xref: /openbmc/u-boot/arch/x86/include/asm/msr.h (revision bf48fcb6)
1 /*
2  * Taken from the linux kernel file of the same name
3  *
4  * (C) Copyright 2012
5  * Graeme Russ, <graeme.russ@gmail.com>
6  *
7  * This program is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU General Public License as
9  * published by the Free Software Foundation; either version 2 of
10  * the License, or (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
20  * MA 02111-1307 USA
21  */
22 
23 #ifndef _ASM_X86_MSR_H
24 #define _ASM_X86_MSR_H
25 
26 #include <asm/msr-index.h>
27 
28 #ifndef __ASSEMBLY__
29 
30 #include <linux/types.h>
31 #include <linux/ioctl.h>
32 
33 #define X86_IOC_RDMSR_REGS	_IOWR('c', 0xA0, __u32[8])
34 #define X86_IOC_WRMSR_REGS	_IOWR('c', 0xA1, __u32[8])
35 
36 #ifdef __KERNEL__
37 
38 #include <asm/errno.h>
39 
40 struct msr {
41 	union {
42 		struct {
43 			u32 l;
44 			u32 h;
45 		};
46 		u64 q;
47 	};
48 };
49 
50 struct msr_info {
51 	u32 msr_no;
52 	struct msr reg;
53 	struct msr *msrs;
54 	int err;
55 };
56 
57 struct msr_regs_info {
58 	u32 *regs;
59 	int err;
60 };
61 
62 static inline unsigned long long native_read_tscp(unsigned int *aux)
63 {
64 	unsigned long low, high;
65 	asm volatile(".byte 0x0f,0x01,0xf9"
66 		     : "=a" (low), "=d" (high), "=c" (*aux));
67 	return low | ((u64)high << 32);
68 }
69 
70 /*
71  * both i386 and x86_64 returns 64-bit value in edx:eax, but gcc's "A"
72  * constraint has different meanings. For i386, "A" means exactly
73  * edx:eax, while for x86_64 it doesn't mean rdx:rax or edx:eax. Instead,
74  * it means rax *or* rdx.
75  */
76 #ifdef CONFIG_X86_64
77 #define DECLARE_ARGS(val, low, high)	unsigned low, high
78 #define EAX_EDX_VAL(val, low, high)	((low) | ((u64)(high) << 32))
79 #define EAX_EDX_ARGS(val, low, high)	"a" (low), "d" (high)
80 #define EAX_EDX_RET(val, low, high)	"=a" (low), "=d" (high)
81 #else
82 #define DECLARE_ARGS(val, low, high)	unsigned long long val
83 #define EAX_EDX_VAL(val, low, high)	(val)
84 #define EAX_EDX_ARGS(val, low, high)	"A" (val)
85 #define EAX_EDX_RET(val, low, high)	"=A" (val)
86 #endif
87 
88 static inline unsigned long long native_read_msr(unsigned int msr)
89 {
90 	DECLARE_ARGS(val, low, high);
91 
92 	asm volatile("rdmsr" : EAX_EDX_RET(val, low, high) : "c" (msr));
93 	return EAX_EDX_VAL(val, low, high);
94 }
95 
96 static inline void native_write_msr(unsigned int msr,
97 				    unsigned low, unsigned high)
98 {
99 	asm volatile("wrmsr" : : "c" (msr), "a"(low), "d" (high) : "memory");
100 }
101 
102 extern unsigned long long native_read_tsc(void);
103 
104 extern int native_rdmsr_safe_regs(u32 regs[8]);
105 extern int native_wrmsr_safe_regs(u32 regs[8]);
106 
107 static inline unsigned long long native_read_pmc(int counter)
108 {
109 	DECLARE_ARGS(val, low, high);
110 
111 	asm volatile("rdpmc" : EAX_EDX_RET(val, low, high) : "c" (counter));
112 	return EAX_EDX_VAL(val, low, high);
113 }
114 
115 #ifdef CONFIG_PARAVIRT
116 #include <asm/paravirt.h>
117 #else
118 #include <errno.h>
119 /*
120  * Access to machine-specific registers (available on 586 and better only)
121  * Note: the rd* operations modify the parameters directly (without using
122  * pointer indirection), this allows gcc to optimize better
123  */
124 
125 #define rdmsr(msr, val1, val2)					\
126 do {								\
