Template:T23 - Revision history

Wyrfel at 07:04, 15 November 2005

2005-11-15T07:04:52Z

193.237.32.199: T23 and ACPI and Suspend to RAM

2005-11-15T02:07:48Z

T23 and ACPI and Suspend to RAM

217.231.106.144 at 09:21, 10 May 2005

2005-05-10T09:21:02Z

New page

[[:Category:T23|T23]][[Category:T23]]

← Older revision		Revision as of 07:04, 15 November 2005
Line 1:		Line 1:
	[[:Category:T23\|T23]][[Category:T23]]		[[:Category:T23\|T23]][[Category:T23]]
−	~~== T23 and ACPI and Suspend to RAM ==~~
−	~~I recently bought a second-hand Thinkpad T23, Model 2647-4MG, and~~
−	~~decided to run Gentoo Linux 2.6.12-r6 on it; this is the 2005.1 release~~
−	~~on a DVD, since I have limited internet access.~~
−
−	~~The default kernel booted OK, and recognised all the devices (tho' I~~
−	~~haven't tested the modem, and I've run X-windows only briefly.)~~
−	~~However, I wanted software suspend, and I couldn't get that to work at~~
−	~~all.~~
−
−	~~The first complaint from dmesg was that ACPI wasn't enabled in the BIOS;~~
−	~~the T23 BIOS has no mention of ACPI, so I added lapic to the kernel~~
−	~~arguments and that went away. The next problem was a large number of~~
−	~~ACPI error messages, generally of the form AE_NOT_EXIST, so I got the~~
−	~~Intel iasl compiler source from their site and compiled it. It compiled~~
−	~~cleanly, and de-compiling and re-compiling the DSDT gave one Error and~~
−	~~one Remark. I fixed them as best I could, and loaded the new DSDT on~~
−	~~boot with the kernel's "Custom DSDT" option; this worked correctly, but~~
−	~~dmesg still showed a lot of ACPI error messages, including two which~~
−	~~said "Found ECDT" and "Could not use ECDT".~~
−
−	~~Rather than mess with the ECDT straightaway, I decided to upgrade to the~~
−	~~latest BIOS and Embedded Controller BIOS. The system came with (the~~
−	~~original) versions 1.12 and 1.04, so I downloaded versions 1.18 and~~
−	~~1.06a from the IBM Website. The installers come in floppy disk and~~
−	~~Windows-based versions, and I used them under Windows 2000. Mercifully~~
−	~~the re-flash worked as advertised, tho' interestingly the F12 "Select~~
−	~~Boot Device" menu changed slightly, and at first it appeared to have~~
−	~~lost the "Boot from USB" option, although that was enabled in the BIOS.~~
−	~~Apparently the menu now simply calls a USB memory stick a hard drive.~~
−	~~Anyway, boot from USB still works.~~
−
−	~~Booting into Linux then gave me no error messages, and dmesg showed that~~
−	~~the ACPI had found the ECDT and enabled the interpreter. There was also~~
−	~~a full set of ACPI entries under /proc. Although the DSDT had changed,~~
−	~~de-compiling and re-compiling with iasl showed that the error that had~~
−	~~originally bothered me was still there, so I let it be. I then loaded~~
−	~~acpid, which handles the ACPI buttons through scripts in /etc/acpi.~~
−	~~Tying Fn-f4 to "echo -n 3 >/proc/acpi/sleep" suspended the system, but~~
−	~~nothing would bring it back. Fortunately the Power Off button was still~~
−	~~functional.~~
−
−	~~Digging around, it looked as if there were only three keys which ACPI~~
−	~~handled by default - the Power Off key, the Suspend key (Fn-F4) and the~~
−	~~Lid key. I found that I had to provide a handler for the Suspend key,~~
−	~~but for simplicity I left the other two alone, and most other special~~
−	~~purpose keys, eg. Fn-Home (LED brighter), Fn-End (LED dimmer), Fn-PgUp~~
