From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from akado.ru (fe02x03-cgp.akado.ru [77.232.31.165]) by ozlabs.org (Postfix) with ESMTP id 652EC2C0081 for ; Sun, 23 Sep 2012 06:17:38 +1000 (EST) Date: Sun, 23 Sep 2012 00:17:24 +0400 (MSK) From: malc To: Benjamin Herrenschmidt Subject: Re: Probing for native availability of isel from userspace In-Reply-To: <1348343737.1132.74.camel@pasglop> Message-ID: References: <50EE7AAC-3080-4B1B-B741-E3F7F5A57A73@kernel.crashing.org> <20120922102151.GA31314@visitor2.iram.es> <1348343737.1132.74.camel@pasglop> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Cc: linuxppc-dev@lists.ozlabs.org, hollis@penguinppc.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Sun, 23 Sep 2012, Benjamin Herrenschmidt wrote: > On Sat, 2012-09-22 at 21:08 +0200, Segher Boessenkool wrote: > > > Thanks for suggestion, but i'd rather not play with heuristics. > > > > Have a look at /sys/kernel/debug/powerpc/emulated_instructions/ then? > > Userspace should *NEVER* rely on the content of debugfs, it will change > with time, it is not a guaranteed ABI, it's purely for people to look > at... for debugging. Furthermore this box simply doesn't have it built-in... > > Unfortunately we don't expose ISEL support via features (maybe we > should, this is reasonably easy to fix, except that we are running short > on feature bits and adding a new set of bits isn't totally trivial). > > At this stage I would recommend using arch 2.06 as your key/trigger and > either add a handful of known PVR values (mfpvr is emulated) for other > CPUs you know support it (there shouldn't be that many), or just do the > heuristic :-( > Thank you. -- mailto:av1474@comtv.ru