[U-Boot-Users] Debugging u-boot goes to 0x70c (Program exception)

[Shawn]

Hi,

I have problem in flash_init() to get correct manufacturer's ID. So I
want to debug the function.

Once I set a breakpoint at flash_init() and issue a continue command, gdb
always shows that the program stops at 0x0000070c, which means a program
exception. A program exception can be caused by an illegal instruction, a
privileged instruction, or a trap. I don't know which caused this
exception in my case. I'm wondering it may not be u-boot itself but the
way I'm debugging that caused this exception. So I attached the whole
procedure I did, not very much long. Would anybody give me some hints?
Thanks a lot.

-Shawn.

% ppc_82xx-gdb u-boot
GNU gdb 5.1.1
Copyright 2002 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you
are
welcome to change it and/or distribute copies of it under certain
conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for
details.
This GDB was configured as "--host=i386-redhat-linux
--target=ppc-linux"...
0xfff00100 in ?? ()

(gdb) mon bi 0xffe00100
Breakpoint identification is 0
(gdb) mon go
(gdb) mon ci
(gdb) symbol-file
Discard symbol table from `/u/code/u-boot-1.1.1/u-boot'? (y or n) y
No symbol file now.
(gdb) add-symbol-file u-boot 0x7fd9000
add symbol table from file "u-boot" at
        .text_addr = 0x7fd9000
(y or n) y
Reading symbols from u-boot...done.
(gdb) b board_init_r
Breakpoint 1 at 0x7fdc9b4: file board.c, line 566.
(gdb) d
Delete all breakpoints? (y or n) y
(gdb) mon bi 0x7fdc9b4
Breakpoint identification is 0
(gdb) c
Continuing.

Program received signal SIGTRAP, Trace/breakpoint trap.
board_init_r (id=0x7fa8f98, dest_addr=0x7fd9000) at board.c:566
566             gd = id;                /* initialize RAM version of
global data
 */
(gdb) mon break soft
(gdb) b flash_init
Breakpoint 2 at 0x7fe1254: file flash.c, line 126.
(gdb) c
Continuing.

Program received signal SIGSTOP, Stopped (signal).
0x0000070c in ?? ()
(gdb)


U-Boot 1.1.1 (Jun 22 2004 - 15:49:59)

CPU:   MPC8245 Revision 1.2 at 249.999 MHz: 16 kB I-Cache 16 kB D-Cache
Board: MP8245, local bus @ 99.999 MHz
DRAM:  128 MB
Top of RAM usable for U-Boot at: 08000000
Reserving 152k for U-Boot at: 07fd9000
Reserving 192k for malloc() at: 07fa9000
Reserving 56 Bytes for Board Info at: 07fa8fc8
Reserving 48 Bytes for Global Data at: 07fa8f98
Stack Pointer at: 07fa8f78
New Stack Pointer is: 07fa8f78
Now running in RAM - U-Boot at: 07fd9000
FLASH: 



	
		
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