diff options
| author | Dave Jiang <dave.jiang@intel.com> | 2020-05-13 20:47:49 +0200 |
|---|---|---|
| committer | Vinod Koul <vkoul@kernel.org> | 2020-06-17 16:15:14 +0200 |
| commit | 47ec7f09bc107720905c96bc37771e4ed1ff0aed (patch) | |
| tree | d0d500633ad1d51812bc8ed04394e16859bc296c /drivers/dma/idxd | |
| parent | dmaengine: mmp_tdma: share the IRQ line (diff) | |
| download | linux-47ec7f09bc107720905c96bc37771e4ed1ff0aed.tar.xz linux-47ec7f09bc107720905c96bc37771e4ed1ff0aed.zip | |
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 <swathi.kovvuri@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Tested-by: Swathi Kovvuri <swathi.kovvuri@intel.com>
Link: https://lore.kernel.org/r/158939557151.20335.12404113976045569870.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'drivers/dma/idxd')
| -rw-r--r-- | drivers/dma/idxd/dma.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/dma/idxd/dma.c b/drivers/dma/idxd/dma.c index c64c1429d160..0c892cbd72e0 100644 --- a/drivers/dma/idxd/dma.c +++ b/drivers/dma/idxd/dma.c @@ -133,7 +133,7 @@ static enum dma_status idxd_dma_tx_status(struct dma_chan *dma_chan, dma_cookie_t cookie, struct dma_tx_state *txstate) { - return dma_cookie_status(dma_chan, cookie, txstate); + return DMA_OUT_OF_ORDER; } /* @@ -174,6 +174,7 @@ int idxd_register_dma_device(struct idxd_device *idxd) INIT_LIST_HEAD(&dma->channels); dma->dev = &idxd->pdev->dev; + dma_cap_set(DMA_COMPLETION_NO_ORDER, dma->cap_mask); dma->device_release = idxd_dma_release; if (idxd->hw.opcap.bits[0] & IDXD_OPCAP_MEMMOVE) { |