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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cputemp.c (13939B)


      1// SPDX-License-Identifier: GPL-2.0-only
      2// Copyright (c) 2018-2021 Intel Corporation
      3
      4#include <linux/auxiliary_bus.h>
      5#include <linux/bitfield.h>
      6#include <linux/bitops.h>
      7#include <linux/hwmon.h>
      8#include <linux/jiffies.h>
      9#include <linux/module.h>
     10#include <linux/peci.h>
     11#include <linux/peci-cpu.h>
     12#include <linux/units.h>
     13
     14#include "common.h"
     15
     16#define CORE_NUMS_MAX		64
     17
     18#define BASE_CHANNEL_NUMS	5
     19#define CPUTEMP_CHANNEL_NUMS	(BASE_CHANNEL_NUMS + CORE_NUMS_MAX)
     20
     21#define TEMP_TARGET_FAN_TEMP_MASK	GENMASK(15, 8)
     22#define TEMP_TARGET_REF_TEMP_MASK	GENMASK(23, 16)
     23#define TEMP_TARGET_TJ_OFFSET_MASK	GENMASK(29, 24)
     24
     25#define DTS_MARGIN_MASK		GENMASK(15, 0)
     26#define PCS_MODULE_TEMP_MASK	GENMASK(15, 0)
     27
     28struct resolved_cores_reg {
     29	u8 bus;
     30	u8 dev;
     31	u8 func;
     32	u8 offset;
     33};
     34
     35struct cpu_info {
     36	struct resolved_cores_reg *reg;
     37	u8 min_peci_revision;
     38	s32 (*thermal_margin_to_millidegree)(u16 val);
     39};
     40
     41struct peci_temp_target {
     42	s32 tcontrol;
     43	s32 tthrottle;
     44	s32 tjmax;
     45	struct peci_sensor_state state;
     46};
     47
     48enum peci_temp_target_type {
     49	tcontrol_type,
     50	tthrottle_type,
     51	tjmax_type,
     52	crit_hyst_type,
     53};
     54
     55struct peci_cputemp {
     56	struct peci_device *peci_dev;
     57	struct device *dev;
     58	const char *name;
     59	const struct cpu_info *gen_info;
     60	struct {
     61		struct peci_temp_target target;
     62		struct peci_sensor_data die;
     63		struct peci_sensor_data dts;
     64		struct peci_sensor_data core[CORE_NUMS_MAX];
     65	} temp;
     66	const char **coretemp_label;
     67	DECLARE_BITMAP(core_mask, CORE_NUMS_MAX);
     68};
     69
     70enum cputemp_channels {
     71	channel_die,
     72	channel_dts,
     73	channel_tcontrol,
     74	channel_tthrottle,
     75	channel_tjmax,
     76	channel_core,
     77};
     78
     79static const char * const cputemp_label[BASE_CHANNEL_NUMS] = {
     80	"Die",
     81	"DTS",
     82	"Tcontrol",
     83	"Tthrottle",
     84	"Tjmax",
     85};
     86
     87static int update_temp_target(struct peci_cputemp *priv)
     88{
     89	s32 tthrottle_offset, tcontrol_margin;
     90	u32 pcs;
     91	int ret;
     92
     93	if (!peci_sensor_need_update(&priv->temp.target.state))
     94		return 0;
     95
     96	ret = peci_pcs_read(priv->peci_dev, PECI_PCS_TEMP_TARGET, 0, &pcs);
     97	if (ret)
     98		return ret;
     99
    100	priv->temp.target.tjmax =
    101		FIELD_GET(TEMP_TARGET_REF_TEMP_MASK, pcs) * MILLIDEGREE_PER_DEGREE;
    102
    103	tcontrol_margin = FIELD_GET(TEMP_TARGET_FAN_TEMP_MASK, pcs);
    104	tcontrol_margin = sign_extend32(tcontrol_margin, 7) * MILLIDEGREE_PER_DEGREE;
    105	priv->temp.target.tcontrol = priv->temp.target.tjmax - tcontrol_margin;
    106
    107	tthrottle_offset = FIELD_GET(TEMP_TARGET_TJ_OFFSET_MASK, pcs) * MILLIDEGREE_PER_DEGREE;
    108	priv->temp.target.tthrottle = priv->temp.target.tjmax - tthrottle_offset;
    109
    110	peci_sensor_mark_updated(&priv->temp.target.state);
    111
    112	return 0;
    113}
    114
    115static int get_temp_target(struct peci_cputemp *priv, enum peci_temp_target_type type, long *val)
    116{
    117	int ret;
    118
    119	mutex_lock(&priv->temp.target.state.lock);
    120
    121	ret = update_temp_target(priv);
    122	if (ret)
    123		goto unlock;
    124
    125	switch (type) {
    126	case tcontrol_type:
    127		*val = priv->temp.target.tcontrol;
