cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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bcm2711_thermal.c (2860B)

      1// SPDX-License-Identifier: GPL-2.0+
      2/*
      3 * Broadcom AVS RO thermal sensor driver
      4 *
      5 * based on brcmstb_thermal
      6 *
      7 * Copyright (C) 2020 Stefan Wahren
      8 */
      9
     10#include <linux/bitops.h>
     11#include <linux/clk.h>
     12#include <linux/device.h>
     13#include <linux/err.h>
     14#include <linux/io.h>
     15#include <linux/kernel.h>
     16#include <linux/mfd/syscon.h>
     17#include <linux/module.h>
     18#include <linux/platform_device.h>
     19#include <linux/of_device.h>
     20#include <linux/regmap.h>
     21#include <linux/thermal.h>
     22
     23#include "../thermal_hwmon.h"
     24
     25#define AVS_RO_TEMP_STATUS		0x200
     26#define AVS_RO_TEMP_STATUS_VALID_MSK	(BIT(16) | BIT(10))
     27#define AVS_RO_TEMP_STATUS_DATA_MSK	GENMASK(9, 0)
     28
     29struct bcm2711_thermal_priv {
     30	struct regmap *regmap;
     31	struct thermal_zone_device *thermal;
     32};
     33
     34static int bcm2711_get_temp(void *data, int *temp)
     35{
     36	struct bcm2711_thermal_priv *priv = data;
     37	int slope = thermal_zone_get_slope(priv->thermal);
     38	int offset = thermal_zone_get_offset(priv->thermal);
     39	u32 val;
     40	int ret;
     41
     42	ret = regmap_read(priv->regmap, AVS_RO_TEMP_STATUS, &val);
     43	if (ret)
     44		return ret;
     45
     46	if (!(val & AVS_RO_TEMP_STATUS_VALID_MSK))
     47		return -EIO;
     48
     49	val &= AVS_RO_TEMP_STATUS_DATA_MSK;
     50
     51	/* Convert a HW code to a temperature reading (millidegree celsius) */
     52	*temp = slope * val + offset;
     53
     54	return 0;
     55}
     56
     57static const struct thermal_zone_of_device_ops bcm2711_thermal_of_ops = {
     58	.get_temp	= bcm2711_get_temp,
     59};
     60
     61static const struct of_device_id bcm2711_thermal_id_table[] = {
     62	{ .compatible = "brcm,bcm2711-thermal" },
     63	{},
     64};
     65MODULE_DEVICE_TABLE(of, bcm2711_thermal_id_table);
     66
     67static int bcm2711_thermal_probe(struct platform_device *pdev)
     68{
     69	struct thermal_zone_device *thermal;
     70	struct bcm2711_thermal_priv *priv;
     71	struct device *dev = &pdev->dev;
     72	struct device_node *parent;
     73	struct regmap *regmap;
     74	int ret;
     75
     76	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
     77	if (!priv)
     78		return -ENOMEM;
     79
     80	/* get regmap from syscon node */
     81	parent = of_get_parent(dev->of_node); /* parent should be syscon node */
     82	regmap = syscon_node_to_regmap(parent);
     83	of_node_put(parent);
     84	if (IS_ERR(regmap)) {
     85		ret = PTR_ERR(regmap);
     86		dev_err(dev, "failed to get regmap: %d\n", ret);
     87		return ret;
     88	}
     89	priv->regmap = regmap;
     90
     91	thermal = devm_thermal_zone_of_sensor_register(dev, 0, priv,
     92						       &bcm2711_thermal_of_ops);
     93	if (IS_ERR(thermal)) {
     94		ret = PTR_ERR(thermal);
     95		dev_err(dev, "could not register sensor: %d\n", ret);
     96		return ret;
     97	}
     98
     99	priv->thermal = thermal;
    100
    101	thermal->tzp->no_hwmon = false;
    102	return thermal_add_hwmon_sysfs(thermal);
    103}
    104
    105static struct platform_driver bcm2711_thermal_driver = {
    106	.probe = bcm2711_thermal_probe,
    107	.driver = {
    108		.name = "bcm2711_thermal",
    109		.of_match_table = bcm2711_thermal_id_table,
    110	},
    111};
    112module_platform_driver(bcm2711_thermal_driver);
    113
    114MODULE_LICENSE("GPL");
    115MODULE_AUTHOR("Stefan Wahren");
    116MODULE_DESCRIPTION("Broadcom AVS RO thermal sensor driver");