mpc85xx: revert the napi polling code to the one from an older kernel version to...

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@38409 3c298f89-4303-0410-b956-a3cf2f4a3e73

diff --git a/target/linux/mpc85xx/patches-3.10/200-gianfar_napi_poll_revert.patch b/target/linux/mpc85xx/patches-3.10/200-gianfar_napi_poll_revert.patch
new file mode 100644 (file)
index 0000000..9f2b727
--- /dev/null
+++ b/target/linux/mpc85xx/patches-3.10/200-gianfar_napi_poll_revert.patch
@@ -0,0 +1,162 @@
+--- a/drivers/net/ethernet/freescale/gianfar.c
++++ b/drivers/net/ethernet/freescale/gianfar.c
+@@ -132,7 +132,7 @@ static int gfar_poll(struct napi_struct 
+ static void gfar_netpoll(struct net_device *dev);
+ #endif
+ int gfar_clean_rx_ring(struct gfar_priv_rx_q *rx_queue, int rx_work_limit);
+-static void gfar_clean_tx_ring(struct gfar_priv_tx_q *tx_queue);
++static int gfar_clean_tx_ring(struct gfar_priv_tx_q *tx_queue);
+ static void gfar_process_frame(struct net_device *dev, struct sk_buff *skb,
+                              int amount_pull, struct napi_struct *napi);
+ void gfar_halt(struct net_device *dev);
+@@ -2475,7 +2475,7 @@ static void gfar_align_skb(struct sk_buf
+ }
+ 
+ /* Interrupt Handler for Transmit complete */
+-static void gfar_clean_tx_ring(struct gfar_priv_tx_q *tx_queue)
++static int gfar_clean_tx_ring(struct gfar_priv_tx_q *tx_queue)
+ {
+       struct net_device *dev = tx_queue->dev;
+       struct netdev_queue *txq;
+@@ -2575,6 +2575,8 @@ static void gfar_clean_tx_ring(struct gf
+       tx_queue->dirty_tx = bdp;
+ 
+       netdev_tx_completed_queue(txq, howmany, bytes_sent);
++
++      return howmany;
+ }
+ 
+ static void gfar_schedule_cleanup(struct gfar_priv_grp *gfargrp)
+@@ -2833,82 +2835,62 @@ static int gfar_poll(struct napi_struct 
+       struct gfar __iomem *regs = gfargrp->regs;
+       struct gfar_priv_tx_q *tx_queue = NULL;
+       struct gfar_priv_rx_q *rx_queue = NULL;
+-      int work_done = 0, work_done_per_q = 0;
+-      int i, budget_per_q = 0;
+-      int has_tx_work;
+-      unsigned long rstat_rxf;
+-      int num_act_queues;
++      int rx_cleaned = 0, budget_per_queue = 0, rx_cleaned_per_queue = 0;
++      int tx_cleaned = 0, i, left_over_budget = budget;
++      unsigned long serviced_queues = 0;
++      int num_queues = 0;
++
++      num_queues = gfargrp->num_rx_queues;
++      budget_per_queue = budget/num_queues;
+ 
+       /* Clear IEVENT, so interrupts aren't called again
+        * because of the packets that have already arrived
+        */
+       gfar_write(&regs->ievent, IEVENT_RTX_MASK);
+ 
+-      rstat_rxf = gfar_read(&regs->rstat) & RSTAT_RXF_MASK;
+-
+-      num_act_queues = bitmap_weight(&rstat_rxf, MAX_RX_QS);
+-      if (num_act_queues)
+-              budget_per_q = budget/num_act_queues;
+-
+-      while (1) {
+-              has_tx_work = 0;
+-              for_each_set_bit(i, &gfargrp->tx_bit_map, priv->num_tx_queues) {
+-                      tx_queue = priv->tx_queue[i];
+-                      /* run Tx cleanup to completion */
+-                      if (tx_queue->tx_skbuff[tx_queue->skb_dirtytx]) {
+-                              gfar_clean_tx_ring(tx_queue);
+-                              has_tx_work = 1;
+-                      }
+-              }
++      while (num_queues && left_over_budget) {
++              budget_per_queue = left_over_budget/num_queues;
++              left_over_budget = 0;
+ 
+               for_each_set_bit(i, &gfargrp->rx_bit_map, priv->num_rx_queues) {
+-                      /* skip queue if not active */
+-                      if (!(rstat_rxf & (RSTAT_CLEAR_RXF0 >> i)))
++                      if (test_bit(i, &serviced_queues))
