xref: /openbmc/u-boot/arch/x86/include/asm/cpu.h (revision 909bd6d9)
1 /*
2  * Copyright (c) 2014 The Chromium OS Authors.
3  *
4  * Part of this file is adapted from coreboot
5  * src/arch/x86/include/arch/cpu.h and
6  * src/arch/x86/lib/cpu.c
7  *
8  * SPDX-License-Identifier:	GPL-2.0+
9  */
10 
11 #ifndef _ASM_CPU_H
12 #define _ASM_CPU_H
13 
14 enum {
15 	X86_VENDOR_INVALID = 0,
16 	X86_VENDOR_INTEL,
17 	X86_VENDOR_CYRIX,
18 	X86_VENDOR_AMD,
19 	X86_VENDOR_UMC,
20 	X86_VENDOR_NEXGEN,
21 	X86_VENDOR_CENTAUR,
22 	X86_VENDOR_RISE,
23 	X86_VENDOR_TRANSMETA,
24 	X86_VENDOR_NSC,
25 	X86_VENDOR_SIS,
26 	X86_VENDOR_ANY = 0xfe,
27 	X86_VENDOR_UNKNOWN = 0xff
28 };
29 
30 struct cpuid_result {
31 	uint32_t eax;
32 	uint32_t ebx;
33 	uint32_t ecx;
34 	uint32_t edx;
35 };
36 
37 /*
38  * Generic CPUID function
39  */
40 static inline struct cpuid_result cpuid(int op)
41 {
42 	struct cpuid_result result;
43 	asm volatile(
44 		"mov %%ebx, %%edi;"
45 		"cpuid;"
46 		"mov %%ebx, %%esi;"
47 		"mov %%edi, %%ebx;"
48 		: "=a" (result.eax),
49 		  "=S" (result.ebx),
50 		  "=c" (result.ecx),
51 		  "=d" (result.edx)
52 		: "0" (op)
53 		: "edi");
54 	return result;
55 }
56 
57 /*
58  * Generic Extended CPUID function
59  */
60 static inline struct cpuid_result cpuid_ext(int op, unsigned ecx)
61 {
62 	struct cpuid_result result;
63 	asm volatile(
64 		"mov %%ebx, %%edi;"
65 		"cpuid;"
66 		"mov %%ebx, %%esi;"
67 		"mov %%edi, %%ebx;"
68 		: "=a" (result.eax),
69 		  "=S" (result.ebx),
70 		  "=c" (result.ecx),
71 		  "=d" (result.edx)
72 		: "0" (op), "2" (ecx)
73 		: "edi");
74 	return result;
75 }
76 
77 /*
78  * CPUID functions returning a single datum
79  */
80 static inline unsigned int cpuid_eax(unsigned int op)
81 {
82 	unsigned int eax;
83 
84 	__asm__("mov %%ebx, %%edi;"
85 		"cpuid;"
86 		"mov %%edi, %%ebx;"
87 		: "=a" (eax)
88 		: "0" (op)
89 		: "ecx", "edx", "edi");
90 	return eax;
91 }
92 
93 static inline unsigned int cpuid_ebx(unsigned int op)
94 {
95 	unsigned int eax, ebx;
96 
97 	__asm__("mov %%ebx, %%edi;"
98 		"cpuid;"
99 		"mov %%ebx, %%esi;"
100 		"mov %%edi, %%ebx;"
101 		: "=a" (eax), "=S" (ebx)
102 		: "0" (op)
103 		: "ecx", "edx", "edi");
104 	return ebx;
105 }
106 
107 static inline unsigned int cpuid_ecx(unsigned int op)
108 {
109 	unsigned int eax, ecx;
110 
111 	__asm__("mov %%ebx, %%edi;"
112 		"cpuid;"
113 		"mov %%edi, %%ebx;"
114 		: "=a" (eax), "=c" (ecx)
115 		: "0" (op)
116 		: "edx", "edi");
117 	return ecx;
118 }
119 
120 static inline unsigned int cpuid_edx(unsigned int op)
121 {
122 	unsigned int eax, edx;
123 
124 	__asm__("mov %%ebx, %%edi;"
125 		"cpuid;"
126 		"mov %%edi, %%ebx;"
127 		: "=a" (eax), "=d" (edx)
128 		: "0" (op)
129 		: "ecx", "edi");
130 	return edx;
131 }
132 
133 /* Standard macro to see if a specific flag is changeable */
134 static inline int flag_is_changeable_p(uint32_t flag)
135 {
136 	uint32_t f1, f2;
