linux-kernel - Re: [PATCH 3/3] nvmem: qfprom: Don't touch certain fuses

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Message-ID: <14b62a74-4b4f-42b9-6043-ab8445a3f627@linaro.org>
Date:   Mon, 5 Oct 2020 10:12:32 +0100
From:   Srinivas Kandagatla <srinivas.kandagatla@...aro.org>
To:     Evan Green <evgreen@...omium.org>
Cc:     Rob Herring <robh+dt@...nel.org>,
        Bjorn Andersson <bjorn.andersson@...aro.org>,
        Douglas Anderson <dianders@...omium.org>,
        Stephen Boyd <swboyd@...omium.org>,
        LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 3/3] nvmem: qfprom: Don't touch certain fuses



On 01/10/2020 22:49, Evan Green wrote:
> Oh no, I realized this isn't nearly as beautiful when I try to move it
> into the core. The low level read/write interface between the nvmem
> core and the driver is a range. So to move this into the core I'd have
> to implement all the overlap computation logic to potentially break up
> a read into several small reads in cases where there are many little
> keepout ranges. It was much simpler when I could just check each byte
> offset individually, and because I was doing it in this one
> rarely-used driver I could make that performance tradeoff without much
> penalty.
> 
> I could do all range/overlap handling if you want, but it'll be a
> bigger change, and I worry my driver would be the only one to end up
> using it. What do you think?

I still think this should go in to core. core should be able to avoid 
checking by the presence of any restricted range, so it should not be a 
overhead for other non-users. regmap has similar feature we can take 
some inspiration from that code!!


--srini


> -Evan