async_tx: build-time toggling of async_{syndrome,xor}_val dma support
ioat3.2 does not support asynchronous error notifications which makes
the driver experience latencies when non-zero pq validate results are
expected. Provide a mechanism for turning off async_xor_val and
async_syndrome_val via Kconfig. This approach is generally useful for
any driver that specifies ASYNC_TX_DISABLE_CHANNEL_SWITCH and would like
to force the async_tx api to fall back to the synchronous path for
certain operations.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index 5903a88..b401dad 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -26,6 +26,8 @@
select DMA_ENGINE
select DCA
select ASYNC_TX_DISABLE_CHANNEL_SWITCH
+ select ASYNC_TX_DISABLE_PQ_VAL_DMA
+ select ASYNC_TX_DISABLE_XOR_VAL_DMA
help
Enable support for the Intel(R) I/OAT DMA engine present
in recent Intel Xeon chipsets.
