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");