fjes: NAPI polling function

This patch adds NAPI polling function and receive related work.

Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 214 insertions, 2 deletions

diff --git a/drivers/net/fjes/fjes_hw.c b/drivers/net/fjes/fjes_hw.c
index 487dbc6b7c43..3c96d06d15cf 100644
--- a/drivers/net/fjes/fjes_hw.c
+++ b/drivers/net/fjes/fjes_hw.c
@@ -825,6 +825,46 @@ bool fjes_hw_check_vlan_id(struct epbuf_handler *epbh, u16 vlan_id)
         return ret;
 }
 
+bool fjes_hw_epbuf_rx_is_empty(struct epbuf_handler *epbh)
+{
+        union ep_buffer_info *info = epbh->info;
+
+        if (info->v1i.count_max == 0)
+                return true;
+
+        return EP_RING_EMPTY(info->v1i.head, info->v1i.tail,
+                             info->v1i.count_max);
+}
+
+void *fjes_hw_epbuf_rx_curpkt_get_addr(struct epbuf_handler *epbh,
+                                       size_t *psize)
+{
+        union ep_buffer_info *info = epbh->info;
+        struct esmem_frame *ring_frame;
+        void *frame;
+
+        ring_frame = (struct esmem_frame *)&(epbh->ring[EP_RING_INDEX
+                                             (info->v1i.head,
+                                              info->v1i.count_max) *
+                                             info->v1i.frame_max]);
+
+        *psize = (size_t)ring_frame->frame_size;
+
+        frame = ring_frame->frame_data;
+
+        return frame;
+}
+
+void fjes_hw_epbuf_rx_curpkt_drop(struct epbuf_handler *epbh)
+{
+        union ep_buffer_info *info = epbh->info;
+
+        if (fjes_hw_epbuf_rx_is_empty(epbh))
+                return;
+
+        EP_RING_INDEX_INC(epbh->info->v1i.head, info->v1i.count_max);
+}
+
 int fjes_hw_epbuf_tx_pkt_send(struct epbuf_handler *epbh,
                               void *frame, size_t size)
 {
diff --git a/drivers/net/fjes/fjes_hw.h b/drivers/net/fjes/fjes_hw.h
index 07e122614a76..3511db2f7eb0 100644
--- a/drivers/net/fjes/fjes_hw.h
+++ b/drivers/net/fjes/fjes_hw.h
@@ -69,6 +69,8 @@ struct fjes_hw;
         ((_num) = EP_RING_INDEX((_num) + 1, (_max)))
 #define EP_RING_FULL(_head, _tail, _max)                                \
         (0 == EP_RING_INDEX(((_tail) - (_head)), (_max)))
+#define EP_RING_EMPTY(_head, _tail, _max) \
+        (1 == EP_RING_INDEX(((_tail) - (_head)), (_max)))
 
 #define FJES_MTU_TO_BUFFER_SIZE(mtu) \
         (ETH_HLEN + VLAN_HLEN + (mtu) + ETH_FCS_LEN)
@@ -320,6 +322,9 @@ int fjes_hw_epid_is_shared(struct fjes_device_shared_info *, int);
 bool fjes_hw_check_epbuf_version(struct epbuf_handler *, u32);
 bool fjes_hw_check_mtu(struct epbuf_handler *, u32);
 bool fjes_hw_check_vlan_id(struct epbuf_handler *, u16);
+bool fjes_hw_epbuf_rx_is_empty(struct epbuf_handler *);
+void *fjes_hw_epbuf_rx_curpkt_get_addr(struct epbuf_handler *, size_t *);
+void fjes_hw_epbuf_rx_curpkt_drop(struct epbuf_handler *);
 int fjes_hw_epbuf_tx_pkt_send(struct epbuf_handler *, void *, size_t);
 
 #endif /* FJES_HW_H_ */
diff --git a/drivers/net/fjes/fjes_main.c b/drivers/net/fjes/fjes_main.c
index ac1e07636662..61949625176c 100644
--- a/drivers/net/fjes/fjes_main.c
+++ b/drivers/net/fjes/fjes_main.c
@@ -66,6 +66,9 @@ static int fjes_remove(struct platform_device *);
 static int fjes_sw_init(struct fjes_adapter *);
 static void fjes_netdev_setup(struct net_device *);
 
