From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pavel Machek Subject: Re: [PATCH v8 2/4] fpga manager: add sysfs interface document Date: Tue, 17 Feb 2015 20:17:27 +0100 Message-ID: <20150217191727.GA18429@amd> References: <20150113222450.GA17475@obsidianresearch.com> <20150115184726.GA23247@obsidianresearch.com> <20150115204502.591bca1d@lxorguk.ukuu.org.uk> <20150121160151.453ba403@lxorguk.ukuu.org.uk> <20150121202700.GB4942@obsidianresearch.com> <20150215224006.GA5626@amd> <54E37569.80508@landley.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <54E37569.80508@landley.net> Sender: linux-kernel-owner@vger.kernel.org To: Rob Landley Cc: Jason Gunthorpe , Pantelis Antoniou , One Thousand Gnomes , atull , Greg Kroah-Hartman , hpa@zytor.com, Michal Simek , Michal Simek , Randy Dunlap , Linux Kernel Mailing List , devicetree@vger.kernel.org, robh+dt@kernel.org, Grant Likely , iws@ovro.caltech.edu, linux-doc@vger.kernel.org, Mark Brown , philip@balister.org, rubini@gnudd.com, Steffen Trumtrar , jason@lakedaemon.net, kyle.teske@ni.com, nico@linaro.org, Felipe Balbi , m.chehab@samsung.com, davidb@codeaurora.org, davem@davemloft.net, cesarb@cesarb.net, sameo@linux.intel.com, Andrew List-Id: devicetree@vger.kernel.org On Tue 2015-02-17 11:07:53, Rob Landley wrote: > > > On 02/15/2015 04:40 PM, Pavel Machek wrote: > > On Wed 2015-01-21 13:27:00, Jason Gunthorpe wrote: > >> On Wed, Jan 21, 2015 at 06:33:12PM +0200, Pantelis Antoniou wrote: > >> My point is that the current firmware layer is overly cautious and > >> FPGAs are very big. My current project on small Xilinx device has a > >> 10MB programming file. The biggest Xilinx device today has a max > >> bitfile size around 122MB. > >> > >> So keeping that much memory pinned in the kernel when I can prove it > >> is uncessary for my system (either because there is no suspend/resume > >> possibility, or because I know the CPU can always access the > >> filesytem) is very undesirable. > > > > Well, your current device aalso has 1GB RAM, no? > > Unnecessarily pinning 10% of your ram is a good solution? Never said that. But I'd rather have _some_ API proposed, then try to design in everthing including kitchen sink and do nothing. Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html