From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1764294AbdEAQl5 (ORCPT ); Mon, 1 May 2017 12:41:57 -0400 Received: from mx1.redhat.com ([209.132.183.28]:52868 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753526AbdEAQlz (ORCPT ); Mon, 1 May 2017 12:41:55 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 9074214BFD4 Authentication-Results: ext-mx04.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx04.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=jglisse@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 9074214BFD4 Date: Mon, 1 May 2017 12:41:51 -0400 From: Jerome Glisse To: One Thousand Gnomes Cc: Alan Tull , "Luebbers, Enno" , Moritz Fischer , Wu Hao , linux-fpga@vger.kernel.org, Linux Kernel Mailing List , "Kang, Luwei" , "Zhang, Yi Z" Subject: Re: [PATCH 00/16] Intel FPGA Device Drivers Message-ID: <20170501164149.GA18314@redhat.com> References: <20170412132919.GA16072@redhat.com> <20170412153746.GA17158@redhat.com> <20170414194817.GA27424@eluebber-mac02.jf.intel.com> <20170414204955.GA4805@redhat.com> <20170417155723.GA4547@redhat.com> <20170418143606.5685e7bc@lxorguk.ukuu.org.uk> <20170418145906.GA7069@redhat.com> <20170425210225.178f767c@lxorguk.ukuu.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20170425210225.178f767c@lxorguk.ukuu.org.uk> User-Agent: Mutt/1.8.0 (2017-02-23) X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Mon, 01 May 2017 16:41:55 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 25, 2017 at 09:02:25PM +0100, One Thousand Gnomes wrote: > > That is where we disagree. I do not see bitstream as firmware. For instance > > now you can run OpenCL on some FPGA, so this is exactly like GPU we should > > request open source stack from OpenCL down to bitstream. > > It's an accelerator with a bunch of firmwares where you load the right > one. We've got lots of those in Linux already. Your GPU probably needs > firmware as well in just the same way. I stress again OpenCL on FPGA ie at runtime you load a program source that is compiled at runtime and then lower to a bitstream which get loaded on the FGPA at runtime. You can go look at how OpenCL works it is not like fix firmware. OpenCL was done for GPU and everything needed to support OpenCL is open source when it comes to GPU. On contrary with FPGA the bitstream part is close source. Sure GPU have firmware, those firmware run on realtime micro-controller to dispatch job, handle GPU power management and other janitorial stuff. For some GPU we even have open source firmware. So FPGA with thing like OpenCL are more like GPU than like a fix hardware that is program once and use like a device for which we need a firmware. That is where we disagree on the characterization of things. > > For me this is not enough (tool to load bitstream). > > Unfortunately that isn't likely to change for any major FPGA device in > the near future. If you could load arbitrary bit patterns into an FPGA > then in most cases that also means you could physically destroy the > hardware. I am just questioning the different standard in the kernel. Jérôme