| 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
| 2 | /* |
| 3 | * |
| 4 | * Procedures for interfacing to the RTAS on CHRP machines. |
| 5 | * |
| 6 | * Peter Bergner, IBM March 2001. |
| 7 | * Copyright (C) 2001 IBM. |
| 8 | */ |
| 9 | |
| 10 | #define pr_fmt(fmt) "rtas: " fmt |
| 11 | |
| 12 | #include <linux/bsearch.h> |
| 13 | #include <linux/capability.h> |
| 14 | #include <linux/delay.h> |
| 15 | #include <linux/export.h> |
| 16 | #include <linux/init.h> |
| 17 | #include <linux/kconfig.h> |
| 18 | #include <linux/kernel.h> |
| 19 | #include <linux/lockdep.h> |
| 20 | #include <linux/memblock.h> |
| 21 | #include <linux/mutex.h> |
| 22 | #include <linux/nospec.h> |
| 23 | #include <linux/of.h> |
| 24 | #include <linux/of_fdt.h> |
| 25 | #include <linux/reboot.h> |
| 26 | #include <linux/sched.h> |
| 27 | #include <linux/security.h> |
| 28 | #include <linux/slab.h> |
| 29 | #include <linux/spinlock.h> |
| 30 | #include <linux/stdarg.h> |
| 31 | #include <linux/syscalls.h> |
| 32 | #include <linux/types.h> |
| 33 | #include <linux/uaccess.h> |
| 34 | #include <linux/xarray.h> |
| 35 | |
| 36 | #include <asm/delay.h> |
| 37 | #include <asm/firmware.h> |
| 38 | #include <asm/interrupt.h> |
| 39 | #include <asm/machdep.h> |
| 40 | #include <asm/mmu.h> |
| 41 | #include <asm/page.h> |
| 42 | #include <asm/rtas-work-area.h> |
| 43 | #include <asm/rtas.h> |
| 44 | #include <asm/time.h> |
| 45 | #include <asm/trace.h> |
| 46 | #include <asm/udbg.h> |
| 47 | |
| 48 | struct rtas_filter { |
| 49 | /* Indexes into the args buffer, -1 if not used */ |
| 50 | const int buf_idx1; |
| 51 | const int size_idx1; |
| 52 | const int buf_idx2; |
| 53 | const int size_idx2; |
| 54 | /* |
| 55 | * Assumed buffer size per the spec if the function does not |
| 56 | * have a size parameter, e.g. ibm,errinjct. 0 if unused. |
| 57 | */ |
| 58 | const int fixed_size; |
| 59 | }; |
| 60 | |
| 61 | /** |
| 62 | * struct rtas_function - Descriptor for RTAS functions. |
| 63 | * |
| 64 | * @token: Value of @name if it exists under the /rtas node. |
| 65 | * @name: Function name. |
| 66 | * @filter: If non-NULL, invoking this function via the rtas syscall is |
| 67 | * generally allowed, and @filter describes constraints on the |
| 68 | * arguments. See also @banned_for_syscall_on_le. |
| 69 | * @banned_for_syscall_on_le: Set when call via sys_rtas is generally allowed |
| 70 | * but specifically restricted on ppc64le. Such |
| 71 | * functions are believed to have no users on |
| 72 | * ppc64le, and we want to keep it that way. It does |
| 73 | * not make sense for this to be set when @filter |
| 74 | * is NULL. |
| 75 | * @lock: Pointer to an optional dedicated per-function mutex. This |
| 76 | * should be set for functions that require multiple calls in |
| 77 | * sequence to complete a single operation, and such sequences |
| 78 | * will disrupt each other if allowed to interleave. Users of |
| 79 | * this function are required to hold the associated lock for |
| 80 | * the duration of the call sequence. Add an explanatory |
| 81 | * comment to the function table entry if setting this member. |
| 82 | */ |
| 83 | struct rtas_function { |
| 84 | s32 token; |
| 85 | const bool banned_for_syscall_on_le:1; |
| 86 | const char * const name; |
| 87 | const struct rtas_filter *filter; |
| 88 | struct mutex *lock; |
| 89 | }; |
| 90 | |
| 91 | /* |
| 92 | * Per-function locks for sequence-based RTAS functions. |
| 93 | */ |
| 94 | static DEFINE_MUTEX(rtas_ibm_activate_firmware_lock); |
| 95 | static DEFINE_MUTEX(rtas_ibm_get_dynamic_sensor_state_lock); |
| 96 | static DEFINE_MUTEX(rtas_ibm_get_indices_lock); |
| 97 | static DEFINE_MUTEX(rtas_ibm_lpar_perftools_lock); |
| 98 | static DEFINE_MUTEX(rtas_ibm_physical_attestation_lock); |
| 99 | static DEFINE_MUTEX(rtas_ibm_set_dynamic_indicator_lock); |
| 100 | DEFINE_MUTEX(rtas_ibm_get_vpd_lock); |
| 101 | |
| 102 | static struct rtas_function rtas_function_table[] __ro_after_init = { |
| 103 | [RTAS_FNIDX__CHECK_EXCEPTION] = { |
| 104 | .name = "check-exception", |
| 105 | }, |
| 106 | [RTAS_FNIDX__DISPLAY_CHARACTER] = { |
| 107 | .name = "display-character", |
| 108 | .filter = &(const struct rtas_filter) { |
| 109 | .buf_idx1 = -1, .size_idx1 = -1, |
| 110 | .buf_idx2 = -1, .size_idx2 = -1, |
| 111 | }, |
| 112 | }, |
| 113 | [RTAS_FNIDX__EVENT_SCAN] = { |
| 114 | .name = "event-scan", |
| 115 | }, |
| 116 | [RTAS_FNIDX__FREEZE_TIME_BASE] = { |
| 117 | .name = "freeze-time-base", |
| 118 | }, |
| 119 | [RTAS_FNIDX__GET_POWER_LEVEL] = { |
| 120 | .name = "get-power-level", |
| 121 | .filter = &(const struct rtas_filter) { |
| 122 | .buf_idx1 = -1, .size_idx1 = -1, |
| 123 | .buf_idx2 = -1, .size_idx2 = -1, |
| 124 | }, |
| 125 | }, |
| 126 | [RTAS_FNIDX__GET_SENSOR_STATE] = { |
| 127 | .name = "get-sensor-state", |
| 128 | .filter = &(const struct rtas_filter) { |
| 129 | .buf_idx1 = -1, .size_idx1 = -1, |
| 130 | .buf_idx2 = -1, .size_idx2 = -1, |
| 131 | }, |
| 132 | }, |
| 133 | [RTAS_FNIDX__GET_TERM_CHAR] = { |
| 134 | .name = "get-term-char", |
| 135 | }, |
| 136 | [RTAS_FNIDX__GET_TIME_OF_DAY] = { |
| 137 | .name = "get-time-of-day", |
| 138 | .filter = &(const struct rtas_filter) { |
| 139 | .buf_idx1 = -1, .size_idx1 = -1, |
| 140 | .buf_idx2 = -1, .size_idx2 = -1, |
| 141 | }, |
| 142 | }, |
| 143 | [RTAS_FNIDX__IBM_ACTIVATE_FIRMWARE] = { |
| 144 | .name = "ibm,activate-firmware", |
| 145 | .filter = &(const struct rtas_filter) { |
| 146 | .buf_idx1 = -1, .size_idx1 = -1, |
| 147 | .buf_idx2 = -1, .size_idx2 = -1, |
| 148 | }, |
| 149 | /* |
| 150 | * PAPR+ as of v2.13 doesn't explicitly impose any |
| 151 | * restriction, but this typically requires multiple |
| 152 | * calls before success, and there's no reason to |
| 153 | * allow sequences to interleave. |
| 154 | */ |
| 155 | .lock = &rtas_ibm_activate_firmware_lock, |
| 156 | }, |
| 157 | [RTAS_FNIDX__IBM_CBE_START_PTCAL] = { |
| 158 | .name = "ibm,cbe-start-ptcal", |
| 159 | }, |
| 160 | [RTAS_FNIDX__IBM_CBE_STOP_PTCAL] = { |
| 161 | .name = "ibm,cbe-stop-ptcal", |
| 162 | }, |
| 163 | [RTAS_FNIDX__IBM_CHANGE_MSI] = { |
| 164 | .name = "ibm,change-msi", |
| 165 | }, |
| 166 | [RTAS_FNIDX__IBM_CLOSE_ERRINJCT] = { |
| 167 | .name = "ibm,close-errinjct", |
| 168 | .filter = &(const struct rtas_filter) { |
| 169 | .buf_idx1 = -1, .size_idx1 = -1, |
| 170 | .buf_idx2 = -1, .size_idx2 = -1, |
| 171 | }, |
| 172 | }, |
| 173 | [RTAS_FNIDX__IBM_CONFIGURE_BRIDGE] = { |
| 174 | .name = "ibm,configure-bridge", |
| 175 | }, |
| 176 | [RTAS_FNIDX__IBM_CONFIGURE_CONNECTOR] = { |
| 177 | .name = "ibm,configure-connector", |
| 178 | .filter = &(const struct rtas_filter) { |
| 179 | .buf_idx1 = 0, .size_idx1 = -1, |
| 180 | .buf_idx2 = 1, .size_idx2 = -1, |
| 181 | .fixed_size = 4096, |
| 182 | }, |
| 183 | }, |
| 184 | [RTAS_FNIDX__IBM_CONFIGURE_KERNEL_DUMP] = { |
| 185 | .name = "ibm,configure-kernel-dump", |
| 186 | }, |
| 187 | [RTAS_FNIDX__IBM_CONFIGURE_PE] = { |
| 188 | .name = "ibm,configure-pe", |
| 189 | }, |
| 190 | [RTAS_FNIDX__IBM_CREATE_PE_DMA_WINDOW] = { |
| 191 | .name = "ibm,create-pe-dma-window", |
| 192 | }, |
| 193 | [RTAS_FNIDX__IBM_DISPLAY_MESSAGE] = { |
| 194 | .name = "ibm,display-message", |
| 195 | .filter = &(const struct rtas_filter) { |
| 196 | .buf_idx1 = 0, .size_idx1 = -1, |
| 197 | .buf_idx2 = -1, .size_idx2 = -1, |
| 198 | }, |
| 199 | }, |
| 200 | [RTAS_FNIDX__IBM_ERRINJCT] = { |
| 201 | .name = "ibm,errinjct", |
| 202 | .filter = &(const struct rtas_filter) { |
| 203 | .buf_idx1 = 2, .size_idx1 = -1, |
| 204 | .buf_idx2 = -1, .size_idx2 = -1, |
| 205 | .fixed_size = 1024, |
| 206 | }, |
| 207 | }, |
| 208 | [RTAS_FNIDX__IBM_EXTI2C] = { |
| 209 | .name = "ibm,exti2c", |
| 210 | }, |
| 211 | [RTAS_FNIDX__IBM_GET_CONFIG_ADDR_INFO] = { |
| 212 | .name = "ibm,get-config-addr-info", |
| 213 | }, |
| 214 | [RTAS_FNIDX__IBM_GET_CONFIG_ADDR_INFO2] = { |
| 215 | .name = "ibm,get-config-addr-info2", |
| 216 | .filter = &(const struct rtas_filter) { |
| 217 | .buf_idx1 = -1, .size_idx1 = -1, |
| 218 | .buf_idx2 = -1, .size_idx2 = -1, |
| 219 | }, |
| 220 | }, |
| 221 | [RTAS_FNIDX__IBM_GET_DYNAMIC_SENSOR_STATE] = { |
| 222 | .name = "ibm,get-dynamic-sensor-state", |
| 223 | .filter = &(const struct rtas_filter) { |
| 224 | .buf_idx1 = 1, .size_idx1 = -1, |
| 225 | .buf_idx2 = -1, .size_idx2 = -1, |
| 226 | }, |
| 227 | /* |
| 228 | * PAPR+ v2.13 R1–7.3.19–3 is explicit that the OS |
| 229 | * must not call ibm,get-dynamic-sensor-state with |
| 230 | * different inputs until a non-retry status has been |
| 231 | * returned. |
| 232 | */ |
| 233 | .lock = &rtas_ibm_get_dynamic_sensor_state_lock, |
| 234 | }, |
| 235 | [RTAS_FNIDX__IBM_GET_INDICES] = { |
| 236 | .name = "ibm,get-indices", |
| 237 | .filter = &(const struct rtas_filter) { |
| 238 | .buf_idx1 = 2, .size_idx1 = 3, |
| 239 | .buf_idx2 = -1, .size_idx2 = -1, |
| 240 | }, |
| 241 | /* |
| 242 | * PAPR+ v2.13 R1–7.3.17–2 says that the OS must not |
| 243 | * interleave ibm,get-indices call sequences with |
| 244 | * different inputs. |
| 245 | */ |
| 246 | .lock = &rtas_ibm_get_indices_lock, |
| 247 | }, |
| 248 | [RTAS_FNIDX__IBM_GET_RIO_TOPOLOGY] = { |
| 249 | .name = "ibm,get-rio-topology", |
| 250 | }, |
| 251 | [RTAS_FNIDX__IBM_GET_SYSTEM_PARAMETER] = { |
| 252 | .name = "ibm,get-system-parameter", |
| 253 | .filter = &(const struct rtas_filter) { |
| 254 | .buf_idx1 = 1, .size_idx1 = 2, |
| 255 | .buf_idx2 = -1, .size_idx2 = -1, |
| 256 | }, |
| 257 | }, |
| 258 | [RTAS_FNIDX__IBM_GET_VPD] = { |
| 259 | .name = "ibm,get-vpd", |
| 260 | .filter = &(const struct rtas_filter) { |
| 261 | .buf_idx1 = 0, .size_idx1 = -1, |
| 262 | .buf_idx2 = 1, .size_idx2 = 2, |
| 263 | }, |
| 264 | /* |
| 265 | * PAPR+ v2.13 R1–7.3.20–4 indicates that sequences |
| 266 | * should not be allowed to interleave. |
| 267 | */ |
| 268 | .lock = &rtas_ibm_get_vpd_lock, |
| 269 | }, |
| 270 | [RTAS_FNIDX__IBM_GET_XIVE] = { |
| 271 | .name = "ibm,get-xive", |
| 272 | }, |
| 273 | [RTAS_FNIDX__IBM_INT_OFF] = { |
| 274 | .name = "ibm,int-off", |
| 275 | }, |
| 276 | [RTAS_FNIDX__IBM_INT_ON] = { |
| 277 | .name = "ibm,int-on", |
| 278 | }, |
| 279 | [RTAS_FNIDX__IBM_IO_QUIESCE_ACK] = { |
| 280 | .name = "ibm,io-quiesce-ack", |
| 281 | }, |
| 282 | [RTAS_FNIDX__IBM_LPAR_PERFTOOLS] = { |
| 283 | .name = "ibm,lpar-perftools", |
| 284 | .filter = &(const struct rtas_filter) { |
| 285 | .buf_idx1 = 2, .size_idx1 = 3, |
| 286 | .buf_idx2 = -1, .size_idx2 = -1, |
| 287 | }, |
| 288 | /* |
| 289 | * PAPR+ v2.13 R1–7.3.26–6 says the OS should allow |
| 290 | * only one call sequence in progress at a time. |
| 291 | */ |
| 292 | .lock = &rtas_ibm_lpar_perftools_lock, |
| 293 | }, |
| 294 | [RTAS_FNIDX__IBM_MANAGE_FLASH_IMAGE] = { |
| 295 | .name = "ibm,manage-flash-image", |
| 296 | }, |
| 297 | [RTAS_FNIDX__IBM_MANAGE_STORAGE_PRESERVATION] = { |
| 298 | .name = "ibm,manage-storage-preservation", |
| 299 | }, |
| 300 | [RTAS_FNIDX__IBM_NMI_INTERLOCK] = { |
| 301 | .name = "ibm,nmi-interlock", |
| 302 | }, |
| 303 | [RTAS_FNIDX__IBM_NMI_REGISTER] = { |
| 304 | .name = "ibm,nmi-register", |
| 305 | }, |
| 306 | [RTAS_FNIDX__IBM_OPEN_ERRINJCT] = { |
| 307 | .name = "ibm,open-errinjct", |
| 308 | .filter = &(const struct rtas_filter) { |
| 309 | .buf_idx1 = -1, .size_idx1 = -1, |
| 310 | .buf_idx2 = -1, .size_idx2 = -1, |
| 311 | }, |
| 312 | }, |
| 313 | [RTAS_FNIDX__IBM_OPEN_SRIOV_ALLOW_UNFREEZE] = { |
| 314 | .name = "ibm,open-sriov-allow-unfreeze", |
| 315 | }, |
| 316 | [RTAS_FNIDX__IBM_OPEN_SRIOV_MAP_PE_NUMBER] = { |
| 317 | .name = "ibm,open-sriov-map-pe-number", |
| 318 | }, |
| 319 | [RTAS_FNIDX__IBM_OS_TERM] = { |
| 320 | .name = "ibm,os-term", |
| 321 | }, |
| 322 | [RTAS_FNIDX__IBM_PARTNER_CONTROL] = { |
| 323 | .name = "ibm,partner-control", |
| 324 | }, |
| 325 | [RTAS_FNIDX__IBM_PHYSICAL_ATTESTATION] = { |
| 326 | .name = "ibm,physical-attestation", |
| 327 | .filter = &(const struct rtas_filter) { |
| 328 | .buf_idx1 = 0, .size_idx1 = 1, |
| 329 | .buf_idx2 = -1, .size_idx2 = -1, |
| 330 | }, |
| 331 | /* |
| 332 | * This follows a sequence-based pattern similar to |
| 333 | * ibm,get-vpd et al. Since PAPR+ restricts |
| 334 | * interleaving call sequences for other functions of |
| 335 | * this style, assume the restriction applies here, |
| 336 | * even though it's not explicit in the spec. |
| 337 | */ |
| 338 | .lock = &rtas_ibm_physical_attestation_lock, |
| 339 | }, |
| 340 | [RTAS_FNIDX__IBM_PLATFORM_DUMP] = { |
| 341 | .name = "ibm,platform-dump", |
| 342 | .filter = &(const struct rtas_filter) { |
| 343 | .buf_idx1 = 4, .size_idx1 = 5, |
| 344 | .buf_idx2 = -1, .size_idx2 = -1, |
| 345 | }, |
| 346 | /* |
| 347 | * PAPR+ v2.13 7.3.3.4.1 indicates that concurrent |
| 348 | * sequences of ibm,platform-dump are allowed if they |
| 349 | * are operating on different dump tags. So leave the |
| 350 | * lock pointer unset for now. This may need |
| 351 | * reconsideration if kernel-internal users appear. |
| 352 | */ |
| 353 | }, |
| 354 | [RTAS_FNIDX__IBM_POWER_OFF_UPS] = { |
| 355 | .name = "ibm,power-off-ups", |
| 356 | }, |
| 357 | [RTAS_FNIDX__IBM_QUERY_INTERRUPT_SOURCE_NUMBER] = { |
| 358 | .name = "ibm,query-interrupt-source-number", |
| 359 | }, |
| 360 | [RTAS_FNIDX__IBM_QUERY_PE_DMA_WINDOW] = { |
| 361 | .name = "ibm,query-pe-dma-window", |
| 362 | }, |
| 363 | [RTAS_FNIDX__IBM_READ_PCI_CONFIG] = { |
| 364 | .name = "ibm,read-pci-config", |
| 365 | }, |
| 366 | [RTAS_FNIDX__IBM_READ_SLOT_RESET_STATE] = { |
| 367 | .name = "ibm,read-slot-reset-state", |
| 368 | .filter = &(const struct rtas_filter) { |
| 369 | .buf_idx1 = -1, .size_idx1 = -1, |
| 370 | .buf_idx2 = -1, .size_idx2 = -1, |
| 371 | }, |
| 372 | }, |
| 373 | [RTAS_FNIDX__IBM_READ_SLOT_RESET_STATE2] = { |
| 374 | .name = "ibm,read-slot-reset-state2", |
| 375 | }, |
| 376 | [RTAS_FNIDX__IBM_REMOVE_PE_DMA_WINDOW] = { |
| 377 | .name = "ibm,remove-pe-dma-window", |
| 378 | }, |
| 379 | [RTAS_FNIDX__IBM_RESET_PE_DMA_WINDOW] = { |
| 380 | /* |
| 381 | * Note: PAPR+ v2.13 7.3.31.4.1 spells this as |
| 382 | * "ibm,reset-pe-dma-windows" (plural), but RTAS |
| 383 | * implementations use the singular form in practice. |
| 384 | */ |
| 385 | .name = "ibm,reset-pe-dma-window", |
| 386 | }, |
| 387 | [RTAS_FNIDX__IBM_SCAN_LOG_DUMP] = { |
| 388 | .name = "ibm,scan-log-dump", |
| 389 | .filter = &(const struct rtas_filter) { |
| 390 | .buf_idx1 = 0, .size_idx1 = 1, |
| 391 | .buf_idx2 = -1, .size_idx2 = -1, |
| 392 | }, |
| 393 | }, |
| 394 | [RTAS_FNIDX__IBM_SET_DYNAMIC_INDICATOR] = { |
| 395 | .name = "ibm,set-dynamic-indicator", |
| 396 | .filter = &(const struct rtas_filter) { |
| 397 | .buf_idx1 = 2, .size_idx1 = -1, |
| 398 | .buf_idx2 = -1, .size_idx2 = -1, |
| 399 | }, |
| 400 | /* |
| 401 | * PAPR+ v2.13 R1–7.3.18–3 says the OS must not call |
| 402 | * this function with different inputs until a |
| 403 | * non-retry status has been returned. |
| 404 | */ |
| 405 | .lock = &rtas_ibm_set_dynamic_indicator_lock, |
| 406 | }, |
| 407 | [RTAS_FNIDX__IBM_SET_EEH_OPTION] = { |
| 408 | .name = "ibm,set-eeh-option", |
| 409 | .filter = &(const struct rtas_filter) { |
| 410 | .buf_idx1 = -1, .size_idx1 = -1, |
| 411 | .buf_idx2 = -1, .size_idx2 = -1, |
| 412 | }, |
| 413 | }, |
| 414 | [RTAS_FNIDX__IBM_SET_SLOT_RESET] = { |
| 415 | .name = "ibm,set-slot-reset", |
| 416 | }, |
| 417 | [RTAS_FNIDX__IBM_SET_SYSTEM_PARAMETER] = { |
| 418 | .name = "ibm,set-system-parameter", |
| 419 | .filter = &(const struct rtas_filter) { |
| 420 | .buf_idx1 = 1, .size_idx1 = -1, |
| 421 | .buf_idx2 = -1, .size_idx2 = -1, |
| 422 | }, |
| 423 | }, |
| 424 | [RTAS_FNIDX__IBM_SET_XIVE] = { |
| 425 | .name = "ibm,set-xive", |
| 426 | }, |
| 427 | [RTAS_FNIDX__IBM_SLOT_ERROR_DETAIL] = { |
| 428 | .name = "ibm,slot-error-detail", |
| 429 | }, |
| 430 | [RTAS_FNIDX__IBM_SUSPEND_ME] = { |
| 431 | .name = "ibm,suspend-me", |
| 432 | .banned_for_syscall_on_le = true, |
| 433 | .filter = &(const struct rtas_filter) { |
| 434 | .buf_idx1 = -1, .size_idx1 = -1, |
| 435 | .buf_idx2 = -1, .size_idx2 = -1, |
| 436 | }, |
| 437 | }, |
| 438 | [RTAS_FNIDX__IBM_TUNE_DMA_PARMS] = { |
| 439 | .name = "ibm,tune-dma-parms", |
| 440 | }, |
| 441 | [RTAS_FNIDX__IBM_UPDATE_FLASH_64_AND_REBOOT] = { |
| 442 | .name = "ibm,update-flash-64-and-reboot", |
| 443 | }, |
| 444 | [RTAS_FNIDX__IBM_UPDATE_NODES] = { |
| 445 | .name = "ibm,update-nodes", |
| 446 | .banned_for_syscall_on_le = true, |
| 447 | .filter = &(const struct rtas_filter) { |
| 448 | .buf_idx1 = 0, .size_idx1 = -1, |
| 449 | .buf_idx2 = -1, .size_idx2 = -1, |
| 450 | .fixed_size = 4096, |
| 451 | }, |
| 452 | }, |
| 453 | [RTAS_FNIDX__IBM_UPDATE_PROPERTIES] = { |
| 454 | .name = "ibm,update-properties", |
| 455 | .banned_for_syscall_on_le = true, |
| 456 | .filter = &(const struct rtas_filter) { |
| 457 | .buf_idx1 = 0, .size_idx1 = -1, |
| 458 | .buf_idx2 = -1, .size_idx2 = -1, |
| 459 | .fixed_size = 4096, |
| 460 | }, |
| 461 | }, |
| 462 | [RTAS_FNIDX__IBM_VALIDATE_FLASH_IMAGE] = { |
| 463 | .name = "ibm,validate-flash-image", |
| 464 | }, |
| 465 | [RTAS_FNIDX__IBM_WRITE_PCI_CONFIG] = { |
| 466 | .name = "ibm,write-pci-config", |
| 467 | }, |
| 468 | [RTAS_FNIDX__NVRAM_FETCH] = { |
| 469 | .name = "nvram-fetch", |
| 470 | }, |
| 471 | [RTAS_FNIDX__NVRAM_STORE] = { |
| 472 | .name = "nvram-store", |
| 473 | }, |
| 474 | [RTAS_FNIDX__POWER_OFF] = { |
| 475 | .name = "power-off", |
| 476 | }, |
| 477 | [RTAS_FNIDX__PUT_TERM_CHAR] = { |
| 478 | .name = "put-term-char", |
| 479 | }, |
| 480 | [RTAS_FNIDX__QUERY_CPU_STOPPED_STATE] = { |
| 481 | .name = "query-cpu-stopped-state", |
| 482 | }, |
| 483 | [RTAS_FNIDX__READ_PCI_CONFIG] = { |
| 484 | .name = "read-pci-config", |
| 485 | }, |
| 486 | [RTAS_FNIDX__RTAS_LAST_ERROR] = { |
| 487 | .name = "rtas-last-error", |
| 488 | }, |
| 489 | [RTAS_FNIDX__SET_INDICATOR] = { |
| 490 | .name = "set-indicator", |
| 491 | .filter = &(const struct rtas_filter) { |
| 492 | .buf_idx1 = -1, .size_idx1 = -1, |
| 493 | .buf_idx2 = -1, .size_idx2 = -1, |
| 494 | }, |
| 495 | }, |
| 496 | [RTAS_FNIDX__SET_POWER_LEVEL] = { |
| 497 | .name = "set-power-level", |
| 498 | .filter = &(const struct rtas_filter) { |
| 499 | .buf_idx1 = -1, .size_idx1 = -1, |
| 500 | .buf_idx2 = -1, .size_idx2 = -1, |
| 501 | }, |
| 502 | }, |
| 503 | [RTAS_FNIDX__SET_TIME_FOR_POWER_ON] = { |
| 504 | .name = "set-time-for-power-on", |
| 505 | .filter = &(const struct rtas_filter) { |
| 506 | .buf_idx1 = -1, .size_idx1 = -1, |
| 507 | .buf_idx2 = -1, .size_idx2 = -1, |
| 508 | }, |
| 509 | }, |
| 510 | [RTAS_FNIDX__SET_TIME_OF_DAY] = { |
| 511 | .name = "set-time-of-day", |
| 512 | .filter = &(const struct rtas_filter) { |
| 513 | .buf_idx1 = -1, .size_idx1 = -1, |
| 514 | .buf_idx2 = -1, .size_idx2 = -1, |
| 515 | }, |
| 516 | }, |
| 517 | [RTAS_FNIDX__START_CPU] = { |
| 518 | .name = "start-cpu", |
| 519 | }, |
| 520 | [RTAS_FNIDX__STOP_SELF] = { |
| 521 | .name = "stop-self", |
| 522 | }, |
| 523 | [RTAS_FNIDX__SYSTEM_REBOOT] = { |
| 524 | .name = "system-reboot", |
| 525 | }, |
| 526 | [RTAS_FNIDX__THAW_TIME_BASE] = { |
| 527 | .name = "thaw-time-base", |
| 528 | }, |
| 529 | [RTAS_FNIDX__WRITE_PCI_CONFIG] = { |
| 530 | .name = "write-pci-config", |
| 531 | }, |
| 532 | }; |
| 533 | |
| 534 | #define for_each_rtas_function(funcp) \ |
| 535 | for (funcp = &rtas_function_table[0]; \ |
| 536 | funcp < &rtas_function_table[ARRAY_SIZE(rtas_function_table)]; \ |
| 537 | ++funcp) |
| 538 | |
| 539 | /* |
| 540 | * Nearly all RTAS calls need to be serialized. All uses of the |
| 541 | * default rtas_args block must hold rtas_lock. |
| 542 | * |
| 543 | * Exceptions to the RTAS serialization requirement (e.g. stop-self) |
| 544 | * must use a separate rtas_args structure. |
| 545 | */ |
| 546 | static DEFINE_RAW_SPINLOCK(rtas_lock); |
| 547 | static struct rtas_args rtas_args; |
| 548 | |
| 549 | /** |
| 550 | * rtas_function_token() - RTAS function token lookup. |
| 551 | * @handle: Function handle, e.g. RTAS_FN_EVENT_SCAN. |
| 552 | * |
| 553 | * Context: Any context. |
| 554 | * Return: the token value for the function if implemented by this platform, |
| 555 | * otherwise RTAS_UNKNOWN_SERVICE. |
| 556 | */ |
| 557 | s32 rtas_function_token(const rtas_fn_handle_t handle) |
| 558 | { |
| 559 | const size_t index = handle.index; |
| 560 | const bool out_of_bounds = index >= ARRAY_SIZE(rtas_function_table); |
| 561 | |
| 562 | if (WARN_ONCE(out_of_bounds, "invalid function index %zu", index)) |
| 563 | return RTAS_UNKNOWN_SERVICE; |
| 564 | /* |
| 565 | * Various drivers attempt token lookups on non-RTAS |
| 566 | * platforms. |
| 567 | */ |
| 568 | if (!rtas.dev) |
| 569 | return RTAS_UNKNOWN_SERVICE; |
| 570 | |
| 571 | return rtas_function_table[index].token; |
| 572 | } |
| 573 | EXPORT_SYMBOL_GPL(rtas_function_token); |
| 574 | |
| 575 | static int rtas_function_cmp(const void *a, const void *b) |
| 576 | { |
| 577 | const struct rtas_function *f1 = a; |
| 578 | const struct rtas_function *f2 = b; |
| 579 | |
| 580 | return strcmp(f1->name, f2->name); |
| 581 | } |
| 582 | |
| 583 | /* |
| 584 | * Boot-time initialization of the function table needs the lookup to |
| 585 | * return a non-const-qualified object. Use rtas_name_to_function() |
| 586 | * in all other contexts. |
| 587 | */ |
| 588 | static struct rtas_function *__rtas_name_to_function(const char *name) |
| 589 | { |
| 590 | const struct rtas_function key = { |
| 591 | .name = name, |
| 592 | }; |
| 593 | struct rtas_function *found; |
| 594 | |
| 595 | found = bsearch(&key, rtas_function_table, ARRAY_SIZE(rtas_function_table), |
| 596 | sizeof(rtas_function_table[0]), rtas_function_cmp); |
| 597 | |
| 598 | return found; |
| 599 | } |
| 600 | |
| 601 | static const struct rtas_function *rtas_name_to_function(const char *name) |
| 602 | { |
| 603 | return __rtas_name_to_function(name); |
| 604 | } |
| 605 | |
| 606 | static DEFINE_XARRAY(rtas_token_to_function_xarray); |
| 607 | |
| 608 | static int __init rtas_token_to_function_xarray_init(void) |
| 609 | { |
| 610 | const struct rtas_function *func; |
| 611 | int err = 0; |
| 612 | |
| 613 | for_each_rtas_function(func) { |
| 614 | const s32 token = func->token; |
| 615 | |
| 616 | if (token == RTAS_UNKNOWN_SERVICE) |
| 617 | continue; |
| 618 | |
| 619 | err = xa_err(xa_store(&rtas_token_to_function_xarray, |
| 620 | token, (void *)func, GFP_KERNEL)); |
| 621 | if (err) |
| 622 | break; |
| 623 | } |
| 624 | |
| 625 | return err; |
| 626 | } |
| 627 | arch_initcall(rtas_token_to_function_xarray_init); |
| 628 | |
| 629 | /* |
| 630 | * For use by sys_rtas(), where the token value is provided by user |
| 631 | * space and we don't want to warn on failed lookups. |
| 632 | */ |
| 633 | static const struct rtas_function *rtas_token_to_function_untrusted(s32 token) |
| 634 | { |
| 635 | return xa_load(&rtas_token_to_function_xarray, token); |
| 636 | } |
| 637 | |
| 638 | /* |
| 639 | * Reverse lookup for deriving the function descriptor from a |
| 640 | * known-good token value in contexts where the former is not already |
| 641 | * available. @token must be valid, e.g. derived from the result of a |
| 642 | * prior lookup against the function table. |
| 643 | */ |
| 644 | static const struct rtas_function *rtas_token_to_function(s32 token) |
| 645 | { |
| 646 | const struct rtas_function *func; |
| 647 | |
| 648 | if (WARN_ONCE(token < 0, "invalid token %d", token)) |
| 649 | return NULL; |
| 650 | |
| 651 | func = rtas_token_to_function_untrusted(token); |
| 652 | if (func) |
| 653 | return func; |
| 654 | /* |
| 655 | * Fall back to linear scan in case the reverse mapping hasn't |
| 656 | * been initialized yet. |
| 657 | */ |
| 658 | if (xa_empty(&rtas_token_to_function_xarray)) { |
| 659 | for_each_rtas_function(func) { |
| 660 | if (func->token == token) |
| 661 | return func; |
| 662 | } |
| 663 | } |
| 664 | |
| 665 | WARN_ONCE(true, "unexpected failed lookup for token %d", token); |
| 666 | return NULL; |
| 667 | } |
| 668 | |
| 669 | /* This is here deliberately so it's only used in this file */ |
| 670 | void enter_rtas(unsigned long); |
| 671 | |
| 672 | static void __do_enter_rtas(struct rtas_args *args) |
| 673 | { |
| 674 | enter_rtas(__pa(args)); |
| 675 | srr_regs_clobbered(); /* rtas uses SRRs, invalidate */ |
| 676 | } |
| 677 | |
| 678 | static void __do_enter_rtas_trace(struct rtas_args *args) |
| 679 | { |
| 680 | const struct rtas_function *func = rtas_token_to_function(be32_to_cpu(args->token)); |
| 681 | |
| 682 | /* |
| 683 | * If there is a per-function lock, it must be held by the |
| 684 | * caller. |
| 685 | */ |
| 686 | if (func->lock) |
| 687 | lockdep_assert_held(func->lock); |
| 688 | |
| 689 | if (args == &rtas_args) |
| 690 | lockdep_assert_held(&rtas_lock); |
| 691 | |
| 692 | trace_rtas_input(args, func->name); |
| 693 | trace_rtas_ll_entry(args); |
| 694 | |
| 695 | __do_enter_rtas(args); |
| 696 | |
| 697 | trace_rtas_ll_exit(args); |
| 698 | trace_rtas_output(args, func->name); |
| 699 | } |
| 700 | |
| 701 | static void do_enter_rtas(struct rtas_args *args) |
| 702 | { |
| 703 | const unsigned long msr = mfmsr(); |
| 704 | /* |
| 705 | * Situations where we want to skip any active tracepoints for |
| 706 | * safety reasons: |
| 707 | * |
| 708 | * 1. The last code executed on an offline CPU as it stops, |
| 709 | * i.e. we're about to call stop-self. The tracepoints' |
| 710 | * function name lookup uses xarray, which uses RCU, which |
| 711 | * isn't valid to call on an offline CPU. Any events |
| 712 | * emitted on an offline CPU will be discarded anyway. |
| 713 | * |
| 714 | * 2. In real mode, as when invoking ibm,nmi-interlock from |
| 715 | * the pseries MCE handler. We cannot count on trace |
| 716 | * buffers or the entries in rtas_token_to_function_xarray |
| 717 | * to be contained in the RMO. |
| 718 | */ |
| 719 | const unsigned long mask = MSR_IR | MSR_DR; |
| 720 | const bool can_trace = likely(cpu_online(raw_smp_processor_id()) && |
| 721 | (msr & mask) == mask); |
| 722 | /* |
| 723 | * Make sure MSR[RI] is currently enabled as it will be forced later |
| 724 | * in enter_rtas. |
| 725 | */ |
| 726 | BUG_ON(!(msr & MSR_RI)); |
| 727 | |
| 728 | BUG_ON(!irqs_disabled()); |
| 729 | |
| 730 | hard_irq_disable(); /* Ensure MSR[EE] is disabled on PPC64 */ |
| 731 | |
| 732 | if (can_trace) |
| 733 | __do_enter_rtas_trace(args); |
| 734 | else |
| 735 | __do_enter_rtas(args); |
| 736 | } |
| 737 | |
| 738 | struct rtas_t rtas; |
| 739 | |
| 740 | DEFINE_SPINLOCK(rtas_data_buf_lock); |
| 741 | EXPORT_SYMBOL_GPL(rtas_data_buf_lock); |
| 742 | |
| 743 | char rtas_data_buf[RTAS_DATA_BUF_SIZE] __aligned(SZ_4K); |
| 744 | EXPORT_SYMBOL_GPL(rtas_data_buf); |
| 745 | |
| 746 | unsigned long rtas_rmo_buf; |
| 747 | |
| 748 | /* |
| 749 | * If non-NULL, this gets called when the kernel terminates. |
| 750 | * This is done like this so rtas_flash can be a module. |
| 751 | */ |
| 752 | void (*rtas_flash_term_hook)(int); |
| 753 | EXPORT_SYMBOL_GPL(rtas_flash_term_hook); |
| 754 | |
| 755 | /* |
| 756 | * call_rtas_display_status and call_rtas_display_status_delay |
| 757 | * are designed only for very early low-level debugging, which |
| 758 | * is why the token is hard-coded to 10. |
| 759 | */ |
| 760 | static void call_rtas_display_status(unsigned char c) |
| 761 | { |
| 762 | unsigned long flags; |
| 763 | |
| 764 | if (!rtas.base) |
| 765 | return; |
| 766 | |
| 767 | raw_spin_lock_irqsave(&rtas_lock, flags); |