    128		break;
    129	case tthrottle_type:
    130		*val = priv->temp.target.tthrottle;
    131		break;
    132	case tjmax_type:
    133		*val = priv->temp.target.tjmax;
    134		break;
    135	case crit_hyst_type:
    136		*val = priv->temp.target.tjmax - priv->temp.target.tcontrol;
    137		break;
    138	default:
    139		ret = -EOPNOTSUPP;
    140		break;
    141	}
    142unlock:
    143	mutex_unlock(&priv->temp.target.state.lock);
    144
    145	return ret;
    146}
    147
    148/*
    149 * Error codes:
    150 *   0x8000: General sensor error
    151 *   0x8001: Reserved
    152 *   0x8002: Underflow on reading value
    153 *   0x8003-0x81ff: Reserved
    154 */
    155static bool dts_valid(u16 val)
    156{
    157	return val < 0x8000 || val > 0x81ff;
    158}
    159
    160/*
    161 * Processors return a value of DTS reading in S10.6 fixed point format
    162 * (16 bits: 10-bit signed magnitude, 6-bit fraction).
    163 */
    164static s32 dts_ten_dot_six_to_millidegree(u16 val)
    165{
    166	return sign_extend32(val, 15) * MILLIDEGREE_PER_DEGREE / 64;
    167}
    168
    169/*
    170 * For older processors, thermal margin reading is returned in S8.8 fixed
    171 * point format (16 bits: 8-bit signed magnitude, 8-bit fraction).
    172 */
    173static s32 dts_eight_dot_eight_to_millidegree(u16 val)
    174{
    175	return sign_extend32(val, 15) * MILLIDEGREE_PER_DEGREE / 256;
    176}
    177
    178static int get_die_temp(struct peci_cputemp *priv, long *val)
    179{
    180	int ret = 0;
    181	long tjmax;
    182	u16 temp;
    183
    184	mutex_lock(&priv->temp.die.state.lock);
    185	if (!peci_sensor_need_update(&priv->temp.die.state))
    186		goto skip_update;
    187
    188	ret = peci_temp_read(priv->peci_dev, &temp);
    189	if (ret)
    190		goto err_unlock;
    191
    192	if (!dts_valid(temp)) {
    193		ret = -EIO;
    194		goto err_unlock;
    195	}
    196
    197	ret = get_temp_target(priv, tjmax_type, &tjmax);
    198	if (ret)
    199		goto err_unlock;
    200
    201	priv->temp.die.value = (s32)tjmax + dts_ten_dot_six_to_millidegree(temp);
    202
    203	peci_sensor_mark_updated(&priv->temp.die.state);
    204
    205skip_update:
    206	*val = priv->temp.die.value;
    207err_unlock:
    208	mutex_unlock(&priv->temp.die.state.lock);
    209	return ret;
    210}
    211
    212static int get_dts(struct peci_cputemp *priv, long *val)
    213{
    214	int ret = 0;
    215	u16 thermal_margin;
    216	long tcontrol;
    217	u32 pcs;
    218
    219	mutex_lock(&priv->temp.dts.state.lock);
    220	if (!peci_sensor_need_update(&priv->temp.dts.state))
    221		goto skip_update;
    222
    223	ret = peci_pcs_read(priv->peci_dev, PECI_PCS_THERMAL_MARGIN, 0, &pcs);
    224	if (ret)
    225		goto err_unlock;
    226
    227	thermal_margin = FIELD_GET(DTS_MARGIN_MASK, pcs);
    228	if (!dts_valid(thermal_margin)) {
    229		ret = -EIO;
    230		goto err_unlock;
    231	}
    232
    233	ret = get_temp_target(priv, tcontrol_type, &tcontrol);
    234	if (ret)
    235		goto err_unlock;
    236
    237	/* Note that the tcontrol should be available before calling it */
    238	priv->temp.dts.value =
    239		(s32)tcontrol - priv->gen_info->thermal_margin_to_millidegree(thermal_margin);
    240
    241	peci_sensor_mark_updated(&priv->temp.dts.state);
    242
    243skip_update:
    244	*val = priv->temp.dts.value;
    245err_unlock:
    246	mutex_unlock(&priv->temp.dts.state.lock);
    247	return ret;
    248}
    249
    250static int get_core_temp(struct peci_cputemp *priv, int core_index, long *val)
    251{
    252	int ret = 0;
    253	u16 core_dts_margin;
    254	long tjmax;
    255	u32 pcs;
    256
    257	mutex_lock(&priv->temp.core[core_index].state.lock);
    258	if (!peci_sensor_need_update(&priv->temp.core[core_index].state))
    259		goto skip_update;
