cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

kirkwood_thermal.c (3078B)

      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 * Kirkwood thermal sensor driver
      4 *
      5 * Copyright (C) 2012 Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
      6 */
      7#include <linux/device.h>
      8#include <linux/err.h>
      9#include <linux/io.h>
     10#include <linux/kernel.h>
     11#include <linux/of.h>
     12#include <linux/module.h>
     13#include <linux/platform_device.h>
     14#include <linux/thermal.h>
     15
     16#define KIRKWOOD_THERMAL_VALID_OFFSET	9
     17#define KIRKWOOD_THERMAL_VALID_MASK	0x1
     18#define KIRKWOOD_THERMAL_TEMP_OFFSET	10
     19#define KIRKWOOD_THERMAL_TEMP_MASK	0x1FF
     20
     21/* Kirkwood Thermal Sensor Dev Structure */
     22struct kirkwood_thermal_priv {
     23	void __iomem *sensor;
     24};
     25
     26static int kirkwood_get_temp(struct thermal_zone_device *thermal,
     27			  int *temp)
     28{
     29	unsigned long reg;
     30	struct kirkwood_thermal_priv *priv = thermal->devdata;
     31
     32	reg = readl_relaxed(priv->sensor);
     33
     34	/* Valid check */
     35	if (!((reg >> KIRKWOOD_THERMAL_VALID_OFFSET) &
     36	    KIRKWOOD_THERMAL_VALID_MASK)) {
     37		dev_err(&thermal->device,
     38			"Temperature sensor reading not valid\n");
     39		return -EIO;
     40	}
     41
     42	/*
     43	 * Calculate temperature. According to Marvell internal
     44	 * documentation the formula for this is:
     45	 * Celsius = (322-reg)/1.3625
     46	 */
     47	reg = (reg >> KIRKWOOD_THERMAL_TEMP_OFFSET) &
     48		KIRKWOOD_THERMAL_TEMP_MASK;
     49	*temp = ((3220000000UL - (10000000UL * reg)) / 13625);
     50
     51	return 0;
     52}
     53
     54static struct thermal_zone_device_ops ops = {
     55	.get_temp = kirkwood_get_temp,
     56};
     57
     58static const struct of_device_id kirkwood_thermal_id_table[] = {
     59	{ .compatible = "marvell,kirkwood-thermal" },
     60	{}
     61};
     62
     63static int kirkwood_thermal_probe(struct platform_device *pdev)
     64{
     65	struct thermal_zone_device *thermal = NULL;
     66	struct kirkwood_thermal_priv *priv;
     67	struct resource *res;
     68	int ret;
     69
     70	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
     71	if (!priv)
     72		return -ENOMEM;
     73
     74	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
     75	priv->sensor = devm_ioremap_resource(&pdev->dev, res);
     76	if (IS_ERR(priv->sensor))
     77		return PTR_ERR(priv->sensor);
     78
     79	thermal = thermal_zone_device_register("kirkwood_thermal", 0, 0,
     80					       priv, &ops, NULL, 0, 0);
     81	if (IS_ERR(thermal)) {
     82		dev_err(&pdev->dev,
     83			"Failed to register thermal zone device\n");
     84		return PTR_ERR(thermal);
     85	}
     86	ret = thermal_zone_device_enable(thermal);
     87	if (ret) {
     88		thermal_zone_device_unregister(thermal);
     89		dev_err(&pdev->dev, "Failed to enable thermal zone device\n");
     90		return ret;
     91	}
     92
     93	platform_set_drvdata(pdev, thermal);
     94
     95	return 0;
     96}
     97
     98static int kirkwood_thermal_exit(struct platform_device *pdev)
     99{
    100	struct thermal_zone_device *kirkwood_thermal =
    101		platform_get_drvdata(pdev);
    102
    103	thermal_zone_device_unregister(kirkwood_thermal);
    104
    105	return 0;
    106}
    107
    108MODULE_DEVICE_TABLE(of, kirkwood_thermal_id_table);
    109
    110static struct platform_driver kirkwood_thermal_driver = {
    111	.probe = kirkwood_thermal_probe,
    112	.remove = kirkwood_thermal_exit,
    113	.driver = {
    114		.name = "kirkwood_thermal",
    115		.of_match_table = kirkwood_thermal_id_table,
    116	},
    117};
    118
    119module_platform_driver(kirkwood_thermal_driver);
    120
    121MODULE_AUTHOR("Nobuhiro Iwamatsu <iwamatsu@nigauri.org>");
    122MODULE_DESCRIPTION("kirkwood thermal driver");
    123MODULE_LICENSE("GPL");