From mboxrd@z Thu Jan 1 00:00:00 1970 From: Martin Peres Subject: Re: [PATCH] radeon: Make PM info available to all, not just debug users Date: Mon, 04 Jun 2012 17:02:04 +0200 Message-ID: <4FCCCDEC.8010400@free.fr> References: <20120602190858.335065e1.cand@gmx.com> <4FCB4266.80907@vodafone.de> <20120604114431.aeeda075.cand@gmx.com> <4FCC9C56.2000505@vodafone.de> <4FCCACBD.4030401@free.fr> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1"; Format="flowed" Content-Transfer-Encoding: quoted-printable Return-path: Received: from smtp6-g21.free.fr (smtp6-g21.free.fr [212.27.42.6]) by gabe.freedesktop.org (Postfix) with ESMTP id 6E2C89E949 for ; Mon, 4 Jun 2012 08:02:36 -0700 (PDT) In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dri-devel-bounces+sf-dri-devel=m.gmane.org@lists.freedesktop.org Errors-To: dri-devel-bounces+sf-dri-devel=m.gmane.org@lists.freedesktop.org To: Jerome Glisse Cc: cand@gmx.com, dri-devel@lists.freedesktop.org List-Id: dri-devel@lists.freedesktop.org Le 04/06/2012 16:31, Jerome Glisse a =E9crit : > > I don't think sysfs is the way to go, i am pretty sure that power > management will change drasticly again in the future especialy btw > discret and integrated GPU. I would rather have hardware specific > ioctl. > > Cheers, > Jerome Any particular idea of what may change? The proposed interface would work even on entirely dynamic reclocking (per-domain frequency scaling) as opposed to perflvl-based reclocking. It is unlikely to happen though. A more realistic possibility could be that engines would be reclocked independently according to their internal load. If that was to happen, then the already-existing API could be used as a master control and engines could specify the performance level policy they want (follow master, always min, always max, conservative, dynamic). I'm pretty sure voltage domains will soon appear but I don't see what could possibly be changed that wouldn't be covered by what I proposed. As for the reason we would like to use IOCTLs instead of sysfs, I really don't understand what is the rationale. I personally want to empower the users to let them decide what is best for them. Sysfs is way easier to work with! Although my idea may be sketchy, I am dead-serious about coming up with a good API. Martin