A few days ago I talked about how noisy my new Dell Studio 15 was but I can now report back with the beginnings of a solution to that problem, and it doesn't appear to be ACPI related.

The first clue I needed was that if I switch to the proprietary fglrx drivers for the Radeon the fan quite quickly drops off to a much more reasonable level. It seems the fglrx drivers have issues, however, in particular I get big black patches on my screen. This video corruption happens especially in Firefox, but sometimes in other applications as well. They also appear to screw up my suspend/resume, which is probably even more annoying to me.

The second clue that I needed was that Radeon power management support has only just made it into recent kernels. Thanks to Michael Kirkland for providing me with both of those clues :-)

Looking under /sys/class/drm/ I find a whole bunch of stuff, but in particular there are /sys/class/drm/card0/device/power_method and /sys/class/drm/card0/device/power_profile.

Looking through the kernel source code I can see that power_profile can be set to low, mid, high, auto and default, while power_method can be set to either dynpm or profile.

Trying out all of these values, it seems I get the quietest result with the profile method and either the low or mid profile. The dynpm method is nearly as good, and I would think it should really be the default for a 'Mobility' chipset. From the detailed benchmarking that Phoronix did I wonder if it shouldn't be the default for everyone.

For myself, I see some small 'tearing' artifacts occasionally when running with the low profile. These disappear when I run with the mid profile, and since that seems to have pretty much the same temperature (and noise) results I'll go with that one. Though the laptop often does still make more noise than I would prefer it to, it is no longer annoying everyone in the room.

Not unexpectedly this seems to have a huge impact on power use, too. It appears that the laptop should now give me around 4.5 hours when I do everything I can think of to lower the power use, whereas before it was more like 2.5 hours.

Now I guess I can get back to hacking on DAViCal...

Really, I should have known better than to buy myself a rather 'bleeding-edge' laptop. I suppose I've been lucky with my last couple of laptops and was thinking that pretty much everything works on Linux. Or maybe I'm being picky, because in fact pretty much everything does work on my new Dell Studio.

I bought this laptop mainly because it has a 1920x1080 screen, without being a 17" monster. I had such a monster about four laptops ago (an enormous Sony Vaio weighing in at around 5kg and with a 1hr battery life) and it was an disaster: lots of weird proprietary stuff that never worked, like the external speakers in the docking station. But I loved that screen right up until the day Fraser threw a pair of scissors into it.

With the advent of mass-market 1920x1080 screens I've been waiting for them to arrive in laptops at a reasonable price, and the availability of this screen in a few possible laptops seemed to me to be that point.

It's a Dell Studio 15, and as well as the nice screen, it comes with a new Intel i7 Quad Core CPU, 6G RAM, 640G hard drive and a Blu-ray drive. While there are a few similar models around this one seemed to have the best mix of features-for-weight-and-price, so I bought my first Dell.

I built a USB key with the latest Debian Installer from Squeeze and installed that and everything came up pretty well. I had to use the broadcom-sta driver for the wireless, since the BCM 43224 is not (yet) supported by the free b43 driver (though from looking the mailing list people seem to be working on it, and it looks like it might not be too far away).

Everything seemed good. X came up on the (georgeous) screen. I don't care too much about 3D performance, but it was nice to note that the ATI 5000 series is expected to have full support as soon as it's integrated into the right places - it seems the code is written, and public, it just isn't incorporated into the 'radeon' driver quite yet. The fact that ATI is nowadays a free-software friendly company was one of the reasons for choosing this, in preference to an NVidia-based laptop.

But it seems that it isn't all roses. The fan in the laptop seems permanently on, and not on, in a quiet-just-barely-audible way, but ON, in an 'IN UR LAPTOPZ KOOLIN UR P0RCESSAZ' kind of a way. Too damn noisy for me to concentrate in a quiet room.

I've investigated what's going on, and it seems likely there are some ACPI misunderstandings happening. Some googling and some pecking around in /sys makes me wonder if the laptop expects some kind of configuration choice between favouring Active cooling and Passive cooling, and it's defaulted to the first one. Perhaps you get better benchmarks that way.

