1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* Copyright(c) 2022 Intel Corporation. */ 3 4 #ifndef _IFS_H_ 5 #define _IFS_H_ 6 7 /** 8 * DOC: In-Field Scan 9 * 10 * ============= 11 * In-Field Scan 12 * ============= 13 * 14 * Introduction 15 * ------------ 16 * 17 * In Field Scan (IFS) is a hardware feature to run circuit level tests on 18 * a CPU core to detect problems that are not caught by parity or ECC checks. 19 * Future CPUs will support more than one type of test which will show up 20 * with a new platform-device instance-id. 21 * 22 * 23 * IFS Image 24 * --------- 25 * 26 * Intel provides a firmware file containing the scan tests via 27 * github [#f1]_. Similar to microcode there is a separate file for each 28 * family-model-stepping. IFS Images are not applicable for some test types. 29 * Wherever applicable the sysfs directory would provide a "current_batch" file 30 * (see below) for loading the image. 31 * 32 * 33 * IFS Image Loading 34 * ----------------- 35 * 36 * The driver loads the tests into memory reserved BIOS local to each CPU 37 * socket in a two step process using writes to MSRs to first load the 38 * SHA hashes for the test. Then the tests themselves. Status MSRs provide 39 * feedback on the success/failure of these steps. 40 * 41 * The test files are kept in a fixed location: /lib/firmware/intel/ifs_<n>/ 42 * For e.g if there are 3 test files, they would be named in the following 43 * fashion: 44 * ff-mm-ss-01.scan 45 * ff-mm-ss-02.scan 46 * ff-mm-ss-03.scan 47 * (where ff refers to family, mm indicates model and ss indicates stepping) 48 * 49 * A different test file can be loaded by writing the numerical portion 50 * (e.g 1, 2 or 3 in the above scenario) into the curent_batch file. 51 * To load ff-mm-ss-02.scan, the following command can be used:: 52 * 53 * # echo 2 > /sys/devices/virtual/misc/intel_ifs_<n>/current_batch 54 * 55 * The above file can also be read to know the currently loaded image. 56 * 57 * Running tests 58 * ------------- 59 * 60 * Tests are run by the driver synchronizing execution of all threads on a 61 * core and then writing to the ACTIVATE_SCAN MSR on all threads. Instruction 62 * execution continues when: 63 * 64 * 1) All tests have completed. 65 * 2) Execution was interrupted. 66 * 3) A test detected a problem. 67 * 68 * Note that ALL THREADS ON THE CORE ARE EFFECTIVELY OFFLINE FOR THE 69 * DURATION OF THE TEST. This can be up to 200 milliseconds. If the system 70 * is running latency sensitive applications that cannot tolerate an 71 * interruption of this magnitude, the system administrator must arrange 72 * to migrate those applications to other cores before running a core test. 73 * It may also be necessary to redirect interrupts to other CPUs. 74 * 75 * In all cases reading the corresponding test's STATUS MSR provides details on what 76 * happened. The driver makes the value of this MSR visible to applications 77 * via the "details" file (see below). Interrupted tests may be restarted. 78 * 79 * The IFS driver provides sysfs interfaces via /sys/devices/virtual/misc/intel_ifs_<n>/ 80 * to control execution: 81 * 82 * Test a specific core:: 83 * 84 * # echo <cpu#> > /sys/devices/virtual/misc/intel_ifs_<n>/run_test 85 * 86 * when HT is enabled any of the sibling cpu# can be specified to test 87 * its corresponding physical core. Since the tests are per physical core, 88 * the result of testing any thread is same. All siblings must be online 89 * to run a core test. It is only necessary to test one thread. 90 * 91 * For e.g. to test core corresponding to cpu5 92 * 93 * # echo 5 > /sys/devices/virtual/misc/intel_ifs_<n>/run_test 94 * 95 * Results of the last test is provided in /sys:: 96 * 97 * $ cat /sys/devices/virtual/misc/intel_ifs_<n>/status 98 * pass 99 * 100 * Status can be one of pass, fail, untested 101 * 102 * Additional details of the last test is provided by the details file:: 103 * 104 * $ cat /sys/devices/virtual/misc/intel_ifs_<n>/details 105 * 0x8081 106 * 107 * The details file reports the hex value of the test specific status MSR. 108 * Hardware defined error codes are documented in volume 4 of the Intel 109 * Software Developer's Manual but the error_code