-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 05/17/2013 08:40 PM, Bjorn Helgaas wrote: > Right; I meant RO per the PCIe spec. If it's RW on your chip, > setpci should be able to write it. I assume it would do no good to change it at this point; it would need to already be set at the time the kernel reads it and decides whether or not to enable it, so I'd have to have grub set it before loading the kernel. > If you can measure the power consumption, you might be able to see > a difference there. I've seen people report that, but don't know > how they do it. For example: > https://lkml.kernel.org/r/CANUX_P3F5YhbZX3WGU-j1AGpbXb_T9Bis2ErhvKkFMtDvzatVQ@xxxxxxxxxxxxxx After > enabling it on both ends ( despite the root port still claiming it is not supported ) I still see ~121 watts according to the Kill-A-Watt my system is plugged into. Oh well. Now that I double check myself, I realize that I misread the Intel spec. I was actually looking at the description for the link control register instead of capabilities. It uses the word "supported" instead of "enabled" when describing the enable bits in the control register, and they seem to skip right over describing the capability register. Trying to write to that has no effect, so it seems the CPU is really telling me it doesn't support ASPM on that link, though it is supposed to according to the feature description section of the data sheet. I am at a loss. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) Comment: Using GnuPG with undefined - http://www.enigmail.net/ iQEcBAEBAgAGBQJRltdlAAoJEJrBOlT6nu75O60IAJEEfQfoRgEP24/+5/SDIfnF lp5rBUc0afHcvV10m/5FAN8nefVfuLn0I6Iq2sHAgKPj7VG032MYXIAddrLK0tDH owFXqgsUTHemfsrTz+QCKQnJzZVu9iReyXRVovFF/j+jtRs9X45QD8tJHKSUKPMb uEyy7WeAoxxT6W6cIZSWrRChUnvq3soAcUiPkGdCHJep9jM8vBjidrADENavpzl6 tSHy/jEh5Cehr5oBX8JXB3e2x4AaDj5AE2CPWq1/ttQd0FRcUWZEHOZEcL2gN3Sp AGm5efe64Gdcl48yqP5WQuGM0K0dHXoXbRkWRNy4LOxP43gynUJWY4ulFqB06SM= =MOhM -----END PGP SIGNATURE----- -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
