| Message ID | 1463064854-6719-1-git-send-email-ludovic.desroches@atmel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Le 12/05/2016 16:54, Ludovic Desroches a écrit : > Having descriptors aligned on 64 bits allows update CNDA and CUBC in an > atomic way. > > Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> > Fixes: e1f7c9eee707 ("dmaengine: at_xdmac: creation of the atmel > eXtended DMA Controller driver") > Cc: stable@vger.kernel.org #v4.1 and later Reviewed-by: Nicolas Ferre <nicolas.ferre@atmel.com> > --- > drivers/dma/at_xdmac.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c > index 8e304b1..ba9b0b7 100644 > --- a/drivers/dma/at_xdmac.c > +++ b/drivers/dma/at_xdmac.c > @@ -242,7 +242,7 @@ struct at_xdmac_lld { > u32 mbr_dus; /* Destination Microblock Stride Register */ > }; > > - > +/* 64-bit alignment needed to update CNDA and CUBC registers in an atomic way. */ > struct at_xdmac_desc { > struct at_xdmac_lld lld; > enum dma_transfer_direction direction; > @@ -253,7 +253,7 @@ struct at_xdmac_desc { > unsigned int xfer_size; > struct list_head descs_list; > struct list_head xfer_node; > -}; > +} __aligned(sizeof(u64)); > > static inline void __iomem *at_xdmac_chan_reg_base(struct at_xdmac *atxdmac, unsigned int chan_nb) > { >
On Thu, May 12, 2016 at 04:54:08PM +0200, Ludovic Desroches wrote: > Having descriptors aligned on 64 bits allows update CNDA and CUBC in an > atomic way. Applied all, thanks
diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c index 8e304b1..ba9b0b7 100644 --- a/drivers/dma/at_xdmac.c +++ b/drivers/dma/at_xdmac.c @@ -242,7 +242,7 @@ struct at_xdmac_lld { u32 mbr_dus; /* Destination Microblock Stride Register */ }; - +/* 64-bit alignment needed to update CNDA and CUBC registers in an atomic way. */ struct at_xdmac_desc { struct at_xdmac_lld lld; enum dma_transfer_direction direction; @@ -253,7 +253,7 @@ struct at_xdmac_desc { unsigned int xfer_size; struct list_head descs_list; struct list_head xfer_node; -}; +} __aligned(sizeof(u64)); static inline void __iomem *at_xdmac_chan_reg_base(struct at_xdmac *atxdmac, unsigned int chan_nb) {
Having descriptors aligned on 64 bits allows update CNDA and CUBC in an atomic way. Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> Fixes: e1f7c9eee707 ("dmaengine: at_xdmac: creation of the atmel eXtended DMA Controller driver") Cc: stable@vger.kernel.org #v4.1 and later --- drivers/dma/at_xdmac.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)