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         { /* Sentinel. */ }
  74 };
  75
  76 static int at91_cpu_probe(struct udevice *dev)
  77 {
  78         struct at91_cpu_plat *plat = dev_get_plat(dev);
  79         struct clk clk;
  80         ulong rate;
  81         int ret;
  82
  83         ret = clk_get_by_index(dev, 0, &clk);
  84         if (ret)
  85                 return ret;
  86
  87         rate  = clk_get_rate(&clk);
  88         if (!rate)
  89                 return -ENOTSUPP;
  90         plat->cpufreq_mhz = DIV_ROUND_CLOSEST_ULL(rate, 1000000);
  91
  92         ret = clk_get_by_index(dev, 1, &clk);
  93         if (ret)
  94                 return ret;
  95
  96         rate = clk_get_rate(&clk);
  97         if (!rate)
  98                 return -ENOTSUPP;
  99         plat->mckfreq_mhz = DIV_ROUND_CLOSEST_ULL(rate, 1000000);
 100
 101         ret = clk_get_by_index(dev, 2, &clk);
 102         if (ret)
 103                 return ret;
 104
 105         rate = clk_get_rate(&clk);
 106         if (!rate)
 107                 return -ENOTSUPP;
 108         plat->xtalfreq_mhz = DIV_ROUND_CLOSEST_ULL(rate, 1000000);
 109
 110         plat->name = get_cpu_name();
 111
 112         return 0;
 113 }
 114
 115 U_BOOT_DRIVER(cpu_at91_drv) = {
 116         .name           = "at91-cpu",
 117         .id             = UCLASS_CPU,
 118         .of_match       = at91_cpu_ids,
 119         .ops            = &at91_cpu_ops,
 120         .probe          = at91_cpu_probe,
 121         .plat_auto      = sizeof(struct at91_cpu_plat),
 122         .flags          = DM_FLAG_PRE_RELOC,
 123 };