drivers/thermal/intel/intel_soc_dts_thermal.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * intel_soc_dts_thermal.c
   4  * Copyright (c) 2014, Intel Corporation.
   5  */
   6
   7 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   8
   9 #include <linux/acpi.h>
  10 #include <linux/module.h>
  11 #include <linux/interrupt.h>
  12 #include <asm/cpu_device_id.h>
  13 #include <asm/intel-family.h>
  14 #include "intel_soc_dts_iosf.h"
  15
  16 #define CRITICAL_OFFSET_FROM_TJ_MAX     5000
  17
  18 static int crit_offset = CRITICAL_OFFSET_FROM_TJ_MAX;
  19 module_param(crit_offset, int, 0644);
  20 MODULE_PARM_DESC(crit_offset,
  21         "Critical Temperature offset from tj max in millidegree Celsius.");
  22
  23 /* IRQ 86 is a fixed APIC interrupt for BYT DTS Aux threshold notifications */
  24 #define BYT_SOC_DTS_APIC_IRQ    86
  25
  26 static int soc_dts_thres_gsi;
  27 static int soc_dts_thres_irq;
  28 static struct intel_soc_dts_sensors *soc_dts;
  29
  30 static irqreturn_t soc_irq_thread_fn(int irq, void *dev_data)
  31 {
  32         pr_debug("proc_thermal_interrupt\n");
  33         intel_soc_dts_iosf_interrupt_handler(soc_dts);
  34
  35         return IRQ_HANDLED;
  36 }
  37
  38 static const struct x86_cpu_id soc_thermal_ids[] = {
  39         X86_MATCH_VFM(INTEL_ATOM_SILVERMONT, BYT_SOC_DTS_APIC_IRQ),
  40         {}
  41 };
  42 MODULE_DEVICE_TABLE(x86cpu, soc_thermal_ids);
  43
  44 static int __init intel_soc_thermal_init(void)
  45 {
  46         int err = 0;
  47         const struct x86_cpu_id *match_cpu;
  48
  49         match_cpu = x86_match_cpu(soc_thermal_ids);
  50         if (!match_cpu)
  51                 return -ENODEV;
  52
  53         /* Create a zone with 2 trips with marked as read only */
  54         soc_dts = intel_soc_dts_iosf_init(INTEL_SOC_DTS_INTERRUPT_APIC, true,
  55                                           crit_offset);
  56         if (IS_ERR(soc_dts)) {
  57                 err = PTR_ERR(soc_dts);
  58                 return err;
  59         }
  60
  61         soc_dts_thres_gsi = (int)match_cpu->driver_data;
  62         if (soc_dts_thres_gsi) {
  63                 /*
  64                  * Note the flags here MUST match the firmware defaults, rather
  65                  * then the request_irq flags, otherwise we get an EBUSY error.
  66                  */
  67                 soc_dts_thres_irq = acpi_register_gsi(NULL, soc_dts_thres_gsi,
  68                                                       ACPI_LEVEL_SENSITIVE,
  69                                                       ACPI_ACTIVE_LOW);
  70                 if (soc_dts_thres_irq < 0) {
  71                         pr_warn("intel_soc_dts: Could not get IRQ for GSI %d, err %d\n",
  72                                 soc_dts_thres_gsi, soc_dts_thres_irq);
  73                         soc_dts_thres_irq = 0;
  74                 }
  75         }
  76
  77         if (soc_dts_thres_irq) {
  78                 err = request_threaded_irq(soc_dts_thres_irq, NULL,
  79                                            soc_irq_thread_fn,
  80                                            IRQF_TRIGGER_RISING | IRQF_ONESHOT,
  81                                            "soc_dts", soc_dts);
  82                 if (err) {
  83                         /*
  84                          * Do not just error out because the user space thermal
  85                          * daemon such as DPTF may use polling instead of being
  86                          * interrupt driven.
  87                          */
  88                         pr_warn("request_threaded_irq ret %d\n", err);
  89                 }
  90         }
  91
  92         return 0;
  93 }
  94
  95 static void __exit intel_soc_thermal_exit(void)
  96 {
  97         if (soc_dts_thres_irq) {
  98                 free_irq(soc_dts_thres_irq, soc_dts);
  99                 acpi_unregister_gsi(soc_dts_thres_gsi);
 100         }
 101         intel_soc_dts_iosf_exit(soc_dts);
 102 }
 103
 104 module_init(intel_soc_thermal_init)
 105 module_exit(intel_soc_thermal_exit)
 106
 107 MODULE_DESCRIPTION("Intel SoC DTS Thermal Driver");
 108 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
 109 MODULE_LICENSE("GPL v2");