[PATCH v3 8/8] dma/cnxk: fix last index return value

[Amit Prakash Shukla]

From: Vamsi Attunuru <vattun...@marvell.com>

last index value might lost the order when dma stats are reset
in between copy operations. Patch adds a variable to track the
completed count, that can be used to compute the last index, also
patch adds misc other fixes.

Signed-off-by: Vamsi Attunuru <vattun...@marvell.com>
---
v2:
- Fix for bugs observed in v1.
- Squashed few commits.

v3:
- Resolved review suggestions.
- Code improvement.

 drivers/dma/cnxk/cnxk_dmadev.c | 17 ++++++++++-------
 drivers/dma/cnxk/cnxk_dmadev.h |  1 +
 2 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/drivers/dma/cnxk/cnxk_dmadev.c b/drivers/dma/cnxk/cnxk_dmadev.c
index 288606bb3d..7e728b943b 100644
--- a/drivers/dma/cnxk/cnxk_dmadev.c
+++ b/drivers/dma/cnxk/cnxk_dmadev.c
@@ -298,6 +298,7 @@ cnxk_dmadev_start(struct rte_dma_dev *dev)
                }
 
                cnxk_stats_reset(dev, i);
+               dpi_conf->completed_offset = 0;
        }
 
        roc_dpi_enable(&dpivf->rdpi);
@@ -479,7 +480,7 @@ cnxk_dmadev_copy(void *dev_private, uint16_t vchan, 
rte_iova_t src, rte_iova_t d
                dpi_conf->pending++;
        }
 
-       return (dpi_conf->desc_idx++);
+       return dpi_conf->desc_idx++;
 }
 
 static int
@@ -545,13 +546,13 @@ cnxk_dmadev_copy_sg(void *dev_private, uint16_t vchan, 
const struct rte_dma_sge
        if (flags & RTE_DMA_OP_FLAG_SUBMIT) {
                rte_wmb();
                plt_write64(num_words, dpivf->rdpi.rbase + DPI_VDMA_DBELL);
-               dpi_conf->stats.submitted += nb_src;
+               dpi_conf->stats.submitted++;
        } else {
                dpi_conf->pnum_words += num_words;
                dpi_conf->pending++;
        }
 
-       return (dpi_conf->desc_idx++);
+       return dpi_conf->desc_idx++;
 }
 
 static int
@@ -664,13 +665,13 @@ cn10k_dmadev_copy_sg(void *dev_private, uint16_t vchan, 
const struct rte_dma_sge
        if (flags & RTE_DMA_OP_FLAG_SUBMIT) {
                rte_wmb();
                plt_write64(num_words, dpivf->rdpi.rbase + DPI_VDMA_DBELL);
-               dpi_conf->stats.submitted += nb_src;
+               dpi_conf->stats.submitted++;
        } else {
                dpi_conf->pnum_words += num_words;
                dpi_conf->pending++;
        }
 
-       return (dpi_conf->desc_idx++);
+       return dpi_conf->desc_idx++;
 }
 
 static uint16_t
@@ -700,7 +701,7 @@ cnxk_dmadev_completed(void *dev_private, uint16_t vchan, 
const uint16_t nb_cpls,
        }
 
        dpi_conf->stats.completed += cnt;
-       *last_idx = dpi_conf->stats.completed - 1;
+       *last_idx = (dpi_conf->completed_offset + dpi_conf->stats.completed - 
1) & 0xffff;
 
        return cnt;
 }
@@ -729,7 +730,7 @@ cnxk_dmadev_completed_status(void *dev_private, uint16_t 
vchan, const uint16_t n
        }
 
        dpi_conf->stats.completed += cnt;
-       *last_idx = dpi_conf->stats.completed - 1;
+       *last_idx = (dpi_conf->completed_offset + dpi_conf->stats.completed - 
1) & 0xffff;
 
        return cnt;
 }
@@ -814,6 +815,7 @@ cnxk_stats_reset(struct rte_dma_dev *dev, uint16_t vchan)
        if (vchan == RTE_DMA_ALL_VCHAN) {
                for (i = 0; i < dpivf->num_vchans; i++) {
                        dpi_conf = &dpivf->conf[i];
+                       dpi_conf->completed_offset += dpi_conf->stats.completed;
                        dpi_conf->stats = (struct rte_dma_stats){0};
                }
 
@@ -824,6 +826,7 @@ cnxk_stats_reset(struct rte_dma_dev *dev, uint16_t vchan)
                return -EINVAL;
 
        dpi_conf = &dpivf->conf[vchan];
+       dpi_conf->completed_offset += dpi_conf->stats.completed;
        dpi_conf->stats = (struct rte_dma_stats){0};
 
        return 0;
diff --git a/drivers/dma/cnxk/cnxk_dmadev.h b/drivers/dma/cnxk/cnxk_dmadev.h
index 9c6c898d23..254e7fea20 100644
--- a/drivers/dma/cnxk/cnxk_dmadev.h
+++ b/drivers/dma/cnxk/cnxk_dmadev.h
@@ -41,6 +41,7 @@ struct cnxk_dpi_conf {
        uint16_t desc_idx;
        uint16_t pad0;
        struct rte_dma_stats stats;
+       uint64_t completed_offset;
 };
 
 struct cnxk_dpi_vf_s {
-- 
2.25.1