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Diffstat (limited to 'arch/blackfin/kernel/irqchip.c')
-rw-r--r--arch/blackfin/kernel/irqchip.c163
1 files changed, 70 insertions, 93 deletions
diff --git a/arch/blackfin/kernel/irqchip.c b/arch/blackfin/kernel/irqchip.c
index 73647c15877..0ba25764b8c 100644
--- a/arch/blackfin/kernel/irqchip.c
+++ b/arch/blackfin/kernel/irqchip.c
@@ -1,30 +1,7 @@
/*
- * File: arch/blackfin/kernel/irqchip.c
- * Based on:
- * Author:
+ * Copyright 2005-2009 Analog Devices Inc.
*
- * Created:
- * Description: This file contains the simple DMA Implementation for Blackfin
- *
- * Modified:
- * Copyright 2004-2006 Analog Devices Inc.
- *
- * Bugs: Enter bugs at http://blackfin.uclinux.org/
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, see the file COPYING, or write
- * to the Free Software Foundation, Inc.,
- * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ * Licensed under the GPL-2 or later
*/
#include <linux/kernel_stat.h>
@@ -34,100 +11,108 @@
#include <linux/kallsyms.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
+#include <linux/seq_file.h>
+#include <asm/irq_handler.h>
#include <asm/trace.h>
+#include <asm/pda.h>
-static unsigned long irq_err_count;
-static spinlock_t irq_controller_lock;
-
-/*
- * Dummy mask/unmask handler
- */
-void dummy_mask_unmask_irq(unsigned int irq)
-{
-}
-
+static atomic_t irq_err_count;
void ack_bad_irq(unsigned int irq)
{
- irq_err_count += 1;
+ atomic_inc(&irq_err_count);
printk(KERN_ERR "IRQ: spurious interrupt %d\n", irq);
}
-EXPORT_SYMBOL(ack_bad_irq);
-
-static struct irq_chip bad_chip = {
- .ack = dummy_mask_unmask_irq,
- .mask = dummy_mask_unmask_irq,
- .unmask = dummy_mask_unmask_irq,
-};
static struct irq_desc bad_irq_desc = {
- .chip = &bad_chip,
.handle_irq = handle_bad_irq,
- .depth = 1,
+ .lock = __RAW_SPIN_LOCK_UNLOCKED(bad_irq_desc.lock),
};
-int show_interrupts(struct seq_file *p, void *v)
+#ifdef CONFIG_CPUMASK_OFFSTACK
+/* We are not allocating a variable-sized bad_irq_desc.affinity */
+#error "Blackfin architecture does not support CONFIG_CPUMASK_OFFSTACK."
+#endif
+
+#ifdef CONFIG_PROC_FS
+int arch_show_interrupts(struct seq_file *p, int prec)
{
- int i = *(loff_t *) v;
- struct irqaction *action;
- unsigned long flags;
-
- if (i < NR_IRQS) {
- spin_lock_irqsave(&irq_desc[i].lock, flags);
- action = irq_desc[i].action;
- if (!action)
- goto unlock;
-
- seq_printf(p, "%3d: %10u ", i, kstat_irqs(i));
- seq_printf(p, " %s", action->name);
- for (action = action->next; action; action = action->next)
- seq_printf(p, ", %s", action->name);
-
- seq_putc(p, '\n');
- unlock:
- spin_unlock_irqrestore(&irq_desc[i].lock, flags);
- } else if (i == NR_IRQS) {
- seq_printf(p, "Err: %10lu\n", irq_err_count);
- }
+ int j;
+
+ seq_printf(p, "%*s: ", prec, "NMI");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ", cpu_pda[j].__nmi_count);
+ seq_printf(p, " CORE Non Maskable Interrupt\n");
+ seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
return 0;
}
+#endif
+
+#ifdef CONFIG_DEBUG_STACKOVERFLOW
+static void check_stack_overflow(int irq)
+{
+ /* Debugging check for stack overflow: is there less than STACK_WARN free? */
+ long sp = __get_SP() & (THREAD_SIZE - 1);
+
+ if (unlikely(sp < (sizeof(struct thread_info) + STACK_WARN))) {
+ dump_stack();
+ pr_emerg("irq%i: possible stack overflow only %ld bytes free\n",
+ irq, sp - sizeof(struct thread_info));
+ }
+}
+#else
+static inline void check_stack_overflow(int irq) { }
+#endif
+
+#ifndef CONFIG_IPIPE
+static void maybe_lower_to_irq14(void)
+{
+ unsigned short pending, other_ints;
+
+ /*
+ * If we're the only interrupt running (ignoring IRQ15 which
+ * is for syscalls), lower our priority to IRQ14 so that
+ * softirqs run at that level. If there's another,
+ * lower-level interrupt, irq_exit will defer softirqs to
+ * that. If the interrupt pipeline is enabled, we are already
+ * running at IRQ14 priority, so we don't need this code.
+ */
+ CSYNC();
+ pending = bfin_read_IPEND() & ~0x8000;
+ other_ints = pending & (pending - 1);
+ if (other_ints == 0)
+ lower_to_irq14();
+}
+#else
+static inline void maybe_lower_to_irq14(void) { }
+#endif
/*
* do_IRQ handles all hardware IRQs. Decoded IRQs should not
* come via this function. Instead, they should provide their
* own 'handler'
*/
-
#ifdef CONFIG_DO_IRQ_L1
__attribute__((l1_text))
#endif
asmlinkage void asm_do_IRQ(unsigned int irq, struct pt_regs *regs)
{
- struct pt_regs *old_regs;
- struct irq_desc *desc = irq_desc + irq;
- unsigned short pending, other_ints;
+ struct pt_regs *old_regs = set_irq_regs(regs);
+
+ irq_enter();
- old_regs = set_irq_regs(regs);
+ check_stack_overflow(irq);
/*
* Some hardware gives randomly wrong interrupts. Rather
* than crashing, do something sensible.
*/
if (irq >= NR_IRQS)
- desc = &bad_irq_desc;
+ handle_bad_irq(irq, &bad_irq_desc);
+ else
+ generic_handle_irq(irq);
- irq_enter();
+ maybe_lower_to_irq14();
- generic_handle_irq(irq);
-
- /* If we're the only interrupt running (ignoring IRQ15 which is for
- syscalls), lower our priority to IRQ14 so that softirqs run at
- that level. If there's another, lower-level interrupt, irq_exit
- will defer softirqs to that. */
- CSYNC();
- pending = bfin_read_IPEND() & ~0x8000;
- other_ints = pending & (pending - 1);
- if (other_ints == 0)
- lower_to_irq14();
irq_exit();
set_irq_regs(old_regs);
@@ -135,14 +120,6 @@ asmlinkage void asm_do_IRQ(unsigned int irq, struct pt_regs *regs)
void __init init_IRQ(void)
{
- struct irq_desc *desc;
- int irq;
-
- spin_lock_init(&irq_controller_lock);
- for (irq = 0, desc = irq_desc; irq < NR_IRQS; irq++, desc++) {
- *desc = bad_irq_desc;
- }
-
init_arch_irq();
#ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND