zte's code,first commit
Change-Id: I9a04da59e459a9bc0d67f101f700d9d7dc8d681b
diff --git a/ap/os/linux/linux-3.4.x/arch/arm/kernel/irq.c b/ap/os/linux/linux-3.4.x/arch/arm/kernel/irq.c
new file mode 100644
index 0000000..6d05f06
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/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/random.h>
+#include <linux/smp.h>
+#include <linux/init.h>
+#include <linux/seq_file.h>
+#include <linux/errno.h>
+#include <linux/list.h>
+#include <linux/kallsyms.h>
+#include <linux/proc_fs.h>
+
+#include <asm/exception.h>
+#include <asm/mach/arch.h>
+#include <asm/mach/irq.h>
+#include <asm/mach/time.h>
+
+/*
+ * No architecture-specific irq_finish function defined in arm/arch/irqs.h.
+ */
+#ifndef irq_finish
+#define irq_finish(irq) do { } while (0)
+#endif
+
+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)
+{
+ struct pt_regs *old_regs = set_irq_regs(regs);
+
+ irq_enter();
+ zxic_trace_irq_enter(irq);
+
+ /*
+ * Some hardware gives randomly wrong interrupts. Rather
+ * than crashing, do something sensible.
+ */
+ if (unlikely(irq >= nr_irqs)) {
+ if (printk_ratelimit())
+ printk(KERN_WARNING "Bad IRQ%u\n", irq);
+ ack_bad_irq(irq);
+ } else {
+ generic_handle_irq(irq);
+ }
+
+ /* AT91 specific workaround */
+ irq_finish(irq);
+
+ zxic_trace_irq_exit(irq);
+ irq_exit();
+ set_irq_regs(old_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) {
+ printk(KERN_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);
+}
+
+void __init init_IRQ(void)
+{
+ machine_desc->init_irq();
+}
+
+#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, true) == 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 && printk_ratelimit())
+ pr_warning("IRQ%u no longer affine to CPU%u\n", i,
+ smp_processor_id());
+ }
+
+ local_irq_restore(flags);
+}
+#endif /* CONFIG_HOTPLUG_CPU */