1===========================
2Video issues with S3 resume
3===========================
4
52003-2006, Pavel Machek
6
7During S3 resume, hardware needs to be reinitialized. For most
8devices, this is easy, and kernel driver knows how to do
9it. Unfortunately there's one exception: video card. Those are usually
10initialized by BIOS, and kernel does not have enough information to
11boot video card. (Kernel usually does not even contain video card
12driver -- vesafb and vgacon are widely used).
13
14This is not problem for swsusp, because during swsusp resume, BIOS is
15run normally so video card is normally initialized. It should not be
16problem for S1 standby, because hardware should retain its state over
17that.
18
19We either have to run video BIOS during early resume, or interpret it
20using vbetool later, or maybe nothing is necessary on particular
21system because video state is preserved. Unfortunately different
22methods work on different systems, and no known method suits all of
23them.
24
25Userland application called s2ram has been developed; it contains long
26whitelist of systems, and automatically selects working method for a
27given system. It can be downloaded from CVS at
28www.sf.net/projects/suspend . If you get a system that is not in the
29whitelist, please try to find a working solution, and submit whitelist
30entry so that work does not need to be repeated.
31
32Currently, VBE_SAVE method (6 below) works on most
33systems. Unfortunately, vbetool only runs after userland is resumed,
34so it makes debugging of early resume problems
35hard/impossible. Methods that do not rely on userland are preferable.
36
37Details
38~~~~~~~
39
40There are a few types of systems where video works after S3 resume:
41
42(1) systems where video state is preserved over S3.
43
44(2) systems where it is possible to call the video BIOS during S3
45    resume. Unfortunately, it is not correct to call the video BIOS at
46    that point, but it happens to work on some machines. Use
47    acpi_sleep=s3_bios.
48
49(3) systems that initialize video card into vga text mode and where
50    the BIOS works well enough to be able to set video mode. Use
51    acpi_sleep=s3_mode on these.
52
53(4) on some systems s3_bios kicks video into text mode, and
54    acpi_sleep=s3_bios,s3_mode is needed.
55
56(5) radeon systems, where X can soft-boot your video card. You'll need
57    a new enough X, and a plain text console (no vesafb or radeonfb). See
58    http://www.doesi.gmxhome.de/linux/tm800s3/s3.html for more information.
59    Alternatively, you should use vbetool (6) instead.
60
61(6) other radeon systems, where vbetool is enough to bring system back
62    to life. It needs text console to be working. Do vbetool vbestate
63    save > /tmp/delme; echo 3 > /proc/acpi/sleep; vbetool post; vbetool
64    vbestate restore < /tmp/delme; setfont <whatever>, and your video
65    should work.
66
67(7) on some systems, it is possible to boot most of kernel, and then
68    POSTing bios works. Ole Rohne has patch to do just that at
69    http://dev.gentoo.org/~marineam/patch-radeonfb-2.6.11-rc2-mm2.
70
71(8) on some systems, you can use the video_post utility and or
72    do echo 3 > /sys/power/state  && /usr/sbin/video_post - which will
73    initialize the display in console mode. If you are in X, you can switch
74    to a virtual terminal and back to X using  CTRL+ALT+F1 - CTRL+ALT+F7 to get
75    the display working in graphical mode again.
76
77Now, if you pass acpi_sleep=something, and it does not work with your
78bios, you'll get a hard crash during resume. Be careful. Also it is
79safest to do your experiments with plain old VGA console. The vesafb
80and radeonfb (etc) drivers have a tendency to crash the machine during
81resume.
82
83You may have a system where none of above works. At that point you
84either invent another ugly hack that works, or write proper driver for
85your video card (good luck getting docs :-(). Maybe suspending from X
86(proper X, knowing your hardware, not XF68_FBcon) might have better
87chance of working.
88
89Table of known working notebooks:
90
91
92=============================== ===============================================
93Model                           hack (or "how to do it")
94=============================== ===============================================
95Acer Aspire 1406LC		ole's late BIOS init (7), turn off DRI
96Acer TM 230			s3_bios (2)
97Acer TM 242FX			vbetool (6)
98Acer TM C110			video_post (8)
99Acer TM C300                    vga=normal (only suspend on console, not in X),
100				vbetool (6) or video_post (8)
101Acer TM 4052LCi		        s3_bios (2)
102Acer TM 636Lci			s3_bios,s3_mode (4)
103Acer TM 650 (Radeon M7)		vga=normal plus boot-radeon (5) gets text
104				console back
105Acer TM 660			??? [#f1]_
106Acer TM 800			vga=normal, X patches, see webpage (5)
107				or vbetool (6)
108Acer TM 803			vga=normal, X patches, see webpage (5)
109				or vbetool (6)
110Acer TM 803LCi			vga=normal, vbetool (6)
111Arima W730a			vbetool needed (6)
112Asus L2400D                     s3_mode (3) [#f2]_ (S1 also works OK)
113Asus L3350M (SiS 740)           (6)
114Asus L3800C (Radeon M7)		s3_bios (2) (S1 also works OK)
115Asus M6887Ne			vga=normal, s3_bios (2), use radeon driver
116				instead of fglrx in x.org
117Athlon64 desktop prototype	s3_bios (2)
118Compal CL-50			??? [#f1]_
119Compaq Armada E500 - P3-700     none (1) (S1 also works OK)
120Compaq Evo N620c		vga=normal, s3_bios (2)
121Dell 600m, ATI R250 Lf		none (1), but needs xorg-x11-6.8.1.902-1
122Dell D600, ATI RV250            vga=normal and X, or try vbestate (6)
123Dell D610			vga=normal and X (possibly vbestate (6) too,
124				but not tested)
125Dell Inspiron 4000		??? [#f1]_
126Dell Inspiron 500m		??? [#f1]_
127Dell Inspiron 510m		???
