[linux-block.git] / Documentation / fb / intelfb.txt

Intel 830M/845G/852GM/855GM/865G/915G Framebuffer driver
================================================================

A. Introduction
	This is a framebuffer driver for various Intel 810/815 compatible
graphics devices.  These would include:

	Intel 830M
	Intel 810E845G
	Intel 852GM
	Intel 855GM
	Intel 865G
	Intel 915G

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=i810fb:option1,option2=value2

Sample Usage
------------

In /etc/lilo.conf, add the line:

append="video=intelfb: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.

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 /etc/modprobe.conf

	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
Commit	Line	Data
4ff45f51 SM	1	Intel 830M/845G/852GM/855GM/865G/915G Framebuffer driver
	2	================================================================
	3
	4	A. Introduction
	5	This is a framebuffer driver for various Intel 810/815 compatible
	6	graphics devices. These would include:
	7
	8	Intel 830M
	9	Intel 810E845G
	10	Intel 852GM
	11	Intel 855GM
	12	Intel 865G
	13	Intel 915G
	14
	15	B. List of available options
	16
	17	a. "video=intelfb"
	18	enables the intelfb driver
	19
	20	Recommendation: required
	21
	22	b. "mode=<xres>x<yres>[-<bpp>][@<refresh>]"
	23	select mode
	24
	25	Recommendation: user preference
	26	(default = 1024x768-32@70)
	27
	28	c. "vram=<value>"
	29	select amount of system RAM in MB to allocate for the video memory
	30	if not enough RAM was already allocated by the BIOS.
	31
	32	Recommendation: 1 - 4 MB.
	33	(default = 4 MB)
	34
	35	d. "voffset=<value>"
	36	select at what offset in MB of the logical memory to allocate the
	37	framebuffer memory. The intent is to avoid the memory blocks
	38	used by standard graphics applications (XFree86). Depending on your
	39	usage, adjust the value up or down, (0 for maximum usage, 63/127 MB
	40	for the least amount). Note, an arbitrary setting may conflict
	41	with XFree86.
	42
	43	Recommendation: do not set
	44	(default = 48 MB)
	45
	46	e. "accel"
	47	enable text acceleration. This can be enabled/reenabled anytime
	48	by using 'fbset -accel true/false'.
	49
	50	Recommendation: enable
	51	(default = set)
	52
	53	f. "hwcursor"
	54	enable cursor acceleration.
	55
	56	Recommendation: enable
	57	(default = set)
	58
	59	g. "mtrr"
	60	enable MTRR. This allows data transfers to the framebuffer memory
	61	to occur in bursts which can significantly increase performance.
	62	Not very helpful with the intel chips because of 'shared memory'.
	63
	64	Recommendation: set
65	(default = set)
66
67	h. "fixed"
68	disable mode switching.
69
70	Recommendation: do not set
71	(default = not set)
72
73	The binary parameters can be unset with a "no" prefix, example "noaccel".
74	The default parameter (not named) is the mode.
75
76	C. Kernel booting
77
78	Separate each option/option-pair by commas (,) and the option from its value
79	with an equals sign (=) as in the following:
80
81	video=i810fb:option1,option2=value2
82
83	Sample Usage
84	------------
85
86	In /etc/lilo.conf, add the line:
87
88	append="video=intelfb:800x600-32@75,accel,hwcursor,vram=8"
89
90	This will initialize the framebuffer to 800x600 at 32bpp and 75Hz. The
91	framebuffer will use 8 MB of System RAM. hw acceleration of text and cursor
92	will be enabled.
93
94	D. Module options
95
96	The module parameters are essentially similar to the kernel
97	parameters. The main difference is that you need to include a Boolean value
98	(1 for TRUE, and 0 for FALSE) for those options which don't need a value.
99
100	Example, to enable MTRR, include "mtrr=1".
101
102	Sample Usage
103	------------
104
105	Using the same setup as described above, load the module like this:
106
107	modprobe intelfb mode=800x600-32@75 vram=8 accel=1 hwcursor=1
108
109	Or just add the following to /etc/modprobe.conf
110
111	options intelfb mode=800x600-32@75 vram=8 accel=1 hwcursor=1
112
113	and just do a
114
115	modprobe intelfb
116
117
118	E. Acknowledgment:
119
120	1. Geert Uytterhoeven - his excellent howto and the virtual
121	framebuffer driver code made this possible.
122
123	2. Jeff Hartmann for his agpgart code.
124
125	3. David Dawes for his original kernel 2.4 code.
126
127	4. The X developers. Insights were provided just by reading the
128	XFree86 source code.
129
130	5. Antonino A. Daplas for his inspiring i810fb driver.
131
132	6. Andrew Morton for his kernel patches maintenance.
133
134	###########################
135	Sylvain