Return-path: Received: from mail.academy.zt.ua ([82.207.120.245]:21603 "EHLO mail.academy.zt.ua" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757188Ab1DLU0g (ORCPT ); Tue, 12 Apr 2011 16:26:36 -0400 Subject: Re: [RFC][PATCH] axi: add AXI bus driver From: George Kashperko To: Hauke Mehrtens Cc: balbi@ti.com, linux-wireless@vger.kernel.org, "John W. Linville" , b43-dev@lists.infradead.org, Michael =?ISO-8859-1?Q?B=FCsch?= , Larry Finger , Arend van Spriel , linux-arm-kernel@lists.infradead.org, Russell King , Arnd Bergmann , Andy Botting , linuxdriverproject , "linux-kernel@vger.kernel.org" In-Reply-To: <4DA4AC4B.90409@hauke-m.de> References: <1302566227-23788-1-git-send-email-zajec5@gmail.com> <20110412133633.GR15130@legolas.emea.dhcp.ti.com> <1302634039.14216.10.camel@dev.znau.edu.ua> <1302635550.14216.21.camel@dev.znau.edu.ua> <4DA4AC4B.90409@hauke-m.de> Content-Type: text/plain Date: Tue, 12 Apr 2011 23:23:30 +0300 Message-Id: <1302639810.14216.57.camel@dev.znau.edu.ua> Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: > The specification for the AMBA AXI Interface is available for free > download from ARM if you register to their website and accept their license: > http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.set.amba/index.html > I got it from there without any problems and the license does not look > too bad for me, by having a quick look at it. I do not know if it will > help you in any way or if it is completely unrelated. > > Why is the existing support for the amba bus not extended or used in any > way for this? It exists for some time in drivers/amba/. There already > was a discussion about this in https://lkml.org/lkml/2011/3/30/186 , but > with no result as I see. Existing AMBA bus might is the proper place to publish axi master port cores but Rafal's implementation manage those internally. Rafal introduces separate Broadcom-specific bus intended exclusively for Broadcom-specific devices management. Those devices share common identification/management techniques which are completely different from those implemented by other existant kernel buses and amba bus (at least at it current state) as well. Might be there are good and proper ways to extend amba bus driver to support axi as well but its a field for guys and girls confident with closed proprietary arm docs. Therefore IMHO the bus introduced by Rafal deserves its own driver and name. But I'm sure that the "axi" tag isn't good one for this bus. > > >>>> Also can't figure out how is this implementation supposed to manage > >>>> multicore devices. > >>> > >>> We have got ideas, but let's first find (wait for) such a device ;) > >> bcm4716 usb host ? Don't really know if there are any other multicores. > > > > This is SoC, we do not have any problems supporting multiple cores on > > SoCs. All cores are available at the same time, without any sliding > > windows. > > > > Hauke > -- > To unsubscribe from this list: send the line "unsubscribe linux-wireless" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Have nice day, George