mirror of
https://github.com/torvalds/linux.git
synced 2024-12-29 14:21:47 +00:00
344 lines
9.7 KiB
C
344 lines
9.7 KiB
C
|
#ifndef __ASM_SYSTEM_H
|
||
|
#define __ASM_SYSTEM_H
|
||
|
|
||
|
#include <linux/config.h>
|
||
|
#include <linux/kernel.h>
|
||
|
#include <asm/segment.h>
|
||
|
|
||
|
#ifdef __KERNEL__
|
||
|
|
||
|
#ifdef CONFIG_SMP
|
||
|
#define LOCK_PREFIX "lock ; "
|
||
|
#else
|
||
|
#define LOCK_PREFIX ""
|
||
|
#endif
|
||
|
|
||
|
#define __STR(x) #x
|
||
|
#define STR(x) __STR(x)
|
||
|
|
||
|
#define __SAVE(reg,offset) "movq %%" #reg ",(14-" #offset ")*8(%%rsp)\n\t"
|
||
|
#define __RESTORE(reg,offset) "movq (14-" #offset ")*8(%%rsp),%%" #reg "\n\t"
|
||
|
|
||
|
/* frame pointer must be last for get_wchan */
|
||
|
#define SAVE_CONTEXT "pushfq ; pushq %%rbp ; movq %%rsi,%%rbp\n\t"
|
||
|
#define RESTORE_CONTEXT "movq %%rbp,%%rsi ; popq %%rbp ; popfq\n\t"
|
||
|
|
||
|
#define __EXTRA_CLOBBER \
|
||
|
,"rcx","rbx","rdx","r8","r9","r10","r11","r12","r13","r14","r15"
|
||
|
|
||
|
#define switch_to(prev,next,last) \
|
||
|
asm volatile(SAVE_CONTEXT \
|
||
|
"movq %%rsp,%P[threadrsp](%[prev])\n\t" /* save RSP */ \
|
||
|
"movq %P[threadrsp](%[next]),%%rsp\n\t" /* restore RSP */ \
|
||
|
"call __switch_to\n\t" \
|
||
|
".globl thread_return\n" \
|
||
|
"thread_return:\n\t" \
|
||
|
"movq %%gs:%P[pda_pcurrent],%%rsi\n\t" \
|
||
|
"movq %P[thread_info](%%rsi),%%r8\n\t" \
|
||
|
LOCK "btr %[tif_fork],%P[ti_flags](%%r8)\n\t" \
|
||
|
"movq %%rax,%%rdi\n\t" \
|
||
|
"jc ret_from_fork\n\t" \
|
||
|
RESTORE_CONTEXT \
|
||
|
: "=a" (last) \
|
||
|
: [next] "S" (next), [prev] "D" (prev), \
|
||
|
[threadrsp] "i" (offsetof(struct task_struct, thread.rsp)), \
|
||
|
[ti_flags] "i" (offsetof(struct thread_info, flags)),\
|
||
|
[tif_fork] "i" (TIF_FORK), \
|
||
|
[thread_info] "i" (offsetof(struct task_struct, thread_info)), \
|
||
|
[pda_pcurrent] "i" (offsetof(struct x8664_pda, pcurrent)) \
|
||
|
: "memory", "cc" __EXTRA_CLOBBER)
|
||
|
|
||
|
extern void load_gs_index(unsigned);
|
||
|
|
||
|
/*
|
||
|
* Load a segment. Fall back on loading the zero
|
||
|
* segment if something goes wrong..
