1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Intel Platform Monitory Technology Telemetry driver 4 * 5 * Copyright (c) 2020, Intel Corporation. 6 * All Rights Reserved. 7 * 8 * Author: "Alexander Duyck" <alexander.h.duyck@linux.intel.com> 9 */ 10 11 #include <linux/kernel.h> 12 #include <linux/intel_vsec.h> 13 #include <linux/io-64-nonatomic-lo-hi.h> 14 #include <linux/module.h> 15 #include <linux/mm.h> 16 #include <linux/pci.h> 17 18 #include "class.h" 19 20 #define PMT_XA_START 1 21 #define PMT_XA_MAX INT_MAX 22 #define PMT_XA_LIMIT XA_LIMIT(PMT_XA_START, PMT_XA_MAX) 23 #define GUID_SPR_PUNIT 0x9956f43f 24 25 bool intel_pmt_is_early_client_hw(struct device *dev) 26 { 27 struct intel_vsec_device *ivdev = dev_to_ivdev(dev); 28 29 /* 30 * Early implementations of PMT on client platforms have some 31 * differences from the server platforms (which use the Out Of Band 32 * Management Services Module OOBMSM). 33 */ 34 return !!(ivdev->quirks & VSEC_QUIRK_EARLY_HW); 35 } 36 EXPORT_SYMBOL_NS_GPL(intel_pmt_is_early_client_hw, INTEL_PMT); 37 38 static inline int 39 pmt_memcpy64_fromio(void *to, const u64 __iomem *from, size_t count) 40 { 41 int i, remain; 42 u64 *buf = to; 43 44 if (!IS_ALIGNED((unsigned long)from, 8)) 45 return -EFAULT; 46 47 for (i = 0; i < count/8; i++) 48 buf[i] = readq(&from[i]); 49 50 /* Copy any remaining bytes */ 51 remain = count % 8; 52 if (remain) { 53 u64 tmp = readq(&from[i]); 54 55 memcpy(&buf[i], &tmp, remain); 56 } 57 58 return count; 59 } 60 61 int pmt_telem_read_mmio(struct pci_dev *pdev, struct pmt_callbacks *cb, u32 guid, void *buf, 62 void __iomem *addr, u32 count) 63 { 64 if (cb && cb->read_telem) 65 return cb->read_telem(pdev, guid, buf, count); 66 67 if (guid == GUID_SPR_PUNIT) 68 /* PUNIT on SPR only supports aligned 64-bit read */ 69 return pmt_memcpy64_fromio(buf, addr, count); 70 71 memcpy_fromio(buf, addr, count); 72 73 return count; 74 } 75 EXPORT_SYMBOL_NS_GPL(pmt_telem_read_mmio, INTEL_PMT); 76 77 /* 78 * sysfs 79 */ 80 static ssize_t 81 intel_pmt_read(struct file *filp, struct kobject *kobj, 82 struct bin_attribute *attr, char *buf, loff_t off, 83 size_t count) 84 { 85 struct intel_pmt_entry *entry = container_of(attr, 86 struct intel_pmt_entry, 87 pmt_bin_attr); 88 89 if (off < 0) 90 return -EINVAL; 91 92 if (off >= entry->size) 93 return 0; 94 95 if (count > entry->size - off) 96 count = entry->size - off; 97 98 count = pmt_telem_read_mmio(entry->ep->pcidev, entry->cb, entry->header.guid, buf, 99 entry->base + off, count); 100 101 return count; 102 } 103 104 static int 105 intel_pmt_mmap(struct file *filp, struct kobject *kobj, 106 struct bin_attribute *attr, struct vm_area_struct *vma) 107 { 108 struct intel_pmt_entry *entry = container_of(attr, 109 struct intel_pmt_entry, 110 pmt_bin_attr); 111 unsigned long vsize = vma->vm_end - vma->vm_start; 112 struct device *dev = kobj_to_dev(kobj); 113 unsigned long phys = entry->base_addr; 114 unsigned long pfn = PFN_DOWN(phys); 115 unsigned long psize; 116 117 if (vma->vm_flags & (VM_WRITE | VM_MAYWRITE)) 118 return -EROFS; 119 120 psize = (PFN_UP(entry->base_addr + entry->size) - pfn) * PAGE_SIZE; 121 if (vsize > psize) { 122 dev_err(dev, "Requested mmap size is too large\n"); 123 return -EINVAL; 124 } 125 126 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); 127 if (io_remap_pfn_range(vma, vma->vm_start, pfn, 128 vsize, vma->vm_page_prot)) 129 return -EAGAIN; 130 131 return 0; 132 } 133 134 static ssize_t 135 guid_show(struct device *dev, struct device_attribute *attr, char *buf) 136 { 137 struct intel_pmt_entry *entry = dev_get_drvdata(dev); 