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 void tegra20_cpufreq_put_supported_hw(void *opp_table) 36 { 37 dev_pm_opp_put_supported_hw(opp_table); 38 } 39 40 static void tegra20_cpufreq_dt_unregister(void *cpufreq_dt) 41 { 42 platform_device_unregister(cpufreq_dt); 43 } 44 45 static 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 } 103 104 static struct platform_driver tegra20_cpufreq_driver = { 105 .probe = tegra20_cpufreq_probe, 106 .driver = { 107 .name = "tegra20-cpufreq", 108 }, 109 }; 110 module_platform_driver(tegra20_cpufreq_driver); 111 112 MODULE_ALIAS("platform:tegra20-cpufreq"); 113 MODULE_AUTHOR("Colin Cross <ccross@android.com>"); 114 MODULE_DESCRIPTION("NVIDIA Tegra20 cpufreq driver"); 115 MODULE_LICENSE("GPL"); 116