    260
    261	ret = peci_pcs_read(priv->peci_dev, PECI_PCS_MODULE_TEMP, core_index, &pcs);
    262	if (ret)
    263		goto err_unlock;
    264
    265	core_dts_margin = FIELD_GET(PCS_MODULE_TEMP_MASK, pcs);
    266	if (!dts_valid(core_dts_margin)) {
    267		ret = -EIO;
    268		goto err_unlock;
    269	}
    270
    271	ret = get_temp_target(priv, tjmax_type, &tjmax);
    272	if (ret)
    273		goto err_unlock;
    274
    275	/* Note that the tjmax should be available before calling it */
    276	priv->temp.core[core_index].value =
    277		(s32)tjmax + dts_ten_dot_six_to_millidegree(core_dts_margin);
    278
    279	peci_sensor_mark_updated(&priv->temp.core[core_index].state);
    280
    281skip_update:
    282	*val = priv->temp.core[core_index].value;
    283err_unlock:
    284	mutex_unlock(&priv->temp.core[core_index].state.lock);
    285	return ret;
    286}
    287
    288static int cputemp_read_string(struct device *dev, enum hwmon_sensor_types type,
    289			       u32 attr, int channel, const char **str)
    290{
    291	struct peci_cputemp *priv = dev_get_drvdata(dev);
    292
    293	if (attr != hwmon_temp_label)
    294		return -EOPNOTSUPP;
    295
    296	*str = channel < channel_core ?
    297		cputemp_label[channel] : priv->coretemp_label[channel - channel_core];
    298
    299	return 0;
    300}
    301
    302static int cputemp_read(struct device *dev, enum hwmon_sensor_types type,
    303			u32 attr, int channel, long *val)
    304{
    305	struct peci_cputemp *priv = dev_get_drvdata(dev);
    306
    307	switch (attr) {
    308	case hwmon_temp_input:
    309		switch (channel) {
    310		case channel_die:
    311			return get_die_temp(priv, val);
    312		case channel_dts:
    313			return get_dts(priv, val);
    314		case channel_tcontrol:
    315			return get_temp_target(priv, tcontrol_type, val);
    316		case channel_tthrottle:
    317			return get_temp_target(priv, tthrottle_type, val);
    318		case channel_tjmax:
    319			return get_temp_target(priv, tjmax_type, val);
    320		default:
    321			return get_core_temp(priv, channel - channel_core, val);
    322		}
    323		break;
    324	case hwmon_temp_max:
    325		return get_temp_target(priv, tcontrol_type, val);
    326	case hwmon_temp_crit:
    327		return get_temp_target(priv, tjmax_type, val);
    328	case hwmon_temp_crit_hyst:
    329		return get_temp_target(priv, crit_hyst_type, val);
    330	default:
    331		return -EOPNOTSUPP;
    332	}
    333
    334	return 0;
    335}
    336
    337static umode_t cputemp_is_visible(const void *data, enum hwmon_sensor_types type,
    338				  u32 attr, int channel)
    339{
    340	const struct peci_cputemp *priv = data;
    341
    342	if (channel > CPUTEMP_CHANNEL_NUMS)
    343		return 0;
    344
    345	if (channel < channel_core)
    346		return 0444;
    347
    348	if (test_bit(channel - channel_core, priv->core_mask))
    349		return 0444;
    350
    351	return 0;
    352}
    353
    354static int init_core_mask(struct peci_cputemp *priv)
    355{
    356	struct peci_device *peci_dev = priv->peci_dev;
    357	struct resolved_cores_reg *reg = priv->gen_info->reg;
    358	u64 core_mask;
    359	u32 data;
    360	int ret;
    361
    362	/* Get the RESOLVED_CORES register value */
    363	switch (peci_dev->info.model) {
    364	case INTEL_FAM6_ICELAKE_X:
    365	case INTEL_FAM6_ICELAKE_D:
    366		ret = peci_ep_pci_local_read(peci_dev, 0, reg->bus, reg->dev,
    367					     reg->func, reg->offset + 4, &data);
    368		if (ret)
    369			return ret;
    370
    371		core_mask = (u64)data << 32;
    372
    373		ret = peci_ep_pci_local_read(peci_dev, 0, reg->bus, reg->dev,
    374					     reg->func, reg->offset, &data);
    375		if (ret)
    376			return ret;
    377
    378		core_mask |= data;
    379
    380		break;
    381	default:
