The chipset works perfectly with latest XFree 4.2.0 release. If you use
the cvs version you also have acceleration (I can watch DVD's smoothly).

Here you are my config file (I use redhat rawhide XFree). Enjoy.

---------------------------------------------------------------
# XFree86 4.2.0 configuration generated by Xconfigurator 4.10.7

Section "ServerLayout"
Identifier "XFree86 Configured"
Screen 0 "Screen0" 0 0
InputDevice "Mouse0" "CorePointer"
InputDevice "MouseUSB" "SendCoreEvents"
InputDevice "Keyboard0" "CoreKeyboard"
EndSection

# Red Hat Linux 6.0 and later use the xfs font server for improved
# interactive performance

Section "Files"
FontPath "unix/:7100"
EndSection

# Module loading section

Section "Module"
Load "dbe" # Double-buffering
Load "GLcore" # OpenGL support
Load "dri" # Direct rendering infrastructure
Load "glx" # OpenGL X protocol interface
Load "extmod" # Misc. required extensions
Load "v4l" # Video4Linux
# Load "record" # X event recorder
# You only need the following two modules if you do not use xfs.
# Load "freetype" # TrueType font handler
# Load "type1" # Adobe Type 1 font handler
EndSection

Section "InputDevice"
Identifier "Keyboard0"
Driver "keyboard"
Option "XkbLayout" "us"
EndSection

Section "InputDevice"
Identifier "Mouse0"
Driver "mouse"
Option "Device" "/dev/psaux"
Option "Protocol" "IMPS/2"
Option "Emulate3Buttons" "on"
Option "ZAxisMapping" "4 5"
EndSection

Section "InputDevice"
Identifier "MouseUSB"
Driver "mouse"
Option "Device" "/dev/input/mice"
Option "Protocol" "IMPS/2"
Option "Emulate3Buttons" "no"
Option "ZAxisMapping" "4 5"
EndSection

Section "Monitor"
Identifier "Generic Laptop Display Panel 1024x768"
VendorName "Unknown"
ModelName "Unknown"
HorizSync 31.5-48.5
VertRefresh 40-70
Option "dpms"
EndSection

Section "Device"
Identifier "Trident CyberBladeXPm"
Driver "trident"
chipset "cyberbladeXPAi1"
Option "CyberStretch"
Option "ShadowFB" "on"
VideoRam 16384
VendorName "Toshiba"
BoardName "CyberBlade XP"
#BusId "PCI:1:0:0"
EndSection

Section "Device"
Identifier "VesaDevice"
Driver "vesa"
Option "shadowfb"
EndSection

Section "Device"
Identifier "Linux Frame Buffer"
Driver "fbdev"
BoardName "Unknown"
EndSection

Section "Screen"
Identifier "Screen0"
Device "Trident CyberBladeXPm"
# Device "VesaDevice"
Monitor "Generic Laptop Display Panel 1024x768"
DefaultDepth 16
Subsection "Display"
Depth 24
Modes "1024x768"
# Modes "1600x1200" "1280x1024" "1152x864" "1024x768"
EndSubSection
Subsection "Display"
Depth 16
Modes "1024x768"
# Modes "1600x1200" "1280x1024" "1152x864" "1024x768"
EndSubSection
EndSection

Section "DRI"
Mode 0666
EndSection