563 строки
16 KiB
C
563 строки
16 KiB
C
#ifndef __ASM_SYSTEM_H
|
|
#define __ASM_SYSTEM_H
|
|
|
|
#include <linux/config.h>
|
|
#include <linux/kernel.h>
|
|
#include <asm/segment.h>
|
|
#include <asm/cpufeature.h>
|
|
#include <linux/bitops.h> /* for LOCK_PREFIX */
|
|
|
|
#ifdef __KERNEL__
|
|
|
|
struct task_struct; /* one of the stranger aspects of C forward declarations.. */
|
|
extern struct task_struct * FASTCALL(__switch_to(struct task_struct *prev, struct task_struct *next));
|
|
|
|
#define switch_to(prev,next,last) do { \
|
|
unsigned long esi,edi; \
|
|
asm volatile("pushl %%ebp\n\t" \
|
|
"movl %%esp,%0\n\t" /* save ESP */ \
|
|
"movl %5,%%esp\n\t" /* restore ESP */ \
|
|
"movl $1f,%1\n\t" /* save EIP */ \
|
|
"pushl %6\n\t" /* restore EIP */ \
|
|
"jmp __switch_to\n" \
|
|
"1:\t" \
|
|
"popl %%ebp\n\t" \
|
|
:"=m" (prev->thread.esp),"=m" (prev->thread.eip), \
|
|
"=a" (last),"=S" (esi),"=D" (edi) \
|
|
:"m" (next->thread.esp),"m" (next->thread.eip), \
|
|
"2" (prev), "d" (next)); \
|
|
} while (0)
|
|
|
|
#define _set_base(addr,base) do { unsigned long __pr; \
|
|
__asm__ __volatile__ ("movw %%dx,%1\n\t" \
|
|
"rorl $16,%%edx\n\t" \
|
|
"movb %%dl,%2\n\t" \
|
|
"movb %%dh,%3" \
|
|
:"=&d" (__pr) \
|
|
:"m" (*((addr)+2)), \
|
|
"m" (*((addr)+4)), \
|
|
"m" (*((addr)+7)), \
|
|
"0" (base) \
|
|
); } while(0)
|
|
|
|
#define _set_limit(addr,limit) do { unsigned long __lr; \
|
|
__asm__ __volatile__ ("movw %%dx,%1\n\t" \
|
|
"rorl $16,%%edx\n\t" \
|
|
"movb %2,%%dh\n\t" \
|
|
"andb $0xf0,%%dh\n\t" \
|
|
"orb %%dh,%%dl\n\t" \
|
|
"movb %%dl,%2" \
|
|
:"=&d" (__lr) \
|
|
:"m" (*(addr)), \
|
|
"m" (*((addr)+6)), \
|
|
"0" (limit) \
|
|
); } while(0)
|
|
|
|
#define set_base(ldt,base) _set_base( ((char *)&(ldt)) , (base) )
|
|
#define set_limit(ldt,limit) _set_limit( ((char *)&(ldt)) , ((limit)-1) )
|
|
|
|
/*
|
|
* Load a segment. Fall back on loading the zero
|
|
* segment if something goes wrong..