127 	u64 __val = native_read_msr((msr));			\
128 	(void)((val1) = (u32)__val);				\
129 	(void)((val2) = (u32)(__val >> 32));			\
130 } while (0)
131 
132 static inline void wrmsr(unsigned msr, unsigned low, unsigned high)
133 {
134 	native_write_msr(msr, low, high);
135 }
136 
137 #define rdmsrl(msr, val)			\
138 	((val) = native_read_msr((msr)))
139 
140 #define wrmsrl(msr, val)						\
141 	native_write_msr((msr), (u32)((u64)(val)), (u32)((u64)(val) >> 32))
142 
143 /* rdmsr with exception handling */
144 #define rdmsr_safe(msr, p1, p2)					\
145 ({								\
146 	int __err;						\
147 	u64 __val = native_read_msr_safe((msr), &__err);	\
148 	(*p1) = (u32)__val;					\
149 	(*p2) = (u32)(__val >> 32);				\
150 	__err;							\
151 })
152 
153 static inline int rdmsrl_amd_safe(unsigned msr, unsigned long long *p)
154 {
155 	u32 gprs[8] = { 0 };
156 	int err;
157 
158 	gprs[1] = msr;
159 	gprs[7] = 0x9c5a203a;
160 
161 	err = native_rdmsr_safe_regs(gprs);
162 
163 	*p = gprs[0] | ((u64)gprs[2] << 32);
164 
165 	return err;
166 }
167 
168 static inline int wrmsrl_amd_safe(unsigned msr, unsigned long long val)
169 {
170 	u32 gprs[8] = { 0 };
171 
172 	gprs[0] = (u32)val;
173 	gprs[1] = msr;
174 	gprs[2] = val >> 32;
175 	gprs[7] = 0x9c5a203a;
176 
177 	return native_wrmsr_safe_regs(gprs);
178 }
179 
180 static inline int rdmsr_safe_regs(u32 regs[8])
181 {
182 	return native_rdmsr_safe_regs(regs);
183 }
184 
185 static inline int wrmsr_safe_regs(u32 regs[8])
186 {
187 	return native_wrmsr_safe_regs(regs);
188 }
189 
190 #define rdtscl(low)						\
191 	((low) = (u32)__native_read_tsc())
192 
193 #define rdtscll(val)						\
194 	((val) = __native_read_tsc())
195 
196 #define rdpmc(counter, low, high)			\
197 do {							\
198 	u64 _l = native_read_pmc((counter));		\
199 	(low)  = (u32)_l;				\
200 	(high) = (u32)(_l >> 32);			\
201 } while (0)
202 
203 #define rdtscp(low, high, aux)					\
204 do {                                                            \
205 	unsigned long long _val = native_read_tscp(&(aux));     \
206 	(low) = (u32)_val;                                      \
207 	(high) = (u32)(_val >> 32);                             \
208 } while (0)
209 
210 #define rdtscpll(val, aux) (val) = native_read_tscp(&(aux))
211 
212 #endif	/* !CONFIG_PARAVIRT */
213 
214 
215 #define checking_wrmsrl(msr, val) wrmsr_safe((msr), (u32)(val),		\
216 					     (u32)((val) >> 32))
217 
218 #define write_tsc(val1, val2) wrmsr(MSR_IA32_TSC, (val1), (val2))
219 
220 #define write_rdtscp_aux(val) wrmsr(MSR_TSC_AUX, (val), 0)
221 
222 struct msr *msrs_alloc(void);
223 void msrs_free(struct msr *msrs);
224 
225 #ifdef CONFIG_SMP
226 int rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h);
227 int wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h);
228 void rdmsr_on_cpus(const struct cpumask *mask, u32 msr_no, struct msr *msrs);
229 void wrmsr_on_cpus(const struct cpumask *mask, u32 msr_no, struct msr *msrs);
230 int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h);
231 int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h);
232 int rdmsr_safe_regs_on_cpu(unsigned int cpu, u32 regs[8]);
233 int wrmsr_safe_regs_on_cpu(unsigned int cpu, u32 regs[8]);
234 
235 #endif  /* CONFIG_SMP */
236 #endif /* __KERNEL__ */
237 #endif /* __ASSEMBLY__ */
238 #endif /* _ASM_X86_MSR_H */
239