128Dell Inspiron 5150		vbetool needed (6)
129Dell Inspiron 600m		??? [#f1]_
130Dell Inspiron 8200		??? [#f1]_
131Dell Inspiron 8500		??? [#f1]_
132Dell Inspiron 8600		??? [#f1]_
133eMachines athlon64 machines	vbetool needed (6) (someone please get
134				me model #s)
135HP NC6000			s3_bios, may not use radeonfb (2);
136				or vbetool (6)
137HP NX7000			??? [#f1]_
138HP Pavilion ZD7000		vbetool post needed, need open-source nv
139				driver for X
140HP Omnibook XE3	athlon version	none (1)
141HP Omnibook XE3GC		none (1), video is S3 Savage/IX-MV
142HP Omnibook XE3L-GF		vbetool (6)
143HP Omnibook 5150		none (1), (S1 also works OK)
144IBM TP T20, model 2647-44G	none (1), video is S3 Inc. 86C270-294
145				Savage/IX-MV, vesafb gets "interesting"
146				but X work.
147IBM TP A31 / Type 2652-M5G      s3_mode (3) [works ok with
148				BIOS 1.04 2002-08-23, but not at all with
149				BIOS 1.11 2004-11-05 :-(]
150IBM TP R32 / Type 2658-MMG      none (1)
151IBM TP R40 2722B3G		??? [#f1]_
152IBM TP R50p / Type 1832-22U     s3_bios (2)
153IBM TP R51			none (1)
154IBM TP T30	236681A		??? [#f1]_
155IBM TP T40 / Type 2373-MU4      none (1)
156IBM TP T40p			none (1)
157IBM TP R40p			s3_bios (2)
158IBM TP T41p			s3_bios (2), switch to X after resume
159IBM TP T42			s3_bios (2)
160IBM ThinkPad T42p (2373-GTG)	s3_bios (2)
161IBM TP X20			??? [#f1]_
162IBM TP X30			s3_bios, s3_mode (4)
163IBM TP X31 / Type 2672-XXH      none (1), use radeontool
164				(http://fdd.com/software/radeon/) to
165				turn off backlight.
166IBM TP X32			none (1), but backlight is on and video is
167				trashed after long suspend. s3_bios,
168				s3_mode (4) works too. Perhaps that gets
169				better results?
170IBM Thinkpad X40 Type 2371-7JG  s3_bios,s3_mode (4)
171IBM TP 600e			none(1), but a switch to console and
172				back to X is needed
173Medion MD4220			??? [#f1]_
174Samsung P35			vbetool needed (6)
175Sharp PC-AR10 (ATI rage)	none (1), backlight does not switch off
176Sony Vaio PCG-C1VRX/K		s3_bios (2)
177Sony Vaio PCG-F403		??? [#f1]_
178Sony Vaio PCG-GRT995MP		none (1), works with 'nv' X driver
179Sony Vaio PCG-GR7/K		none (1), but needs radeonfb, use
180				radeontool (http://fdd.com/software/radeon/)
181				to turn off backlight.
182Sony Vaio PCG-N505SN		??? [#f1]_
183Sony Vaio vgn-s260		X or boot-radeon can init it (5)
184Sony Vaio vgn-S580BH		vga=normal, but suspend from X. Console will
185				be blank unless you return to X.
186Sony Vaio vgn-FS115B		s3_bios (2),s3_mode (4)
187Toshiba Libretto L5		none (1)
188Toshiba Libretto 100CT/110CT    vbetool (6)
189Toshiba Portege 3020CT		s3_mode (3)
190Toshiba Satellite 4030CDT	s3_mode (3) (S1 also works OK)
191Toshiba Satellite 4080XCDT      s3_mode (3) (S1 also works OK)
192Toshiba Satellite 4090XCDT      ??? [#f1]_
193Toshiba Satellite P10-554       s3_bios,s3_mode (4)[#f3]_
194Toshiba M30                     (2) xor X with nvidia driver using internal AGP
195Uniwill 244IIO			??? [#f1]_
196=============================== ===============================================
197
198Known working desktop systems
199~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
200
201=================== ============================= ========================
202Mainboard	    Graphics card                 hack (or "how to do it")
203=================== ============================= ========================
204Asus A7V8X	    nVidia RIVA TNT2 model 64	  s3_bios,s3_mode (4)
205=================== ============================= ========================
206
207
208.. [#f1] from https://wiki.ubuntu.com/HoaryPMResults, not sure
209         which options to use. If you know, please tell me.
210
211.. [#f2] To be tested with a newer kernel.
212
213.. [#f3] Not with SMP kernel, UP only.
214