Start of an attempt to unify support for GT64120 based boards.

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+README for arch/mips/gt64120 directory and subdirectories
+
+Jun Sun, jsun@mvista.com or jsun@junsun.net
+01/27, 2001
+
+MOTIVATION
+----------
+
+Many MIPS boards share the same system controller (or CPU companian chip),
+such as GT-64120.  It is highly desirable to let these boards share
+the same controller code instead of duplicating them.
+
+This directory is meant to hold all MIPS boards that use GT-64120 or GT-64120A.
+
+
+HOW TO ADD A BOARD
+------------------
+ 
+. Create a subdirectory include/asm/gt64120/<board>.  
+
+. Create a file called gt64120_dep.h under that directory.
+
+. Modify include/asm/gt64120/gt64120.h file to include the new gt64120_dep.h
+  based on config options.  The board-dep section is at the end of 
+  include/asm/gt64120/gt64120.h file. There you can find all required
+  definitions include/asm/gt64120/<board>/gt64120_dep.h file must supply.
+
+. Create a subdirectory arch/mips/gt64120/<board> directory to hold
+  board specific routines.
+
+. The GT-64120 common code is supplied under arch/mips/gt64120/common directory.
+  It includes:
+	1) arch/mips/gt64120/pci.c -
+		common PCI routine, include the top-level pcibios_init()
+	2) arch/mips/gt64120/irq.c -
+		common IRQ routine, include the top-level do_IRQ() 
+	   [This part really belongs to arch/mips/kernel. jsun]
+ 	3) arch/mips/gt64120/gt_irq.c -
+		common IRQ routines for GT-64120 chip.  Currently it only handles
+	 	the timer interrupt.
+
+. Board-specific routines are supplied under arch/mips/gt64120/<board> dir.
+	1) arch/mips/gt64120/<board>/pci.c - it provides bus fixup routine
+	2) arch/mips/gt64120/<board>/irq.c - it provides enable/disable irqs
+		and board irq setup routine (irq_setup)
+	3) arch/mips/gt64120/<board>/int-handler.S -
+		The first-level interrupt dispatching routine.
+	4) a bunch of other "normal" stuff (setup, prom, dbg_io, reset, etc)
+
+. Follow other "normal" procedure to modify configuration files, etc.
+
+
+TO-DO LIST
+----------
+
+. Expand arch/mips/gt64120/gt_irq.c to handle all GT-64120 interrupts.
+  We probably need to introduce GT_IRQ_BASE  in board-dep header file,
+  which is used the starting irq_nr for all GT irqs.
+
+  A function, gt64120_handle_irq(), will be added so that the first-level
+  irq dispatcher will call this function if it detects an interrupt
+  from GT-64120.
+
+. More support for GT-64120 PCI features (2nd PCI bus, perhaps)
+