net-next: mediatek: add support for IRQ grouping

The ethernet core has 3 IRQs. Using the IRQ grouping registers we are able
to separate TX and RX IRQs, which allows us to service them on separate
cores. This patch splits the IRQ handler into 2 separate functions, one for
TX and another for RX. The TX housekeeping is split out into its own NAPI
handler.

Signed-off-by: John Crispin <john@phrozen.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
index 698caba..7056a37 100644 (file)
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
@@ -893,17 +893,17 @@ release_desc:
        return done;
 }
 
-static int mtk_poll_tx(struct mtk_eth *eth, int budget, bool *tx_again)
+static int mtk_poll_tx(struct mtk_eth *eth, int budget)
 {
        struct mtk_tx_ring *ring = &eth->tx_ring;
        struct mtk_tx_dma *desc;
        struct sk_buff *skb;
        struct mtk_tx_buf *tx_buf;
-       int total = 0, done[MTK_MAX_DEVS];
+       unsigned int done[MTK_MAX_DEVS];
        unsigned int bytes[MTK_MAX_DEVS];
        u32 cpu, dma;
        static int condition;
-       int i;
+       int total = 0, i;
 
        memset(done, 0, sizeof(done));
        memset(bytes, 0, sizeof(bytes));
@@ -954,15 +954,6 @@ static int mtk_poll_tx(struct mtk_eth *eth, int budget, bool *tx_again)
                total += done[i];
        }
 
-       /* read hw index again make sure no new tx packet */
-       if (cpu != dma || cpu != mtk_r32(eth, MTK_QTX_DRX_PTR))
-               *tx_again = true;
-       else
-               mtk_w32(eth, MTK_TX_DONE_INT, MTK_QMTK_INT_STATUS);
-
-       if (!total)
-               return 0;
-
        if (mtk_queue_stopped(eth) &&
            (atomic_read(&ring->free_count) > ring->thresh))
                mtk_wake_queue(eth);
@@ -970,47 +961,75 @@ static int mtk_poll_tx(struct mtk_eth *eth, int budget, bool *tx_again)
        return total;
 }
 
-static int mtk_poll(struct napi_struct *napi, int budget)
+static void mtk_handle_status_irq(struct mtk_eth *eth)
 {
-       struct mtk_eth *eth = container_of(napi, struct mtk_eth, rx_napi);
-       u32 status, status2, mask;
-       int tx_done, rx_done;
-       bool tx_again = false;
-
-       status = mtk_r32(eth, MTK_QMTK_INT_STATUS);
-       status2 = mtk_r32(eth, MTK_INT_STATUS2);
-       tx_done = 0;
-       rx_done = 0;
-       tx_again = 0;
-
-       if (status & MTK_TX_DONE_INT)
-               tx_done = mtk_poll_tx(eth, budget, &tx_again);
-
-       if (status & MTK_RX_DONE_INT)
-               rx_done = mtk_poll_rx(napi, budget, eth);
+       u32 status2 = mtk_r32(eth, MTK_INT_STATUS2);
 
        if (unlikely(status2 & (MTK_GDM1_AF | MTK_GDM2_AF))) {
                mtk_stats_update(eth);
                mtk_w32(eth, (MTK_GDM1_AF | MTK_GDM2_AF),
                        MTK_INT_STATUS2);
        }
+}
+
+static int mtk_napi_tx(struct napi_struct *napi, int budget)
+{
+       struct mtk_eth *eth = container_of(napi, struct mtk_eth, tx_napi);
+       u32 status, mask;
+       int tx_done = 0;
+
+       mtk_handle_status_irq(eth);
+       mtk_w32(eth, MTK_TX_DONE_INT, MTK_QMTK_INT_STATUS);
+       tx_done = mtk_poll_tx(eth, budget);
+
+       if (unlikely(netif_msg_intr(eth))) {
+               status = mtk_r32(eth, MTK_QMTK_INT_STATUS);
+               mask = mtk_r32(eth, MTK_QDMA_INT_MASK);
+               dev_info(eth->dev,
+                        "done tx %d, intr 0x%08x/0x%x\n",
+                        tx_done, status, mask);
+       }
+
+       if (tx_done == budget)
+               return budget;
+
+       status = mtk_r32(eth, MTK_QMTK_INT_STATUS);
+       if (status & MTK_TX_DONE_INT)
+               return budget;
+
+       napi_complete(napi);
+       mtk_irq_enable(eth, MTK_TX_DONE_INT);
+
+       return tx_done;
+}
+
+static int mtk_napi_rx(struct napi_struct *napi, int budget)
+{
+       struct mtk_eth *eth = container_of(napi, struct mtk_eth, rx_napi);
+       u32 status, mask;
+       int rx_done = 0;
+
+       mtk_handle_status_irq(eth);
+       mtk_w32(eth, MTK_RX_DONE_INT, MTK_QMTK_INT_STATUS);
+       rx_done = mtk_poll_rx(napi, budget, eth);
 
