Re: [PATCH v2 1/2] dt-bindings: remoteproc: qcom: Add firmware bindings for Q6V5

From: Brian Norris
Date: Thu Jan 03 2019 - 18:51:53 EST


On Thu, Jan 03, 2019 at 03:30:14PM -0800, Brian Norris wrote:
> On Fri, Dec 28, 2018 at 10:18:18AM +0530, Sibi Sankar wrote:
> > +- firmware-name:
> > + Usage: optional
> > + Value type: <string>
> > + Definition: must list the relative firmware image path for the
> > + Hexagon Core.
>
> Relative to what? I still think it's a terrible idea that your driver
> looks for files at the top-level /lib/firmware/ directory, but now
> you're leaking this into the device tree. This should at a bare minimum
> be namespaced to something like the qcom/ sub-directory. But ideally,
> the driver would automatically be deriving a further sub-directory of
> qcom/ based on the chipset or something, and then the only thing you'd
> describe here is some kind of variant string -- something akin to
> ath10k's qcom,ath10k-calibration-variant (see
> Documentation/devicetree/bindings/net/wireless/qcom,ath10k.txt), which
> doesn't require a full path-name or any hierarchy.

Oh, I see Rob actually recommended this binding in v1, and it's (sort
of) in use by a few other drivers. Is it really expected that we put
arbitrary pathnames in device tree? None of the binding documentation
seems very specific to me, and their implementations *do* allow
arbitrary text. As it stands today, this is a great recipe for name
collision -- e.g., how the driver today suggests "modem.XYZ" names; is
Qualcomm really the only one out there making modems? :D

So my natural instinct is to avoid this. But if that's what everybody
wants...

Brian