| 768 | rtas_call_unlocked(&rtas_args, 10, 1, 1, NULL, c); |
| 769 | raw_spin_unlock_irqrestore(&rtas_lock, flags); |
| 770 | } |
| 771 | |
| 772 | static void call_rtas_display_status_delay(char c) |
| 773 | { |
| 774 | static int pending_newline = 0; /* did last write end with unprinted newline? */ |
| 775 | static int width = 16; |
| 776 | |
| 777 | if (c == '\n') { |
| 778 | while (width-- > 0) |
| 779 | call_rtas_display_status(' '); |
| 780 | width = 16; |
| 781 | mdelay(500); |
| 782 | pending_newline = 1; |
| 783 | } else { |
| 784 | if (pending_newline) { |
| 785 | call_rtas_display_status('\r'); |
| 786 | call_rtas_display_status('\n'); |
| 787 | } |
| 788 | pending_newline = 0; |
| 789 | if (width--) { |
| 790 | call_rtas_display_status(c); |
| 791 | udelay(10000); |
| 792 | } |
| 793 | } |
| 794 | } |
| 795 | |
| 796 | void __init udbg_init_rtas_panel(void) |
| 797 | { |
| 798 | udbg_putc = call_rtas_display_status_delay; |
| 799 | } |
| 800 | |
| 801 | #ifdef CONFIG_UDBG_RTAS_CONSOLE |
| 802 | |
| 803 | /* If you think you're dying before early_init_dt_scan_rtas() does its |
| 804 | * work, you can hard code the token values for your firmware here and |
| 805 | * hardcode rtas.base/entry etc. |
| 806 | */ |
| 807 | static unsigned int rtas_putchar_token = RTAS_UNKNOWN_SERVICE; |
| 808 | static unsigned int rtas_getchar_token = RTAS_UNKNOWN_SERVICE; |
| 809 | |
| 810 | static void udbg_rtascon_putc(char c) |
| 811 | { |
| 812 | int tries; |
| 813 | |
| 814 | if (!rtas.base) |
| 815 | return; |
| 816 | |
| 817 | /* Add CRs before LFs */ |
| 818 | if (c == '\n') |
| 819 | udbg_rtascon_putc('\r'); |
| 820 | |
| 821 | /* if there is more than one character to be displayed, wait a bit */ |
| 822 | for (tries = 0; tries < 16; tries++) { |
| 823 | if (rtas_call(rtas_putchar_token, 1, 1, NULL, c) == 0) |
| 824 | break; |
| 825 | udelay(1000); |
| 826 | } |
| 827 | } |
| 828 | |
| 829 | static int udbg_rtascon_getc_poll(void) |
| 830 | { |
| 831 | int c; |
| 832 | |
| 833 | if (!rtas.base) |
| 834 | return -1; |
| 835 | |
| 836 | if (rtas_call(rtas_getchar_token, 0, 2, &c)) |
| 837 | return -1; |
| 838 | |
| 839 | return c; |
| 840 | } |
| 841 | |
| 842 | static int udbg_rtascon_getc(void) |
| 843 | { |
| 844 | int c; |
| 845 | |
| 846 | while ((c = udbg_rtascon_getc_poll()) == -1) |
| 847 | ; |
| 848 | |
| 849 | return c; |
| 850 | } |
| 851 | |
| 852 | |
| 853 | void __init udbg_init_rtas_console(void) |
| 854 | { |
| 855 | udbg_putc = udbg_rtascon_putc; |
| 856 | udbg_getc = udbg_rtascon_getc; |
| 857 | udbg_getc_poll = udbg_rtascon_getc_poll; |
| 858 | } |
| 859 | #endif /* CONFIG_UDBG_RTAS_CONSOLE */ |
| 860 | |
| 861 | void rtas_progress(char *s, unsigned short hex) |
| 862 | { |
| 863 | struct device_node *root; |
| 864 | int width; |
| 865 | const __be32 *p; |
| 866 | char *os; |
| 867 | static int display_character, set_indicator; |
| 868 | static int display_width, display_lines, form_feed; |
| 869 | static const int *row_width; |
| 870 | static DEFINE_SPINLOCK(progress_lock); |
| 871 | static int current_line; |
| 872 | static int pending_newline = 0; /* did last write end with unprinted newline? */ |
| 873 | |
| 874 | if (!rtas.base) |
| 875 | return; |
| 876 | |
| 877 | if (display_width == 0) { |
| 878 | display_width = 0x10; |
| 879 | if ((root = of_find_node_by_path("/rtas"))) { |
| 880 | if ((p = of_get_property(root, |
| 881 | "ibm,display-line-length", NULL))) |
| 882 | display_width = be32_to_cpu(*p); |
| 883 | if ((p = of_get_property(root, |
| 884 | "ibm,form-feed", NULL))) |
| 885 | form_feed = be32_to_cpu(*p); |
| 886 | if ((p = of_get_property(root, |
| 887 | "ibm,display-number-of-lines", NULL))) |
| 888 | display_lines = be32_to_cpu(*p); |
| 889 | row_width = of_get_property(root, |
| 890 | "ibm,display-truncation-length", NULL); |
| 891 | of_node_put(root); |
| 892 | } |
| 893 | display_character = rtas_function_token(RTAS_FN_DISPLAY_CHARACTER); |
| 894 | set_indicator = rtas_function_token(RTAS_FN_SET_INDICATOR); |
| 895 | } |
| 896 | |
| 897 | if (display_character == RTAS_UNKNOWN_SERVICE) { |
| 898 | /* use hex display if available */ |
| 899 | if (set_indicator != RTAS_UNKNOWN_SERVICE) |
| 900 | rtas_call(set_indicator, 3, 1, NULL, 6, 0, hex); |
| 901 | return; |
| 902 | } |
| 903 | |
| 904 | spin_lock(&progress_lock); |
| 905 | |
| 906 | /* |
| 907 | * Last write ended with newline, but we didn't print it since |
| 908 | * it would just clear the bottom line of output. Print it now |
| 909 | * instead. |
| 910 | * |
| 911 | * If no newline is pending and form feed is supported, clear the |
| 912 | * display with a form feed; otherwise, print a CR to start output |
| 913 | * at the beginning of the line. |
| 914 | */ |
| 915 | if (pending_newline) { |
| 916 | rtas_call(display_character, 1, 1, NULL, '\r'); |
| 917 | rtas_call(display_character, 1, 1, NULL, '\n'); |
| 918 | pending_newline = 0; |
| 919 | } else { |
| 920 | current_line = 0; |
| 921 | if (form_feed) |
| 922 | rtas_call(display_character, 1, 1, NULL, |
| 923 | (char)form_feed); |
| 924 | else |
| 925 | rtas_call(display_character, 1, 1, NULL, '\r'); |
| 926 | } |
| 927 | |
| 928 | if (row_width) |
| 929 | width = row_width[current_line]; |
| 930 | else |
| 931 | width = display_width; |
| 932 | os = s; |
| 933 | while (*os) { |
| 934 | if (*os == '\n' || *os == '\r') { |
| 935 | /* If newline is the last character, save it |
| 936 | * until next call to avoid bumping up the |
| 937 | * display output. |
| 938 | */ |
| 939 | if (*os == '\n' && !os[1]) { |
| 940 | pending_newline = 1; |
| 941 | current_line++; |
| 942 | if (current_line > display_lines-1) |
| 943 | current_line = display_lines-1; |
| 944 | spin_unlock(&progress_lock); |
| 945 | return; |
| 946 | } |
| 947 | |
| 948 | /* RTAS wants CR-LF, not just LF */ |
| 949 | |
| 950 | if (*os == '\n') { |
| 951 | rtas_call(display_character, 1, 1, NULL, '\r'); |
| 952 | rtas_call(display_character, 1, 1, NULL, '\n'); |
| 953 | } else { |
| 954 | /* CR might be used to re-draw a line, so we'll |
| 955 | * leave it alone and not add LF. |
| 956 | */ |
| 957 | rtas_call(display_character, 1, 1, NULL, *os); |
| 958 | } |
| 959 | |
| 960 | if (row_width) |
| 961 | width = row_width[current_line]; |
| 962 | else |
| 963 | width = display_width; |
| 964 | } else { |
| 965 | width--; |
| 966 | rtas_call(display_character, 1, 1, NULL, *os); |
| 967 | } |
| 968 | |
| 969 | os++; |
| 970 | |
| 971 | /* if we overwrite the screen length */ |
| 972 | if (width <= 0) |
| 973 | while ((*os != 0) && (*os != '\n') && (*os != '\r')) |
| 974 | os++; |
| 975 | } |
| 976 | |
| 977 | spin_unlock(&progress_lock); |
| 978 | } |
| 979 | EXPORT_SYMBOL_GPL(rtas_progress); /* needed by rtas_flash module */ |
| 980 | |
| 981 | int rtas_token(const char *service) |
| 982 | { |
| 983 | const struct rtas_function *func; |
| 984 | const __be32 *tokp; |
| 985 | |
| 986 | if (rtas.dev == NULL) |
| 987 | return RTAS_UNKNOWN_SERVICE; |
| 988 | |
| 989 | func = rtas_name_to_function(service); |
| 990 | if (func) |
| 991 | return func->token; |
| 992 | /* |
| 993 | * The caller is looking up a name that is not known to be an |
| 994 | * RTAS function. Either it's a function that needs to be |
| 995 | * added to the table, or they're misusing rtas_token() to |
| 996 | * access non-function properties of the /rtas node. Warn and |
| 997 | * fall back to the legacy behavior. |
| 998 | */ |
| 999 | WARN_ONCE(1, "unknown function `%s`, should it be added to rtas_function_table?\n", |
| 1000 | service); |
| 1001 | |
| 1002 | tokp = of_get_property(rtas.dev, service, NULL); |
| 1003 | return tokp ? be32_to_cpu(*tokp) : RTAS_UNKNOWN_SERVICE; |
| 1004 | } |
| 1005 | EXPORT_SYMBOL_GPL(rtas_token); |
| 1006 | |
| 1007 | #ifdef CONFIG_RTAS_ERROR_LOGGING |
| 1008 | |
| 1009 | static u32 rtas_error_log_max __ro_after_init = RTAS_ERROR_LOG_MAX; |
| 1010 | |
| 1011 | /* |
| 1012 | * Return the firmware-specified size of the error log buffer |
| 1013 | * for all rtas calls that require an error buffer argument. |
| 1014 | * This includes 'check-exception' and 'rtas-last-error'. |
| 1015 | */ |
| 1016 | int rtas_get_error_log_max(void) |
| 1017 | { |
| 1018 | return rtas_error_log_max; |
| 1019 | } |
| 1020 | |
| 1021 | static void __init init_error_log_max(void) |
| 1022 | { |
| 1023 | static const char propname[] __initconst = "rtas-error-log-max"; |
| 1024 | u32 max; |
| 1025 | |
| 1026 | if (of_property_read_u32(rtas.dev, propname, &max)) { |
| 1027 | pr_warn("%s not found, using default of %u\n", |
| 1028 | propname, RTAS_ERROR_LOG_MAX); |
| 1029 | max = RTAS_ERROR_LOG_MAX; |
| 1030 | } |
| 1031 | |
| 1032 | if (max > RTAS_ERROR_LOG_MAX) { |
| 1033 | pr_warn("%s = %u, clamping max error log size to %u\n", |
| 1034 | propname, max, RTAS_ERROR_LOG_MAX); |
| 1035 | max = RTAS_ERROR_LOG_MAX; |
| 1036 | } |
| 1037 | |
| 1038 | rtas_error_log_max = max; |
| 1039 | } |
| 1040 | |
| 1041 | |
| 1042 | static char rtas_err_buf[RTAS_ERROR_LOG_MAX]; |
| 1043 | |
| 1044 | /** Return a copy of the detailed error text associated with the |
| 1045 | * most recent failed call to rtas. Because the error text |