Linux ACPI also seems to only half understand it, it has two thermal zones, and one of them always appears with 0 temperature. I can see set points for the fans, but have no control over them. In particular this got me out reading the ACPI 4.0 specification, and it explicitly mentions this choice of favouring 'Active' vs 'Passive' as being done by configuring the passive trip point setting to a higher value than the low & high active trip points.

In the ACPI 4 spec (page 409) it says:

To implement a preference towards performance or energy conservation,
OSPM can request that the platform change the priority of active cooling
(performance) versus passive cooling (energy conservation/silence) by evaluating
the _SCP (Set Cooling Policy) object for the thermal zone or a corresponding
OS-specific interface to individual devices within a thermal zone.

This laptop is showing 'passive' at 95000 millidegrees celsius, and 'active' at 55000 / 75000 so right in line with the suggestion.

However I don't see any way in Linux to change these trip point values, and in any case I'm not convinced the laptop is actually obeying them at all. It should be that if I do nothing on the laptop for a while the temperature would surely drop below 55 degrees celsius. Surely a modern laptop will sit at under 40 degrees when it's quiescent, and the temperature sensor that does show me something sits at around 30 degrees in this too, 26.8, to be overprecise. That one doesn't budge either.

Looking in /sys/ I can't for the life of me find a way to set that cooling policy, and when I disassemble the DSDT it looks like a noop...

Thinking that perhaps there was a newer BIOS, I looked at the Dell site and found there was one. Great! Investigating even further, it seems Dell hardware has some interesting capability via libsmbios and some utilities which will let me install my BIOS from a Linux system... even better!

Linux is a second-class citizen though, and when I look for the Dell BIOS Hdr file I need there is no version of the file for this laptop - let alone the current BIOS version. And when I download the BIOS from Dell's website and unzip the first layer of packaging I find that both of the files inside will only run on Windows.

I added a FreeDOS boot stanza to Grub 2 in order to discover this, also discovering in the process that this is not well explained, and I could not find how to do it on the FreeDOS or Grub2 websites, so in passing, here is what I added into /etc/grub/40_custom :

menuentry 'BIOS Flash 1558 A09' --class os {
        set root='(hd0,msdos1)'
        linux16 /boot/memdisk
        initrd16  /boot/1558_A09.img
}

Which certainly does boot FreeDOS from Grub2, into the image built from the 8M FreeDOS base image, and which I called '1558_A09.img' because that seems to be one of Dell's reference numbers for this model / BIOS version.

So still no BIOS update for Andrew, it seems, and the laptop is probably going to continue to be noisy for some time. Possibly forever.

Suspend/Resume works though. Kernel mode-setting for the ATI Radeon Mobility HD 5450 (or whatever it is) seems to work. Building kernels seems to work. The Blu-ray drive seems to work, at least as far as reading CDs - just because I got a laptop with a "Full HD" screen doesn't mean I watch movies on it: those pixels are for programming on! In any case, after reading the literature of pain about playing Blu-ray disks on Linux I'm convinced that we won't be shelling out to buy one any any time soon.

After a bit more frustration I did manage to get the BIOS installed, using the hack I found here of running the Windows BIOS update under Wine and copying the BIOS file out of the temp directory while the error message is displayed. I could then download a random DOS-installable Phoenix BIOS to get copy of phlash16.exe and put those two files on the FreeDOS image I created earlier. Finally I was able to put that learning about how to boot FreeDOS from Grub2 to good use!

Unfortunately, having jumped through all of those hoops (including the frustration of trying to build and use Dell's firmware-extract tools on a Debian system), the fan continues to grind away at annoying volume, with no way that I have been able to find to control it, and the temperature sensors also seem wrong, since one doesn't budge from 0 and the other doesn't budge from 26800.

During boot I get a bunch of error messages, like:

[    1.049936] \_SB_.PCI0:_OSC invalid UUID

[    1.052202] pci 0000:00:1c.0: PME# supported from D0 D3hot D3cold
[    1.052210] pci 0000:00:1c.0: PME# disabled

[    1.065228] pci 0000:07:00.2: PME# supported from D0 D1 D2 D3hot D3cold
[    1.065237] pci 0000:07:00.2: PME# disabled

[    1.079086] Unable to assume PCIe control: Disabling ASPM

[    1.086412] HEST: Table is not found!

