@@ -333,6 +333,7 @@ dw_edma_device_transfer(struct dw_edma_transfer *xfer)
struct dw_edma_chunk *chunk;
struct dw_edma_burst *burst;
struct dw_edma_desc *desc;
+ size_t fsz = 0;
u32 cnt = 0;
int i;
@@ -382,9 +383,7 @@ dw_edma_device_transfer(struct dw_edma_transfer *xfer)
if (xfer->xfer.sg.len < 1)
return NULL;
} else if (xfer->type == EDMA_XFER_INTERLEAVED) {
- if (!xfer->xfer.il->numf)
- return NULL;
- if (xfer->xfer.il->numf > 0 && xfer->xfer.il->frame_size > 0)
+ if (!xfer->xfer.il->numf || xfer->xfer.il->frame_size < 1)
return NULL;
if (!xfer->xfer.il->src_inc || !xfer->xfer.il->dst_inc)
return NULL;
@@ -414,10 +413,8 @@ dw_edma_device_transfer(struct dw_edma_transfer *xfer)
cnt = xfer->xfer.sg.len;
sg = xfer->xfer.sg.sgl;
} else if (xfer->type == EDMA_XFER_INTERLEAVED) {
- if (xfer->xfer.il->numf > 0)
- cnt = xfer->xfer.il->numf;
- else
- cnt = xfer->xfer.il->frame_size;
+ cnt = xfer->xfer.il->numf * xfer->xfer.il->frame_size;
+ fsz = xfer->xfer.il->frame_size;
}
for (i = 0; i < cnt; i++) {
@@ -439,7 +436,7 @@ dw_edma_device_transfer(struct dw_edma_transfer *xfer)
else if (xfer->type == EDMA_XFER_SCATTER_GATHER)
burst->sz = sg_dma_len(sg);
else if (xfer->type == EDMA_XFER_INTERLEAVED)
- burst->sz = xfer->xfer.il->sgl[i].size;
+ burst->sz = xfer->xfer.il->sgl[i % fsz].size;
chunk->ll_region.sz += burst->sz;
desc->alloc_sz += burst->sz;
@@ -482,10 +479,9 @@ dw_edma_device_transfer(struct dw_edma_transfer *xfer)
if (xfer->type == EDMA_XFER_SCATTER_GATHER) {
sg = sg_next(sg);
- } else if (xfer->type == EDMA_XFER_INTERLEAVED &&
- xfer->xfer.il->frame_size > 0) {
+ } else if (xfer->type == EDMA_XFER_INTERLEAVED) {
struct dma_interleaved_template *il = xfer->xfer.il;
- struct data_chunk *dc = &il->sgl[i];
+ struct data_chunk *dc = &il->sgl[i % fsz];
src_addr += burst->sz;
if (il->src_sgl)
The interleaved DMA transfer support added in commit 85e7518f42c8 ("dmaengine: dw-edma: Add device_prep_interleave_dma() support") seems contradicting to what the DMA-engine defines. The next conditional statements: if (!xfer->xfer.il->numf) return NULL; if (xfer->xfer.il->numf > 0 && xfer->xfer.il->frame_size > 0) return NULL; basically mean that numf can't be zero and frame_size must always be zero, otherwise the transfer won't be executed. But further the transfer execution method takes the frames size from the dma_interleaved_template.sgl[] array for each frame. That array in accordance with [1] is supposed to be of dma_interleaved_template.frame_size size, which as we discovered before the code expects to be zero. So judging by the dw_edma_device_transfer() implementation the method implies the dma_interleaved_template.sgl[] array being of dma_interleaved_template.numf size, which is wrong. Since the dw_edma_device_transfer() method doesn't permit dma_interleaved_template.frame_size being non-zero then actual multi-chunk interleaved transfer turns to be unsupported even though the code implies having it supported. Let's fix that by adding a fully functioning support of the interleaved DMA transfers. First of all dma_interleaved_template.frame_size is supposed to be greater or equal to one thus having at least simple linear chunked frames. Secondly we can create a walk-through all over the chunks and frames just by initializing the number of the eDMA burst transactios as a multiple of dma_interleaved_template.numf and dma_interleaved_template.frame_size and getting the frame_size-modulo of the iteration step as an index of the dma_interleaved_template.sgl[] array. The rest of the dw_edma_device_transfer() method code can be left unchanged. [1] include/linux/dmaengine.h: doc struct dma_interleaved_template Fixes: 85e7518f42c8 ("dmaengine: dw-edma: Add device_prep_interleave_dma() support") Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru> Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> Tested-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> --- drivers/dma/dw-edma/dw-edma-core.c | 18 +++++++----------- 1 file changed, 7 insertions(+), 11 deletions(-)