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diff --git a/Documentation/fb/intelfb.rst b/Documentation/fb/intelfb.rst new file mode 100644 index 000000000..e2d0903f4 --- /dev/null +++ b/Documentation/fb/intelfb.rst @@ -0,0 +1,155 @@ +============================================================= +Intel 830M/845G/852GM/855GM/865G/915G/945G Framebuffer driver +============================================================= + +A. Introduction +=============== + +This is a framebuffer driver for various Intel 8xx/9xx compatible +graphics devices. These would include: + + - Intel 830M + - Intel 845G + - Intel 852GM + - Intel 855GM + - Intel 865G + - Intel 915G + - Intel 915GM + - Intel 945G + - Intel 945GM + - Intel 945GME + - Intel 965G + - Intel 965GM + +B. List of available options +============================= + + a. "video=intelfb" + enables the intelfb driver + + Recommendation: required + + b. "mode=<xres>x<yres>[-<bpp>][@<refresh>]" + select mode + + Recommendation: user preference + (default = 1024x768-32@70) + + c. "vram=<value>" + select amount of system RAM in MB to allocate for the video memory + if not enough RAM was already allocated by the BIOS. + + Recommendation: 1 - 4 MB. + (default = 4 MB) + + d. "voffset=<value>" + select at what offset in MB of the logical memory to allocate the + framebuffer memory. The intent is to avoid the memory blocks + used by standard graphics applications (XFree86). Depending on your + usage, adjust the value up or down, (0 for maximum usage, 63/127 MB + for the least amount). Note, an arbitrary setting may conflict + with XFree86. + + Recommendation: do not set + (default = 48 MB) + + e. "accel" + enable text acceleration. This can be enabled/reenabled anytime + by using 'fbset -accel true/false'. + + Recommendation: enable + (default = set) + + f. "hwcursor" + enable cursor acceleration. + + Recommendation: enable + (default = set) + + g. "mtrr" + enable MTRR. This allows data transfers to the framebuffer memory + to occur in bursts which can significantly increase performance. + Not very helpful with the intel chips because of 'shared memory'. + + Recommendation: set + (default = set) + + h. "fixed" + disable mode switching. + + Recommendation: do not set + (default = not set) + + The binary parameters can be unset with a "no" prefix, example "noaccel". + The default parameter (not named) is the mode. + +C. Kernel booting +================= + +Separate each option/option-pair by commas (,) and the option from its value +with an equals sign (=) as in the following:: + + video=intelfb:option1,option2=value2 + +Sample Usage +------------ + +In /etc/lilo.conf, add the line:: + + append="video=intelfb:mode=800x600-32@75,accel,hwcursor,vram=8" + +This will initialize the framebuffer to 800x600 at 32bpp and 75Hz. The +framebuffer will use 8 MB of System RAM. hw acceleration of text and cursor +will be enabled. + +Remarks +------- + +If setting this parameter doesn't work (you stay in a 80x25 text-mode), +you might need to set the "vga=<mode>" parameter too - see vesafb.txt +in this directory. + + +D. Module options +================== + +The module parameters are essentially similar to the kernel +parameters. The main difference is that you need to include a Boolean value +(1 for TRUE, and 0 for FALSE) for those options which don't need a value. + +Example, to enable MTRR, include "mtrr=1". + +Sample Usage +------------ + +Using the same setup as described above, load the module like this:: + + modprobe intelfb mode=800x600-32@75 vram=8 accel=1 hwcursor=1 + +Or just add the following to a configuration file in /etc/modprobe.d/:: + + options intelfb mode=800x600-32@75 vram=8 accel=1 hwcursor=1 + +and just do a:: + + modprobe intelfb + + +E. Acknowledgment: +=================== + + 1. Geert Uytterhoeven - his excellent howto and the virtual + framebuffer driver code made this possible. + + 2. Jeff Hartmann for his agpgart code. + + 3. David Dawes for his original kernel 2.4 code. + + 4. The X developers. Insights were provided just by reading the + XFree86 source code. + + 5. Antonino A. Daplas for his inspiring i810fb driver. + + 6. Andrew Morton for his kernel patches maintenance. + +Sylvain |