From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sascha Hauer Subject: Re: dma_declare_coherent_memory on main memory Date: Mon, 10 Dec 2018 08:26:48 +0100 Message-ID: <20181210072648.ore6xttedsgpndi4@pengutronix.de> References: <20181207153432.GA24917@lst.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20181207153432.GA24917@lst.de> Sender: linux-kernel-owner@vger.kernel.org To: Christoph Hellwig Cc: Shawn Guo , Fabio Estevam , linux-arm-kernel@lists.infradead.org, iommu@lists.linux-foundation.org, linux-imx@nxp.com, linux-kernel@vger.kernel.org, linux-sh@vger.kernel.org List-Id: iommu@lists.linux-foundation.org On Fri, Dec 07, 2018 at 04:34:32PM +0100, Christoph Hellwig wrote: > Hi all, > > the ARM imx27/31 ports and various sh boards use > dma_declare_coherent_memory on main memory taken from the memblock > allocator. > > Is there any good reason these couldn't be switched to CMA areas? > Getting rid of these magic dma_declare_coherent_memory area would > help making the dma allocator a lot simpler. At least for i.MX27/31 I'd say this predates CMA support, so historical reasons. Sascha -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |