Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753669AbaFUSuy (ORCPT ); Sat, 21 Jun 2014 14:50:54 -0400 Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:45895 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750936AbaFUSux (ORCPT ); Sat, 21 Jun 2014 14:50:53 -0400 Date: Sat, 21 Jun 2014 20:50:51 +0200 From: Pavel Machek To: Ilia Mirkin Cc: kernel list , Ben Skeggs , Greg KH , Alexandre Courbot , David Airlie , "dri-devel@lists.freedesktop.org" Subject: Re: unparseable, undocumented /sys/class/drm/.../pstate Message-ID: <20140621185051.GA25094@amd.pavel.ucw.cz> References: <20140621180201.GA4621@amd.pavel.ucw.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat 2014-06-21 14:22:59, Ilia Mirkin wrote: > On Sat, Jun 21, 2014 at 2:02 PM, Pavel Machek wrote: > > Hi! > > > > AFAICT, pstate file will contain something like > > > > 07: core 100 MHz memory 123 MHz * > > 08: core 100-200 MHz memory 123 MHz > > > > ...which does not look exactly like one-value-per-file, and I'm pretty > > sure userspace will get it wrong if it tries to parse it. Plus, I > > don't see required documentation in Documentation/ABI. ... > > FTR, this file has been in place since 3.13, and there was a different > file before it (performance_levels), with a comparable format since > much earlier (definitely 3.8, probably earlier). I think it's meant > a According to the article, it is only starting to work now. I know articles can be wrong, but I don't have that hardware... Sorry if it is the case. > lot more for people looking at it and echo'ing stuff to it to modify > the levels (where supported), than for programs parsing it. Perhaps > sysfs is the wrong place for this -- what is the right place? debugfs? debugfs would work, yes. Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/