mirror of https://gitee.com/openkylin/linux.git
273 lines
7.9 KiB
Plaintext
273 lines
7.9 KiB
Plaintext
Intel 810/815 Framebuffer driver
|
|
Tony Daplas <adaplas@pol.net>
|
|
http://i810fb.sourceforge.net
|
|
|
|
March 17, 2002
|
|
|
|
First Released: July 2001
|
|
================================================================
|
|
|
|
A. Introduction
|
|
This is a framebuffer driver for various Intel 810/815 compatible
|
|
graphics devices. These would 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
|
|
|
|
C. List of available options
|
|
|
|
a. "video=i810fb"
|
|
enables the i810 driver
|
|
|
|
Recommendation: required
|
|
|
|
b. "xres:<value>"
|
|
select horizontal resolution in pixels
|
|
|
|
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.
|
|
|
|
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 a using a fixed frequency monitor, hsync1 must
|
|
be equal to hsync2.
|
|
|
|
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.
|
|
|
|
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 64MB aperture, 8 MB for a 32MB aperture) will
|
|
avoid XFree86's usage and allows up to 7MB/15MB 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)
|
|
|
|
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.
|
|
|
|
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 /etc/modprobe.conf
|
|
|
|
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 Options", enable "Prompt for experimental/
|
|
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 GTF for video timings" 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 a framebuffer console, enable it under "Console
|
|
Drivers"
|
|
|
|
f. Compile your kernel.
|
|
|
|
g. Load the driver as described in section D and E.
|
|
|
|
Optional:
|
|
h. If you are going to run XFree86 with its native drivers, the
|
|
standard XFree86 4.1.0 and 4.2.0 drivers should work as is.
|
|
However, there's a bug in the XFree86 i810 drivers. It attempts
|
|
to use XAA even when switched to the console. This will crash
|
|
your server. I have a fix at this site:
|
|
|
|
http://i810fb.sourceforge.net.
|
|
|
|
You can either use the patch, or just replace
|
|
|
|
/usr/X11R6/lib/modules/drivers/i810_drv.o
|
|
|
|
with the one provided at the website.
|
|
|
|
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
|
|
|