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 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 83 err_put_supported_hw: 84 dev_pm_opp_put_supported_hw(opp_table); 85 86 return err; 87 } 88 89 static 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 } 103 104 static struct platform_driver tegra20_cpufreq_driver = { 105 .probe = tegra20_cpufreq_probe, 106 .remove = tegra20_cpufreq_remove, 107 .driver = { 108 .name = "tegra20-cpufreq", 109 }, 110 }; 111 module_platform_driver(tegra20_cpufreq_driver); 112 113 MODULE_ALIAS("platform:tegra20-cpufreq"); 114 MODULE_AUTHOR("Colin Cross <ccross@android.com>"); 115 MODULE_DESCRIPTION("NVIDIA Tegra20 cpufreq driver"); 116 MODULE_LICENSE("GPL"); 117