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Date:   Fri, 24 Jul 2020 14:10:59 +0100
From:   Sudeep Holla <sudeep.holla@arm.com>
To:     Kefeng Wang <wangkefeng.wang@huawei.com>
Cc:     Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>,
        Mikko Perttunen <mperttunen@nvidia.com>,
        Sumit Gupta <sumitg@nvidia.com>,
        Viresh Kumar <viresh.kumar@linaro.org>,
        Sudeep Holla <sudeep.holla@arm.com>,
        Hulk Robot <hulkci@huawei.com>,
        "linux-kernel@vger.kernel.org List" <linux-kernel@vger.kernel.org>,
        linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH -next] arm64: Export __cpu_logical_map
Message-ID: <20200724131059.GB6521@bogus>
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 <82f750c4-d423-1ed8-a158-e75153745e07@huawei.com>
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On Fri, Jul 24, 2020 at 11:08:03AM +0800, Kefeng Wang wrote:
> +maillist
> 
> On 2020/7/24 11:04, Kefeng Wang wrote:
> > ERROR: modpost: "__cpu_logical_map" [drivers/cpufreq/tegra194-cpufreq.ko] undefined!
> > 
> > ARM64 tegra194-cpufreq driver use cpu_logical_map, export
> > __cpu_logical_map to fix build issue.
> >

I wonder why like other instances in the drivers, the mpidr is not get
directly from the cpu. The cpufreq_driver->init call happens when the cpu
is being brought online and is executed on the required cpu IIUC.

read_cpuid_mpidr() is inline and avoids having to export the logical_cpu_map.
Though we may not add physical hotplug anytime soon, less dependency
on this cpu_logical_map is better given that we can resolve this without
the need to access the map.

-- 
Regards,
Sudeep