From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bjorn Andersson Subject: Re: [PATCH v2 1/2] dt-bindings: remoteproc: qcom: Add firmware bindings for Q6V5 Date: Thu, 3 Jan 2019 16:01:45 -0800 Message-ID: <20190104000145.GJ31596@builder> References: <20181228044819.5697-1-sibis@codeaurora.org> <20181228044819.5697-2-sibis@codeaurora.org> <20190103233014.GA181833@google.com> <20190103235043.GA195759@google.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20190103235043.GA195759@google.com> Sender: linux-kernel-owner@vger.kernel.org To: Brian Norris Cc: Sibi Sankar , david.brown@linaro.org, robh+dt@kernel.org, mark.rutland@arm.com, andy.gross@linaro.org, akdwived@codeaurora.org, clew@codeaurora.org, linux-kernel@vger.kernel.org, linux-arm-msm-owner@vger.kernel.org, ohad@wizery.com, linux-remoteproc@vger.kernel.org, devicetree@vger.kernel.org List-Id: devicetree@vger.kernel.org On Thu 03 Jan 15:50 PST 2019, Brian Norris wrote: > 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: > > > + 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... > I share your concern about this, but I came to suggest this as the driver cares about platforms but the firmware is (often?) device/product-specific. E.g. we will serve the MTP and Pixel 3 with the qcom,sdm845-adsp-pas compatible, but they are unlikely to run the same adsp firmware. This allows the individual dtb to specify which firmware the driver should use. Regards, Bjorn