From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sergei Shtylyov Subject: Re: [PATCH 6/13] devres: implement managed iomap interface Date: Thu, 10 Apr 2008 20:56:12 +0400 Message-ID: <47FE46AC.5000901@ru.mvista.com> References: <11684073371547-git-send-email-htejun@gmail.com> <47FA4FD2.8060808@ru.mvista.com> <47FB85CB.2070506@gmail.com> <47FB8751.3040301@ru.mvista.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <47FB8751.3040301@ru.mvista.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linuxppc-dev-bounces+glppd-linuxppc64-dev=m.gmane.org@ozlabs.org Errors-To: linuxppc-dev-bounces+glppd-linuxppc64-dev=m.gmane.org@ozlabs.org To: Tejun Heo Cc: linux-ide@vger.kernel.org, gregkh@suse.de, linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, jgarzik@pobox.com, alan@lxorguk.ukuu.org.uk List-Id: linux-ide@vger.kernel.org Hello, I wrote: >>> Those functions are going to break on 32-bit platforms with >>> extended physical address (well, that's starting with Pentiums which >>> had 36-bit PAE :-) AND devices mapped beyond 4 GB (e.g. PowerPC >>> 44x). You should have used resource_size_t for the 'offset' >>> parameter. As this most probably means that libata is broken on such >>> platforms, I'm going to submit a patch... > It's broken with drivers using MMIO, I meant to say. Oops, I meant PCI drivers here, at least for the time being. And it looks like that was a false alarm. :-] >> Yeah, right please go ahead. But I wonder whether any BIOS was >> actually crazy enough to map mmio region above 4G on 32bit machine. > This is a *hardware* mapping on some non-x86 platforms (like PPC 44x > or MIPS Alchemy). The arch/ppc/ and arch/mips/ kernels have special > hooks called from ioremap() which help create an illusion that the PCI > memory space on such platforms (not only it) is mapped below 4 GB; > arch/powerpc/ kernel doesn't do this anymore -- hence this newly > encountered issue. I thought that pcim_iomap() used devm_ioremap() or something -- which of course turned to be wrong. devm_ioremap() alone is yet safe since there are no users for it amongst PPC 44x platform device drivers... MBR, Sergei