Hi all,<br><br><font size="1">Target : PowerPC, Virtex-440 Generic </font><br><font size="1">Serial port : Xilinx 16550 Uart ( depends on OF_PLATFORM</font>)<br><br>Further investigation of KGDBOC on PowerPC shows that kgdboc hangs at :<br>
<br>In file : <span style="background-color: rgb(204, 204, 204);">arch/powerpc/include/asm/kgdb.h</span><br><br><b><span style="color: rgb(0, 153, 0);">static inline void</span></b> arch_kgdb_breakpoint(<b><span style="color: rgb(0, 102, 0);">void</span></b>)<br>
{<br> <b style="color: rgb(255, 153, 0);">asm</b>(<b><span style="color: rgb(153, 51, 153);">".long 0x7d821008"</span></b>); /* <b><span style="color: rgb(51, 153, 153);">twge r2, r2 </span></b>*/ <b style="color: rgb(255, 0, 0);"> << ---- KGDBOC Hangs here</b> <b style="color: rgb(255, 0, 0);"> << ---</b><br>
<br><br>-----------------------------------------<br><span style="background-color: rgb(204, 204, 204);">Debug Log:</span><br style="background-color: rgb(204, 204, 204);"><br><span style="color: rgb(51, 51, 51);">root@10.1.2.55:~# echo g > /proc/sysrq-trigger </span><br style="color: rgb(51, 51, 51);">
<span style="color: rgb(51, 51, 51);">SysRq : GDB </span><br style="color: rgb(51, 51, 51);"><span style="color: rgb(51, 51, 51);">1------------------------>sysrq_handle_gdb </span><br style="color: rgb(51, 51, 51);">
<span style="color: rgb(51, 51, 51);">Entering KGDB </span><br style="color: rgb(51, 51, 51);"><span style="color: rgb(51, 51, 51);">1-1----------------------->kgdb_breakpoint </span><br style="color: rgb(51, 51, 51);">
<span style="color: rgb(51, 51, 51);">1-2----------------------->kgdb_breakpoint </span><br style="color: rgb(51, 51, 51);"><span style="color: rgb(51, 51, 51);">1-3----------------------->kgdb_breakpoint </span><br style="color: rgb(51, 51, 51);">
<span style="color: rgb(51, 51, 51);">1-1----------------------->arch_kgdb_breakpoint </span><br><br>---------------------------------------------<br><br><br>Any comments or suggestions ????<br><br>-Srikanth<br>----------<br>
<br><div class="gmail_quote">On Mon, May 4, 2009 at 8:12 PM, Bruce Ashfield <span dir="ltr"><<a href="mailto:bruce.ashfield@gmail.com">bruce.ashfield@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<div class="im">On Mon, May 4, 2009 at 9:13 AM, srikanth krishnakar<br>
<<a href="mailto:skrishnakar@gmail.com">skrishnakar@gmail.com</a>> wrote:<br>
><br>
><br>
> Hi all,<br>
><br>
> I need help in kgdboc testing on PowerPC target.<br>
<br>
</div>Have you tried contacting the maintainer ? (I noticed that Jason<br>
wasn't cc'd), just in case it isn't simply a use case problem and<br>
might be related to KGDB internals.<br>
<br>
KGDB<br>
P: Jason Wessel<br>
M: <a href="mailto:jason.wessel@windriver.com">jason.wessel@windriver.com</a><br>
<br>
I've tested KGDBOC up to the 2.6.29 kernel and it worked fine<br>
on a series of 85xx boards. I haven't had a chance on 2.6.30-rcX<br>
yet, so something may have changed.<br>
<div><div></div><div class="h5"><br>
><br>
> Linux Kernel: 2.6.30-rc4<br>
> KGDB method : KGDBOC<br>
> Arch: PowerPC<br>
><br>
> Note: Attached is the kernel config used.<br>
><br>
> Has anyone tested KGDBOC for Serial 8250, and the serial port has dependency<br>
> on OF_PLATFORM driver ?<br>
><br>
> Here are the kernel config options:<br>
><br>
> Device Drivers ---><br>
> Character devices ---><br>
> Serial drivers ---><br>
> <*> 8250/16550 and<br>
