Q-ha, You didn't give enough details about what you tried for us guess what is wrong, but there are several issues with debugging U-Boot or ppcboot with the bdi2000 which require a good understanding of what is going on. Here is some info that may be of help. I also have a request for you or anyone else using the 745x processors with the BDI2000 at the end of this message.
In addition to the issue Mark pointed out, you can't use soft breakpoints while you are running from ROM which is the common case for the early init parts of U-Boot. Also, once U-Boot has relocated itself, you need to identify the new base address and inform gdb of the new load address. In this example GDB session, I have my BDI config file set up for address translation and software breakpoints. I have included some command options which are the defaults to make it more clear what is going on. I have also added some comments inline: [brad at gizmo u-boot]$ ppc-linux-gdb 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". (gdb) add-symbol-file u-boot 0xfff00000 add symbol table from file "u-boot" at .text_addr = 0xfff00000 (y or n) y Reading symbols from u-boot...done. //// We didn't need the address above, but I wanted to make it clear //// how it differs from the later use of add-symbol-file. (gdb) target remote 10.100.50.221:2001 Remote debugging using 10.100.50.221:2001 _start () at /d/build/brad/u-boot-discov/u-boot/cpu/74xx_7xx/start.S:94 94 li r21, BOOTFLAG_COLD /* Normal Power-On: Boot from FLASH */ (gdb) b boot_cold Breakpoint 1 at 0xfff02000: file /d/build/brad/u-boot-discov/u-boot/cpu/74xx_7xx/start.S, line 271. (gdb) d Delete all breakpoints? (y or n) y //// We can't use software breakpoints yet so the above was just an easy //// way to get the address where we want to set our hardware breakpoint. (gdb) mon bi 0xfff02000 p Breakpoint identification is 0 //// The monitor command is a handy way to avoid switching to a telnet //// window to use the telnet interface. The p option forces a physical //// mode breakpoint. (gdb) cont Continuing. Program received signal SIGTRAP, Trace/breakpoint trap. boot_warm () at /d/build/brad/u-boot-discov/u-boot/cpu/74xx_7xx/start.S:271 271 li r0, 0 (gdb) list in_flash 319 /* perform low-level init */ 320 /* sdram init, galileo init, etc */ 321 /* r3: NHR bit from HID0 */ 322 323 /* setup the bats */ 324 bl setup_bats 325 sync 326 327 /* 328 * Cache must be enabled here for stack-in-cache trick. (gdb) 329 * This means we need to enable the BATS. 330 * This means: 331 * 1) for the EVB, original gt regs need to be mapped 332 * 2) need to have an IBAT for the 0xf region, 333 * we are running there! 334 * Cache should be turned on after BATs, since by default 335 * everything is write-through. 336 * The init-mem BAT can be reused after reloc. The old 337 * gt-regs BAT can be reused after board_init_f calls 338 * board_pre_init (EVB only). (gdb) 339 */ 340 #if !defined(CONFIG_BAB7xx) && !defined(CONFIG_ELPPC) 341 /* enable address translation */ 342 bl enable_addr_trans 343 sync 344 345 #if 1 346 /* enable and invalidate the data cache */ 347 bl l1dcache_enable 348 #endif (gdb) b 343 Breakpoint 3 at 0xfff0203c: file /d/build/brad/u-boot-discov/u-boot/cpu/74xx_7xx/start.S, line 343. (gdb) d Delete all breakpoints? (y or n) y (gdb) mon ci (gdb) mon bi 0xfff0203c v Breakpoint identification is 0 //// We just turned on address translation so the rest of our hardware //// breakpoints must use virtual mode, thus the v above. (gdb) cont Continuing. Program received signal SIGTRAP, Trace/breakpoint trap. in_flash () at /d/build/brad/u-boot-discov/u-boot/cpu/74xx_7xx/start.S:343 343 sync (gdb) symbol-file Discard symbol table from `/d/build/brad/u-boot-discov/u-boot/u-boot'? (y or n) y No symbol file now. (gdb) add-symbol-file u-boot 0x0ffb8000 add symbol table from file "u-boot" at .text_addr = 0xffb8000 (y or n) y Reading symbols from u-boot...done. //// Prepare to set breakpoints after we relocate to RAM. Throw out //// the old symbol table and reload it with the correct base address //// (which we got from examining the code or as reported by U-Boot before //// it began running in RAM. (gdb) b after_reloc Breakpoint 5 at 0xffba92c: file db64360.c, line 416. (gdb) d Delete all breakpoints? (y or n) y (gdb) mon ci (gdb) mon bi 0xffba92c v Breakpoint identification is 0 (gdb) cont Continuing. Program received signal SIGTRAP, Trace/breakpoint trap. after_reloc (gd=0xff96f9c, dest_addr=268140544) at db64360.c:416 416 board_init_r(gd, dest_addr); //// OK. Now we are in RAM and we can use soft breakpoints from here //// on out. (gdb) b board_init_r Breakpoint 6 at 0xffc14a0: file board.c, line 589. (gdb) cont Continuing. Program received signal SIGTRAP, Trace/breakpoint trap. after_reloc (gd=0xff96f9c, dest_addr=268140544) at db64360.c:416 416 board_init_r(gd, dest_addr); (gdb) list 411 } 412 memoryMapDeviceSpace(BOOT_DEVICE, CFG_FLASH_BASE, CFG_FLASH_SIZE); 413 #endif 414 415 /* now, jump to the main ppcboot board init code */ 416 board_init_r(gd, dest_addr); 417 418 /* NOTREACHED */ 419 } 420 (gdb) print /x dest_addr $1 = 0xffb8000 (gdb) step Once you get all this working, could you please do me a favor and let me know if you ever have any problems with single step ("mon ti" or "stepi") not working? I have a lot of trouble with this with my 7447/Discovery II combo and I am trying to figure out if it is a board issue or a processor issue or a BDI issue. --Brad Q-ha Park writes: > > [I apologize this question is off topic in this mailing > list:ppc-embedded. But I coundn't find a better place to ask, > ppcboot-users is inactive..] > > I'm new to BDI2000, and after reading a manual that came with the tool, > I tried to debug ppcboot using bdi2000 and gdb. The problem is I just > can't set the breakpoint whether be it software or hardware breakpoint; > For example, when I set the break point at "boot_cold" and type > "continue", the program just runs without ever stopping at the > breakpoint where it's supposed to stop! > > Here's what I did: > a. turn on bdi2000. > b. connect to bdi2000 in gdb session. > c. set the breakpoint > d. type "continue" > > ========== > 90 li r21, BOOTFLAG_COLD /* Normal Power-On: Boot > from FLASH */ > (gdb) l > 85 .ascii CONFIG_IDENT_STRING, "\0" > 86 > 87 . = EXC_OFF_SYS_RESET > 88 .globl _start > 89 _start: > 90 li r21, BOOTFLAG_COLD /* Normal Power-On: Boot > from FLASH */ > 91 b boot_cold > 92 sync > 93 > 94 . = EXC_OFF_SYS_RESET + 0x10 > (gdb) b boot_cold > Breakpoint 1 at 0xfff02000: file > /home/users/qpark/hobby/ppcboot-1.1.6/cpu/74xx_7xx/start.S, line 253. > (gdb) cont > Continuing. > (continues for good...) > ========== > > What am I probably doing wrong? FYI, I tried to remove H/W breakpoint > before I entered "go" > > Any help would be greatly appreciated!! > > ::::::::::::::::::::::::::::::::::::::::::::::::: > Q-ha Park > > ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/