        if (unlikely(netif_msg_intr(eth))) {
+               status = mtk_r32(eth, MTK_QMTK_INT_STATUS);
                mask = mtk_r32(eth, MTK_QDMA_INT_MASK);
-               netdev_info(eth->netdev[0],
-                           "done tx %d, rx %d, intr 0x%08x/0x%x\n",
-                           tx_done, rx_done, status, mask);
+               dev_info(eth->dev,
+                        "done rx %d, intr 0x%08x/0x%x\n",
+                        rx_done, status, mask);
        }
 
-       if (tx_again || rx_done == budget)
+       if (rx_done == budget)
                return budget;
 
        status = mtk_r32(eth, MTK_QMTK_INT_STATUS);
-       if (status & (tx_intr | rx_intr))
+       if (status & MTK_RX_DONE_INT)
                return budget;
 
        napi_complete(napi);
-       mtk_irq_enable(eth, MTK_RX_DONE_INT | MTK_RX_DONE_INT);
+       mtk_irq_enable(eth, MTK_RX_DONE_INT);
 
        return rx_done;
 }
@@ -1246,22 +1265,26 @@ static void mtk_tx_timeout(struct net_device *dev)
        schedule_work(&eth->pending_work);
 }
 
-static irqreturn_t mtk_handle_irq(int irq, void *_eth)
+static irqreturn_t mtk_handle_irq_rx(int irq, void *_eth)
 {
        struct mtk_eth *eth = _eth;
-       u32 status;
 
-       status = mtk_r32(eth, MTK_QMTK_INT_STATUS);
-       if (unlikely(!status))
-               return IRQ_NONE;
+       if (likely(napi_schedule_prep(&eth->rx_napi))) {
+               __napi_schedule(&eth->rx_napi);
+               mtk_irq_disable(eth, MTK_RX_DONE_INT);
+       }
 
-       if (likely(status & (MTK_RX_DONE_INT | MTK_TX_DONE_INT))) {
-               if (likely(napi_schedule_prep(&eth->rx_napi)))
-                       __napi_schedule(&eth->rx_napi);
-       } else {
-               mtk_w32(eth, status, MTK_QMTK_INT_STATUS);
+       return IRQ_HANDLED;
+}
+
+static irqreturn_t mtk_handle_irq_tx(int irq, void *_eth)
+{
+       struct mtk_eth *eth = _eth;
+
+       if (likely(napi_schedule_prep(&eth->tx_napi))) {
+               __napi_schedule(&eth->tx_napi);
+               mtk_irq_disable(eth, MTK_TX_DONE_INT);
        }
-       mtk_irq_disable(eth, (MTK_RX_DONE_INT | MTK_TX_DONE_INT));
 
        return IRQ_HANDLED;
 }
@@ -1274,7 +1297,7 @@ static void mtk_poll_controller(struct net_device *dev)
        u32 int_mask = MTK_TX_DONE_INT | MTK_RX_DONE_INT;
 
        mtk_irq_disable(eth, int_mask);
-       mtk_handle_irq(dev->irq, dev);
+       mtk_handle_irq(dev->irq[0], dev);
        mtk_irq_enable(eth, int_mask);
 }
 #endif
@@ -1310,6 +1333,7 @@ static int mtk_open(struct net_device *dev)
                if (err)
                        return err;
 