[    1.249906] ACPI: Fan [FAN0] (off)
[    1.249959] ACPI: Fan [FAN1] (off)

[    1.250093] [Firmware Bug]: ACPI: ACPI brightness control misses _BQC function

[    1.259118] acpi device:02: registered as cooling_device2
[    1.262132] thermal LNXTHERM:01: registered as thermal_zone0
[    1.262139] ACPI: Thermal Zone [TZ00] (27 C)
[    1.262561] thermal LNXTHERM:02: registered as thermal_zone1
[    1.262571] ACPI: Thermal Zone [TZ01] (0 C)

[    1.262598] ERST: Table is not found!

[    2.769664] i801_smbus 0000:00:1f.3: PCI INT C -> GSI 18 (level, low) -> IRQ 18
[    2.769670] ACPI: resource 0000:00:1f.3 [io  0x1840-0x185f] conflicts with ACPI
                         region SMBI [bus 1840-184f pref window disabled]
[    2.769672] ACPI: If an ACPI driver is available for this device, you should use it
                         instead of the native driver

I don't yet know what this all means, so I guess I'll be signing up for the linux-acpi mailing list to see if there's anything I can do to get things working better. Any pointers will be gratefully received :-)

Right about now I wonder if maybe I should have gone for the HP or the Asus, even if they were a little heavier and a bit more expensive and next time I get a new laptop I must remember not to spend more than $900 (USD$600) on it.

[Updated: 2010-09-08... Noise Problems Solved

For several years I've wanted to join the Calendaring and Scheduling Consortium and go to one of their events to get a chance to meet face-to-face with some of the luminaries in the calendaring world, but every time there is an event it seems to conflict with either linux.conf.au or my brother's wedding or something. Finally I've decided I can make the next meeting, so I've paid over the money to join the organisation and I'm travelling to the US next month for 'CalConnect XVI'. With that on my mind when I saw an HP 110 mini netbook on sale for NZD$588 from Harvey Normans I finally flipped over the 'shall I get one' threshold, hoping it will make a good 'travel laptop' for the upcoming trip.

After a few years of only buying laptops with Intel hardware, today I bought something totally different. It's not really what I wanted (which was an HP HDX 16t) but I get the feeling that none of these 16" HD 1080 laptops will make it to New Zealand for a while yet, and the NZ dollar has done such a nosedive recently that it's better not to wait any longer.

In the places that hold stock there seem to be some good specials around at the moment, and as the owner of a new free, open-source consulting business (i.e: a cheap bastard) I went shopping for the cheapest dual-core I could find with a half-decent screen, and I found the Asus X53K for $999 (USD$589) at Dick Smith, including a 2G ram upgrade to take it to 3G. It's entirely non-intel, with a 2GHz Turion dual-core, ATI Radeon X2300 with 1440x900 panel, Atheros AR2425 wifi and 160G HD. I'd bought a replacement 320G hard drive even before I got the laptop, so now I have a pristine, unbooted 160G hard drive with the install files for some other OS on it - no doubt I'll find a use for the disk, at least!

Since AMD got ATI to release all their chip documentation earlier this year I felt able to shell out for this, rather than the extra $100 for the model next to it, and it was nice too to get home and find that Atheros have recently released the HAL for their a/b/g chips. Which presumably means that they haven't done so for their 'n' chipsets, and I should continue to steer clear of that technology for a while yet...

I'm running Debian GNU/Linux 'Sid' on the Asus X53K and, everything pretty much just works out of the box. My installation process was to rsync the old laptop onto a new disk, and boot the new laptop from that - after compiling a new kernel more appropriate to the changed hardware.

After overcoming my own stupidity in not syncing the /dev/ underneath udev, which I easily googled my way out of, the only problem I've found so far is that the free radeon driver doesn't do 3d for me. Presumably the non-free ones would, but they won't compile against my 2.6.27 kernel so I don't know for sure. Fortunately I don't use 3d for anything so it's not a huge inconvenience to me. With 3G RAM and a fast 320G hard drive the laptop actually is an upgrade for me, too, and it has a webcam too, which I expect I'll look at in much the same way as I did the fingerprint reader on the old laptop. It will be good to finally hand that old one back to Catalyst, too, who have given me the flexibility to take my time on this.

Now to try and peel off all these stickers without damaging anything!