MN10300: And Panasonic AM34 subarch and implement SMP

Implement the Panasonic MN10300 AM34 CPU subarch and implement SMP support for
MN10300.  Also implement support for the MN2WS0060 processor and the ASB2364
evaluation board which are AM34 based.

Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
Signed-off-by: Kiyoshi Owada <owada.kiyoshi@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>

1 files changed, 61 insertions, 39 deletions

diff --git a/arch/mn10300/kernel/mn10300-watchdog.c b/arch/mn10300/kernel/mn10300-watchdog.c
index f362d9d138f1..965dd61656c3 100644
--- a/arch/mn10300/kernel/mn10300-watchdog.c
+++ b/arch/mn10300/kernel/mn10300-watchdog.c
@@ -30,7 +30,7 @@
 static DEFINE_SPINLOCK(watchdog_print_lock);
 static unsigned int watchdog;
 static unsigned int watchdog_hz = 1;
-unsigned int watchdog_alert_counter;
+unsigned int watchdog_alert_counter[NR_CPUS];
 
 EXPORT_SYMBOL(touch_nmi_watchdog);
 
@@ -39,9 +39,6 @@ EXPORT_SYMBOL(touch_nmi_watchdog);
  * is to check its timer makes IRQ counts. If they are not
  * changing then that CPU has some problem.
  *
- * as these watchdog NMI IRQs are generated on every CPU, we only
- * have to check the current processor.
- *
  * since NMIs dont listen to _any_ locks, we have to be extremely
  * careful not to rely on unsafe variables. The printk might lock
  * up though, so we have to break up any console locks first ...
@@ -69,8 +66,8 @@ int __init check_watchdog(void)
 
         printk(KERN_INFO "OK.\n");
 
-        /* now that we know it works we can reduce NMI frequency to
-         * something more reasonable; makes a difference in some configs
+        /* now that we know it works we can reduce NMI frequency to something
+         * more reasonable; makes a difference in some configs
          */
         watchdog_hz = 1;
 
@@ -121,15 +118,22 @@ void __init watchdog_go(void)
         }
 }
 
+#ifdef CONFIG_SMP
+static void watchdog_dump_register(void *dummy)
+{
+        printk(KERN_ERR "--- Register Dump (CPU%d) ---\n", CPUID);
+        show_registers(__frame);
+}
+#endif
+
 asmlinkage
 void watchdog_interrupt(struct pt_regs *regs, enum exception_code excep)
 {
-
         /*
          * Since current-> is always on the stack, and we always switch
          * the stack NMI-atomically, it's safe to use smp_processor_id().
          */
-        int sum, cpu = smp_processor_id();
+        int sum, cpu;
         int irq = NMIIRQ;
         u8 wdt, tmp;
 
@@ -138,43 +142,61 @@ void watchdog_interrupt(struct pt_regs *regs, enum exception_code excep)
         tmp = WDCTR;
         NMICR = NMICR_WDIF;
 
-        nmi_count(cpu)++;
+        nmi_count(smp_processor_id())++;
         kstat_incr_irqs_this_cpu(irq, irq_to_desc(irq));
-        sum = irq_stat[cpu].__irq_count;
-
-        if (last_irq_sums[cpu] == sum) {
-                /*
-                 * Ayiee, looks like this CPU is stuck ...
-                 * wait a few IRQs (5 seconds) before doing the oops ...
-                 */
-                watchdog_alert_counter++;
-                if (watchdog_alert_counter == 5 * watchdog_hz) {
-                        spin_lock(&watchdog_print_lock);
+
+        for_each_online_cpu(cpu) {
+
+                sum = irq_stat[cpu].__irq_count;
+
+                if ((last_irq_sums[cpu] == sum)
+#if defined(CONFIG_GDBSTUB) && defined(CONFIG_SMP)
+                        && !(CHK_GDBSTUB_BUSY()
+                             || atomic_read(&cpu_doing_single_step))
+#endif
+                        ) {
                         /*
-                         * We are in trouble anyway, lets at least try
-                         * to get a message out.
+                         * Ayiee, looks like this CPU is stuck ...
+                         * wait a few IRQs (5 seconds) before doing the oops ...
                          */
-                        bust_spinlocks(1);
-                        printk(KERN_ERR
-                               "NMI Watchdog detected LOCKUP on CPU%d,"
-                               " pc %08lx, registers:\n",
-                               cpu, regs->pc);
-                        show_registers(regs);
-                        printk("console shuts up ...\n");
-                        console_silent();
-                        spin_unlock(&watchdog_print_lock);
-                        bust_spinlocks(0);
+                        watchdog_alert_counter[cpu]++;
+                        if (watchdog_alert_counter[cpu] == 5 * watchdog_hz) {
+                                spin_lock(&watchdog_print_lock);
+                                /*
+                                 * We are in trouble anyway, lets at least try
+                                 * to get a message out.
+                                 */
+                                bust_spinlocks(1);
+                                printk(KERN_ERR
+                                       "NMI Watchdog detected LOCKUP on CPU%d,"
+                                       " pc %08lx, registers:\n",
+                                       cpu, regs->pc);
+#ifdef CONFIG_SMP
+                                printk(KERN_ERR
+                                       "--- Register Dump (CPU%d) ---\n",
+                                       CPUID);
+#endif
+                                show_registers(regs);
+#ifdef CONFIG_SMP
+                                smp_nmi_call_function(watchdog_dump_register,
+                                        NULL, 1);
+#endif
+                                printk(KERN_NOTICE "console shuts up ...\n");
+                                console_silent();
+                                spin_unlock(&watchdog_print_lock);
+                                bust_spinlocks(0);
 #ifdef CONFIG_GDBSTUB
-                        if (gdbstub_busy)
-                                gdbstub_exception(regs, excep);
-                        else
-                                gdbstub_intercept(regs, excep);
+                                if (CHK_GDBSTUB_BUSY_AND_ACTIVE())
+                                        gdbstub_exception(regs, excep);
+                                else
+                                        gdbstub_intercept(regs, excep);
 #endif
-                        do_exit(SIGSEGV);
+                                do_exit(SIGSEGV);
+                        }
+                } else {
+                        last_irq_sums[cpu] = sum;
+                        watchdog_alert_counter[cpu] = 0;
                 }
-        } else {
-                last_irq_sums[cpu] = sum;
-                watchdog_alert_counter = 0;
         }
 
         WDCTR = wdt | WDCTR_WDRST;