137 
138 	asm(
139 		"pushfl\n\t"
140 		"pushfl\n\t"
141 		"popl %0\n\t"
142 		"movl %0,%1\n\t"
143 		"xorl %2,%0\n\t"
144 		"pushl %0\n\t"
145 		"popfl\n\t"
146 		"pushfl\n\t"
147 		"popl %0\n\t"
148 		"popfl\n\t"
149 		: "=&r" (f1), "=&r" (f2)
150 		: "ir" (flag));
151 	return ((f1^f2) & flag) != 0;
152 }
153 
154 static inline void mfence(void)
155 {
156 	__asm__ __volatile__("mfence" : : : "memory");
157 }
158 
159 /**
160  * cpu_enable_paging_pae() - Enable PAE-paging
161  *
162  * @cr3:	Value to set in cr3 (PDPT or PML4T)
163  */
164 void cpu_enable_paging_pae(ulong cr3);
165 
166 /**
167  * cpu_disable_paging_pae() - Disable paging and PAE
168  */
169 void cpu_disable_paging_pae(void);
170 
171 /**
172  * cpu_has_64bit() - Check if the CPU has 64-bit support
173  *
174  * @return 1 if this CPU supports long mode (64-bit), 0 if not
175  */
176 int cpu_has_64bit(void);
177 
178 /**
179  * cpu_vendor_name() - Get CPU vendor name
180  *
181  * @vendor:	CPU vendor enumeration number
182  *
183  * @return:	Address to hold the CPU vendor name string
184  */
185 const char *cpu_vendor_name(int vendor);
186 
187 #define CPU_MAX_NAME_LEN	49
188 
189 /**
190  * cpu_get_name() - Get the name of the current cpu
191  *
192  * @name: Place to put name, which must be CPU_MAX_NAME_LEN bytes including
193  * @return pointer to name, which will likely be a few bytes after the start
194  * of @name
195  * \0 terminator
196  */
197 char *cpu_get_name(char *name);
198 
199 /**
200  *
201 * x86_cpu_get_desc() - Get a description string for an x86 CPU
202 *
203 * This uses cpu_get_name() and is suitable to use as the get_desc() method for
204 * the CPU uclass.
205 *
206 * @dev:		Device to check (UCLASS_CPU)
207 * @buf:		Buffer to place string
208 * @size:	Size of string space
209 * @return 0 if OK, -ENOSPC if buffer is too small, other -ve on error
210 */
211 int x86_cpu_get_desc(struct udevice *dev, char *buf, int size);
212 
213 /**
214  * cpu_call64() - Jump to a 64-bit Linux kernel (internal function)
215  *
216  * The kernel is uncompressed and the 64-bit entry point is expected to be
217  * at @target.
218  *
219  * This function is used internally - see cpu_jump_to_64bit() for a more
220  * useful function.
221  *
222  * @pgtable:	Address of 24KB area containing the page table
223  * @setup_base:	Pointer to the setup.bin information for the kernel
224  * @target:	Pointer to the start of the kernel image
225  */
226 void cpu_call64(ulong pgtable, ulong setup_base, ulong target);
227 
228 /**
229  * cpu_jump_to_64bit() - Jump to a 64-bit Linux kernel
230  *
231  * The kernel is uncompressed and the 64-bit entry point is expected to be
232  * at @target.
233  *
234  * @setup_base:	Pointer to the setup.bin information for the kernel
235  * @target:	Pointer to the start of the kernel image
236  */
237 int cpu_jump_to_64bit(ulong setup_base, ulong target);
238 
239 #endif
240