include/cpu.h

   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
  12 struct 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  */
  27 struct 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 */
  37 enum {
  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  */
  53 struct cpu_info {
  54         ulong cpu_freq;
  55         ulong features;
  56         uint address_width;
  57 };
  58
  59 struct 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 #define cpu_get_ops(dev)        ((struct cpu_ops *)(dev)->driver->ops)
 108
 109 /**
 110  * cpu_get_desc() - Get a description string for a CPU
 111  * @dev:        Device to check (UCLASS_CPU)
 112  * @buf:        Buffer to place string
 113  * @size:       Size of string space
 114  *
 115  * Return: 0 if OK, -ENOSPC if buffer is too small, other -ve on error
 116  */
 117 int cpu_get_desc(const struct udevice *dev, char *buf, int size);
 118
 119 /**
 120  * cpu_get_info() - Get information about a CPU
 121  * @dev:        Device to check (UCLASS_CPU)
 122  * @info:       Returns CPU info
 123  *
 124  * Return: 0 if OK, -ve on error
 125  */
 126 int cpu_get_info(const struct udevice *dev, struct cpu_info *info);
 127
 128 /**
 129  * cpu_get_count() - Get number of CPUs
 130  * @dev:        Device to check (UCLASS_CPU)
 131  *
 132  * Return: CPU count if OK, -ve on error
 133  */
 134 int cpu_get_count(const struct udevice *dev);
 135
 136 /**
 137  * cpu_get_vendor() - Get vendor name of a CPU
 138  * @dev:        Device to check (UCLASS_CPU)
 139  * @buf:        Buffer to place string
 140  * @size:       Size of string space
 141  *
 142  * Return: 0 if OK, -ENOSPC if buffer is too small, other -ve on error
 143  */
 144 int cpu_get_vendor(const struct udevice *dev, char *buf, int size);
 145
 146 /**
 147  * cpu_probe_all() - Probe all available CPUs
 148  *
 149  * Return: 0 if OK, -ve on error
 150  */
 151 int cpu_probe_all(void);
 152
 153 /**
 154  * cpu_is_current() - Check if the CPU that U-Boot is currently running from
 155  *
 156  * Return: 1 if yes, - 0 if not
 157  */
 158 int cpu_is_current(struct udevice *cpu);
 159
 160 /**
 161  * cpu_get_current_dev() - Get CPU udevice for current CPU
 162  *
 163  * Return: udevice if OK, - NULL on error
 164  */
 165 struct udevice *cpu_get_current_dev(void);
 166
 167 #endif