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
 18static int crit_offset = CRITICAL_OFFSET_FROM_TJ_MAX;
 19module_param(crit_offset, int, 0644);
 20MODULE_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
 26static int soc_dts_thres_gsi;
 27static int soc_dts_thres_irq;
 28static struct intel_soc_dts_sensors *soc_dts;
 29
 30static 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
 38static const struct x86_cpu_id soc_thermal_ids[] = {
 39	X86_MATCH_INTEL_FAM6_MODEL(ATOM_SILVERMONT, BYT_SOC_DTS_APIC_IRQ),
 40	{}
 41};
 42MODULE_DEVICE_TABLE(x86cpu, soc_thermal_ids);
 43
 44static 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
 98error_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
108static 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
117module_init(intel_soc_thermal_init)
118module_exit(intel_soc_thermal_exit)
119
120MODULE_DESCRIPTION("Intel SoC DTS Thermal Driver");
121MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
122MODULE_LICENSE("GPL v2");