realtek: dsa/eth: adapt receive path

Improve the DSA receive tagging. For this convert the receive path
to METADATA_HW_PORT_MUX. This way no skb data mangling is needed.
See e.g. airoha_eth.c or mtk_eth_soc.c.

Link: https://github.com/openwrt/openwrt/pull/23948
Signed-off-by: Markus Stockhausen <markus.stockhausen@gmx.de>

diff --git a/target/linux/realtek/files-6.18/drivers/net/ethernet/rtl838x_eth.c b/target/linux/realtek/files-6.18/drivers/net/ethernet/rtl838x_eth.c
index b9cb572492324326f702dae58e19fe99d31ac2c4..0dfd36a82f4089ad670cc0df11b7770f928afcc0 100644 (file)
--- a/target/linux/realtek/files-6.18/drivers/net/ethernet/rtl838x_eth.c
+++ b/target/linux/realtek/files-6.18/drivers/net/ethernet/rtl838x_eth.c
@@ -21,6 +21,7 @@
 #include <linux/pkt_sched.h>
 #include <linux/regmap.h>
 #include <net/dsa.h>
+#include <net/dst_metadata.h>
 #include <net/page_pool/helpers.h>
 #include <net/switchdev.h>
 
@@ -113,6 +114,7 @@ struct rteth_ctrl {
        struct phylink_config phylink_config;
        const struct rteth_config *r;
        u32 lastEvent;
+       struct metadata_dst *dsa_meta[RTETH_931X_CPU_PORT];
        /* receive handling */
        dma_addr_t              rx_data_dma;
        spinlock_t              rx_lock;
@@ -1097,11 +1099,10 @@ static int rteth_start_xmit(struct sk_buff *skb, struct net_device *dev)
 
 static int rteth_hw_receive(struct net_device *dev, int ring, int budget)
 {
-       int slot, len, work_done = 0, rx_packets = 0, rx_bytes = 0;
+       int slot, work_done = 0, rx_packets = 0, rx_bytes = 0;
        struct rteth_ctrl *ctrl = netdev_priv(dev);
-       unsigned int new_offset, old_offset;
+       unsigned int len, new_offset, old_offset;
        struct page *old_page, *new_page;
-       bool dsa = netdev_uses_dsa(dev);
        struct rteth_packet *packet;
        dma_addr_t packet_dma;
        struct sk_buff *skb;
@@ -1116,9 +1117,9 @@ static int rteth_hw_receive(struct net_device *dev, int ring, int budget)
                        break;
 
                packet = &ctrl->rx_data[ring].packet[slot];
-               len = packet->len;
+               len = packet->len - ETH_FCS_LEN;
 
-               if (unlikely(len < ETH_FCS_LEN || len > RING_BUFFER)) {
+               if (unlikely(len > RING_BUFFER)) {
                        netdev_err(dev, "invalid packet with %d bytes received\n", len);
                        dev->stats.rx_errors++;
                        goto recycle;
@@ -1138,9 +1139,6 @@ static int rteth_hw_receive(struct net_device *dev, int ring, int budget)
                packet->page_offset = new_offset;
                packet->dma = page_pool_get_dma_addr(new_page) + new_offset + RTETH_SKB_HEADROOM;
 
-               if (!dsa)
-                       len -= ETH_FCS_LEN;
-
                page_pool_dma_sync_for_cpu(ctrl->rx_qs[ring].page_pool, old_page,
                                           old_offset + RTETH_SKB_HEADROOM, len);
 
@@ -1156,13 +1154,11 @@ static int rteth_hw_receive(struct net_device *dev, int ring, int budget)
                skb_put(skb, len);
 
                ctrl->r->decode_tag(packet, &tag);
-               if (dsa) {
-                       skb->data[len - 4] = 0x80;
-                       skb->data[len - 3] = tag.port;
-                       skb->data[len - 2] = 0x10;
-                       skb->data[len - 1] = 0x00;
+               if (netdev_uses_dsa(dev)) {
+                       if (tag.port < ctrl->r->cpu_port)
+                               skb_dst_set_noref(skb, &ctrl->dsa_meta[tag.port]->dst);
                        if (tag.l2_offloaded)
-                               skb->data[len - 3] |= 0x40;
+                               skb->offload_fwd_mark = 1;
                }
 
                skb->protocol = eth_type_trans(skb, dev);
@@ -1606,6 +1602,32 @@ static const struct ethtool_ops rteth_ethtool_ops = {
        .set_link_ksettings = rteth_set_link_ksettings,
 };
 
