xref: /openbmc/linux/arch/x86/include/asm/msr.h (revision e8e0929d)
1 #ifndef _ASM_X86_MSR_H
2 #define _ASM_X86_MSR_H
3 
4 #include <asm/msr-index.h>
5 
6 #ifndef __ASSEMBLY__
7 
8 #include <linux/types.h>
9 #include <linux/ioctl.h>
10 
11 #define X86_IOC_RDMSR_REGS	_IOWR('c', 0xA0, __u32[8])
12 #define X86_IOC_WRMSR_REGS	_IOWR('c', 0xA1, __u32[8])
13 
14 #ifdef __KERNEL__
15 
16 #include <asm/asm.h>
17 #include <asm/errno.h>
18 #include <asm/cpumask.h>
19 
20 struct msr {
21 	union {
22 		struct {
23 			u32 l;
24 			u32 h;
25 		};
26 		u64 q;
27 	};
28 };
29 
30 static inline unsigned long long native_read_tscp(unsigned int *aux)
31 {
32 	unsigned long low, high;
33 	asm volatile(".byte 0x0f,0x01,0xf9"
34 		     : "=a" (low), "=d" (high), "=c" (*aux));
35 	return low | ((u64)high << 32);
36 }
37 
38 /*
39  * both i386 and x86_64 returns 64-bit value in edx:eax, but gcc's "A"
40  * constraint has different meanings. For i386, "A" means exactly
41  * edx:eax, while for x86_64 it doesn't mean rdx:rax or edx:eax. Instead,
42  * it means rax *or* rdx.
43  */
44 #ifdef CONFIG_X86_64
45 #define DECLARE_ARGS(val, low, high)	unsigned low, high
46 #define EAX_EDX_VAL(val, low, high)	((low) | ((u64)(high) << 32))
47 #define EAX_EDX_ARGS(val, low, high)	"a" (low), "d" (high)
48 #define EAX_EDX_RET(val, low, high)	"=a" (low), "=d" (high)
49 #else
50 #define DECLARE_ARGS(val, low, high)	unsigned long long val
51 #define EAX_EDX_VAL(val, low, high)	(val)
52 #define EAX_EDX_ARGS(val, low, high)	"A" (val)
53 #define EAX_EDX_RET(val, low, high)	"=A" (val)
54 #endif
55 
56 static inline unsigned long long native_read_msr(unsigned int msr)
57 {
58 	DECLARE_ARGS(val, low, high);
59 
60 	asm volatile("rdmsr" : EAX_EDX_RET(val, low, high) : "c" (msr));
61 	return EAX_EDX_VAL(val, low, high);
62 }
63 
64 static inline unsigned long long native_read_msr_safe(unsigned int msr,
65 						      int *err)
66 {
67 	DECLARE_ARGS(val, low, high);
68 
69 	asm volatile("2: rdmsr ; xor %[err],%[err]\n"
70 		     "1:\n\t"
71 		     ".section .fixup,\"ax\"\n\t"
72 		     "3:  mov %[fault],%[err] ; jmp 1b\n\t"
73 		     ".previous\n\t"
74 		     _ASM_EXTABLE(2b, 3b)
75 		     : [err] "=r" (*err), EAX_EDX_RET(val, low, high)
76 		     : "c" (msr), [fault] "i" (-EIO));
77 	return EAX_EDX_VAL(val, low, high);
78 }
79 
80 static inline void native_write_msr(unsigned int msr,
81 				    unsigned low, unsigned high)
82 {
83 	asm volatile("wrmsr" : : "c" (msr), "a"(low), "d" (high) : "memory");
84 }
85 
86 /* Can be uninlined because referenced by paravirt */
87 notrace static inline int native_write_msr_safe(unsigned int msr,
88 					unsigned low, unsigned high)
89 {
90 	int err;
91 	asm volatile("2: wrmsr ; xor %[err],%[err]\n"
92 		     "1:\n\t"
93 		     ".section .fixup,\"ax\"\n\t"
94 		     "3:  mov %[fault],%[err] ; jmp 1b\n\t"
95 		     ".previous\n\t"
96 		     _ASM_EXTABLE(2b, 3b)
97 		     : [err] "=a" (err)
98 		     : "c" (msr), "0" (low), "d" (high),
99 		       [fault] "i" (-EIO)
100 		     : "memory");
101 	return err;
102 }
103 
104 extern unsigned long long native_read_tsc(void);
105 
106 extern int native_rdmsr_safe_regs(u32 regs[8]);
107 extern int native_wrmsr_safe_regs(u32 regs[8]);
108 
109 static __always_inline unsigned long long __native_read_tsc(void)
110 {
111 	DECLARE_ARGS(val, low, high);
112 
113 	asm volatile("rdtsc" : EAX_EDX_RET(val, low, high));
114 
115 	return EAX_EDX_VAL(val, low, high);
116 }
117 
118 static inline unsigned long long native_read_pmc(int counter)
119 {
120 	DECLARE_ARGS(val, low, high);
121 
122 	asm volatile("rdpmc" : EAX_EDX_RET(val, low, high) : "c" (counter));
123 	return EAX_EDX_VAL(val, low, high);
124 }
125 
126 #ifdef CONFIG_PARAVIRT
127 #include <asm/paravirt.h>
128 #else
129 #include <linux/errno.h>
130 /*
131  * Access to machine-specific registers (available on 586 and better only)
132  * Note: the rd* operations modify the parameters directly (without using
133  * pointer indirection), this allows gcc to optimize better
134  */
135 
136 #define rdmsr(msr, val1, val2)					\
137 do {								\
138 	u64 __val = native_read_msr((msr));			\
139 	(val1) = (u32)__val;					\
140 	(val2) = (u32)(__val >> 32);				\
141 } while (0)
142 
143 static inline void wrmsr(unsigned msr, unsigned low, unsigned high)
144 {
145 	native_write_msr(msr, low, high);
146 }
147 
148 #define rdmsrl(msr, val)			\
149 	((val) = native_read_msr((msr)))