|
||
|
*/
|
||
|
#define loadsegment(seg,value) \
|
||
|
asm volatile("\n" \
|
||
|
"1:\t" \
|
||
|
"movl %k0,%%" #seg "\n" \
|
||
|
"2:\n" \
|
||
|
".section .fixup,\"ax\"\n" \
|
||
|
"3:\t" \
|
||
|
"movl %1,%%" #seg "\n\t" \
|
||
|
"jmp 2b\n" \
|
||
|
".previous\n" \
|
||
|
".section __ex_table,\"a\"\n\t" \
|
||
|
".align 8\n\t" \
|
||
|
".quad 1b,3b\n" \
|
||
|
".previous" \
|
||
|
: :"r" (value), "r" (0))
|
||
|
|
||
|
#define set_debug(value,register) \
|
||
|
__asm__("movq %0,%%db" #register \
|
||
|
: /* no output */ \
|
||
|
:"r" ((unsigned long) value))
|
||
|
|
||
|
|
||
|
#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[5];
|
||
|
};
|
||
|
#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 8\n" \
|
||
|
" .quad 661b\n" /* label */ \
|
||
|
" .quad 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 8\n" \
|
||
|
" .quad 661b\n" /* label */ \
|
||
|
" .quad 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)
|
||
|
|
||
|
/*
|
||
|
* Clear and set 'TS' bit respectively
|
||
|
*/
|
||
|
#define clts() __asm__ __volatile__ ("clts")
|
||
|
|
||
|
static inline unsigned long read_cr0(void)
|
||
|
{
|
||
|
unsigned long cr0;
|
||
|
asm volatile("movq %%cr0,%0" : "=r" (cr0));
|
||
|
return cr0;
|
||
|
}
|
||
|
|
||
|
static inline void write_cr0(unsigned long val)
|
||
|
{
|
||
|
asm volatile("movq %0,%%cr0" :: "r" (val));
|
||
|
}
|
||
|
|
||
|
static inline unsigned long read_cr3(void)
|
||
|
{
|
||
|
unsigned long cr3;
|
||
|
asm("movq %%cr3,%0" : "=r" (cr3));
|
||
|
return cr3;
|
||
|
}
|
||
|
|
||
|
static inline unsigned long read_cr4(void)
|
||
|
{
|
||
|
unsigned long cr4;
|
||
|
asm("movq %%cr4,%0" : "=r" (cr4));
|
||
|
return cr4;
|
||
|
}
|
||
|
|
||
|
static inline void write_cr4(unsigned long val)
|
||
|
{
|
||
|
asm volatile("movq %0,%%cr4" :: "r" (val));
|
||
|
}
|
||
|
|
||
|
#define stts() write_cr0(8 | read_cr0())
|
||
|
|
||
|
#define wbinvd() \
|
||
|
__asm__ __volatile__ ("wbinvd": : :"memory");
|
||
|
|
||
|
#endif /* __KERNEL__ */
|
||
|
|
||
|
#define nop() __asm__ __volatile__ ("nop")
|
||
|
|
||
|
#define xchg(ptr,v) ((__typeof__(*(ptr)))__xchg((unsigned long)(v),(ptr),sizeof(*(ptr))))
|
||
|
|
||
|
#define tas(ptr) (xchg((ptr),1))
|
||
|
|
||
|
#define __xg(x) ((volatile long *)(x))
|
||
|
|
||
|
extern inline void set_64bit(volatile unsigned long *ptr, unsigned long val)
|
||
|
{
|
||
|
*ptr = val;
|
||
|
}
|
||
|
|
||
|
#define _set_64bit set_64bit
|
||
|
|
||
|
/*
|
||
|
* 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 %k0,%1"
|
||
|
:"=r" (x)
|
||
|
:"m" (*__xg(ptr)), "0" (x)
|
||
|
:"memory");
|
||
|
break;
|
||
|
case 8:
|
||
|
__asm__ __volatile__("xchgq %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.
|
||
|
*/
|
||
|
|
||
|
#define __HAVE_ARCH_CMPXCHG 1
|
||
|
|
||
|
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)
|
||
|
: "q"(new), "m"(*__xg(ptr)), "0"(old)
|
||
|
: "memory");
|
||
|
return prev;
|
||
|
case 4:
|
||
|
__asm__ __volatile__(LOCK_PREFIX "cmpxchgl %k1,%2"
|
||
|
: "=a"(prev)
|
||
|
: "q"(new), "m"(*__xg(ptr)), "0"(old)
|
||
|
: "memory");
|
||
|
return prev;
|
||
|
case 8:
|
||
|
__asm__ __volatile__(LOCK_PREFIX "cmpxchgq %1,%2"
|
||
|
: "=a"(prev)
|
||
|
: "q"(new), "m"(*__xg(ptr)), "0"(old)
|
||
|
: "memory");
|
||
|
return prev;
|
||
|
}
|
||
|
return old;
|
||
|
}
|
||
|
|
||
|
#define cmpxchg(ptr,o,n)\
|
||
|
((__typeof__(*(ptr)))__cmpxchg((ptr),(unsigned long)(o),\
|
||
|
(unsigned long)(n),sizeof(*(ptr))))
|
||
|
|
||
|
#ifdef CONFIG_SMP
|
||
|
#define smp_mb() mb()
|
||
|
#define smp_rmb() rmb()
|
||
|
#define smp_wmb() wmb()
|
||
|
#define smp_read_barrier_depends() do {} while(0)
|
||
|
#else
|
||
|
#define smp_mb() barrier()
|
||
|
#define smp_rmb() barrier()
|
||
|
#define smp_wmb() barrier()
|
||
|
#define smp_read_barrier_depends() do {} while(0)
|
||
|
#endif
|
||
|
|
||
|
|
||
|
/*
|
||
|
* Force strict CPU ordering.
|
||
|
* And yes, this is required on UP too when we're talking
|
||
|
* to devices.
|
||
|
*/
|
||
|
#define mb() asm volatile("mfence":::"memory")
|
||
|
#define rmb() asm volatile("lfence":::"memory")
|
||
|
|
||
|
#ifdef CONFIG_UNORDERED_IO
|
||
|
#define wmb() asm volatile("sfence" ::: "memory")
|
||
|
#else
|
||
|
#define wmb() asm volatile("" ::: "memory")
|
||
|
#endif
|
||
|
#define read_barrier_depends() do {} while(0)
|
||
|
#define set_mb(var, value) do { xchg(&var, value); } while (0)
|
||
|
#define set_wmb(var, value) do { var = value; wmb(); } while (0)
|
||
|
|
||
|
#define warn_if_not_ulong(x) do { unsigned long foo; (void) (&(x) == &foo); } while (0)
|
||
|
|
||
|
/* interrupt control.. */
|
||
|
#define local_save_flags(x) do { warn_if_not_ulong(x); __asm__ __volatile__("# save_flags \n\t pushfq ; popq %q0":"=g" (x): /* no input */ :"memory"); } while (0)
|
||
|
#define local_irq_restore(x) __asm__ __volatile__("# restore_flags \n\t pushq %0 ; popfq": /* no output */ :"g" (x):"memory", "cc")
|
||
|
#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")
|
||
|
|
||
|
#define irqs_disabled() \
|
||
|
({ \
|
||
|
unsigned long flags; \
|
||
|
local_save_flags(flags); \
|
||
|
!(flags & (1<<9)); \
|
||
|
})
|
||
|
|
||
|
/* For spinlocks etc */
|
||
|
#define local_irq_save(x) do { warn_if_not_ulong(x); __asm__ __volatile__("# local_irq_save \n\t pushfq ; popq %0 ; cli":"=g" (x): /* no input */ :"memory"); } while (0)
|
||
|
|
||
|
void cpu_idle_wait(void);
|
||
|
|
||
|
/*
|
||
|
* disable hlt during certain critical i/o operations
|
||
|
*/
|
||
|
#define HAVE_DISABLE_HLT
|
||
|
void disable_hlt(void);
|
||
|
void enable_hlt(void);
|
||
|
|
||
|
#define HAVE_EAT_KEY
|
||
|
void eat_key(void);
|
||
|
|
||
|
extern unsigned long arch_align_stack(unsigned long sp);
|
||
|
|
||
|
#endif
|