−	~~(Screen light), kept on working anyway. Fn-F3 (Screen blank), didn't~~
−	~~work and nor (fortunately) did Fn-F12, Suspend to disk; Fn-F7, Switch to~~
−	~~video, seemed to - at least, it blanked the LCD. I then tried unloading~~
−	~~suspicious drivers such as USB, but could still only enter Suspend mode~~
−	~~and not recover; finally I built a kernel with no loadable modules~~
−	~~except networking, and the minimum of options - no USB, no PCMCIA,~~
−	~~nothing that wasn't actually present when the machine booted. That~~
−	~~finally worked, and I could suspend to disk with Fn-F4 and recover by~~
−	~~pressing Fn (but no other key - I seem to recall that any keypress would~~
−	~~work with the original BIOS).~~
−
−	~~When the machine is running, the Lid switch blanks the screen when~~
−	~~pressed and restores on release, but if the machine is suspended~~
−	~~pressing the switch does nothing and releasing it brings the machine out~~
−	~~of suspend mode. That seems reasonable. Commands echoed to eg:~~
−	~~/proc/acpi/ibm/light can be mixed with the appropriate keypresses (here,~~
−	~~Fn-PgUp) without problems.~~
−
−	~~I started re-enabling the various bits of hardware I needed one by one,~~
−	~~but when I re-enabled the Savage S3 framebuffer support the machine~~
−	~~would enter suspend, but would hang partway through re-emergence.~~
−
−	~~I then disabled the S3 stuff and enabled the Intel 830M framebuffer code~~
−	~~(I don't know how this relates to the S3 driver, but the T23 apparently~~
−	~~has both chips) and the suspend worked again. The S3 driver is handy in~~
−	~~text mode, since it gives more lines per screen (and a nice penguin logo~~
−	~~on boot-up) but the system still runs eg: X windows reasonably well.~~
−
−	~~Suspending and re-emerging with USB support and a USB memory key~~
−	~~plugged in, and with X windows running, then worked fine; at the~~
−	~~moment I don't have the hardware to test anything more. Some things~~
−	~~are still odd - the CPU (Pentium IIIM) has power management but not~~
−	~~throttling, and doesn't at the moment change speed automatically.~~
−	~~There must be a way around this, but since the CPU has only two speeds~~
−	~~it's easier to use a shell script to flip between the performance and~~
−	~~powersave kernel governors; everything needed can be found in the~~
−	~~/sys/devices/system/cpu/cpu0/cpufreq directory.~~
−
−	~~The Bay LED wrongly stays lit even when in suspend mode on battery~~
−	~~(unlike the Power LED), but the most recent (1.1) ibm_acpi module~~
−	~~provides an ACPI LED device which controls most of the LEDs (the Bay LED~~
−	~~is 4), and when my configuration has stabilised I'll set the LED up via~~
−	~~the suspend script. With the CPU on low speed (if it matters) and the~~
−	~~LED off the power consumption in Suspend mode is around 580mW.~~
−
−	~~I hope this helps someone else with their T23, because they are very~~
−	~~nice machines, and quite versatile; this one seems to be able to deal~~
−	~~with most forms of networking and mass storage pretty much out of the~~
−	~~box. It looks as if the software to control full ACPI functionality has~~
−	~~only stabilised within the last few months (ie: mid-2005), so if you~~
−	~~have problems, try upgrading to IBM's latest BIOS and EBIOS, and a~~
−	~~kernel >=2.12. With luck, the next version or so of the S3 driver will~~
−	~~be free of its hang problem.~~

