drivers/cpu/at91_cpu.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2020 Microchip Technology Inc. and its subsidiaries
   4  *
   5  * Author: Claudiu Beznea <claudiu.beznea@microchip.com>
   6  */
   7
   8 #include <common.h>
   9 #include <cpu.h>
  10 #include <dm.h>
  11 #include <div64.h>
  12 #include <linux/clk-provider.h>
  13
  14 struct at91_cpu_plat {
  15         const char *name;
  16         ulong cpufreq_mhz;
  17         ulong mckfreq_mhz;
  18         ulong xtalfreq_mhz;
  19 };
  20
  21 extern char *get_cpu_name(void);
  22
  23 const char *at91_cpu_get_name(void)
  24 {
  25         return get_cpu_name();
  26 }
  27
  28 int at91_cpu_get_desc(const struct udevice *dev, char *buf, int size)
  29 {
  30         struct at91_cpu_plat *plat = dev_get_plat(dev);
  31
  32         snprintf(buf, size, "%s\n"
  33                  "Crystal frequency: %8lu MHz\n"
  34                  "CPU clock        : %8lu MHz\n"
  35                  "Master clock     : %8lu MHz\n",
  36                  plat->name, plat->xtalfreq_mhz, plat->cpufreq_mhz,
  37                  plat->mckfreq_mhz);
  38
  39         return 0;
  40 }
  41
  42 static int at91_cpu_get_info(const struct udevice *dev, struct cpu_info *info)
  43 {
  44         struct at91_cpu_plat *plat = dev_get_plat(dev);
  45
  46         info->cpu_freq = plat->cpufreq_mhz * 1000000;
  47         info->features = BIT(CPU_FEAT_L1_CACHE);
  48
  49         return 0;
  50 }
  51
  52 static int at91_cpu_get_count(const struct udevice *dev)
  53 {
  54         return 1;
  55 }
  56
  57 static int at91_cpu_get_vendor(const struct udevice *dev,  char *buf, int size)
  58 {
  59         snprintf(buf, size, "Microchip Technology Inc.");
  60
  61         return 0;
  62 }
  63
  64 static const struct cpu_ops at91_cpu_ops = {
  65         .get_desc       = at91_cpu_get_desc,
  66         .get_info       = at91_cpu_get_info,
  67         .get_count      = at91_cpu_get_count,
  68         .get_vendor     = at91_cpu_get_vendor,
  69 };
  70
  71 static const struct udevice_id at91_cpu_ids[] = {
  72         { .compatible = "arm,cortex-a7" },
  73         { .compatible = "arm,arm926ej-s" },
  74         { /* Sentinel. */ }
  75 };
  76
  77 static int at91_cpu_probe(struct udevice *dev)
  78 {
  79         struct at91_cpu_plat *plat = dev_get_plat(dev);
  80         struct clk clk;
  81         ulong rate;
  82         int ret;
  83
  84         ret = clk_get_by_index(dev, 0, &clk);
  85         if (ret)
  86                 return ret;
  87
  88         rate  = clk_get_rate(&clk);
  89         if (!rate)
  90                 return -ENOTSUPP;
  91         plat->cpufreq_mhz = DIV_ROUND_CLOSEST_ULL(rate, 1000000);
  92
  93         ret = clk_get_by_index(dev, 1, &clk);
  94         if (ret)
  95                 return ret;
  96
  97         rate = clk_get_rate(&clk);
  98         if (!rate)
  99                 return -ENOTSUPP;
 100         plat->mckfreq_mhz = DIV_ROUND_CLOSEST_ULL(rate, 1000000);
 101
 102         ret = clk_get_by_index(dev, 2, &clk);
 103         if (ret)
 104                 return ret;
 105
 106         rate = clk_get_rate(&clk);
 107         if (!rate)
 108                 return -ENOTSUPP;
 109         plat->xtalfreq_mhz = DIV_ROUND_CLOSEST_ULL(rate, 1000000);
 110
 111         plat->name = get_cpu_name();
 112
 113         return 0;
 114 }
 115
 116 U_BOOT_DRIVER(cpu_at91_drv) = {
 117         .name           = "at91-cpu",
 118         .id             = UCLASS_CPU,
 119         .of_match       = at91_cpu_ids,
 120         .ops            = &at91_cpu_ops,
 121         .probe          = at91_cpu_probe,
 122         .plat_auto      = sizeof(struct at91_cpu_plat),
 123         .flags          = DM_FLAG_PRE_RELOC,
 124 };