| 1046 | * might go stale if there are any other intervening rtas calls, |
| 1047 | * this routine must be called atomically with whatever produced |
| 1048 | * the error (i.e. with rtas_lock still held from the previous call). |
| 1049 | */ |
| 1050 | static char *__fetch_rtas_last_error(char *altbuf) |
| 1051 | { |
| 1052 | const s32 token = rtas_function_token(RTAS_FN_RTAS_LAST_ERROR); |
| 1053 | struct rtas_args err_args, save_args; |
| 1054 | u32 bufsz; |
| 1055 | char *buf = NULL; |
| 1056 | |
| 1057 | lockdep_assert_held(&rtas_lock); |
| 1058 | |
| 1059 | if (token == -1) |
| 1060 | return NULL; |
| 1061 | |
| 1062 | bufsz = rtas_get_error_log_max(); |
| 1063 | |
| 1064 | err_args.token = cpu_to_be32(token); |
| 1065 | err_args.nargs = cpu_to_be32(2); |
| 1066 | err_args.nret = cpu_to_be32(1); |
| 1067 | err_args.args[0] = cpu_to_be32(__pa(rtas_err_buf)); |
| 1068 | err_args.args[1] = cpu_to_be32(bufsz); |
| 1069 | err_args.args[2] = 0; |
| 1070 | |
| 1071 | save_args = rtas_args; |
| 1072 | rtas_args = err_args; |
| 1073 | |
| 1074 | do_enter_rtas(&rtas_args); |
| 1075 | |
| 1076 | err_args = rtas_args; |
| 1077 | rtas_args = save_args; |
| 1078 | |
| 1079 | /* Log the error in the unlikely case that there was one. */ |
| 1080 | if (unlikely(err_args.args[2] == 0)) { |
| 1081 | if (altbuf) { |
| 1082 | buf = altbuf; |
| 1083 | } else { |
| 1084 | buf = rtas_err_buf; |
| 1085 | if (slab_is_available()) |
| 1086 | buf = kmalloc(RTAS_ERROR_LOG_MAX, GFP_ATOMIC); |
| 1087 | } |
| 1088 | if (buf) |
| 1089 | memmove(buf, rtas_err_buf, RTAS_ERROR_LOG_MAX); |
| 1090 | } |
| 1091 | |
| 1092 | return buf; |
| 1093 | } |
| 1094 | |
| 1095 | #define get_errorlog_buffer() kmalloc(RTAS_ERROR_LOG_MAX, GFP_KERNEL) |
| 1096 | |
| 1097 | #else /* CONFIG_RTAS_ERROR_LOGGING */ |
| 1098 | #define __fetch_rtas_last_error(x) NULL |
| 1099 | #define get_errorlog_buffer() NULL |
| 1100 | static void __init init_error_log_max(void) {} |
| 1101 | #endif |
| 1102 | |
| 1103 | |
| 1104 | static void |
| 1105 | va_rtas_call_unlocked(struct rtas_args *args, int token, int nargs, int nret, |
| 1106 | va_list list) |
| 1107 | { |
| 1108 | int i; |
| 1109 | |
| 1110 | args->token = cpu_to_be32(token); |
| 1111 | args->nargs = cpu_to_be32(nargs); |
| 1112 | args->nret = cpu_to_be32(nret); |
| 1113 | args->rets = &(args->args[nargs]); |
| 1114 | |
| 1115 | for (i = 0; i < nargs; ++i) |
| 1116 | args->args[i] = cpu_to_be32(va_arg(list, __u32)); |
| 1117 | |
| 1118 | for (i = 0; i < nret; ++i) |
| 1119 | args->rets[i] = 0; |
| 1120 | |
| 1121 | do_enter_rtas(args); |
| 1122 | } |
| 1123 | |
| 1124 | /** |
| 1125 | * rtas_call_unlocked() - Invoke an RTAS firmware function without synchronization. |
| 1126 | * @args: RTAS parameter block to be used for the call, must obey RTAS addressing |
| 1127 | * constraints. |
| 1128 | * @token: Identifies the function being invoked. |
| 1129 | * @nargs: Number of input parameters. Does not include token. |
| 1130 | * @nret: Number of output parameters, including the call status. |
| 1131 | * @....: List of @nargs input parameters. |
| 1132 | * |
| 1133 | * Invokes the RTAS function indicated by @token, which the caller |
| 1134 | * should obtain via rtas_function_token(). |
| 1135 | * |
| 1136 | * This function is similar to rtas_call(), but must be used with a |
| 1137 | * limited set of RTAS calls specifically exempted from the general |
| 1138 | * requirement that only one RTAS call may be in progress at any |
| 1139 | * time. Examples include stop-self and ibm,nmi-interlock. |
| 1140 | */ |
| 1141 | void rtas_call_unlocked(struct rtas_args *args, int token, int nargs, int nret, ...) |
| 1142 | { |
| 1143 | va_list list; |
| 1144 | |
| 1145 | va_start(list, nret); |
| 1146 | va_rtas_call_unlocked(args, token, nargs, nret, list); |
| 1147 | va_end(list); |
| 1148 | } |
| 1149 | |
| 1150 | static bool token_is_restricted_errinjct(s32 token) |
| 1151 | { |
| 1152 | return token == rtas_function_token(RTAS_FN_IBM_OPEN_ERRINJCT) || |
| 1153 | token == rtas_function_token(RTAS_FN_IBM_ERRINJCT); |
| 1154 | } |
| 1155 | |
| 1156 | /** |
| 1157 | * rtas_call() - Invoke an RTAS firmware function. |
| 1158 | * @token: Identifies the function being invoked. |
| 1159 | * @nargs: Number of input parameters. Does not include token. |
| 1160 | * @nret: Number of output parameters, including the call status. |
| 1161 | * @outputs: Array of @nret output words. |
| 1162 | * @....: List of @nargs input parameters. |
| 1163 | * |
| 1164 | * Invokes the RTAS function indicated by @token, which the caller |
| 1165 | * should obtain via rtas_function_token(). |
| 1166 | * |
| 1167 | * The @nargs and @nret arguments must match the number of input and |
| 1168 | * output parameters specified for the RTAS function. |
| 1169 | * |
| 1170 | * rtas_call() returns RTAS status codes, not conventional Linux errno |
| 1171 | * values. Callers must translate any failure to an appropriate errno |
| 1172 | * in syscall context. Most callers of RTAS functions that can return |
| 1173 | * -2 or 990x should use rtas_busy_delay() to correctly handle those |
| 1174 | * statuses before calling again. |
| 1175 | * |
| 1176 | * The return value descriptions are adapted from 7.2.8 [RTAS] Return |
| 1177 | * Codes of the PAPR and CHRP specifications. |
| 1178 | * |
| 1179 | * Context: Process context preferably, interrupt context if |
| 1180 | * necessary. Acquires an internal spinlock and may perform |
| 1181 | * GFP_ATOMIC slab allocation in error path. Unsafe for NMI |
| 1182 | * context. |
| 1183 | * Return: |
| 1184 | * * 0 - RTAS function call succeeded. |
| 1185 | * * -1 - RTAS function encountered a hardware or |
| 1186 | * platform error, or the token is invalid, |
| 1187 | * or the function is restricted by kernel policy. |
| 1188 | * * -2 - Specs say "A necessary hardware device was busy, |
| 1189 | * and the requested function could not be |
| 1190 | * performed. The operation should be retried at |
| 1191 | * a later time." This is misleading, at least with |
| 1192 | * respect to current RTAS implementations. What it |
| 1193 | * usually means in practice is that the function |
| 1194 | * could not be completed while meeting RTAS's |
| 1195 | * deadline for returning control to the OS (250us |
| 1196 | * for PAPR/PowerVM, typically), but the call may be |
| 1197 | * immediately reattempted to resume work on it. |
| 1198 | * * -3 - Parameter error. |
| 1199 | * * -7 - Unexpected state change. |
| 1200 | * * 9000...9899 - Vendor-specific success codes. |
| 1201 | * * 9900...9905 - Advisory extended delay. Caller should try |
| 1202 | * again after ~10^x ms has elapsed, where x is |
| 1203 | * the last digit of the status [0-5]. Again going |
| 1204 | * beyond the PAPR text, 990x on PowerVM indicates |
| 1205 | * contention for RTAS-internal resources. Other |
| 1206 | * RTAS call sequences in progress should be |
| 1207 | * allowed to complete before reattempting the |
| 1208 | * call. |
| 1209 | * * -9000 - Multi-level isolation error. |
| 1210 | * * -9999...-9004 - Vendor-specific error codes. |
| 1211 | * * Additional negative values - Function-specific error. |
| 1212 | * * Additional positive values - Function-specific success. |
| 1213 | */ |
| 1214 | int rtas_call(int token, int nargs, int nret, int *outputs, ...) |
| 1215 | { |
| 1216 | struct pin_cookie cookie; |
| 1217 | va_list list; |
| 1218 | int i; |
| 1219 | unsigned long flags; |
| 1220 | struct rtas_args *args; |
| 1221 | char *buff_copy = NULL; |
| 1222 | int ret; |
| 1223 | |
| 1224 | if (!rtas.entry || token == RTAS_UNKNOWN_SERVICE) |
| 1225 | return -1; |
| 1226 | |
| 1227 | if (token_is_restricted_errinjct(token)) { |
| 1228 | /* |
| 1229 | * It would be nicer to not discard the error value |
| 1230 | * from security_locked_down(), but callers expect an |
| 1231 | * RTAS status, not an errno. |
| 1232 | */ |
| 1233 | if (security_locked_down(LOCKDOWN_RTAS_ERROR_INJECTION)) |
| 1234 | return -1; |
| 1235 | } |
| 1236 | |
| 1237 | if ((mfmsr() & (MSR_IR|MSR_DR)) != (MSR_IR|MSR_DR)) { |
| 1238 | WARN_ON_ONCE(1); |
| 1239 | return -1; |
| 1240 | } |
| 1241 | |
| 1242 | raw_spin_lock_irqsave(&rtas_lock, flags); |
| 1243 | cookie = lockdep_pin_lock(&rtas_lock); |
| 1244 | |
| 1245 | /* We use the global rtas args buffer */ |
| 1246 | args = &rtas_args; |
| 1247 | |
| 1248 | va_start(list, outputs); |
| 1249 | va_rtas_call_unlocked(args, token, nargs, nret, list); |
| 1250 | va_end(list); |
| 1251 | |
| 1252 | /* A -1 return code indicates that the last command couldn't |
| 1253 | be completed due to a hardware error. */ |
| 1254 | if (be32_to_cpu(args->rets[0]) == -1) |
| 1255 | buff_copy = __fetch_rtas_last_error(NULL); |
| 1256 | |
| 1257 | if (nret > 1 && outputs != NULL) |
| 1258 | for (i = 0; i < nret-1; ++i) |
| 1259 | outputs[i] = be32_to_cpu(args->rets[i + 1]); |
| 1260 | ret = (nret > 0) ? be32_to_cpu(args->rets[0]) : 0; |
| 1261 | |
| 1262 | lockdep_unpin_lock(&rtas_lock, cookie); |
| 1263 | raw_spin_unlock_irqrestore(&rtas_lock, flags); |
| 1264 | |
| 1265 | if (buff_copy) { |
| 1266 | log_error(buff_copy, ERR_TYPE_RTAS_LOG, 0); |
| 1267 | if (slab_is_available()) |
