linux-kernel - Re: [PATCH] cpufreq: Add Kryo CPU scaling driver

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 22 May 2018 15:08:03 +0530
From:   Viresh Kumar <viresh.kumar@...aro.org>
To:     ilialin@...eaurora.org
Cc:     'Sudeep Holla' <sudeep.holla@....com>, mturquette@...libre.com,
        sboyd@...nel.org, robh@...nel.org, mark.rutland@....com, nm@...com,
        lgirdwood@...il.com, broonie@...nel.org, andy.gross@...aro.org,
        david.brown@...aro.org, catalin.marinas@....com,
        will.deacon@....com, rjw@...ysocki.net, linux-clk@...r.kernel.org,
        devicetree@...r.kernel.org, linux-kernel@...r.kernel.org,
        linux-pm@...r.kernel.org, linux-arm-msm@...r.kernel.org,
        linux-soc@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
        rnayak@...eaurora.org, amit.kucheria@...aro.org,
        nicolas.dechesne@...aro.org, celster@...eaurora.org,
        tfinkel@...eaurora.org
Subject: Re: [PATCH] cpufreq: Add Kryo CPU scaling driver

On 22-05-18, 10:59, ilialin@...eaurora.org wrote:
> OK, I think I found out the way. Would this be correct?
> -----------------------------------------------------------------------------------------------
> extern struct cpu_topology cpu_topology[NR_CPUS];
> 
> static struct device *qcom_cpufreq_kryo_get_cluster_lead(int cluster)
> {
> 	unsigned cpu;
> 
> 	for_each_possible_cpu(cpu) {
> 		if ((cluster == cpu_topology[cpu].cluster_id) &&
> 			(0 == cpu_topology[cpu].core_id))
> 			return get_cpu_device(cpu);
> 	}
> 
> 	return NULL;
> }

Okay, this is what you should do IMHO.

for_each_possible_cpu(cpu) {
        cpu_dev = xxx..
        ret = dev_pm_opp_set_supported_hw(cpu_dev, xxx, xxx);
        if (ret && ret != -EBUSY)
                error-out.
}

This would require a trivial patch for the OPP core to not throw an
error message with -EBUSY. I can do that separately.

-- 
viresh