m68k/mac: Improve NMI handler

mac_nmi_handler() is useless in its present form and locks up my PowerBook
180. Let's throw out the dead code and make it do something useful: print
a register dump and a stack trace.

mac_debug_handler() is also dead code. Remove it along with its static
data.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

1 files changed, 8 insertions, 59 deletions

diff --git a/arch/m68k/mac/macints.c b/arch/m68k/mac/macints.c
index 9f98c0871901..f9672bbd566f 100644
--- a/arch/m68k/mac/macints.c
+++ b/arch/m68k/mac/macints.c
@@ -127,12 +127,9 @@
 
 #define SHUTUP_SONIC
 
-/*
- * console_loglevel determines NMI handler function
- */
+extern void show_registers(struct pt_regs *);
 
 irqreturn_t mac_nmi_handler(int, void *);
-irqreturn_t mac_debug_handler(int, void *);
 
 /* #define DEBUG_MACINTS */
 
@@ -276,65 +273,17 @@ static void mac_irq_shutdown(struct irq_data *data)
                 mac_irq_disable(data);
 }
 
-static int num_debug[8];
-
-irqreturn_t mac_debug_handler(int irq, void *dev_id)
-{
-        if (num_debug[irq] < 10) {
-                printk("DEBUG: Unexpected IRQ %d\n", irq);
-                num_debug[irq]++;
-        }
-        return IRQ_HANDLED;
-}
-
-static int in_nmi;
-static volatile int nmi_hold;
+static volatile int in_nmi;
 
 irqreturn_t mac_nmi_handler(int irq, void *dev_id)
 {
-        int i;
-        /*
-         * generate debug output on NMI switch if 'debug' kernel option given
-         * (only works with Penguin!)
-         */
-
-        in_nmi++;
-        for (i=0; i<100; i++)
-                udelay(1000);
-
-        if (in_nmi == 1) {
-                nmi_hold = 1;
-                printk("... pausing, press NMI to resume ...");
-        } else {
-                printk(" ok!\n");
-                nmi_hold = 0;
-        }
+        if (in_nmi)
+                return IRQ_HANDLED;
+        in_nmi = 1;
 
-        barrier();
+        pr_info("Non-Maskable Interrupt\n");
+        show_registers(get_irq_regs());
 
-        while (nmi_hold == 1)
-                udelay(1000);
-
-        if (console_loglevel >= 8) {
-#if 0
-                struct pt_regs *fp = get_irq_regs();
-                show_state();
-                printk("PC: %08lx\nSR: %04x  SP: %p\n", fp->pc, fp->sr, fp);
-                printk("d0: %08lx    d1: %08lx    d2: %08lx    d3: %08lx\n",
-                       fp->d0, fp->d1, fp->d2, fp->d3);
-                printk("d4: %08lx    d5: %08lx    a0: %08lx    a1: %08lx\n",
-                       fp->d4, fp->d5, fp->a0, fp->a1);
-
-                if (STACK_MAGIC != *(unsigned long *)current->kernel_stack_page)
-                        printk("Corrupted stack page\n");
-                printk("Process %s (pid: %d, stackpage=%08lx)\n",
-                        current->comm, current->pid, current->kernel_stack_page);
-                if (intr_count == 1)
-                        dump_stack((struct frame *)fp);
-#else
-                /* printk("NMI "); */
-#endif
-        }
-        in_nmi--;
+        in_nmi = 0;
         return IRQ_HANDLED;
 }