>>>> Anyway - I think I will just remove this pci_disable_link_state call >>>> and hopefully, it will stay long enough in linux-next so that people >>>> will report issues before it get into linux. >>>> I don't like leaving that code if it doesn't do anything. >>> >>> I think we broke at least some cases of pci_disable_link_state() a >>> while back. I'd like to fix it rather than just removing calls to it. >>> >>> Can someone collect a complete dmesg log and "lspci -vv" output? >>> >> >> I will. But I am on vacation right now and my linux box is not >> accessible right now... >> In any case, what you'll see is that ASPM is enabled (L1 enabled with >> or without driver). >> We are also seeing some really weird stuff (which I can't reproduce of >> course) like HW becoming not accessible, I guess it would be worth >> trying to *really* disable L1. I can tweak that in the code of the >> driver and tell the NIC that L1 is disabled. >> >> /* Disable L1-Active */ >> iwl_set_bits_prph(trans, APMG_PCIDEV_STT_REG, >> APMG_PCIDEV_STT_VAL_L1_ACT_DIS); >> >> Do you have an idea about *when* did pci_disable_link_state() break? > > No, not yet. After we figure out exactly what the problem is, we > should be able to determine when it broke. > > If I understand correctly, you have CONFIG_PCIEASPM=y, the iwlwifi > driver uses pci_disable_link_state() to disable L1, but the link state > stays in L0 all the time. So I think we should look at the dmesg log, > "lspci -vv" output before loading iwlwifi, and "lspci -vv" output > after loading iwlwifi. > I attached all the data you needed. The link state seems to go to L1 based on the low power the NIC consumes. So it seems that even if we use pci_disable_link_state() to disabled L1, L1 is still disabled. I can't really tweak the driver to clear the bit in the LnkCtl of the ConfigSpace, but I can tell the HW not to accept to go to L1 (since it is handshake based with the root complex IIRC). I can also use setpci, but then....
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dmesg
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