1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3  * Copyright (c) 2015 Google, Inc
4  * Written by Simon Glass <sjg@chromium.org>
5  */
6 
7 #ifndef __CPU_H
8 #define __CPU_H
9 
10 struct udevice;
11 
12 /**
13  * struct cpu_plat - platform data for a CPU
14  * @cpu_id:	   Platform-specific way of identifying the CPU.
15  * @ucode_version: Microcode version, if CPU_FEAT_UCODE is set
16  * @device_id:     Driver-defined device identifier
17  * @family:        DMTF CPU Family identifier
18  * @id:            DMTF CPU Processor identifier
19  * @timebase_freq: the current frequency at which the cpu timer timebase
20  *		   registers are updated (in Hz)
21  *
22  * This can be accessed with dev_get_parent_plat() for any UCLASS_CPU
23  * device.
24  */
25 struct cpu_plat {
26 	int cpu_id;
27 	int ucode_version;
28 	ulong device_id;
29 	u16 family;
30 	u32 id[2];
31 	u32 timebase_freq;
32 };
33 
34 /* CPU features - mostly just a placeholder for now */
35 enum {
36 	CPU_FEAT_L1_CACHE	= 0,	/* Supports level 1 cache */
37 	CPU_FEAT_MMU		= 1,	/* Supports virtual memory */
38 	CPU_FEAT_UCODE		= 2,	/* Requires/uses microcode */
39 	CPU_FEAT_DEVICE_ID	= 3,	/* Provides a device ID */
40 
41 	CPU_FEAT_COUNT,
42 };
43 
44 /**
45  * struct cpu_info - Information about a CPU
46  *
47  * @cpu_freq:	Current CPU frequency in Hz
48  * @features:	Flags for supported CPU features
49  * @address_width:	Width of the CPU address space in bits (e.g. 32)
50  */
51 struct cpu_info {
52 	ulong cpu_freq;
53 	ulong features;
54 	uint address_width;
55 };
56 
57 struct cpu_ops {
58 	/**
59 	 * get_desc() - Get a description string for a CPU
60 	 *
61 	 * @dev:	Device to check (UCLASS_CPU)
62 	 * @buf:	Buffer to place string
63 	 * @size:	Size of string space
64 	 * @return 0 if OK, -ENOSPC if buffer is too small, other -ve on error
65 	 */
66 	int (*get_desc)(const struct udevice *dev, char *buf, int size);
67 
68 	/**
69 	 * get_info() - Get information about a CPU
70 	 *
71 	 * @dev:	Device to check (UCLASS_CPU)
72 	 * @info:	Returns CPU info
73 	 * @return 0 if OK, -ve on error
74 	 */
75 	int (*get_info)(const struct udevice *dev, struct cpu_info *info);
76 
77 	/**
78 	 * get_count() - Get number of CPUs
79 	 *
80 	 * @dev:	Device to check (UCLASS_CPU)
81 	 * @return CPU count if OK, -ve on error
82 	 */
83 	int (*get_count)(const struct udevice *dev);
84 
85 	/**
86 	 * get_vendor() - Get vendor name of a CPU
87 	 *
88 	 * @dev:	Device to check (UCLASS_CPU)
89 	 * @buf:	Buffer to place string
90 	 * @size:	Size of string space
91 	 * @return 0 if OK, -ENOSPC if buffer is too small, other -ve on error
92 	 */
93 	int (*get_vendor)(const struct udevice *dev, char *buf, int size);
94 
95 	/**
96 	 * is_current() - Check if the CPU that U-Boot is currently running from
97 	 *
98 	 * @dev:	Device to check (UCLASS_CPU)
99 	 * @return 1 if the CPU that U-Boot is currently running from, 0
100 	 *         if not.
101 	 */
102 	int (*is_current)(struct udevice *dev);
103 };
104 
105 #define cpu_get_ops(dev)        ((struct cpu_ops *)(dev)->driver->ops)
106 
107 /**
108  * cpu_get_desc() - Get a description string for a CPU
109  * @dev:	Device to check (UCLASS_CPU)
110  * @buf:	Buffer to place string
111  * @size:	Size of string space
112  *
113  * Return: 0 if OK, -ENOSPC if buffer is too small, other -ve on error
114  */
115 int cpu_get_desc(const struct udevice *dev, char *buf, int size);
116 
117 /**
118  * cpu_get_info() - Get information about a CPU
119  * @dev:	Device to check (UCLASS_CPU)
120  * @info:	Returns CPU info
121  *
122  * Return: 0 if OK, -ve on error
123  */
124 int cpu_get_info(const struct udevice *dev, struct cpu_info *info);
125 
126 /**
127  * cpu_get_count() - Get number of CPUs
128  * @dev:	Device to check (UCLASS_CPU)
129  *
130  * Return: CPU count if OK, -ve on error
131  */
132 int cpu_get_count(const struct udevice *dev);
133 
134 /**
135  * cpu_get_vendor() - Get vendor name of a CPU
136  * @dev:	Device to check (UCLASS_CPU)
137  * @buf:	Buffer to place string
138  * @size:	Size of string space
139  *
140  * Return: 0 if OK, -ENOSPC if buffer is too small, other -ve on error
141  */
142 int cpu_get_vendor(const struct udevice *dev, char *buf, int size);
143 
144 /**
145  * cpu_probe_all() - Probe all available CPUs
146  *
147  * Return: 0 if OK, -ve on error
148  */
149 int cpu_probe_all(void);
150 
151 /**
152  * cpu_is_current() - Check if the CPU that U-Boot is currently running from
153  *
154  * Return: 1 if yes, - 0 if not
155  */
156 int cpu_is_current(struct udevice *cpu);
157 
158 /**
159  * cpu_get_current_dev() - Get CPU udevice for current CPU
160  *
161  * Return: udevice if OK, - NULL on error
162  */
163 struct udevice *cpu_get_current_dev(void);
164 
165 #endif
166