diff options
| -rw-r--r-- | Documentation/power/swsusp.txt | 51 | ||||
| -rw-r--r-- | Documentation/power/video.txt | 74 | ||||
| -rw-r--r-- | kernel/power/process.c | 2 |
3 files changed, 78 insertions, 49 deletions
diff --git a/Documentation/power/swsusp.txt b/Documentation/power/swsusp.txt index b28b7f04abb..d7814a113ee 100644 --- a/Documentation/power/swsusp.txt +++ b/Documentation/power/swsusp.txt @@ -17,6 +17,11 @@ Some warnings, first. * but it will probably only crash. * * (*) suspend/resume support is needed to make it safe. + * + * If you have any filesystems on USB devices mounted before suspend, + * they won't be accessible after resume and you may lose data, as though + * you have unplugged the USB devices with mounted filesystems on them + * (see the FAQ below for details). You need to append resume=/dev/your_swap_partition to kernel command line. Then you suspend by @@ -27,19 +32,18 @@ echo shutdown > /sys/power/disk; echo disk > /sys/power/state echo platform > /sys/power/disk; echo disk > /sys/power/state +. If you have SATA disks, you'll need recent kernels with SATA suspend +support. For suspend and resume to work, make sure your disk drivers +are built into kernel -- not modules. [There's way to make +suspend/resume with modular disk drivers, see FAQ, but you probably +should not do that.] + If you want to limit the suspend image size to N bytes, do echo N > /sys/power/image_size before suspend (it is limited to 500 MB by default). -Encrypted suspend image: ------------------------- -If you want to store your suspend image encrypted with a temporary -key to prevent data gathering after resume you must compile -crypto and the aes algorithm into the kernel - modules won't work -as they cannot be loaded at resume time. - Article about goals and implementation of Software Suspend for Linux ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ @@ -333,4 +337,37 @@ init=/bin/bash, then swapon and starting suspend sequence manually usually does the trick. Then it is good idea to try with latest vanilla kernel. +Q: How can distributions ship a swsusp-supporting kernel with modular +disk drivers (especially SATA)? + +A: Well, it can be done, load the drivers, then do echo into +/sys/power/disk/resume file from initrd. Be sure not to mount +anything, not even read-only mount, or you are going to lose your +data. + +Q: How do I make suspend more verbose? + +A: If you want to see any non-error kernel messages on the virtual +terminal the kernel switches to during suspend, you have to set the +kernel console loglevel to at least 5, for example by doing + + echo 5 > /proc/sys/kernel/printk + +Q: Is this true that if I have a mounted filesystem on a USB device and +I suspend to disk, I can lose data unless the filesystem has been mounted +with "sync"? + +A: That's right. It depends on your hardware, and it could be true even for +suspend-to-RAM. In fact, even with "-o sync" you can lose data if your +programs have information in buffers they haven't written out to disk. + +If you're lucky, your hardware will support low-power modes for USB +controllers while the system is asleep. Lots of hardware doesn't, +however. Shutting off the power to a USB controller is equivalent to +unplugging all the attached devices. + +Remember that it's always a bad idea to unplug a disk drive containing a +mounted filesystem. With USB that's true even when your system is asleep! +The safest thing is to unmount all USB-based filesystems before suspending +and remount them after resuming. diff --git a/Documentation/power/video.txt b/Documentation/power/video.txt index 912bed87c75..d18a57d1a53 100644 --- a/Documentation/power/video.txt +++ b/Documentation/power/video.txt @@ -1,7 +1,7 @@ Video issues with S3 resume ~~~~~~~~~~~~~~~~~~~~~~~~~~~ - 2003-2005, Pavel Machek + 2003-2006, Pavel Machek During S3 resume, hardware needs to be reinitialized. For most devices, this is easy, and kernel driver knows how to do @@ -15,6 +15,27 @@ run normally so video card is normally initialized. It should not be problem for S1 standby, because hardware should retain its state over that. +We either have to run video BIOS during early resume, or interpret it +using vbetool later, or maybe nothing is neccessary on particular +system because video state is preserved. Unfortunately different +methods work on different systems, and no known method suits all of +them. + +Userland application called s2ram