include/asm-i386/msr.h

   1 #ifndef __ASM_MSR_H
   2 #define __ASM_MSR_H
   3
   4 #include <asm/msr-index.h>
   5
   6 #ifdef __KERNEL__
   7 #ifndef __ASSEMBLY__
   8
   9 #include <asm/errno.h>
  10
  11 static inline unsigned long long native_read_msr(unsigned int msr)
  12 {
  13         unsigned long long val;
  14
  15         asm volatile("rdmsr" : "=A" (val) : "c" (msr));
  16         return val;
  17 }
  18
  19 static inline unsigned long long native_read_msr_safe(unsigned int msr,
  20                                                       int *err)
  21 {
  22         unsigned long long val;
  23
  24         asm volatile("2: rdmsr ; xorl %0,%0\n"
  25                      "1:\n\t"
  26                      ".section .fixup,\"ax\"\n\t"
  27                      "3:  movl %3,%0 ; jmp 1b\n\t"
  28                      ".previous\n\t"
  29                      ".section __ex_table,\"a\"\n"
  30                      "   .align 4\n\t"
  31                      "   .long  2b,3b\n\t"
  32                      ".previous"
  33                      : "=r" (*err), "=A" (val)
  34                      : "c" (msr), "i" (-EFAULT));
  35
  36         return val;
  37 }
  38
  39 static inline void native_write_msr(unsigned int msr, unsigned long long val)
  40 {
  41         asm volatile("wrmsr" : : "c" (msr), "A"(val));
  42 }
  43
  44 static inline int native_write_msr_safe(unsigned int msr,
  45                                         unsigned long long val)
  46 {
  47         int err;
  48         asm volatile("2: wrmsr ; xorl %0,%0\n"
  49                      "1:\n\t"
  50                      ".section .fixup,\"ax\"\n\t"
  51                      "3:  movl %4,%0 ; jmp 1b\n\t"
  52                      ".previous\n\t"
  53                      ".section __ex_table,\"a\"\n"
  54                      "   .align 4\n\t"
  55                      "   .long  2b,3b\n\t"
  56                      ".previous"
  57                      : "=a" (err)
  58                      : "c" (msr), "0" ((u32)val), "d" ((u32)(val>>32)),
  59                        "i" (-EFAULT));
  60         return err;
  61 }
  62
  63 static inline unsigned long long native_read_tsc(void)
  64 {
  65         unsigned long long val;
  66         asm volatile("rdtsc" : "=A" (val));
  67         return val;
  68 }
  69
  70 static inline unsigned long long native_read_pmc(void)
  71 {
  72         unsigned long long val;
  73         asm volatile("rdpmc" : "=A" (val));
  74         return val;
  75 }
  76
  77 #ifdef CONFIG_PARAVIRT
  78 #include <asm/paravirt.h>
  79 #else
  80 #include <linux/errno.h>
  81 /*
  82  * Access to machine-specific registers (available on 586 and better only)
  83  * Note: the rd* operations modify the parameters directly (without using
  84  * pointer indirection), this allows gcc to optimize better
  85  */
  86
  87 #define rdmsr(msr,val1,val2)                                            \
  88         do {                                                            \
  89                 u64 __val = native_read_msr(msr);                       \
  90                 (val1) = (u32)__val;                                    \
  91                 (val2) = (u32)(__val >> 32);                            \
  92         } while(0)
  93
  94 static inline void wrmsr(u32 __msr, u32 __low, u32 __high)
  95 {
  96         native_write_msr(__msr, ((u64)__high << 32) | __low);
  97 }
  98
  99 #define rdmsrl(msr,val)                                                 \
 100         ((val) = native_read_msr(msr))
 101
 102 #define wrmsrl(msr,val) native_write_msr(msr, val)
 103
 104 /* wrmsr with exception handling */
 105 static inline int wrmsr_safe(u32 __msr, u32 __low, u32 __high)
 106 {
 107         return native_write_msr_safe(__msr, ((u64)__high << 32) | __low);
 108 }
 109
 110 /* rdmsr with exception handling */
 111 #define rdmsr_safe(msr,p1,p2)                                           \
 112         ({                                                              \
 113                 int __err;                                              \
 114                 u64 __val = native_read_msr_safe(msr, &__err);          \
 115                 (*p1) = (u32)__val;                                     \
 116                 (*p2) = (u32)(__val >> 32);                             \
 117                 __err;                                                  \
 118         })
 119
 120 #define rdtscl(low)                                             \
 121         ((low) = (u32)native_read_tsc())
 122
 123 #define rdtscll(val)                                            \
 124         ((val) = native_read_tsc())
 125
 126 #define write_tsc(val1,val2) wrmsr(0x10, val1, val2)
 127
 128 #define rdpmc(counter,low,high)                                 \
 129         do {                                                    \
 130                 u64 _l = native_read_pmc();                     \
 131                 (low)  = (u32)_l;                               \
 132                 (high) = (u32)(_l >> 32);                       \
 133         } while(0)
 134 #endif  /* !CONFIG_PARAVIRT */
 135
 136 #ifdef CONFIG_SMP
 137 void rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h);
 138 void wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h);
 139 int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h);
 140 int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h);
 141 #else  /*  CONFIG_SMP  */
 142 static inline void rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h)
 143 {
 144         rdmsr(msr_no, *l, *h);
 145 }
 146 static inline void wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
 147 {
 148         wrmsr(msr_no, l, h);
 149 }
 150 static inline int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h)
 151 {
 152         return rdmsr_safe(msr_no, l, h);
 153 }
 154 static inline int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
 155 {
 156         return wrmsr_safe(msr_no, l, h);
 157 }
 158 #endif  /*  CONFIG_SMP  */
 159 #endif
 160 #endif
 161 #endif /* __ASM_MSR_H */