Networking finally works stable, although not really clean. Something causes spurious interrupts and a handler for this fixed it for now.

sys/BaS.c

@@ -270,6 +270,15 @@ NIF nif1;
 NIF nif2;
 #endif
 
+bool spurious_interrupt_handler(void *arg1, void *arg2)
+{
+    dbg("IMRH=%lx, IMRL=%lx\r\n", MCF_INTC_IMRH, MCF_INTC_IMRL);
+    dbg("IPRH=%lx, IPRL=%lx\r\n", MCF_INTC_IPRH, MCF_INTC_IPRL);
+    dbg("IRLR=%x\r\n", MCF_INTC_IRLR);
+
+    return true;
+}
+
 /*
  * initialize the interrupt handler tables to dispatch interrupt requests from Coldfire devices
  */
@@ -277,12 +286,20 @@ void init_isr(void)
 {
     isr_init();     /* need to call that explicitely, otherwise isr table might be full */
 
+    /*
+     * register spurious interrupt handler
+     */
+    if (!isr_register_handler(24, 6, 6, spurious_interrupt_handler, NULL, NULL))
+    {
+        dbg("unable to register spurious interrupt handler\r\n");
+    }
+
     /*
      * register the FEC interrupt handler
      */
     if (!isr_register_handler(64 + INT_SOURCE_FEC0, 5, 1, fec0_interrupt_handler, NULL, (void *) &nif1))
     {
-        err("unable to register isr for FEC0\r\n");
+        dbg("unable to register isr for FEC0\r\n");
     }
 
     /*
@@ -291,7 +308,7 @@ void init_isr(void)
 
     if (!isr_register_handler(64 + INT_SOURCE_DMA, 5, 3, dma_interrupt_handler, NULL, NULL))
     {
-        err("unable to register isr for DMA\r\n");
+        dbg("unable to register isr for DMA\r\n");
     }
 
 #ifdef MACHINE_FIREBEE
@@ -300,7 +317,7 @@ void init_isr(void)
      */
     if (!isr_register_handler(64 + INT_SOURCE_GPT0, 5, 2, gpt0_interrupt_handler, NULL, NULL))
     {
-        err("unable to register isr for GPT0 timer\r\n");
+        dbg("unable to register isr for GPT0 timer\r\n");
     }
 
     /*
@@ -308,7 +325,7 @@ void init_isr(void)
      */
     if (!isr_register_handler(64 + INT_SOURCE_PSC3, 5, 5, pic_interrupt_handler, NULL, NULL))
     {
-        err("Error: unable to register ISR for PSC3\r\n");
+        dbg("Error: unable to register ISR for PSC3\r\n");
     }
 #endif /* MACHINE_FIREBEE */
 
@@ -317,7 +334,7 @@ void init_isr(void)
      */
     if (!isr_register_handler(64 + INT_SOURCE_XLBPCI, 7, 0, xlbpci_interrupt_handler, NULL, NULL))
     {
-        err("Error: unable to register isr for XLB PCI interrupts\r\n");
+        dbg("Error: unable to register isr for XLB PCI interrupts\r\n");
     }
 
     MCF_XLB_XARB_IMR = MCF_XLB_XARB_IMR_SEAE |      /* slave error acknowledge interrupt */
@@ -330,7 +347,7 @@ void init_isr(void)
 
     if (!isr_register_handler(64 + INT_SOURCE_PCIARB, 7, 1, pciarb_interrupt_handler, NULL, NULL))
     {
-        err("Error: unable to register isr for PCIARB interrupts\r\n");
+        dbg("Error: unable to register isr for PCIARB interrupts\r\n");
 
         return;
     }
@@ -442,7 +459,10 @@ void BaS(void)
     init_isr();
 
     enable_coldfire_interrupts();
+    MCF_INTC_IMRH = 0;
+    MCF_INTC_IMRL = 0;
     dma_irq_enable();
+    fec_irq_enable(0, 5, 1);
 
     init_pci();
     // video_init();

sys/exceptions.S

@@ -178,6 +178,8 @@ init_vec_loop:
 		subq.l  #1,d0
 		bne init_vec_loop
 
+// set individual interrupt handler assignments
+
 		move.l  #__SUP_SP,(a0)              // set initial stack pointer at start of exception vector table
 
 		lea reset_vector(pc),a1             // set reset vector
@@ -186,6 +188,10 @@ init_vec_loop:
 		lea access(pc),a1                   // set illegal access exception handler
 		move.l  a1,0x08(a0)
 
+// install spurious interrupt handler
+		lea	_lowlevel_isr_handler,a1
+		move.l	a1,0x60(a0)
+
 // trap #0 (without any parameters for now) is used to provide BaS' driver addresses to the OS
 		lea _get_bas_drivers(pc),a1
 		move.l  a1,0x80(a0)                 // trap #0 exception vector
@@ -259,7 +265,7 @@ _std_exc_vec:
 		movem.l d0/a5,(sp)                  // save registers
 		move.w  8(sp),d0                    // fetch vector
 		and.l   #0x3fc,d0                   // mask out vector number
-#define DBG_EXC
+//#define DBG_EXC
 #ifdef DBG_EXC
 		// printout vector number of exception
 

sys/interrupts.c

@@ -117,7 +117,7 @@ bool isr_enable_int_source(int int_source)
     }
     else
     {
-        err("vector %d does not correspond to an internal interrupt source\r\n");
+        dbg("vector %d does not correspond to an internal interrupt source\r\n");
         return false;
     }
 
@@ -165,13 +165,13 @@ bool isr_register_handler(int vector, int level, int priority, bool (*handler)(v
 
             if (!isr_enable_int_source(int_source))
             {
-                err("failed to enable internal interrupt souce %d in IMRL/IMRH\r\n", int_source);
+                dbg("failed to enable internal interrupt souce %d in IMRL/IMRH\r\n", int_source);
                 return false;
             }
 
             if (!isr_set_prio_and_level(int_source, priority, level))
             {
-                err("failed to set priority and level for interrupt source %d\r\n", int_source);
+                dbg("failed to set priority and level for interrupt source %d\r\n", int_source);
                 return false;
             }