Initial import

1 files changed, 198 insertions, 0 deletions

diff --git a/arch/arm/kernel/irq.c b/arch/arm/kernel/irq.c
new file mode 100644
index 000000000..350f188c9
--- /dev/null
+++ b/arch/arm/kernel/irq.c
@@ -0,0 +1,198 @@
+/*
+ *  linux/arch/arm/kernel/irq.c
+ *
+ *  Copyright (C) 1992 Linus Torvalds
+ *  Modifications for ARM processor Copyright (C) 1995-2000 Russell King.
+ *
+ *  Support for Dynamic Tick Timer Copyright (C) 2004-2005 Nokia Corporation.
+ *  Dynamic Tick Timer written by Tony Lindgren <tony@atomide.com> and
+ *  Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com>.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ *  This file contains the code used by various IRQ handling routines:
+ *  asking for different IRQ's should be done through these routines
+ *  instead of just grabbing them. Thus setups with different IRQ numbers
+ *  shouldn't result in any weird surprises, and installing new handlers
+ *  should be easier.
+ *
+ *  IRQ's are in fact implemented a bit like signal handlers for the kernel.
+ *  Naturally it's not a 1:1 relation, but there are similarities.
+ */
+#include <linux/kernel_stat.h>
+#include <linux/signal.h>
+#include <linux/ioport.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqchip.h>
+#include <linux/random.h>
+#include <linux/smp.h>
+#include <linux/init.h>
+#include <linux/seq_file.h>
+#include <linux/ratelimit.h>
+#include <linux/errno.h>
+#include <linux/list.h>
+#include <linux/kallsyms.h>
+#include <linux/proc_fs.h>
+#include <linux/export.h>
+
+#include <asm/hardware/cache-l2x0.h>
+#include <asm/exception.h>
+#include <asm/mach/arch.h>
+#include <asm/mach/irq.h>
+#include <asm/mach/time.h>
+
+unsigned long irq_err_count;
+
+int arch_show_interrupts(struct seq_file *p, int prec)
+{
+#ifdef CONFIG_FIQ
+	show_fiq_list(p, prec);
+#endif
+#ifdef CONFIG_SMP
+	show_ipi_list(p, prec);
+#endif
+	seq_printf(p, "%*s: %10lu\n", prec, "Err", irq_err_count);
+	return 0;
+}
+
+/*
+ * handle_IRQ handles all hardware IRQ's.  Decoded IRQs should
+ * not come via this function.  Instead, they should provide their
+ * own 'handler'.  Used by platform code implementing C-based 1st
+ * level decoding.
+ */
+void handle_IRQ(unsigned int irq, struct pt_regs *regs)
+{
+	__handle_domain_irq(NULL, irq, false, regs);
+}
+
+/*
+ * asm_do_IRQ is the interface to be used from assembly code.
+ */
+asmlinkage void __exception_irq_entry
+asm_do_IRQ(unsigned int irq, struct pt_regs *regs)
+{
+	handle_IRQ(irq, regs);
+}
+
+void set_irq_flags(unsigned int irq, unsigned int iflags)
+{
+	unsigned long clr = 0, set = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
+
+	if (irq >= nr_irqs) {
+		pr_err("Trying to set irq flags for IRQ%d\n", irq);
+		return;
+	}
+
+	if (iflags & IRQF_VALID)
+		clr |= IRQ_NOREQUEST;
+	if (iflags & IRQF_PROBE)
+		clr |= IRQ_NOPROBE;
+	if (!(iflags & IRQF_NOAUTOEN))
+		clr |= IRQ_NOAUTOEN;
+	/* Order is clear bits in "clr" then set bits in "set" */
+	irq_modify_status(irq, clr, set & ~clr);
+}
+EXPORT_SYMBOL_GPL(set_irq_flags);
+
+void __init init_IRQ(void)
+{
+	int ret;
+
+	if (IS_ENABLED(CONFIG_OF) && !machine_desc->init_irq)
+		irqchip_init();
+	else
+		machine_desc->init_irq();
+
+	if (IS_ENABLED(CONFIG_OF) && IS_ENABLED(CONFIG_CACHE_L2X0) &&
+	    (machine_desc->l2c_aux_mask || machine_desc->l2c_aux_val)) {
+		if (!outer_cache.write_sec)
+			outer_cache.write_sec = machine_desc->l2c_write_sec;
+		ret = l2x0_of_init(machine_desc->l2c_aux_val,
+				   machine_desc->l2c_aux_mask);
+		if (ret)
+			pr_err("L2C: failed to init: %d\n", ret);
+	}
+}
+
+#ifdef CONFIG_MULTI_IRQ_HANDLER
+void __init set_handle_irq(void (*handle_irq)(struct pt_regs *))
+{
+	if (handle_arch_irq)
+		return;
+
+	handle_arch_irq = handle_irq;
+}
+#endif
+
+#ifdef CONFIG_SPARSE_IRQ
+int __init arch_probe_nr_irqs(void)
+{
+	nr_irqs = machine_desc->nr_irqs ? machine_desc->nr_irqs : NR_IRQS;
+	return nr_irqs;
+}
+#endif
+
+#ifdef CONFIG_HOTPLUG_CPU
+static bool migrate_one_irq(struct irq_desc *desc)
+{
+	struct irq_data *d = irq_desc_get_irq_data(desc);
+	const struct cpumask *affinity = d->affinity;
+	struct irq_chip *c;
+	bool ret = false;
+
+	/*
+	 * If this is a per-CPU interrupt, or the affinity does not
+	 * include this CPU, then we have nothing to do.
+	 */
+	if (irqd_is_per_cpu(d) || !cpumask_test_cpu(smp_processor_id(), affinity))
+		return false;
+
+	if (cpumask_any_and(affinity, cpu_online_mask) >= nr_cpu_ids) {
+		affinity = cpu_online_mask;
+		ret = true;
+	}
+
+	c = irq_data_get_irq_chip(d);
+	if (!c->irq_set_affinity)
+		pr_debug("IRQ%u: unable to set affinity\n", d->irq);
+	else if (c->irq_set_affinity(d, affinity, false) == IRQ_SET_MASK_OK && ret)
+		cpumask_copy(d->affinity, affinity);
+
+	return ret;
+}
+
+/*
+ * The current CPU has been marked offline.  Migrate IRQs off this CPU.
+ * If the affinity settings do not allow other CPUs, force them onto any
+ * available CPU.
+ *
+ * Note: we must iterate over all IRQs, whether they have an attached
+ * action structure or not, as we need to get chained interrupts too.
+ */
+void migrate_irqs(void)
+{
+	unsigned int i;
+	struct irq_desc *desc;
+	unsigned long flags;
+
+	local_irq_save(flags);
+
+	for_each_irq_desc(i, desc) {
+		bool affinity_broken;
+
+		raw_spin_lock(&desc->lock);
+		affinity_broken = migrate_one_irq(desc);
+		raw_spin_unlock(&desc->lock);
+
+		if (affinity_broken)
+			pr_warn_ratelimited("IRQ%u no longer affine to CPU%u\n",
+				i, smp_processor_id());
+	}
+
+	local_irq_restore(flags);
+}
+#endif /* CONFIG_HOTPLUG_CPU */