-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 05/17/2013 05:28 PM, Bjorn Helgaas wrote:> A link has two ends. Both ends have to support ASPM in order for it > to work. But ASPM on a particular link has no dependency on > things elsewhere in the hierarchy. Got you... I guess I was still thinking regular PCI and the naming "root complex" made me think it was the whole root bridge, when it really is that particular x16 pcie port that goes to the radeon. > The link between 00:01.0 and 01:00.0 apparently only supports ASPM > on one end (the downstream end), so ASPM won't work on it. I'll check the Intel spec sheet again, but I'm pretty sure it really does support ASPM. The CPU probably allows writes to the register, and my bios must have configured it to say it doesn't support aspm. I guess I just need to wrangle setpci into trying to enable it despite it not advertising support, or maybe see if I can get grub to poke the capability register to make it say it supports it. One question I have though is how to identify which port device corresponds to which downstream device connected to it. In other words, how do you know 00:01.0 links to 01:00.0 ( other than seeing that it's the x16 and knowing the radeon is plugged into the x16 slot ). -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) Comment: Using GnuPG with undefined - http://www.enigmail.net/ iQEcBAEBAgAGBQJRlr8VAAoJEJrBOlT6nu75zL8IAImEt+ql6u1pqDSFPuDlLwSE fbFWYYxZAzEGnzbAKGMUhueKHAa4rEnH2ztM8CYxdj3GVfSoTpwgcvz21L/fq/6L z4OtChaw2cDiCevi95BR2xry2qBLnrHNq1qbD1yb832b5njCSr5SnTvUBUiH/4pN twEAJ3HZp7Vblts4UMmn5sOT3cGd1Yr6sJp4Y068vPSGyx5Ixm5ROYEedN5tBnBl zkeC+2vYXk0nIbMgJLWt4ZJRxXmX3/DXt8F1VL12NzlHpotuS5rPRpTR/el3sSty J6HH/jlgSm+L3zuSPTicVAQBvYGcRhi/NbKDFPnZGGB8E7HsE9SIwNxzjzImyV0= =X54u -----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
