From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sergei Shtylylov Subject: Re: + fix-ide-dma-resource-managment.patch added to -mm tree Date: Mon, 27 Mar 2006 16:57:24 +0400 Message-ID: <4427E134.5040802@ru.mvista.com> References: <200603212323.k2LNNSnJ006228@shell0.pdx.osdl.net> <58cb370e0603261309p126fdc64j1140bbf437ffe06e@mail.gmail.com> <4427C467.5030300@ru.mvista.com> <58cb370e0603270407v3329fa74n8148638a331b8419@mail.gmail.com> <4427D8DF.5000905@ru.mvista.com> <58cb370e0603270433q4f23f08andfc39b3f85ab4d5e@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from rtsoft2.corbina.net ([85.21.88.2]:9883 "HELO mail.dev.rtsoft.ru") by vger.kernel.org with SMTP id S1751003AbWC0M7L (ORCPT ); Mon, 27 Mar 2006 07:59:11 -0500 In-Reply-To: <58cb370e0603270433q4f23f08andfc39b3f85ab4d5e@mail.gmail.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Bartlomiej Zolnierkiewicz Cc: alan@lxorguk.ukuu.org.uk, linux-ide@vger.kernel.org Hello. Bartlomiej Zolnierkiewicz wrote: >>>On 3/27/06, Sergei Shtylylov wrote: [skipped] >>>>>>- release the same number of DMA I/O ports that was requested by a driver >>>>>please fix trm290.c to use ->mmio == 2 instead >>>> It's a _really_ old chipset (pre SFF-8038i) and has _no_ memory mapped >>>>regs AFAIK... >>>->mmio == 2 means _only_ that host driver is responsible >>>for reserving/releasing resources - it doesn't mean that host driver >>>is using MMIO (a bit confusing but this is what the current code does) >> So, your point is that ide_setup_dma() should _never_ do anything for the >>(mmio == 2) case? Maybe it shouldn't even be called? I guess we surely need > No, my point is that for ->mmio == 2 core code may not try to manage > IO or MMIO resources, only that. Note that I didn't try to. :-) Your 1st NAK was because I moved ide_release_dma_engine() above that (mmio == 2) check in ide_release_dma() -- which as we've now concluded is perfectly correct, isn't it? > ide_setup_dma() call is still needed for calling ide_allocate_dma_engine() Er, looking at sgiioc4.c, I somewhat doubt it -- since that driver allocates DMA engine of the _different_ size all by itself... However, the driver cleanup function might be called just before releasing the engine in ide-dma.c, so this approach sounds reasonable. :-) > and setting up ->dma_* / ->ide_dma_* fields. Yeah, it seems I've forgotten about them a bit... :-) [skipped] Another question: ide_setup_dma() is not supposed to be called by non-PCI driver, yes? It's just I know one (not in the community yet) that does... :-/ > Bartlomiej WBR, Sergei