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: Sat, 10 Jan 2015 16:11:18 +0100 Message-ID: <20150110151118.GA16036@amd> References: <1420575219-27061-1-git-send-email-atull@opensource.altera.com> <1420575219-27061-3-git-send-email-atull@opensource.altera.com> <20150107084819.GA1887@amd> <20150109205643.GA5761@amd> <4D4EA2D5-68DD-49F7-9E2D-3A0A8F6AF9CA@konsulko.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Content-Disposition: inline In-Reply-To: <4D4EA2D5-68DD-49F7-9E2D-3A0A8F6AF9CA@konsulko.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: driverdev-devel-bounces@linuxdriverproject.org Sender: "devel" To: Pantelis Antoniou Cc: mark.rutland@arm.com, linux-doc@vger.kernel.org, rubini@gnudd.com, hpa@zytor.com, Steffen Trumtrar , devel@driverdev.osuosl.org, sameo@linux.intel.com, nico@linaro.org, ijc+devicetree@hellion.org.uk, Michal Simek , kyle.teske@ni.com, jgunthorpe@obsidianresearch.com, Grant Likely , davidb@codeaurora.org, Linus Walleij , cesarb@cesarb.net, devicetree@vger.kernel.org, jason@lakedaemon.net, pawel.moll@arm.com, iws@ovro.caltech.edu, atull , Mark Brown , philip@balister.org, dinguyen@opensource.altera.com, Michal Simek , Greg Kroah-Hartman , yvanderv@opensource.altera.com, Linux Kernel Mailing List , Felipe Balbi , Alan Tull List-Id: devicetree@vger.kernel.org T24gU2F0IDIwMTUtMDEtMTAgMTA6MTA6NTEsIFBhbnRlbGlzIEFudG9uaW91IHdyb3RlOgo+IEhp IFBhdmVsLAo+IAo+ID4gT24gSmFuIDksIDIwMTUsIGF0IDIyOjU2ICwgUGF2ZWwgTWFjaGVrIDxw YXZlbEBkZW54LmRlPiB3cm90ZToKPiA+IAo+ID4gT24gRnJpIDIwMTUtMDEtMDkgMTM6MTQ6MjQs IGF0dWxsIHdyb3RlOgo+ID4+IE9uIFdlZCwgNyBKYW4gMjAxNSwgUGF2ZWwgTWFjaGVrIHdyb3Rl Ogo+ID4+IAo+ID4+PiBPbiBUdWUgMjAxNS0wMS0wNiAxNDoxMzozNywgYXR1bGxAb3BlbnNvdXJj ZS5hbHRlcmEuY29tIHdyb3RlOgo+ID4+Pj4gKwo+ID4+Pj4gK1doYXQ6CQkvc3lzL2NsYXNzL2Zw Z2FfbWFuYWdlci88ZnBnYT4vZmlybXdhcmUKPiA+Pj4+ICtEYXRlOgkJT2N0b2JlciAyMDE0Cj4g Pj4+PiArS2VybmVsVmVyc2lvbjoJMy4xOAo+ID4+Pj4gK0NvbnRhY3Q6CUFsYW4gVHVsbCA8YXR1 bGxAb3BlbnNvdXJjZS5hbHRlcmEuY29tPgo+ID4+Pj4gK0Rlc2NyaXB0aW9uOglOYW1lIG9mIHRo ZSBGUEdBIGltYWdlIGZpbGUgdG8gbG9hZCB1c2luZyBmaXJtd2FyZQo+ID4+Pj4gY2xhc3MuCj4g Pj4+IAo+ID4+PiBUaGlzIG9uZSBpcyB1Z2x5OiBpdCB1bm5lY2Nlc3NhcmlseSBwYXNzZXMgZmly bXdhcmUgbmFtZSB0aHJvdWdoIHRoZQo+ID4+PiBrZXJuZWwuIEp1c3QgbWFrZSBpbnRlcmZhY2Ug YW5kIGNvZGUgc2ltcGxlciBieSBhbHdheXMgcGFzc2luZwo+ID4+PiAic29jZnBnYS1mcGdhLWlt YWdlIiBvciBzb21ldGhpbmcgbGlrZSB0aGF0Lgo+ID4+PiAKPiA+Pj4gVGhhbmtzLAo+ID4+PiAJ CQkJCQkJCQlQYXZlbAo+ID4+IAo+ID4+IEhpIFBhdmVsLAo+ID4+IAo+ID4+IEl0IG1pZ2h0IGJl IHVnbHkuICBJdCdzIG5vdCB1bm5lY2Vzc2FyeS4gIFNvbWUgdXNlcyBvZiBGUEdBcyBpbnZvbHZl Cj4gPj4gc3dpdGNoaW5nIG91dCB0aGUgRlBHQSBpbWFnZXMgZHluYW1pY2FsbHkgdW5kZXIgY29u dHJvbCBvZiB0aGUgdXNlcnNwYWNlLgo+ID4gCj4gPiBUaGVuIGNvbmZpZ3VyZSB1ZGV2IHRvIGxv YWQgcmlnaHQgZmlybXdhcmUgZm9yIHlvdSwgb3IgbG4gLXMKPiA+IGltYWdlLWktd2FudC1ub3cg c29jZnBnYS1mcGdhLWltYWdlIHRvIHNlbGVjdCB0aGUgb25lIHRvIHJlYWTigKY/Cj4gPiAKPiAK PiBXaG8gc2FpZCB0aGF0IHVkZXYgaXMgZ29pbmcgdG8gYmUgYXZhaWxhYmxlIGluIHRoZSBraW5k IG9mIHN5c3RlbSB0aGlzIGlzIGdvaW5nIHRvIGVuZCBpbj8KCk5vb25lLgoKPiBEb2luZyBsbiAt cyB0cmlja3MgdG8gbG9hZCBhIGRpZmZlcmVudCBpbWFnZT8gUmVhbGx5PwoKQnV0IGlmIHlvdSBk b24ndCBoYXZlIHVkZXYsIHlvdSBjYW4gZG8gbG4gLXMuIEl0IGlzIGJldHRlciB0aGFuCm9wZW4t Y29kaW5nIHN5bWxpbmsgZnVuY3Rpb25hbGl0eSBpbnRvCi9zeXMvY2xhc3MvZnBnYV9tYW5hZ2Vy LzxmcGdhPi9maXJtd2FyZSAuLi4gY2F1c2UgdGhhdCdzIHdoYXQgdGhpcyBpcy4KCkFjdHVhbGx5 