|
|
*/
|
|
#define loadsegment(seg,value) \
|
|
asm volatile("\n" \
|
|
"1:\t" \
|
|
"mov %0,%%" #seg "\n" \
|
|
"2:\n" \
|
|
".section .fixup,\"ax\"\n" \
|
|
"3:\t" \
|
|
"pushl $0\n\t" \
|
|
"popl %%" #seg "\n\t" \
|
|
"jmp 2b\n" \
|
|
".previous\n" \
|
|
".section __ex_table,\"a\"\n\t" \
|
|
".align 4\n\t" \
|
|
".long 1b,3b\n" \
|
|
".previous" \
|
|
: :"rm" (value))
|
|
|
|
/*
|
|
* Save a segment register away
|
|
*/
|
|
#define savesegment(seg, value) \
|
|
asm volatile("mov %%" #seg ",%0":"=rm" (value))
|
|
|
|
/*
|
|
* Clear and set 'TS' bit respectively
|
|
*/
|
|
#define clts() __asm__ __volatile__ ("clts")
|
|
#define read_cr0() ({ \
|
|
unsigned int __dummy; \
|
|
__asm__ __volatile__( \
|
|
"movl %%cr0,%0\n\t" \
|
|
:"=r" (__dummy)); \
|
|
__dummy; \
|
|
})
|
|
#define write_cr0(x) \
|
|
__asm__ __volatile__("movl %0,%%cr0": :"r" (x));
|
|
|
|
#define read_cr2() ({ \
|
|
unsigned int __dummy; \
|
|
__asm__ __volatile__( \
|
|
"movl %%cr2,%0\n\t" \
|
|
:"=r" (__dummy)); \
|
|
__dummy; \
|
|
})
|
|
#define write_cr2(x) \
|
|
__asm__ __volatile__("movl %0,%%cr2": :"r" (x));
|
|
|
|
#define read_cr3() ({ \
|
|
unsigned int __dummy; \
|
|
__asm__ ( \
|
|
"movl %%cr3,%0\n\t" \
|
|
:"=r" (__dummy)); \
|
|
__dummy; \
|
|
})
|
|
#define write_cr3(x) \
|
|
__asm__ __volatile__("movl %0,%%cr3": :"r" (x));
|
|
|
|
#define read_cr4() ({ \
|
|
unsigned int __dummy; \
|
|
__asm__( \
|
|
"movl %%cr4,%0\n\t" \
|
|
:"=r" (__dummy)); \
|
|
__dummy; \
|
|
})
|
|
|
|
#define read_cr4_safe() ({ \
|
|
unsigned int __dummy; \
|
|
/* This could fault if %cr4 does not exist */ \
|
|
__asm__("1: movl %%cr4, %0 \n" \
|
|
"2: \n" \
|
|
".section __ex_table,\"a\" \n" \
|
|
".long 1b,2b \n" \
|
|
".previous \n" \
|
|
: "=r" (__dummy): "0" (0)); \
|
|
__dummy; \
|
|
})
|
|
|
|
#define write_cr4(x) \
|
|
__asm__ __volatile__("movl %0,%%cr4": :"r" (x));
|
|
#define stts() write_cr0(8 | read_cr0())
|
|
|
|
#endif /* __KERNEL__ */
|
|
|
|
#define wbinvd() \
|
|
__asm__ __volatile__ ("wbinvd": : :"memory");
|
|
|
|
static inline unsigned long get_limit(unsigned long segment)
|
|
{
|
|
unsigned long __limit;
|
|
__asm__("lsll %1,%0"
|
|
:"=r" (__limit):"r" (segment));
|
|
return __limit+1;
|
|
}
|
|
|
|
#define nop() __asm__ __volatile__ ("nop")
|
|
|
|
#define xchg(ptr,v) ((__typeof__(*(ptr)))__xchg((unsigned long)(v),(ptr),sizeof(*(ptr))))
|
|
|
|
#define tas(ptr) (xchg((ptr),1))
|
|
|
|
struct __xchg_dummy { unsigned long a[100]; };
|
|
#define __xg(x) ((struct __xchg_dummy *)(x))
|
|
|
|
|
|
#ifdef CONFIG_X86_CMPXCHG64
|
|
|
|
/*
|
|
* The semantics of XCHGCMP8B are a bit strange, this is why
|
|
* there is a loop and the loading of %%eax and %%edx has to
|
|
* be inside. This inlines well in most cases, the cached
|
|
* cost is around ~38 cycles. (in the future we might want
|
|
* to do an SIMD/3DNOW!/MMX/FPU 64-bit store here, but that
|
|
* might have an implicit FPU-save as a cost, so it's not
|
|
* clear which path to go.)
|
|
*
|
|
* cmpxchg8b must be used with the lock prefix here to allow
|
|
* the instruction to be executed atomically, see page 3-102
|
|
* of the instruction set reference 24319102.pdf. We need
|
|
* the reader side to see the coherent 64bit value.