+                               continue;
+-
+                       rx_queue = priv->rx_queue[i];
+-                      work_done_per_q =
+-                              gfar_clean_rx_ring(rx_queue, budget_per_q);
+-                      work_done += work_done_per_q;
+-
+-                      /* finished processing this queue */
+-                      if (work_done_per_q < budget_per_q) {
+-                              /* clear active queue hw indication */
+-                              gfar_write(&regs->rstat,
+-                                         RSTAT_CLEAR_RXF0 >> i);
+-                              rstat_rxf &= ~(RSTAT_CLEAR_RXF0 >> i);
+-                              num_act_queues--;
+-
+-                              if (!num_act_queues)
+-                                      break;
+-                              /* recompute budget per Rx queue */
+-                              budget_per_q =
+-                                      (budget - work_done) / num_act_queues;
++                      tx_queue = priv->tx_queue[rx_queue->qindex];
++
++                      tx_cleaned += gfar_clean_tx_ring(tx_queue);
++                      rx_cleaned_per_queue =
++                              gfar_clean_rx_ring(rx_queue, budget_per_queue);
++                      rx_cleaned += rx_cleaned_per_queue;
++                      if (rx_cleaned_per_queue < budget_per_queue) {
++                              left_over_budget = left_over_budget +
++                                      (budget_per_queue -
++                                       rx_cleaned_per_queue);
++                              set_bit(i, &serviced_queues);
++                              num_queues--;
+                       }
+               }
++      }
+ 
+-              if (work_done >= budget)
+-                      break;
+-
+-              if (!num_act_queues && !has_tx_work) {
++      if (tx_cleaned)
++              return budget;
+ 
+-                      napi_complete(napi);
++      if (rx_cleaned < budget) {
++              napi_complete(napi);
+ 
+-                      /* Clear the halt bit in RSTAT */
+-                      gfar_write(&regs->rstat, gfargrp->rstat);
++              /* Clear the halt bit in RSTAT */
++              gfar_write(&regs->rstat, gfargrp->rstat);
+ 
+-                      gfar_write(&regs->imask, IMASK_DEFAULT);
++              gfar_write(&regs->imask, IMASK_DEFAULT);
+ 
+-                      /* If we are coalescing interrupts, update the timer
+-                       * Otherwise, clear it
+-                       */
+-                      gfar_configure_coalescing(priv, gfargrp->rx_bit_map,
+-                                                gfargrp->tx_bit_map);
+-                      break;
+-              }
++              /* If we are coalescing interrupts, update the timer
++               * Otherwise, clear it
++               */
++              gfar_configure_coalescing(priv, gfargrp->rx_bit_map,
++                                        gfargrp->tx_bit_map);
+       }
+ 
+-      return work_done;
++      return rx_cleaned;
+ }
+ 
+ #ifdef CONFIG_NET_POLL_CONTROLLER
+--- a/drivers/net/ethernet/freescale/gianfar.h
++++ b/drivers/net/ethernet/freescale/gianfar.h
+@@ -291,9 +291,7 @@ extern const char gfar_driver_version[];
+ #define RCTRL_PADDING(x)      ((x << 16) & RCTRL_PAL_MASK)
+ 
+ 
+-#define RSTAT_CLEAR_RHALT     0x00800000
+-#define RSTAT_CLEAR_RXF0      0x00000080
+-#define RSTAT_RXF_MASK                0x000000ff
++#define RSTAT_CLEAR_RHALT       0x00800000
+ 
+ #define TCTRL_IPCSEN          0x00004000
+ #define TCTRL_TUCSEN          0x00002000