NET/KS8695: add support NAPI for Rx

Add support NAPI Rx API for KS8695NET driver.

v2, change the Rx function to NAPI.

in <KS8695X Integrated Multi-port Gateway Solution Register Description
 v1.0>:

Interrupt Enable Register (offset 0xE204)
Bit29 : WAN MAC Receive Interrupt Enable
Bit16 : LAN MAC Receive Interrupt Enable

Interrupt Status Register (Offset 0xF208)
Bit29: WAN MAC Receive Status
Bit16: LAN MAC Receive Status

see arch/arm/mach-ks8695/devices.c:
ks8695_wan_resources[] and ks8695_lan_resources[]
have IORESOURCE_IRQ , it have define the RX irq,
for wan, irq = 29; for lan ,irq = 16.
so we can do this read the interrupt status:

unsigned long mask_bit = 1 << ksp->rx_irq;
status = readl(KS8695_IRQ_VA + KS8695_INTST);

Signed-off-by: Figo.zhang <figo1802@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 78 insertions, 25 deletions

diff --git a/drivers/net/arm/ks8695net.c b/drivers/net/arm/ks8695net.c
index 2a7b7745cc55..ed0b0f3b7122 100644
--- a/drivers/net/arm/ks8695net.c
+++ b/drivers/net/arm/ks8695net.c
@@ -35,12 +35,15 @@
 
 #include <mach/regs-switch.h>
 #include <mach/regs-misc.h>
+#include <asm/mach/irq.h>
+#include <mach/regs-irq.h>
 
 #include "ks8695net.h"
 
 #define MODULENAME      "ks8695_ether"
 #define MODULEVERSION   "1.01"
 
+
 /*
  * Transmit and device reset timeout, default 5 seconds.
  */
@@ -152,6 +155,8 @@ struct ks8695_priv {
         enum ks8695_dtype dtype;
         void __iomem *io_regs;
 
+        struct napi_struct      napi;
+
         const char *rx_irq_name, *tx_irq_name, *link_irq_name;
         int rx_irq, tx_irq, link_irq;
 
@@ -172,6 +177,7 @@ struct ks8695_priv {
         dma_addr_t rx_ring_dma;
         struct ks8695_skbuff rx_buffers[MAX_RX_DESC];
         int next_rx_desc_read;
+        spinlock_t rx_lock;
 
         int msg_enable;
 };
@@ -396,25 +402,53 @@ ks8695_tx_irq(int irq, void *dev_id)
  *      @irq: The IRQ which went off (ignored)
  *      @dev_id: The net_device for the interrupt
  *
- *      Process the RX ring, passing any received packets up to the
- *      host.  If we received anything other than errors, we then
- *      refill the ring.
+ *      Use NAPI to receive packets.
  */
+
 static irqreturn_t
 ks8695_rx_irq(int irq, void *dev_id)
 {
         struct net_device *ndev = (struct net_device *)dev_id;
         struct ks8695_priv *ksp = netdev_priv(ndev);
+        unsigned long status;
+
+        unsigned long mask_bit = 1 << ksp->rx_irq;
+
+        spin_lock(&ksp->rx_lock);
+
+        status = readl(KS8695_IRQ_VA + KS8695_INTST);
+
+        /*clean rx status bit*/
+        writel(status | mask_bit , KS8695_IRQ_VA + KS8695_INTST);
+
+        if (status & mask_bit) {
+                if (napi_schedule_prep(&ksp->napi)) {
+                        /*disable rx interrupt*/
+                        status &= ~mask_bit;
+                        writel(status , KS8695_IRQ_VA + KS8695_INTEN);
+                        __napi_schedule(&ksp->napi);
+                }
+        }
+
+        spin_unlock(&ksp->rx_lock);
+        return IRQ_HANDLED;
+}
+
+static int ks8695_rx(struct net_device *ndev, int budget)
+{
+        struct ks8695_priv *ksp = netdev_priv(ndev);
         struct sk_buff *skb;
         int buff_n;
         u32 flags;
         int pktlen;
         int last_rx_processed = -1;
+        int received = 0;
 
         buff_n = ksp->next_rx_desc_read;
-        do {
-                if (ksp->rx_buffers[buff_n].skb &&
-                    !(ksp->rx_ring[buff_n].status & cpu_to_le32(RDES_OWN))) {
+        while (received < budget
+                        && ksp->rx_buffers[buff_n].skb
+                        && (!(ksp->rx_ring[buff_n].status &
+                                        cpu_to_le32(RDES_OWN)))) {
                         rmb();
                         flags = le32_to_cpu(ksp->rx_ring[buff_n].status);
                         /* Found an SKB which we own, this means we
@@ -464,7 +498,7 @@ ks8695_rx_irq(int irq, void *dev_id)
                         /* Relinquish the SKB to the network layer */
                         skb_put(skb, pktlen);
                         skb->protocol = eth_type_trans(skb, ndev);
-                        netif_rx(skb);
+                        netif_receive_skb(skb);
 
