[U-Boot-Users] How to write a kgdb.S for AT91RM9200?

[peike]

Hello,Wolfgang Denk

    At first,Thank you for you give me some advice.Now,I'm using the u-boot-
1.1.4 as bootloader for AT91RM9200DK and arm linux 2.6.14-rc2.However,the old  
question is:If I want to add a debugging stub(at91rm9200dk-stub.c or
gdbserver)into u-boot-1.1.4,you say "It does work, but requires you to add the 
missing cpu/*/kgdb.S file, and this is not a difficult task, just a somewhat 
laborious task."can you give me some details about it?
    how to write the missing /u-boot-1.1.4/ cpu/at91rm9200/kgdb.S file,i find 
a kgdb.S file in /u-boot-1.1.4/cpu/ppc4xx , i want to modify it for /u-boot-
1.1.4/cpu/arm920t/at91rm9200. how to do it? The following is /u-boot-
1.1.4/cpu/ppc4xx/kgdb.S source file.
/*
 *  Copyright (C) 2000	Murray Jensen <Murray.Jensen at cmst.csiro.au>
 *
 * See file CREDITS for list of people who contributed to this
 * project.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 * MA 02111-1307 USA
 */

#include <config.h>
#include <command.h>
#include <ppc4xx.h>
#include <version.h>

#define CONFIG_405GP 1		/* needed for Linux kernel header files */
#define _LINUX_CONFIG_H 1	/* avoid reading Linux autoconf.h file	*/

#include <ppc_asm.tmpl>
#include <ppc_defs.h>

#include <asm/cache.h>
#include <asm/mmu.h>

#if (CONFIG_COMMANDS & CFG_CMD_KGDB)
 /*
 * cache flushing routines for kgdb
 */

	.globl	kgdb_flush_cache_all
kgdb_flush_cache_all:
	/* icache */
	iccci   r0,r0		/* iccci invalidates the entire I cache */
	/* dcache */
	addi    r6,0,0x0000     /* clear GPR 6 */
	addi    r7,r0, 128 	/* do loop for # of dcache lines */
				/* NOTE: dccci invalidates both */
	mtctr   r7              /* ways in the D cache */
..dcloop:
	dccci   0,r6            /* invalidate line */
	addi    r6,r6, 32	/* bump to next line */
	bdnz    ..dcloop
	blr

	.globl	kgdb_flush_cache_range
kgdb_flush_cache_range:
	li	r5,CFG_CACHELINE_SIZE-1
	andc	r3,r3,r5
	subf	r4,r3,r4
	add	r4,r4,r5
	srwi.	r4,r4,CFG_CACHELINE_SHIFT
	beqlr
	mtctr	r4
	mr	r6,r3
1:	dcbst	0,r3
	addi	r3,r3,CFG_CACHELINE_SIZE
	bdnz	1b
	sync			/* wait for dcbst's to get to ram */
	mtctr	r4
2:	icbi	0,r6
	addi	r6,r6,CFG_CACHELINE_SIZE
	bdnz	2b
	SYNC
	blr

#endif /* CFG_CMD_KGDB */

Please help me!
Thank you very much!

Best regards,
peike