+static int rteth_metadata_dst_alloc(struct rteth_ctrl *ctrl)
+{
+       struct metadata_dst *md_dst;
+
+       for (int i = 0; i < ARRAY_SIZE(ctrl->dsa_meta); i++) {
+               md_dst = metadata_dst_alloc(0, METADATA_HW_PORT_MUX, GFP_KERNEL);
+               if (!md_dst)
+                       return -ENOMEM;
+
+               md_dst->u.port_info.port_id = i;
+               ctrl->dsa_meta[i] = md_dst;
+       }
+
+       return 0;
+}
+
+static void rteth_metadata_dst_free(struct rteth_ctrl *ctrl)
+{
+       for (int i = 0; i < ARRAY_SIZE(ctrl->dsa_meta); i++) {
+               if (!ctrl->dsa_meta[i])
+                       continue;
+
+               metadata_dst_free(ctrl->dsa_meta[i]);
+       }
+}
+
 static int rteth_probe(struct platform_device *pdev)
 {
        struct page_pool_params pp_params = {
@@ -1762,6 +1784,10 @@ static int rteth_probe(struct platform_device *pdev)
                }
        }
 
+       err = rteth_metadata_dst_alloc(ctrl);
+       if (err)
+               goto cleanup;
+
        err = register_netdev(dev);
        if (err)
                goto cleanup;
@@ -1769,6 +1795,7 @@ static int rteth_probe(struct platform_device *pdev)
        return 0;
 
 cleanup:
+       rteth_metadata_dst_free(ctrl);
        if (ctrl->phylink)
                phylink_destroy(ctrl->phylink);
        for (int i = 0; i < RTETH_RX_RINGS; i++) {
@@ -1787,6 +1814,7 @@ static void rteth_remove(struct platform_device *pdev)
 
        pr_info("Removing platform driver for rtl838x-eth\n");
        unregister_netdev(dev);
+       rteth_metadata_dst_free(ctrl);
 
        if (ctrl->phylink)
                phylink_destroy(ctrl->phylink);

diff --git a/target/linux/realtek/files-6.18/net/dsa/tag_rtl_otto.c b/target/linux/realtek/files-6.18/net/dsa/tag_rtl_otto.c
index 2048d5addbef32ade903cd80b1b1bd594387a16c..ecbf67b42ae15c113a9540b3c6eaf0a6c5d8c248 100644 (file)
--- a/target/linux/realtek/files-6.18/net/dsa/tag_rtl_otto.c
+++ b/target/linux/realtek/files-6.18/net/dsa/tag_rtl_otto.c
@@ -26,29 +26,8 @@ static struct sk_buff *rtl_otto_xmit(struct sk_buff *skb, struct net_device *dev
 
 static struct sk_buff *rtl_otto_rcv(struct sk_buff *skb, struct net_device *dev)
 {
-       u8 *trailer;
-       int source_port;
-
-       if (skb_linearize(skb))
-               return NULL;
-
-       trailer = skb_tail_pointer(skb) - 4;
-
-       if (trailer[0] != 0x80 || (trailer[1] & 0x80) != 0x00 ||
-           (trailer[2] & 0xef) != 0x00 || trailer[3] != 0x00)
-               return NULL;
-
-       if (trailer[1] & 0x40)
-               skb->offload_fwd_mark = 1;
-
-       source_port = trailer[1] & 0x3f;
-
-       skb->dev = dsa_conduit_find_user(dev, 0, source_port);
-       if (!skb->dev)
-               return NULL;
-
-       if (pskb_trim_rcsum(skb, skb->len - 4))
-               return NULL;
+       /* RX path uses METADATA_HW_PORT_MUX. This function just makes netdev_uses_dsa() happy. */
+       netdev_err(dev, "ethernet driver did not set METADATA\n");
 
        return skb;
 }