amd-xgbe: Simplify the Rx desciptor ring tracking

Make the Rx descriptor ring processing similar to the Tx descriptor
ring processing.  Remove the realloc_index and realloc_threshold
variables and base everything on the current index counter and the
dirty index counter.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 25 insertions, 43 deletions

diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-desc.c b/drivers/net/ethernet/amd/xgbe/xgbe-desc.c
index a50891f52197..d81fc6bd4759 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe-desc.c
+++ b/drivers/net/ethernet/amd/xgbe/xgbe-desc.c
@@ -422,7 +422,6 @@ static void xgbe_wrapper_rx_descriptor_init(struct xgbe_prv_data *pdata)
 
                 ring->cur = 0;
                 ring->dirty = 0;
-                memset(&ring->rx, 0, sizeof(ring->rx));
 
                 hw_if->rx_desc_init(channel);
         }
@@ -621,35 +620,6 @@ err_out:
         return 0;
 }
 
-static void xgbe_realloc_rx_buffer(struct xgbe_channel *channel)
-{
-        struct xgbe_prv_data *pdata = channel->pdata;
-        struct xgbe_hw_if *hw_if = &pdata->hw_if;
-        struct xgbe_ring *ring = channel->rx_ring;
-        struct xgbe_ring_data *rdata;
-        int i;
-
-        DBGPR("-->xgbe_realloc_rx_buffer: rx_ring->rx.realloc_index = %u\n",
-              ring->rx.realloc_index);
-
-        for (i = 0; i < ring->dirty; i++) {
-                rdata = XGBE_GET_DESC_DATA(ring, ring->rx.realloc_index);
-
-                /* Reset rdata values */
-                xgbe_unmap_rdata(pdata, rdata);
-
-                if (xgbe_map_rx_buffer(pdata, ring, rdata))
-                        break;
-
-                hw_if->rx_desc_reset(rdata);
-
-                ring->rx.realloc_index++;
-        }
-        ring->dirty = 0;
-
-        DBGPR("<--xgbe_realloc_rx_buffer\n");
-}
-
 void xgbe_init_function_ptrs_desc(struct xgbe_desc_if *desc_if)
 {
         DBGPR("-->xgbe_init_function_ptrs_desc\n");
@@ -657,7 +627,7 @@ void xgbe_init_function_ptrs_desc(struct xgbe_desc_if *desc_if)
         desc_if->alloc_ring_resources = xgbe_alloc_ring_resources;
         desc_if->free_ring_resources = xgbe_free_ring_resources;
         desc_if->map_tx_skb = xgbe_map_tx_skb;
-        desc_if->realloc_rx_buffer = xgbe_realloc_rx_buffer;
+        desc_if->map_rx_buffer = xgbe_map_rx_buffer;
         desc_if->unmap_rdata = xgbe_unmap_rdata;
         desc_if->wrapper_tx_desc_init = xgbe_wrapper_tx_descriptor_init;
         desc_if->wrapper_rx_desc_init = xgbe_wrapper_rx_descriptor_init;
diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-drv.c b/drivers/net/ethernet/amd/xgbe/xgbe-drv.c
index bdb373c87050..e2f560ff5104 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe-drv.c
+++ b/drivers/net/ethernet/amd/xgbe/xgbe-drv.c
@@ -225,6 +225,11 @@ static inline unsigned int xgbe_tx_avail_desc(struct xgbe_ring *ring)
         return (ring->rdesc_count - (ring->cur - ring->dirty));
 }
 
+static inline unsigned int xgbe_rx_dirty_desc(struct xgbe_ring *ring)
+{
+        return (ring->cur - ring->dirty);
+}
+
 static int xgbe_maybe_stop_tx_queue(struct xgbe_channel *channel,
                                     struct xgbe_ring *ring, unsigned int count)
 {
@@ -1775,15 +1780,28 @@ struct net_device_ops *xgbe_get_netdev_ops(void)
 static void xgbe_rx_refresh(struct xgbe_channel *channel)
 {
         struct xgbe_prv_data *pdata = channel->pdata;
+        struct xgbe_hw_if *hw_if = &pdata->hw_if;
         struct xgbe_desc_if *desc_if = &pdata->desc_if;
         struct xgbe_ring *ring = channel->rx_ring;
         struct xgbe_ring_data *rdata;
 
