drivers/cpufreq/tegra20-cpufreq.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2010 Google, Inc.
   4  *
   5  * Author:
   6  *      Colin Cross <ccross@google.com>
   7  *      Based on arch/arm/plat-omap/cpu-omap.c, (C) 2005 Nokia Corporation
   8  */
   9
  10 #include <linux/bits.h>
  11 #include <linux/cpu.h>
  12 #include <linux/err.h>
  13 #include <linux/init.h>
  14 #include <linux/module.h>
  15 #include <linux/of_device.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/pm_opp.h>
  18 #include <linux/types.h>
  19
  20 #include <soc/tegra/common.h>
  21 #include <soc/tegra/fuse.h>
  22
  23 static bool cpu0_node_has_opp_v2_prop(void)
  24 {
  25         struct device_node *np = of_cpu_device_node_get(0);
  26         bool ret = false;
  27
  28         if (of_get_property(np, "operating-points-v2", NULL))
  29                 ret = true;
  30
  31         of_node_put(np);
  32         return ret;
  33 }
  34
  35 static void tegra20_cpufreq_put_supported_hw(void *opp_token)
  36 {
  37         dev_pm_opp_put_supported_hw((unsigned long) opp_token);
  38 }
  39
  40 static void tegra20_cpufreq_dt_unregister(void *cpufreq_dt)
  41 {
  42         platform_device_unregister(cpufreq_dt);
  43 }
  44
  45 static int tegra20_cpufreq_probe(struct platform_device *pdev)
  46 {
  47         struct platform_device *cpufreq_dt;
  48         struct device *cpu_dev;
  49         u32 versions[2];
  50         int err;
  51
  52         if (!cpu0_node_has_opp_v2_prop()) {
  53                 dev_err(&pdev->dev, "operating points not found\n");
  54                 dev_err(&pdev->dev, "please update your device tree\n");
  55                 return -ENODEV;
  56         }
  57
  58         if (of_machine_is_compatible("nvidia,tegra20")) {
  59                 versions[0] = BIT(tegra_sku_info.cpu_process_id);
  60                 versions[1] = BIT(tegra_sku_info.soc_speedo_id);
  61         } else {
  62                 versions[0] = BIT(tegra_sku_info.cpu_process_id);
  63                 versions[1] = BIT(tegra_sku_info.cpu_speedo_id);
  64         }
  65
  66         dev_info(&pdev->dev, "hardware version 0x%x 0x%x\n",
  67                  versions[0], versions[1]);
  68
  69         cpu_dev = get_cpu_device(0);
  70         if (WARN_ON(!cpu_dev))
  71                 return -ENODEV;
  72
  73         err = dev_pm_opp_set_supported_hw(cpu_dev, versions, 2);
  74         if (err < 0) {
  75                 dev_err(&pdev->dev, "failed to set supported hw: %d\n", err);
  76                 return err;
  77         }
  78
  79         err = devm_add_action_or_reset(&pdev->dev,
  80                                        tegra20_cpufreq_put_supported_hw,
  81                                        (void *)((unsigned long) err));
  82         if (err)
  83                 return err;
  84
  85         cpufreq_dt = platform_device_register_simple("cpufreq-dt", -1, NULL, 0);
  86         err = PTR_ERR_OR_ZERO(cpufreq_dt);
  87         if (err) {
  88                 dev_err(&pdev->dev,
  89                         "failed to create cpufreq-dt device: %d\n", err);
  90                 return err;
  91         }
  92
  93         err = devm_add_action_or_reset(&pdev->dev,
  94                                        tegra20_cpufreq_dt_unregister,
  95                                        cpufreq_dt);
  96         if (err)
  97                 return err;
  98
  99         return 0;
 100 }
 101
 102 static struct platform_driver tegra20_cpufreq_driver = {
 103         .probe          = tegra20_cpufreq_probe,
 104         .driver         = {
 105                 .name   = "tegra20-cpufreq",
 106         },
 107 };
 108 module_platform_driver(tegra20_cpufreq_driver);
 109
 110 MODULE_ALIAS("platform:tegra20-cpufreq");
 111 MODULE_AUTHOR("Colin Cross <ccross@android.com>");
 112 MODULE_DESCRIPTION("NVIDIA Tegra20 cpufreq driver");
 113 MODULE_LICENSE("GPL");