On Wednesday 31 March 2021 16:02:42 Toke Høiland-Jørgensen wrote: > 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 Ok, thank you for testing! I'm seeing that testing unit 0x0030 (AR93xx) also needs this quirk, so I will mark all Atheros chips in above no bus reset list with no retrain link quirk. > > > > 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 > Yesterday both MJ and Bjorn told me to use lspci '-b' switch which instruct lspci to parse capabilities from config space (instead of kernel cache). Could you try to run 'lspci -nn -vv' and 'lspci -nn -vv -b' and compare results? If something changes? Anyway I have discussion with Adrian Chadd about 0xABCD issue and these Qualcomm/Atheros cards. When post-AR9300 card is not initialized it reports PCI device id 0xABCD. Pre-AR9300 cards should report correct PCI device id even when it is not initialized. WLE200 is AR9287-based, so it reports always correct id, should not change it during usage. But seems that also this AR9287 has issue with EEPROM/OTP as you figured out that ath9k driver is not able to read some device id from internal register. So please prepare patch for fixing -EIO in ath9k. PCI vendor & device id is in first 4 bytes and as you can see it is correct and was not changed. So I guess lspci output would not change for this card. > Is that change in bytes 5 and 6 significant? At offset 0x04 is 16bit PCI Command Register. In second (with) output is set bit 2 which means that Bus Mastering is enabled. This is normal and required when card communicate with system. Then is enabled bit 6 (Parity Error Response) and bit 8 (SERR# Enable), both for error reporting. This is normal when device is active. So nothing suspicious here. > -Toke >
