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, 13 Jan 2015 08:56:51 +0100 Message-ID: <20150113075651.GB11760@amd> References: <20150107084819.GA1887@amd> <20150109205643.GA5761@amd> <4D4EA2D5-68DD-49F7-9E2D-3A0A8F6AF9CA@konsulko.com> <20150110151118.GA16036@amd> <20150112084530.GA28681@amd> <20150113072857.GA11760@amd> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Content-Disposition: inline In-Reply-To: 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 T24gVHVlIDIwMTUtMDEtMTMgMDk6NDA6MTgsIFBhbnRlbGlzIEFudG9uaW91IHdyb3RlOgo+IEhp IFBhdmVsLAo+IAo+ID4gT24gSmFuIDEzLCAyMDE1LCBhdCAwOToyOCAsIFBhdmVsIE1hY2hlayA8 cGF2ZWxAZGVueC5kZT4gd3JvdGU6Cj4gPiAKPiA+IEhpIQo+ID4gCj4gPj4+Pj4+Pj4+PiArV2hh dDoJCS9zeXMvY2xhc3MvZnBnYV9tYW5hZ2VyLzxmcGdhPi9maXJtd2FyZQo+ID4+Pj4+Pj4+Pj4g K0RhdGU6CQlPY3RvYmVyIDIwMTQKPiA+Pj4+Pj4+Pj4+ICtLZXJuZWxWZXJzaW9uOgkzLjE4Cj4g Pj4+Pj4+Pj4+PiArQ29udGFjdDoJQWxhbiBUdWxsIDxhdHVsbEBvcGVuc291cmNlLmFsdGVyYS5j b20+Cj4gPj4+Pj4+Pj4+PiArRGVzY3JpcHRpb246CU5hbWUgb2YgdGhlIEZQR0EgaW1hZ2UgZmls ZSB0byBsb2FkIHVzaW5nIGZpcm13YXJlCj4gPj4+Pj4+Pj4+PiBjbGFzcy4KPiA+Pj4+Pj4+Pj4g Cj4gPj4+Pj4+Pj4+IFRoaXMgb25lIGlzIHVnbHk6IGl0IHVubmVjY2Vzc2FyaWx5IHBhc3NlcyBm aXJtd2FyZSBuYW1lIHRocm91Z2ggdGhlCj4gPj4+Pj4+Pj4+IGtlcm5lbC4gSnVzdCBtYWtlIGlu dGVyZmFjZSBhbmQgY29kZSBzaW1wbGVyIGJ5IGFsd2F5cyBwYXNzaW5nCj4gPj4+Pj4+Pj4+ICJz b2NmcGdhLWZwZ2EtaW1hZ2UiIG9yIHNvbWV0aGluZyBsaWtlIHRoYXQuCj4gPiAuLi4KPiA+IAo+ ID4+PiBXaGF0IGlzIGN1bWJlcnNvbWUgYWJvdXQgc3ltbGluaz8gV2h5IGlzICJmYWtlIiBzeW1s aW5rIGluIHN5c2ZzIGJldHRlcj8KPiA+Pj4gCj4gPj4+PiBQcmV2aW91cyB1c2VzIG9mIHRoZSBm aXJtd2FyZSBsYXllciBoYXMgYmVlbiB0byB1c2UgaXQgdG8gbG9hZCBvbmNlIGFmdGVyCj4gPj4+ PiBib290dXA7IHRoaXMgaXMgZGlmZmVyZW50IHNpbmNlIHNvbWUgdXNlIGNhc2VzIHdpbGwgd2Fu dCB0byBzd2l0Y2ggb3V0Cj4gPj4+PiB0aGUgRlBHQSBpbWFnZS4gIElmIHNvbWVvbmUgd2FudHMg dGhlcmUgdG8gYmUgb25seSBvbmUgRlBHQSBpbWFnZSBvbgo+ID4+Pj4gdGhlIEZHUEEgZm9yZXZl ciwgdGhleSB3aWxsIHByb2JhYmx5IG5vdCBiZSB1c2luZyB0aGlzIGZyYW1ld29yazsgdGhlaXIK PiA+Pj4+IEZQR0Egd2lsbCBwcm9iYWJseSBiZSBsb2FkZWQgYmVmb3JlIExpbnV4IGJvb3RzIHVw Lgo+ID4+PiAKPiA+Pj4gV2h5PyBJIGhhdmUganVzdCBvbmUgaW1hZ2Ugb24gdGhlIGZwZ2EsIGFu ZCB3b3VsZCBwcmVmZXIgdG8gbG9hZCBpdAo+ID4+PiBmcm9tIExpbnV4Lgo+ID4+IAo+ID4+IFBh dmVsOiBUaGVzZSBwYXRjaGVzIHRhcmdldCBzdGFnaW5nIGFuZCBzeXNmcyBpbnRlcmZhY2UgZG9l c24ndCBuZWVkIHRvIGJlIHN0YWJsZQo+ID4+IGF0IHRoaXMgdGltZS4gSSB3b3VsZCBwcmVmZXIg dG8gYWRkIHRoZXNlIHBhdGNoZXMgdG8gc3RhZ2luZyBmb3IgMy4yMAo+ID4+IGFuZCBmZWVsIGZy