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-rw-r--r--arch/c6x/kernel/irq.c131
1 files changed, 131 insertions, 0 deletions
diff --git a/arch/c6x/kernel/irq.c b/arch/c6x/kernel/irq.c
new file mode 100644
index 000000000..247e0eb5e
--- /dev/null
+++ b/arch/c6x/kernel/irq.c
@@ -0,0 +1,131 @@
+/*
+ * Copyright (C) 2011-2012 Texas Instruments Incorporated
+ *
+ * This borrows heavily from powerpc version, which is:
+ *
+ * Derived from arch/i386/kernel/irq.c
+ * Copyright (C) 1992 Linus Torvalds
+ * Adapted from arch/i386 by Gary Thomas
+ * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ * Updated and modified by Cort Dougan <cort@fsmlabs.com>
+ * Copyright (C) 1996-2001 Cort Dougan
+ * Adapted for Power Macintosh by Paul Mackerras
+ * Copyright (C) 1996 Paul Mackerras (paulus@cs.anu.edu.au)
+ *
+ * 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.
+ */
+#include <linux/slab.h>
+#include <linux/seq_file.h>
+#include <linux/radix-tree.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/interrupt.h>
+#include <linux/kernel_stat.h>
+
+#include <asm/megamod-pic.h>
+#include <asm/special_insns.h>
+
+unsigned long irq_err_count;
+
+static DEFINE_RAW_SPINLOCK(core_irq_lock);
+
+static void mask_core_irq(struct irq_data *data)
+{
+ unsigned int prio = data->hwirq;
+
+ raw_spin_lock(&core_irq_lock);
+ and_creg(IER, ~(1 << prio));
+ raw_spin_unlock(&core_irq_lock);
+}
+
+static void unmask_core_irq(struct irq_data *data)
+{
+ unsigned int prio = data->hwirq;
+
+ raw_spin_lock(&core_irq_lock);
+ or_creg(IER, 1 << prio);
+ raw_spin_unlock(&core_irq_lock);
+}
+
+static struct irq_chip core_chip = {
+ .name = "core",
+ .irq_mask = mask_core_irq,
+ .irq_unmask = unmask_core_irq,
+};
+
+static int prio_to_virq[NR_PRIORITY_IRQS];
+
+asmlinkage void c6x_do_IRQ(unsigned int prio, struct pt_regs *regs)
+{
+ struct pt_regs *old_regs = set_irq_regs(regs);
+
+ irq_enter();
+
+ generic_handle_irq(prio_to_virq[prio]);
+
+ irq_exit();
+
+ set_irq_regs(old_regs);
+}
+
+static struct irq_domain *core_domain;
+
+static int core_domain_map(struct irq_domain *h, unsigned int virq,
+ irq_hw_number_t hw)
+{
+ if (hw < 4 || hw >= NR_PRIORITY_IRQS)
+ return -EINVAL;
+
+ prio_to_virq[hw] = virq;
+
+ irq_set_status_flags(virq, IRQ_LEVEL);
+ irq_set_chip_and_handler(virq, &core_chip, handle_level_irq);
+ return 0;
+}
+
+static const struct irq_domain_ops core_domain_ops = {
+ .map = core_domain_map,
+ .xlate = irq_domain_xlate_onecell,
+};
+
+void __init init_IRQ(void)
+{
+ struct device_node *np;
+
+ /* Mask all priority IRQs */
+ and_creg(IER, ~0xfff0);
+
+ np = of_find_compatible_node(NULL, NULL, "ti,c64x+core-pic");
+ if (np != NULL) {
+ /* create the core host */
+ core_domain = irq_domain_add_linear(np, NR_PRIORITY_IRQS,
+ &core_domain_ops, NULL);
+ if (core_domain)
+ irq_set_default_host(core_domain);
+ of_node_put(np);
+ }
+
+ printk(KERN_INFO "Core interrupt controller initialized\n");
+
+ /* now we're ready for other SoC controllers */
+ megamod_pic_init();
+
+ /* Clear all general IRQ flags */
+ set_creg(ICR, 0xfff0);
+}
+
+void ack_bad_irq(int irq)
+{
+ printk(KERN_ERR "IRQ: spurious interrupt %d\n", irq);
+ irq_err_count++;
+}
+
+int arch_show_interrupts(struct seq_file *p, int prec)
+{
+ seq_printf(p, "%*s: %10lu\n", prec, "Err", irq_err_count);
+ return 0;
+}