From mboxrd@z Thu Jan 1 00:00:00 1970 From: santosh.shilimkar@ti.com (Santosh Shilimkar) Date: Wed, 22 Jan 2014 09:39:26 -0500 Subject: [PATCH RFC 08/26] dmaengine: omap-dma: consolidate setup of CCR In-Reply-To: <20140122141905.GQ27282@n2100.arm.linux.org.uk> References: <20140102150836.GA3826@n2100.arm.linux.org.uk> <52DFBFDD.8040506@ti.com> <20140122141905.GQ27282@n2100.arm.linux.org.uk> Message-ID: <52DFD81E.1070103@ti.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Wednesday 22 January 2014 09:19 AM, Russell King - ARM Linux wrote: > On Wed, Jan 22, 2014 at 06:25:57PM +0530, Sricharan R wrote: >> Setting up of DMA_DST_SYNC_PREFETCH is missing after this ? > > I'm not looking for the DMA engine driver to be a 100% reimplementation > of the legacy driver. Rather than supporting the entire set of features > which the legacy driver did, and have many of them simply not used, the > approach I'm taking here is to only support what is necessary for the > drivers we have in mainline - and what fits the DMA engine interfaces. > +1 on the approach. > There is no point inventing new DMA engine interfaces for features for > which we have no users in mainline kernel - to try to do that will be > quite rightfully thrown out by the DMA engine maintainers. > > Here's the total number of references/definitions of DMA_DST_SYNC_PREFETCH > in the mainline kernel: > > arch/arm/plat-omap/dma.c: if (src_or_dst_synch == OMAP_DMA_DST_SYNC_PREFETCH) { > include/linux/omap-dma.h:#define OMAP_DMA_DST_SYNC_PREFETCH 0x02 > > Hence, this feature is unused at present. > I thought the crypto was using the prefetch feature but it isn't. Regards, Santosh