device: Turris Omnia WLan card: Compex wle900vx (Qualcomm Atheros AR9287 miniPCIe) ------ works with kernel 5.4.72 ath9k 0000:03:00.0: assign IRQ: got 52 ath9k 0000:03:00.0: enabling device (0140 -> 0142) ath9k 0000:03:00.0: enabling bus mastering ath: EEPROM regdomain: 0x0 ath: EEPROM indicates default country code should be used ath: doing EEPROM country->regdmn map search ath: country maps to regdmn code: 0x3a ath: Country alpha2 being used: US ath: Regpair used: 0x3a does not work with kernel 5.8.16 ath9k 0000:03:00.0: assign IRQ: got 52 ath9k 0000:03:00.0: enabling device (0000 -> 0002) ath9k 0000:03:00.0: enabling bus mastering ath: phy0: Mac Chip Rev 0xfffc0.f is not supported by this driver ath: phy0: Unable to initialize hardware; initialization status: -95 ath9k 0000:03:00.0: Failed to initialize device ath9k: probe of 0000:03:00.0 failed with error -95
Correction on the WLan-Card model, being the WLE200N2 from Compex (Qualcomm Atheros AR9287 miniPCIe) Otherwise, the regression appears being introduced with the 5.5 branch, run test 5.5.19 and the issue exhibits. Could not narrow it down to a particular ath9 commit since the kernel in those instance does not compile.
Not sure whether there is a potential correlation with bug 209833
closing as the correlation with bug 209833 confirmed, i.e. the issue with PCIEASPM