ZWUgdG8gc2VuZCB0aGUgcGF0Y2ggd2hpY2ggZml4IHRoaXMuCj4gPiAKPiA+IEludGVyZXN0aW5n IHdheSB0byBhZGRyZXNzIHBhdGNoIHJldmlldy4gIldlJ2xsIG1lcmdlIGl0LCBhbmQgeW91IGNh bgo+ID4gZml4IGl0IHVwIGxhdGVyIi4KPiA+IAo+ID4+IFdpdGggeW91ciBjb2RlIHdpbGwgYmUg ZXhhY3RseSBjbGVhciBob3cgeW91IHdhbnQgdG8gdXNlIGl0IGFuZCB3ZSBjYW4KPiA+PiB0YWxr IGFib3V0IGl0Lgo+ID4gCj4gPiBJJ20gcHJldHR5IHN1cmUgQWxhbiBrbm93cyB3aGF0IEkgd2Fu dCBhdCB0aGlzIHBvaW50LCBoZSBqdXN0IGRvZXMgbm90Cj4gPiB3YW50IHRvIGRvIGl0Lgo+ID4g Cj4gPiBGb3IgdGhlIHJlY29yZCwgSSB3YW50IHRvIGRyb3AgImZpcm13YXJlIiBmaWxlLCB1c2Ug Zml4ZWQgZmlybXdhcmUKPiA+IG5hbWUsIGFuZCBkZWFsIHdpdGggbXVsdGlwbGUgZmlybXdhcmVz IGluIHVzZXJzcGFjZSAodXNpbmcgc3ltbGluayBvcgo+ID4gdWRldiBtYWdpYykuCj4gCj4gVGhh dOKAmXMgY29tcGxldGVseSBib2d1cy4gVXNpbmcgYSBmaXhlZCBmaXJtd2FyZSBmaWxlIGRvZXMg bm90IHJlc3BvbmQgdG8KPiByZWFsIHdvcmxkIHVzYWdlLCBhbmQgdGhlcmUgYXJlIG5vIHdvcmRz IHRvIGRlc2NyaWJlIHRoZSBoYWNrcyB1c2luZwo+IHN5bWxpbmtzIGFuZCB1ZGV2IGluIGFuIGVt YmVkZGVkIHByb2R1Y3QuCgo+ID4gSSBiZWxpZXZlIHRoaXMgaXMgc2ltcGxlc3Qgc29sdXRpb24s IHNob3VsZCBiZSBhZGVxdWF0ZSwgYW5kIGlzCj4gPiBjZXJ0YWlubHkgbGVzcyB1Z2x5IHRoYW4g aW1wbGVtZW50aW5nIGZha2Ugc3ltbGluayBpbgo+ID4gL3N5cy8uLi4vZmlybXdhcmUuIEFuZCBJ IGhhdmUgeWV0IHRvIGhlYXIgd2hhdCBpcyB3cm9uZyB3aXRoIHRoYXQKPiA+IHN1Z2dlc3Rpb24u Cj4gCj4gRXZlcnl0aGluZy4KCkNhbiB5b3UgYmUgbW9yZSBzcGVjaWZpYz8gQ3VycmVudCBzb2x1 dGlvbiBhbHJlYWR5IGhhcyBhIGZha2Ugc3ltbGluaywKaW1wbGVtZW50ZWQgYmFkbHkuCgpKdXN0 IHJlbW92ZSBpdCwgYW5kIHVzZSByZWFsIHN5bWxpbmsgKGFuZCB0aGVuIHlvdSBjYW4gb3B0aW9u YWxseQp0aGluayBvZiBzb21ldGhpbmcgYmV0dGVyLi4uKQoKCgkJCQkJCQkJCVBhdmVsCi0tIAoo ZW5nbGlzaCkgaHR0cDovL3d3dy5saXZlam91cm5hbC5jb20vfnBhdmVsbWFjaGVrCihjZXNreSwg cGljdHVyZXMpIGh0dHA6Ly9hdHJleS5rYXJsaW4ubWZmLmN1bmkuY3ovfnBhdmVsL3BpY3R1cmUv aG9yc2VzL2Jsb2cuaHRtbApfX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fXwpkZXZlbCBtYWlsaW5nIGxpc3QKZGV2ZWxAbGludXhkcml2ZXJwcm9qZWN0Lm9yZwpo dHRwOi8vZHJpdmVyZGV2LmxpbnV4ZHJpdmVycHJvamVjdC5vcmcvbWFpbG1hbi9saXN0aW5mby9k cml2ZXJkZXYtZGV2ZWwK From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751481AbbAMH45 (ORCPT ); Tue, 13 Jan 2015 02:56:57 -0500 Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:52622 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750963AbbAMH4z (ORCPT ); Tue, 13 Jan 2015 02:56:55 -0500 Date: Tue, 13 Jan 2015 08:56:51 +0100 From: Pavel Machek To: Pantelis Antoniou Cc: Michal Simek , atull , Greg Kroah-Hartman , jgunthorpe@obsidianresearch.com, hpa@zytor.com, 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: <20150113075651.GB11760@amd> References: <20150107084819.GA1887@amd> <20150109205643.GA5761@amd> <4D4EA2D5-68DD-49F7-9E2D-3A0A8F6AF9CA@konsulko.com> <20150110151118.GA16036@amd> <20150112084530.GA28681@amd> <20150113072857.GA11760@amd> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: 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 Tue 2015-01-13 09:40:18, Pantelis Antoniou wrote: > Hi Pavel, > > > On Jan 13, 2015, at 09:28 , Pavel Machek wrote: > > > > Hi! > > > >>>>>>>>>> +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. > > ... > > > >>> What is cumbersome about symlink? Why is "fake" symlink in sysfs better? > >>> > >>>> Previous uses of the firmware layer has been to use it to load once after > >>>> bootup; this is different since some use cases will want to switch out > >>>> the FPGA image. If someone wants there to be only one FPGA image on > >>>> the FGPA forever, they will probably not be using this framework; their > >>>> FPGA will probably be loaded before Linux boots up. > >>> > >>> Why? I have just one image on the fpga, and would prefer to load it > >>> from Linux. > >> > >> Pavel: These patches target staging and sysfs interface doesn't need to be stable > >> at this time. I would prefer to add these patches to staging for 3.20 > >> and feel free to send the patch which fix this. > > > > Interesting way to address patch review. "We'll merge it, and you can > > fix it up later". > > > >> With your code will be exactly clear how you want to use it and we can > >> talk about it. > > > > I'm pretty sure Alan knows what I want at this point, he just does not > > want to do it. > > > > For the record, I want to drop "firmware" file, use fixed firmware > > name, and deal with multiple firmwares in userspace (using symlink or > > udev magic). > > That’s completely bogus. Using a fixed firmware file does not respond to > real world usage, and there are no words to describe the hacks using > symlinks and udev in an embedded product. > > I believe this is simplest solution, should be adequate, and is > > certainly less ugly than implementing fake symlink in > > /sys/.../firmware. And I have yet to hear what is wrong with that > > suggestion. > > Everything. Can you be more specific? Current solution already has a fake symlink, implemented badly. Just remove it, and use real symlink (and then you can optionally think of something better...) Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html