has been developed; it contains long +whitelist of systems, and automatically selects working method for a +given system. It can be downloaded from CVS at +www.sf.net/projects/suspend . If you get a system that is not in the +whitelist, please try to find a working solution, and submit whitelist +entry so that work does not need to be repeated. + +Currently, VBE_SAVE method (6 below) works on most +systems. Unfortunately, vbetool only runs after userland is resumed, +so it makes debugging of early resume problems +hard/impossible. Methods that do not rely on userland are preferable. + +Details +~~~~~~~ + There are a few types of systems where video works after S3 resume: (1) systems where video state is preserved over S3. @@ -104,6 +125,7 @@ HP NX7000 ??? (*) HP Pavilion ZD7000 vbetool post needed, need open-source nv driver for X HP Omnibook XE3 athlon version none (1) HP Omnibook XE3GC none (1), video is S3 Savage/IX-MV +HP Omnibook 5150 none (1), (S1 also works OK) IBM TP T20, model 2647-44G none (1), video is S3 Inc. 86C270-294 Savage/IX-MV, vesafb gets "interesting" but X work. IBM TP A31 / Type 2652-M5G s3_mode (3) [works ok with BIOS 1.04 2002-08-23, but not at all with BIOS 1.11 2004-11-05 :-(] IBM TP R32 / Type 2658-MMG none (1) @@ -120,18 +142,24 @@ IBM ThinkPad T42p (2373-GTG) s3_bios (2) IBM TP X20 ??? (*) IBM TP X30 s3_bios (2) IBM TP X31 / Type 2672-XXH none (1), use radeontool (http://fdd.com/software/radeon/) to turn off backlight. -IBM TP X32 none (1), but backlight is on and video is trashed after long suspend +IBM TP X32 none (1), but backlight is on and video is trashed after long suspend. s3_bios,s3_mode (4) works too. Perhaps that gets better results? IBM Thinkpad X40 Type 2371-7JG s3_bios,s3_mode (4) +IBM TP 600e none(1), but a switch to console and back to X is needed Medion MD4220 ??? (*) Samsung P35 vbetool needed (6) -Sharp PC-AR10 (ATI rage) none (1) +Sharp PC-AR10 (ATI rage) none (1), backlight does not switch off Sony Vaio PCG-C1VRX/K s3_bios (2) Sony Vaio PCG-F403 ??? (*) +Sony Vaio PCG-GRT995MP none (1), works with 'nv' X driver +Sony Vaio PCG-GR7/K none (1), but needs radeonfb, use radeontool (http://fdd.com/software/radeon/) to turn off backlight. Sony Vaio PCG-N505SN ??? (*) Sony Vaio vgn-s260 X or boot-radeon can init it (5) +Sony Vaio vgn-S580BH vga=normal, but suspend from X. Console will be blank unless you return to X. +Sony Vaio vgn-FS115B s3_bios (2),s3_mode (4) Toshiba Libretto L5 none (1) -Toshiba Satellite 4030CDT s3_mode (3) -Toshiba Satellite 4080XCDT s3_mode (3) +Toshiba Portege 3020CT s3_mode (3) +Toshiba Satellite 4030CDT s3_mode (3) (S1 also works OK) +Toshiba Satellite 4080XCDT s3_mode (3) (S1 also works OK) Toshiba Satellite 4090XCDT ??? (*) Toshiba Satellite P10-554 s3_bios,s3_mode (4)(****) Toshiba M30 (2) xor X with nvidia driver using internal AGP @@ -151,39 +179,3 @@ Asus A7V8X nVidia RIVA TNT2 model 64 s3_bios,s3_mode (4) (***) To be tested with a newer kernel. (****) Not with SMP kernel, UP only. - -VBEtool details -~~~~~~~~~~~~~~~ -(with thanks to Carl-Daniel Hailfinger) - -First, boot into X and run the following script ONCE: -#!/bin/bash -statedir=/root/s3/state -mkdir -p $statedir -chvt 2 -sleep 1 -vbetool vbestate save >$statedir/vbe - - -To suspend and resume properly, call the following script as root: -#!/bin/bash -statedir=/root/s3/state -curcons=`fgconsole` -fuser /dev/tty$curcons 2>/dev/null|xargs ps -o comm= -p|grep -q X && chvt 2 -cat /dev/vcsa >$statedir/vcsa -sync -echo 3 >/proc/acpi/sleep -sync -vbetool post -vbetool vbestate restore <$statedir/vbe -cat $statedir/vcsa >/dev/vcsa -rckbd restart -chvt $[curcons%6+1] -chvt $curcons - - -Unless you change your graphics card or other hardware configuration, -the state once saved will be OK for every resume afterwards. -NOTE: The "rckbd restart" command may be different for your -distribution. Simply replace it with the command you would use to -set the fonts on screen. diff --git a/kernel/power/process.c b/kernel/power/process.c index 28de118f7a0..02a1b3a9fa9 100644 --- a/kernel/power/process.c +++ b/kernel/power/process.c @@ -83,7 +83,7 @@ int freeze_processes(void) yield(); /* Yield is okay here */ if (todo && time_after(jiffies, start_time + TIMEOUT)) { printk( "\n" ); - printk(KERN_ERR " stopping tasks failed (%d tasks remaining)\n", todo ); + printk(KERN_ERR " stopping tasks timed out (%d tasks remaining)\n", todo ); break; } } while(todo); |