← Older revision		Revision as of 02:07, 15 November 2005
Line 1:		Line 1:
	[[:Category:T23\|T23]][[Category:T23]]		[[:Category:T23\|T23]][[Category:T23]]
		+	== T23 and ACPI and Suspend to RAM ==
		+	I recently bought a second-hand Thinkpad T23, Model 2647-4MG, and
		+	decided to run Gentoo Linux 2.6.12-r6 on it; this is the 2005.1 release
		+	on a DVD, since I have limited internet access.
		+
		+	The default kernel booted OK, and recognised all the devices (tho' I
		+	haven't tested the modem, and I've run X-windows only briefly.)
		+	However, I wanted software suspend, and I couldn't get that to work at
		+	all.
		+
		+	The first complaint from dmesg was that ACPI wasn't enabled in the BIOS;
		+	the T23 BIOS has no mention of ACPI, so I added lapic to the kernel
		+	arguments and that went away. The next problem was a large number of
		+	ACPI error messages, generally of the form AE_NOT_EXIST, so I got the
		+	Intel iasl compiler source from their site and compiled it. It compiled
		+	cleanly, and de-compiling and re-compiling the DSDT gave one Error and
		+	one Remark. I fixed them as best I could, and loaded the new DSDT on
		+	boot with the kernel's "Custom DSDT" option; this worked correctly, but
		+	dmesg still showed a lot of ACPI error messages, including two which
		+	said "Found ECDT" and "Could not use ECDT".
		+
		+	Rather than mess with the ECDT straightaway, I decided to upgrade to the
		+	latest BIOS and Embedded Controller BIOS. The system came with (the
		+	original) versions 1.12 and 1.04, so I downloaded versions 1.18 and
		+	1.06a from the IBM Website. The installers come in floppy disk and
		+	Windows-based versions, and I used them under Windows 2000. Mercifully
		+	the re-flash worked as advertised, tho' interestingly the F12 "Select
		+	Boot Device" menu changed slightly, and at first it appeared to have
		+	lost the "Boot from USB" option, although that was enabled in the BIOS.
		+	Apparently the menu now simply calls a USB memory stick a hard drive.
		+	Anyway, boot from USB still works.
		+
		+	Booting into Linux then gave me no error messages, and dmesg showed that
		+	the ACPI had found the ECDT and enabled the interpreter. There was also
		+	a full set of ACPI entries under /proc. Although the DSDT had changed,
		+	de-compiling and re-compiling with iasl showed that the error that had
		+	originally bothered me was still there, so I let it be. I then loaded
		+	acpid, which handles the ACPI buttons through scripts in /etc/acpi.
		+	Tying Fn-f4 to "echo -n 3 >/proc/acpi/sleep" suspended the system, but
		+	nothing would bring it back. Fortunately the Power Off button was still
		+	functional.
		+
		+	Digging around, it looked as if there were only three keys which ACPI
		+	handled by default - the Power Off key, the Suspend key (Fn-F4) and the
		+	Lid key. I found that I had to provide a handler for the Suspend key,
		+	but for simplicity I left the other two alone, and most other special
		+	purpose keys, eg. Fn-Home (LED brighter), Fn-End (LED dimmer), Fn-PgUp
		+	(Screen light), kept on working anyway. Fn-F3 (Screen blank), didn't
		+	work and nor (fortunately) did Fn-F12, Suspend to disk; Fn-F7, Switch to
		+	video, seemed to - at least, it blanked the LCD. I then tried unloading
		+	suspicious drivers such as USB, but could still only enter Suspend mode
		+	and not recover; finally I built a kernel with no loadable modules
		+	except networking, and the minimum of options - no USB, no PCMCIA,
		+	nothing that wasn't actually present when the machine booted. That
		+	finally worked, and I could suspend to disk with Fn-F4 and recover by
		+	pressing Fn (but no other key - I seem to recall that any keypress would
		+	work with the original BIOS).
		+
		+	When the machine is running, the Lid switch blanks the screen when
		+	pressed and restores on release, but if the machine is suspended
		+	pressing the switch does nothing and releasing it brings the machine out
		+	of suspend mode. That seems reasonable. Commands echoed to eg:
		+	/proc/acpi/ibm/light can be mixed with the appropriate keypresses (here,
		+	Fn-PgUp) without problems.
		+
		+	I started re-enabling the various bits of hardware I needed one by one,
		+	but when I re-enabled the Savage S3 framebuffer support the machine
		+	would enter suspend, but would hang partway through re-emergence.
		+
		+	I then disabled the S3 stuff and enabled the Intel 830M framebuffer code
		+	(I don't know how this relates to the S3 driver, but the T23 apparently
		+	has both chips) and the suspend worked again. The S3 driver is handy in
		+	text mode, since it gives more lines per screen (and a nice penguin logo
		+	on boot-up) but the system still runs eg: X windows reasonably well.
		+
		+	Suspending and re-emerging with USB support and a USB memory key
		+	plugged in, and with X windows running, then worked fine; at the
		+	moment I don't have the hardware to test anything more. Some things
		+	are still odd - the CPU (Pentium IIIM) has power management but not
		+	throttling, and doesn't at the moment change speed automatically.
		+	There must be a way around this, but since the CPU has only two speeds
		+	it's easier to use a shell script to flip between the performance and
		+	powersave kernel governors; everything needed can be found in the
		+	/sys/devices/system/cpu/cpu0/cpufreq directory.
		+
		+	The Bay LED wrongly stays lit even when in suspend mode on battery
		+	(unlike the Power LED), but the most recent (1.1) ibm_acpi module
		+	provides an ACPI LED device which controls most of the LEDs (the Bay LED
		+	is 4), and when my configuration has stabilised I'll set the LED up via
		+	the suspend script. With the CPU on low speed (if it matters) and the
		+	LED off the power consumption in Suspend mode is around 580mW.
		+
		+	I hope this helps someone else with their T23, because they are very
		+	nice machines, and quite versatile; this one seems to be able to deal
		+	with most forms of networking and mass storage pretty much out of the
		+	box. It looks as if the software to control full ACPI functionality has
		+	only stabilised within the last few months (ie: mid-2005), so if you
		+	have problems, try upgrading to IBM's latest BIOS and EBIOS, and a
		+	kernel >=2.12. With luck, the next version or so of the S3 driver will
		+	be free of its hang problem.