138 139 return sprintf(buf, "0x%x\n", entry->guid); 140 } 141 static DEVICE_ATTR_RO(guid); 142 143 static ssize_t size_show(struct device *dev, struct device_attribute *attr, 144 char *buf) 145 { 146 struct intel_pmt_entry *entry = dev_get_drvdata(dev); 147 148 return sprintf(buf, "%zu\n", entry->size); 149 } 150 static DEVICE_ATTR_RO(size); 151 152 static ssize_t 153 offset_show(struct device *dev, struct device_attribute *attr, char *buf) 154 { 155 struct intel_pmt_entry *entry = dev_get_drvdata(dev); 156 157 return sprintf(buf, "%lu\n", offset_in_page(entry->base_addr)); 158 } 159 static DEVICE_ATTR_RO(offset); 160 161 static struct attribute *intel_pmt_attrs[] = { 162 &dev_attr_guid.attr, 163 &dev_attr_size.attr, 164 &dev_attr_offset.attr, 165 NULL 166 }; 167 ATTRIBUTE_GROUPS(intel_pmt); 168 169 static struct class intel_pmt_class = { 170 .name = "intel_pmt", 171 .dev_groups = intel_pmt_groups, 172 }; 173 174 static int intel_pmt_populate_entry(struct intel_pmt_entry *entry, 175 struct intel_vsec_device *ivdev, 176 struct resource *disc_res) 177 { 178 struct pci_dev *pci_dev = ivdev->pcidev; 179 struct device *dev = &ivdev->auxdev.dev; 180 struct intel_pmt_header *header = &entry->header; 181 u8 bir; 182 183 /* 184 * The base offset should always be 8 byte aligned. 185 * 186 * For non-local access types the lower 3 bits of base offset 187 * contains the index of the base address register where the 188 * telemetry can be found. 189 */ 190 bir = GET_BIR(header->base_offset); 191 192 /* Local access and BARID only for now */ 193 switch (header->access_type) { 194 case ACCESS_LOCAL: 195 if (bir) { 196 dev_err(dev, 197 "Unsupported BAR index %d for access type %d\n", 198 bir, header->access_type); 199 return -EINVAL; 200 } 201 /* 202 * For access_type LOCAL, the base address is as follows: 203 * base address = end of discovery region + base offset 204 */ 205 entry->base_addr = disc_res->end + 1 + header->base_offset; 206 207 /* 208 * Some hardware use a different calculation for the base address 209 * when access_type == ACCESS_LOCAL. On the these systems 210 * ACCCESS_LOCAL refers to an address in the same BAR as the 211 * header but at a fixed offset. But as the header address was 212 * supplied to the driver, we don't know which BAR it was in. 213 * So search for the bar whose range includes the header address. 214 */ 215 if (intel_pmt_is_early_client_hw(dev)) { 216 int i; 217 218 entry->base_addr = 0; 219 for (i = 0; i < 6; i++) 220 if (disc_res->start >= pci_resource_start(pci_dev, i) && 221 (disc_res->start <= pci_resource_end(pci_dev, i))) { 222 entry->base_addr = pci_resource_start(pci_dev, i) + 223 header->base_offset; 224 break; 225 } 226 if (!entry->base_addr) 227 return -EINVAL; 228 } 229 230 break; 231 case ACCESS_BARID: 232 /* Use the provided base address if it exists */ 233 if (ivdev->base_addr) { 234 entry->base_addr = ivdev->base_addr + 235 GET_ADDRESS(header->base_offset); 236 break; 237 } 238 239 /* 240 * If another BAR was specified then the base offset 241 * represents the offset within that BAR. SO retrieve the 242 * address from the parent PCI device and add offset. 