field may contain one of 110 * the following driver defined software codes: 111 * 112 * +------+--------------------+ 113 * | 0xFD | Software timeout | 114 * +------+--------------------+ 115 * | 0xFE | Partial completion | 116 * +------+--------------------+ 117 * 118 * Driver design choices 119 * --------------------- 120 * 121 * 1) The ACTIVATE_SCAN MSR allows for running any consecutive subrange of 122 * available tests. But the driver always tries to run all tests and only 123 * uses the subrange feature to restart an interrupted test. 124 * 125 * 2) Hardware allows for some number of cores to be tested in parallel. 126 * The driver does not make use of this, it only tests one core at a time. 127 * 128 * .. [#f1] https://github.com/intel/TBD 129 * 130 * 131 * Structural Based Functional Test at Field (SBAF): 132 * ------------------------------------------------- 133 * 134 * SBAF is a new type of testing that provides comprehensive core test 135 * coverage complementing Scan at Field (SAF) testing. SBAF mimics the 136 * manufacturing screening environment and leverages the same test suite. 137 * It makes use of Design For Test (DFT) observation sites and features 138 * to maximize coverage in minimum time. 139 * 140 * Similar to the SAF test, SBAF isolates the core under test from the 141 * rest of the system during execution. Upon completion, the core 142 * seamlessly resets to its pre-test state and resumes normal operation. 143 * Any machine checks or hangs encountered during the test are confined to 144 * the isolated core, preventing disruption to the overall system. 145 * 146 * Like the SAF test, the SBAF test is also divided into multiple batches, 147 * and each batch test can take hundreds of milliseconds (100-200 ms) to 148 * complete. If such a lengthy interruption is undesirable, it is 149 * recommended to relocate the time-sensitive applications to other cores. 150 */ 151 #include <linux/device.h> 152 #include <linux/miscdevice.h> 153 154 #define MSR_ARRAY_BIST 0x00000105 155 156 #define MSR_COPY_SBAF_HASHES 0x000002b8 157 #define MSR_SBAF_HASHES_STATUS 0x000002b9 158 #define MSR_AUTHENTICATE_AND_COPY_SBAF_CHUNK 0x000002ba 159 #define MSR_SBAF_CHUNKS_AUTHENTICATION_STATUS 0x000002bb 160 #define MSR_ACTIVATE_SBAF 0x000002bc 161 #define MSR_SBAF_STATUS 0x000002bd 162 163 #define MSR_COPY_SCAN_HASHES 0x000002c2 164 #define MSR_SCAN_HASHES_STATUS 0x000002c3 165 #define MSR_AUTHENTICATE_AND_COPY_CHUNK 0x000002c4 166 #define MSR_CHUNKS_AUTHENTICATION_STATUS 0x000002c5 167 #define MSR_ACTIVATE_SCAN 0x000002c6 168 #define MSR_SCAN_STATUS 0x000002c7 169 #define MSR_ARRAY_TRIGGER 0x000002d6 170 #define MSR_ARRAY_STATUS 0x000002d7 171 #define MSR_SAF_CTRL 0x000004f0 172 #define MSR_SBAF_CTRL 0x000004f8 173 174 #define SCAN_NOT_TESTED 0 175 #define SCAN_TEST_PASS 1 176 #define SCAN_TEST_FAIL 2 177 178 #define IFS_TYPE_SAF 0 179 #define IFS_TYPE_ARRAY_BIST 1 180 #define IFS_TYPE_SBAF 2 181 182 #define ARRAY_GEN0 0 183 #define ARRAY_GEN1 1 184 185 /* MSR_SCAN_HASHES_STATUS bit fields */ 186 union ifs_scan_hashes_status { 187 u64 data; 188 struct { 189 u32 chunk_size :16; 190 u32 num_chunks :8; 191 u32 rsvd1 :8; 192 u32 error_code :8; 193 u32 rsvd2 :11; 194 u32 max_core_limit :12; 195 u32 valid :1; 196 }; 197 }; 198 199 union ifs_scan_hashes_status_gen2 { 200 u64 data; 201 struct { 202 u16 chunk_size; 203 u16 num_chunks; 204 u32 error_code :8; 205 u32 chunks_in_stride :9; 206 u32 rsvd :2; 207 u32 max_core_limit :12; 208 u32 valid :1; 209 }; 210 }; 211 212 /* MSR_CHUNKS_AUTH_STATUS bit fields */ 213 union ifs_chunks_auth_status { 214 u64 data; 215 struct { 216 u32 valid_chunks :8; 217 u32 total_chunks :8; 218 u32 rsvd1 :16; 219 u32 error_code :8; 220 u32 rsvd2 :24; 221 }; 222 }; 223 224 union ifs_chunks_auth_status_gen2 { 225 u64 data; 226 struct { 227 u16 valid_chunks; 228 u16 total_chunks; 229 u32 error_code :8; 230 u32 rsvd2 :8; 231 u32 max_bundle :16; 232 }; 233 }; 234 235 /* MSR_ACTIVATE_SCAN bit fields */ 236 union ifs_scan { 237 u64 data; 238 struct { 239 union { 240 struct { 241 u8 start; 242 u8 stop; 243 u16 rsvd; 244 } gen0; 245 struct { 246 u16 start; 247 u16 stop; 248 } gen2; 249 }; 250 u32 delay :31; 251 u32 sigmce :1; 252 }; 253 }; 254 255 /* MSR_SCAN_STATUS bit fields */ 256 union ifs_status { 257 u64 data; 258 struct { 259 union { 260 struct { 261 u8 chunk_num; 262 u8 chunk_stop_index; 263 u16 rsvd1; 264 } gen0; 265 struct { 266 u16 chunk_num; 267 u16 chunk_stop_index; 268 } gen2; 269 }; 270 u32 error_code :8; 271 u32 rsvd2 :22; 272 u32 control_error :1; 273 u32 signature_error :1; 274 }; 275 }; 276 277 /* MSR_ARRAY_BIST bit fields */ 278 union ifs_array { 279 u64 data; 280 struct { 281 u32 array_bitmask; 282 u16 array_bank; 283 u16 rsvd :15; 284 u16 ctrl_result :1; 285 }; 286 }; 287 288 /* MSR_ACTIVATE_SBAF bit fields */ 289 union ifs_sbaf { 290 u64 data; 291 struct { 292 u32 bundle_idx :9; 293 u32 rsvd1 :5; 294 u32 pgm_idx :2; 295 u32 rsvd2 :16; 296 u32 delay :31; 297 u32 sigmce :1; 298 }; 299 }; 300 301 /* MSR_SBAF_STATUS bit fields */ 302 union ifs_sbaf_status { 303 u64 data; 304 struct { 305 u32 bundle_idx :9; 306 u32 rsvd1 :5; 307 u32 pgm_idx :2; 308 u32 rsvd2 :16; 309 u32 error_code :8; 310 u32 rsvd3 :21; 311 u32 test_fail :1; 312 u32 sbaf_status :2; 313 }; 314 }; 315 316 /* 317 * Driver populated error-codes 318 * 0xFD: Test timed out before completing all the chunks. 319 * 0xFE: not all scan chunks were executed. Maximum forward progress retries exceeded. 320 */ 321 #define IFS_SW_TIMEOUT 0xFD 322 #define IFS_SW_PARTIAL_COMPLETION 0xFE 323 324 #define IFS_SUFFIX_SZ 5 325 326 struct ifs_test_caps { 327 int integrity_cap_bit; 328 int test_num; 329 char image_suffix[IFS_SUFFIX_SZ]; 330 }; 331 332 /** 333 * struct ifs_test_msrs - MSRs used in IFS tests 334 * @copy_hashes: Copy test hash data 335 * @copy_hashes_status: Status of copied test hash data 336 * @copy_chunks: Copy chunks of the test data 337 * @copy_chunks_status: Status of the copied test data chunks 338 * @test_ctrl: Control the test attributes 339 */ 340 struct ifs_test_msrs { 341 u32 copy_hashes; 342 u32 copy_hashes_status; 343 u32 copy_chunks; 344 u32 copy_chunks_status; 345 u32 test_ctrl; 346 }; 347 348 /** 349 * struct ifs_data - attributes related to intel IFS driver 350 * @loaded_version: stores the currently loaded ifs image version. 351 * @loaded: If a valid test binary has been loaded into the memory 352 * @loading_error: Error occurred on another CPU while loading image 353 * @valid_chunks: number of chunks which could be validated. 354 * @status: it holds simple status pass/fail/untested 355 * @scan_details: opaque scan status code from h/w 356 * @cur_batch: number indicating the currently loaded test file 357 * @generation: IFS test generation enumerated by hardware 358 * @chunk_size: size of a test chunk 359 * @array_gen: test generation of array test 360 * @max_bundle: maximum bundle index 361 */ 362 struct ifs_data { 363 int loaded_version; 364 bool loaded; 365 bool loading_error; 366 int valid_chunks; 367 int status; 368 u64 scan_details; 369 u32 cur_batch; 370 u32 generation; 371 u32 chunk_size; 372 u32 array_gen; 373 u32 max_bundle; 374 }; 375 376 struct ifs_work { 377 struct work_struct w; 378 struct device *dev; 379 }; 380 381 struct ifs_device { 382 const struct ifs_test_caps *test_caps; 383 const struct ifs_test_msrs *test_msrs; 384 struct ifs_data rw_data; 385 struct miscdevice misc; 386 }; 387 388 static inline struct ifs_data *ifs_get_data(struct device *dev) 389 { 390 struct miscdevice *m = dev_get_drvdata(dev); 391 struct ifs_device *d = container_of(m, struct ifs_device, misc); 392 393 return &d->rw_data; 394 } 395 396 static inline const struct ifs_test_caps *ifs_get_test_caps(struct device *dev) 397 { 398 struct miscdevice *m = dev_get_drvdata(dev); 399 struct ifs_device *d = container_of(m, struct ifs_device, misc); 400 401 return d->test_caps; 402 } 403 404 static inline const struct ifs_test_msrs *ifs_get_test_msrs(struct device *dev) 405 { 406 struct miscdevice *m = dev_get_drvdata(dev); 407 struct ifs_device *d = container_of(m, struct ifs_device, misc); 408 409 return d->test_msrs; 410 } 411 412 extern bool *ifs_pkg_auth; 413 int ifs_load_firmware(struct device *dev); 414 int do_core_test(int cpu, struct device *dev); 415 extern struct attribute *plat_ifs_attrs[]; 416 extern struct attribute *plat_ifs_array_attrs[]; 417 418 #endif 419