Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755177AbbBQSNe (ORCPT ); Tue, 17 Feb 2015 13:13:34 -0500 Received: from quartz.orcorp.ca ([184.70.90.242]:57387 "EHLO quartz.orcorp.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753571AbbBQSNc (ORCPT ); Tue, 17 Feb 2015 13:13:32 -0500 Date: Tue, 17 Feb 2015 11:12:19 -0700 From: Jason Gunthorpe To: Pavel Machek Cc: 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, Rob Landley , davem@davemloft.net, cesarb@cesarb.net, sameo@linux.intel.com, Andrew Morton , Linus Walleij , pawel.moll@arm.com, mark.rutland@arm.com, ijc+devicetree@hellion.org.uk, galak@codeaurora.org, devel@driverdev.osuosl.org, Alan Tull , dinguyen@opensource.altera.com, yvanderv@opensource.altera.com Subject: Re: [PATCH v8 2/4] fpga manager: add sysfs interface document Message-ID: <20150217181219.GA27658@obsidianresearch.com> 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> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150215224006.GA5626@amd> User-Agent: Mutt/1.5.21 (2010-09-15) X-Broken-Reverse-DNS: no host name found for IP address 10.0.0.183 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1089 Lines: 27 On Sun, Feb 15, 2015 at 11:40:06PM +0100, Pavel Machek wrote: > > 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? No, certainly not. 256MB - the board only has space for two x16 DDR3 chips, and at design time 1GBit was about the biggest that could be reasonably obtained. It is also using a Zynq chip for management and the next firmware spin is likely to throw away 50% of that space to enable Xilinx's narrow ECC scheme on the ram. The Linux environment requires only about 40M of ram for runtime, as it was designed for systems with only 64M of ram, so even the 128M is overkill. Jason -- 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/