arch/x86/include/asm/msr.h

   1 #ifndef _ASM_X86_MSR_H
   2 #define _ASM_X86_MSR_H
   3
   4 #include <asm/msr-index.h>
   5
   6 #ifdef __KERNEL__
   7 #ifndef __ASSEMBLY__
   8
   9 #include <linux/types.h>
  10 #include <asm/asm.h>
  11 #include <asm/errno.h>
  12 #include <asm/cpumask.h>
  13
  14 struct msr {
  15         union {
  16                 struct {
  17                         u32 l;
  18                         u32 h;
  19                 };
  20                 u64 q;
  21         };
  22 };
  23
  24 static inline unsigned long long native_read_tscp(unsigned int *aux)
  25 {
  26         unsigned long low, high;
  27         asm volatile(".byte 0x0f,0x01,0xf9"
  28                      : "=a" (low), "=d" (high), "=c" (*aux));
  29         return low | ((u64)high << 32);
  30 }
  31
  32 /*
  33  * both i386 and x86_64 returns 64-bit value in edx:eax, but gcc's "A"
  34  * constraint has different meanings. For i386, "A" means exactly
  35  * edx:eax, while for x86_64 it doesn't mean rdx:rax or edx:eax. Instead,
  36  * it means rax *or* rdx.
  37  */
  38 #ifdef CONFIG_X86_64
  39 #define DECLARE_ARGS(val, low, high)    unsigned low, high
  40 #define EAX_EDX_VAL(val, low, high)     ((low) | ((u64)(high) << 32))
  41 #define EAX_EDX_ARGS(val, low, high)    "a" (low), "d" (high)
  42 #define EAX_EDX_RET(val, low, high)     "=a" (low), "=d" (high)
  43 #else
  44 #define DECLARE_ARGS(val, low, high)    unsigned long long val
  45 #define EAX_EDX_VAL(val, low, high)     (val)
  46 #define EAX_EDX_ARGS(val, low, high)    "A" (val)
  47 #define EAX_EDX_RET(val, low, high)     "=A" (val)
  48 #endif
  49
  50 static inline unsigned long long native_read_msr(unsigned int msr)
  51 {
  52         DECLARE_ARGS(val, low, high);
  53
  54         asm volatile("rdmsr" : EAX_EDX_RET(val, low, high) : "c" (msr));
  55         return EAX_EDX_VAL(val, low, high);
  56 }
  57
  58 static inline unsigned long long native_read_msr_safe(unsigned int msr,
  59                                                       int *err)
  60 {
  61         DECLARE_ARGS(val, low, high);
  62
  63         asm volatile("2: rdmsr ; xor %[err],%[err]\n"
  64                      "1:\n\t"
  65                      ".section .fixup,\"ax\"\n\t"
  66                      "3:  mov %[fault],%[err] ; jmp 1b\n\t"
  67                      ".previous\n\t"
  68                      _ASM_EXTABLE(2b, 3b)
  69                      : [err] "=r" (*err), EAX_EDX_RET(val, low, high)
  70                      : "c" (msr), [fault] "i" (-EFAULT));
  71         return EAX_EDX_VAL(val, low, high);
  72 }
  73
  74 static inline unsigned long long native_read_msr_amd_safe(unsigned int msr,
  75                                                       int *err)
  76 {
  77         DECLARE_ARGS(val, low, high);
  78
  79         asm volatile("2: rdmsr ; xor %0,%0\n"
  80                      "1:\n\t"
  81                      ".section .fixup,\"ax\"\n\t"
  82                      "3:  mov %3,%0 ; jmp 1b\n\t"
  83                      ".previous\n\t"
  84                      _ASM_EXTABLE(2b, 3b)
  85                      : "=r" (*err), EAX_EDX_RET(val, low, high)
  86                      : "c" (msr), "D" (0x9c5a203a), "i" (-EFAULT));
  87         return EAX_EDX_VAL(val, low, high);
  88 }
  89
  90 static inline void native_write_msr(unsigned int msr,
  91                                     unsigned low, unsigned high)
  92 {
  93         asm volatile("wrmsr" : : "c" (msr), "a"(low), "d" (high) : "memory");
  94 }
  95
  96 /* Can be uninlined because referenced by paravirt */
  97 notrace static inline int native_write_msr_safe(unsigned int msr,
  98                                         unsigned low, unsigned high)
  99 {
 100         int err;
 101         asm volatile("2: wrmsr ; xor %[err],%[err]\n"
 102                      "1:\n\t"
 103                      ".section .fixup,\"ax\"\n\t"
 104                      "3:  mov %[fault],%[err] ; jmp 1b\n\t"
 105                      ".previous\n\t"
 106                      _ASM_EXTABLE(2b, 3b)
 107                      : [err] "=a" (err)
 108                      : "c" (msr), "0" (low), "d" (high),
 109                        [fault] "i" (-EFAULT)
 110                      : "memory");
 111         return err;
 112 }
 113
 114 extern unsigned long long native_read_tsc(void);
 115
 116 static __always_inline unsigned long long __native_read_tsc(void)
 117 {
 118         DECLARE_ARGS(val, low, high);
 119
 120         asm volatile("rdtsc" : EAX_EDX_RET(val, low, high));
 121
 122         return EAX_EDX_VAL(val, low, high);
 123 }
 124
 125 static inline unsigned long long native_read_pmc(int counter)
 126 {
 127         DECLARE_ARGS(val, low, high);
 128
 129         asm volatile("rdpmc" : EAX_EDX_RET(val, low, high) : "c" (counter));
 130         return EAX_EDX_VAL(val, low, high);
 131 }
 132
 133 #ifdef CONFIG_PARAVIRT
 134 #include <asm/paravirt.h>
 135 #else
 136 #include <linux/errno.h>
 137 /*
 138  * Access to machine-specific registers (available on 586 and better only)
