Re: [PATCH 3/5] firmware: revamp firmware documentation

From: Luis R. Rodriguez
Date: Fri Dec 16 2016 - 04:19:02 EST


On Tue, Dec 13, 2016 at 02:30:22PM +0100, RafaÅ MiÅecki wrote:
> On 13 December 2016 at 14:26, Daniel Wagner <daniel.wagner@xxxxxxxxxxxx> wrote:
> >> +* Some firmware files may be really large in size. The remote-proc
> >> subsystem
> >> + is an example subsystem which deals with these sorts of firmware
> >> +* The firmware may need to be scraped out from some device specific
> >> location
> >> + dynamically, an example is calibration data for for some WiFi chipsets.
> >
> >
> > Maybe it is worth to mention, that the calibration data is unique to a given
> > chip, so it is individual. That is you would need to built for each device
> > you sell its own kernel.
>
> It's commonly unique to the device model, not a chip. The same chip
> can be used with different power amplifiers or different antennas.
> That's why you need model (board) specific calibration data.

>From what I recall in my 802.11 days this can be often very specific
per *batch* of cards not just chip/device model, so this depends on the
manufacturing process and date.

Luis