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.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_property_present(np, "operating-points-v2"))
 29		ret = true;
 30
 31	of_node_put(np);
 32	return ret;
 33}
 34
 35static void tegra20_cpufreq_put_supported_hw(void *opp_token)
 36{
 37	dev_pm_opp_put_supported_hw((unsigned long) opp_token);
 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 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
102static struct platform_driver tegra20_cpufreq_driver = {
103	.probe		= tegra20_cpufreq_probe,
104	.driver		= {
105		.name	= "tegra20-cpufreq",
106	},
107};
108module_platform_driver(tegra20_cpufreq_driver);
109
110MODULE_ALIAS("platform:tegra20-cpufreq");
111MODULE_AUTHOR("Colin Cross <ccross@android.com>");
112MODULE_DESCRIPTION("NVIDIA Tegra20 cpufreq driver");
113MODULE_LICENSE("GPL");