    382		ret = peci_pci_local_read(peci_dev, reg->bus, reg->dev,
    383					  reg->func, reg->offset, &data);
    384		if (ret)
    385			return ret;
    386
    387		core_mask = data;
    388
    389		break;
    390	}
    391
    392	if (!core_mask)
    393		return -EIO;
    394
    395	bitmap_from_u64(priv->core_mask, core_mask);
    396
    397	return 0;
    398}
    399
    400static int create_temp_label(struct peci_cputemp *priv)
    401{
    402	unsigned long core_max = find_last_bit(priv->core_mask, CORE_NUMS_MAX);
    403	int i;
    404
    405	priv->coretemp_label = devm_kzalloc(priv->dev, core_max * sizeof(char *), GFP_KERNEL);
    406	if (!priv->coretemp_label)
    407		return -ENOMEM;
    408
    409	for_each_set_bit(i, priv->core_mask, CORE_NUMS_MAX) {
    410		priv->coretemp_label[i] = devm_kasprintf(priv->dev, GFP_KERNEL, "Core %d", i);
    411		if (!priv->coretemp_label[i])
    412			return -ENOMEM;
    413	}
    414
    415	return 0;
    416}
    417
    418static void check_resolved_cores(struct peci_cputemp *priv)
    419{
    420	/*
    421	 * Failure to resolve cores is non-critical, we're still able to
    422	 * provide other sensor data.
    423	 */
    424
    425	if (init_core_mask(priv))
    426		return;
    427
    428	if (create_temp_label(priv))
    429		bitmap_zero(priv->core_mask, CORE_NUMS_MAX);
    430}
    431
    432static void sensor_init(struct peci_cputemp *priv)
    433{
    434	int i;
    435
    436	mutex_init(&priv->temp.target.state.lock);
    437	mutex_init(&priv->temp.die.state.lock);
    438	mutex_init(&priv->temp.dts.state.lock);
    439
    440	for_each_set_bit(i, priv->core_mask, CORE_NUMS_MAX)
    441		mutex_init(&priv->temp.core[i].state.lock);
    442}
    443
    444static const struct hwmon_ops peci_cputemp_ops = {
    445	.is_visible = cputemp_is_visible,
    446	.read_string = cputemp_read_string,
    447	.read = cputemp_read,
    448};
    449
    450static const struct hwmon_channel_info *peci_cputemp_info[] = {
    451	HWMON_CHANNEL_INFO(temp,
    452			   /* Die temperature */
    453			   HWMON_T_LABEL | HWMON_T_INPUT | HWMON_T_MAX |
    454			   HWMON_T_CRIT | HWMON_T_CRIT_HYST,
    455			   /* DTS margin */
    456			   HWMON_T_LABEL | HWMON_T_INPUT | HWMON_T_MAX |
    457			   HWMON_T_CRIT | HWMON_T_CRIT_HYST,
    458			   /* Tcontrol temperature */
    459			   HWMON_T_LABEL | HWMON_T_INPUT | HWMON_T_CRIT,
    460			   /* Tthrottle temperature */
    461			   HWMON_T_LABEL | HWMON_T_INPUT,
    462			   /* Tjmax temperature */
    463			   HWMON_T_LABEL | HWMON_T_INPUT,
    464			   /* Core temperature - for all core channels */
    465			   [channel_core ... CPUTEMP_CHANNEL_NUMS - 1] =
    466						HWMON_T_LABEL | HWMON_T_INPUT),
    467	NULL
    468};
    469
    470static const struct hwmon_chip_info peci_cputemp_chip_info = {
    471	.ops = &peci_cputemp_ops,
    472	.info = peci_cputemp_info,
    473};
    474
    475static int peci_cputemp_probe(struct auxiliary_device *adev,
    476			      const struct auxiliary_device_id *id)
    477{
    478	struct device *dev = &adev->dev;
    479	struct peci_device *peci_dev = to_peci_device(dev->parent);
    480	struct peci_cputemp *priv;
    481	struct device *hwmon_dev;
    482
    483	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
    484	if (!priv)
    485		return -ENOMEM;
    486
    487	priv->name = devm_kasprintf(dev, GFP_KERNEL, "peci_cputemp.cpu%d",
    488				    peci_dev->info.socket_id);
    489	if (!priv->name)
    490		return -ENOMEM;
    491
    492	priv->dev = dev;
    493	priv->peci_dev = peci_dev;
    494	priv->gen_info = (const struct cpu_info *)id->driver_data;
    495
    496	/*
    497	 * This is just a sanity check. Since we're using commands that are
    498	 * guaranteed to be supported on a given platform, we should never see
    499	 * revision lower than expected.
