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"Das U-Boot" Source Tree
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#include <linux/types.h>
11
12struct udevice;
13
14/**
15 * struct cpu_plat - platform data for a CPU
16 * @cpu_id: Platform-specific way of identifying the CPU.
17 * @ucode_version: Microcode version, if CPU_FEAT_UCODE is set
18 * @device_id: Driver-defined device identifier
19 * @family: DMTF CPU Family identifier
20 * @id: DMTF CPU Processor identifier
21 * @timebase_freq: the current frequency at which the cpu timer timebase
22 * registers are updated (in Hz)
23 *
24 * This can be accessed with dev_get_parent_plat() for any UCLASS_CPU
25 * device.
26 */
27struct cpu_plat {
28 int cpu_id;
29 int ucode_version;
30 ulong device_id;
31 u16 family;
32 u32 id[2];
33 u32 timebase_freq;
34};
35
36/* CPU features - mostly just a placeholder for now */
37enum {
38 CPU_FEAT_L1_CACHE = 0, /* Supports level 1 cache */
39 CPU_FEAT_MMU = 1, /* Supports virtual memory */
40 CPU_FEAT_UCODE = 2, /* Requires/uses microcode */
41 CPU_FEAT_DEVICE_ID = 3, /* Provides a device ID */
42
43 CPU_FEAT_COUNT,
44};
45
46/**
47 * struct cpu_info - Information about a CPU
48 *
49 * @cpu_freq: Current CPU frequency in Hz
50 * @features: Flags for supported CPU features
51 * @address_width: Width of the CPU address space in bits (e.g. 32)
52 */
53struct cpu_info {
54 ulong cpu_freq;
55 ulong features;
56 uint address_width;
57};
58
59struct cpu_ops {
60 /**
61 * get_desc() - Get a description string for a CPU
62 *
63 * @dev: Device to check (UCLASS_CPU)
64 * @buf: Buffer to place string
65 * @size: Size of string space
66 * @return 0 if OK, -ENOSPC if buffer is too small, other -ve on error
67 */
68 int (*get_desc)(const struct udevice *dev, char *buf, int size);
69
70 /**
71 * get_info() - Get information about a CPU
72 *
73 * @dev: Device to check (UCLASS_CPU)
74 * @info: Returns CPU info
75 * @return 0 if OK, -ve on error
76 */
77 int (*get_info)(const struct udevice *dev, struct cpu_info *info);
78
79 /**
80 * get_count() - Get number of CPUs
81 *
82 * @dev: Device to check (UCLASS_CPU)
83 * @return CPU count if OK, -ve on error
84 */
85 int (*get_count)(const struct udevice *dev);
86
87 /**
88 * get_vendor() - Get vendor name of a CPU
89 *
90 * @dev: Device to check (UCLASS_CPU)
91 * @buf: Buffer to place string
92 * @size: Size of string space
93 * @return 0 if OK, -ENOSPC if buffer is too small, other -ve on error
94 */
95 int (*get_vendor)(const struct udevice *dev, char *buf, int size);
96
97 /**
98 * is_current() - Check if the CPU that U-Boot is currently running from
99 *
100 * @dev: Device to check (UCLASS_CPU)
101 * @return 1 if the CPU that U-Boot is currently running from, 0
102 * if not.
103 */
104 int (*is_current)(struct udevice *dev);
105
106 /**
107 * release_core() - Relase a CPU core to the given address to run application
108 *
109 * @dev: Device to check (UCLASS_CPU)
110 * @addr: Address to relese the CPU core
111 * @return 0 if OK, -ve on error
112 */
113 int (*release_core)(const struct udevice *dev, phys_addr_t addr);
114};
115
116#define cpu_get_ops(dev) ((struct cpu_ops *)(dev)->driver->ops)
117
118/**
119 * cpu_get_desc() - Get a description string for a CPU
120 * @dev: Device to check (UCLASS_CPU)
121 * @buf: Buffer to place string
122 * @size: Size of string space
123 *
124 * Return: 0 if OK, -ENOSPC if buffer is too small, other -ve on error
125 */
126int cpu_get_desc(const struct udevice *dev, char *buf, int size);
127
128/**
129 * cpu_get_info() - Get information about a CPU
130 * @dev: Device to check (UCLASS_CPU)
131 * @info: Returns CPU info
132 *
133 * Return: 0 if OK, -ve on error
134 */
135int cpu_get_info(const struct udevice *dev, struct cpu_info *info);
136
137/**
138 * cpu_get_count() - Get number of CPUs
139 * @dev: Device to check (UCLASS_CPU)
140 *
141 * Return: CPU count if OK, -ve on error
142 */
143int cpu_get_count(const struct udevice *dev);
144
145/**
146 * cpu_get_vendor() - Get vendor name of a CPU
147 * @dev: Device to check (UCLASS_CPU)
148 * @buf: Buffer to place string
149 * @size: Size of string space
150 *
151 * Return: 0 if OK, -ENOSPC if buffer is too small, other -ve on error
152 */
153int cpu_get_vendor(const struct udevice *dev, char *buf, int size);
154
155/**
156 * cpu_probe_all() - Probe all available CPUs
157 *
158 * Return: 0 if OK, -ve on error
159 */
160int cpu_probe_all(void);
161
162/**
163 * cpu_is_current() - Check if the CPU that U-Boot is currently running from
164 *
165 * Return: 1 if yes, - 0 if not
166 */
167int cpu_is_current(struct udevice *cpu);
168
169/**
170 * cpu_get_current_dev() - Get CPU udevice for current CPU
171 *
172 * Return: udevice if OK, - NULL on error
173 */
174struct udevice *cpu_get_current_dev(void);
175
176/**
177 * cpu_release_core() - Relase a CPU core to the given address to run application
178 *
179 * @return 0 if OK, -ve on error
180 */
181int cpu_release_core(const struct udevice *dev, phys_addr_t addr);
182
183/**
184 * cpu_phys_address_size() - Get the physical-address size for the CPU
185 *
186 * x86 CPUs have a setting which indicates how many bits of address space are
187 * available on the CPU. This is 32 for older CPUs but newer ones may support 36
188 * or more.
189 *
190 * For non-x86 CPUs the result may simply be 32 for 32-bit CPUS or 64 for 64-bit
191 *
192 * Return: address size (typically 32 or 36)
193 */
194int cpu_phys_address_size(void);
195
196#endif