[FS#928] Unable to turn on Archer C7 v2 5GHz wireless

[LEDE Bugs]

The following task has a new comment added:

FS#928 - Unable to turn on Archer C7 v2 5GHz wireless
User who did this - Victor Urvantsev (dimberr)

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looks like the driver looking for firmware "firmware-6.bin" and board file "board-2.bin" in /lib/firmware/ath10k/QCA988X/hw2.0/ 


In that directory there is only "firmware-5.bin" and board file "board.bin", so changing the name of this files helps to interface up and wlan0 starts working. 

however I get that output: 

[   10.147763] PCI: Enabling device 0000:00:00.0 (0000 -> 0002)
[   10.153813] ath10k_pci 0000:00:00.0: pci irq legacy oper_irq_mode 1 irq_mode 0 reset_mode 0
[   10.432679] ath10k_pci 0000:00:00.0: Direct firmware load for ath10k/pre-cal-pci-0000:00:00.0.bin failed with error -2
[   10.443768] ath10k_pci 0000:00:00.0: Falling back to user helper
[   10.559510] firmware ath10k!pre-cal-pci-0000:00:00.0.bin: firmware_loading_store: map pages failed
[   10.980782] ath10k_pci 0000:00:00.0: qca988x hw2.0 target 0x4100016c chip_id 0x043202ff sub 0000:0000
[   10.990352] ath10k_pci 0000:00:00.0: kconfig debug 0 debugfs 1 tracing 0 dfs 1 testmode 1
[   11.003370] ath10k_pci 0000:00:00.0: firmware ver 10.2.4-1.0-00037 api 6 features no-p2p,raw-mode,mfp,allows-mesh-bcast crc32 a4a  52adb
[   11.050887] ath10k_pci 0000:00:00.0: found invalid board magic
[   11.075449] ath10k_pci 0000:00:00.0: board_file api 1 bmi_id N/A crc32 bebc7c08
[   12.269255] ath10k_pci 0000:00:00.0: htt-ver 2.1 wmi-op 5 htt-op 2 cal file max-sta 128 raw 0 hwcrypto 1
[   12.409368] ath: EEPROM regdomain: 0x0

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More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=928#comment4290