lspci -nnk

02:00.0 Network controller [0280]: Qualcomm Atheros QCA9377 802.11ac Wireless Network Adapter [168c:0042] (rev 31)
Subsystem: Lite-On Communications Inc QCA9377 802.11ac Wireless Network Adapter [11ad:08a6]


$ dmesg | grep ath10k

[    5.148484] ath10k_pci 0000:02:00.0: pci irq msi oper_irq_mode 2 irq_mode 0 reset_mode 0
[    5.575049] ath10k_pci 0000:02:00.0: Direct firmware load for ath10k/pre-cal-pci-0000:02:00.0.bin failed with error -2
[    5.575081] ath10k_pci 0000:02:00.0: Direct firmware load for ath10k/cal-pci-0000:02:00.0.bin failed with error -2
[    5.579520] ath10k_pci 0000:02:00.0: qca9377 hw1.1 target 0x05020001 chip_id 0x003821ff sub 11ad:08a6
[    5.579525] ath10k_pci 0000:02:00.0: kconfig debug 1 debugfs 1 tracing 0 dfs 0 testmode 0
[    5.580801] ath10k_pci 0000:02:00.0: firmware ver WLAN.TF.2.1-00021-QCARMSWP-1 api 6 features wowlan,ignore-otp crc32 42e41877
[    8.650037] ath10k_pci 0000:02:00.0: unable to read from the device
[    8.650040] ath10k_pci 0000:02:00.0: could not execute otp for board id check: -110
[    8.650042] ath10k_pci 0000:02:00.0: failed to get board id from otp: -110
[    8.650068] ath10k_pci 0000:02:00.0: could not probe fw (-110)

Adapter works fine with firmware-5 (WLAN.TF.1.0-00002-QCATFSWPZ-5www)

But when both firmware-6 (WLAN.TF.2.1-00021-QCARMSWP-1) and firmware-5 are in the same directory it tries firmware-6 with the above results and no wifi.

So my temporary solution is to remove firmware-6 and notice txt file from directory but this isn't an optimal solution.