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
soc_irq_thread_fn(int irq,void * dev_data)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_INTEL_FAM6_MODEL(ATOM_SILVERMONT, BYT_SOC_DTS_APIC_IRQ),
40 {}
41 };
42 MODULE_DEVICE_TABLE(x86cpu, soc_thermal_ids);
43
intel_soc_thermal_init(void)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, 2, 1);
55 if (IS_ERR(soc_dts)) {
56 err = PTR_ERR(soc_dts);
57 return err;
58 }
59
60 soc_dts_thres_gsi = (int)match_cpu->driver_data;
61 if (soc_dts_thres_gsi) {
62 /*
63 * Note the flags here MUST match the firmware defaults, rather
64 * then the request_irq flags, otherwise we get an EBUSY error.
65 */
66 soc_dts_thres_irq = acpi_register_gsi(NULL, soc_dts_thres_gsi,
67 ACPI_LEVEL_SENSITIVE,
68 ACPI_ACTIVE_LOW);
69 if (soc_dts_thres_irq < 0) {
70 pr_warn("intel_soc_dts: Could not get IRQ for GSI %d, err %d\n",
71 soc_dts_thres_gsi, soc_dts_thres_irq);
72 soc_dts_thres_irq = 0;
73 }
74 }
75
76 if (soc_dts_thres_irq) {
77 err = request_threaded_irq(soc_dts_thres_irq, NULL,
78 soc_irq_thread_fn,
79 IRQF_TRIGGER_RISING | IRQF_ONESHOT,
80 "soc_dts", soc_dts);
81 if (err) {
82 /*
83 * Do not just error out because the user space thermal
84 * daemon such as DPTF may use polling instead of being
85 * interrupt driven.
86 */
87 pr_warn("request_threaded_irq ret %d\n", err);
88 }
89 }
90
91 err = intel_soc_dts_iosf_add_read_only_critical_trip(soc_dts,
92 crit_offset);
93 if (err)
94 goto error_trips;
95
96 return 0;
97
98 error_trips:
99 if (soc_dts_thres_irq) {
100 free_irq(soc_dts_thres_irq, soc_dts);
101 acpi_unregister_gsi(soc_dts_thres_gsi);
102 }
103 intel_soc_dts_iosf_exit(soc_dts);
104
105 return err;
106 }
107
intel_soc_thermal_exit(void)108 static void __exit intel_soc_thermal_exit(void)
109 {
110 if (soc_dts_thres_irq) {
111 free_irq(soc_dts_thres_irq, soc_dts);
112 acpi_unregister_gsi(soc_dts_thres_gsi);
113 }
114 intel_soc_dts_iosf_exit(soc_dts);
115 }
116
117 module_init(intel_soc_thermal_init)
118 module_exit(intel_soc_thermal_exit)
119
120 MODULE_DESCRIPTION("Intel SoC DTS Thermal Driver");
121 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
122 MODULE_LICENSE("GPL v2");
123