+               napi_enable(&eth->tx_napi);
                napi_enable(&eth->rx_napi);
                mtk_irq_enable(eth, MTK_TX_DONE_INT | MTK_RX_DONE_INT);
        }
@@ -1358,6 +1382,7 @@ static int mtk_stop(struct net_device *dev)
                return 0;
 
        mtk_irq_disable(eth, MTK_TX_DONE_INT | MTK_RX_DONE_INT);
+       napi_disable(&eth->tx_napi);
        napi_disable(&eth->rx_napi);
 
        mtk_stop_dma(eth, MTK_QDMA_GLO_CFG);
@@ -1395,7 +1420,11 @@ static int __init mtk_hw_init(struct mtk_eth *eth)
        /* Enable RX VLan Offloading */
        mtk_w32(eth, 1, MTK_CDMP_EG_CTRL);
 
-       err = devm_request_irq(eth->dev, eth->irq, mtk_handle_irq, 0,
+       err = devm_request_irq(eth->dev, eth->irq[1], mtk_handle_irq_tx, 0,
+                              dev_name(eth->dev), eth);
+       if (err)
+               return err;
+       err = devm_request_irq(eth->dev, eth->irq[2], mtk_handle_irq_rx, 0,
                               dev_name(eth->dev), eth);
        if (err)
                return err;
@@ -1411,7 +1440,11 @@ static int __init mtk_hw_init(struct mtk_eth *eth)
        mtk_w32(eth, 0, MTK_RST_GL);
 
        /* FE int grouping */
-       mtk_w32(eth, 0, MTK_FE_INT_GRP);
+       mtk_w32(eth, MTK_TX_DONE_INT, MTK_PDMA_INT_GRP1);
+       mtk_w32(eth, MTK_RX_DONE_INT, MTK_PDMA_INT_GRP2);
+       mtk_w32(eth, MTK_TX_DONE_INT, MTK_QDMA_INT_GRP1);
+       mtk_w32(eth, MTK_RX_DONE_INT, MTK_QDMA_INT_GRP2);
+       mtk_w32(eth, 0x21021000, MTK_FE_INT_GRP);
 
        for (i = 0; i < 2; i++) {
                u32 val = mtk_r32(eth, MTK_GDMA_FWD_CFG(i));
@@ -1459,7 +1492,9 @@ static void mtk_uninit(struct net_device *dev)
        phy_disconnect(mac->phy_dev);
        mtk_mdio_cleanup(eth);
        mtk_irq_disable(eth, ~0);
-       free_irq(dev->irq, dev);
+       free_irq(eth->irq[0], dev);
+       free_irq(eth->irq[1], dev);
+       free_irq(eth->irq[2], dev);
 }
 
 static int mtk_do_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
@@ -1733,10 +1768,10 @@ static int mtk_add_mac(struct mtk_eth *eth, struct device_node *np)
                dev_err(eth->dev, "error bringing up device\n");
                goto free_netdev;
        }
-       eth->netdev[id]->irq = eth->irq;
+       eth->netdev[id]->irq = eth->irq[0];
        netif_info(eth, probe, eth->netdev[id],
                   "mediatek frame engine at 0x%08lx, irq %d\n",
-                  eth->netdev[id]->base_addr, eth->netdev[id]->irq);
+                  eth->netdev[id]->base_addr, eth->irq[0]);
 
        return 0;
 
@@ -1753,6 +1788,7 @@ static int mtk_probe(struct platform_device *pdev)
        struct mtk_soc_data *soc;
        struct mtk_eth *eth;
        int err;
+       int i;
 
        match = of_match_device(of_mtk_match, &pdev->dev);
        soc = (struct mtk_soc_data *)match->data;
@@ -1788,10 +1824,12 @@ static int mtk_probe(struct platform_device *pdev)
                return PTR_ERR(eth->rstc);
        }
 
