linux-mips
[Top] [All Lists]

Re: [PATCH][MIPS] add DMA declare coherent memory support

To: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Subject: Re: [PATCH][MIPS] add DMA declare coherent memory support
From: Yuasa Yoichi <yoichi_yuasa@tripeaks.co.jp>
Date: Fri, 5 Jun 2009 12:03:01 +0900
Cc: Ralf Baechle <ralf@linux-mips.org>, linux-mips <linux-mips@linux-mips.org>
Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:sender:received:in-reply-to :references:date:x-google-sender-auth:message-id:subject:from:to:cc :content-type:content-transfer-encoding; bh=Uan6n2NW90DtOUoZYPgKYM7eh0GWpRs7gPQc4Mqt3c8=; b=ckv9DFiKeGhjymEvTrBGPDlA4pi+UKx3MVrdwymClPNE+QvYNooTg9o6dnEVLzyN8T Guq96gK5tnjMTyT1h6195DONtd/mnA8qsAkLgbQtMVU6Lc1WrVrvJkezl2FMUZzCsi2w 0AO5+U5SkwqPQu5Z2gOVsyxDheO5P+7RyvZbI=
Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type :content-transfer-encoding; b=gmscSxXM4K5pYjGAyg1P22SIiG8tbP3Nrn4vusAtpzDmHy/oVehv+J1WbfkpsVxxxb fWDNLMuWxdWF4Ol1EypEv5dNSZJUFTbn2DPAd5Q++99MPTlctUl3puNCUZusEmxOkohx vKeJq5oYTtYfbbULyOVoyv7/ufObkK1i7hQYE=
In-reply-to: <20090603153151.GA4009@alpha.franken.de>
Original-recipient: rfc822;linux-mips@linux-mips.org
References: <20090604001604.9ced2997.yoichi_yuasa@tripeaks.co.jp> <20090603153151.GA4009@alpha.franken.de>
Sender: linux-mips-bounce@linux-mips.org
Hi,

2009/6/4 Thomas Bogendoerfer <tsbogend@alpha.franken.de>:
> On Thu, Jun 04, 2009 at 12:16:04AM +0900, Yoichi Yuasa wrote:
>>
>> Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
>
> a little bit more description what this is all about would be quite
> helpful. I also see a problem as there is at least one MIPS machine
> (SGI IP28), which doesn't support coherent memory (at least not without
> playing dirty games with the memory controller, which in return makes
> the machine slow).

Some drivers require dma_declare_coherent_memory() (eg.
drivers/usb/host/ohci-sm501.c).
It is used to driver's local memory allocation with dma_alloc_coherent().

Yoichi

<Prev in Thread] Current Thread [Next in Thread>