> compatible serial support<br>
> [*] Console on<br>
> 8250/16550 and compatible serial port<br>
> (4) Number of<br>
> 8250/16550 serial ports to register at runtime<br>
> [ ] Extended 8250/16550<br>
> serial driver options<br>
> *** Non-8250 serial<br>
> port support ***<br>
> <*> Xilinx uartlite<br>
> serial port support<br>
> [*] Support for<br>
> console on Xilinx uartlite serial port<br>
> < > Digi International<br>
> NEO PCI Support<br>
> <*> Serial port on Open<br>
> Firmware platform bus<br>
> < > NWP serial port<br>
> driver<br>
><br>
> Kernel hacking ---><br>
> -*- Magic SysRq key<br>
> [*] Kernel debugging<br>
> [*] KGDB: kernel debugging with remote gdb ---><br>
> --- KGDB: kernel debugging with remote<br>
> gdb<br>
> <*> KGDB: use kgdb over the serial console<br>
><br>
><br>
> ----------------------------------------------<br>
> In the process :<br>
><br>
> On the target side :<br>
><br>
> ...............<br>
> Serial: 8250/16550 driver, 4 ports, IRQ sharing<br>
> disabled<br>
> 83e00000.serial: ttyS0 at MMIO 0x83e01003 (irq<br>
> = 16) is a<br>
> 16550A<br>
> console [ttyS0]<br>
> enabled<br>
> kgdb: Registered I/O driver kgdboc.<br>
> .................<br>
><br>
> root@10.161.2.35:~# echo g > /proc/sysrq-trigger<br>
> SysRq : GDB<br>
> Entering KGDB<br>
><br>
><br>
> On host side :<br>
><br>
> [root@srikant linux-2.6]# powerpc-linux-gnu-gdb<br>
> vmlinux-puru<br>
> GNU gdb G++ 4.3-150) 6.8.50.20081022-cvs<br>
> Copyright (C) 2008 Free Software Foundation, Inc.<br>
> License GPLv3+: GNU GPL version 3 or later<br>
> <<a href="http://gnu.org/licenses/gpl.html" target="_blank">http://gnu.org/licenses/gpl.html</a>><br>
> This is free software: you are free to change and<br>
> redistribute it.<br>
> There is NO WARRANTY, to the extent permitted by<br>
> law. Type "show copying"<br>
> and "show warranty" for details.<br>
> This GDB was configured as<br>
> "--host=i686-pc-linux-gnu --target=powerpc-linux-gnu".<br>
> For bug reporting instructions, please see:<br>
> (gdb) set remotebaud 9600<br>
> (gdb) target remote /dev/ttyS0<br>
> Remote debugging using /dev/ttyS0<br>
> Ignoring packet error, continuing...<br>
> warning: unrecognized item "timeout" in<br>
> "qSupported" response<br>
> Ignoring packet error, continuing...<br>
> Ignoring packet error, continuing...<br>
> Ignoring packet error, continuing...<br>
> Ignoring packet error, continuing...<br>
> Ignoring packet error, continuing...<br>
> Malformed response to offset query, timeout<br>
<br>
</div></div>I'm wondering if there is a GDB protocol mismatch and your<br>
version of GDB is sending packets that KGDB can't handle.<br>
I'm no where near an expert on GDB's protocol and won't know<br>
if I'm seeing the same thing until I try 2.6.30-rc<br>
<br>
Bruce<br>
<div class="im"><br>
><br>
> Can anybody comment on the steps followed in the process of testing or<br>
> something is missing with respect to of_serial.c for powerpc architecture.<br>
> Seems the target has never responded for gdb requests !!!<br>
><br>
><br>
> Regards<br>
> Srikanth<br>
><br>
><br>
><br>
><br>
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><br>
<font color="#888888"><br>
<br>
<br>
--<br>
"Thou shalt not follow the NULL pointer, for chaos and madness await<br>
thee at its end"<br>
</font></blockquote></div><br><br clear="all"><br>-- <br>"The Good You Do, The Best You GET"<br><br>Regards<br>Srikanth Krishnakar<br>**********************<br>