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1// SPDX-License-Identifier: GPL-2.02/*3 * Intel Platform Monitory Technology Telemetry driver4 *5 * Copyright (c) 2020, Intel Corporation.6 * All Rights Reserved.7 *8 * Author: "David E. Box" <david.e.box@linux.intel.com>9 */10 11#include <linux/auxiliary_bus.h>12#include <linux/intel_vsec.h>13#include <linux/kernel.h>14#include <linux/module.h>15#include <linux/pci.h>16#include <linux/slab.h>17#include <linux/uaccess.h>18#include <linux/overflow.h>19 20#include "class.h"21 22#define TELEM_SIZE_OFFSET 0x023#define TELEM_GUID_OFFSET 0x424#define TELEM_BASE_OFFSET 0x825#define TELEM_ACCESS(v) ((v) & GENMASK(3, 0))26#define TELEM_TYPE(v) (((v) & GENMASK(7, 4)) >> 4)27/* size is in bytes */28#define TELEM_SIZE(v) (((v) & GENMASK(27, 12)) >> 10)29 30/* Used by client hardware to identify a fixed telemetry entry*/31#define TELEM_CLIENT_FIXED_BLOCK_GUID 0x1000000032 33#define NUM_BYTES_QWORD(v) ((v) << 3)34#define SAMPLE_ID_OFFSET(v) ((v) << 3)35 36#define NUM_BYTES_DWORD(v) ((v) << 2)37#define SAMPLE_ID_OFFSET32(v) ((v) << 2)38 39/* Protects access to the xarray of telemetry endpoint handles */40static DEFINE_MUTEX(ep_lock);41 42enum telem_type {43 TELEM_TYPE_PUNIT = 0,44 TELEM_TYPE_CRASHLOG,45 TELEM_TYPE_PUNIT_FIXED,46};47 48struct pmt_telem_priv {49 int num_entries;50 struct intel_pmt_entry entry[];51};52 53static bool pmt_telem_region_overlaps(struct intel_pmt_entry *entry,54 struct device *dev)55{56 u32 guid = readl(entry->disc_table + TELEM_GUID_OFFSET);57 58 if (intel_pmt_is_early_client_hw(dev)) {59 u32 type = TELEM_TYPE(readl(entry->disc_table));60 61 if ((type == TELEM_TYPE_PUNIT_FIXED) ||62 (guid == TELEM_CLIENT_FIXED_BLOCK_GUID))63 return true;64 }65 66 return false;67}68 69static int pmt_telem_header_decode(struct intel_pmt_entry *entry,70 struct device *dev)71{72 void __iomem *disc_table = entry->disc_table;73 struct intel_pmt_header *header = &entry->header;74 75 if (pmt_telem_region_overlaps(entry, dev))76 return 1;77 78 header->access_type = TELEM_ACCESS(readl(disc_table));79 header->guid = readl(disc_table + TELEM_GUID_OFFSET);80 header->base_offset = readl(disc_table + TELEM_BASE_OFFSET);81 82 /* Size is measured in DWORDS, but accessor returns bytes */83 header->size = TELEM_SIZE(readl(disc_table));84 85 /*86 * Some devices may expose non-functioning entries that are87 * reserved for future use. They have zero size. Do not fail88 * probe for these. Just ignore them.89 */90 if (header->size == 0 || header->access_type == 0xF)91 return 1;92 93 return 0;94}95 96static int pmt_telem_add_endpoint(struct intel_vsec_device *ivdev,97 struct intel_pmt_entry *entry)98{99 struct telem_endpoint *ep;100 101 /* Endpoint lifetimes are managed by kref, not devres */102 entry->ep = kzalloc(sizeof(*(entry->ep)), GFP_KERNEL);103 if (!entry->ep)104 return -ENOMEM;105 106 ep = entry->ep;107 ep->pcidev = ivdev->pcidev;108 ep->header.access_type = entry->header.access_type;109 ep->header.guid = entry->header.guid;110 ep->header.base_offset = entry->header.base_offset;111 