xref: /linux/arch/x86/include/asm/msr.h (revision 93df8a1ed6231727c5db94a80b1a6bd5ee67cec3)
1 #ifndef _ASM_X86_MSR_H
2 #define _ASM_X86_MSR_H
3 
4 #include "msr-index.h"
5 
6 #ifndef __ASSEMBLY__
7 
8 #include <asm/asm.h>
9 #include <asm/errno.h>
10 #include <asm/cpumask.h>
11 #include <uapi/asm/msr.h>
12 
13 struct msr {
14 	union {
15 		struct {
16 			u32 l;
17 			u32 h;
18 		};
19 		u64 q;
20 	};
21 };
22 
23 struct msr_info {
24 	u32 msr_no;
25 	struct msr reg;
26 	struct msr *msrs;
27 	int err;
28 };
29 
30 struct msr_regs_info {
31 	u32 *regs;
32 	int err;
33 };
34 
35 static inline unsigned long long native_read_tscp(unsigned int *aux)
36 {
37 	unsigned long low, high;
38 	asm volatile(".byte 0x0f,0x01,0xf9"
39 		     : "=a" (low), "=d" (high), "=c" (*aux));
40 	return low | ((u64)high << 32);
41 }
42 
43 /*
44  * both i386 and x86_64 returns 64-bit value in edx:eax, but gcc's "A"
45  * constraint has different meanings. For i386, "A" means exactly
46  * edx:eax, while for x86_64 it doesn't mean rdx:rax or edx:eax. Instead,
47  * it means rax *or* rdx.
48  */
49 #ifdef CONFIG_X86_64
50 #define DECLARE_ARGS(val, low, high)	unsigned low, high
51 #define EAX_EDX_VAL(val, low, high)	((low) | ((u64)(high) << 32))
52 #define EAX_EDX_ARGS(val, low, high)	"a" (low), "d" (high)
53 #define EAX_EDX_RET(val, low, high)	"=a" (low), "=d" (high)
54 #else
55 #define DECLARE_ARGS(val, low, high)	unsigned long long val
56 #define EAX_EDX_VAL(val, low, high)	(val)
57 #define EAX_EDX_ARGS(val, low, high)	"A" (val)
58 #define EAX_EDX_RET(val, low, high)	"=A" (val)
59 #endif
60 
61 static inline unsigned long long native_read_msr(unsigned int msr)
62 {
63 	DECLARE_ARGS(val, low, high);
64 
65 	asm volatile("rdmsr" : EAX_EDX_RET(val, low, high) : "c" (msr));
66 	return EAX_EDX_VAL(val, low, high);
67 }
68 
69 static inline unsigned long long native_read_msr_safe(unsigned int msr,
70 						      int *err)
71 {
72 	DECLARE_ARGS(val, low, high);
73 
74 	asm volatile("2: rdmsr ; xor %[err],%[err]\n"
75 		     "1:\n\t"
76 		     ".section .fixup,\"ax\"\n\t"
77 		     "3:  mov %[fault],%[err] ; jmp 1b\n\t"
78 		     ".previous\n\t"
79 		     _ASM_EXTABLE(2b, 3b)
80 		     : [err] "=r" (*err), EAX_EDX_RET(val, low, high)
81 		     : "c" (msr), [fault] "i" (-EIO));
82 	return EAX_EDX_VAL(val, low, high);
83 }
84 
85 static inline void native_write_msr(unsigned int msr,
86 				    unsigned low, unsigned high)
87 {
88 	asm volatile("wrmsr" : : "c" (msr), "a"(low), "d" (high) : "memory");
89 }
90 
91 /* Can be uninlined because referenced by paravirt */
92 notrace static inline int native_write_msr_safe(unsigned int msr,
93 					unsigned low, unsigned high)
94 {
95 	int err;
96 	asm volatile("2: wrmsr ; xor %[err],%[err]\n"
97 		     "1:\n\t"
98 		     ".section .fixup,\"ax\"\n\t"
99 		     "3:  mov %[fault],%[err] ; jmp 1b\n\t"
100 		     ".previous\n\t"
101 		     _ASM_EXTABLE(2b, 3b)
102 		     : [err] "=a" (err)
103 		     : "c" (msr), "0" (low), "d" (high),
104 		       [fault] "i" (-EIO)