|
|
*/
|
|
static inline void __set_64bit (unsigned long long * ptr,
|
|
unsigned int low, unsigned int high)
|
|
{
|
|
__asm__ __volatile__ (
|
|
"\n1:\t"
|
|
"movl (%0), %%eax\n\t"
|
|
"movl 4(%0), %%edx\n\t"
|
|
"lock cmpxchg8b (%0)\n\t"
|
|
"jnz 1b"
|
|
: /* no outputs */
|
|
: "D"(ptr),
|
|
"b"(low),
|
|
"c"(high)
|
|
: "ax","dx","memory");
|
|
}
|
|
|
|
static inline void __set_64bit_constant (unsigned long long *ptr,
|
|
unsigned long long value)
|
|
{
|
|
__set_64bit(ptr,(unsigned int)(value), (unsigned int)((value)>>32ULL));
|
|
}
|
|
#define ll_low(x) *(((unsigned int*)&(x))+0)
|
|
#define ll_high(x) *(((unsigned int*)&(x))+1)
|
|
|
|
static inline void __set_64bit_var (unsigned long long *ptr,
|
|
unsigned long long value)
|
|
{
|
|
__set_64bit(ptr,ll_low(value), ll_high(value));
|
|
}
|
|
|
|
#define set_64bit(ptr,value) \
|
|
(__builtin_constant_p(value) ? \
|
|
__set_64bit_constant(ptr, value) : \
|
|
__set_64bit_var(ptr, value) )
|
|
|
|
#define _set_64bit(ptr,value) \
|
|
(__builtin_constant_p(value) ? \
|
|
__set_64bit(ptr, (unsigned int)(value), (unsigned int)((value)>>32ULL) ) : \
|
|
__set_64bit(ptr, ll_low(value), ll_high(value)) )
|
|
|
|
#endif
|
|
|
|
/*
|
|
* Note: no "lock" prefix even on SMP: xchg always implies lock anyway
|
|
* Note 2: xchg has side effect, so that attribute volatile is necessary,
|
|
* but generally the primitive is invalid, *ptr is output argument. --ANK
|
|
*/
|
|
static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size)
|
|
{
|
|
switch (size) {
|
|
case 1:
|
|
__asm__ __volatile__("xchgb %b0,%1"
|
|
:"=q" (x)
|
|
:"m" (*__xg(ptr)), "0" (x)
|
|
:"memory");
|
|
break;
|
|
case 2:
|
|
__asm__ __volatile__("xchgw %w0,%1"
|
|
:"=r" (x)
|
|
:"m" (*__xg(ptr)), "0" (x)
|
|
:"memory");
|
|
break;
|
|
case 4:
|
|
__asm__ __volatile__("xchgl %0,%1"
|
|
:"=r" (x)
|
|
:"m" (*__xg(ptr)), "0" (x)
|
|
:"memory");
|
|
break;
|
|
}
|
|
return x;
|
|
}
|
|
|
|
/*
|
|
* Atomic compare and exchange. Compare OLD with MEM, if identical,
|
|
* store NEW in MEM. Return the initial value in MEM. Success is
|
|
* indicated by comparing RETURN with OLD.
