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	Correct spelling of "U-Boot" shall be used in all written text (documentation, comments in source files etc.). Signed-off-by: Bin Meng <bmeng.cn@gmail.com> Reviewed-by: Heiko Schocher <hs@denx.de> Reviewed-by: Simon Glass <sjg@chromium.org> Reviewed-by: Minkyu Kang <mk7.kang@samsung.com>
		
			
				
	
	
		
			196 lines
		
	
	
		
			6.5 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			196 lines
		
	
	
		
			6.5 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
| By Vlad Lungu vlad.lungu@windriver.com 2007-Oct-01
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| ----------------------------------------
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| Qemu is a full system emulator. See
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| 
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| http://www.nongnu.org/qemu/
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| 
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| Limitations & comments
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| ----------------------
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| Supports the "-M mips" configuration of qemu: serial,NE2000,IDE.
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| Supports little and big endian as well as 32 bit and 64 bit.
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| Derived from au1x00 with a lot of things cut out.
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| 
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| Supports emulated flash (patch Jean-Christophe PLAGNIOL-VILLARD) with
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| recent qemu versions. When using emulated flash, launch with
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| -pflash <filename> and erase mips_bios.bin.
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| 
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| 
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| Notes for the Qemu MIPS port
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| ----------------------------
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| 
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| I) Example usage:
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| 
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| Using u-boot.bin as ROM (replaces Qemu monitor):
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| 
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| 32 bit, big endian:
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| # make qemu_mips
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| # qemu-system-mips -M mips -bios u-boot.bin -nographic
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| 
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| 32 bit, little endian:
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| # make qemu_mipsel
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| # qemu-system-mipsel -M mips -bios u-boot.bin -nographic
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| 
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| 64 bit, big endian:
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| # make qemu_mips64
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| # qemu-system-mips64 -cpu MIPS64R2-generic -M mips -bios u-boot.bin -nographic
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| 
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| 64 bit, little endian:
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| # make qemu_mips64el
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| # qemu-system-mips64el -cpu MIPS64R2-generic -M mips -bios u-boot.bin -nographic
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| 
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| or using u-boot.bin from emulated flash:
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| 
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| if you use a qemu version after commit 4224
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| 
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| create image:
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| # dd of=flash bs=1k count=4k if=/dev/zero
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| # dd of=flash bs=1k conv=notrunc if=u-boot.bin
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| start it (see above):
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| # qemu-system-mips[64][el] [-cpu MIPS64R2-generic] -M mips -pflash flash -nographic
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| 
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| 2) Download kernel + initrd
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| 
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| On ftp://ftp.denx.de/pub/contrib/Jean-Christophe_Plagniol-Villard/qemu_mips/
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| you can downland
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| 
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| #config to build the kernel
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| qemu_mips_defconfig
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| #patch to fix mips interrupt init on 2.6.24.y kernel
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| qemu_mips_kernel.patch
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| initrd.gz
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| vmlinux
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| vmlinux.bin
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| System.map
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| 
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| 4) Generate uImage
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| 
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| # tools/mkimage -A mips -O linux -T kernel -C gzip -a 0x80010000 -e 0x80245650 -n "Linux 2.6.24.y" -d vmlinux.bin.gz uImage
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| 
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| 5) Copy uImage to Flash
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| # dd if=uImage bs=1k conv=notrunc seek=224 of=flash
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| 
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| 6) Generate Ide Disk
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| 
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| # dd of=ide bs=1k cout=100k if=/dev/zero
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| 
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| # sfdisk -C 261 -d ide
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| # partition table of ide
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| unit: sectors
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| 
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|      ide1 : start=       63, size=    32067, Id=83
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|      ide2 : start=    32130, size=    32130, Id=83
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|      ide3 : start=    64260, size=  4128705, Id=83
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|      ide4 : start=        0, size=        0, Id= 0
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| 
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| 7) Copy to ide
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| 
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| # dd if=uImage bs=512 conv=notrunc seek=63 of=ide
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| 
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| 8) Generate ext2 on part 2 on Copy uImage and initrd.gz
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| 
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| # Attached as loop device ide offset = 32130 * 512
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| # losetup -o 16450560 -f ide
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| # Format as ext2 ( arg2 : nb blocks)
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| # mke2fs /dev/loop0 16065
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| # losetup -d /dev/loop0
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| # Mount and copy uImage and initrd.gz to it
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| # mount -o loop,offset=16450560 -t ext2 ide /mnt
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| # mkdir /mnt/boot
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| # cp {initrd.gz,uImage} /mnt/boot/
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| # Umount it
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| # umount /mnt
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| 
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| 9) Set Environment
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| 
