From 47ec7f09bc107720905c96bc37771e4ed1ff0aed Mon Sep 17 00:00:00 2001 From: Dave Jiang Date: Wed, 13 May 2020 11:47:49 -0700 Subject: dmaengine: cookie bypass for out of order completion The cookie tracking in dmaengine expects all submissions completed in order. Some DMA devices like Intel DSA can complete submissions out of order, especially if configured with a work queue sharing multiple DMA engines. Add a status DMA_OUT_OF_ORDER that tx_status can be returned for those DMA devices. The user should use callbacks to track the completion rather than the DMA cookie. This would address the issue of dmatest complaining that descriptors are "busy" when the cookie count goes backwards due to out of order completion. Add DMA_COMPLETION_NO_ORDER DMA capability to allow the driver to flag the device's ability to complete operations out of order. Reported-by: Swathi Kovvuri Signed-off-by: Dave Jiang Tested-by: Swathi Kovvuri Link: https://lore.kernel.org/r/158939557151.20335.12404113976045569870.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Vinod Koul --- include/linux/dmaengine.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/linux') diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index e1c03339918f..9f9a13a2c01f 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -39,6 +39,7 @@ enum dma_status { DMA_IN_PROGRESS, DMA_PAUSED, DMA_ERROR, + DMA_OUT_OF_ORDER, }; /** @@ -61,6 +62,7 @@ enum dma_transaction_type { DMA_SLAVE, DMA_CYCLIC, DMA_INTERLEAVE, + DMA_COMPLETION_NO_ORDER, /* last transaction type for creation of the capabilities mask */ DMA_TX_TYPE_END, }; -- cgit v1.3-7-g2ca7