|
|
*/
|
|
|
|
#ifdef CONFIG_X86_CMPXCHG
|
|
#define __HAVE_ARCH_CMPXCHG 1
|
|
#define cmpxchg(ptr,o,n)\
|
|
((__typeof__(*(ptr)))__cmpxchg((ptr),(unsigned long)(o),\
|
|
(unsigned long)(n),sizeof(*(ptr))))
|
|
#endif
|
|
|
|
static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
|
|
unsigned long new, int size)
|
|
{
|
|
unsigned long prev;
|
|
switch (size) {
|
|
case 1:
|
|
__asm__ __volatile__(LOCK_PREFIX "cmpxchgb %b1,%2"
|
|
: "=a"(prev)
|
|
: "q"(new), "m"(*__xg(ptr)), "0"(old)
|
|
: "memory");
|
|
return prev;
|
|
case 2:
|
|
__asm__ __volatile__(LOCK_PREFIX "cmpxchgw %w1,%2"
|
|
: "=a"(prev)
|
|
: "r"(new), "m"(*__xg(ptr)), "0"(old)
|
|
: "memory");
|
|
return prev;
|
|
case 4:
|
|
__asm__ __volatile__(LOCK_PREFIX "cmpxchgl %1,%2"
|
|
: "=a"(prev)
|
|
: "r"(new), "m"(*__xg(ptr)), "0"(old)
|
|
: "memory");
|
|
return prev;
|
|
}
|
|
return old;
|
|
}
|
|
|
|
#ifndef CONFIG_X86_CMPXCHG
|
|
/*
|
|
* Building a kernel capable running on 80386. It may be necessary to
|
|
* simulate the cmpxchg on the 80386 CPU. For that purpose we define
|
|
* a function for each of the sizes we support.
|
|
*/
|
|
|
|
extern unsigned long cmpxchg_386_u8(volatile void *, u8, u8);
|
|
extern unsigned long cmpxchg_386_u16(volatile void *, u16, u16);
|
|
extern unsigned long cmpxchg_386_u32(volatile void *, u32, u32);
|
|
|
|
static inline unsigned long cmpxchg_386(volatile void *ptr, unsigned long old,
|
|
unsigned long new, int size)
|
|
{
|
|
switch (size) {
|
|
case 1:
|
|
return cmpxchg_386_u8(ptr, old, new);
|
|
case 2:
|
|
return cmpxchg_386_u16(ptr, old, new);
|
|
case 4:
|
|
return cmpxchg_386_u32(ptr, old, new);
|
|
}
|
|
return old;
|
|
}
|
|
|
|
#define cmpxchg(ptr,o,n) \
|
|
({ \
|
|
__typeof__(*(ptr)) __ret; \
|
|
if (likely(boot_cpu_data.x86 > 3)) \
|
|
__ret = __cmpxchg((ptr), (unsigned long)(o), \
|
|
(unsigned long)(n), sizeof(*(ptr))); \
|
|
else \
|
|
__ret = cmpxchg_386((ptr), (unsigned long)(o), \
|
|
(unsigned long)(n), sizeof(*(ptr))); \
|
|
__ret; \
|
|
})
|
|
#endif
|
|
|
|
#ifdef CONFIG_X86_CMPXCHG64
|
|
|
|
static inline unsigned long long __cmpxchg64(volatile void *ptr, unsigned long long old,
|
|
unsigned long long new)
|
|
{
|
|
unsigned long long prev;
|
|
__asm__ __volatile__(LOCK_PREFIX "cmpxchg8b %3"
|
|
: "=A"(prev)
|
|
: "b"((unsigned long)new),
|
|
"c"((unsigned long)(new >> 32)),
|
|
"m"(*__xg(ptr)),
|
|
"0"(old)
|
|
: "memory");
|
|
return prev;
|
|
}
|
|
|
|
#define cmpxchg64(ptr,o,n)\
|
|
((__typeof__(*(ptr)))__cmpxchg64((ptr),(unsigned long long)(o),\
|
|
(unsigned long long)(n)))
|
|
|
|
#endif
|
|
|
|
#ifdef __KERNEL__
|
|
struct alt_instr {
|
|
__u8 *instr; /* original instruction */
|
|
__u8 *replacement;
|
|
__u8 cpuid; /* cpuid bit set for replacement */
|
|
__u8 instrlen; /* length of original instruction */
|
|
__u8 replacementlen; /* length of new instruction, <= instrlen */
|
|
__u8 pad;
|
|
};
|
|
#endif
|
|
|
|
/*
|
|
* Alternative instructions for different CPU types or capabilities.
|
|
*
|
|
* This allows to use optimized instructions even on generic binary
|
|
* kernels.
|
|
*
|
|
* length of oldinstr must be longer or equal the length of newinstr
|
|
* It can be padded with nops as needed.
