ath10k: calibration data through Device Tree?

[Mark Rutland]

Hi,

> ath10k is a wireless driver for Qualcomm Atheros 802.11ac hardware and
> located in drivers/net/wireless/ath/ath10k/. Currently it only supports
> PCI devices.
> 
> Some of the devices store the calibration data to the host flash and the
> bootloader reads the data from the flash. And now we need a method to
> deliver the calibration data from bootloader to ath10k. 

What does this calibration data consist of?

What happens if you don't have the calibration data? Is it a critical
requirement for the use of the device, or does its absence simply result
in degraded performance?

What do you do on non-DT systems? Where does the information come from
in that case?

I'm somewhat puzzled as to why a discoverable PCI device would require
non-discoverable information to use.

> * The calibration data is now 2116 bytes, in the future it might be
>   longer. The data is unique for each radio and is created at the
>   factory.

Why would this change in future? Who is in charge of providing this
information, and deciding upon the format thereof?

> * ath10k must be able to reliably map the PCI device (=radio) to the
>   correct calibration data. Maybe with using PCI bus and slot numbers?

I guess we'd have to do something along those lines.

I'd like to get a better understanding of the problem before we start
figuring out how to pass an arbitrary blob of information around.

Thanks,
Mark.