+static void fjes_rx_irq(struct fjes_adapter *, int);
+static int fjes_poll(struct napi_struct *, int);
+
 static const struct acpi_device_id fjes_acpi_ids[] = {
         {"PNP0C02", 0},
         {"", 0},
@@ -235,6 +238,8 @@ static int fjes_open(struct net_device *netdev)
         hw->txrx_stop_req_bit = 0;
         hw->epstop_req_bit = 0;
 
+        napi_enable(&adapter->napi);
+
         fjes_hw_capture_interrupt_status(hw);
 
         result = fjes_request_irq(adapter);
@@ -250,6 +255,7 @@ static int fjes_open(struct net_device *netdev)
 
 err_req_irq:
         fjes_free_irq(adapter);
+        napi_disable(&adapter->napi);
 
 err_setup_res:
         fjes_free_resources(adapter);
@@ -268,6 +274,8 @@ static int fjes_close(struct net_device *netdev)
 
         fjes_hw_raise_epstop(hw);
 
+        napi_disable(&adapter->napi);
+
         for (epidx = 0; epidx < hw->max_epid; epidx++) {
                 if (epidx == hw->my_epid)
                         continue;
@@ -701,14 +709,167 @@ static irqreturn_t fjes_intr(int irq, void *data)
 
         icr = fjes_hw_capture_interrupt_status(hw);
 
-        if (icr & REG_IS_MASK_IS_ASSERT)
+        if (icr & REG_IS_MASK_IS_ASSERT) {
+                if (icr & REG_ICTL_MASK_RX_DATA)
+                        fjes_rx_irq(adapter, icr & REG_IS_MASK_EPID);
+
                 ret = IRQ_HANDLED;
-        else
+        } else {
                 ret = IRQ_NONE;
+        }
 
