New manual. First version to CVS. Just starting to see if it builds.

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+@chapter CPU Initialization
+
+This section describes the general CPU and system initialization sequence
+as it pertains to the CPU dependent code.
+
+@section Introduction
+
+XXX general startup sequence description rewritten to make it more
+applicable to CPU depdent code in executive
+
+@section CPU Dependent Configuration Table
+
+The CPU Dependent Configuration Table contains information which tailors
+the behavior of RTEMS base Some of the fields in this table are required
+to be present in all ports of RTEMS.  These fields appear at the beginning
+of the data structure.  Fields past this point may be CPU family and CPU
+model dependent.  For example, a port may add a field to specify the
+default value for an interrupt mask register on the CPU.  This table is
+initialized by the Board Support Package and passed to the
+rtems_initialize_executive or rtems_initialize_executive_early directive.
+
+@example
+typedef struct @{
+  void       (*pretasking_hook)( void );
+  void       (*predriver_hook)( void );
+  void       (*postdriver_hook)( void );
+  void       (*idle_task)( void );
+  boolean      do_zero_of_workspace;
+  unsigned32   idle_task_stack_size;
+  unsigned32   interrupt_stack_size;
+  unsigned32   extra_mpci_receive_server_stack;
+  void *     (*stack_allocate_hook)( unsigned32 );
+  void       (*stack_free_hook)( void* );
+  /* end of fields required on all CPUs */
+
+  unsigned32   some_other_cpu_dependent_info;
+@}   rtems_cpu_table;
+@end example
+
+XXX copy the descriptions of the fields from another CPU supplement
+
+@section Initializing the CPU
+
+The _CPU_Initialize routine performs processor dependent initialization.
+
+@example
+void _CPU_Initialize(
+  rtems_cpu_table  *cpu_table,
+  void            (*thread_dispatch)  /* may be ignored */
+)
+@end example
+
+The thread_dispatch argument is the address of the entry point for the
+routine called at the end of an ISR once it has been decided a context
+switch is necessary.  On some compilation systems it is difficult to call
+a high-level language routine from assembly.  Providing the address of the
+_Thread_ISR_Dispatch routine allows the porter an easy way to obtain this
+critical address and thus provides an easy way to work around this
+limitation on these systems.
+
+If you encounter this problem save the entry point in a CPU dependent
+variable as shown below:
+
+@example
+_CPU_Thread_dispatch_pointer = thread_dispatch;
+@end example
+
+
+During the initialization of the context for tasks with floating point,
+the CPU dependent code is responsible for initializing the floating point
+context.  If there is not an easy way to initialize the FP context during
+Context_Initialize, then it is usually easier to save an "uninitialized"
+FP context here and copy it to the task's during Context_Initialize.  If
+this technique is used to initialize the FP contexts, then it is important
+to ensure that the state of the floating point unit is in a coherent,
+initialized state.
+
+Finally, this routine is responsible for copying the application's CPU
+Table into a locally accessible and modifiable area.  This is shown below:
+
+@example
+_CPU_Table = *cpu_table;
+@end example
+
+