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diff --git a/Documentation/fb/intel810.txt b/Documentation/fb/intel810.txt new file mode 100644 index 000000000..a8e9f5bca --- /dev/null +++ b/Documentation/fb/intel810.txt @@ -0,0 +1,278 @@ +Intel 810/815 Framebuffer driver + Tony Daplas <adaplas@pol.net> + http://i810fb.sourceforge.net + + March 17, 2002 + + First Released: July 2001 + Last Update: September 12, 2005 +================================================================ + +A. Introduction + + This is a framebuffer driver for various Intel 810/815 compatible + graphics devices. These include: + + Intel 810 + Intel 810E + Intel 810-DC100 + Intel 815 Internal graphics only, 100Mhz FSB + Intel 815 Internal graphics only + Intel 815 Internal graphics and AGP + +B. Features + + - Choice of using Discrete Video Timings, VESA Generalized Timing + Formula, or a framebuffer specific database to set the video mode + + - Supports a variable range of horizontal and vertical resolution and + vertical refresh rates if the VESA Generalized Timing Formula is + enabled. + + - Supports color depths of 8, 16, 24 and 32 bits per pixel + + - Supports pseudocolor, directcolor, or truecolor visuals + + - Full and optimized hardware acceleration at 8, 16 and 24 bpp + + - Robust video state save and restore + + - MTRR support + + - Utilizes user-entered monitor specifications to automatically + calculate required video mode parameters. + + - Can concurrently run with xfree86 running with native i810 drivers + + - Hardware Cursor Support + + - Supports EDID probing either by DDC/I2C or through the BIOS + +C. List of available options + + a. "video=i810fb" + enables the i810 driver + + Recommendation: required + + b. "xres:<value>" + select horizontal resolution in pixels. (This parameter will be + ignored if 'mode_option' is specified. See 'o' below). + + Recommendation: user preference + (default = 640) + + c. "yres:<value>" + select vertical resolution in scanlines. If Discrete Video Timings + is enabled, this will be ignored and computed as 3*xres/4. (This + parameter will be ignored if 'mode_option' is specified. See 'o' + below) + + Recommendation: user preference + (default = 480) + + d. "vyres:<value>" + select virtual vertical resolution in scanlines. If (0) or none + is specified, this will be computed against maximum available memory. + + Recommendation: do not set + (default = 480) + + e. "vram:<value>" + select amount of system RAM in MB to allocate for the video memory + + Recommendation: 1 - 4 MB. + (default = 4) + + f. "bpp:<value>" + select desired pixel depth + + Recommendation: 8 + (default = 8) + + g. "hsync1/hsync2:<value>" + select the minimum and maximum Horizontal Sync Frequency of the + monitor in kHz. If using a fixed frequency monitor, hsync1 must + be equal to hsync2. If EDID probing is successful, these will be + ignored and values will be taken from the EDID block. + + Recommendation: check monitor manual for correct values + (default = 29/30) + + h. "vsync1/vsync2:<value>" + select the minimum and maximum Vertical Sync Frequency of the monitor + in Hz. You can also use this option to lock your monitor's refresh + rate. If EDID probing is successful, these will be ignored and values + will be taken from the EDID block. + + Recommendation: check monitor manual for correct values + (default = 60/60) + + IMPORTANT: If you need to clamp your timings, try to give some + leeway for computational errors (over/underflows). Example: if + using vsync1/vsync2 = 60/60, make sure hsync1/hsync2 has at least + a 1 unit difference, and vice versa. + + i. "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). The default + offset (16 MB for a 64 MB aperture, 8 MB for a 32 MB aperture) will + avoid XFree86's usage and allows up to 7 MB/15 MB of framebuffer + memory. Depending on your usage, adjust the value up or down + (0 for maximum usage, 31/63 MB for the least amount). Note, an + arbitrary setting may conflict with XFree86. + + Recommendation: do not set + (default = 8 or 16 MB) + + j. "accel" + enable text acceleration. This can be enabled/reenabled anytime + by using 'fbset -accel true/false'. + + Recommendation: enable + (default = not set) + + k. "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 i810/i815 because of 'shared memory'. + + Recommendation: do not set + (default = not set) + + l. "extvga" + if specified, secondary/external VGA output will always be enabled. + Useful if the BIOS turns off the VGA port when no monitor is attached. + The external VGA monitor can then be attached without rebooting. + + Recommendation: do not set + (default = not set) + + m. "sync" + Forces the hardware engine to do a "sync" or wait for the hardware + to finish before starting another instruction. This will produce a + more stable setup, but will be slower. + + Recommendation: do not set + (default = not set) + + n. "dcolor" + Use directcolor visual instead of truecolor for pixel depths greater + than 8 bpp. Useful for color tuning, such as gamma control. + + Recommendation: do not set + (default = not set) + + o. <xres>x<yres>[-<bpp>][@<refresh>] + The driver will now accept specification of boot mode option. If this + is specified, the options 'xres' and 'yres' will be ignored. See + Documentation/fb/modedb.txt for usage. + +D. Kernel booting + +Separate each option/option-pair by commas (,) and the option from its value +with a colon (:) as in the following: + +video=i810fb:option1,option2:value2 + +Sample Usage +------------ + +In /etc/lilo.conf, add the line: + +append="video=i810fb:vram:2,xres:1024,yres:768,bpp:8,hsync1:30,hsync2:55, \ + vsync1:50,vsync2:85,accel,mtrr" + +This will initialize the framebuffer to 1024x768 at 8bpp. The framebuffer +will use 2 MB of System RAM. MTRR support will be enabled. The refresh rate +will be computed based on the hsync1/hsync2 and vsync1/vsync2 values. + +IMPORTANT: +You must include hsync1, hsync2, vsync1 and vsync2 to enable video modes +better than 640x480 at 60Hz. HOWEVER, if your chipset/display combination +supports I2C and has an EDID block, you can safely exclude hsync1, hsync2, +vsync1 and vsync2 parameters. These parameters will be taken from the EDID +block. + +E. 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 i810fb vram=2 xres=1024 bpp=8 hsync1=30 hsync2=55 vsync1=50 \ + vsync2=85 accel=1 mtrr=1 + +Or just add the following to a configuration file in /etc/modprobe.d/ + + options i810fb vram=2 xres=1024 bpp=16 hsync1=30 hsync2=55 vsync1=50 \ + vsync2=85 accel=1 mtrr=1 + +and just do a + + modprobe i810fb + + +F. Setup + + a. Do your usual method of configuring the kernel. + + make menuconfig/xconfig/config + + b. Under "Code maturity level options" enable "Prompt for development + and/or incomplete code/drivers". + + c. Enable agpgart support for the Intel 810/815 on-board graphics. + This is required. The option is under "Character Devices". + + d. Under "Graphics Support", select "Intel 810/815" either statically + or as a module. Choose "use VESA Generalized Timing Formula" if + you need to maximize the capability of your display. To be on the + safe side, you can leave this unselected. + + e. If you want support for DDC/I2C probing (Plug and Play Displays), + set 'Enable DDC Support' to 'y'. To make this option appear, set + 'use VESA Generalized Timing Formula' to 'y'. + + f. If you want a framebuffer console, enable it under "Console + Drivers". + + g. Compile your kernel. + + h. Load the driver as described in sections D and E. + + i. Try the DirectFB (http://www.directfb.org) + the i810 gfxdriver + patch to see the chipset in action (or inaction :-). + +G. Acknowledgment: + + 1. Geert Uytterhoeven - his excellent howto and the virtual + framebuffer driver code made this possible. + + 2. Jeff Hartmann for his agpgart code. + + 3. The X developers. Insights were provided just by reading the + XFree86 source code. + + 4. Intel(c). For this value-oriented chipset driver and for + providing documentation. + + 5. Matt Sottek. His inputs and ideas helped in making some + optimizations possible. + +H. Home Page: + + A more complete, and probably updated information is provided at + http://i810fb.sourceforge.net. + +########################### +Tony + |