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Date:   Tue, 19 Jun 2018 14:51:22 +0530
From:   Viresh Kumar <viresh.kumar@linaro.org>
To:     Taniya Das <tdas@codeaurora.org>
Cc:     Sudeep Holla <sudeep.holla@arm.com>,
        Amit Kucheria <amit.kucheria@verdurent.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Linux PM list <linux-pm@vger.kernel.org>,
        "Rafael J. Wysocki" <rjw@rjwysocki.net>,
        Stephen Boyd <sboyd@kernel.org>,
        Rajendra Nayak <rnayak@codeaurora.org>,
        "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
        <devicetree@vger.kernel.org>, Rob Herring <robh@kernel.org>,
        Saravana Kannan <skannan@codeaurora.org>
Subject: Re: [PATCH v4 1/2] dt-bindings: cpufreq: Introduce QCOM CPUFREQ FW
 bindings
Message-ID: <20180619092122.ul56qnh5uangti3e@vireshk-i7>
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On 19-06-18, 13:23, Taniya Das wrote:
> Driver code (The below representation is just for example).
> =============
> 
> V1
> #define ENABLE	0x0
> #define LUT_V1	0x110
> #define PERF_V1	0x920
> 
> V2
> #define LUT_V2	0x150
> #define PERF_V2	0x980
> 
> V3
> #define LUT_V3	0x120
> ....
> 
> Do you want me to use "compatible" flag to
> 
> if (compatible == v1)
>  enable =  readl_relaxed(X + LUT_V1);
> else if (compatible == v2)
>  enable = readl_relaxed(X + LUT_V2);
> else if (compatible == v3)
>  enable = readl_relaxed(X + LUT_V2);

You can have fields in a struct somewhere like enable_offset, which you can fill
based on compatible string only once during probe and then the rest of the code
would just do:

enable = readl_relaxed(X + struct->enable_offset);

-- 
viresh