net/mlx5: allocate door-bells via DevX

[dpdk.git] / drivers / net / mlx5 / mlx5.c

diff --git a/drivers/net/mlx5/mlx5.c b/drivers/net/mlx5/mlx5.c
index fca2dbf..8c1bd32 100644 (file)
--- a/drivers/net/mlx5/mlx5.c
+++ b/drivers/net/mlx5/mlx5.c
@@ -1311,6 +1311,125 @@ exit:
        DRV_LOG(DEBUG, "min tx inline configured: %d", config->txq_inline_min);
 }
 
+/**
+ * Allocate page of door-bells and register it using DevX API.
+ *
+ * @param [in] dev
+ *   Pointer to Ethernet device.
+ *
+ * @return
+ *   Pointer to new page on success, NULL otherwise.
+ */
+static struct mlx5_devx_dbr_page *
+mlx5_alloc_dbr_page(struct rte_eth_dev *dev)
+{
+       struct mlx5_priv *priv = dev->data->dev_private;
+       struct mlx5_devx_dbr_page *page;
+
+       /* Allocate space for door-bell page and management data. */
+       page = rte_calloc_socket(__func__, 1, sizeof(struct mlx5_devx_dbr_page),
+                                RTE_CACHE_LINE_SIZE, dev->device->numa_node);
+       if (!page) {
+               DRV_LOG(ERR, "port %u cannot allocate dbr page",
+                       dev->data->port_id);
+               return NULL;
+       }
+       /* Register allocated memory. */
+       page->umem = mlx5_glue->devx_umem_reg(priv->sh->ctx, page->dbrs,
+                                             MLX5_DBR_PAGE_SIZE, 0);
+       if (!page->umem) {
+               DRV_LOG(ERR, "port %u cannot umem reg dbr page",
+                       dev->data->port_id);
+               rte_free(page);
+               return NULL;
+       }
+       return page;
+}
+
+/**
+ * Find the next available door-bell, allocate new page if needed.
+ *
+ * @param [in] dev
+ *   Pointer to Ethernet device.
+ * @param [out] dbr_page
+ *   Door-bell page containing the page data.
+ *
+ * @return
+ *   Door-bell address offset on success, a negative error value otherwise.
+ */
+int64_t
+mlx5_get_dbr(struct rte_eth_dev *dev, struct mlx5_devx_dbr_page **dbr_page)
+{
+       struct mlx5_priv *priv = dev->data->dev_private;
+       struct mlx5_devx_dbr_page *page = NULL;
+       uint32_t i, j;
+
+       LIST_FOREACH(page, &priv->dbrpgs, next)
+               if (page->dbr_count < MLX5_DBR_PER_PAGE)
+                       break;
+       if (!page) { /* No page with free door-bell exists. */
+               page = mlx5_alloc_dbr_page(dev);
+               if (!page) /* Failed to allocate new page. */
+                       return (-1);
+               LIST_INSERT_HEAD(&priv->dbrpgs, page, next);
+       }
+       /* Loop to find bitmap part with clear bit. */
+       for (i = 0;
+            i < MLX5_DBR_BITMAP_SIZE && page->dbr_bitmap[i] == UINT64_MAX;
+            i++)
+               ; /* Empty. */
+       /* Find the first clear bit. */
+       j = rte_bsf64(~page->dbr_bitmap[i]);
+       assert(i < (MLX5_DBR_PER_PAGE / 64));
+       page->dbr_bitmap[i] |= (1 << j);
+       page->dbr_count++;
+       *dbr_page = page;
+       return (((i * 64) + j) * sizeof(uint64_t));
+}
+
+/**
+ * Release a door-bell record.
+ *
+ * @param [in] dev
+ *   Pointer to Ethernet device.
+ * @param [in] umem_id
+ *   UMEM ID of page containing the door-bell record to release.
+ * @param [in] offset
+ *   Offset of door-bell record in page.
+ *
+ * @return
+ *   0 on success, a negative error value otherwise.
+ */
+int32_t
+mlx5_release_dbr(struct rte_eth_dev *dev, uint32_t umem_id, uint64_t offset)
+{
+       struct mlx5_priv *priv = dev->data->dev_private;
+       struct mlx5_devx_dbr_page *page = NULL;
+       int ret = 0;
+
+       LIST_FOREACH(page, &priv->dbrpgs, next)
+               /* Find the page this address belongs to. */
+               if (page->umem->umem_id == umem_id)
+                       break;
+       if (!page)
+               return -EINVAL;
+       page->dbr_count--;
+       if (!page->dbr_count) {
+               /* Page not used, free it and remove from list. */
+               LIST_REMOVE(page, next);
+               if (page->umem)
+                       ret = -mlx5_glue->devx_umem_dereg(page->umem);
+               rte_free(page);
+       } else {
+               /* Mark in bitmap that this door-bell is not in use. */
+               int i = offset / 64;
+               int j = offset % 64;
+
+               page->dbr_bitmap[i] &= ~(1 << j);
+       }
+       return ret;
+}
+
 /**
  * Spawn an Ethernet device from Verbs information.
  *