summaryrefslogtreecommitdiff
path: root/arch/blackfin/kernel/irqchip.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/blackfin/kernel/irqchip.c')
-rw-r--r--arch/blackfin/kernel/irqchip.c147
1 files changed, 147 insertions, 0 deletions
diff --git a/arch/blackfin/kernel/irqchip.c b/arch/blackfin/kernel/irqchip.c
new file mode 100644
index 000000000000..df5bf022cf79
--- /dev/null
+++ b/arch/blackfin/kernel/irqchip.c
@@ -0,0 +1,147 @@
+/*
+ * File: arch/blackfin/kernel/irqchip.c
+ * Based on:
+ * Author:
+ *
+ * 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
+ */
+
+#include <linux/kernel_stat.h>
+#include <linux/module.h>
+#include <linux/random.h>
+#include <linux/seq_file.h>
+#include <linux/kallsyms.h>
+#include <linux/interrupt.h>
+#include <linux/irq.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)
+{
+}
+
+void ack_bad_irq(unsigned int irq)
+{
+ irq_err_count += 1;
+ 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,
+};
+
+int show_interrupts(struct seq_file *p, void *v)
+{
+ 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);
+ }
+ return 0;
+}
+
+/*
+ * do_IRQ handles all hardware IRQ's. Decoded IRQs should not
+ * come via this function. Instead, they should provide their
+ * own 'handler'
+ */
+
+#ifdef CONFIG_DO_IRQ_L1
+asmlinkage void asm_do_IRQ(unsigned int irq, struct pt_regs *regs)__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;
+
+ old_regs = set_irq_regs(regs);
+
+ /*
+ * Some hardware gives randomly wrong interrupts. Rather
+ * than crashing, do something sensible.
+ */
+ if (irq >= NR_IRQS)
+ desc = &bad_irq_desc;
+
+ irq_enter();
+
+ 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);
+}
+
+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();
+}