This can be turned off by ohci1394's module parameter phys_dma=0.
The alternative firewire-ohci driver in drivers/firewire uses filtered physical
-DMA, hence is not yet suitable for remote debugging.
+DMA by default, which is more secure but not suitable for remote debugging.
+Compile the driver with CONFIG_FIREWIRE_OHCI_REMOTE_DMA (Kernel hacking menu:
+Remote debugging over FireWire with firewire-ohci) to get unfiltered physical
+DMA.
-Because ohci1394 depends on the PCI enumeration to be completed, an
-initialization routine which runs pretty early (long before console_init()
-which makes the printk buffer appear on the console can be called) was written.
+Because ohci1394 and firewire-ohci depend on the PCI enumeration to be
+completed, an initialization routine which runs pretty early has been
+implemented for x86. This routine runs long before console_init() can be
+called, i.e. before the printk buffer appears on the console.
To activate it, enable CONFIG_PROVIDE_OHCI1394_DMA_INIT (Kernel hacking menu:
-Provide code for enabling DMA over FireWire early on boot) and pass the
-parameter "ohci1394_dma=early" to the recompiled kernel on boot.
+Remote debugging over FireWire early on boot) and pass the parameter
+"ohci1394_dma=early" to the recompiled kernel on boot.
Tools
-----
Bernhard Kaindl enhanced firescope to support accessing 64-bit machines
from 32-bit firescope and vice versa:
-- ftp://ftp.suse.de/private/bk/firewire/tools/firescope-0.2.2.tar.bz2
+- http://halobates.de/firewire/firescope-0.2.2.tar.bz2
and he implemented fast system dump (alpha version - read README.txt):
-- ftp://ftp.suse.de/private/bk/firewire/tools/firedump-0.1.tar.bz2
+- http://halobates.de/firewire/firedump-0.1.tar.bz2
There is also a gdb proxy for firewire which allows to use gdb to access
data which can be referenced from symbols found by gdb in vmlinux:
-- ftp://ftp.suse.de/private/bk/firewire/tools/fireproxy-0.33.tar.bz2
+- http://halobates.de/firewire/fireproxy-0.33.tar.bz2
The latest version of this gdb proxy (fireproxy-0.34) can communicate (not
yet stable) with kgdb over an memory-based communication module (kgdbom).
Notes
-----
-Documentation and specifications: ftp://ftp.suse.de/private/bk/firewire/docs
+Documentation and specifications: http://halobates.de/firewire/
FireWire is a trademark of Apple Inc. - for more information please refer to:
http://en.wikipedia.org/wiki/FireWire