105 		     : "memory");
106 	return err;
107 }
108 
109 extern unsigned long long native_read_tsc(void);
110 
111 extern int rdmsr_safe_regs(u32 regs[8]);
112 extern int wrmsr_safe_regs(u32 regs[8]);
113 
114 static __always_inline unsigned long long __native_read_tsc(void)
115 {
116 	DECLARE_ARGS(val, low, high);
117 
118 	asm volatile("rdtsc" : EAX_EDX_RET(val, low, high));
119 
120 	return EAX_EDX_VAL(val, low, high);
121 }
122 
123 static inline unsigned long long native_read_pmc(int counter)
124 {
125 	DECLARE_ARGS(val, low, high);
126 
127 	asm volatile("rdpmc" : EAX_EDX_RET(val, low, high) : "c" (counter));
128 	return EAX_EDX_VAL(val, low, high);
129 }
130 
131 #ifdef CONFIG_PARAVIRT
132 #include <asm/paravirt.h>
133 #else
134 #include <linux/errno.h>
135 /*
136  * Access to machine-specific registers (available on 586 and better only)
137  * Note: the rd* operations modify the parameters directly (without using
138  * pointer indirection), this allows gcc to optimize better
139  */
140 
141 #define rdmsr(msr, low, high)					\
142 do {								\
143 	u64 __val = native_read_msr((msr));			\
144 	(void)((low) = (u32)__val);				\
145 	(void)((high) = (u32)(__val >> 32));			\
146 } while (0)
147 
148 static inline void wrmsr(unsigned msr, unsigned low, unsigned high)
149 {
150 	native_write_msr(msr, low, high);
151 }
152 
153 #define rdmsrl(msr, val)			\
154 	((val) = native_read_msr((msr)))
155 
156 #define wrmsrl(msr, val)						\
157 	native_write_msr((msr), (u32)((u64)(val)), (u32)((u64)(val) >> 32))
158 
159 /* wrmsr with exception handling */
160 static inline int wrmsr_safe(unsigned msr, unsigned low, unsigned high)
161 {
162 	return native_write_msr_safe(msr, low, high);
163 }
164 
165 /* rdmsr with exception handling */
166 #define rdmsr_safe(msr, low, high)				\
167 ({								\
168 	int __err;						\
169 	u64 __val = native_read_msr_safe((msr), &__err);	\
170 	(*low) = (u32)__val;					\
171 	(*high) = (u32)(__val >> 32);				\
172 	__err;							\
173 })
174 
175 static inline int rdmsrl_safe(unsigned msr, unsigned long long *p)
176 {
177 	int err;
178 
179 	*p = native_read_msr_safe(msr, &err);
180 	return err;
181 }
182 
183 #define rdtscl(low)						\
184 	((low) = (u32)__native_read_tsc())
185 
186 #define rdtscll(val)						\
187 	((val) = __native_read_tsc())
188 
189 #define rdpmc(counter, low, high)			\
190 do {							\
191 	u64 _l = native_read_pmc((counter));		\
192 	(low)  = (u32)_l;				\
193 	(high) = (u32)(_l >> 32);			\
194 } while (0)
195 
196 #define rdpmcl(counter, val) ((val) = native_read_pmc(counter))
197 
198 #define rdtscp(low, high, aux)					\
199 do {                                                            \
200 	unsigned long long _val = native_read_tscp(&(aux));     \
201 	(low) = (u32)_val;                                      \
202 	(high) = (u32)(_val >> 32);                             \
203 } while (0)
204 
205 #define rdtscpll(val, aux) (val) = native_read_tscp(&(aux))
206 
207 #endif	/* !CONFIG_PARAVIRT */
208 
209 /*
210  * 64-bit version of wrmsr_safe():
