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Based on kernel version 3.16. Page generated on 2014-08-06 21:39 EST.

1	
2	What is sisfb?
3	==============
4	
5	sisfb is a framebuffer device driver for SiS (Silicon Integrated Systems)
6	graphics chips. Supported are:
7	
8	- SiS 300 series: SiS 300/305, 540, 630(S), 730(S)
9	- SiS 315 series: SiS 315/H/PRO, 55x, (M)65x, 740, (M)661(F/M)X, (M)741(GX)
10	- SiS 330 series: SiS 330 ("Xabre"), (M)760
11	
12	
13	Why do I need a framebuffer driver?
14	===================================
15	
16	sisfb is eg. useful if you want a high-resolution text console. Besides that,
17	sisfb is required to run DirectFB (which comes with an additional, dedicated
18	driver for the 315 series).
19	
20	On the 300 series, sisfb on kernels older than 2.6.3 furthermore plays an
21	important role in connection with DRM/DRI: Sisfb manages the memory heap
22	used by DRM/DRI for 3D texture and other data. This memory management is
23	required for using DRI/DRM.
24	
25	Kernels >= around 2.6.3 do not need sisfb any longer for DRI/DRM memory
26	management. The SiS DRM driver has been updated and features a memory manager
27	of its own (which will be used if sisfb is not compiled). So unless you want
28	a graphical console, you don't need sisfb on kernels >=2.6.3.
29	
30	Sidenote: Since this seems to be a commonly made mistake: sisfb and vesafb
31	cannot be active at the same time! Do only select one of them in your kernel
32	configuration.
33	
34	
35	How are parameters passed to sisfb?
36	===================================
37	
38	Well, it depends: If compiled statically into the kernel, use lilo's append
39	statement to add the parameters to the kernel command line. Please see lilo's
40	(or GRUB's) documentation for more information. If sisfb is a kernel module,
41	parameters are given with the modprobe (or insmod) command.
42	
43	Example for sisfb as part of the static kernel: Add the following line to your
44	lilo.conf:
45	
46	     append="video=sisfb:mode:1024x768x16,mem:12288,rate:75"
47	
48	Example for sisfb as a module: Start sisfb by typing
49	
50	     modprobe sisfb mode=1024x768x16 rate=75 mem=12288
51	
52	A common mistake is that folks use a wrong parameter format when using the
53	driver compiled into the kernel. Please note: If compiled into the kernel,
54	the parameter format is video=sisfb:mode:none or video=sisfb:mode:1024x768x16
55	(or whatever mode you want to use, alternatively using any other format
56	described above or the vesa keyword instead of mode). If compiled as a module,
57	the parameter format reads mode=none or mode=1024x768x16 (or whatever mode you
58	want to use). Using a "=" for a ":" (and vice versa) is a huge difference!
59	Additionally: If you give more than one argument to the in-kernel sisfb, the
60	arguments are separated with ",". For example:
61	
62	   video=sisfb:mode:1024x768x16,rate:75,mem:12288
63	
64	
65	How do I use it?
66	================
67	
68	Preface statement: This file only covers very little of the driver's
69	capabilities and features. Please refer to the author's and maintainer's
70	website at http://www.winischhofer.net/linuxsisvga.shtml for more
71	information. Additionally, "modinfo sisfb" gives an overview over all
72	supported options including some explanation.
73	
74	The desired display mode can be specified using the keyword "mode" with
75	a parameter in one of the following formats:
76	  - XxYxDepth or
77	  - XxY-Depth or
78	  - XxY-Depth@Rate or
79	  - XxY
80	  - or simply use the VESA mode number in hexadecimal or decimal.
81	
82	For example: 1024x768x16, 1024x768-16@75, 1280x1024-16. If no depth is
83	specified, it defaults to 8. If no rate is given, it defaults to 60Hz. Depth 32
84	means 24bit color depth (but 32 bit framebuffer depth, which is not relevant
85	to the user).
86	
87	Additionally, sisfb understands the keyword "vesa" followed by a VESA mode
88	number in decimal or hexadecimal. For example: vesa=791 or vesa=0x117. Please
89	use either "mode" or "vesa" but not both.
90	
91	Linux 2.4 only: If no mode is given, sisfb defaults to "no mode" (mode=none) if
92	compiled as a module; if sisfb is statically compiled into the kernel, it
93	defaults to 800x600x8 unless CRT2 type is LCD, in which case the LCD's native
94	resolution is used. If you want to switch to a different mode, use the fbset
95	shell command.
96	
97	Linux 2.6 only: If no mode is given, sisfb defaults to 800x600x8 unless CRT2
98	type is LCD, in which case it defaults to the LCD's native resolution. If
99	you want to switch to another mode, use the stty shell command.
100	
101	You should compile in both vgacon (to boot if you remove you SiS card from
102	your system) and sisfb (for graphics mode). Under Linux 2.6, also "Framebuffer
103	console support" (fbcon) is needed for a graphical console.
104	
105	You should *not* compile-in vesafb. And please do not use the "vga=" keyword
106	in lilo's or grub's configuration file; mode selection is done using the
107	"mode" or "vesa" keywords as a parameter. See above and below.
108	
109	
110	X11
111	===
112	
113	If using XFree86 or X.org, it is recommended that you don't use the "fbdev"
114	driver but the dedicated "sis" X driver. The "sis" X driver and sisfb are
115	developed by the same person (Thomas Winischhofer) and cooperate well with
116	each other.
117	
118	
119	SVGALib
120	=======
121	
122	SVGALib, if directly accessing the hardware, never restores the screen
123	correctly, especially on laptops or if the output devices are LCD or TV.
124	Therefore, use the chipset "FBDEV" in SVGALib configuration. This will make
125	SVGALib use the framebuffer device for mode switches and restoration.
126	
127	
128	Configuration
129	=============
130	
131	(Some) accepted options:
132	
133	off      - Disable sisfb. This option is only understood if sisfb is
134	           in-kernel, not a module.
135	mem:X    - size of memory for the console, rest will be used for DRI/DRM. X
136	           is in kilobytes. On 300 series, the default is 4096, 8192 or
137		   16384 (each in kilobyte) depending on how much video ram the card
138	           has. On 315/330 series, the default is the maximum available ram
139		   (since DRI/DRM is not supported for these chipsets).
140	noaccel  - do not use 2D acceleration engine. (Default: use acceleration)
141	noypan   - disable y-panning and scroll by redrawing the entire screen.
142	           This is much slower than y-panning. (Default: use y-panning)
143	vesa:X   - selects startup videomode. X is number from 0 to 0x1FF and
144	           represents the VESA mode number (can be given in decimal or
145		   hexadecimal form, the latter prefixed with "0x").
146	mode:X   - selects startup videomode. Please see above for the format of
147	           "X".
148	
149	Boolean options such as "noaccel" or "noypan" are to be given without a
150	parameter if sisfb is in-kernel (for example "video=sisfb:noypan). If
151	sisfb is a module, these are to be set to 1 (for example "modprobe sisfb
152	noypan=1").
153	
154	--
155	Thomas Winischhofer <thomas@winischhofer.net>
156	May 27, 2004
157	
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