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Author Topic: ASPM enabled logic changed  (Read 3635 times)

Offline nick65go

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ASPM enabled logic changed
« on: September 21, 2014, 05:17:00 AM »
To automaticaly enable ASPM (Active State Power Management) you need a good BIOS.
My BIOS is bad. Some users could tame it by using a kernel parameter in the boot-loader config line like
acpi_osi="Windows 2006" (the correct string is in assembled DSDT, a ACPI table);
to change the feature that the BIOS exposes to the kernel.

If BIOS is stuborn still, you need to force the ASMP manually using a kernel parameter in the boot-loader config line like pcie_aspm=force

But unfortunate the kernel guys changed the logic of activating ASPM.
1. You still need the pcie_aspm=force, but it just enables (not activate!) it.
2. you activate ASPM yourself, by issuing in a shell:
sudo sh -c "echo powersave > /sys/module/pcie_aspm/parameters/policy"

from my $ dmesg, without issuing the shell command:
Kernel command line: initrd=/boot/rootfs64a.gz,/boot/modules64a.gz tce=sda3 pcie_aspm=force BOOT_IMAGE=/boot/vmlinuz64
PCIe ASPM is forcibly enabled
pci0000:00: ACPI _OSC support notification failed, disabling PCIe ASPM

for me, the poke value in /sys activated ASMP and helped me at least to sleep longer my crazy GPU fan.
« Last Edit: September 21, 2014, 05:21:00 AM by nick65go »