         return ret;
 }
 
+static int fjes_rxframe_search_exist(struct fjes_adapter *adapter,
+                                     int start_epid)
+{
+        struct fjes_hw *hw = &adapter->hw;
+        enum ep_partner_status pstatus;
+        int max_epid, cur_epid;
+        int i;
+
+        max_epid = hw->max_epid;
+        start_epid = (start_epid + 1 + max_epid) % max_epid;
+
+        for (i = 0; i < max_epid; i++) {
+                cur_epid = (start_epid + i) % max_epid;
+                if (cur_epid == hw->my_epid)
+                        continue;
+
+                pstatus = fjes_hw_get_partner_ep_status(hw, cur_epid);
+                if (pstatus == EP_PARTNER_SHARED) {
+                        if (!fjes_hw_epbuf_rx_is_empty(
+                                &hw->ep_shm_info[cur_epid].rx))
+                                return cur_epid;
+                }
+        }
+        return -1;
+}
+
+static void *fjes_rxframe_get(struct fjes_adapter *adapter, size_t *psize,
+                              int *cur_epid)
+{
+        void *frame;
+
+        *cur_epid = fjes_rxframe_search_exist(adapter, *cur_epid);
+        if (*cur_epid < 0)
+                return NULL;
+
+        frame =
+        fjes_hw_epbuf_rx_curpkt_get_addr(
+                &adapter->hw.ep_shm_info[*cur_epid].rx, psize);
+
+        return frame;
+}
+
+static void fjes_rxframe_release(struct fjes_adapter *adapter, int cur_epid)
+{
+        fjes_hw_epbuf_rx_curpkt_drop(&adapter->hw.ep_shm_info[cur_epid].rx);
+}
+
+static void fjes_rx_irq(struct fjes_adapter *adapter, int src_epid)
+{
+        struct fjes_hw *hw = &adapter->hw;
+
+        fjes_hw_set_irqmask(hw, REG_ICTL_MASK_RX_DATA, true);
+
+        adapter->unset_rx_last = true;
+        napi_schedule(&adapter->napi);
+}
+
+static int fjes_poll(struct napi_struct *napi, int budget)
+{
+        struct fjes_adapter *adapter =
+                        container_of(napi, struct fjes_adapter, napi);
+        struct net_device *netdev = napi->dev;
+        struct fjes_hw *hw = &adapter->hw;
+        struct sk_buff *skb;
+        int work_done = 0;
+        int cur_epid = 0;
+        int epidx;
+        size_t frame_len;
+        void *frame;
+
+        for (epidx = 0; epidx < hw->max_epid; epidx++) {
+                if (epidx == hw->my_epid)
+                        continue;
+
+                adapter->hw.ep_shm_info[epidx].tx.info->v1i.rx_status |=
+                        FJES_RX_POLL_WORK;
+        }
+
+        while (work_done < budget) {
+                prefetch(&adapter->hw);
+                frame = fjes_rxframe_get(adapter, &frame_len, &cur_epid);
+
+                if (frame) {
+                        skb = napi_alloc_skb(napi, frame_len);
+                        if (!skb) {
+                                adapter->stats64.rx_dropped += 1;
+                                hw->ep_shm_info[cur_epid].net_stats
+                                                         .rx_dropped += 1;
+                                adapter->stats64.rx_errors += 1;
+                                hw->ep_shm_info[cur_epid].net_stats
+                                                         .rx_errors += 1;
+                        } else {
+                                memcpy(skb_put(skb, frame_len),
+                                       frame, frame_len);
+                                skb->protocol = eth_type_trans(skb, netdev);
+                                skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+                                netif_receive_skb(skb);
+
+                                work_done++;
+
+                                adapter->stats64.rx_packets += 1;
+                                hw->ep_shm_info[cur_epid].net_stats
+                                                         .rx_packets += 1;
+                                adapter->stats64.rx_bytes += frame_len;
+                                hw->ep_shm_info[cur_epid].net_stats
+                                                         .rx_bytes += frame_len;
+
+                                if (is_multicast_ether_addr(
+                                        ((struct ethhdr *)frame)->h_dest)) {
+                                        adapter->stats64.multicast += 1;
+                                        hw->ep_shm_info[cur_epid].net_stats
+                                                                 .multicast += 1;
+                                }
+                        }
+
+                        fjes_rxframe_release(adapter, cur_epid);
+                        adapter->unset_rx_last = true;
+                } else {
+                        break;
+                }
+        }
+
+        if (work_done < budget) {
+                napi_complete(napi);
+
+                if (adapter->unset_rx_last) {
+                        adapter->rx_last_jiffies = jiffies;
+                        adapter->unset_rx_last = false;
+                }
+
+                if (((long)jiffies - (long)adapter->rx_last_jiffies) < 3) {
+                        napi_reschedule(napi);
+                } else {
+                        for (epidx = 0; epidx < hw->max_epid; epidx++) {
+                                if (epidx == hw->my_epid)
+                                        continue;
+                                adapter->hw.ep_shm_info[epidx]
+                                           .tx.info->v1i.rx_status &=
+                                                ~FJES_RX_POLL_WORK;
+                        }
+
+                        fjes_hw_set_irqmask(hw, REG_ICTL_MASK_RX_DATA, false);
+                }
+        }
+
+        return work_done;
+}
+
 /* fjes_probe - Device Initialization Routine */
 static int fjes_probe(struct platform_device *plat_dev)
 {
@@ -797,6 +958,8 @@ static int fjes_remove(struct platform_device *plat_dev)
 
         fjes_hw_exit(hw);
 
+        netif_napi_del(&adapter->napi);
+
         free_netdev(netdev);
 
         return 0;
@@ -804,6 +967,10 @@ static int fjes_remove(struct platform_device *plat_dev)
 
 static int fjes_sw_init(struct fjes_adapter *adapter)
 {
+        struct net_device *netdev = adapter->netdev;
+
+        netif_napi_add(netdev, &adapter->napi, fjes_poll, 64);
+
         return 0;
 }