Switching ICH7 to ACPI mode?

Switching ICH7 to ACPI mode?

[Florian Echtler]

Hello Jeff,

my wife's ACER Aspire 5550 notebook has a ICH7 controller which is
eternally in "legacy" mode - the crippled BIOS is doesn't offer any
option to switch it to AHCI mode. It's basically running fine using the
ata_piix driver, but it never comes out of resume, only the hard disk
LED lights up and stays that way.

lspci -v:
00:1f.2 IDE interface: Intel Corporation 82801GBM/GHM (ICH7 Family) SATA
IDE Controller (rev 02) (prog-if 80 [Master])
	Subsystem: Acer Incorporated [ALI] Unknown device 0108
	Flags: bus master, 66MHz, medium devsel, latency 0, IRQ 19
	I/O ports at 01f0 [size=8]
	I/O ports at 03f4 [size=1]
	I/O ports at 0170 [size=8]
	I/O ports at 0374 [size=1]
	I/O ports at 18b0 [size=16]
	Capabilities: [70] Power Management version 2
	Kernel driver in use: ata_piix

lspci -n:
00:1f.2 0101: 8086:27c4 (rev 02)

I thought about switching the controller to AHCI mode to try suspend
with the ahci driver, and according to the Intel ICH7 spec, section
12.1.33, there's a single register (MAP) which controls the operating
mode of the chipset.

So, what I thought about is basically this:
- patch the ata_piix driver to switch the MAP register and un-claim the
device
- hope that the ahci driver then succeeds in operating the controller

A short disclaimer: I have done some kernel coding in the past, but I'm
definitely not an expert, so I may very well be completely mistaken
about this.

Therefore, cue the questions:
- Is this plan even remotely sensible? 
- If so, can you give me some pointers on how to achieve this?
- Any other hints? ;-)

Many thanks, 
Yours, Florian

P.S. Here's an excerpt from the kernel log (2.6.25):

oliver ata_piix 0000:00:1f.2: version 2.12
oliver ACPI: PCI Interrupt 0000:00:1f.2[B] -> GSI 19 (level, low) -> IRQ
19
oliver ata_piix 0000:00:1f.2: MAP [ IDE IDE P1 P3 ]
oliver PCI: Setting latency timer of device 0000:00:1f.2 to 64
oliver scsi0 : ata_piix
oliver scsi1 : ata_piix
oliver ata1: PATA max UDMA/100 cmd 0x1f0 ctl 0x3f6 bmdma 0x18b0 irq 14
oliver ata2: SATA max UDMA/133 cmd 0x170 ctl 0x376 bmdma 0x18b8 irq 15

-- 
0666 - Filemode of the Beast

Re: Switching ICH7 to ACPI mode?

[Andre Tomt]

Florian Echtler wrote:
> Hello Jeff,
> 
> my wife's ACER Aspire 5550 notebook has a ICH7 controller which is
> eternally in "legacy" mode - the crippled BIOS is doesn't offer any
> option to switch it to AHCI mode. It's basically running fine using the
> ata_piix driver, but it never comes out of resume, only the hard disk
> LED lights up and stays that way.

You could try Matthews patch to force-enable AHCI:
http://www.codon.org.uk/~mjg59/tmp/ahci_quirk_cleanup.diff

Note you might have to remove the #if 0 for some chips. See 
http://mjg59.livejournal.com/85504.html

Re: Switching ICH7 to AHCI mode?

[Florian Echtler]

> > my wife's ACER Aspire 5550 notebook has a ICH7 controller which is
> > eternally in "legacy" mode - the crippled BIOS is doesn't offer any
> > option to switch it to AHCI mode. It's basically running fine using the
> > ata_piix driver, but it never comes out of resume, only the hard disk
> > LED lights up and stays that way.
> You could try Matthews patch to force-enable AHCI:
> http://www.codon.org.uk/~mjg59/tmp/ahci_quirk_cleanup.diff
> Note you might have to remove the #if 0 for some chips. See 
> http://mjg59.livejournal.com/85504.html

Thanks, this does exactly what I was planning to do, and in a cleaner
fashion, too (I had forgotten about what quirks are for). I'll try the
patch later today and post the results.

Yours, Florian
-- 
0666 - Filemode of the Beast