Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / Documentation / fb / tridentfb.txt

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+Tridentfb is a framebuffer driver for some Trident chip based cards.
+
+The following list of chips is thought to be supported although not all are
+tested:
+
+those from the TGUI series 9440/96XX and with Cyber in their names
+those from the Image series and with Cyber in their names
+those with Blade in their names (Blade3D,CyberBlade...)
+the newer CyberBladeXP family
+
+All families are accelerated. Only PCI/AGP based cards are supported,
+none of the older Tridents.
+The driver supports 8, 16 and 32 bits per pixel depths.
+The TGUI family requires a line length to be power of 2 if acceleration
+is enabled. This means that range of possible resolutions and bpp is
+limited comparing to the range if acceleration is disabled (see list
+of parameters below).
+
+Known bugs:
+1. The driver randomly locks up on 3DImage975 chip with acceleration
+   enabled. The same happens in X11 (Xorg).
+2. The ramdac speeds require some more fine tuning. It is possible to
+   switch resolution which the chip does not support at some depths for
+   older chips.
+
+How to use it?
+==============
+
+When booting you can pass the video parameter.
+video=tridentfb
+
+The parameters for tridentfb are concatenated with a ':' as in this example.
+
+video=tridentfb:800x600-16@75,noaccel
+
+The second level parameters that tridentfb understands are:
+
+noaccel - turns off acceleration (when it doesn't work for your card)
+
+fp     - use flat panel related stuff
+crt    - assume monitor is present instead of fp
+
+center         - for flat panels and resolutions smaller than native size center the
+         image, otherwise use
+stretch
+
+memsize - integer value in KB, use if your card's memory size is misdetected.
+         look at the driver output to see what it says when initializing.
+
+memdiff - integer value in KB, should be nonzero if your card reports
+         more memory than it actually has. For instance mine is 192K less than
+         detection says in all three BIOS selectable situations 2M, 4M, 8M.
+         Only use if your video memory is taken from main memory hence of
+         configurable size. Otherwise use memsize.
+         If in some modes which barely fit the memory you see garbage
+         at the bottom this might help by not letting change to that mode
+         anymore.
+
+nativex - the width in pixels of the flat panel.If you know it (usually 1024
+         800 or 1280) and it is not what the driver seems to detect use it.
+
+bpp    - bits per pixel (8,16 or 32)
+mode   - a mode name like 800x600-8@75 as described in
+         Documentation/fb/modedb.txt
+
+Using insane values for the above parameters will probably result in driver
+misbehaviour so take care(for instance memsize=12345678 or memdiff=23784 or
+nativex=93)
+
+Contact: jani@astechnix.ro