LCBjbGVhbiBpbXBsZW1lbnRhdGlvbiBvZiAiZmlybXdhcmUiIHdvdWxkIGJlIHN5bWxpbmsgaW4K c3lzZnM7IGJ1dCBJJ2Qgc2F5IHRoYXQgd291bGQgYmUgb3ZlcmRvaW5nIGl0LgoKPiBJIHNheSB0 aGUgaW50ZXJmYWNlIGlzIGZpbmUgYXMgaXQgaXMuCgpJIHNheSBpdCBpcyBub3QuCgkJCQkJCQkJ CVBhdmVsCi0tIAooZW5nbGlzaCkgaHR0cDovL3d3dy5saXZlam91cm5hbC5jb20vfnBhdmVsbWFj aGVrCihjZXNreSwgcGljdHVyZXMpIGh0dHA6Ly9hdHJleS5rYXJsaW4ubWZmLmN1bmkuY3ovfnBh dmVsL3BpY3R1cmUvaG9yc2VzL2Jsb2cuaHRtbApfX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fXwpkZXZlbCBtYWlsaW5nIGxpc3QKZGV2ZWxAbGludXhkcml2ZXJw cm9qZWN0Lm9yZwpodHRwOi8vZHJpdmVyZGV2LmxpbnV4ZHJpdmVycHJvamVjdC5vcmcvbWFpbG1h bi9saXN0aW5mby9kcml2ZXJkZXYtZGV2ZWwK From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753942AbbAJPLX (ORCPT ); Sat, 10 Jan 2015 10:11:23 -0500 Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:49386 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753255AbbAJPLV (ORCPT ); Sat, 10 Jan 2015 10:11:21 -0500 Date: Sat, 10 Jan 2015 16:11:18 +0100 From: Pavel Machek To: Pantelis Antoniou Cc: atull , Greg Kroah-Hartman , jgunthorpe@obsidianresearch.com, hpa@zytor.com, Michal Simek , Michal Simek , rdunlap@infradead.org, 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, akpm@linux-foundation.org, 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: <20150110151118.GA16036@amd> References: <1420575219-27061-1-git-send-email-atull@opensource.altera.com> <1420575219-27061-3-git-send-email-atull@opensource.altera.com> <20150107084819.GA1887@amd> <20150109205643.GA5761@amd> <4D4EA2D5-68DD-49F7-9E2D-3A0A8F6AF9CA@konsulko.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <4D4EA2D5-68DD-49F7-9E2D-3A0A8F6AF9CA@konsulko.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat 2015-01-10 10:10:51, Pantelis Antoniou wrote: > Hi Pavel, > > > On Jan 9, 2015, at 22:56 , Pavel Machek wrote: > > > > On Fri 2015-01-09 13:14:24, atull wrote: > >> On Wed, 7 Jan 2015, Pavel Machek wrote: > >> > >>> On Tue 2015-01-06 14:13:37, atull@opensource.altera.com wrote: > >>>> + > >>>> +What: /sys/class/fpga_manager//firmware > >>>> +Date: October 2014 > >>>> +KernelVersion: 3.18 > >>>> +Contact: Alan Tull > >>>> +Description: Name of the FPGA image file to load using firmware > >>>> class. > >>> > >>> This one is ugly: it unneccessarily passes firmware name through the > >>> kernel. Just make interface and code simpler by always passing > >>> "socfpga-fpga-image" or something like that. > >>> > >>> Thanks, > >>> Pavel > >> > >> Hi Pavel, > >> > >> It might be ugly. It's not unnecessary. Some uses of FPGAs involve > >> switching out the FPGA images dynamically under control of the userspace. > > > > Then configure udev to load right firmware for you, or ln -s > > image-i-want-now socfpga-fpga-image to select the one to read…? > > > > Who said that udev is going to be available in the kind of system this is going to end in? Noone. > Doing ln -s tricks to load a different image? Really? But if you don't have udev, you can do ln -s. It is better than open-coding symlink functionality into /sys/class/fpga_manager//firmware ... cause that's what this is. Actually, clean implementation of "firmware" would be symlink in sysfs; but I'd say that would be overdoing it. > I say the interface is fine as it is. I say it is not. Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html