1b66370dbSMichael Roth /* SPDX-License-Identifier: GPL-2.0 */
2b66370dbSMichael Roth /*
3b66370dbSMichael Roth * CPUID-related helpers/definitions
4b66370dbSMichael Roth */
5b66370dbSMichael Roth
6b66370dbSMichael Roth #ifndef _ASM_X86_CPUID_H
7b66370dbSMichael Roth #define _ASM_X86_CPUID_H
8b66370dbSMichael Roth
9d8001690SBorislav Petkov #include <asm/string.h>
10d8001690SBorislav Petkov
11d8001690SBorislav Petkov struct cpuid_regs {
12d8001690SBorislav Petkov u32 eax, ebx, ecx, edx;
13d8001690SBorislav Petkov };
14d8001690SBorislav Petkov
15d8001690SBorislav Petkov enum cpuid_regs_idx {
16d8001690SBorislav Petkov CPUID_EAX = 0,
17d8001690SBorislav Petkov CPUID_EBX,
18d8001690SBorislav Petkov CPUID_ECX,
19d8001690SBorislav Petkov CPUID_EDX,
20d8001690SBorislav Petkov };
21d8001690SBorislav Petkov
22d8001690SBorislav Petkov #ifdef CONFIG_X86_32
23d8001690SBorislav Petkov extern int have_cpuid_p(void);
24d8001690SBorislav Petkov #else
have_cpuid_p(void)25d8001690SBorislav Petkov static inline int have_cpuid_p(void)
26d8001690SBorislav Petkov {
27d8001690SBorislav Petkov return 1;
28d8001690SBorislav Petkov }
29d8001690SBorislav Petkov #endif
native_cpuid(unsigned int * eax,unsigned int * ebx,unsigned int * ecx,unsigned int * edx)30d8001690SBorislav Petkov static inline void native_cpuid(unsigned int *eax, unsigned int *ebx,
31d8001690SBorislav Petkov unsigned int *ecx, unsigned int *edx)
32d8001690SBorislav Petkov {
33d8001690SBorislav Petkov /* ecx is often an input as well as an output. */
34d8001690SBorislav Petkov asm volatile("cpuid"
35d8001690SBorislav Petkov : "=a" (*eax),
36d8001690SBorislav Petkov "=b" (*ebx),
37d8001690SBorislav Petkov "=c" (*ecx),
38d8001690SBorislav Petkov "=d" (*edx)
39d8001690SBorislav Petkov : "0" (*eax), "2" (*ecx)
40d8001690SBorislav Petkov : "memory");
41d8001690SBorislav Petkov }
42d8001690SBorislav Petkov
43d8001690SBorislav Petkov #define native_cpuid_reg(reg) \
44d8001690SBorislav Petkov static inline unsigned int native_cpuid_##reg(unsigned int op) \
45d8001690SBorislav Petkov { \
46d8001690SBorislav Petkov unsigned int eax = op, ebx, ecx = 0, edx; \
47d8001690SBorislav Petkov \
48d8001690SBorislav Petkov native_cpuid(&eax, &ebx, &ecx, &edx); \
49d8001690SBorislav Petkov \
50d8001690SBorislav Petkov return reg; \
51d8001690SBorislav Petkov }
52d8001690SBorislav Petkov
53d8001690SBorislav Petkov /*
54d8001690SBorislav Petkov * Native CPUID functions returning a single datum.
55d8001690SBorislav Petkov */
56d8001690SBorislav Petkov native_cpuid_reg(eax)
native_cpuid_reg(ebx)57d8001690SBorislav Petkov native_cpuid_reg(ebx)
58d8001690SBorislav Petkov native_cpuid_reg(ecx)
59d8001690SBorislav Petkov native_cpuid_reg(edx)
60d8001690SBorislav Petkov
61d8001690SBorislav Petkov #ifdef CONFIG_PARAVIRT_XXL
62d8001690SBorislav Petkov #include <asm/paravirt.h>
63d8001690SBorislav Petkov #else
64d8001690SBorislav Petkov #define __cpuid native_cpuid
65d8001690SBorislav Petkov #endif
66d8001690SBorislav Petkov
67d8001690SBorislav Petkov /*
68d8001690SBorislav Petkov * Generic CPUID function
69d8001690SBorislav Petkov * clear %ecx since some cpus (Cyrix MII) do not set or clear %ecx
70d8001690SBorislav Petkov * resulting in stale register contents being returned.
