[x86 arch split]

Add better documentation to the hooks.

arch/i386/generic/do_timer.h

 /* defines for inline arch setup functions */
 
+/**
+ * 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.
+ **/
+
 static inline void do_timer_interrupt_hook(struct pt_regs *regs)
 {
 	do_timer(regs);
@@ -22,6 +33,15 @@ static inline void do_timer_interrupt_hook(struct pt_regs *regs)
 
 #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;

arch/i386/generic/entry_arch.h

+/*
+ * This file is designed to contain the BUILD_INTERRUPT specifications for
+ * all of the extra named interrupt vectors used by the architecture.
+ * Usually this is the Inter Process Interrupts (IPIs)
+ */
+
 /*
  * The following vectors are part of the Linux architecture, there
  * is no hardware IRQ pin equivalent for them, they are triggered

arch/i386/generic/irq_vectors.h

+/*
+ * This file should contain #defines for all of the interrupt vector
+ * numbers used by this architecture.
+ *
+ * In addition, there are some standard defines:
+ *
+ *	FIRST_EXTERNAL_VECTOR:
+ *		The first free place for external interrupts
+ *
+ *	SYSCALL_VECTOR:
+ *		The IRQ vector a syscall makes the user to kernel transition
+ *		under.
+ *
+ *	TIMER_IRQ:
+ *		The IRQ number the timer interrupt comes in at.
+ *
+ *	NR_IRQS:
+ *		The total number of interrupt vectors (including all the
+ *		architecture specific interrupts) needed.
+ *
+ */			
 #ifndef _ASM_IRQ_VECTORS_H
 #define _ASM_IRQ_VECTORS_H
 

arch/i386/generic/setup.c

@@ -9,6 +9,15 @@
 #include <linux/interrupt.h>
 #include <asm/arch_hooks.h>
 
+/**
+ * pre_intr_init_hook - initialisation prior to setting up interrupt vectors
+ *
+ * Description:
+ *	Perform any necessary interrupt initialisation prior to setting up
+ *	the "ordinary" interrupt call gates.  For legacy reasons, the ISA
+ *	interrupts should be initialised here if the machine emulates a PC
+ *	in any way.
+ **/
 void __init pre_intr_init_hook(void)
 {
 	init_ISA_irqs();
@@ -19,6 +28,15 @@ void __init pre_intr_init_hook(void)
  */
 static struct irqaction irq2 = { no_action, 0, 0, "cascade", NULL, NULL};
 
+/**
+ * intr_init_hook - post gate setup interrupt initialisation
+ *
+ * Description:
+ *	Fill in any interrupts that may have been left out by the general
+ *	init_IRQ() routine.  interrupts having to do with the machine rather
+ *	than the devices on the I/O bus (like APIC interrupts in intel MP
+ *	systems) are started here.
+ **/
 void __init intr_init_hook(void)
 {
 #ifdef CONFIG_X86_LOCAL_APIC
@@ -28,22 +46,52 @@ void __init intr_init_hook(void)
 	setup_irq(2, &irq2);
 }
 
+/**
+ * pre_setup_arch_hook - hook called prior to any setup_arch() execution
+ *
+ * Description:
+ *	generally used to activate any machine specific identification
+ *	routines that may be needed before setup_arch() runs.  On VISWS
+ *	this is used to get the board revision and type.
+ **/
 void __init pre_setup_arch_hook(void)
 {
 }
 
+/**
+ * trap_init_hook - initialise system specific traps
+ *
+ * Description:
+ *	Called as the final act of trap_init().  Used in VISWS to initialise
+ *	the various board specific APIC traps.
+ **/
 void __init trap_init_hook(void)
 {
 }
 
 static struct irqaction irq0  = { timer_interrupt, SA_INTERRUPT, 0, "timer", NULL, NULL};
 
+/**
+ * time_init_hook - do any specific initialisations for the system timer.
+ *
+ * Description:
+ *	Must plug the system timer interrupt source at HZ into the IRQ listed
+ *	in irq_vectors.h:TIMER_IRQ
+ **/
 void __init time_init_hook(void)
 {
 	setup_irq(0, &irq0);
 }
 
 #ifdef CONFIG_MCA
+/**
+ * mca_nmi_hook - hook into MCA specific NMI chain
+ *
+ * Description:
+ *	The MCA (Microchannel Arcitecture) has an NMI chain for NMI sources
+ *	along the MCA bus.  Use this to hook into that chain if you will need
+ *	it.
+ **/
 void __init mca_nmi_hook(void)
 {
 	/* If I recall correctly, there's a whole bunch of other things that

arch/i386/generic/setup_arch_post.h

-/* Hook for machine specific memory setup.
+/**
+ * machine_specific_memory_setup - Hook for machine specific memory setup.
  *
- * This is included late in kernel/setup.c so that it can make use of all of
- * the static functions. */
+ * Description:
+ *	This is included late in kernel/setup.c so that it can make
+ *	use of all of the static functions.
+ **/
 
 static inline char * __init machine_specific_memory_setup(void)
 {