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-rw-r--r--arch/metag/kernel/kick.c110
1 files changed, 0 insertions, 110 deletions
diff --git a/arch/metag/kernel/kick.c b/arch/metag/kernel/kick.c
deleted file mode 100644
index beb3776..0000000
--- a/arch/metag/kernel/kick.c
+++ /dev/null
@@ -1,110 +0,0 @@
-/*
- * Copyright (C) 2009 Imagination Technologies
- *
- * This file is subject to the terms and conditions of the GNU General Public
- * License. See the file COPYING in the main directory of this archive
- * for more details.
- *
- * The Meta KICK interrupt mechanism is generally a useful feature, so
- * we provide an interface for registering multiple interrupt
- * handlers. All the registered interrupt handlers are "chained". When
- * a KICK interrupt is received the first function in the list is
- * called. If that interrupt handler cannot handle the KICK the next
- * one is called, then the next until someone handles it (or we run
- * out of functions). As soon as one function handles the interrupt no
- * other handlers are called.
- *
- * The only downside of chaining interrupt handlers is that each
- * handler must be able to detect whether the KICK was intended for it
- * or not. For example, when the IPI handler runs and it sees that
- * there are no IPI messages it must not signal that the KICK was
- * handled, thereby giving the other handlers a chance to run.
- *
- * The reason that we provide our own interface for calling KICK
- * handlers instead of using the generic kernel infrastructure is that
- * the KICK handlers require access to a CPU's pTBI structure. So we
- * pass it as an argument.
- */
-#include <linux/export.h>
-#include <linux/hardirq.h>
-#include <linux/irq.h>
-#include <linux/kernel.h>
-#include <linux/mm.h>
-#include <linux/types.h>
-
-#include <asm/traps.h>
-
-/*
- * All accesses/manipulations of kick_handlers_list should be
- * performed while holding kick_handlers_lock.
- */
-static DEFINE_SPINLOCK(kick_handlers_lock);
-static LIST_HEAD(kick_handlers_list);
-
-void kick_register_func(struct kick_irq_handler *kh)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&kick_handlers_lock, flags);
-
- list_add_tail(&kh->list, &kick_handlers_list);
-
- spin_unlock_irqrestore(&kick_handlers_lock, flags);
-}
-EXPORT_SYMBOL(kick_register_func);
-
-void kick_unregister_func(struct kick_irq_handler *kh)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&kick_handlers_lock, flags);
-
- list_del(&kh->list);
-
- spin_unlock_irqrestore(&kick_handlers_lock, flags);
-}
-EXPORT_SYMBOL(kick_unregister_func);
-
-TBIRES
-kick_handler(TBIRES State, int SigNum, int Triggers, int Inst, PTBI pTBI)
-{
- struct pt_regs *old_regs;
- struct kick_irq_handler *kh;
- struct list_head *lh;
- int handled = 0;
- TBIRES ret;
-
- head_end(State, ~INTS_OFF_MASK);
-
- /* If we interrupted user code handle any critical sections. */
- if (State.Sig.SaveMask & TBICTX_PRIV_BIT)
- restart_critical_section(State);
-
- trace_hardirqs_off();
-
- old_regs = set_irq_regs((struct pt_regs *)State.Sig.pCtx);
- irq_enter();
-
- /*
- * There is no need to disable interrupts here because we
- * can't nest KICK interrupts in a KICK interrupt handler.
- */
- spin_lock(&kick_handlers_lock);
-
- list_for_each(lh, &kick_handlers_list) {
- kh = list_entry(lh, struct kick_irq_handler, list);
-
- ret = kh->func(State, SigNum, Triggers, Inst, pTBI, &handled);
- if (handled)
- break;
- }
-
- spin_unlock(&kick_handlers_lock);
-
- WARN_ON(!handled);
-
- irq_exit();
- set_irq_regs(old_regs);
-
- return tail_end(ret);
-}
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