71d8001690SBorislav Petkov */
72d8001690SBorislav Petkov static inline void cpuid(unsigned int op,
73d8001690SBorislav Petkov unsigned int *eax, unsigned int *ebx,
74d8001690SBorislav Petkov unsigned int *ecx, unsigned int *edx)
75d8001690SBorislav Petkov {
76d8001690SBorislav Petkov *eax = op;
77d8001690SBorislav Petkov *ecx = 0;
78d8001690SBorislav Petkov __cpuid(eax, ebx, ecx, edx);
79d8001690SBorislav Petkov }
80d8001690SBorislav Petkov
81d8001690SBorislav Petkov /* Some CPUID calls want 'count' to be placed in ecx */
cpuid_count(unsigned int op,int count,unsigned int * eax,unsigned int * ebx,unsigned int * ecx,unsigned int * edx)82d8001690SBorislav Petkov static inline void cpuid_count(unsigned int op, int count,
83d8001690SBorislav Petkov unsigned int *eax, unsigned int *ebx,
84d8001690SBorislav Petkov unsigned int *ecx, unsigned int *edx)
85d8001690SBorislav Petkov {
86d8001690SBorislav Petkov *eax = op;
87d8001690SBorislav Petkov *ecx = count;
88d8001690SBorislav Petkov __cpuid(eax, ebx, ecx, edx);
89d8001690SBorislav Petkov }
90d8001690SBorislav Petkov
91d8001690SBorislav Petkov /*
92d8001690SBorislav Petkov * CPUID functions returning a single datum
93d8001690SBorislav Petkov */
cpuid_eax(unsigned int op)94d8001690SBorislav Petkov static inline unsigned int cpuid_eax(unsigned int op)
95d8001690SBorislav Petkov {
96d8001690SBorislav Petkov unsigned int eax, ebx, ecx, edx;
97d8001690SBorislav Petkov
98d8001690SBorislav Petkov cpuid(op, &eax, &ebx, &ecx, &edx);
99d8001690SBorislav Petkov
100d8001690SBorislav Petkov return eax;
101d8001690SBorislav Petkov }
102d8001690SBorislav Petkov
cpuid_ebx(unsigned int op)103d8001690SBorislav Petkov static inline unsigned int cpuid_ebx(unsigned int op)
104d8001690SBorislav Petkov {
105d8001690SBorislav Petkov unsigned int eax, ebx, ecx, edx;
106d8001690SBorislav Petkov
107d8001690SBorislav Petkov cpuid(op, &eax, &ebx, &ecx, &edx);
108d8001690SBorislav Petkov
109d8001690SBorislav Petkov return ebx;
110d8001690SBorislav Petkov }
111d8001690SBorislav Petkov
cpuid_ecx(unsigned int op)112d8001690SBorislav Petkov static inline unsigned int cpuid_ecx(unsigned int op)
113d8001690SBorislav Petkov {
114d8001690SBorislav Petkov unsigned int eax, ebx, ecx, edx;
115d8001690SBorislav Petkov
116d8001690SBorislav Petkov cpuid(op, &eax, &ebx, &ecx, &edx);
117d8001690SBorislav Petkov
118d8001690SBorislav Petkov return ecx;
119d8001690SBorislav Petkov }
120d8001690SBorislav Petkov
cpuid_edx(unsigned int op)121d8001690SBorislav Petkov static inline unsigned int cpuid_edx(unsigned int op)
122d8001690SBorislav Petkov {
123d8001690SBorislav Petkov unsigned int eax, ebx, ecx, edx;
124d8001690SBorislav Petkov
125d8001690SBorislav Petkov cpuid(op, &eax, &ebx, &ecx, &edx);
126d8001690SBorislav Petkov
127d8001690SBorislav Petkov return edx;
128d8001690SBorislav Petkov }
129d8001690SBorislav Petkov
__cpuid_read(unsigned int leaf,unsigned int subleaf,u32 * regs)13043d86e3cSThomas Gleixner static inline void __cpuid_read(unsigned int leaf, unsigned int subleaf, u32 *regs)
13143d86e3cSThomas Gleixner {
13243d86e3cSThomas Gleixner regs[CPUID_EAX] = leaf;
13343d86e3cSThomas Gleixner regs[CPUID_ECX] = subleaf;
13443d86e3cSThomas Gleixner __cpuid(regs + CPUID_EAX, regs + CPUID_EBX, regs + CPUID_ECX, regs + CPUID_EDX);
13543d86e3cSThomas Gleixner }
13643d86e3cSThomas Gleixner
13743d86e3cSThomas Gleixner #define cpuid_subleaf(leaf, subleaf, regs) { \
13843d86e3cSThomas Gleixner static_assert(sizeof(*(regs)) == 16); \
13943d86e3cSThomas Gleixner __cpuid_read(leaf, subleaf, (u32 *)(regs)); \
14043d86e3cSThomas Gleixner }
14143d86e3cSThomas Gleixner