    500	 */
    501	if (peci_dev->info.peci_revision < priv->gen_info->min_peci_revision)
    502		dev_warn(priv->dev,
    503			 "Unexpected PECI revision %#x, some features may be unavailable\n",
    504			 peci_dev->info.peci_revision);
    505
    506	check_resolved_cores(priv);
    507
    508	sensor_init(priv);
    509
    510	hwmon_dev = devm_hwmon_device_register_with_info(priv->dev, priv->name,
    511							 priv, &peci_cputemp_chip_info, NULL);
    512
    513	return PTR_ERR_OR_ZERO(hwmon_dev);
    514}
    515
    516/*
    517 * RESOLVED_CORES PCI configuration register may have different location on
    518 * different platforms.
    519 */
    520static struct resolved_cores_reg resolved_cores_reg_hsx = {
    521	.bus = 1,
    522	.dev = 30,
    523	.func = 3,
    524	.offset = 0xb4,
    525};
    526
    527static struct resolved_cores_reg resolved_cores_reg_icx = {
    528	.bus = 14,
    529	.dev = 30,
    530	.func = 3,
    531	.offset = 0xd0,
    532};
    533
    534static const struct cpu_info cpu_hsx = {
    535	.reg		= &resolved_cores_reg_hsx,
    536	.min_peci_revision = 0x33,
    537	.thermal_margin_to_millidegree = &dts_eight_dot_eight_to_millidegree,
    538};
    539
    540static const struct cpu_info cpu_icx = {
    541	.reg		= &resolved_cores_reg_icx,
    542	.min_peci_revision = 0x40,
    543	.thermal_margin_to_millidegree = &dts_ten_dot_six_to_millidegree,
    544};
    545
    546static const struct auxiliary_device_id peci_cputemp_ids[] = {
    547	{
    548		.name = "peci_cpu.cputemp.hsx",
    549		.driver_data = (kernel_ulong_t)&cpu_hsx,
    550	},
    551	{
    552		.name = "peci_cpu.cputemp.bdx",
    553		.driver_data = (kernel_ulong_t)&cpu_hsx,
    554	},
    555	{
    556		.name = "peci_cpu.cputemp.bdxd",
    557		.driver_data = (kernel_ulong_t)&cpu_hsx,
    558	},
    559	{
    560		.name = "peci_cpu.cputemp.skx",
    561		.driver_data = (kernel_ulong_t)&cpu_hsx,
    562	},
    563	{
    564		.name = "peci_cpu.cputemp.icx",
    565		.driver_data = (kernel_ulong_t)&cpu_icx,
    566	},
    567	{
    568		.name = "peci_cpu.cputemp.icxd",
    569		.driver_data = (kernel_ulong_t)&cpu_icx,
    570	},
    571	{ }
    572};
    573MODULE_DEVICE_TABLE(auxiliary, peci_cputemp_ids);
    574
    575static struct auxiliary_driver peci_cputemp_driver = {
    576	.probe		= peci_cputemp_probe,
    577	.id_table	= peci_cputemp_ids,
    578};
    579
    580module_auxiliary_driver(peci_cputemp_driver);
    581
    582MODULE_AUTHOR("Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>");
    583MODULE_AUTHOR("Iwona Winiarska <iwona.winiarska@intel.com>");
    584MODULE_DESCRIPTION("PECI cputemp driver");
    585MODULE_LICENSE("GPL");
    586MODULE_IMPORT_NS(PECI_CPU);