| 1268 | kfree(buff_copy); |
| 1269 | } |
| 1270 | return ret; |
| 1271 | } |
| 1272 | EXPORT_SYMBOL_GPL(rtas_call); |
| 1273 | |
| 1274 | /** |
| 1275 | * rtas_busy_delay_time() - From an RTAS status value, calculate the |
| 1276 | * suggested delay time in milliseconds. |
| 1277 | * |
| 1278 | * @status: a value returned from rtas_call() or similar APIs which return |
| 1279 | * the status of a RTAS function call. |
| 1280 | * |
| 1281 | * Context: Any context. |
| 1282 | * |
| 1283 | * Return: |
| 1284 | * * 100000 - If @status is 9905. |
| 1285 | * * 10000 - If @status is 9904. |
| 1286 | * * 1000 - If @status is 9903. |
| 1287 | * * 100 - If @status is 9902. |
| 1288 | * * 10 - If @status is 9901. |
| 1289 | * * 1 - If @status is either 9900 or -2. This is "wrong" for -2, but |
| 1290 | * some callers depend on this behavior, and the worst outcome |
| 1291 | * is that they will delay for longer than necessary. |
| 1292 | * * 0 - If @status is not a busy or extended delay value. |
| 1293 | */ |
| 1294 | unsigned int rtas_busy_delay_time(int status) |
| 1295 | { |
| 1296 | int order; |
| 1297 | unsigned int ms = 0; |
| 1298 | |
| 1299 | if (status == RTAS_BUSY) { |
| 1300 | ms = 1; |
| 1301 | } else if (status >= RTAS_EXTENDED_DELAY_MIN && |
| 1302 | status <= RTAS_EXTENDED_DELAY_MAX) { |
| 1303 | order = status - RTAS_EXTENDED_DELAY_MIN; |
| 1304 | for (ms = 1; order > 0; order--) |
| 1305 | ms *= 10; |
| 1306 | } |
| 1307 | |
| 1308 | return ms; |
| 1309 | } |
| 1310 | |
| 1311 | /* |
| 1312 | * Early boot fallback for rtas_busy_delay(). |
| 1313 | */ |
| 1314 | static bool __init rtas_busy_delay_early(int status) |
| 1315 | { |
| 1316 | static size_t successive_ext_delays __initdata; |
| 1317 | bool retry; |
| 1318 | |
| 1319 | switch (status) { |
| 1320 | case RTAS_EXTENDED_DELAY_MIN...RTAS_EXTENDED_DELAY_MAX: |
| 1321 | /* |
| 1322 | * In the unlikely case that we receive an extended |
| 1323 | * delay status in early boot, the OS is probably not |
| 1324 | * the cause, and there's nothing we can do to clear |
| 1325 | * the condition. Best we can do is delay for a bit |
| 1326 | * and hope it's transient. Lie to the caller if it |
| 1327 | * seems like we're stuck in a retry loop. |
| 1328 | */ |
| 1329 | mdelay(1); |
| 1330 | retry = true; |
| 1331 | successive_ext_delays += 1; |
| 1332 | if (successive_ext_delays > 1000) { |
| 1333 | pr_err("too many extended delays, giving up\n"); |
| 1334 | dump_stack(); |
| 1335 | retry = false; |
| 1336 | successive_ext_delays = 0; |
| 1337 | } |
| 1338 | break; |
| 1339 | case RTAS_BUSY: |
| 1340 | retry = true; |
| 1341 | successive_ext_delays = 0; |
| 1342 | break; |
| 1343 | default: |
| 1344 | retry = false; |
| 1345 | successive_ext_delays = 0; |
| 1346 | break; |
| 1347 | } |
| 1348 | |
| 1349 | return retry; |
| 1350 | } |
| 1351 | |
| 1352 | /** |
| 1353 | * rtas_busy_delay() - helper for RTAS busy and extended delay statuses |
| 1354 | * |
| 1355 | * @status: a value returned from rtas_call() or similar APIs which return |
| 1356 | * the status of a RTAS function call. |
| 1357 | * |
| 1358 | * Context: Process context. May sleep or schedule. |
| 1359 | * |
| 1360 | * Return: |
| 1361 | * * true - @status is RTAS_BUSY or an extended delay hint. The |
| 1362 | * caller may assume that the CPU has been yielded if necessary, |
| 1363 | * and that an appropriate delay for @status has elapsed. |
| 1364 | * Generally the caller should reattempt the RTAS call which |
| 1365 | * yielded @status. |
| 1366 | * |
| 1367 | * * false - @status is not @RTAS_BUSY nor an extended delay hint. The |
| 1368 | * caller is responsible for handling @status. |
| 1369 | */ |
| 1370 | bool __ref rtas_busy_delay(int status) |
| 1371 | { |
| 1372 | unsigned int ms; |
| 1373 | bool ret; |
| 1374 | |
| 1375 | /* |
| 1376 | * Can't do timed sleeps before timekeeping is up. |
| 1377 | */ |
| 1378 | if (system_state < SYSTEM_SCHEDULING) |
| 1379 | return rtas_busy_delay_early(status); |
| 1380 | |
| 1381 | switch (status) { |
| 1382 | case RTAS_EXTENDED_DELAY_MIN...RTAS_EXTENDED_DELAY_MAX: |
| 1383 | ret = true; |
| 1384 | ms = rtas_busy_delay_time(status); |
| 1385 | /* |
| 1386 | * The extended delay hint can be as high as 100 seconds. |
| 1387 | * Surely any function returning such a status is either |
| 1388 | * buggy or isn't going to be significantly slowed by us |
| 1389 | * polling at 1HZ. Clamp the sleep time to one second. |
| 1390 | */ |
| 1391 | ms = clamp(ms, 1U, 1000U); |
| 1392 | /* |
| 1393 | * The delay hint is an order-of-magnitude suggestion, not |
| 1394 | * a minimum. It is fine, possibly even advantageous, for |
| 1395 | * us to pause for less time than hinted. For small values, |
| 1396 | * use usleep_range() to ensure we don't sleep much longer |
| 1397 | * than actually needed. |
| 1398 | * |
| 1399 | * See Documentation/timers/timers-howto.rst for |
| 1400 | * explanation of the threshold used here. In effect we use |
| 1401 | * usleep_range() for 9900 and 9901, msleep() for |
| 1402 | * 9902-9905. |
| 1403 | */ |
| 1404 | if (ms <= 20) |
| 1405 | usleep_range(ms * 100, ms * 1000); |
| 1406 | else |
| 1407 | msleep(ms); |
| 1408 | break; |
| 1409 | case RTAS_BUSY: |
| 1410 | ret = true; |
| 1411 | /* |
| 1412 | * We should call again immediately if there's no other |
| 1413 | * work to do. |
| 1414 | */ |
| 1415 | cond_resched(); |
| 1416 | break; |
| 1417 | default: |
| 1418 | ret = false; |
| 1419 | /* |
| 1420 | * Not a busy or extended delay status; the caller should |
| 1421 | * handle @status itself. Ensure we warn on misuses in |
| 1422 | * atomic context regardless. |
| 1423 | */ |
| 1424 | might_sleep(); |
| 1425 | break; |
| 1426 | } |
| 1427 | |
| 1428 | return ret; |
| 1429 | } |
| 1430 | EXPORT_SYMBOL_GPL(rtas_busy_delay); |
| 1431 | |
| 1432 | int rtas_error_rc(int rtas_rc) |
| 1433 | { |
| 1434 | int rc; |
| 1435 | |
| 1436 | switch (rtas_rc) { |
| 1437 | case RTAS_HARDWARE_ERROR: /* Hardware Error */ |
| 1438 | rc = -EIO; |
| 1439 | break; |
| 1440 | case RTAS_INVALID_PARAMETER: /* Bad indicator/domain/etc */ |
| 1441 | rc = -EINVAL; |
| 1442 | break; |
| 1443 | case -9000: /* Isolation error */ |
| 1444 | rc = -EFAULT; |
| 1445 | break; |
| 1446 | case -9001: /* Outstanding TCE/PTE */ |
| 1447 | rc = -EEXIST; |
| 1448 | break; |
| 1449 | case -9002: /* No usable slot */ |
| 1450 | rc = -ENODEV; |
| 1451 | break; |
| 1452 | default: |
| 1453 | pr_err("%s: unexpected error %d\n", __func__, rtas_rc); |
| 1454 | rc = -ERANGE; |
| 1455 | break; |
| 1456 | } |
| 1457 | return rc; |
| 1458 | } |
| 1459 | EXPORT_SYMBOL_GPL(rtas_error_rc); |
| 1460 | |
| 1461 | int rtas_get_power_level(int powerdomain, int *level) |
| 1462 | { |
| 1463 | int token = rtas_function_token(RTAS_FN_GET_POWER_LEVEL); |
| 1464 | int rc; |
| 1465 | |
| 1466 | if (token == RTAS_UNKNOWN_SERVICE) |
| 1467 | return -ENOENT; |
| 1468 | |
| 1469 | while ((rc = rtas_call(token, 1, 2, level, powerdomain)) == RTAS_BUSY) |
| 1470 | udelay(1); |
| 1471 | |
| 1472 | if (rc < 0) |
| 1473 | return rtas_error_rc(rc); |
| 1474 | return rc; |
| 1475 | } |
| 1476 | EXPORT_SYMBOL_GPL(rtas_get_power_level); |
| 1477 | |
| 1478 | int rtas_set_power_level(int powerdomain, int level, int *setlevel) |
| 1479 | { |
| 1480 | int token = rtas_function_token(RTAS_FN_SET_POWER_LEVEL); |
| 1481 | int rc; |
| 1482 | |
| 1483 | if (token == RTAS_UNKNOWN_SERVICE) |
| 1484 | return -ENOENT; |
| 1485 | |
| 1486 | do { |
| 1487 | rc = rtas_call(token, 2, 2, setlevel, powerdomain, level); |
| 1488 | } while (rtas_busy_delay(rc)); |
| 1489 | |
| 1490 | if (rc < 0) |
| 1491 | return rtas_error_rc(rc); |
| 1492 | return rc; |
| 1493 | } |
| 1494 | EXPORT_SYMBOL_GPL(rtas_set_power_level); |
| 1495 | |
| 1496 | int rtas_get_sensor(int sensor, int index, int *state) |
| 1497 | { |
| 1498 | int token = rtas_function_token(RTAS_FN_GET_SENSOR_STATE); |
| 1499 | int rc; |
| 1500 | |
| 1501 | if (token == RTAS_UNKNOWN_SERVICE) |
| 1502 | return -ENOENT; |
| 1503 | |
| 1504 | do { |
| 1505 | rc = rtas_call(token, 2, 2, state, sensor, index); |
| 1506 | } while (rtas_busy_delay(rc)); |
| 1507 | |
| 1508 | if (rc < 0) |
| 1509 | return rtas_error_rc(rc); |
| 1510 | return rc; |
| 1511 | } |
| 1512 | EXPORT_SYMBOL_GPL(rtas_get_sensor); |
| 1513 | |
| 1514 | int rtas_get_sensor_fast(int sensor, int index, int *state) |
| 1515 | { |
| 1516 | int token = rtas_function_token(RTAS_FN_GET_SENSOR_STATE); |
| 1517 | int rc; |
| 1518 | |
| 1519 | if (token == RTAS_UNKNOWN_SERVICE) |
| 1520 | return -ENOENT; |
| 1521 | |
| 1522 | rc = rtas_call(token, 2, 2, state, sensor, index); |
| 1523 | WARN_ON(rc == RTAS_BUSY || (rc >= RTAS_EXTENDED_DELAY_MIN && |
| 1524 | rc <= RTAS_EXTENDED_DELAY_MAX)); |
| 1525 | |
| 1526 | if (rc < 0) |
| 1527 | return rtas_error_rc(rc); |
| 1528 | return rc; |
| 1529 | } |
| 1530 | |
| 1531 | bool rtas_indicator_present(int token, int *maxindex) |
| 1532 | { |
| 1533 | int proplen, count, i; |
| 1534 | const struct indicator_elem { |
| 1535 | __be32 token; |
| 1536 | __be32 maxindex; |
| 1537 | } *indicators; |
| 1538 | |
| 1539 | indicators = of_get_property(rtas.dev, "rtas-indicators", &proplen); |
| 1540 | if (!indicators) |
