Pali Rohár <pali@xxxxxxxxxx> writes: > On Friday 26 March 2021 18:51:42 Toke Høiland-Jørgensen wrote: >> Pali Rohár <pali@xxxxxxxxxx> writes: >> > On Friday 26 March 2021 17:54:38 Toke Høiland-Jørgensen wrote: >> >> So we have these >> >> cases: >> >> >> >> ASPM disabled: ath9k, ath10k and mt76 cards all work >> >> ASPM enabled, no patch: only mt76 card works >> >> ASPM enabled + patch: ath10k and mt76 cards work >> >> >> >> So IDK, maybe the ath9k card needs a quirk as well? Or the mvebu board >> >> is just generally flaky? >> > >> > I'm not sure. Maybe ASPM is somehow buggy on ath9k or needs some special >> > handling. But issue is not at PCI config space as ath9k driver start >> > initialization of this card. Needs also some debugging in ath9k driver >> > if it prints that strange "mac chip rev" error. >> >> Well that's just being output because it gets a revision that it doesn't >> recognise - which it seems to be just reading from a register: >> >> https://elixir.bootlin.com/linux/latest/source/drivers/net/wireless/ath/ath9k/hw.c#L255 >> >> The value returned is consistent with the value returned just being >> 0xffffffff. Which from looking at ioread32() is the value being returned >> on a failed read. So there's a driver bug there - the check against -EIO >> here is obviously nonsensical: >> >> https://elixir.bootlin.com/linux/latest/source/drivers/net/wireless/ath/ath9k/hw.c#L290 >> >> But the underlying cause appears to be that the read from the register >> fails, which I suppose is related to something the PCI bus does? >> >> > I think this issue should be handled separately. Could you report it >> > also to ath9k mailing list (and CC me)? Maybe other ath developers would >> > know some more details. >> >> I'll send a patch for the nonsensical check above, but other than that I >> think we're still in PCI land here, or? > > First, can you try to enable my quirk also for this ath9k card with ASPM > enabled? Yup, with this I get both devices working: diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index 8ff690c7679d..7e2f9c69f6b2 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -3583,6 +3583,7 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ATHEROS, 0x0034, quirk_no_bus_reset); * PCIe bridge has forced link speed to 2.5 GT/s via PCI_EXP_LNKCTL2 register. */ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ATHEROS, 0x003c, quirk_no_bus_reset_and_no_retrain_link); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ATHEROS, 0x002e, quirk_no_bus_reset_and_no_retrain_link); /* * Root port on some Cavium CN8xxx chips do not successfully complete a bus > > I have there another ath9k card which after toggling link retraining > changes PCI device ID (really!) to 0xABCD. But lspci ... > > There is long story about broken ath9k cards that are reporting 0xABCD > id on x86 machines with specific BIOS versions. It can be find in > ath9k-devel mailing list archive: > > https://www.mail-archive.com/ath9k-devel@xxxxxxxxxxxxxxx/msg07529.html > > Maybe we now found root cause of this ABCD? If yes, then it also answers > why above ath9k driver check fails (device id was changed) and also > because kernel see correct id (kernel reads id before configuring ASPM > and therefore before triggering link retraining). > >> >> > Can you send PCI device id of your ath9k card (lspci -nn)? Because all >> >> > my tested ath9k cards have different PCI device id. >> >> >> >> [root@omnia-arch ~]# lspci -nn >> >> 00:01.0 PCI bridge [0604]: Marvell Technology Group Ltd. Device [11ab:6820] (rev 04) >> >> 00:02.0 PCI bridge [0604]: Marvell Technology Group Ltd. Device [11ab:6820] (rev 04) >> >> 00:03.0 PCI bridge [0604]: Marvell Technology Group Ltd. Device [11ab:6820] (rev 04) >> >> 01:00.0 Network controller [0280]: Qualcomm Atheros AR9287 Wireless Network Adapter (PCI-Express) [168c:002e] (rev 01) >> >> 02:00.0 Network controller [0280]: Qualcomm Atheros QCA986x/988x 802.11ac Wireless Network Adapter [168c:003c] >> > >> > That is fine. Also all ath9k testing cards have id 0x002e. > > Today I found out that lspci -nn may lie! Please send output from > command: lspci -nn -x because real PCI device id can read only from -x > hexdump output. Without the quirk added to the ath9k: 01:00.0 Network controller [0280]: Qualcomm Atheros AR9287 Wireless Network Adapter (PCI-Express) [168c:002e] (rev 01) 00: 8c 16 2e 00 02 00 10 00 01 00 80 02 10 00 00 00 10: 04 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 20: 00 00 00 00 00 00 00 00 00 00 00 00 8c 16 a4 30 30: 00 00 00 00 40 00 00 00 00 00 00 00 3d 01 00 00 02:00.0 Network controller [0280]: Qualcomm Atheros QCA986x/988x 802.11ac Wireless Network Adapter [168c:003c] 00: 8c 16 3c 00 46 05 10 00 00 00 80 02 10 00 00 00 10: 04 00 20 e0 00 00 00 00 00 00 00 00 00 00 00 00 20: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 30: 00 00 20 ea 40 00 00 00 00 00 00 00 3e 01 00 00 And with: 01:00.0 Network controller [0280]: Qualcomm Atheros AR9287 Wireless Network Adapter (PCI-Express) [168c:002e] (rev 01) 00: 8c 16 2e 00 46 01 10 00 01 00 80 02 10 00 00 00 10: 04 00 00 e0 00 00 00 00 00 00 00 00 00 00 00 00 20: 00 00 00 00 00 00 00 00 00 00 00 00 8c 16 a4 30 30: 00 00 00 00 40 00 00 00 00 00 00 00 3d 01 00 00 02:00.0 Network controller [0280]: Qualcomm Atheros QCA986x/988x 802.11ac Wireless Network Adapter [168c:003c] 00: 8c 16 3c 00 46 05 10 00 00 00 80 02 10 00 00 00 10: 04 00 20 e0 00 00 00 00 00 00 00 00 00 00 00 00 20: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 30: 00 00 20 ea 40 00 00 00 00 00 00 00 3e 01 00 00 Is that change in bytes 5 and 6 significant? -Toke