-        desc_if->realloc_rx_buffer(channel);
+        while (ring->dirty != ring->cur) {
+                rdata = XGBE_GET_DESC_DATA(ring, ring->dirty);
+
+                /* Reset rdata values */
+                desc_if->unmap_rdata(pdata, rdata);
+
+                if (desc_if->map_rx_buffer(pdata, ring, rdata))
+                        break;
+
+                hw_if->rx_desc_reset(rdata);
+
+                ring->dirty++;
+        }
 
         /* Update the Rx Tail Pointer Register with address of
          * the last cleaned entry */
-        rdata = XGBE_GET_DESC_DATA(ring, ring->rx.realloc_index - 1);
+        rdata = XGBE_GET_DESC_DATA(ring, ring->dirty - 1);
         XGMAC_DMA_IOWRITE(channel, DMA_CH_RDTR_LO,
                           lower_32_bits(rdata->rdesc_dma));
 }
@@ -1933,7 +1951,7 @@ static int xgbe_rx_poll(struct xgbe_channel *channel, int budget)
 read_again:
                 rdata = XGBE_GET_DESC_DATA(ring, ring->cur);
 
-                if (ring->dirty > (XGBE_RX_DESC_CNT >> 3))
+                if (xgbe_rx_dirty_desc(ring) > (XGBE_RX_DESC_CNT >> 3))
                         xgbe_rx_refresh(channel);
 
                 if (hw_if->dev_read(channel))
@@ -1941,7 +1959,6 @@ read_again:
 
                 received++;
                 ring->cur++;
-                ring->dirty++;
 
                 incomplete = XGMAC_GET_BITS(packet->attributes,
                                             RX_PACKET_ATTRIBUTES,
diff --git a/drivers/net/ethernet/amd/xgbe/xgbe.h b/drivers/net/ethernet/amd/xgbe/xgbe.h
index 2af6affc35a7..e6ee64e1d6ec 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe.h
+++ b/drivers/net/ethernet/amd/xgbe/xgbe.h
@@ -361,8 +361,7 @@ struct xgbe_ring {
          *  cur   - Tx: index of descriptor to be used for current transfer
          *          Rx: index of descriptor to check for packet availability
          *  dirty - Tx: index of descriptor to check for transfer complete
-         *          Rx: count of descriptors in which a packet has been received
-         *              (used with skb_realloc_index to refresh the ring)
+         *          Rx: index of descriptor to check for buffer reallocation
          */
         unsigned int cur;
         unsigned int dirty;
@@ -377,11 +376,6 @@ struct xgbe_ring {
                         unsigned short cur_mss;
                         unsigned short cur_vlan_ctag;
                 } tx;
-
-                struct {
-                        unsigned int realloc_index;
-                        unsigned int realloc_threshold;
-                } rx;
         };
 } ____cacheline_aligned;
 
@@ -596,7 +590,8 @@ struct xgbe_desc_if {
         int (*alloc_ring_resources)(struct xgbe_prv_data *);
         void (*free_ring_resources)(struct xgbe_prv_data *);
         int (*map_tx_skb)(struct xgbe_channel *, struct sk_buff *);
-        void (*realloc_rx_buffer)(struct xgbe_channel *);
+        int (*map_rx_buffer)(struct xgbe_prv_data *, struct xgbe_ring *,
+                             struct xgbe_ring_data *);
         void (*unmap_rdata)(struct xgbe_prv_data *, struct xgbe_ring_data *);
         void (*wrapper_tx_desc_init)(struct xgbe_prv_data *);
         void (*wrapper_rx_desc_init)(struct xgbe_prv_data *);