| 1541 | return false; |
| 1542 | |
| 1543 | count = proplen / sizeof(struct indicator_elem); |
| 1544 | |
| 1545 | for (i = 0; i < count; i++) { |
| 1546 | if (__be32_to_cpu(indicators[i].token) != token) |
| 1547 | continue; |
| 1548 | if (maxindex) |
| 1549 | *maxindex = __be32_to_cpu(indicators[i].maxindex); |
| 1550 | return true; |
| 1551 | } |
| 1552 | |
| 1553 | return false; |
| 1554 | } |
| 1555 | |
| 1556 | int rtas_set_indicator(int indicator, int index, int new_value) |
| 1557 | { |
| 1558 | int token = rtas_function_token(RTAS_FN_SET_INDICATOR); |
| 1559 | int rc; |
| 1560 | |
| 1561 | if (token == RTAS_UNKNOWN_SERVICE) |
| 1562 | return -ENOENT; |
| 1563 | |
| 1564 | do { |
| 1565 | rc = rtas_call(token, 3, 1, NULL, indicator, index, new_value); |
| 1566 | } while (rtas_busy_delay(rc)); |
| 1567 | |
| 1568 | if (rc < 0) |
| 1569 | return rtas_error_rc(rc); |
| 1570 | return rc; |
| 1571 | } |
| 1572 | EXPORT_SYMBOL_GPL(rtas_set_indicator); |
| 1573 | |
| 1574 | /* |
| 1575 | * Ignoring RTAS extended delay |
| 1576 | */ |
| 1577 | int rtas_set_indicator_fast(int indicator, int index, int new_value) |
| 1578 | { |
| 1579 | int token = rtas_function_token(RTAS_FN_SET_INDICATOR); |
| 1580 | int rc; |
| 1581 | |
| 1582 | if (token == RTAS_UNKNOWN_SERVICE) |
| 1583 | return -ENOENT; |
| 1584 | |
| 1585 | rc = rtas_call(token, 3, 1, NULL, indicator, index, new_value); |
| 1586 | |
| 1587 | WARN_ON(rc == RTAS_BUSY || (rc >= RTAS_EXTENDED_DELAY_MIN && |
| 1588 | rc <= RTAS_EXTENDED_DELAY_MAX)); |
| 1589 | |
| 1590 | if (rc < 0) |
| 1591 | return rtas_error_rc(rc); |
| 1592 | |
| 1593 | return rc; |
| 1594 | } |
| 1595 | |
| 1596 | /** |
| 1597 | * rtas_ibm_suspend_me() - Call ibm,suspend-me to suspend the LPAR. |
| 1598 | * |
| 1599 | * @fw_status: RTAS call status will be placed here if not NULL. |
| 1600 | * |
| 1601 | * rtas_ibm_suspend_me() should be called only on a CPU which has |
| 1602 | * received H_CONTINUE from the H_JOIN hcall. All other active CPUs |
| 1603 | * should be waiting to return from H_JOIN. |
| 1604 | * |
| 1605 | * rtas_ibm_suspend_me() may suspend execution of the OS |
| 1606 | * indefinitely. Callers should take appropriate measures upon return, such as |
| 1607 | * resetting watchdog facilities. |
| 1608 | * |
| 1609 | * Callers may choose to retry this call if @fw_status is |
| 1610 | * %RTAS_THREADS_ACTIVE. |
| 1611 | * |
| 1612 | * Return: |
| 1613 | * 0 - The partition has resumed from suspend, possibly after |
| 1614 | * migration to a different host. |
| 1615 | * -ECANCELED - The operation was aborted. |
| 1616 | * -EAGAIN - There were other CPUs not in H_JOIN at the time of the call. |
| 1617 | * -EBUSY - Some other condition prevented the suspend from succeeding. |
| 1618 | * -EIO - Hardware/platform error. |
| 1619 | */ |
| 1620 | int rtas_ibm_suspend_me(int *fw_status) |
| 1621 | { |
| 1622 | int token = rtas_function_token(RTAS_FN_IBM_SUSPEND_ME); |
| 1623 | int fwrc; |
| 1624 | int ret; |
| 1625 | |
| 1626 | fwrc = rtas_call(token, 0, 1, NULL); |
| 1627 | |
| 1628 | switch (fwrc) { |
| 1629 | case 0: |
| 1630 | ret = 0; |
| 1631 | break; |
| 1632 | case RTAS_SUSPEND_ABORTED: |
| 1633 | ret = -ECANCELED; |
| 1634 | break; |
| 1635 | case RTAS_THREADS_ACTIVE: |
| 1636 | ret = -EAGAIN; |
| 1637 | break; |
| 1638 | case RTAS_NOT_SUSPENDABLE: |
| 1639 | case RTAS_OUTSTANDING_COPROC: |
| 1640 | ret = -EBUSY; |
| 1641 | break; |
| 1642 | case -1: |
| 1643 | default: |
| 1644 | ret = -EIO; |
| 1645 | break; |
| 1646 | } |
| 1647 | |
| 1648 | if (fw_status) |
| 1649 | *fw_status = fwrc; |
| 1650 | |
| 1651 | return ret; |
| 1652 | } |
| 1653 | |
| 1654 | void __noreturn rtas_restart(char *cmd) |
| 1655 | { |
| 1656 | if (rtas_flash_term_hook) |
| 1657 | rtas_flash_term_hook(SYS_RESTART); |
| 1658 | pr_emerg("system-reboot returned %d\n", |
| 1659 | rtas_call(rtas_function_token(RTAS_FN_SYSTEM_REBOOT), 0, 1, NULL)); |
| 1660 | for (;;); |
| 1661 | } |
| 1662 | |
| 1663 | void rtas_power_off(void) |
| 1664 | { |
| 1665 | if (rtas_flash_term_hook) |
| 1666 | rtas_flash_term_hook(SYS_POWER_OFF); |
| 1667 | /* allow power on only with power button press */ |
| 1668 | pr_emerg("power-off returned %d\n", |
| 1669 | rtas_call(rtas_function_token(RTAS_FN_POWER_OFF), 2, 1, NULL, -1, -1)); |
| 1670 | for (;;); |
| 1671 | } |
| 1672 | |
| 1673 | void __noreturn rtas_halt(void) |
| 1674 | { |
| 1675 | if (rtas_flash_term_hook) |
| 1676 | rtas_flash_term_hook(SYS_HALT); |
| 1677 | /* allow power on only with power button press */ |
| 1678 | pr_emerg("power-off returned %d\n", |
| 1679 | rtas_call(rtas_function_token(RTAS_FN_POWER_OFF), 2, 1, NULL, -1, -1)); |
| 1680 | for (;;); |
| 1681 | } |
| 1682 | |
| 1683 | /* Must be in the RMO region, so we place it here */ |
| 1684 | static char rtas_os_term_buf[2048]; |
| 1685 | static bool ibm_extended_os_term; |
| 1686 | |
| 1687 | void rtas_os_term(char *str) |
| 1688 | { |
| 1689 | s32 token = rtas_function_token(RTAS_FN_IBM_OS_TERM); |
| 1690 | static struct rtas_args args; |
| 1691 | int status; |
| 1692 | |
| 1693 | /* |
| 1694 | * Firmware with the ibm,extended-os-term property is guaranteed |
| 1695 | * to always return from an ibm,os-term call. Earlier versions without |
| 1696 | * this property may terminate the partition which we want to avoid |
| 1697 | * since it interferes with panic_timeout. |
| 1698 | */ |
| 1699 | |
| 1700 | if (token == RTAS_UNKNOWN_SERVICE || !ibm_extended_os_term) |
| 1701 | return; |
| 1702 | |
| 1703 | snprintf(rtas_os_term_buf, 2048, "OS panic: %s", str); |
| 1704 | |
| 1705 | /* |
| 1706 | * Keep calling as long as RTAS returns a "try again" status, |
| 1707 | * but don't use rtas_busy_delay(), which potentially |
| 1708 | * schedules. |
| 1709 | */ |
| 1710 | do { |
| 1711 | rtas_call_unlocked(&args, token, 1, 1, NULL, __pa(rtas_os_term_buf)); |
| 1712 | status = be32_to_cpu(args.rets[0]); |
| 1713 | } while (rtas_busy_delay_time(status)); |
| 1714 | |
| 1715 | if (status != 0) |
| 1716 | pr_emerg("ibm,os-term call failed %d\n", status); |
| 1717 | } |
| 1718 | |
| 1719 | /** |
| 1720 | * rtas_activate_firmware() - Activate a new version of firmware. |
| 1721 | * |
| 1722 | * Context: This function may sleep. |
| 1723 | * |
| 1724 | * Activate a new version of partition firmware. The OS must call this |
| 1725 | * after resuming from a partition hibernation or migration in order |
| 1726 | * to maintain the ability to perform live firmware updates. It's not |
| 1727 | * catastrophic for this method to be absent or to fail; just log the |
| 1728 | * condition in that case. |
| 1729 | */ |
| 1730 | void rtas_activate_firmware(void) |
| 1731 | { |
| 1732 | int token = rtas_function_token(RTAS_FN_IBM_ACTIVATE_FIRMWARE); |
| 1733 | int fwrc; |
| 1734 | |
| 1735 | if (token == RTAS_UNKNOWN_SERVICE) { |
| 1736 | pr_notice("ibm,activate-firmware method unavailable\n"); |
| 1737 | return; |
| 1738 | } |
| 1739 | |
| 1740 | mutex_lock(&rtas_ibm_activate_firmware_lock); |
| 1741 | |
| 1742 | do { |
| 1743 | fwrc = rtas_call(token, 0, 1, NULL); |
| 1744 | } while (rtas_busy_delay(fwrc)); |
| 1745 | |
| 1746 | mutex_unlock(&rtas_ibm_activate_firmware_lock); |
| 1747 | |
| 1748 | if (fwrc) |
| 1749 | pr_err("ibm,activate-firmware failed (%i)\n", fwrc); |
| 1750 | } |
| 1751 | |
| 1752 | /** |
| 1753 | * get_pseries_errorlog() - Find a specific pseries error log in an RTAS |
| 1754 | * extended event log. |
| 1755 | * @log: RTAS error/event log |
| 1756 | * @section_id: two character section identifier |
| 1757 | * |
| 1758 | * Return: A pointer to the specified errorlog or NULL if not found. |
| 1759 | */ |
| 1760 | noinstr struct pseries_errorlog *get_pseries_errorlog(struct rtas_error_log *log, |
| 1761 | uint16_t section_id) |
| 1762 | { |
| 1763 | struct rtas_ext_event_log_v6 *ext_log = |
| 1764 | (struct rtas_ext_event_log_v6 *)log->buffer; |
| 1765 | struct pseries_errorlog *sect; |
| 1766 | unsigned char *p, *log_end; |
| 1767 | uint32_t ext_log_length = rtas_error_extended_log_length(log); |
| 1768 | uint8_t log_format = rtas_ext_event_log_format(ext_log); |
| 1769 | uint32_t company_id = rtas_ext_event_company_id(ext_log); |
| 1770 | |
| 1771 | /* Check that we understand the format */ |
| 1772 | if (ext_log_length < sizeof(struct rtas_ext_event_log_v6) || |
| 1773 | log_format != RTAS_V6EXT_LOG_FORMAT_EVENT_LOG || |
| 1774 | company_id != RTAS_V6EXT_COMPANY_ID_IBM) |
| 1775 | return NULL; |
| 1776 | |
| 1777 | log_end = log->buffer + ext_log_length; |
| 1778 | p = ext_log->vendor_log; |
| 1779 | |
| 1780 | while (p < log_end) { |
| 1781 | sect = (struct pseries_errorlog *)p; |
| 1782 | if (pseries_errorlog_id(sect) == section_id) |
| 1783 | return sect; |
| 1784 | p += pseries_errorlog_length(sect); |
| 1785 | } |
| 1786 | |
| 1787 | return NULL; |
| 1788 | } |
| 1789 | |
| 1790 | /* |
| 1791 | * The sys_rtas syscall, as originally designed, allows root to pass |
| 1792 | * arbitrary physical addresses to RTAS calls. A number of RTAS calls |
| 1793 | * can be abused to write to arbitrary memory and do other things that |
| 1794 | * are potentially harmful to system integrity, and thus should only |