|
|
*
|
|
* For non barrier like inlines please define new variants
|
|
* without volatile and memory clobber.
|
|
*/
|
|
#define alternative(oldinstr, newinstr, feature) \
|
|
asm volatile ("661:\n\t" oldinstr "\n662:\n" \
|
|
".section .altinstructions,\"a\"\n" \
|
|
" .align 4\n" \
|
|
" .long 661b\n" /* label */ \
|
|
" .long 663f\n" /* new instruction */ \
|
|
" .byte %c0\n" /* feature bit */ \
|
|
" .byte 662b-661b\n" /* sourcelen */ \
|
|
" .byte 664f-663f\n" /* replacementlen */ \
|
|
".previous\n" \
|
|
".section .altinstr_replacement,\"ax\"\n" \
|
|
"663:\n\t" newinstr "\n664:\n" /* replacement */ \
|
|
".previous" :: "i" (feature) : "memory")
|
|
|
|
/*
|
|
* Alternative inline assembly with input.
|
|
*
|
|
* Pecularities:
|
|
* No memory clobber here.
|
|
* Argument numbers start with 1.
|
|
* Best is to use constraints that are fixed size (like (%1) ... "r")
|
|
* If you use variable sized constraints like "m" or "g" in the
|
|
* replacement maake sure to pad to the worst case length.
|
|
*/
|
|
#define alternative_input(oldinstr, newinstr, feature, input...) \
|
|
asm volatile ("661:\n\t" oldinstr "\n662:\n" \
|
|
".section .altinstructions,\"a\"\n" \
|
|
" .align 4\n" \
|
|
" .long 661b\n" /* label */ \
|
|
" .long 663f\n" /* new instruction */ \
|
|
" .byte %c0\n" /* feature bit */ \
|
|
" .byte 662b-661b\n" /* sourcelen */ \
|
|
" .byte 664f-663f\n" /* replacementlen */ \
|
|
".previous\n" \
|
|
".section .altinstr_replacement,\"ax\"\n" \
|
|
"663:\n\t" newinstr "\n664:\n" /* replacement */ \
|
|
".previous" :: "i" (feature), ##input)
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
|
|
|
|
/*
|
|
* Actually only lfence would be needed for mb() because all stores done
|
|
* by the kernel should be already ordered. But keep a full barrier for now.
|
|
*/
|
|
|
|
#define mb() alternative("lock; addl $0,0(%%esp)", "mfence", X86_FEATURE_XMM2)
|
|
#define rmb() alternative("lock; addl $0,0(%%esp)", "lfence", X86_FEATURE_XMM2)
|
|
|
|
/**
|
|
* read_barrier_depends - Flush all pending reads that subsequents reads
|
|
* depend on.
|
|
*
|
|
* No data-dependent reads from memory-like regions are ever reordered
|
|
* over this barrier. All reads preceding this primitive are guaranteed
|
|
* to access memory (but not necessarily other CPUs' caches) before any
|
|
* reads following this primitive that depend on the data return by
|
|
* any of the preceding reads. This primitive is much lighter weight than
|
|
* rmb() on most CPUs, and is never heavier weight than is
|
|
* rmb().
|
|
*
|
|
* These ordering constraints are respected by both the local CPU
|
|
* and the compiler.
|
|
*
|
|
* Ordering is not guaranteed by anything other than these primitives,
|
|
* not even by data dependencies. See the documentation for
|
|
* memory_barrier() for examples and URLs to more information.
