This option tells the compiler NOT to build the code under
arch/powerpc with the -Werror flag (which means warnings
are treated as errors).

Only enable this if you are hitting a build failure in the
arch/powerpc code caused by a warning, and you don't feel
inclined to fix it.

This option allows you to set the stack depth that the kernel
prints in stack traces. This can be useful if your display is
too small and stack traces cause important information to
scroll off the screen.

This option will cause messages to be printed if free stack space
drops below a certain limit.

Adds code to keep track of the number of hypervisor calls made and
the amount of time spent in hypervisor calls.  Wall time spent in
each call is always calculated, and if available CPU cycles spent
are also calculated.  A directory named hcall_inst is added at the
root of the debugfs filesystem.  Within the hcall_inst directory
are files that contain CPU specific call statistics.

This option will add a small amount of overhead to all hypervisor
calls.

Adds code to keep track of the number of instructions that are
emulated by the in-kernel emulator. Counters for the various classes
of emulated instructions are available under
powerpc/emulated_instructions/ in the root of the debugfs file
system. Optionally (controlled by
powerpc/emulated_instructions/do_warn in debugfs), rate-limited
warnings can be printed to the console when instructions are
emulated.

Include in-kernel hooks for the xmon kernel monitor/debugger.
Unless you are intending to debug the kernel, say N here.
Make sure to enable also CONFIG_BOOTX_TEXT on Macs. Otherwise
nothing will appear on the screen (xmon writes directly to the
framebuffer memory).
The cmdline option 'xmon' or 'xmon=early' will drop into xmon
very early during boot. 'xmon=on' will just enable the xmon
debugger hooks.  'xmon=off' will disable the debugger hooks
if CONFIG_XMON_DEFAULT is set.
xmon will print a backtrace on the very first invocation.
'xmon=nobt' will disable this autobacktrace.

xmon is normally disabled unless booted with 'xmon=on'.
Use 'xmon=off' to disable xmon init during runtime.

Include support for disassembling in xmon. You probably want
to say Y here, unless you're building for a memory-constrained
system.

This option will show the mapping relationship between hardware irq
numbers and virtual irq numbers. The mapping is exposed via debugfs
in the file powerpc/virq_mapping.

If you don't know what this means you don't need it.

Include in-kernel support for the Abatron BDI2000 debugger.
Unless you are intending to debug the kernel with one of these
machines, say N here.

Say Y here to see progress messages from the boot firmware in text
mode. Requires either BootX or Open Firmware.

Say Y to enable some early debugging facilities that may be available
for your processor/board combination. Those facilities are hacks
intended to debug problems early during boot, this should not be
enabled in a production kernel.
Note that enabling this will also cause the kernel default log level
to be pushed to max automatically very early during boot

Use the selected console for early debugging. Careful, if you
enable debugging for the wrong type of machine your kernel
_will not boot_.

Select this to enable early debugging for a machine with a HVC
console on vterm 0.

Select this to enable early debugging for Apple G5 machines.

Select this to enable early debugging via the RTAS panel.

Select this to enable early debugging via the RTAS console.

Select this to enable early debugging for Maple.

Select this to enable early debugging for legacy iSeries. You need
to hit "Ctrl-x Ctrl-x" to see the messages on the console.

Select this to enable early debugging for PA Semi.
Output will be on UART0.

Select this to enable early debugging for Celleb with Beat.

Select this to enable early debugging for IBM 44x chips via the
inbuilt serial port.  If you enable this, ensure you set
PPC_EARLY_DEBUG_44x_PHYSLOW below to suit your target board.

Select this to enable early debugging for IBM 40x chips via the
inbuilt serial port. This works on chips with a 16550 compatible
UART. Xilinx chips with uartlite cannot use this option.

Select this to enable early debugging for Freescale chips
using a CPM-based serial port.  This assumes that the bootwrapper
has run, and set up the CPM in a particular way.

Select this to enable early debugging for Nintendo GameCube/Wii
consoles via an external USB Gecko adapter.

You probably want 0x40000200 for ebony boards and
0x40000300 for taishan

This specifies the address of the transmit descriptor
used for early debug output.  Because it is needed before
platform probing is done, all platforms selected must
share the same address.