net: airoha: Enable Rx Scatter-Gather

EN7581 SoC can receive 9k frames. Enable the reception of Scatter-Gather
(SG) frames.

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250304-airoha-eth-rx-sg-v1-2-283ebc61120e@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/airoha/airoha_eth.c b/drivers/net/ethernet/airoha/airoha_eth.c
index a9ed3fc2b5195f6b1868e65e1b8c0e5ef99e920f..54a239ab10aaac4a7bfc52977589415936207962 100644 (file)
--- a/drivers/net/ethernet/airoha/airoha_eth.c
+++ b/drivers/net/ethernet/airoha/airoha_eth.c
@@ -615,10 +615,10 @@ static int airoha_qdma_rx_process(struct airoha_queue *q, int budget)
                struct airoha_qdma_desc *desc = &q->desc[q->tail];
                u32 hash, reason, msg1 = le32_to_cpu(desc->msg1);
                dma_addr_t dma_addr = le32_to_cpu(desc->addr);
+               struct page *page = virt_to_head_page(e->buf);
                u32 desc_ctrl = le32_to_cpu(desc->ctrl);
                struct airoha_gdm_port *port;
-               struct sk_buff *skb;
-               int len, p;
+               int data_len, len, p;
 
                if (!(desc_ctrl & QDMA_DESC_DONE_MASK))
                        break;
@@ -636,30 +636,41 @@ static int airoha_qdma_rx_process(struct airoha_queue *q, int budget)
                dma_sync_single_for_cpu(eth->dev, dma_addr,
                                        SKB_WITH_OVERHEAD(q->buf_size), dir);
 
+               data_len = q->skb ? q->buf_size
+                                 : SKB_WITH_OVERHEAD(q->buf_size);
+               if (data_len < len)
+                       goto free_frag;
+
                p = airoha_qdma_get_gdm_port(eth, desc);
-               if (p < 0 || !eth->ports[p]) {
-                       page_pool_put_full_page(q->page_pool,
-                                               virt_to_head_page(e->buf),
-                                               true);
-                       continue;
-               }
+               if (p < 0 || !eth->ports[p])
+                       goto free_frag;
 
                port = eth->ports[p];
-               skb = napi_build_skb(e->buf, q->buf_size);
-               if (!skb) {
-                       page_pool_put_full_page(q->page_pool,
-                                               virt_to_head_page(e->buf),
-                                               true);
-                       break;
+               if (!q->skb) { /* first buffer */
+                       q->skb = napi_build_skb(e->buf, q->buf_size);
+                       if (!q->skb)
+                               goto free_frag;
+
+                       __skb_put(q->skb, len);
+                       skb_mark_for_recycle(q->skb);
+                       q->skb->dev = port->dev;
+                       q->skb->protocol = eth_type_trans(q->skb, port->dev);
+                       q->skb->ip_summed = CHECKSUM_UNNECESSARY;
+                       skb_record_rx_queue(q->skb, qid);
+               } else { /* scattered frame */
+                       struct skb_shared_info *shinfo = skb_shinfo(q->skb);
+                       int nr_frags = shinfo->nr_frags;
+
+                       if (nr_frags >= ARRAY_SIZE(shinfo->frags))
+                               goto free_frag;
+
+                       skb_add_rx_frag(q->skb, nr_frags, page,
+                                       e->buf - page_address(page), len,
+                                       q->buf_size);
                }
 
-               skb_reserve(skb, 2);
-               __skb_put(skb, len);
-               skb_mark_for_recycle(skb);
-               skb->dev = port->dev;
-               skb->protocol = eth_type_trans(skb, skb->dev);
-               skb->ip_summed = CHECKSUM_UNNECESSARY;
-               skb_record_rx_queue(skb, qid);
+               if (FIELD_GET(QDMA_DESC_MORE_MASK, desc_ctrl))
+                       continue;
 
                if (netdev_uses_dsa(port->dev)) {
                        /* PPE module requires untagged packets to work
@@ -672,22 +683,27 @@ static int airoha_qdma_rx_process(struct airoha_queue *q, int budget)
 