-       eth->irq = platform_get_irq(pdev, 0);
-       if (eth->irq < 0) {
-               dev_err(&pdev->dev, "no IRQ resource found\n");
-               return -ENXIO;
+       for (i = 0; i < 3; i++) {
+               eth->irq[i] = platform_get_irq(pdev, i);
+               if (eth->irq[i] < 0) {
+                       dev_err(&pdev->dev, "no IRQ%d resource found\n", i);
+                       return -ENXIO;
+               }
        }
 
        eth->clk_ethif = devm_clk_get(&pdev->dev, "ethif");
@@ -1832,7 +1870,9 @@ static int mtk_probe(struct platform_device *pdev)
         * for NAPI to work
         */
        init_dummy_netdev(&eth->dummy_dev);
-       netif_napi_add(&eth->dummy_dev, &eth->rx_napi, mtk_poll,
+       netif_napi_add(&eth->dummy_dev, &eth->tx_napi, mtk_napi_tx,
+                      MTK_NAPI_WEIGHT);
+       netif_napi_add(&eth->dummy_dev, &eth->rx_napi, mtk_napi_rx,
                       MTK_NAPI_WEIGHT);
 
        platform_set_drvdata(pdev, eth);
@@ -1853,6 +1893,7 @@ static int mtk_remove(struct platform_device *pdev)
        clk_disable_unprepare(eth->clk_gp1);
        clk_disable_unprepare(eth->clk_gp2);
 
+       netif_napi_del(&eth->tx_napi);
        netif_napi_del(&eth->rx_napi);
        mtk_cleanup(eth);
        platform_set_drvdata(pdev, NULL);

diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.h b/drivers/net/ethernet/mediatek/mtk_eth_soc.h
index 3159d2a..f82e3ac 100644 (file)
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.h
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.h
@@ -68,6 +68,10 @@
 /* Unicast Filter MAC Address Register - High */
 #define MTK_GDMA_MAC_ADRH(x)   (0x50C + (x * 0x1000))
 
+/* PDMA Interrupt grouping registers */
+#define MTK_PDMA_INT_GRP1      0xa50
+#define MTK_PDMA_INT_GRP2      0xa54
+
 /* QDMA TX Queue Configuration Registers */
 #define MTK_QTX_CFG(x)         (0x1800 + (x * 0x10))
 #define QDMA_RES_THRES         4
@@ -125,6 +129,11 @@
 #define MTK_TX_DONE_INT                (MTK_TX_DONE_INT0 | MTK_TX_DONE_INT1 | \
                                 MTK_TX_DONE_INT2 | MTK_TX_DONE_INT3)
 
+/* QDMA Interrupt grouping registers */
+#define MTK_QDMA_INT_GRP1      0x1a20
+#define MTK_QDMA_INT_GRP2      0x1a24
+#define MTK_RLS_DONE_INT       BIT(0)
+
 /* QDMA Interrupt Status Register */
 #define MTK_QDMA_INT_MASK      0x1A1C
 
@@ -356,7 +365,8 @@ struct mtk_rx_ring {
  * @dma_refcnt:                track how many netdevs are using the DMA engine
  * @tx_ring:           Pointer to the memore holding info about the TX ring
  * @rx_ring:           Pointer to the memore holding info about the RX ring
- * @rx_napi:           The NAPI struct
+ * @tx_napi:           The TX NAPI struct
+ * @rx_napi:           The RX NAPI struct
  * @scratch_ring:      Newer SoCs need memory for a second HW managed TX ring
  * @phy_scratch_ring:  physical address of scratch_ring
  * @scratch_head:      The scratch memory that scratch_ring points to.
@@ -377,7 +387,7 @@ struct mtk_eth {
        struct net_device               dummy_dev;
        struct net_device               *netdev[MTK_MAX_DEVS];
        struct mtk_mac                  *mac[MTK_MAX_DEVS];
-       int                             irq;
+       int                             irq[3];
        u32                             msg_enable;
        unsigned long                   sysclk;
        struct regmap                   *ethsys;
@@ -385,6 +395,7 @@ struct mtk_eth {
        atomic_t                        dma_refcnt;
        struct mtk_tx_ring              tx_ring;
        struct mtk_rx_ring              rx_ring;
+       struct napi_struct              tx_napi;
        struct napi_struct              rx_napi;
        struct mtk_tx_dma               *scratch_ring;
        dma_addr_t                      phy_scratch_ring;