Skip to content
Snippets Groups Projects
system.h 6.27 KiB
Newer Older
  • Learn to ignore specific revisions
  • /*
     * 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.
     *
     * Copyright (C) 1994 - 1999 by Ralf Baechle
     * Copyright (C) 1996 by Paul M. Antoine
     * Copyright (C) 1994 - 1999 by Ralf Baechle
     *
     * Changed set_except_vector declaration to allow return of previous
    
    Wolfgang Denk's avatar
    Wolfgang Denk committed
     * vector address value - necessary for "borrowing" vectors.
    
     *
     * Kevin D. Kissell, kevink@mips.org and Carsten Langgaard, carstenl@mips.com
     * Copyright (C) 2000 MIPS Technologies, Inc.
     */
    #ifndef _ASM_SYSTEM_H
    #define _ASM_SYSTEM_H
    
    #include <asm/sgidefs.h>
    #include <asm/ptrace.h>
    #if 0
    #include <linux/kernel.h>
    #endif
    
    
    static __inline__ void
    
    __sti(void)
    {
    	__asm__ __volatile__(
    		".set\tpush\n\t"
    		".set\treorder\n\t"
    		".set\tnoat\n\t"
    		"mfc0\t$1,$12\n\t"
    		"ori\t$1,0x1f\n\t"
    		"xori\t$1,0x1e\n\t"
    		"mtc0\t$1,$12\n\t"
    		".set\tpop\n\t"
    		: /* no outputs */
    		: /* no inputs */
    		: "$1", "memory");
    }
    
    /*
     * For cli() we have to insert nops to make shure that the new value
     * has actually arrived in the status register before the end of this
     * macro.
     * R4000/R4400 need three nops, the R4600 two nops and the R10000 needs
     * no nops at all.
     */
    
    static __inline__ void
    
    __cli(void)
    {
    	__asm__ __volatile__(
    		".set\tpush\n\t"
    		".set\treorder\n\t"
    		".set\tnoat\n\t"
    		"mfc0\t$1,$12\n\t"
    		"ori\t$1,1\n\t"
    		"xori\t$1,1\n\t"
    		".set\tnoreorder\n\t"
    		"mtc0\t$1,$12\n\t"
    		"nop\n\t"
    		"nop\n\t"
    		"nop\n\t"
    		".set\tpop\n\t"
    		: /* no outputs */
    		: /* no inputs */
    		: "$1", "memory");
    }
    
    #define __save_flags(x)							\
    __asm__ __volatile__(							\
    	".set\tpush\n\t"						\
    	".set\treorder\n\t"						\
    	"mfc0\t%0,$12\n\t"						\
    	".set\tpop\n\t"							\
    	: "=r" (x))
    
    #define __save_and_cli(x)						\
    __asm__ __volatile__(							\
    	".set\tpush\n\t"						\
    	".set\treorder\n\t"						\
    	".set\tnoat\n\t"						\
    	"mfc0\t%0,$12\n\t"						\
    	"ori\t$1,%0,1\n\t"						\
    	"xori\t$1,1\n\t"						\
    	".set\tnoreorder\n\t"						\
    	"mtc0\t$1,$12\n\t"						\
    	"nop\n\t"							\
    	"nop\n\t"							\
    	"nop\n\t"							\
    	".set\tpop\n\t"							\
    	: "=r" (x)							\
    	: /* no inputs */						\
    	: "$1", "memory")
    
    #define __restore_flags(flags)						\
    do {									\
    	unsigned long __tmp1;						\
    									\
    	__asm__ __volatile__(						\
    		".set\tnoreorder\t\t\t# __restore_flags\n\t"		\
    		".set\tnoat\n\t"					\
    		"mfc0\t$1, $12\n\t"					\
    		"andi\t%0, 1\n\t"					\
    		"ori\t$1, 1\n\t"					\
    		"xori\t$1, 1\n\t"					\
    		"or\t%0, $1\n\t"					\
    		"mtc0\t%0, $12\n\t"					\
    		"nop\n\t"						\
    		"nop\n\t"						\
    		"nop\n\t"						\
    		".set\tat\n\t"						\
    		".set\treorder"						\
    		: "=r" (__tmp1)						\
    		: "0" (flags)						\
    		: "$1", "memory");					\
    } while(0)
    
    #ifdef CONFIG_SMP
    
    extern void __global_sti(void);
    extern void __global_cli(void);
    extern unsigned long __global_save_flags(void);
    extern void __global_restore_flags(unsigned long);
    #  define sti() __global_sti()
    
    Wolfgang Denk's avatar
    Wolfgang Denk committed
    #  define cli() __global_cli()
    
