On Mon, Oct 11, 2010 at 8:06 PM, Øyvind Harboe <oyvind.har...@zylin.com> wrote: > On Mon, Oct 11, 2010 at 12:36 AM, Michael Hope <michael.h...@linaro.org> > wrote: >> Hi Øyvind. You might want to ask the OpenOCD list about this. I've >> used the DCC as an end user before for sending printf() style messages >> and RPC over and it's quite good for that. > > I did, no response. (I'm also one of the main OpenOCD maintainers :-)
Heh. I spotted the @zylin address but didn't twig past that. >> I'm not sure how your proposal would work though. My understanding is >> that the DCC is only accessible over JTAG and, if you already have a >> JTAG connection, then you might as well use that to debug. > > OpenOCD / JTAG is not great for application debugging. > > What I envisage is to use gdbserver for application debugging and > JTAG for kernel debugging. gdbserver would talk over JTAG DCC > serial port and kernel debugging would happen via normal JTAG > debugging. > > In "normal" JTAG debugging mode the CPU is halted. > > Here are some commercial implementations of kernel + application > debugging: > > www.arium.com/pdf/CompleteLinuxDebugging.pdf Ah, I see. You use the JTAG unit and on-chip debug hardware for the kernel and use the JTAG-supplied DCC connection for applications. So you can use the DCC instead of Ethernet or serial, which is nice as it frees up a port. You might want to ask linaro-...@lists about this and see if any of the kernel guys know about kernel support. A quick poke about shows that you can send the kernel's printf() style debug messages through it but little else. -- Michael _______________________________________________ linaro-toolchain mailing list linaro-toolchain@lists.linaro.org http://lists.linaro.org/mailman/listinfo/linaro-toolchain
