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From: Mark Rutland <mark.rutland-5wv7dgnIgG8@public.gmane.org>
To: Kalle Valo <kvalo-A+ZNKFmMK5xy9aJCnZT0Uw@public.gmane.org>
Cc: "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org"
	<devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>,
	"ath10k-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org"
	<ath10k-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org>
Subject: Re: ath10k: calibration data through Device Tree?
Date: Thu, 2 Oct 2014 14:29:15 +0100	[thread overview]
Message-ID: <20141002132914.GN5788@leverpostej> (raw)
In-Reply-To: <87tx3mmx4s.fsf-HodKDYzPHsUD5k0oWYwrnHL1okKdlPRT@public.gmane.org>

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.
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  parent reply	other threads:[~2014-10-02 13:29 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-10-02 13:14 ath10k: calibration data through Device Tree? Kalle Valo
     [not found] ` <87tx3mmx4s.fsf-HodKDYzPHsUD5k0oWYwrnHL1okKdlPRT@public.gmane.org>
2014-10-02 13:27   ` Arnd Bergmann
2014-10-02 13:47     ` Kalle Valo
     [not found]       ` <87lhoymvln.fsf-HodKDYzPHsUD5k0oWYwrnHL1okKdlPRT@public.gmane.org>
2014-10-02 14:19         ` Arnd Bergmann
2014-10-02 14:55           ` Kalle Valo
     [not found]             ` <87d2aamsg2.fsf-HodKDYzPHsUD5k0oWYwrnHL1okKdlPRT@public.gmane.org>
2014-10-02 15:58               ` Arnd Bergmann
2014-10-02 13:29   ` Mark Rutland [this message]
2014-10-02 13:44     ` Kalle Valo
     [not found]       ` <87ppeamvr9.fsf-HodKDYzPHsUD5k0oWYwrnHL1okKdlPRT@public.gmane.org>
2014-10-02 15:07         ` Mark Rutland
2014-10-02 19:05         ` Andy Lutomirski
     [not found]           ` <542DA1F7.9090904-kltTT9wpgjJwATOyAt5JVQ@public.gmane.org>
2014-10-02 19:28             ` Adrian Chadd
     [not found]               ` <CAJ-VmomR+AzsUVqSik=ejntHHhQf_wj9kU==uCqWyk27M7Gp9w-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2014-10-02 19:35                 ` Andy Lutomirski
     [not found]                   ` <CALCETrV_LoCJ_DHcyQ2ztyXfdH2vAF0r7OX29_nPj6gMcodBig-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2014-10-07 16:44                     ` Kalle Valo
     [not found]                       ` <87vbnvhls4.fsf-HodKDYzPHsUD5k0oWYwrnHL1okKdlPRT@public.gmane.org>
2014-10-17 12:25                         ` Kumar Gala
     [not found]                           ` <F0D1326B-4716-4897-8259-1591B64EB55C-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org>
2014-10-22 12:02                             ` Kalle Valo
2014-10-03 15:29             ` Arnd Bergmann
2014-10-03 16:24               ` Andy Lutomirski
2014-10-03 16:25               ` Mark Rutland
2014-10-03 16:42                 ` Arnd Bergmann
2014-10-03 16:54                   ` Andy Lutomirski
     [not found]                     ` <CALCETrWC9fXckgUGYWA8AcHT5SoxQc-EouV0U-sFr7v6279oow-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2014-10-03 17:21                       ` Adrian Chadd

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