 139  * Note: the rd* operations modify the parameters directly (without using
 140  * pointer indirection), this allows gcc to optimize better
 141  */
 142
 143 #define rdmsr(msr, val1, val2)                                  \
 144 do {                                                            \
 145         u64 __val = native_read_msr((msr));                     \
 146         (val1) = (u32)__val;                                    \
 147         (val2) = (u32)(__val >> 32);                            \
 148 } while (0)
 149
 150 static inline void wrmsr(unsigned msr, unsigned low, unsigned high)
 151 {
 152         native_write_msr(msr, low, high);
 153 }
 154
 155 #define rdmsrl(msr, val)                        \
 156         ((val) = native_read_msr((msr)))
 157
 158 #define wrmsrl(msr, val)                                                \
 159         native_write_msr((msr), (u32)((u64)(val)), (u32)((u64)(val) >> 32))
 160
 161 /* wrmsr with exception handling */
 162 static inline int wrmsr_safe(unsigned msr, unsigned low, unsigned high)
 163 {
 164         return native_write_msr_safe(msr, low, high);
 165 }
 166
 167 /* rdmsr with exception handling */
 168 #define rdmsr_safe(msr, p1, p2)                                 \
 169 ({                                                              \
 170         int __err;                                              \
 171         u64 __val = native_read_msr_safe((msr), &__err);        \
 172         (*p1) = (u32)__val;                                     \
 173         (*p2) = (u32)(__val >> 32);                             \
 174         __err;                                                  \
 175 })
 176
 177 static inline int rdmsrl_safe(unsigned msr, unsigned long long *p)
 178 {
 179         int err;
 180
 181         *p = native_read_msr_safe(msr, &err);
 182         return err;
 183 }
 184 static inline int rdmsrl_amd_safe(unsigned msr, unsigned long long *p)
 185 {
 186         int err;
 187
 188         *p = native_read_msr_amd_safe(msr, &err);
 189         return err;
 190 }
 191
 192 #define rdtscl(low)                                             \
 193         ((low) = (u32)__native_read_tsc())
 194
 195 #define rdtscll(val)                                            \
 196         ((val) = __native_read_tsc())
 197
 198 #define rdpmc(counter, low, high)                       \
 199 do {                                                    \
 200         u64 _l = native_read_pmc((counter));            \
 201         (low)  = (u32)_l;                               \
 202         (high) = (u32)(_l >> 32);                       \
 203 } while (0)
 204
 205 #define rdtscp(low, high, aux)                                  \
 206 do {                                                            \
 207         unsigned long long _val = native_read_tscp(&(aux));     \
 208         (low) = (u32)_val;                                      \
 209         (high) = (u32)(_val >> 32);                             \
 210 } while (0)
 211
 212 #define rdtscpll(val, aux) (val) = native_read_tscp(&(aux))
 213
 214 #endif  /* !CONFIG_PARAVIRT */
 215
 216
 217 #define checking_wrmsrl(msr, val) wrmsr_safe((msr), (u32)(val),         \
 218                                              (u32)((val) >> 32))
 219
 220 #define write_tsc(val1, val2) wrmsr(0x10, (val1), (val2))
 221
 222 #define write_rdtscp_aux(val) wrmsr(0xc0000103, (val), 0)
 223
 224 #ifdef CONFIG_SMP
 225 int rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h);
 226 int wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h);
 227 void rdmsr_on_cpus(const cpumask_t *mask, u32 msr_no, struct msr *msrs);
 228 void wrmsr_on_cpus(const cpumask_t *mask, u32 msr_no, struct msr *msrs);
 229 int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h);
 230 int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h);
 231 #else  /*  CONFIG_SMP  */
 232 static inline int rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h)
 233 {
 234         rdmsr(msr_no, *l, *h);
 235         return 0;
 236 }
 237 static inline int wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
 238 {
 239         wrmsr(msr_no, l, h);
 240         return 0;
 241 }
 242 static inline void rdmsr_on_cpus(const cpumask_t *m, u32 msr_no,
 243                                 struct msr *msrs)
 244 {
 245        rdmsr_on_cpu(0, msr_no, &(msrs[0].l), &(msrs[0].h));
 246 }
 247 static inline void wrmsr_on_cpus(const cpumask_t *m, u32 msr_no,
 248                                 struct msr *msrs)
 249 {
 250        wrmsr_on_cpu(0, msr_no, msrs[0].l, msrs[0].h);
 251 }
 252 static inline int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no,
 253                                     u32 *l, u32 *h)
 254 {
 255         return rdmsr_safe(msr_no, l, h);
 256 }
 257 static inline int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
 258 {
 259         return wrmsr_safe(msr_no, l, h);
 260 }
 261 #endif  /* CONFIG_SMP */
 262 #endif /* __ASSEMBLY__ */
 263 #endif /* __KERNEL__ */
 264 #endif /* _ASM_X86_MSR_H */