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- /* $Id: system.h,v 1.8 1998/07/20 17:52:21 ralf Exp $
- *
- * 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, 1995, 1996, 1997, 1998 by Ralf Baechle
- * Modified further for R[236]000 by Paul M. Antoine, 1996
- */
- #ifndef __ASM_MIPS_SYSTEM_H
- #define __ASM_MIPS_SYSTEM_H
-
- #include <asm/sgidefs.h>
- #include <linux/kernel.h>
-
- extern __inline__ void
- __sti(void)
- {
- __asm__ __volatile__(
- ".set\tnoreorder\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\tat\n\t"
- ".set\treorder"
- : /* 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.
- */
- extern __inline__ void
- __cli(void)
- {
- __asm__ __volatile__(
- ".set\tnoreorder\n\t"
- ".set\tnoat\n\t"
- "mfc0\t$1,$12\n\t"
- "ori\t$1,1\n\t"
- "xori\t$1,1\n\t"
- "mtc0\t$1,$12\n\t"
- "nop\n\t"
- "nop\n\t"
- "nop\n\t"
- ".set\tat\n\t"
- ".set\treorder"
- : /* no outputs */
- : /* no inputs */
- : "$1", "memory");
- }
-
- #define __save_flags(x) \
- __asm__ __volatile__( \
- ".set\tnoreorder\n\t" \
- "mfc0\t%0,$12\n\t" \
- ".set\treorder" \
- : "=r" (x) \
- : /* no inputs */ \
- : "memory")
-
- #define __save_and_cli(x) \
- __asm__ __volatile__( \
- ".set\tnoreorder\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" \
- "mtc0\t$1,$12\n\t" \
- "nop\n\t" \
- "nop\n\t" \
- "nop\n\t" \
- ".set\tat\n\t" \
- ".set\treorder" \
- : "=r" (x) \
- : /* no inputs */ \
- : "$1", "memory")
-
- extern void __inline__
- __restore_flags(int flags)
- {
- __asm__ __volatile__(
- ".set\tnoreorder\n\t"
- "mtc0\t%0,$12\n\t"
- "nop\n\t"
- "nop\n\t"
- "nop\n\t"
- ".set\treorder"
- : /* no output */
- : "r" (flags)
- : "memory");
- }
-
- /*
- * Non-SMP versions ...
- */
- #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)
-
- #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")
-
- #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.
- */
- extern asmlinkage void (*resume)(void *tsk);
- #endif /* !defined (_LANGUAGE_ASSEMBLY) */
-
- #define switch_to(prev,next) \
- do { \
- resume(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.
- */
- extern __inline__ unsigned long xchg_u32(volatile int * m, unsigned long val)
- {
- #if (_MIPS_ISA == _MIPS_ISA_MIPS2) || (_MIPS_ISA == _MIPS_ISA_MIPS3) || \
- (_MIPS_ISA == _MIPS_ISA_MIPS4) || (_MIPS_ISA == _MIPS_ISA_MIPS5)
- unsigned long dummy;
-
- __asm__ __volatile__(
- ".set\tnoreorder\n\t"
- ".set\tnoat\n\t"
- "ll\t%0,(%1)\n"
- "1:\tmove\t$1,%2\n\t"
- "sc\t$1,(%1)\n\t"
- "beqzl\t$1,1b\n\t"
- "ll\t%0,(%1)\n\t"
- ".set\tat\n\t"
- ".set\treorder"
- : "=r" (val), "=r" (m), "=r" (dummy)
- : "1" (m), "2" (val)
- : "memory");
- #else
- unsigned long flags, retval;
-
- save_flags(flags);
- cli();
- retval = *m;
- *m = val;
- restore_flags(flags);
-
- #endif /* Processor-dependent optimization */
- return val;
- }
-
- /*
- * Only used for 64 bit kernel.
- */
- extern __inline__ unsigned long xchg_u64(volatile long * m, unsigned long val)
- {
- unsigned long dummy;
-
- __asm__ __volatile__(
- ".set\tnoreorder\n\t"
- ".set\tnoat\n\t"
- "lld\t%0,(%1)\n"
- "1:\tmove\t$1,%2\n\t"
- "scd\t$1,(%1)\n\t"
- "beqzl\t$1,1b\n\t"
- "ll\t%0,(%1)\n\t"
- ".set\tat\n\t"
- ".set\treorder"
- : "=r" (val), "=r" (m), "=r" (dummy)
- : "1" (m), "2" (val)
- : "memory");
-
- return val;
- }
-
- #define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
- #define tas(ptr) (xchg((ptr),1))
-
- /*
- * This function doesn't exist, so you'll get a linker error
- * if something tries to do an invalid xchg().
- *
- * This only works if the compiler isn't horribly bad at optimizing.
- * gcc-2.5.8 reportedly can't handle this, but I define that one to
- * be dead anyway.
- */
- extern void __xchg_called_with_bad_pointer(void);
-
- static __inline__ unsigned long __xchg(unsigned long x, volatile void * ptr, int size)
- {
- switch (size) {
- case 4:
- return xchg_u32(ptr, x);
- #if defined(__mips64)
- case 8:
- return xchg_u64(ptr, x);
- #endif
- }
- __xchg_called_with_bad_pointer();
- return x;
- }
-
- extern void set_except_vector(int n, void *addr);
-
- #endif /* __ASM_MIPS_SYSTEM_H */
-