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 int tegra20_cpufreq_probe(struct platform_device *pdev)
  36{
  37        struct platform_device *cpufreq_dt;
  38        struct opp_table *opp_table;
  39        struct device *cpu_dev;
  40        u32 versions[2];
  41        int err;
  42
  43        if (!cpu0_node_has_opp_v2_prop()) {
  44                dev_err(&pdev->dev, "operating points not found\n");
  45                dev_err(&pdev->dev, "please update your device tree\n");
  46                return -ENODEV;
  47        }
  48
  49        if (of_machine_is_compatible("nvidia,tegra20")) {
  50                versions[0] = BIT(tegra_sku_info.cpu_process_id);
  51                versions[1] = BIT(tegra_sku_info.soc_speedo_id);
  52        } else {
  53                versions[0] = BIT(tegra_sku_info.cpu_process_id);
  54                versions[1] = BIT(tegra_sku_info.cpu_speedo_id);
  55        }
  56
  57        dev_info(&pdev->dev, "hardware version 0x%x 0x%x\n",
  58                 versions[0], versions[1]);
  59
  60        cpu_dev = get_cpu_device(0);
  61        if (WARN_ON(!cpu_dev))
  62                return -ENODEV;
  63
  64        opp_table = dev_pm_opp_set_supported_hw(cpu_dev, versions, 2);
  65        err = PTR_ERR_OR_ZERO(opp_table);
  66        if (err) {
  67                dev_err(&pdev->dev, "failed to set supported hw: %d\n", err);
  68                return err;
  69        }
  70
  71        cpufreq_dt = platform_device_register_simple("cpufreq-dt", -1, NULL, 0);
  72        err = PTR_ERR_OR_ZERO(cpufreq_dt);
  73        if (err) {
  74                dev_err(&pdev->dev,
  75                        "failed to create cpufreq-dt device: %d\n", err);
  76                goto err_put_supported_hw;
  77        }
  78
  79        platform_set_drvdata(pdev, cpufreq_dt);
  80
  81        return 0;
  82
  83err_put_supported_hw:
  84        dev_pm_opp_put_supported_hw(opp_table);
  85
  86        return err;
  87}
  88
  89static int tegra20_cpufreq_remove(struct platform_device *pdev)
  90{
  91        struct platform_device *cpufreq_dt;
  92        struct opp_table *opp_table;
  93
  94        cpufreq_dt = platform_get_drvdata(pdev);
  95        platform_device_unregister(cpufreq_dt);
  96
  97        opp_table = dev_pm_opp_get_opp_table(get_cpu_device(0));
  98        dev_pm_opp_put_supported_hw(opp_table);
  99        dev_pm_opp_put_opp_table(opp_table);
 100
 101        return 0;
 102}
 103
 104static struct platform_driver tegra20_cpufreq_driver = {
 105        .probe          = tegra20_cpufreq_probe,
 106        .remove         = tegra20_cpufreq_remove,
 107        .driver         = {
 108                .name   = "tegra20-cpufreq",
 109        },
 110};
 111module_platform_driver(tegra20_cpufreq_driver);
 112
 113MODULE_ALIAS("platform:tegra20-cpufreq");
 114MODULE_AUTHOR("Colin Cross <ccross@android.com>");
 115MODULE_DESCRIPTION("NVIDIA Tegra20 cpufreq driver");
 116MODULE_LICENSE("GPL");
 117