1 files changed, 74 insertions, 91 deletions

diff --git a/arch/xtensa/kernel/traps.c b/arch/xtensa/kernel/traps.c
index 01e0111bf78..eebbfd8c26f 100644
--- a/arch/xtensa/kernel/traps.c
+++ b/arch/xtensa/kernel/traps.c
@@ -11,7 +11,7 @@
  *
  * Essentially rewritten for the Xtensa architecture port.
  *
- * Copyright (C) 2001 - 2005 Tensilica Inc.
+ * Copyright (C) 2001 - 2013 Tensilica Inc.
  *
  * Joe Taylor	<joe@tensilica.com, joetylr@yahoo.com>
  * Chris Zankel	<chris@zankel.net>
@@ -32,11 +32,13 @@
 #include <linux/delay.h>
 #include <linux/hardirq.h>
 
+#include <asm/stacktrace.h>
 #include <asm/ptrace.h>
 #include <asm/timex.h>
 #include <asm/uaccess.h>
 #include <asm/pgtable.h>
 #include <asm/processor.h>
+#include <asm/traps.h>
 
 #ifdef CONFIG_KGDB
 extern int gdb_enter;
@@ -155,7 +157,7 @@ COPROCESSOR(7),
  * 2. it is a temporary memory buffer for the exception handlers.
  */
 
-unsigned long exc_table[EXC_TABLE_SIZE/4];
+DEFINE_PER_CPU(unsigned long, exc_table[EXC_TABLE_SIZE/4]);
 
 void die(const char*, struct pt_regs*, long);
 
@@ -193,30 +195,48 @@ void do_multihit(struct pt_regs *regs, unsigned long exccause)
 }
 
 /*
- * Level-1 interrupt.
- * We currently have no priority encoding.
+ * IRQ handler.
  */
 
-unsigned long ignored_level1_interrupts;
 extern void do_IRQ(int, struct pt_regs *);
 
-void do_interrupt (struct pt_regs *regs)
+void do_interrupt(struct pt_regs *regs)
 {
-	unsigned long intread = get_sr (interrupt);
-	unsigned long intenable = get_sr (intenable);
-	int i, mask;
+	static const unsigned int_level_mask[] = {
+		0,
+		XCHAL_INTLEVEL1_MASK,
+		XCHAL_INTLEVEL2_MASK,
+		XCHAL_INTLEVEL3_MASK,
+		XCHAL_INTLEVEL4_MASK,
+		XCHAL_INTLEVEL5_MASK,
+		XCHAL_INTLEVEL6_MASK,
+		XCHAL_INTLEVEL7_MASK,
+	};
+	struct pt_regs *old_regs = set_irq_regs(regs);
+
+	irq_enter();
+
+	for (;;) {
+		unsigned intread = get_sr(interrupt);
+		unsigned intenable = get_sr(intenable);
+		unsigned int_at_level = intread & intenable;
+		unsigned level;
+
+		for (level = LOCKLEVEL; level > 0; --level) {
+			if (int_at_level & int_level_mask[level]) {
+				int_at_level &= int_level_mask[level];
+				break;
+			}
+		}
 
-	/* Handle all interrupts (no priorities).
-	 * (Clear the interrupt before processing, in case it's
-	 *  edge-triggered or software-generated)
-	 */
+		if (level == 0)
+			break;
 
-	for (i=0, mask = 1; i < XCHAL_NUM_INTERRUPTS; i++, mask <<= 1) {
-		if (mask & (intread & intenable)) {
-			set_sr (mask, intclear);
-			do_IRQ (i,regs);
-		}
+		do_IRQ(__ffs(int_at_level), regs);
 	}
+
+	irq_exit();
+	set_irq_regs(old_regs);
 }
 
 /*
@@ -293,17 +313,31 @@ do_debug(struct pt_regs *regs)
 }
 
 
+static void set_handler(int idx, void *handler)
+{
+	unsigned int cpu;
+
+	for_each_possible_cpu(cpu)
+		per_cpu(exc_table, cpu)[idx] = (unsigned long)handler;
+}
+
 /* Set exception C handler - for temporary use when probing exceptions */
 
 void * __init trap_set_handler(int cause, void *handler)
 {
-	unsigned long *entry = &exc_table[EXC_TABLE_DEFAULT / 4 + cause];
-	void *previous = (void *)*entry;
-	*entry = (unsigned long)handler;
+	void *previous = (void *)per_cpu(exc_table, 0)[
+		EXC_TABLE_DEFAULT / 4 + cause];
+	set_handler(EXC_TABLE_DEFAULT / 4 + cause, handler);
 	return previous;
 }
 
