initial_commit

1 files changed, 102 insertions, 0 deletions

diff --git a/arch/mn10300/include/asm/system.h b/arch/mn10300/include/asm/system.h
new file mode 100644
index 00000000..8ff3e5aa
--- /dev/null
+++ b/arch/mn10300/include/asm/system.h
@@ -0,0 +1,102 @@
+/* MN10300 System definitions
+ *
+ * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+#ifndef _ASM_SYSTEM_H
+#define _ASM_SYSTEM_H
+
+#include <asm/cpu-regs.h>
+#include <asm/intctl-regs.h>
+
+#ifdef __KERNEL__
+#ifndef __ASSEMBLY__
+
+#include <linux/kernel.h>
+#include <linux/irqflags.h>
+#include <asm/atomic.h>
+
+#if !defined(CONFIG_LAZY_SAVE_FPU)
+struct fpu_state_struct;
+extern asmlinkage void fpu_save(struct fpu_state_struct *);
+#define switch_fpu(prev, next)						\
+	do {								\
+		if ((prev)->thread.fpu_flags & THREAD_HAS_FPU) {	\
+			(prev)->thread.fpu_flags &= ~THREAD_HAS_FPU;	\
+			(prev)->thread.uregs->epsw &= ~EPSW_FE;		\
+			fpu_save(&(prev)->thread.fpu_state);		\
+		}							\
+	} while (0)
+#else
+#define switch_fpu(prev, next) do {} while (0)
+#endif
+
+struct task_struct;
+struct thread_struct;
+
+extern asmlinkage
+struct task_struct *__switch_to(struct thread_struct *prev,
+				struct thread_struct *next,
+				struct task_struct *prev_task);
+
+/* context switching is now performed out-of-line in switch_to.S */
+#define switch_to(prev, next, last)					\
+do {									\
+	switch_fpu(prev, next);						\
+	current->thread.wchan = (u_long) __builtin_return_address(0);	\
+	(last) = __switch_to(&(prev)->thread, &(next)->thread, (prev));	\
+	mb();								\
+	current->thread.wchan = 0;					\
+} while (0)
+
+#define arch_align_stack(x) (x)
+
+#define nop() asm volatile ("nop")
+
+/*
+ * Force strict CPU ordering.
+ * And yes, this is required on UP too when we're talking
+ * to devices.
+ *
+ * For now, "wmb()" doesn't actually do anything, as all
+ * Intel CPU's follow what Intel calls a *Processor Order*,
+ * in which all writes are seen in the program order even
+ * outside the CPU.
+ *
+ * I expect future Intel CPU's to have a weaker ordering,
+ * but I'd also expect them to finally get their act together
+ * and add some real memory barriers if so.
+ *
+ * Some non intel clones support out of order store. wmb() ceases to be a
+ * nop for these.
+ */
+
+#define mb()	asm volatile ("": : :"memory")
+#define rmb()	mb()
+#define wmb()	asm volatile ("": : :"memory")
+
+#ifdef CONFIG_SMP
+#define smp_mb()	mb()
+#define smp_rmb()	rmb()
+#define smp_wmb()	wmb()
+#define set_mb(var, value)  do { xchg(&var, value); } while (0)
+#else  /* CONFIG_SMP */
+#define smp_mb()	barrier()
+#define smp_rmb()	barrier()
+#define smp_wmb()	barrier()
+#define set_mb(var, value)  do { var = value;  mb(); } while (0)
+#endif /* CONFIG_SMP */
+
+#define set_wmb(var, value) do { var = value; wmb(); } while (0)
+
+#define read_barrier_depends()		do {} while (0)
+#define smp_read_barrier_depends()	do {} while (0)
+
+#endif /* !__ASSEMBLY__ */
+#endif /* __KERNEL__ */
+#endif /* _ASM_SYSTEM_H */