150 
151 #define wrmsrl(msr, val)						\
152 	native_write_msr((msr), (u32)((u64)(val)), (u32)((u64)(val) >> 32))
153 
154 /* wrmsr with exception handling */
155 static inline int wrmsr_safe(unsigned msr, unsigned low, unsigned high)
156 {
157 	return native_write_msr_safe(msr, low, high);
158 }
159 
160 /* rdmsr with exception handling */
161 #define rdmsr_safe(msr, p1, p2)					\
162 ({								\
163 	int __err;						\
164 	u64 __val = native_read_msr_safe((msr), &__err);	\
165 	(*p1) = (u32)__val;					\
166 	(*p2) = (u32)(__val >> 32);				\
167 	__err;							\
168 })
169 
170 static inline int rdmsrl_safe(unsigned msr, unsigned long long *p)
171 {
172 	int err;
173 
174 	*p = native_read_msr_safe(msr, &err);
175 	return err;
176 }
177 
178 static inline int rdmsrl_amd_safe(unsigned msr, unsigned long long *p)
179 {
180 	u32 gprs[8] = { 0 };
181 	int err;
182 
183 	gprs[1] = msr;
184 	gprs[7] = 0x9c5a203a;
185 
186 	err = native_rdmsr_safe_regs(gprs);
187 
188 	*p = gprs[0] | ((u64)gprs[2] << 32);
189 
190 	return err;
191 }
192 
193 static inline int wrmsrl_amd_safe(unsigned msr, unsigned long long val)
194 {
195 	u32 gprs[8] = { 0 };
196 
197 	gprs[0] = (u32)val;
198 	gprs[1] = msr;
199 	gprs[2] = val >> 32;
200 	gprs[7] = 0x9c5a203a;
201 
202 	return native_wrmsr_safe_regs(gprs);
203 }
204 
205 static inline int rdmsr_safe_regs(u32 regs[8])
206 {
207 	return native_rdmsr_safe_regs(regs);
208 }
209 
210 static inline int wrmsr_safe_regs(u32 regs[8])
211 {
212 	return native_wrmsr_safe_regs(regs);
213 }
214 
215 #define rdtscl(low)						\
216 	((low) = (u32)__native_read_tsc())
217 
218 #define rdtscll(val)						\
219 	((val) = __native_read_tsc())
220 
221 #define rdpmc(counter, low, high)			\
222 do {							\
223 	u64 _l = native_read_pmc((counter));		\
224 	(low)  = (u32)_l;				\
225 	(high) = (u32)(_l >> 32);			\
226 } while (0)
227 
228 #define rdtscp(low, high, aux)					\
229 do {                                                            \
230 	unsigned long long _val = native_read_tscp(&(aux));     \
231 	(low) = (u32)_val;                                      \
232 	(high) = (u32)(_val >> 32);                             \
233 } while (0)
234 
235 #define rdtscpll(val, aux) (val) = native_read_tscp(&(aux))
236 
237 #endif	/* !CONFIG_PARAVIRT */
238 
239 
240 #define checking_wrmsrl(msr, val) wrmsr_safe((msr), (u32)(val),		\
241 					     (u32)((val) >> 32))
242 
243 #define write_tsc(val1, val2) wrmsr(0x10, (val1), (val2))
244 
245 #define write_rdtscp_aux(val) wrmsr(0xc0000103, (val), 0)
246 
247 #ifdef CONFIG_SMP
248 int rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h);
249 int wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h);
250 void rdmsr_on_cpus(const cpumask_t *mask, u32 msr_no, struct msr *msrs);
251 void wrmsr_on_cpus(const cpumask_t *mask, u32 msr_no, struct msr *msrs);
252 int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h);
253 int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h);
254 int rdmsr_safe_regs_on_cpu(unsigned int cpu, u32 regs[8]);
255 int wrmsr_safe_regs_on_cpu(unsigned int cpu, u32 regs[8]);
256 #else  /*  CONFIG_SMP  */
257 static inline int rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h)
258 {
259 	rdmsr(msr_no, *l, *h);
260 	return 0;
261 }
262 static inline int wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
263 {
264 	wrmsr(msr_no, l, h);
265 	return 0;
266 }
267 static inline void rdmsr_on_cpus(const cpumask_t *m, u32 msr_no,
268 				struct msr *msrs)
269 {
270        rdmsr_on_cpu(0, msr_no, &(msrs[0].l), &(msrs[0].h));
271 }
272 static inline void wrmsr_on_cpus(const cpumask_t *m, u32 msr_no,
273 				struct msr *msrs)
274 {
275        wrmsr_on_cpu(0, msr_no, msrs[0].l, msrs[0].h);
276 }
277 static inline int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no,
278 				    u32 *l, u32 *h)
279 {
280 	return rdmsr_safe(msr_no, l, h);
281 }
282 static inline int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
283 {
284 	return wrmsr_safe(msr_no, l, h);
285 }
286 static inline int rdmsr_safe_regs_on_cpu(unsigned int cpu, u32 regs[8])
287 {
288 	return rdmsr_safe_regs(regs);
289 }
290 static inline int wrmsr_safe_regs_on_cpu(unsigned int cpu, u32 regs[8])
291 {
292 	return wrmsr_safe_regs(regs);
293 }
294 #endif  /* CONFIG_SMP */
295 #endif /* __KERNEL__ */
296 #endif /* __ASSEMBLY__ */
297 #endif /* _ASM_X86_MSR_H */
298