243 */ 244 entry->base_addr = pci_resource_start(pci_dev, bir) + 245 GET_ADDRESS(header->base_offset); 246 break; 247 default: 248 dev_err(dev, "Unsupported access type %d\n", 249 header->access_type); 250 return -EINVAL; 251 } 252 253 entry->guid = header->guid; 254 entry->size = header->size; 255 entry->cb = ivdev->priv_data; 256 257 return 0; 258 } 259 260 static int intel_pmt_dev_register(struct intel_pmt_entry *entry, 261 struct intel_pmt_namespace *ns, 262 struct device *parent) 263 { 264 struct intel_vsec_device *ivdev = dev_to_ivdev(parent); 265 struct resource res = {0}; 266 struct device *dev; 267 int ret; 268 269 ret = xa_alloc(ns->xa, &entry->devid, entry, PMT_XA_LIMIT, GFP_KERNEL); 270 if (ret) 271 return ret; 272 273 dev = device_create(&intel_pmt_class, parent, MKDEV(0, 0), entry, 274 "%s%d", ns->name, entry->devid); 275 276 if (IS_ERR(dev)) { 277 dev_err(parent, "Could not create %s%d device node\n", 278 ns->name, entry->devid); 279 ret = PTR_ERR(dev); 280 goto fail_dev_create; 281 } 282 283 entry->kobj = &dev->kobj; 284 285 if (ns->attr_grp) { 286 ret = sysfs_create_group(entry->kobj, ns->attr_grp); 287 if (ret) 288 goto fail_sysfs_create_group; 289 } 290 291 /* if size is 0 assume no data buffer, so no file needed */ 292 if (!entry->size) 293 return 0; 294 295 res.start = entry->base_addr; 296 res.end = res.start + entry->size - 1; 297 res.flags = IORESOURCE_MEM; 298 299 entry->base = devm_ioremap_resource(dev, &res); 300 if (IS_ERR(entry->base)) { 301 ret = PTR_ERR(entry->base); 302 goto fail_ioremap; 303 } 304 305 sysfs_bin_attr_init(&entry->pmt_bin_attr); 306 entry->pmt_bin_attr.attr.name = ns->name; 307 entry->pmt_bin_attr.attr.mode = 0440; 308 entry->pmt_bin_attr.mmap = intel_pmt_mmap; 309 entry->pmt_bin_attr.read = intel_pmt_read; 310 entry->pmt_bin_attr.size = entry->size; 311 312 ret = sysfs_create_bin_file(&dev->kobj, &entry->pmt_bin_attr); 313 if (ret) 314 goto fail_ioremap; 315 316 if (ns->pmt_add_endpoint) { 317 ret = ns->pmt_add_endpoint(ivdev, entry); 318 if (ret) 319 goto fail_add_endpoint; 320 } 321 322 return 0; 323 324 fail_add_endpoint: 325 sysfs_remove_bin_file(entry->kobj, &entry->pmt_bin_attr); 326 fail_ioremap: 327 if (ns->attr_grp) 328 sysfs_remove_group(entry->kobj, ns->attr_grp); 329 fail_sysfs_create_group: 330 device_unregister(dev); 331 fail_dev_create: 332 xa_erase(ns->xa, entry->devid); 333 334 return ret; 335 } 336 337 int intel_pmt_dev_create(struct intel_pmt_entry *entry, struct intel_pmt_namespace *ns, 338 struct intel_vsec_device *intel_vsec_dev, int idx) 339 { 340 struct device *dev = &intel_vsec_dev->auxdev.dev; 341 struct resource *disc_res; 342 int ret; 343 344 disc_res = &intel_vsec_dev->resource[idx]; 345 346 entry->disc_table = devm_ioremap_resource(dev, disc_res); 347 if (IS_ERR(entry->disc_table)) 348 return PTR_ERR(entry->disc_table); 349 350 ret = ns->pmt_header_decode(entry, dev); 351 if (ret) 352 return ret; 353 354 ret = intel_pmt_populate_entry(entry, intel_vsec_dev, disc_res); 355 if (ret) 356 return ret; 357 358 return intel_pmt_dev_register(entry, ns, dev); 359 } 360 EXPORT_SYMBOL_NS_GPL(intel_pmt_dev_create, INTEL_PMT); 361 362 void intel_pmt_dev_destroy(struct intel_pmt_entry *entry, 363 struct intel_pmt_namespace *ns) 364 { 365 struct device *dev = kobj_to_dev(entry->kobj); 366 367 if (entry->size) 368 sysfs_remove_bin_file(entry->kobj, &entry->pmt_bin_attr); 369 370 if (ns->attr_grp) 371 sysfs_remove_group(entry->kobj, ns->attr_grp); 372 373 device_unregister(dev); 374 xa_erase(ns->xa, entry->devid); 375 } 376 EXPORT_SYMBOL_NS_GPL(intel_pmt_dev_destroy, INTEL_PMT); 377 378 static int __init pmt_class_init(void) 379 { 380 return class_register(&intel_pmt_class); 381 } 382 383 static void __exit pmt_class_exit(void) 384 { 385 class_unregister(&intel_pmt_class); 386 } 387 388 module_init(pmt_class_init); 389 module_exit(pmt_class_exit); 390 391 MODULE_AUTHOR("Alexander Duyck <alexander.h.duyck@linux.intel.com>"); 392 MODULE_DESCRIPTION("Intel PMT Class driver"); 393 MODULE_LICENSE("GPL v2"); 394