From mboxrd@z Thu Jan 1 00:00:00 1970 From: s.hauer@pengutronix.de (Sascha Hauer) Date: Mon, 30 Aug 2010 14:55:56 +0200 Subject: [PATCH 3/3 v2] dmaengine: Add Freescale i.MX SDMA support In-Reply-To: References: <1281956870-12463-1-git-send-email-s.hauer@pengutronix.de> <20100823174852.GB26928@pengutronix.de> <201008281727.10913.marek.vasut@gmail.com> <20100828161858.GI1473@pengutronix.de> Message-ID: <20100830125556.GL1473@pengutronix.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Sun, Aug 29, 2010 at 02:35:01PM +0200, Linus Walleij wrote: > 2010/8/28 Sascha Hauer : > > > Peripherals integrated into a SoC like the SDMA engine here are > > normally accessible in native endianess and thus need the __raw_* > > functions. > > So the SDMA actually switch and twist around the endianness of > its registers if it's synthesized into a bigendian version of the system? > > Or hardware-dynamically even depending on the setting of the > endianness bit in the ARM core? I think it's the bus between the ARM core and the periherals which changes the endianess. I have never tried running an i.MX in big endian mode, so I can only guess how the system really behaves in BE mode. 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 |