When VDMA is configured for more than one frame in the h/w
for example h/w is configured for n number of frames and user
Submits n number of frames and triggered the DMA using issue_pending API.
In the current driver flow we are submitting one frame at a time
but we should submit all the n number of frames at one time as the h/w
Is configured for n number of frames.
This patch fixes this issue.
Signed-off-by: Kedareswara rao Appana <appanad@xxxxxxxxxx>
---
Changes for v2:
---> Fixed race conditions in the driver as suggested by Jose Abreu
---> Fixed unnecessray if else checks in the vdma_start_transfer
as suggested by Laurent Pinchart.
drivers/dma/xilinx/xilinx_dma.c | 54 +++++++++++++++++++++++------------------
1 file changed, 31 insertions(+), 23 deletions(-)
diff --git a/drivers/dma/xilinx/xilinx_dma.c b/drivers/dma/xilinx/xilinx_dma.c
index be7eb41..cf9edd8 100644
--- a/drivers/dma/xilinx/xilinx_dma.c
+++ b/drivers/dma/xilinx/xilinx_dma.c
@@ -1052,25 +1052,38 @@ static void xilinx_vdma_start_transfer(struct xilinx_dma_chan *chan)
if (chan->has_sg) {
dma_ctrl_write(chan, XILINX_DMA_REG_TAILDESC,
tail_segment->phys);
+ list_splice_tail_init(&chan->pending_list, &chan->active_list);
+ chan->desc_pendingcount = 0;
} else {
struct xilinx_vdma_tx_segment *segment, *last = NULL;
- int i = 0;
+ int i = 0, j = 0;
if (chan->desc_submitcount < chan->num_frms)
i = chan->desc_submitcount;
- list_for_each_entry(segment, &desc->segments, node) {
- if (chan->ext_addr)
- vdma_desc_write_64(chan,
- XILINX_VDMA_REG_START_ADDRESS_64(i++),
- segment->hw.buf_addr,
- segment->hw.buf_addr_msb);
- else
- vdma_desc_write(chan,
- XILINX_VDMA_REG_START_ADDRESS(i++),
- segment->hw.buf_addr);
-
- last = segment;
+ for (j = 0; j < chan->num_frms; ) {
+ list_for_each_entry(segment, &desc->segments, node) {
+ if (chan->ext_addr)
+ vdma_desc_write_64(chan,
+ XILINX_VDMA_REG_START_ADDRESS_64(i++),
+ segment->hw.buf_addr,
+ segment->hw.buf_addr_msb);
+ else
+ vdma_desc_write(chan,
+ XILINX_VDMA_REG_START_ADDRESS(i++),
+ segment->hw.buf_addr);
+
+ last = segment;
+ }
+ list_del(&desc->node);
+ list_add_tail(&desc->node, &chan->active_list);
+ j++;
+ if (list_empty(&chan->pending_list) ||
+ (i == chan->num_frms))
+ break;
+ desc = list_first_entry(&chan->pending_list,
+ struct xilinx_dma_tx_descriptor,
+ node);
}
if (!last)
@@ -1081,20 +1094,14 @@ static void xilinx_vdma_start_transfer(struct xilinx_dma_chan *chan)
vdma_desc_write(chan, XILINX_DMA_REG_FRMDLY_STRIDE,
last->hw.stride);
vdma_desc_write(chan, XILINX_DMA_REG_VSIZE, last->hw.vsize);
- }
- chan->idle = false;
- if (!chan->has_sg) {
- list_del(&desc->node);
- list_add_tail(&desc->node, &chan->active_list);
- chan->desc_submitcount++;
- chan->desc_pendingcount--;
+ chan->desc_submitcount += j;
+ chan->desc_pendingcount -= j;
if (chan->desc_submitcount == chan->num_frms)
chan->desc_submitcount = 0;
- } else {
- list_splice_tail_init(&chan->pending_list, &chan->active_list);
- chan->desc_pendingcount = 0;
}
+
+ chan->idle = false;
}
/**
@@ -1342,6 +1349,7 @@ static int xilinx_dma_reset(struct xilinx_dma_chan *chan)
chan->err = false;
chan->idle = true;
+ chan->desc_submitcount = 0;
return err;
}
--
2.1.2
--
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