Embedded Linux Conference Europe 2011 | Presentations

Efficient JTAG-Based Linux Kernel Debugging

High-end multimedia appliances now often run embedded SMP-Linux on multicore-SoC and integrate system-intrusive middle-ware like Android. Kernel Debuggers have become very sensible tools during porting and bringup of those software stacks. Additionally, JTAG-based debuggers becomes more democratic in terms of cost and availability while allowing extended early stage and crash condition debugging. We present a solution to improve JTAG-based debugging of the Linux kernel. We propose an efficient interface to retrieve the needed information, regardless of the kernel version, boot arguments, build options or the execution context. This interface requires no runtime code and can remain in production kernels. Moreover it doesn't require heavy breakpointing to maintain an accurate view of the system, which preserves the user experience in gdb and the real-time constraints of the target system. Attendees are developers who are looking for, or wish to contribute to a standard interface in the Linux kernel for debugging through JTAG.

Marc Titinger

Marc graduated in Computer Science from the University of Grenoble,France in 1998 and joined DIGIGRAM-S.A to write DSP-software and Drivers, in peculiar for Linux/ALSA. He's been involved in software architecture and design of many PCI or Ethernet-based audio products. He's adapted or written Linux drivers for different kinds of peripherals on ARM-SoCs, including LCD display, audio codecs, GPIO interface and mutimedia timers to achieve fast wake-up latency of multimedia layers. More recently I've been dealing with Linux system analysis, and optimization on products for the broadcasting industry. He is now part of the STMicroelectronics expertise center that provides Device Software Optimization and Debugging solutions to ST's Home Entertainment Division in peculiar, which products power many of today's set-top-boxes and high-end smart-phones. Currently Marc is in charge of ST's Linux Kernel Debugger that provides Linux-aware debugging through JTAG for those SoCs.