linux-kernel - Re: [PATCH V2] cpuidle/powernv: Read target_residency value of idle states from DT if available

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]

Message-ID: <m3wq47w9jj.fsf@oc8180480414.ibm.com>
Date:	Wed, 28 Jan 2015 20:15:28 +1100
From:	Stewart Smith <stewart@...ux.vnet.ibm.com>
To:	Preeti U Murthy <preeti@...ux.vnet.ibm.com>, mpe@...erman.id.au
Cc:	rafael.j.wysocki@...el.com, linuxppc-dev@...ts.ozlabs.org,
	linux-kernel@...r.kernel.org, linux-pm@...r.kernel.org
Subject: Re: [PATCH V2] cpuidle/powernv: Read target_residency value of idle states from DT if available

Preeti U Murthy <preeti@...ux.vnet.ibm.com> writes:
> The device tree now exposes the residency values for different idle states. Read
> these values instead of calculating residency from the latency values. The values
> exposed in the DT are validated for optimal power efficiency. However to maintain
> compatibility with the older firmware code which does not expose residency
> values, use default values as a fallback mechanism. While at it, handle some
> cleanups.

>From a "I just merged the patch that exports these values from firmware"
point of view, using them and falling back looks good.

(I find the hardcoding of snooze in the driver a bit odd, as is the
hardcoding of max power states to 8 - which could bite us in the future
if a future processor has more states... but these aren't problems with
this patch)

Acked-by: Stewart Smith <stewart@...ux.vnet.ibm.com>

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/