Re: Aw: Re: Re: [PATCH 0/2] Power management fixes

[Damien Le Moal <dlemoal@kernel.org>]

On 1/31/24 20:49, Niklas Cassel wrote:
> On Wed, Jan 31, 2024 at 04:38:28PM +0900, Damien Le Moal wrote:
>> On 1/31/24 16:29, Dieter Mummenschanz wrote:
>>> Damien,
>>> so I've applied the patch to 6.8-rc2. Interesting thing is that the behaviour is 
>>> exactly the same as before (w/o the patch). Besides not 
>>> honoring CONFIG_SATA_MOBILE_LPM_POLICY=3 after boot my system refuses to 
>>> transition into lower power states > pc2 after resume even after letting it sit 
>>> idle for 10 minutes. Transition is only reached after issuing hdparm -Y. So if 
>>> the patch restores the original behaviour then why did it stop working?!
> 
> Hello Dieter,
> 
> Just to confirm,
> while testing Damien's patch on top of 6.8-rc2,
> did you still do:
> 
> for foo in /sys/class/scsi_host/host*/link_power_management_policy;
>   do echo med_power_with_dipm > $foo;
> done
> 
> It should be needed until we add (or modify the existing entry, if any)
> your PCI vendor and device id to use "board_ahci_low_power" instead of
> "board_ahci", see e.g.
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/drivers/ata/ahci.c?id=b8b8b4e0c052b2c06e1c4820a8001f4e0f77900f

Indeed. What is the AHCI adapter here ?
It would be interesting if it is a Tiger Lake :)

-- 
Damien Le Moal
Western Digital Research