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| setenv rd_start 0x80800000
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| setenv rd_size 2663940
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| setenv kernel BFC38000
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| setenv oad_addr 80500000
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| setenv load_addr2 80F00000
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| setenv kernel_flash BFC38000
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| setenv load_addr_hello 80200000
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| setenv bootargs 'root=/dev/ram0 init=/bin/sh'
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| setenv load_rd_ext2 'ide res; ext2load ide 0:2 ${rd_start} /boot/initrd.gz'
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| setenv load_rd_tftp 'tftp ${rd_start} /initrd.gz'
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| setenv load_kernel_hda 'ide res; diskboot ${load_addr} 0:2'
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| setenv load_kernel_ext2 'ide res; ext2load ide 0:2 ${load_addr} /boot/uImage'
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| setenv load_kernel_tftp 'tftp ${load_addr} /qemu_mips/uImage'
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| setenv boot_ext2_ext2 'run load_rd_ext2; run load_kernel_ext2; run addmisc; bootm ${load_addr}'
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| setenv boot_ext2_flash 'run load_rd_ext2; run addmisc; bootm ${kernel_flash}'
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| setenv boot_ext2_hda 'run load_rd_ext2; run load_kernel_hda; run addmisc; bootm ${load_addr}'
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| setenv boot_ext2_tftp 'run load_rd_ext2; run load_kernel_tftp; run addmisc; bootm ${load_addr}'
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| setenv boot_tftp_hda 'run load_rd_tftp; run load_kernel_hda; run addmisc; bootm ${load_addr}'
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| setenv boot_tftp_ext2 'run load_rd_tftp; run load_kernel_ext2; run addmisc; bootm ${load_addr}'
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| setenv boot_tftp_flash 'run load_rd_tftp; run addmisc; bootm ${kernel_flash}'
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| setenv boot_tftp_tftp 'run load_rd_tftp; run load_kernel_tftp; run addmisc; bootm ${load_addr}'
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| setenv load_hello_tftp 'tftp ${load_addr_hello} /examples/hello_world.bin'
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| setenv go_tftp 'run load_hello_tftp; go ${load_addr_hello}'
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| setenv addmisc 'setenv bootargs ${bootargs} console=ttyS0,${baudrate} rd_start=${rd_start} rd_size=${rd_size} ethaddr=${ethaddr}'
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| setenv bootcmd 'run boot_tftp_flash'
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| 
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| 10) Now you can boot from flash, ide, ide+ext2 and tfp
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| 
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| # qemu-system-mips -M mips -pflash flash -monitor null -nographic -net nic -net user -tftp `pwd` -hda ide
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| 
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| II) How to debug U-Boot
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| 
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| In order to debug U-Boot you need to start qemu with gdb server support (-s)
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| and waiting the connection to start the CPU (-S)
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| 
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| # qemu-system-mips -S -s -M mips -pflash flash -monitor null -nographic -net nic -net user -tftp `pwd` -hda ide
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| 
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| in an other console you start gdb
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| 
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| 1) Debugging of U-Boot Before Relocation
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| 
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| Before relocation, the addresses in the ELF file can be used without any problems
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| by connecting to the gdb server localhost:1234
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| 
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| # mipsel-unknown-linux-gnu-gdb u-boot
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| GNU gdb 6.6
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| Copyright (C) 2006 Free Software Foundation, Inc.
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| GDB is free software, covered by the GNU General Public License, and you are
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| welcome to change it and/or distribute copies of it under certain conditions.
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| Type "show copying" to see the conditions.
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| There is absolutely no warranty for GDB.  Type "show warranty" for details.
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| This GDB was configured as "--host=i486-linux-gnu --target=mipsel-unknown-linux-gnu"...
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| (gdb)  target remote localhost:1234
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| Remote debugging using localhost:1234
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| _start () at start.S:64
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| 64		RVECENT(reset,0)	/* U-Boot entry point */
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| Current language:  auto; currently asm
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| (gdb)  b board.c:289
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| Breakpoint 1 at 0xbfc00cc8: file board.c, line 289.
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| (gdb) c
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| Continuing.
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| 
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| Breakpoint 1, board_init_f (bootflag=<value optimized out>) at board.c:290
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| 290		relocate_code (addr_sp, id, addr);
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| Current language:  auto; currently c
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| (gdb) p/x addr
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| $1 = 0x87fa0000
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| 
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| 2) Debugging of U-Boot After Relocation
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| 
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| For debugging U-Boot after relocation we need to know the address to which
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| U-Boot relocates itself to 0x87fa0000 by default.
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| And replace the symbol table to this offset.
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| 
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| (gdb) symbol-file
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| Discard symbol table from `/private/u-boot-arm/u-boot'? (y or n) y
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| Error in re-setting breakpoint 1:
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| No symbol table is loaded.  Use the "file" command.
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| No symbol file now.
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| (gdb) add-symbol-file u-boot 0x87fa0000
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| add symbol table from file "u-boot" at
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| 	.text_addr = 0x87fa0000
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| (y or n) y
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| Reading symbols from /private/u-boot-arm/u-boot...done.
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| Breakpoint 1 at 0x87fa0cc8: file board.c, line 289.
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| (gdb) c
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| Continuing.
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| 
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| Program received signal SIGINT, Interrupt.
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| 0xffffffff87fa0de4 in udelay (usec=<value optimized out>) at time.c:78
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| 78		while ((tmo - read_c0_count()) < 0x7fffffff)
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