Pali Rohár <pali@xxxxxxxxxx> writes: > 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. SGTM. >> > >> > 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? Without -b there seems to be some [size=XX] suffixes to some lines, and there are some AtomicOpsCap lines that are not there with -b. Also, the IRQ number and memory offset for ath10k changed like this: - Interrupt: pin A routed to IRQ 63 - Region 0: Memory at e0200000 (64-bit, non-prefetchable) [size=2M] - Expansion ROM at e0400000 [disabled] [size=64K] + Interrupt: pin A routed to IRQ 62 + Region 0: Memory at e0200000 (64-bit, non-prefetchable) + Expansion ROM at ea200000 [disabled] > 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. Right, makes sense. > 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. Yup, already did, just forgot to Cc you (sorry about that): https://patchwork.kernel.org/project/linux-wireless/patch/20210326180819.142480-1-toke@xxxxxxxxxx/ > 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. Alright, cool. Thanks a lot for your help with this :) -Toke