                        if (sptag < ARRAY_SIZE(port->dsa_meta) &&
                            port->dsa_meta[sptag])
-                               skb_dst_set_noref(skb,
+                               skb_dst_set_noref(q->skb,
                                                  &port->dsa_meta[sptag]->dst);
                }
 
                hash = FIELD_GET(AIROHA_RXD4_FOE_ENTRY, msg1);
                if (hash != AIROHA_RXD4_FOE_ENTRY)
-                       skb_set_hash(skb, jhash_1word(hash, 0),
+                       skb_set_hash(q->skb, jhash_1word(hash, 0),
                                     PKT_HASH_TYPE_L4);
 
                reason = FIELD_GET(AIROHA_RXD4_PPE_CPU_REASON, msg1);
                if (reason == PPE_CPU_REASON_HIT_UNBIND_RATE_REACHED)
                        airoha_ppe_check_skb(eth->ppe, hash);
 
-               napi_gro_receive(&q->napi, skb);
-
                done++;
+               napi_gro_receive(&q->napi, q->skb);
+               q->skb = NULL;
+               continue;
+free_frag:
+               page_pool_put_full_page(q->page_pool, page, true);
+               dev_kfree_skb(q->skb);
+               q->skb = NULL;
        }
        airoha_qdma_fill_rx_queue(q);
 
@@ -762,6 +778,7 @@ static int airoha_qdma_init_rx_queue(struct airoha_queue *q,
                        FIELD_PREP(RX_RING_THR_MASK, thr));
        airoha_qdma_rmw(qdma, REG_RX_DMA_IDX(qid), RX_RING_DMA_IDX_MASK,
                        FIELD_PREP(RX_RING_DMA_IDX_MASK, q->head));
+       airoha_qdma_set(qdma, REG_RX_SCATTER_CFG(qid), RX_RING_SG_EN_MASK);
 
        airoha_qdma_fill_rx_queue(q);
 
@@ -1161,7 +1178,6 @@ static int airoha_qdma_hw_init(struct airoha_qdma *qdma)
        }
 
        airoha_qdma_wr(qdma, REG_QDMA_GLOBAL_CFG,
-                      GLOBAL_CFG_RX_2B_OFFSET_MASK |
                       FIELD_PREP(GLOBAL_CFG_DMA_PREFERENCE_MASK, 3) |
                       GLOBAL_CFG_CPU_TXR_RR_MASK |
                       GLOBAL_CFG_PAYLOAD_BYTE_SWAP_MASK |

diff --git a/drivers/net/ethernet/airoha/airoha_eth.h b/drivers/net/ethernet/airoha/airoha_eth.h
index b7a3bd7a76b7be3125a2f244582e5bceab48bd47..dca96f1df67ee971e5442b0acfac211554accc89 100644 (file)
--- a/drivers/net/ethernet/airoha/airoha_eth.h
+++ b/drivers/net/ethernet/airoha/airoha_eth.h
@@ -176,6 +176,7 @@ struct airoha_queue {
 
        struct napi_struct napi;
        struct page_pool *page_pool;
+       struct sk_buff *skb;
 };
 
 struct airoha_tx_irq_queue {

diff --git a/drivers/net/ethernet/airoha/airoha_regs.h b/drivers/net/ethernet/airoha/airoha_regs.h
index 1aa06cdffe2320375e8710d58f2bbb056a330dfd..8146cde4e8ba370e79b9b1bd87bb66a2caf7649a 100644 (file)
--- a/drivers/net/ethernet/airoha/airoha_regs.h
+++ b/drivers/net/ethernet/airoha/airoha_regs.h
@@ -626,10 +626,15 @@
 #define REG_RX_DELAY_INT_IDX(_n)       \
        (((_n) < 16) ? 0x0210 + ((_n) << 5) : 0x0e10 + (((_n) - 16) << 5))
 
+#define REG_RX_SCATTER_CFG(_n) \
+       (((_n) < 16) ? 0x0214 + ((_n) << 5) : 0x0e14 + (((_n) - 16) << 5))
+
 #define RX_DELAY_INT_MASK              GENMASK(15, 0)
 
 #define RX_RING_DMA_IDX_MASK           GENMASK(15, 0)
 
+#define RX_RING_SG_EN_MASK             BIT(0)
+
 #define REG_INGRESS_TRTCM_CFG          0x0070
 #define INGRESS_TRTCM_EN_MASK          BIT(31)
 #define INGRESS_TRTCM_MODE_MASK                BIT(30)