National Semiconductor Geode CS5530
-----------------------------------

The CS5530 has two modes - one is a native PCI mode with an AC97 audio
mixer and the other is Sound Blaster 16 Emulation.

The Geode systems with XpressROM bios work properly with full interrupt
processing. If your machine has Award or AMI bios you may have problems.
Install the OSS drivers and run the /usr/lib/oss/osstest program and
if you get proper audio then it means that the audio chip is working in
interrupt mode. However if the osstest program gives I/O errors or timeout
then it means you need to enable software polling. This can be done by
running soundconf, then select Configuration Options (Options.cfg) and
then select geode_poll_mode and set it to 1. Save the configuration and
exit and now run soundon and then the osstest program should succeed.

Enabling SB16 compatibility mode
--------------------------------

To get MIDI and FM synth support you need to enable the SB16 compatibility
mode. To do this:
1) Run soundconf, select Remove option and remove the NS Geode device
2) Select the Add option and from the list of devices select SB16
3) Save the configuration and exit.

You will have to cold start the machine (power cycle) if you had the
native PCI mode (Geode CS5530) driver configured previously. This step
is required to reset the hardware.


Enabling Virtual Mixer devices
------------------------------

Under Linux, the Virtual Mixer devices are disabled by default because
of processor speed issues but this can be re-enabled by running soundconf,
selecting Configuration Options and selecting softoss_disable and setting
it to 0