ep->header.size = entry->header.size;112 ep->base = entry->base;113 ep->present = true;114 ep->cb = ivdev->priv_data;115 116 kref_init(&ep->kref);117 118 return 0;119}120 121static DEFINE_XARRAY_ALLOC(telem_array);122static struct intel_pmt_namespace pmt_telem_ns = {123 .name = "telem",124 .xa = &telem_array,125 .pmt_header_decode = pmt_telem_header_decode,126 .pmt_add_endpoint = pmt_telem_add_endpoint,127};128 129/* Called when all users unregister and the device is removed */130static void pmt_telem_ep_release(struct kref *kref)131{132 struct telem_endpoint *ep;133 134 ep = container_of(kref, struct telem_endpoint, kref);135 kfree(ep);136}137 138unsigned long pmt_telem_get_next_endpoint(unsigned long start)139{140 struct intel_pmt_entry *entry;141 unsigned long found_idx;142 143 mutex_lock(&ep_lock);144 xa_for_each_start(&telem_array, found_idx, entry, start) {145 /*146 * Return first found index after start.147 * 0 is not valid id.148 */149 if (found_idx > start)150 break;151 }152 mutex_unlock(&ep_lock);153 154 return found_idx == start ? 0 : found_idx;155}156EXPORT_SYMBOL_NS_GPL(pmt_telem_get_next_endpoint, INTEL_PMT_TELEMETRY);157 158struct telem_endpoint *pmt_telem_register_endpoint(int devid)159{160 struct intel_pmt_entry *entry;161 unsigned long index = devid;162 163 mutex_lock(&ep_lock);164 entry = xa_find(&telem_array, &index, index, XA_PRESENT);165 if (!entry) {166 mutex_unlock(&ep_lock);167 return ERR_PTR(-ENXIO);168 }169 170 kref_get(&entry->ep->kref);171 mutex_unlock(&ep_lock);172 173 return entry->ep;174}175EXPORT_SYMBOL_NS_GPL(pmt_telem_register_endpoint, INTEL_PMT_TELEMETRY);176 177void pmt_telem_unregister_endpoint(struct telem_endpoint *ep)178{179 kref_put(&ep->kref, pmt_telem_ep_release);180}181EXPORT_SYMBOL_NS_GPL(pmt_telem_unregister_endpoint, INTEL_PMT_TELEMETRY);182 183int pmt_telem_get_endpoint_info(int devid, struct telem_endpoint_info *info)184{185 struct intel_pmt_entry *entry;186 unsigned long index = devid;187 int err = 0;188 189 if (!info)190 return -EINVAL;191 192 mutex_lock(&ep_lock);193 entry = xa_find(&telem_array, &index, index, XA_PRESENT);194 if (!entry) {195 err = -ENXIO;196 goto unlock;197 }198 199 info->pdev = entry->ep->pcidev;200 info->header = entry->ep->header;201 202unlock:203 mutex_unlock(&ep_lock);204 return err;205 206}207EXPORT_SYMBOL_NS_GPL(pmt_telem_get_endpoint_info, INTEL_PMT_TELEMETRY);208 209int pmt_telem_read(struct telem_endpoint *ep, u32 id, u64 *data, u32 count)210{211 u32 offset, size;212 213 if (!ep->present)214 return -ENODEV;215 216 offset = SAMPLE_ID_OFFSET(id);217 size = ep->header.size;218 219 if (offset + NUM_BYTES_QWORD(count) > size)220 return -EINVAL;221 222 pmt_telem_read_mmio(ep->pcidev, ep->cb, ep->header.guid, data, ep->base + offset,223 NUM_BYTES_QWORD(count));224 225 return ep->present ? 0 : -EPIPE;226}227EXPORT_SYMBOL_NS_GPL(pmt_telem_read, INTEL_PMT_TELEMETRY);228 229int pmt_telem_read32(struct telem_endpoint *ep, u32 id, u32 *data, u32 count)230{231 u32 offset, size;232 233 if (!ep->present)234 return -ENODEV;235 236 offset = SAMPLE_ID_OFFSET32(id);237 size = ep->header.size;238 239 if (offset + NUM_BYTES_DWORD(count) > size)240 return -EINVAL;241 242 memcpy_fromio(data, ep->base + offset, NUM_BYTES_DWORD(count));243 244 return ep->present ? 