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Diffstat (limited to 'include/asm-x86_64/system.h')
-rw-r--r-- | include/asm-x86_64/system.h | 343 |
1 files changed, 343 insertions, 0 deletions
diff --git a/include/asm-x86_64/system.h b/include/asm-x86_64/system.h new file mode 100644 index 000000000000..76165736e43a --- /dev/null +++ b/include/asm-x86_64/system.h @@ -0,0 +1,343 @@ +#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 |