From: Maxime Ripard Date: Mon, 6 Jul 2015 10:19:23 +0000 (+0200) Subject: dmaengine: Add scatter-gathered memset X-Git-Tag: firefly_0821_release~176^2~1143^2~70 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=50c7cd2bd3786258606c6c7c8356064c08ab2383;p=firefly-linux-kernel-4.4.55.git dmaengine: Add scatter-gathered memset The current API allows the driver to accelerate memset by using the DMA controller. However, it does so over a contiguous memory area, which might proves inefficient when you have to do it over a non-contiguous yet repititive pattern, since you have to create a number of descriptors and then submit each other. Add a memset operation going over a scatter list to handle such cases in a single call. Signed-off-by: Maxime Ripard Acked-by: Ludovic Desroches Signed-off-by: Vinod Koul --- diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index 03ed832adbc2..8ad9a4e839f6 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -66,6 +66,7 @@ enum dma_transaction_type { DMA_XOR_VAL, DMA_PQ_VAL, DMA_MEMSET, + DMA_MEMSET_SG, DMA_INTERRUPT, DMA_SG, DMA_PRIVATE, @@ -630,6 +631,7 @@ enum dmaengine_alignment { * @device_prep_dma_pq: prepares a pq operation * @device_prep_dma_pq_val: prepares a pqzero_sum operation * @device_prep_dma_memset: prepares a memset operation + * @device_prep_dma_memset_sg: prepares a memset operation over a scatter list * @device_prep_dma_interrupt: prepares an end of chain interrupt operation * @device_prep_slave_sg: prepares a slave dma operation * @device_prep_dma_cyclic: prepare a cyclic dma operation suitable for audio. @@ -696,6 +698,9 @@ struct dma_device { struct dma_async_tx_descriptor *(*device_prep_dma_memset)( struct dma_chan *chan, dma_addr_t dest, int value, size_t len, unsigned long flags); + struct dma_async_tx_descriptor *(*device_prep_dma_memset_sg)( + struct dma_chan *chan, struct scatterlist *sg, + unsigned int nents, int value, unsigned long flags); struct dma_async_tx_descriptor *(*device_prep_dma_interrupt)( struct dma_chan *chan, unsigned long flags); struct dma_async_tx_descriptor *(*device_prep_dma_sg)(