0 : -EPIPE;245}246EXPORT_SYMBOL_NS_GPL(pmt_telem_read32, INTEL_PMT_TELEMETRY);247 248struct telem_endpoint *249pmt_telem_find_and_register_endpoint(struct pci_dev *pcidev, u32 guid, u16 pos)250{251 int devid = 0;252 int inst = 0;253 int err = 0;254 255 while ((devid = pmt_telem_get_next_endpoint(devid))) {256 struct telem_endpoint_info ep_info;257 258 err = pmt_telem_get_endpoint_info(devid, &ep_info);259 if (err)260 return ERR_PTR(err);261 262 if (ep_info.header.guid == guid && ep_info.pdev == pcidev) {263 if (inst == pos)264 return pmt_telem_register_endpoint(devid);265 ++inst;266 }267 }268 269 return ERR_PTR(-ENXIO);270}271EXPORT_SYMBOL_NS_GPL(pmt_telem_find_and_register_endpoint, INTEL_PMT_TELEMETRY);272 273static void pmt_telem_remove(struct auxiliary_device *auxdev)274{275 struct pmt_telem_priv *priv = auxiliary_get_drvdata(auxdev);276 int i;277 278 mutex_lock(&ep_lock);279 for (i = 0; i < priv->num_entries; i++) {280 struct intel_pmt_entry *entry = &priv->entry[i];281 282 kref_put(&entry->ep->kref, pmt_telem_ep_release);283 intel_pmt_dev_destroy(entry, &pmt_telem_ns);284 }285 mutex_unlock(&ep_lock);286};287 288static int pmt_telem_probe(struct auxiliary_device *auxdev, const struct auxiliary_device_id *id)289{290 struct intel_vsec_device *intel_vsec_dev = auxdev_to_ivdev(auxdev);291 struct pmt_telem_priv *priv;292 size_t size;293 int i, ret;294 295 size = struct_size(priv, entry, intel_vsec_dev->num_resources);296 priv = devm_kzalloc(&auxdev->dev, size, GFP_KERNEL);297 if (!priv)298 return -ENOMEM;299 300 auxiliary_set_drvdata(auxdev, priv);301 302 for (i = 0; i < intel_vsec_dev->num_resources; i++) {303 struct intel_pmt_entry *entry = &priv->entry[priv->num_entries];304 305 mutex_lock(&ep_lock);306 ret = intel_pmt_dev_create(entry, &pmt_telem_ns, intel_vsec_dev, i);307 mutex_unlock(&ep_lock);308 if (ret < 0)309 goto abort_probe;310 if (ret)311 continue;312 313 priv->num_entries++;314 }315 316 return 0;317abort_probe:318 pmt_telem_remove(auxdev);319 return ret;320}321 322static const struct auxiliary_device_id pmt_telem_id_table[] = {323 { .name = "intel_vsec.telemetry" },324 {}325};326MODULE_DEVICE_TABLE(auxiliary, pmt_telem_id_table);327 328static struct auxiliary_driver pmt_telem_aux_driver = {329 .id_table = pmt_telem_id_table,330 .remove = pmt_telem_remove,331 .probe = pmt_telem_probe,332};333 334static int __init pmt_telem_init(void)335{336 return auxiliary_driver_register(&pmt_telem_aux_driver);337}338module_init(pmt_telem_init);339 340static void __exit pmt_telem_exit(void)341{342 auxiliary_driver_unregister(&pmt_telem_aux_driver);343 xa_destroy(&telem_array);344}345module_exit(pmt_telem_exit);346 347MODULE_AUTHOR("David E. Box <david.e.box@linux.intel.com>");348MODULE_DESCRIPTION("Intel PMT Telemetry driver");349MODULE_LICENSE("GPL v2");350MODULE_IMPORT_NS(INTEL_PMT);351