https://bugzilla.kernel.org/show_bug.cgi?id=218198 --- Comment #7 from Dieter Mummenschanz (dmummenschanz@xxxxxx) --- (In reply to Niklas.Cassel from comment #6) Hello Niklas, thanks for looking into this. > It would be nice if you could test with latest v6.7-rcX. Okay I took the latest 6.7-rc3 from Linux's git and included your patch. Booted up my Laptop, put it back to sleep and brought it up again. See attached log. I've disabed my link_power_management_policy override so all the time my system was stuck at pc2 package state according to powertop. > For devsleep to get enabled, you need "sadm sds" in the SATA controller Yep I can see that: [ 0.379531] ahci 0000:00:17.0: flags: 64bit ncq sntf stag pm clo only pio slum part ems sxs deso sadm sds apst > and "Dev-Sleep" in the SATA device print. I guess this is it? [ 1.031169] ata5.00: Features: Trust Dev-Sleep NCQ-sndrcv > Additionally, your lpm-policy (lpm-pol) has to be either ATA_LPM_MIN_POWER or > ATA_LPM_MIN_POWER_WITH_PARTIAL (i.e. lpm-pol has to print either 4 or 5). I'm afraid this is not the case here: [ 0.399005] ata1: SATA max UDMA/133 abar m2048@0x42233000 port 0x42233100 irq 125 lpm-pol 0 > Note that even if you have LPM_POLICY=3 (ATA_LPM_MED_POWER_WITH_DIPM) in your > Kconfig, ahci_update_initial_lpm_policy() will possibly override this by > default That would explain why I'm seeing "max_performance" in link_power_management_policy without overriding it. > The reason why many platforms do this override, is because: > "One of the requirement for modern x86 system to enter lowest power mode > (SLP_S0) is SATA IP block to be off. This is true even during when > platform is suspended to idle and not only in opportunistic (runtime) > suspend." > > "SATA IP block doesn't get turned off till SATA is in DEVSLP mode. Here > user has to either use scsi-host sysfs or tools like powertop to set > the sata-host link_power_management_policy to min_power." > > See: > https://github.com/torvalds/linux/commit/ > b1a9585cc396cac5a9e5a09b2721f3b8568e62d0 Thanks for the insight. > I would really not recommend you doing this, because when you force set > lpm policy via sysfs, ahci_update_initial_lpm_policy() is not called, > so if your platform requires ATA_LPM_MIN_* to enter lower power states, > you forcing lpm-policy to ATA_LPM_MED_POWER_WITH_DIPM will ensure that > you never enter lower power states. I understand however I do not know of any other way to enable lower package states on my machine. > So it appears that your port does not support devsleep... Anything we can do to preserve the old bwhaviour until 6.6? > PxDEVSLP.DSP (in AHCI specification) is the bit that determines if devsleep > is supported for a specific port. This bit is initialized by BIOS. > > So this could be a BIOS bug... > But you said that it works if you revert Damien's patch... Yes, I had no issues up to 6.7-rc1. > Perhaps you could test this patch: Yweah, see logs. > You mentioned that it works when you revert Damien's patch. > It could be interesting to see these prints, before/after the > suspend/resume both with and without the revert. I've attached the dmesg logs from kernel 6.6. Thanks again for your help Dieter -- You may reply to this email to add a comment. You are receiving this mail because: You are watching the assignee of the bug.
