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 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_property_present(np, "operating-points-v2")) 29 ret = true; 30 31 of_node_put(np); 32 return ret; 33 } 34 35 static void tegra20_cpufreq_put_supported_hw(void *opp_token) 36 { 37 dev_pm_opp_put_supported_hw((unsigned long) opp_token); 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 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 } 101 102 static struct platform_driver tegra20_cpufreq_driver = { 103 .probe = tegra20_cpufreq_probe, 104 .driver = { 105 .name = "tegra20-cpufreq", 106 }, 107 }; 108 module_platform_driver(tegra20_cpufreq_driver); 109 110 MODULE_ALIAS("platform:tegra20-cpufreq"); 111 MODULE_AUTHOR("Colin Cross <ccross@android.com>"); 112 MODULE_DESCRIPTION("NVIDIA Tegra20 cpufreq driver"); 113 MODULE_LICENSE("GPL"); 114