                         /* Record stats */
                         ndev->stats.rx_packets++;
@@ -478,29 +512,44 @@ rx_failure:
                         /* Give the ring entry back to the hardware */
                         ksp->rx_ring[buff_n].status = cpu_to_le32(RDES_OWN);
 rx_finished:
+                        received++;
                         /* And note this as processed so we can start
                          * from here next time
                          */
                         last_rx_processed = buff_n;
-                } else {
-                        /* Ran out of things to process, stop now */
-                        break;
-                }
-                buff_n = (buff_n + 1) & MAX_RX_DESC_MASK;
-        } while (buff_n != ksp->next_rx_desc_read);
-
-        /* And note which RX descriptor we last did anything with */
-        if (likely(last_rx_processed != -1))
-                ksp->next_rx_desc_read =
-                        (last_rx_processed + 1) & MAX_RX_DESC_MASK;
-
-        /* And refill the buffers */
-        ks8695_refill_rxbuffers(ksp);
-
-        /* Kick the RX DMA engine, in case it became suspended */
-        ks8695_writereg(ksp, KS8695_DRSC, 0);
+                        buff_n = (buff_n + 1) & MAX_RX_DESC_MASK;
+                        /*And note which RX descriptor we last did */
+                        if (likely(last_rx_processed != -1))
+                                ksp->next_rx_desc_read =
+                                        (last_rx_processed + 1) &
+                                        MAX_RX_DESC_MASK;
+
+                        /* And refill the buffers */
+                        ks8695_refill_rxbuffers(ksp);
+        }
+        return received;
+}
 
-        return IRQ_HANDLED;
+static int ks8695_poll(struct napi_struct *napi, int budget)
+{
+        struct ks8695_priv *ksp = container_of(napi, struct ks8695_priv, napi);
+        struct net_device *dev = ksp->ndev;
+        unsigned long mask_bit = 1 << ksp->rx_irq;
+        unsigned long isr = readl(KS8695_IRQ_VA + KS8695_INTEN);
+
+        unsigned long  work_done ;
+
+        work_done = ks8695_rx(dev, budget);
+
+        if (work_done < budget) {
+                unsigned long flags;
+                spin_lock_irqsave(&ksp->rx_lock, flags);
+                /*enable rx interrupt*/
+                writel(isr | mask_bit, KS8695_IRQ_VA + KS8695_INTEN);
+                __napi_complete(napi);
+                spin_unlock_irqrestore(&ksp->rx_lock, flags);
+        }
+        return work_done;
 }
 
 /**
@@ -1472,6 +1521,8 @@ ks8695_probe(struct platform_device *pdev)
         SET_ETHTOOL_OPS(ndev, &ks8695_ethtool_ops);
         ndev->watchdog_timeo     = msecs_to_jiffies(watchdog);
 
+        netif_napi_add(ndev, &ksp->napi, ks8695_poll, 64);
+
         /* Retrieve the default MAC addr from the chip. */
         /* The bootloader should have left it in there for us. */
 
@@ -1505,6 +1556,7 @@ ks8695_probe(struct platform_device *pdev)
 
         /* And initialise the queue's lock */
         spin_lock_init(&ksp->txq_lock);
+        spin_lock_init(&ksp->rx_lock);
 
         /* Specify the RX DMA ring buffer */
         ksp->rx_ring = ksp->ring_base + TX_RING_DMA_SIZE;
@@ -1626,6 +1678,7 @@ ks8695_drv_remove(struct platform_device *pdev)
         struct ks8695_priv *ksp = netdev_priv(ndev);
 
         platform_set_drvdata(pdev, NULL);
+        netif_napi_del(&ksp->napi);
 
         unregister_netdev(ndev);
         ks8695_release_device(ksp);