Hello Grant, Is there any conclusion of the below discussion:
http://www.nabble.com/Question-about-DBCR0-initialization-for-440-td23049044.html Xilinx target (virtex5) hangs (while running GDBServer & KGDB) without the DBCR0 initialization. Can you please comment on this ? Thanks, -Srikanth On Wed, May 20, 2009 at 11:20 AM, srikanth krishnakar <skrishna...@gmail.com> wrote: > Hi David, > > I am not sure how the IDM behaves on few of PPC440 targets which don't > have boot loaders. I have a reference for your question: > > http://www.nabble.com/Question-about-DBCR0-initialization-for-440-td23049044.html > > Without this fix (given patch) I am facing problems with GDB, and > further target hangs while running gdbserver ! > > Thanks, > Srikanth > > On Wed, May 20, 2009 at 5:23 AM, David Gibson > <da...@gibson.dropbear.id.au> wrote: >> On Tue, May 19, 2009 at 06:38:53PM +0530, srikanth krishnakar wrote: >>> Hi, >>> >>> kernel- 2.6.29 >>> Debug technique: KGDB >>> >>> The PowerPC kernel does not initialize the PPC440 DBCR0 register. This >>> prevents the use of software breakpoints in case of internal debug >>> mode. Looking into head_fsl_booke.S for initialization of DBCR0 is >>> used by boot-loaders. >>> It seems head_44x.S lacks this step of DBCR0 register initialization. >>> So fixing this with initializing the DBCR0 register as shown below : >>> >>> Subject: [PATCH] powerpc: 44x: Initialize DBCR0 for targets not having >>> bootloader >>> >>> The kernel does not initialize the PPC440 DBCR0 register. >>> This prevents (among other things) the use of software >>> breakpoints with GDB. The boot loaders probably do initialize >>> this but few targets run without a boot loader >> >> Um.. how does this prevent the use of software breakpoints with gdb? >> The trap instructions still work with IDM==0. >> >> -- >> David Gibson | I'll have my music baroque, and my code >> david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ >> | _way_ _around_! >> http://www.ozlabs.org/~dgibson >> > > > > -- > "The Good You Do, The Best You GET" > > Regards > Srikanth Krishnakar > ********************** > -- "The Good You Do, The Best You GET" Regards Srikanth Krishnakar ********************** _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
