[v3,09/11] dmaengine: dw-axi-dmac: try best to get residue when tx is running

Message ID 20230521101216.4084-10-jszhang@kernel.org
State New
Headers
Series dmaengine: dw-axi_dmac: bug fix clean up and more features |

Commit Message

Jisheng Zhang May 21, 2023, 10:12 a.m. UTC
  When tx is running, vchan_find_desc() will return NULL, try our best
to get the residue in this case.

Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
---
 drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)
  

Patch

diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
index f0bd8a7e3caf..f14fdfc9c7e9 100644
--- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
+++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
@@ -312,6 +312,7 @@  dma_chan_tx_status(struct dma_chan *dchan, dma_cookie_t cookie,
 		  struct dma_tx_state *txstate)
 {
 	struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
+	struct axi_dma_desc *desc = NULL;
 	struct virt_dma_desc *vdesc;
 	enum dma_status status;
 	u32 completed_length;
@@ -329,9 +330,15 @@  dma_chan_tx_status(struct dma_chan *dchan, dma_cookie_t cookie,
 
 	vdesc = vchan_find_desc(&chan->vc, cookie);
 	if (vdesc) {
-		length = vd_to_axi_desc(vdesc)->length;
-		completed_blocks = vd_to_axi_desc(vdesc)->completed_blocks;
-		len = vd_to_axi_desc(vdesc)->hw_desc[0].len;
+		desc = vd_to_axi_desc(vdesc);
+	} else if (chan->desc && chan->desc->vd.tx.cookie == cookie) {
+		desc = chan->desc;
+	}
+
+	if (desc) {
+		length = desc->length;
+		completed_blocks = desc->completed_blocks;
+		len = desc->hw_desc[0].len;
 		completed_length = completed_blocks * len;
 		bytes = length - completed_length;
 	}
@@ -432,6 +439,7 @@  static void axi_chan_block_xfer_start(struct axi_dma_chan *chan,
 	axi_chan_irq_set(chan, irq_mask);
 
 	axi_chan_enable(chan);
+	chan->desc = first;
 }
 
 static void axi_chan_start_first_queued(struct axi_dma_chan *chan)
@@ -1195,6 +1203,7 @@  static int dma_chan_terminate_all(struct dma_chan *dchan)
 	spin_unlock_irqrestore(&chan->vc.lock, flags);
 
 	vchan_dma_desc_free_list(&chan->vc, &head);
+	chan->desc = NULL;
 
 	dev_vdbg(dchan2dev(dchan), "terminated: %s\n", axi_chan_name(chan));