211  */
212 static inline int wrmsrl_safe(u32 msr, u64 val)
213 {
214 	return wrmsr_safe(msr, (u32)val,  (u32)(val >> 32));
215 }
216 
217 #define write_tsc(low, high) wrmsr(MSR_IA32_TSC, (low), (high))
218 
219 #define write_rdtscp_aux(val) wrmsr(MSR_TSC_AUX, (val), 0)
220 
221 struct msr *msrs_alloc(void);
222 void msrs_free(struct msr *msrs);
223 int msr_set_bit(u32 msr, u8 bit);
224 int msr_clear_bit(u32 msr, u8 bit);
225 
226 #ifdef CONFIG_SMP
227 int rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h);
228 int wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h);
229 int rdmsrl_on_cpu(unsigned int cpu, u32 msr_no, u64 *q);
230 int wrmsrl_on_cpu(unsigned int cpu, u32 msr_no, u64 q);
231 void rdmsr_on_cpus(const struct cpumask *mask, u32 msr_no, struct msr *msrs);
232 void wrmsr_on_cpus(const struct cpumask *mask, u32 msr_no, struct msr *msrs);
233 int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h);
234 int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h);
235 int rdmsrl_safe_on_cpu(unsigned int cpu, u32 msr_no, u64 *q);
236 int wrmsrl_safe_on_cpu(unsigned int cpu, u32 msr_no, u64 q);
237 int rdmsr_safe_regs_on_cpu(unsigned int cpu, u32 regs[8]);
238 int wrmsr_safe_regs_on_cpu(unsigned int cpu, u32 regs[8]);
239 #else  /*  CONFIG_SMP  */
240 static inline int rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h)
241 {
242 	rdmsr(msr_no, *l, *h);
243 	return 0;
244 }
245 static inline int wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
246 {
247 	wrmsr(msr_no, l, h);
248 	return 0;
249 }
250 static inline int rdmsrl_on_cpu(unsigned int cpu, u32 msr_no, u64 *q)
251 {
252 	rdmsrl(msr_no, *q);
253 	return 0;
254 }
255 static inline int wrmsrl_on_cpu(unsigned int cpu, u32 msr_no, u64 q)
256 {
257 	wrmsrl(msr_no, q);
258 	return 0;
259 }
260 static inline void rdmsr_on_cpus(const struct cpumask *m, u32 msr_no,
261 				struct msr *msrs)
262 {
263        rdmsr_on_cpu(0, msr_no, &(msrs[0].l), &(msrs[0].h));
264 }
265 static inline void wrmsr_on_cpus(const struct cpumask *m, u32 msr_no,
266 				struct msr *msrs)
267 {
268        wrmsr_on_cpu(0, msr_no, msrs[0].l, msrs[0].h);
269 }
270 static inline int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no,
271 				    u32 *l, u32 *h)
272 {
273 	return rdmsr_safe(msr_no, l, h);
274 }
275 static inline int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
276 {
277 	return wrmsr_safe(msr_no, l, h);
278 }
279 static inline int rdmsrl_safe_on_cpu(unsigned int cpu, u32 msr_no, u64 *q)
280 {
281 	return rdmsrl_safe(msr_no, q);
282 }
283 static inline int wrmsrl_safe_on_cpu(unsigned int cpu, u32 msr_no, u64 q)
284 {
285 	return wrmsrl_safe(msr_no, q);
286 }
287 static inline int rdmsr_safe_regs_on_cpu(unsigned int cpu, u32 regs[8])
288 {
289 	return rdmsr_safe_regs(regs);
290 }
291 static inline int wrmsr_safe_regs_on_cpu(unsigned int cpu, u32 regs[8])
292 {
293 	return wrmsr_safe_regs(regs);
294 }
295 #endif  /* CONFIG_SMP */
296 #endif /* __ASSEMBLY__ */
297 #endif /* _ASM_X86_MSR_H */
298