thermal/intel/intel_soc_dts_thermal.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  * intel_soc_dts_thermal.c
0004  * Copyright (c) 2014, Intel Corporation.
0005  */
0006
0007 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
0008
0009 #include <linux/acpi.h>
0010 #include <linux/module.h>
0011 #include <linux/interrupt.h>
0012 #include <asm/cpu_device_id.h>
0013 #include <asm/intel-family.h>
0014 #include "intel_soc_dts_iosf.h"
0015
0016 #define CRITICAL_OFFSET_FROM_TJ_MAX 5000
0017
0018 static int crit_offset = CRITICAL_OFFSET_FROM_TJ_MAX;
0019 module_param(crit_offset, int, 0644);
0020 MODULE_PARM_DESC(crit_offset,
0021     "Critical Temperature offset from tj max in millidegree Celsius.");
0022
0023 /* IRQ 86 is a fixed APIC interrupt for BYT DTS Aux threshold notifications */
0024 #define BYT_SOC_DTS_APIC_IRQ    86
0025
0026 static int soc_dts_thres_gsi;
0027 static int soc_dts_thres_irq;
0028 static struct intel_soc_dts_sensors *soc_dts;
0029
0030 static irqreturn_t soc_irq_thread_fn(int irq, void *dev_data)
0031 {
0032     pr_debug("proc_thermal_interrupt\n");
0033     intel_soc_dts_iosf_interrupt_handler(soc_dts);
0034
0035     return IRQ_HANDLED;
0036 }
0037
0038 static const struct x86_cpu_id soc_thermal_ids[] = {
0039     X86_MATCH_INTEL_FAM6_MODEL(ATOM_SILVERMONT, BYT_SOC_DTS_APIC_IRQ),
0040     {}
0041 };
0042 MODULE_DEVICE_TABLE(x86cpu, soc_thermal_ids);
0043
0044 static int __init intel_soc_thermal_init(void)
0045 {
0046     int err = 0;
0047     const struct x86_cpu_id *match_cpu;
0048
0049     match_cpu = x86_match_cpu(soc_thermal_ids);
0050     if (!match_cpu)
0051         return -ENODEV;
0052
0053     /* Create a zone with 2 trips with marked as read only */
0054     soc_dts = intel_soc_dts_iosf_init(INTEL_SOC_DTS_INTERRUPT_APIC, 2, 1);
0055     if (IS_ERR(soc_dts)) {
0056         err = PTR_ERR(soc_dts);
0057         return err;
0058     }
0059
0060     soc_dts_thres_gsi = (int)match_cpu->driver_data;
0061     if (soc_dts_thres_gsi) {
0062         /*
0063          * Note the flags here MUST match the firmware defaults, rather
0064          * then the request_irq flags, otherwise we get an EBUSY error.
0065          */
0066         soc_dts_thres_irq = acpi_register_gsi(NULL, soc_dts_thres_gsi,
0067                               ACPI_LEVEL_SENSITIVE,
0068                               ACPI_ACTIVE_LOW);
0069         if (soc_dts_thres_irq < 0) {
0070             pr_warn("intel_soc_dts: Could not get IRQ for GSI %d, err %d\n",
0071                 soc_dts_thres_gsi, soc_dts_thres_irq);
0072             soc_dts_thres_irq = 0;
0073         }
0074     }
0075
0076     if (soc_dts_thres_irq) {
0077         err = request_threaded_irq(soc_dts_thres_irq, NULL,
0078                        soc_irq_thread_fn,
0079                        IRQF_TRIGGER_RISING | IRQF_ONESHOT,
0080                        "soc_dts", soc_dts);
0081         if (err) {
0082             /*
0083              * Do not just error out because the user space thermal
0084              * daemon such as DPTF may use polling instead of being
0085              * interrupt driven.
0086              */
0087             pr_warn("request_threaded_irq ret %d\n", err);
0088         }
0089     }
0090
0091     err = intel_soc_dts_iosf_add_read_only_critical_trip(soc_dts,
0092                                  crit_offset);
0093     if (err)
0094         goto error_trips;
0095
0096     return 0;
0097
0098 error_trips:
0099     if (soc_dts_thres_irq) {
0100         free_irq(soc_dts_thres_irq, soc_dts);
0101         acpi_unregister_gsi(soc_dts_thres_gsi);
0102     }
0103     intel_soc_dts_iosf_exit(soc_dts);
0104
0105     return err;
0106 }
0107
0108 static void __exit intel_soc_thermal_exit(void)
0109 {
0110     if (soc_dts_thres_irq) {
0111         free_irq(soc_dts_thres_irq, soc_dts);
0112         acpi_unregister_gsi(soc_dts_thres_gsi);
0113     }
0114     intel_soc_dts_iosf_exit(soc_dts);
0115 }
0116
0117 module_init(intel_soc_thermal_init)
0118 module_exit(intel_soc_thermal_exit)
0119
0120 MODULE_DESCRIPTION("Intel SoC DTS Thermal Driver");
0121 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
0122 MODULE_LICENSE("GPL v2");