[PATCH net-next v5 05/10] dmaengine: xilinx_dma: Freeup active list based on descriptor completion bit

[Radhey Shyam Pandey]

AXIDMA IP in SG mode sets completion bit to 1 when the transfer is
completed. Read this bit to move descriptor from active list to the
done list. This feature is needed when interrupt delay timeout and
IRQThreshold is enabled i.e Dly_IrqEn is triggered w/o completing
interrupt threshold.

Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xxxxxxx>
---
Changes for v5:
- New patch in this series. Just a note that dmaengine series
  was earlier sent as separate series[1] and now it's merged
  with axiethernet series[2].
  [1]: https://lore.kernel.org/all/20221124102745.2620370-1-sarath.babu.naidu.gaddam@xxxxxxx
  [2]: https://lore.kernel.org/all/20230630053844.1366171-1-sarath.babu.naidu.gaddam@xxxxxxx
- Switch to amd.com email address.
---
 drivers/dma/xilinx/xilinx_dma.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/dma/xilinx/xilinx_dma.c b/drivers/dma/xilinx/xilinx_dma.c
index 7f3c57fbe1e3..3b721da827e0 100644
--- a/drivers/dma/xilinx/xilinx_dma.c
+++ b/drivers/dma/xilinx/xilinx_dma.c
@@ -177,6 +177,7 @@
 #define XILINX_DMA_CR_COALESCE_SHIFT	16
 #define XILINX_DMA_BD_SOP		BIT(27)
 #define XILINX_DMA_BD_EOP		BIT(26)
+#define XILINX_DMA_BD_COMP_MASK		BIT(31)
 #define XILINX_DMA_COALESCE_MAX		255
 #define XILINX_DMA_NUM_DESCS		512
 #define XILINX_DMA_NUM_APP_WORDS	5
@@ -1708,6 +1709,14 @@ static void xilinx_dma_complete_descriptor(struct xilinx_dma_chan *chan)
 		return;
 
 	list_for_each_entry_safe(desc, next, &chan->active_list, node) {
+		if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
+			struct xilinx_axidma_tx_segment *seg;
+
+			seg = list_last_entry(&desc->segments,
+					      struct xilinx_axidma_tx_segment, node);
+			if (!(seg->hw.status & XILINX_DMA_BD_COMP_MASK) && chan->has_sg)
+				break;
+		}
 		if (chan->has_sg && chan->xdev->dma_config->dmatype !=
 		    XDMA_TYPE_VDMA)
 			desc->residue = xilinx_dma_get_residue(chan, desc);
-- 
2.34.1