 
+static void trap_init_excsave(void)
+{
+	unsigned long excsave1 = (unsigned long)this_cpu_ptr(exc_table);
+	__asm__ __volatile__("wsr  %0, excsave1\n" : : "a" (excsave1));
+}
+
 /*
  * Initialize dispatch tables.
  *
@@ -317,8 +351,6 @@ void * __init trap_set_handler(int cause, void *handler)
  * See vectors.S for more details.
  */
 
-#define set_handler(idx,handler) (exc_table[idx] = (unsigned long) (handler))
-
 void __init trap_init(void)
 {
 	int i;
@@ -348,10 +380,15 @@ void __init trap_init(void)
 	}
 
 	/* Initialize EXCSAVE_1 to hold the address of the exception table. */
+	trap_init_excsave();
+}
 
-	i = (unsigned long)exc_table;
-	__asm__ __volatile__("wsr  %0, excsave1\n" : : "a" (i));
+#ifdef CONFIG_SMP
+void secondary_trap_init(void)
+{
+	trap_init_excsave();
 }
+#endif
 
 /*
  * This function dumps the current valid window frame and other base registers.
@@ -361,6 +398,8 @@ void show_regs(struct pt_regs * regs)
 {
 	int i, wmask;
 
+	show_regs_print_info(KERN_DEFAULT);
+
 	wmask = regs->wmask & ~1;
 
 	for (i = 0; i < 16; i++) {
@@ -380,73 +419,25 @@ void show_regs(struct pt_regs * regs)
 		       regs->syscall);
 }
 
-static __always_inline unsigned long *stack_pointer(struct task_struct *task)
-{
-	unsigned long *sp;
-
-	if (!task || task == current)
-		__asm__ __volatile__ ("mov %0, a1\n" : "=a"(sp));
-	else
-		sp = (unsigned long *)task->thread.sp;
-
-	return sp;
-}
-
-static inline void spill_registers(void)
+static int show_trace_cb(struct stackframe *frame, void *data)
 {
-	unsigned int a0, ps;
-
-	__asm__ __volatile__ (
-		"movi	a14, " __stringify(PS_EXCM_BIT | 1) "\n\t"
-		"mov	a12, a0\n\t"
-		"rsr	a13, sar\n\t"
-		"xsr	a14, ps\n\t"
-		"movi	a0, _spill_registers\n\t"
-		"rsync\n\t"
-		"callx0 a0\n\t"
-		"mov	a0, a12\n\t"
-		"wsr	a13, sar\n\t"
-		"wsr	a14, ps\n\t"
-		:: "a" (&a0), "a" (&ps)
-		: "a2", "a3", "a4", "a7", "a11", "a12", "a13", "a14", "a15",
-		  "memory");
+	if (kernel_text_address(frame->pc)) {
+		printk(" [<%08lx>] ", frame->pc);
+		print_symbol("%s\n", frame->pc);
+	}
+	return 0;
 }
 
 void show_trace(struct task_struct *task, unsigned long *sp)
 {
-	unsigned long a0, a1, pc;
-	unsigned long sp_start, sp_end;
-
-	if (sp)
-		a1 = (unsigned long)sp;
-	else
-		a1 = (unsigned long)stack_pointer(task);
-
-	sp_start = a1 & ~(THREAD_SIZE-1);
-	sp_end = sp_start + THREAD_SIZE;
+	if (!sp)
+		sp = stack_pointer(task);
 
 	printk("Call Trace:");
 #ifdef CONFIG_KALLSYMS
 	printk("\n");
 #endif
-	spill_registers();
-
-	while (a1 > sp_start && a1 < sp_end) {
-		sp = (unsigned long*)a1;
-
-		a0 = *(sp - 4);
-		a1 = *(sp - 3);
-
-		if (a1 <= (unsigned long) sp)
-			break;
-
-		pc = MAKE_PC_FROM_RA(a0, a1);
-
-		if (kernel_text_address(pc)) {
-			printk(" [<%08lx>] ", pc);
-			print_symbol("%s\n", pc);
-		}
-	}
+	walk_stackframe(sp, show_trace_cb, NULL);
 	printk("\n");
 }
 
@@ -479,14 +470,6 @@ void show_stack(struct task_struct *task, unsigned long *sp)
 	show_trace(task, stack);
 }
 
-void dump_stack(void)
-{
-	show_stack(current, NULL);
-}
-
-EXPORT_SYMBOL(dump_stack);
-
-
 void show_code(unsigned int *pc)
 {
 	long i;
@@ -524,7 +507,7 @@ void die(const char * str, struct pt_regs * regs, long err)
 	if (!user_mode(regs))
 		show_stack(NULL, (unsigned long*)regs->areg[1]);
 
-	add_taint(TAINT_DIE);
+	add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
 	spin_unlock_irq(&die_lock);
 
 	if (in_interrupt())