1/*
2 * intel_soc_dts_thermal.c
3 * Copyright (c) 2014, Intel Corporation.
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms and conditions of the GNU General Public License,
7 * version 2, as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 *
14 */
15
16#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
17
18#include <linux/acpi.h>
19#include <linux/module.h>
20#include <linux/interrupt.h>
21#include <asm/cpu_device_id.h>
22#include <asm/intel-family.h>
23#include "intel_soc_dts_iosf.h"
24
25#define CRITICAL_OFFSET_FROM_TJ_MAX 5000
26
27static int crit_offset = CRITICAL_OFFSET_FROM_TJ_MAX;
28module_param(crit_offset, int, 0644);
29MODULE_PARM_DESC(crit_offset,
30 "Critical Temperature offset from tj max in millidegree Celsius.");
31
32/* IRQ 86 is a fixed APIC interrupt for BYT DTS Aux threshold notifications */
33#define BYT_SOC_DTS_APIC_IRQ 86
34
35static int soc_dts_thres_gsi;
36static int soc_dts_thres_irq;
37static struct intel_soc_dts_sensors *soc_dts;
38
39static irqreturn_t soc_irq_thread_fn(int irq, void *dev_data)
40{
41 pr_debug("proc_thermal_interrupt\n");
42 intel_soc_dts_iosf_interrupt_handler(soc_dts);
43
44 return IRQ_HANDLED;
45}
46
47static const struct x86_cpu_id soc_thermal_ids[] = {
48 { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT, 0,
49 BYT_SOC_DTS_APIC_IRQ},
50 {}
51};
52MODULE_DEVICE_TABLE(x86cpu, soc_thermal_ids);
53
54static int __init intel_soc_thermal_init(void)
55{
56 int err = 0;
57 const struct x86_cpu_id *match_cpu;
58
59 match_cpu = x86_match_cpu(soc_thermal_ids);
60 if (!match_cpu)
61 return -ENODEV;
62
63 /* Create a zone with 2 trips with marked as read only */
64 soc_dts = intel_soc_dts_iosf_init(INTEL_SOC_DTS_INTERRUPT_APIC, 2, 1);
65 if (IS_ERR(soc_dts)) {
66 err = PTR_ERR(soc_dts);
67 return err;
68 }
69
70 soc_dts_thres_gsi = (int)match_cpu->driver_data;
71 if (soc_dts_thres_gsi) {
72 /*
73 * Note the flags here MUST match the firmware defaults, rather
74 * then the request_irq flags, otherwise we get an EBUSY error.
75 */
76 soc_dts_thres_irq = acpi_register_gsi(NULL, soc_dts_thres_gsi,
77 ACPI_LEVEL_SENSITIVE,
78 ACPI_ACTIVE_LOW);
79 if (soc_dts_thres_irq < 0) {
80 pr_warn("intel_soc_dts: Could not get IRQ for GSI %d, err %d\n",
81 soc_dts_thres_gsi, soc_dts_thres_irq);
82 soc_dts_thres_irq = 0;
83 }
84 }
85
86 if (soc_dts_thres_irq) {
87 err = request_threaded_irq(soc_dts_thres_irq, NULL,
88 soc_irq_thread_fn,
89 IRQF_TRIGGER_RISING | IRQF_ONESHOT,
90 "soc_dts", soc_dts);
91 if (err) {
92 /*
93 * Do not just error out because the user space thermal
94 * daemon such as DPTF may use polling instead of being
95 * interrupt driven.
96 */
97 pr_warn("request_threaded_irq ret %d\n", err);
98 }
99 }
100
101 err = intel_soc_dts_iosf_add_read_only_critical_trip(soc_dts,
102 crit_offset);
103 if (err)
104 goto error_trips;
105
106 return 0;
107
108error_trips:
109 if (soc_dts_thres_irq) {
110 free_irq(soc_dts_thres_irq, soc_dts);
111 acpi_unregister_gsi(soc_dts_thres_gsi);
112 }
113 intel_soc_dts_iosf_exit(soc_dts);
114
115 return err;
116}
117
118static void __exit intel_soc_thermal_exit(void)
119{
120 if (soc_dts_thres_irq) {
121 free_irq(soc_dts_thres_irq, soc_dts);
122 acpi_unregister_gsi(soc_dts_thres_gsi);
123 }
124 intel_soc_dts_iosf_exit(soc_dts);
125}
126
127module_init(intel_soc_thermal_init)
128module_exit(intel_soc_thermal_exit)
129
130MODULE_DESCRIPTION("Intel SoC DTS Thermal Driver");
131MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
132MODULE_LICENSE("GPL v2");
133