|
|
*
|
|
* For example, the following code would force ordering (the initial
|
|
* value of "a" is zero, "b" is one, and "p" is "&a"):
|
|
*
|
|
* <programlisting>
|
|
* CPU 0 CPU 1
|
|
*
|
|
* b = 2;
|
|
* memory_barrier();
|
|
* p = &b; q = p;
|
|
* read_barrier_depends();
|
|
* d = *q;
|
|
* </programlisting>
|
|
*
|
|
* because the read of "*q" depends on the read of "p" and these
|
|
* two reads are separated by a read_barrier_depends(). However,
|
|
* the following code, with the same initial values for "a" and "b":
|
|
*
|
|
* <programlisting>
|
|
* CPU 0 CPU 1
|
|
*
|
|
* a = 2;
|
|
* memory_barrier();
|
|
* b = 3; y = b;
|
|
* read_barrier_depends();
|
|
* x = a;
|
|
* </programlisting>
|
|
*
|
|
* does not enforce ordering, since there is no data dependency between
|
|
* the read of "a" and the read of "b". Therefore, on some CPUs, such
|
|
* as Alpha, "y" could be set to 3 and "x" to 0. Use rmb()
|
|
* in cases like thiswhere there are no data dependencies.
|
|
**/
|
|
|
|
#define read_barrier_depends() do { } while(0)
|
|
|
|
#ifdef CONFIG_X86_OOSTORE
|
|
/* Actually there are no OOO store capable CPUs for now that do SSE,
|
|
but make it already an possibility. */
|
|
#define wmb() alternative("lock; addl $0,0(%%esp)", "sfence", X86_FEATURE_XMM)
|
|
#else
|
|
#define wmb() __asm__ __volatile__ ("": : :"memory")
|
|
#endif
|
|
|
|
#ifdef CONFIG_SMP
|
|
#define smp_mb() mb()
|
|
#define smp_rmb() rmb()
|
|
#define smp_wmb() wmb()
|
|
#define smp_read_barrier_depends() read_barrier_depends()
|
|
#define set_mb(var, value) do { (void) xchg(&var, value); } while (0)
|
|
#else
|
|
#define smp_mb() barrier()
|
|
#define smp_rmb() barrier()
|
|
#define smp_wmb() barrier()
|
|
#define smp_read_barrier_depends() do { } while(0)
|
|
#define set_mb(var, value) do { var = value; barrier(); } while (0)
|
|
#endif
|
|
|
|
#define set_wmb(var, value) do { var = value; wmb(); } while (0)
|
|
|
|
/* interrupt control.. */
|
|
#define local_save_flags(x) do { typecheck(unsigned long,x); __asm__ __volatile__("pushfl ; popl %0":"=g" (x): /* no input */); } while (0)
|
|
#define local_irq_restore(x) do { typecheck(unsigned long,x); __asm__ __volatile__("pushl %0 ; popfl": /* no output */ :"g" (x):"memory", "cc"); } while (0)
|
|
#define local_irq_disable() __asm__ __volatile__("cli": : :"memory")
|
|
#define local_irq_enable() __asm__ __volatile__("sti": : :"memory")
|
|
/* used in the idle loop; sti takes one instruction cycle to complete */
|
|
#define safe_halt() __asm__ __volatile__("sti; hlt": : :"memory")
|
|
/* used when interrupts are already enabled or to shutdown the processor */
|
|
#define halt() __asm__ __volatile__("hlt": : :"memory")
|
|
|
|
#define irqs_disabled() \
|
|
({ \
|
|
unsigned long flags; \
|
|
local_save_flags(flags); \
|
|
!(flags & (1<<9)); \
|
|
})
|
|
|
|
/* For spinlocks etc */
|
|
#define local_irq_save(x) __asm__ __volatile__("pushfl ; popl %0 ; cli":"=g" (x): /* no input */ :"memory")
|
|
|
|
/*
|
|
* disable hlt during certain critical i/o operations
|
|
*/
|
|
#define HAVE_DISABLE_HLT
|
|
void disable_hlt(void);
|
|
void enable_hlt(void);
|
|
|
|
extern int es7000_plat;
|
|
void cpu_idle_wait(void);
|
|
|
|
/*
|
|
* On SMP systems, when the scheduler does migration-cost autodetection,
|
|
* it needs a way to flush as much of the CPU's caches as possible:
|
|
*/
|
|
static inline void sched_cacheflush(void)
|
|
{
|
|
wbinvd();
|
|
}
|
|
|
|
extern unsigned long arch_align_stack(unsigned long sp);
|
|
|
|
#endif
|