9fans - fans of the OS Plan 9 from Bell Labs
 help / color / mirror / Atom feed
From: Steven Stallion <sstallion@gmail.com>
To: 9fans@9fans.net
Subject: [9fans] gdbfs
Date: Wed, 18 Dec 2013 23:12:54 -0600	[thread overview]
Message-ID: <CAGGHmKHw5qPHqYw1QHXbYYdgXpYk0LCQEf9Rfi85+yV+p2isdw@mail.gmail.com> (raw)

[-- Attachment #1: Type: text/plain, Size: 1323 bytes --]

Evening 9fans,

While working on the Chromebook (nee exynos) port I ended up in a
situation where I needed to use a more sophisticated JTAG debugger to
find an issue. I ended up grabbing a RealView ICE since they are
relatively cheap on eBay (around 500.00USD) compared to other models
capable of debugging Cortex-A15 cores. Older firmware revisions of the
 RVI support the remote GDB protocol (in addition to the closed RDDI
protocol). I've written a simple 9P file server that translates
memory/register accesses to remote GDB targets. I haven't tried it
yet, but this should also work with OpenOCD as well.

At the moment this is little more than a toy, but it has been stable
enough for me to debug issues on the board reliably. I've added
support for ARM and i386 for now - adding additional register maps for
the other mach types is straightforward. If there is enough demand,
I'll write up a man page and submit a patch. The setup for this isn't
particularly obvious since it requires some messing about with RVI
firmware updates and downloading the right version of RVDS to setup
the board, so a wiki page is deserved as well.

For now, you can find the source in my contrib directory on sources:
/n/sources/contrib/stallion/src/gdbfs/

(Obligatory screenshot attached)

Cheers,

Steve

[-- Attachment #2: gdbfs.png --]
[-- Type: image/png, Size: 56093 bytes --]

             reply	other threads:[~2013-12-19  5:12 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-12-19  5:12 Steven Stallion [this message]
2013-12-19  5:15 ` Shane Morris
2013-12-19  8:38 ` Gorka Guardiola Muzquiz
2013-12-19 15:24   ` Steven Stallion
2014-03-15 11:19 ` Alex Ivanov
2014-03-15 16:20   ` Steven Stallion

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=CAGGHmKHw5qPHqYw1QHXbYYdgXpYk0LCQEf9Rfi85+yV+p2isdw@mail.gmail.com \
    --to=sstallion@gmail.com \
    --cc=9fans@9fans.net \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).