Re: [PATCH v0 1/2] DMA: fsldma: Disable DMA_INTERRUPT when Async_tx enabled
From: Dan Williams <hidden>
Date: 2009-10-16 01:25:52
Also in:
linux-crypto, linux-raid, lkml
[ added Leo and Timur to the Cc ] On Wed, Oct 14, 2009 at 11:41 PM, Vishnu Suresh [off-list ref] wrot= e:
quoted hunk ↗ jump to hunk
This patch disables the use of DMA_INTERRUPT capability with Async_tx The fsldma produces a null transfer with DMA_INTERRUPT capability when used with Async_tx. When RAID devices queue a transaction via Async_tx, this =A0results in a hang. Signed-off-by: Vishnu Suresh <redacted> --- =A0drivers/dma/fsldma.c | =A0 =A06 ++++++ =A01 files changed, 6 insertions(+), 0 deletions(-)diff --git a/drivers/dma/fsldma.c b/drivers/dma/fsldma.c index 296f9e7..66d9b39 100644 --- a/drivers/dma/fsldma.c +++ b/drivers/dma/fsldma.c@@ -1200,7 +1200,13 @@ static int __devinit of_fsl_dma_probe(struct of_de=
vice *dev,
=A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 =A0 =A0 =A0 =A0- fdev->reg.start + 1);
=A0 =A0 =A0 =A0dma_cap_set(DMA_MEMCPY, fdev->common.cap_mask); +#ifndef CONFIG_ASYNC_CORE + =A0 =A0 =A0 /* + =A0 =A0 =A0 =A0* The DMA_INTERRUPT async_tx is a NULL transfer, which w=
ill
+ =A0 =A0 =A0 =A0* triger a PE interrupt. + =A0 =A0 =A0 =A0*/ =A0 =A0 =A0 =A0dma_cap_set(DMA_INTERRUPT, fdev->common.cap_mask); +#endif =A0 =A0 =A0 =A0dma_cap_set(DMA_SLAVE, fdev->common.cap_mask); =A0 =A0 =A0 =A0fdev->common.device_alloc_chan_resources =3D fsl_dma_alloc=
_chan_resources;
=A0 =A0 =A0 =A0fdev->common.device_free_chan_resources =3D fsl_dma_free_c=
han_resources; You are basically saying that fsl_dma_prep_interrupt() is buggy. Can that routine be fixed rather than this piecemeal solution? If it cannot be fixed (i.e. hardware issue) then fsl_dma_prep_interrupt() should just be disabled/deleted altogether. -- Dan