From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Rutland Subject: Re: ath10k: calibration data through Device Tree? Date: Thu, 2 Oct 2014 14:29:15 +0100 Message-ID: <20141002132914.GN5788@leverpostej> References: <87tx3mmx4s.fsf@kamboji.qca.qualcomm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <87tx3mmx4s.fsf-HodKDYzPHsUD5k0oWYwrnHL1okKdlPRT@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Kalle Valo Cc: "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "ath10k-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" List-Id: devicetree@vger.kernel.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. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html