    #  define save_flags(x) do { x = __global_save_flags(); } while (0)
    #  define restore_flags(x) __global_restore_flags(x)
    #  define save_and_cli(x) do { save_flags(x); cli(); } while(0)
    
    #else /* Single processor */
    
    #  define sti() __sti()
    #  define cli() __cli()
    #  define save_flags(x) __save_flags(x)
    #  define save_and_cli(x) __save_and_cli(x)
    #  define restore_flags(x) __restore_flags(x)
    
    #endif /* SMP */
    
    /* For spinlocks etc */
    #define local_irq_save(x)	__save_and_cli(x);
    #define local_irq_restore(x)	__restore_flags(x);
    #define local_irq_disable()	__cli();
    #define local_irq_enable()	__sti();
    
    /*
     * These are probably defined overly paranoid ...
     */
    #ifdef CONFIG_CPU_HAS_WB
    
    #include <asm/wbflush.h>
    #define rmb()	do { } while(0)
    #define wmb()	wbflush()
    #define mb()	wbflush()
    
    #else /* CONFIG_CPU_HAS_WB  */
    
    #define mb()						\
    __asm__ __volatile__(					\
    	"# prevent instructions being moved around\n\t"	\
    	".set\tnoreorder\n\t"				\
    	"# 8 nops to fool the R4400 pipeline\n\t"	\
    	"nop;nop;nop;nop;nop;nop;nop;nop\n\t"		\
    	".set\treorder"					\
    	: /* no output */				\
    	: /* no input */				\
    	: "memory")
    #define rmb() mb()
    #define wmb() mb()
    
    #endif /* CONFIG_CPU_HAS_WB  */
    
    #ifdef CONFIG_SMP
    #define smp_mb()	mb()
    #define smp_rmb()	rmb()
    #define smp_wmb()	wmb()
    #else
    #define smp_mb()	barrier()
    #define smp_rmb()	barrier()
    #define smp_wmb()	barrier()
    #endif
    
    #define set_mb(var, value) \
    do { var = value; mb(); } while (0)
    
    #define set_wmb(var, value) \
    do { var = value; wmb(); } while (0)
    
    #if !defined (_LANGUAGE_ASSEMBLY)
    /*
     * switch_to(n) should switch tasks to task nr n, first
     * checking that n isn't the current task, in which case it does nothing.
     */
    #if 0
    extern asmlinkage void *resume(void *last, void *next);
    #endif
    #endif /* !defined (_LANGUAGE_ASSEMBLY) */
    
    #define prepare_to_switch()	do { } while(0)
    #define switch_to(prev,next,last) \
    do { \
    	(last) = resume(prev, next); \
    } while(0)
    
    /*
     * For 32 and 64 bit operands we can take advantage of ll and sc.
     * FIXME: This doesn't work for R3000 machines.
     */
    
    static __inline__ unsigned long xchg_u32(volatile int * m, unsigned long val)
    
    {
    #ifdef CONFIG_CPU_HAS_LLSC
    	unsigned long dummy;
    
    	__asm__ __volatile__(
    		".set\tnoreorder\t\t\t# xchg_u32\n\t"
    		".set\tnoat\n\t"
    		"ll\t%0, %3\n"
    		"1:\tmove\t$1, %2\n\t"
    		"sc\t$1, %1\n\t"
    		"beqzl\t$1, 1b\n\t"
    		" ll\t%0, %3\n\t"
    		".set\tat\n\t"
    		".set\treorder"
    		: "=r" (val), "=o" (*m), "=r" (dummy)
    		: "o" (*m), "2" (val)
    		: "memory");
    
    	return val;
    #else
    	unsigned long flags, retval;
    
    	save_flags(flags);
    	cli();
    	retval = *m;
    	*m = val;
    	restore_flags(flags);
    	return retval;
    #endif /* Processor-dependent optimization */
    }
    
    #define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
    #define tas(ptr) (xchg((ptr),1))
    
    static __inline__ unsigned long
    __xchg(unsigned long x, volatile void * ptr, int size)
    {
    	switch (size) {
    		case 4:
    			return xchg_u32(ptr, x);
    	}
    	return x;
    }
    
    extern void *set_except_vector(int n, void *addr);
    
    extern void __die(const char *, struct pt_regs *, const char *where,
    	unsigned long line) __attribute__((noreturn));
    extern void __die_if_kernel(const char *, struct pt_regs *, const char *where,
    	unsigned long line);
    
    #define die(msg, regs)							\
    	__die(msg, regs, __FILE__ ":"__FUNCTION__, __LINE__)
    #define die_if_kernel(msg, regs)					\
    	__die_if_kernel(msg, regs, __FILE__ ":"__FUNCTION__, __LINE__)
    
    #endif /* _ASM_SYSTEM_H */