LXR linux/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
  23static 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
  35static void tegra20_cpufreq_put_supported_hw(void *opp_table)
  36{
  37        dev_pm_opp_put_supported_hw(opp_table);
  38}
  39
  40static void tegra20_cpufreq_dt_unregister(void *cpufreq_dt)
  41{
  42        platform_device_unregister(cpufreq_dt);
  43}
  44
  45static int tegra20_cpufreq_probe(struct platform_device *pdev)
  46{
  47        struct platform_device *cpufreq_dt;
  48        struct opp_table *opp_table;
  49        struct device *cpu_dev;
  50        u32 versions[2];
  51        int err;
  52
  53        if (!cpu0_node_has_opp_v2_prop()) {
  54                dev_err(&pdev->dev, "operating points not found\n");
  55                dev_err(&pdev->dev, "please update your device tree\n");
  56                return -ENODEV;
  57        }
  58
  59        if (of_machine_is_compatible("nvidia,tegra20")) {
  60                versions[0] = BIT(tegra_sku_info.cpu_process_id);
  61                versions[1] = BIT(tegra_sku_info.soc_speedo_id);
  62        } else {
  63                versions[0] = BIT(tegra_sku_info.cpu_process_id);
  64                versions[1] = BIT(tegra_sku_info.cpu_speedo_id);
  65        }
  66
  67        dev_info(&pdev->dev, "hardware version 0x%x 0x%x\n",
  68                 versions[0], versions[1]);
  69
  70        cpu_dev = get_cpu_device(0);
  71        if (WARN_ON(!cpu_dev))
  72                return -ENODEV;
  73
  74        opp_table = dev_pm_opp_set_supported_hw(cpu_dev, versions, 2);
  75        err = PTR_ERR_OR_ZERO(opp_table);
  76        if (err) {
  77                dev_err(&pdev->dev, "failed to set supported hw: %d\n", err);
  78                return err;
  79        }
  80
  81        err = devm_add_action_or_reset(&pdev->dev,
  82                                       tegra20_cpufreq_put_supported_hw,
  83                                       opp_table);
  84        if (err)
  85                return err;
  86
  87        cpufreq_dt = platform_device_register_simple("cpufreq-dt", -1, NULL, 0);
  88        err = PTR_ERR_OR_ZERO(cpufreq_dt);
  89        if (err) {
  90                dev_err(&pdev->dev,
  91                        "failed to create cpufreq-dt device: %d\n", err);
  92                return err;
  93        }
  94
  95        err = devm_add_action_or_reset(&pdev->dev,
  96                                       tegra20_cpufreq_dt_unregister,
  97                                       cpufreq_dt);
  98        if (err)
  99                return err;
 100
 101        return 0;
 102}
 103
 104static struct platform_driver tegra20_cpufreq_driver = {
 105        .probe          = tegra20_cpufreq_probe,
 106        .driver         = {
 107                .name   = "tegra20-cpufreq",
 108        },
 109};
 110module_platform_driver(tegra20_cpufreq_driver);
 111
 112MODULE_ALIAS("platform:tegra20-cpufreq");
 113MODULE_AUTHOR("Colin Cross <ccross@android.com>");
 114MODULE_DESCRIPTION("NVIDIA Tegra20 cpufreq driver");
 115MODULE_LICENSE("GPL");
 116