projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 8def3103 SH |
1 | /* |
| 2 | * System Control and Power Interface (SCPI) based CPUFreq Interface driver | |
| 3 | * | |
| 4 | * It provides necessary ops to arm_big_little cpufreq driver. | |
| 5 | * | |
| 6 | * Copyright (C) 2015 ARM Ltd. | |
| 7 | * Sudeep Holla <sudeep.holla@arm.com> | |
| 8 | * | |
| 9 | * This program is free software; you can redistribute it and/or modify | |
| 10 | * it under the terms of the GNU General Public License version 2 as | |
| 11 | * published by the Free Software Foundation. | |
| 12 | * | |
| 13 | * This program is distributed "as is" WITHOUT ANY WARRANTY of any | |
| 14 | * kind, whether express or implied; without even the implied warranty | |
| 15 | * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
| 16 | * GNU General Public License for more details. | |
| 17 | */ | |
| 18 | ||
| 19 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt | |
| 20 | ||
| d9975b0b | 21 | #include <linux/cpu.h> |
| 8def3103 SH |
22 | #include <linux/cpufreq.h> |
| 23 | #include <linux/module.h> | |
| 24 | #include <linux/platform_device.h> | |
| 25 | #include <linux/pm_opp.h> | |
| 26 | #include <linux/scpi_protocol.h> | |
| 27 | #include <linux/types.h> | |
| 28 | ||
| 29 | #include "arm_big_little.h" | |
| 30 | ||
| 31 | static struct scpi_ops *scpi_ops; | |
| 32 | ||
| 33 | static struct scpi_dvfs_info *scpi_get_dvfs_info(struct device *cpu_dev) | |
| 34 | { | |
| a7def561 | 35 | int domain = topology_physical_package_id(cpu_dev->id); |
| 8def3103 SH |
36 | |
| 37 | if (domain < 0) | |
| 38 | return ERR_PTR(-EINVAL); | |
| 39 | return scpi_ops->dvfs_get_info(domain); | |
| 40 | } | |
| 41 | ||
| d9975b0b | 42 | static int scpi_get_transition_latency(struct device *cpu_dev) |
| 8def3103 | 43 | { |
| d9975b0b SH |
44 | struct scpi_dvfs_info *info = scpi_get_dvfs_info(cpu_dev); |
| 45 | ||
| 46 | if (IS_ERR(info)) | |
| 47 | return PTR_ERR(info); | |
| 48 | return info->latency; | |
| 49 | } | |
| 50 | ||
| 51 | static int scpi_init_opp_table(const struct cpumask *cpumask) | |
| 52 | { | |
| 53 | int idx, ret; | |
| 8def3103 | 54 | struct scpi_opp *opp; |
| d9975b0b | 55 | struct device *cpu_dev = get_cpu_device(cpumask_first(cpumask)); |
| 8def3103 SH |
56 | struct scpi_dvfs_info *info = scpi_get_dvfs_info(cpu_dev); |
| 57 | ||
| 58 | if (IS_ERR(info)) | |
| 59 | return PTR_ERR(info); | |
| 60 | ||
| 61 | if (!info->opps) | |
| 62 | return -EIO; | |
| 63 | ||
| 64 | for (opp = info->opps, idx = 0; idx < info->count; idx++, opp++) { | |
| d9975b0b | 65 | ret = dev_pm_opp_add(cpu_dev, opp->freq, opp->m_volt * 1000); |
| 8def3103 SH |
66 | if (ret) { |
| 67 | dev_warn(cpu_dev, "failed to add opp %uHz %umV\n", | |
| 68 | opp->freq, opp->m_volt); | |
| 69 | while (idx-- > 0) | |
| 70 | dev_pm_opp_remove(cpu_dev, (--opp)->freq); | |
| 71 | return ret; | |
| 72 | } | |
| 73 | } | |
| 8def3103 | 74 | |
| d9975b0b SH |
75 | ret = dev_pm_opp_set_sharing_cpus(cpu_dev, cpumask); |
| 76 | if (ret) | |
| 77 | dev_err(cpu_dev, "%s: failed to mark OPPs as shared: %d\n", | |
| 78 | __func__, ret); | |
| 79 | return ret; | |
| 8def3103 SH |
80 | } |
| 81 | ||
| 82 | static struct cpufreq_arm_bL_ops scpi_cpufreq_ops = { | |
| 83 | .name = "scpi", | |
| 84 | .get_transition_latency = scpi_get_transition_latency, | |
| 85 | .init_opp_table = scpi_init_opp_table, | |
| d9975b0b | 86 | .free_opp_table = dev_pm_opp_cpumask_remove_table, |
| 8def3103 SH |
87 | }; |
| 88 | ||
| 89 | static int scpi_cpufreq_probe(struct platform_device *pdev) | |
| 90 | { | |
| 91 | scpi_ops = get_scpi_ops(); | |
| 92 | if (!scpi_ops) | |
| 93 | return -EIO; | |
| 94 | ||
| 95 | return bL_cpufreq_register(&scpi_cpufreq_ops); | |
| 96 | } | |
| 97 | ||
| 98 | static int scpi_cpufreq_remove(struct platform_device *pdev) | |
| 99 | { | |
| 100 | bL_cpufreq_unregister(&scpi_cpufreq_ops); | |
| 101 | scpi_ops = NULL; | |
| 102 | return 0; | |
| 103 | } | |
| 104 | ||
| 105 | static struct platform_driver scpi_cpufreq_platdrv = { | |
| 106 | .driver = { | |
| 107 | .name = "scpi-cpufreq", | |
| 8def3103 SH |
108 | }, |
| 109 | .probe = scpi_cpufreq_probe, | |
| 110 | .remove = scpi_cpufreq_remove, | |
| 111 | }; | |
| 112 | module_platform_driver(scpi_cpufreq_platdrv); | |
| 113 | ||
| 114 | MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>"); | |
| 115 | MODULE_DESCRIPTION("ARM SCPI CPUFreq interface driver"); | |
| 116 | MODULE_LICENSE("GPL v2"); |