NET:KS8695: add API for get rx interrupt bit

1. Add API Add k8695_get_rx_enable_bit() for get Rx interrupt
enable/status bit.
2. add some comment or document about some functions and variables.
3.  update driver version to "1.02"
4. add napi_enable() and napi_disable() in open/close file method.

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

diff --git a/drivers/net/arm/ks8695net.c b/drivers/net/arm/ks8695net.c
index ed0b0f3b7122c05514b350f9183414c1fa48dc38..0073d198715b8d376ca5276c5d2e4577ac3fe807 100644 (file)
--- a/drivers/net/arm/ks8695net.c
+++ b/drivers/net/arm/ks8695net.c
@@ -41,8 +41,7 @@
 #include "ks8695net.h"
 
 #define MODULENAME     "ks8695_ether"
-#define MODULEVERSION  "1.01"
-
+#define MODULEVERSION  "1.02"
 
 /*
  * Transmit and device reset timeout, default 5 seconds.
@@ -98,6 +97,9 @@ struct ks8695_skbuff {
 #define MAX_RX_DESC 16
 #define MAX_RX_DESC_MASK 0xf
 
+/*napi_weight have better more than rx DMA buffers*/
+#define NAPI_WEIGHT   64
+
 #define MAX_RXBUF_SIZE 0x700
 
 #define TX_RING_DMA_SIZE (sizeof(struct tx_ring_desc) * MAX_TX_DESC)
@@ -123,6 +125,7 @@ enum ks8695_dtype {
  *     @dev: The platform device object for this interface
  *     @dtype: The type of this device
  *     @io_regs: The ioremapped registers for this interface
+ *      @napi : Add support NAPI for Rx
  *     @rx_irq_name: The textual name of the RX IRQ from the platform data
  *     @tx_irq_name: The textual name of the TX IRQ from the platform data
  *     @link_irq_name: The textual name of the link IRQ from the
@@ -146,6 +149,7 @@ enum ks8695_dtype {
  *     @rx_ring_dma: The DMA mapped equivalent of rx_ring
  *     @rx_buffers: The sk_buff mappings for the RX ring
  *     @next_rx_desc_read: The next RX descriptor to read from on IRQ
+ *      @rx_lock: A lock to protect Rx irq function
  *     @msg_enable: The flags for which messages to emit
  */
 struct ks8695_priv {
@@ -397,12 +401,31 @@ ks8695_tx_irq(int irq, void *dev_id)
        return IRQ_HANDLED;
 }
 
+/**
+ *     ks8695_get_rx_enable_bit - Get rx interrupt enable/status bit
+ *     @ksp: Private data for the KS8695 Ethernet
+ *
+ *    For KS8695 document:
+ *    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
+ *    So, this Rx interrrupt enable/status bit number is equal
+ *    as Rx IRQ number.
+ */
+static inline u32 ks8695_get_rx_enable_bit(struct ks8695_priv *ksp)
+{
+       return ksp->rx_irq;
+}
+
 /**
  *     ks8695_rx_irq - Receive IRQ handler
  *     @irq: The IRQ which went off (ignored)
  *     @dev_id: The net_device for the interrupt
  *
- *     Use NAPI to receive packets.
+ *     Inform NAPI that packet reception needs to be scheduled
  */
 
 static irqreturn_t
@@ -412,7 +435,7 @@ ks8695_rx_irq(int irq, void *dev_id)
        struct ks8695_priv *ksp = netdev_priv(ndev);
        unsigned long status;
 
-       unsigned long mask_bit = 1 << ksp->rx_irq;
+       unsigned long mask_bit = 1 << ks8695_get_rx_enable_bit(ksp);
 
        spin_lock(&ksp->rx_lock);
 
@@ -434,9 +457,15 @@ ks8695_rx_irq(int irq, void *dev_id)
        return IRQ_HANDLED;
 }
 
-static int ks8695_rx(struct net_device *ndev, int budget)
+/**
+ *     ks8695_rx - Receive packets  called by NAPI poll method
+ *     @ksp: Private data for the KS8695 Ethernet
+ *     @budget: The max packets would be receive
+ */
+
+static int ks8695_rx(struct ks8695_priv *ksp, int budget)
 {
-       struct ks8695_priv *ksp = netdev_priv(ndev);
+       struct net_device *ndev = ksp->ndev;
        struct sk_buff *skb;
        int buff_n;
        u32 flags;
@@ -526,20 +555,32 @@ rx_finished:
 
                        /* And refill the buffers */
                        ks8695_refill_rxbuffers(ksp);
+
+                       /* Kick the RX DMA engine, in case it became
+                        *  suspended */
+                       ks8695_writereg(ksp, KS8695_DRSC, 0);
        }
        return received;
 }
 
+
+/**
+ *     ks8695_poll - Receive packet by NAPI poll method
+ *     @ksp: Private data for the KS8695 Ethernet
+ *     @budget: The remaining number packets for network subsystem
+ *
+ *     Invoked by the network core when it requests for new
+ *     packets from the driver
+ */
 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;
 
-       unsigned long  work_done ;
+       unsigned long isr = readl(KS8695_IRQ_VA + KS8695_INTEN);
+       unsigned long mask_bit = 1 << ks8695_get_rx_enable_bit(ksp);
 
-       work_done = ks8695_rx(dev, budget);
+       work_done = ks8695_rx(ksp, budget);
 
        if (work_done < budget) {
                unsigned long flags;
@@ -1302,6 +1343,7 @@ ks8695_stop(struct net_device *ndev)
        struct ks8695_priv *ksp = netdev_priv(ndev);
 
        netif_stop_queue(ndev);
+       napi_disable(&ksp->napi);
        netif_carrier_off(ndev);
 
        ks8695_shutdown(ksp);
@@ -1336,6 +1378,7 @@ ks8695_open(struct net_device *ndev)
                return ret;
        }
 
+       napi_enable(&ksp->napi);
        netif_start_queue(ndev);
 
        return 0;
@@ -1521,7 +1564,7 @@ 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);
+       netif_napi_add(ndev, &ksp->napi, ks8695_poll, NAPI_WEIGHT);
 
        /* Retrieve the default MAC addr from the chip. */
        /* The bootloader should have left it in there for us. */