Changeset 8136102 in mainline for uspace/srv/hw/netif/dp8390/ne2000.c

Timestamp:

2011-01-11T01:33:58Z (13 years ago)

Author:

Martin Decky <martin@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

6b22c97

Parents:

6643a19 (diff), 7300c37 (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

improve correctness of the NE2000 driver w.r.t. parallelism of the interrupt notification handler

• by masking off interrupts in the kernel interrupt handler, the core of the interrupt notification handler (fetching frames from the network card itself) always runs single-threaded (thus avoiding the issues with fetching of frames multiple times from different fibrils, causing ICMP replies to be duplicated)
• the received frames are buffered locally and then sent to the NIL module with the interrupts unmasked again (thus another notification handler will be scheduled if the sending of the frames to the NIL module blocks)

there is still a synchronization issue without any clear root cause when the network card is flood-pinged even before it is being initialized

File:

• uspace/srv/hw/netif/dp8390/ne2000.c (modified) (7 diffs)

uspace/srv/hw/netif/dp8390/ne2000.c

@@ -68 +68 @@
 #define IRQ_GET_ISR(call)  ((int) IPC_GET_ARG2(call))
 
+/** Return the TSR from the interrupt call.
+ *
+ * @param[in] call The interrupt call.
+ *
+ */
+#define IRQ_GET_TSR(call)  ((int) IPC_GET_ARG3(call))
+
 static int irc_service = 0;
 static int irc_phone = -1;
@@ -76 +83 @@
 static irq_cmd_t ne2k_cmds[] = {
         {
+                /* Read Interrupt Status Register */
                 .cmd = CMD_PIO_READ_8,
                 .addr = NULL,
@@ -81 +89 @@
         },
         {
+                /* Mask supported interrupt causes */
                 .cmd = CMD_BTEST,
-                .value = 0x7f,
+                .value = (ISR_PRX | ISR_PTX | ISR_RXE | ISR_TXE | ISR_OVW |
+                    ISR_CNT | ISR_RDC),
                 .srcarg = 2,
                 .dstarg = 3,
         },
         {
+                /* Predicate for accepting the interrupt */
                 .cmd = CMD_PREDICATE,
-                .value = 2,
+                .value = 4,
                 .srcarg = 3
         },
         {
+                /*
+                 * Mask future interrupts via
+                 * Interrupt Mask Register
+                 */
+                .cmd = CMD_PIO_WRITE_8,
+                .addr = NULL,
+                .value = 0
+        },
+        {
+                /* Acknowledge the current interrupt */
                 .cmd = CMD_PIO_WRITE_A_8,
                 .addr = NULL,
                 .srcarg = 3
+        },
+        {
+                /* Read Transmit Status Register */
+                .cmd = CMD_PIO_READ_8,
+                .addr = NULL,
+                .dstarg = 3
         },
         {
@@ -111 +138 @@
 /** Handle the interrupt notification.
  *
- * This is the interrupt notification function.
+ * This is the interrupt notification function. It is quarantied
+ * that there is only a single instance of this notification
+ * function running at one time until the return from the
+ * ne2k_interrupt() function (where the interrupts are unmasked
+ * again).
  *
  * @param[in] iid  Interrupt notification identifier.
@@ -134 +165 @@
         fibril_rwlock_read_unlock(&netif_globals.lock);
         
-        if (ne2k != NULL)
-                ne2k_interrupt(ne2k, IRQ_GET_ISR(*call), nil_phone, device_id);
+        if (ne2k != NULL) {
+                link_t *frames =
+                    ne2k_interrupt(ne2k, IRQ_GET_ISR(*call), IRQ_GET_TSR(*call));
+                
+                if (frames != NULL) {
+                        while (!list_empty(frames)) {
+                                frame_t *frame =
+                                    list_get_instance(frames->next, frame_t, link);
+                                
+                                list_remove(&frame->link);
+                                nil_received_msg(nil_phone, device_id, frame->packet,
+                                    SERVICE_NONE);
+                                free(frame);
+                        }
+                        
+                        free(frames);
+                }
+        }
 }
 
@@ -265 +312 @@
                 
                 ne2k_cmds[0].addr = ne2k->port + DP_ISR;
-                ne2k_cmds[3].addr = ne2k_cmds[0].addr;
+                ne2k_cmds[3].addr = ne2k->port + DP_IMR;
+                ne2k_cmds[4].addr = ne2k_cmds[0].addr;
                 
                 int rc = ipc_register_irq(ne2k->irq, device->device_id,
@@ -278 +326 @@
                 }
                 
+                change_state(device, NETIF_ACTIVE);
+                
                 if (irc_service)
                         async_msg_1(irc_phone, IRC_ENABLE_INTERRUPT, ne2k->irq);
-                
-                change_state(device, NETIF_ACTIVE);
         }