u32 pageaddr; /*page that contains cyclone_timer register*/
+	u32 offset;	/*offset from pageaddr to cyclone_timer register*/
+
+	printk(KERN_INFO "Summit chipset: Starting Cyclone Clock.\n");
+
+	/*find base address*/
+	pageaddr = (CYCLONE_CBAR_ADDR)&PAGE_MASK;
+	offset = (CYCLONE_CBAR_ADDR)&(~PAGE_MASK);
+	set_fixmap_nocache(FIX_CYCLONE_TIMER, pageaddr);
+	reg = (u32*)(fix_to_virt(FIX_CYCLONE_TIMER) + offset);
+	if(!reg){
+		printk(KERN_ERR "Summit chipset: Could not find valid CBAR register.\n");
+		return;
+	}
+	base = *reg;	
+	if(!base){
+		printk(KERN_ERR "Summit chipset: Could not find valid CBAR value.\n");
+		return;
+	}
+	
+	/*setup PMCC*/
+	pageaddr = (base + CYCLONE_PMCC_OFFSET)&PAGE_MASK;
+	offset = (base + CYCLONE_PMCC_OFFSET)&(~PAGE_MASK);
+	set_fixmap_nocache(FIX_CYCLONE_TIMER, pageaddr);
+	reg = (u32*)(fix_to_virt(FIX_CYCLONE_TIMER) + offset);
+	if(!reg){
+		printk(KERN_ERR "Summit chipset: Could not find valid PMCC register.\n");
+		return;
+	}
+	reg[0] = 0x00000001;
+
+	/*setup MPCS*/
+	pageaddr = (base + CYCLONE_MPCS_OFFSET)&PAGE_MASK;
+	offset = (base + CYCLONE_MPCS_OFFSET)&(~PAGE_MASK);
+	set_fixmap_nocache(FIX_CYCLONE_TIMER, pageaddr);
+	reg = (u32*)(fix_to_virt(FIX_CYCLONE_TIMER) + offset);
+	if(!reg){
+		printk(KERN_ERR "Summit chipset: Could not find valid MPCS register.\n");
+		return;
+	}
+	reg[0] = 0x00000001;
+
+	/*map in cyclone_timer*/
+	pageaddr = (base + CYCLONE_MPMC_OFFSET)&PAGE_MASK;
+	offset = (base + CYCLONE_MPMC_OFFSET)&(~PAGE_MASK);
+	set_fixmap_nocache(FIX_CYCLONE_TIMER, pageaddr);
+	cyclone_timer = (u32*)(fix_to_virt(FIX_CYCLONE_TIMER) + offset);
+	if(!cyclone_timer){
+		printk(KERN_ERR "Summit chipset: Could not find valid MPMC register.\n");
+		return;
+	}
+
+	/* Everything looks good, so set do_gettimeoffset*/
+	do_gettimeoffset = do_gettimeoffset_cyclone;	
+}
+
+#else /*CONFIG_X86_CYCLONE*/
+
+#define use_cyclone 0
+static void mark_timeoffset_cyclone(void) {}
+static unsigned long do_gettimeoffset_cyclone(void) {return 0;}
+static void init_cyclone_clock(void) {}
+
+#endif /*CONFIG_X86_CYCLONE*/
+
 #ifndef CONFIG_X86_TSC
 
 /* This function must be called with interrupts disabled 
@@ -508,7 +640,8 @@ static void timer_interrupt(int irq, voi
 
 		count = ((LATCH-1) - count) * TICK_SIZE;
 		delay_at_last_interrupt = (count + LATCH/2) / LATCH;
-	}
+	} else if (use_cyclone)
+		mark_timeoffset_cyclone();
  
 	do_timer_interrupt(irq, NULL, regs);
 
@@ -699,6 +832,9 @@ void __init time_init(void)
 		}
 	}
 
+	if((!use_tsc) && use_cyclone)
+		init_cyclone_clock();
+
 #ifdef CONFIG_VISWS
 	printk("Starting Cobalt Timer system clock\n");
 
diff -urNp x-ref/include/asm-i386/fixmap.h x/include/asm-i386/fixmap.h
--- x-ref/include/asm-i386/fixmap.h	Mon Sep 30 03:47:21 2002
+++ x/include/asm-i386/fixmap.h	Mon Sep 30 03:47:32 2002
@@ -64,6 +64,9 @@ enum fixed_addresses {
 #ifndef CONFIG_X86_F00F_WORKS_OK
 	FIX_F00F,
 #endif
+#ifdef CONFIG_X86_CYCLONE
+	FIX_CYCLONE_TIMER, /*cyclone timer register*/
+#endif 
 #ifdef CONFIG_HIGHMEM
 	FIX_KMAP_BEGIN,	/* reserved pte's for temporary kernel mappings */
 	FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1,