14243d86e3cSThomas Gleixner #define cpuid_leaf(leaf, regs) { \
14343d86e3cSThomas Gleixner static_assert(sizeof(*(regs)) == 16); \
14443d86e3cSThomas Gleixner __cpuid_read(leaf, 0, (u32 *)(regs)); \
14543d86e3cSThomas Gleixner }
14643d86e3cSThomas Gleixner
__cpuid_read_reg(unsigned int leaf,unsigned int subleaf,enum cpuid_regs_idx regidx,u32 * reg)14743d86e3cSThomas Gleixner static inline void __cpuid_read_reg(unsigned int leaf, unsigned int subleaf,
14843d86e3cSThomas Gleixner enum cpuid_regs_idx regidx, u32 *reg)
14943d86e3cSThomas Gleixner {
15043d86e3cSThomas Gleixner u32 regs[4];
15143d86e3cSThomas Gleixner
15243d86e3cSThomas Gleixner __cpuid_read(leaf, subleaf, regs);
15343d86e3cSThomas Gleixner *reg = regs[regidx];
15443d86e3cSThomas Gleixner }
15543d86e3cSThomas Gleixner
15643d86e3cSThomas Gleixner #define cpuid_subleaf_reg(leaf, subleaf, regidx, reg) { \
15743d86e3cSThomas Gleixner static_assert(sizeof(*(reg)) == 4); \
15843d86e3cSThomas Gleixner __cpuid_read_reg(leaf, subleaf, regidx, (u32 *)(reg)); \
15943d86e3cSThomas Gleixner }
16043d86e3cSThomas Gleixner
16143d86e3cSThomas Gleixner #define cpuid_leaf_reg(leaf, regidx, reg) { \
16243d86e3cSThomas Gleixner static_assert(sizeof(*(reg)) == 4); \
16343d86e3cSThomas Gleixner __cpuid_read_reg(leaf, 0, regidx, (u32 *)(reg)); \
16443d86e3cSThomas Gleixner }
16543d86e3cSThomas Gleixner
cpuid_function_is_indexed(u32 function)166b66370dbSMichael Roth static __always_inline bool cpuid_function_is_indexed(u32 function)
167b66370dbSMichael Roth {
168b66370dbSMichael Roth switch (function) {
169b66370dbSMichael Roth case 4:
170b66370dbSMichael Roth case 7:
171b66370dbSMichael Roth case 0xb:
172b66370dbSMichael Roth case 0xd:
173b66370dbSMichael Roth case 0xf:
174b66370dbSMichael Roth case 0x10:
175b66370dbSMichael Roth case 0x12:
176b66370dbSMichael Roth case 0x14:
177b66370dbSMichael Roth case 0x17:
178b66370dbSMichael Roth case 0x18:
179b66370dbSMichael Roth case 0x1d:
180b66370dbSMichael Roth case 0x1e:
181b66370dbSMichael Roth case 0x1f:
182*1c450ffeSTao Su case 0x24:
183b66370dbSMichael Roth case 0x8000001d:
184b66370dbSMichael Roth return true;
185b66370dbSMichael Roth }
186b66370dbSMichael Roth
187b66370dbSMichael Roth return false;
188b66370dbSMichael Roth }
189b66370dbSMichael Roth
190d8001690SBorislav Petkov #define for_each_possible_hypervisor_cpuid_base(function) \
191d8001690SBorislav Petkov for (function = 0x40000000; function < 0x40010000; function += 0x100)
192d8001690SBorislav Petkov
hypervisor_cpuid_base(const char * sig,uint32_t leaves)193d8001690SBorislav Petkov static inline uint32_t hypervisor_cpuid_base(const char *sig, uint32_t leaves)
194d8001690SBorislav Petkov {
195d8001690SBorislav Petkov uint32_t base, eax, signature[3];
196d8001690SBorislav Petkov
197d8001690SBorislav Petkov for_each_possible_hypervisor_cpuid_base(base) {
198d8001690SBorislav Petkov cpuid(base, &eax, &signature[0], &signature[1], &signature[2]);
199d8001690SBorislav Petkov
200416a33c9SAlexey Dobriyan /*
201416a33c9SAlexey Dobriyan * This must not compile to "call memcmp" because it's called
202416a33c9SAlexey Dobriyan * from PVH early boot code before instrumentation is set up
203416a33c9SAlexey Dobriyan * and memcmp() itself may be instrumented.
204416a33c9SAlexey Dobriyan */
205416a33c9SAlexey Dobriyan if (!__builtin_memcmp(sig, signature, 12) &&
206d8001690SBorislav Petkov (leaves == 0 || ((eax - base) >= leaves)))
207d8001690SBorislav Petkov return base;
208d8001690SBorislav Petkov }
209d8001690SBorislav Petkov
210d8001690SBorislav Petkov return 0;
211d8001690SBorislav Petkov }
212d8001690SBorislav Petkov
213b66370dbSMichael Roth #endif /* _ASM_X86_CPUID_H */
214