| 1795 | * be used inside the kernel and not exposed to userspace. |
| 1796 | * |
| 1797 | * All known legitimate users of the sys_rtas syscall will only ever |
| 1798 | * pass addresses that fall within the RMO buffer, and use a known |
| 1799 | * subset of RTAS calls. |
| 1800 | * |
| 1801 | * Accordingly, we filter RTAS requests to check that the call is |
| 1802 | * permitted, and that provided pointers fall within the RMO buffer. |
| 1803 | * If a function is allowed to be invoked via the syscall, then its |
| 1804 | * entry in the rtas_functions table points to a rtas_filter that |
| 1805 | * describes its constraints, with the indexes of the parameters which |
| 1806 | * are expected to contain addresses and sizes of buffers allocated |
| 1807 | * inside the RMO buffer. |
| 1808 | */ |
| 1809 | |
| 1810 | static bool in_rmo_buf(u32 base, u32 end) |
| 1811 | { |
| 1812 | return base >= rtas_rmo_buf && |
| 1813 | base < (rtas_rmo_buf + RTAS_USER_REGION_SIZE) && |
| 1814 | base <= end && |
| 1815 | end >= rtas_rmo_buf && |
| 1816 | end < (rtas_rmo_buf + RTAS_USER_REGION_SIZE); |
| 1817 | } |
| 1818 | |
| 1819 | static bool block_rtas_call(const struct rtas_function *func, int nargs, |
| 1820 | struct rtas_args *args) |
| 1821 | { |
| 1822 | const struct rtas_filter *f; |
| 1823 | const bool is_platform_dump = |
| 1824 | func == &rtas_function_table[RTAS_FNIDX__IBM_PLATFORM_DUMP]; |
| 1825 | const bool is_config_conn = |
| 1826 | func == &rtas_function_table[RTAS_FNIDX__IBM_CONFIGURE_CONNECTOR]; |
| 1827 | u32 base, size, end; |
| 1828 | |
| 1829 | /* |
| 1830 | * Only functions with filters attached are allowed. |
| 1831 | */ |
| 1832 | f = func->filter; |
| 1833 | if (!f) |
| 1834 | goto err; |
| 1835 | /* |
| 1836 | * And some functions aren't allowed on LE. |
| 1837 | */ |
| 1838 | if (IS_ENABLED(CONFIG_CPU_LITTLE_ENDIAN) && func->banned_for_syscall_on_le) |
| 1839 | goto err; |
| 1840 | |
| 1841 | if (f->buf_idx1 != -1) { |
| 1842 | base = be32_to_cpu(args->args[f->buf_idx1]); |
| 1843 | if (f->size_idx1 != -1) |
| 1844 | size = be32_to_cpu(args->args[f->size_idx1]); |
| 1845 | else if (f->fixed_size) |
| 1846 | size = f->fixed_size; |
| 1847 | else |
| 1848 | size = 1; |
| 1849 | |
| 1850 | end = base + size - 1; |
| 1851 | |
| 1852 | /* |
| 1853 | * Special case for ibm,platform-dump - NULL buffer |
| 1854 | * address is used to indicate end of dump processing |
| 1855 | */ |
| 1856 | if (is_platform_dump && base == 0) |
| 1857 | return false; |
| 1858 | |
| 1859 | if (!in_rmo_buf(base, end)) |
| 1860 | goto err; |
| 1861 | } |
| 1862 | |
| 1863 | if (f->buf_idx2 != -1) { |
| 1864 | base = be32_to_cpu(args->args[f->buf_idx2]); |
| 1865 | if (f->size_idx2 != -1) |
| 1866 | size = be32_to_cpu(args->args[f->size_idx2]); |
| 1867 | else if (f->fixed_size) |
| 1868 | size = f->fixed_size; |
| 1869 | else |
| 1870 | size = 1; |
| 1871 | end = base + size - 1; |
| 1872 | |
| 1873 | /* |
| 1874 | * Special case for ibm,configure-connector where the |
| 1875 | * address can be 0 |
| 1876 | */ |
| 1877 | if (is_config_conn && base == 0) |
| 1878 | return false; |
| 1879 | |
| 1880 | if (!in_rmo_buf(base, end)) |
| 1881 | goto err; |
| 1882 | } |
| 1883 | |
| 1884 | return false; |
| 1885 | err: |
| 1886 | pr_err_ratelimited("sys_rtas: RTAS call blocked - exploit attempt?\n"); |
| 1887 | pr_err_ratelimited("sys_rtas: %s nargs=%d (called by %s)\n", |
| 1888 | func->name, nargs, current->comm); |
| 1889 | return true; |
| 1890 | } |
| 1891 | |
| 1892 | /* We assume to be passed big endian arguments */ |
| 1893 | SYSCALL_DEFINE1(rtas, struct rtas_args __user *, uargs) |
| 1894 | { |
| 1895 | const struct rtas_function *func; |
| 1896 | struct pin_cookie cookie; |
| 1897 | struct rtas_args args; |
| 1898 | unsigned long flags; |
| 1899 | char *buff_copy, *errbuf = NULL; |
| 1900 | int nargs, nret, token; |
| 1901 | |
| 1902 | if (!capable(CAP_SYS_ADMIN)) |
| 1903 | return -EPERM; |
| 1904 | |
| 1905 | if (!rtas.entry) |
| 1906 | return -EINVAL; |
| 1907 | |
| 1908 | if (copy_from_user(&args, uargs, 3 * sizeof(u32)) != 0) |
| 1909 | return -EFAULT; |
| 1910 | |
| 1911 | nargs = be32_to_cpu(args.nargs); |
| 1912 | nret = be32_to_cpu(args.nret); |
| 1913 | token = be32_to_cpu(args.token); |
| 1914 | |
| 1915 | if (nargs >= ARRAY_SIZE(args.args) |
| 1916 | || nret > ARRAY_SIZE(args.args) |
| 1917 | || nargs + nret > ARRAY_SIZE(args.args)) |
| 1918 | return -EINVAL; |
| 1919 | |
| 1920 | nargs = array_index_nospec(nargs, ARRAY_SIZE(args.args)); |
| 1921 | nret = array_index_nospec(nret, ARRAY_SIZE(args.args) - nargs); |
| 1922 | |
| 1923 | /* Copy in args. */ |
| 1924 | if (copy_from_user(args.args, uargs->args, |
| 1925 | nargs * sizeof(rtas_arg_t)) != 0) |
| 1926 | return -EFAULT; |
| 1927 | |
| 1928 | /* |
| 1929 | * If this token doesn't correspond to a function the kernel |
| 1930 | * understands, you're not allowed to call it. |
| 1931 | */ |
| 1932 | func = rtas_token_to_function_untrusted(token); |
| 1933 | if (!func) |
| 1934 | return -EINVAL; |
| 1935 | |
| 1936 | args.rets = &args.args[nargs]; |
| 1937 | memset(args.rets, 0, nret * sizeof(rtas_arg_t)); |
| 1938 | |
| 1939 | if (block_rtas_call(func, nargs, &args)) |
| 1940 | return -EINVAL; |
| 1941 | |
| 1942 | if (token_is_restricted_errinjct(token)) { |
| 1943 | int err; |
| 1944 | |
| 1945 | err = security_locked_down(LOCKDOWN_RTAS_ERROR_INJECTION); |
| 1946 | if (err) |
| 1947 | return err; |
| 1948 | } |
| 1949 | |
| 1950 | /* Need to handle ibm,suspend_me call specially */ |
| 1951 | if (token == rtas_function_token(RTAS_FN_IBM_SUSPEND_ME)) { |
| 1952 | |
| 1953 | /* |
| 1954 | * rtas_ibm_suspend_me assumes the streamid handle is in cpu |
| 1955 | * endian, or at least the hcall within it requires it. |
| 1956 | */ |
| 1957 | int rc = 0; |
| 1958 | u64 handle = ((u64)be32_to_cpu(args.args[0]) << 32) |
| 1959 | | be32_to_cpu(args.args[1]); |
| 1960 | rc = rtas_syscall_dispatch_ibm_suspend_me(handle); |
| 1961 | if (rc == -EAGAIN) |
| 1962 | args.rets[0] = cpu_to_be32(RTAS_NOT_SUSPENDABLE); |
| 1963 | else if (rc == -EIO) |
| 1964 | args.rets[0] = cpu_to_be32(-1); |
| 1965 | else if (rc) |
| 1966 | return rc; |
| 1967 | goto copy_return; |
| 1968 | } |
| 1969 | |
| 1970 | buff_copy = get_errorlog_buffer(); |
| 1971 | |
| 1972 | /* |
| 1973 | * If this function has a mutex assigned to it, we must |
| 1974 | * acquire it to avoid interleaving with any kernel-based uses |
| 1975 | * of the same function. Kernel-based sequences acquire the |
| 1976 | * appropriate mutex explicitly. |
| 1977 | */ |
| 1978 | if (func->lock) |
| 1979 | mutex_lock(func->lock); |
| 1980 | |
| 1981 | raw_spin_lock_irqsave(&rtas_lock, flags); |
| 1982 | cookie = lockdep_pin_lock(&rtas_lock); |
| 1983 | |
| 1984 | rtas_args = args; |
| 1985 | do_enter_rtas(&rtas_args); |
| 1986 | args = rtas_args; |
| 1987 | |
| 1988 | /* A -1 return code indicates that the last command couldn't |
| 1989 | be completed due to a hardware error. */ |
| 1990 | if (be32_to_cpu(args.rets[0]) == -1) |
| 1991 | errbuf = __fetch_rtas_last_error(buff_copy); |
| 1992 | |
| 1993 | lockdep_unpin_lock(&rtas_lock, cookie); |
| 1994 | raw_spin_unlock_irqrestore(&rtas_lock, flags); |
| 1995 | |
| 1996 | if (func->lock) |
| 1997 | mutex_unlock(func->lock); |
| 1998 | |
| 1999 | if (buff_copy) { |
| 2000 | if (errbuf) |
| 2001 | log_error(errbuf, ERR_TYPE_RTAS_LOG, 0); |
| 2002 | kfree(buff_copy); |
| 2003 | } |
| 2004 | |
| 2005 | copy_return: |
| 2006 | /* Copy out args. */ |
| 2007 | if (copy_to_user(uargs->args + nargs, |
| 2008 | args.args + nargs, |
| 2009 | nret * sizeof(rtas_arg_t)) != 0) |
| 2010 | return -EFAULT; |
| 2011 | |
| 2012 | return 0; |
| 2013 | } |
| 2014 | |
| 2015 | static void __init rtas_function_table_init(void) |
| 2016 | { |
| 2017 | struct property *prop; |
| 2018 | |
| 2019 | for (size_t i = 0; i < ARRAY_SIZE(rtas_function_table); ++i) { |
| 2020 | struct rtas_function *curr = &rtas_function_table[i]; |
| 2021 | struct rtas_function *prior; |
| 2022 | int cmp; |
| 2023 | |
| 2024 | curr->token = RTAS_UNKNOWN_SERVICE; |
| 2025 | |
| 2026 | if (i == 0) |
| 2027 | continue; |
| 2028 | /* |
| 2029 | * Ensure table is sorted correctly for binary search |
| 2030 | * on function names. |
| 2031 | */ |
| 2032 | prior = &rtas_function_table[i - 1]; |
| 2033 | |
| 2034 | cmp = strcmp(prior->name, curr->name); |
| 2035 | if (cmp < 0) |
| 2036 | continue; |
| 2037 | |
| 2038 | if (cmp == 0) { |
| 2039 | pr_err("'%s' has duplicate function table entries\n", |
| 2040 | curr->name); |
| 2041 | } else { |
| 2042 | pr_err("function table unsorted: '%s' wrongly precedes '%s'\n", |
| 2043 | prior->name, curr->name); |
| 2044 | } |
| 2045 | } |
| 2046 | |
| 2047 | for_each_property_of_node(rtas.dev, prop) { |
| 2048 | struct rtas_function *func; |
| 2049 | |
| 2050 | if (prop->length != sizeof(u32)) |
| 2051 | continue; |
| 2052 | |
| 2053 | func = __rtas_name_to_function(prop->name); |
| 2054 | if (!func) |
| 2055 | continue; |
| 2056 | |
| 2057 | func->token = be32_to_cpup((__be32 *)prop->value); |
| 2058 | |
| 2059 | pr_debug("function %s has token %u\n", func->name, func->token); |
| 2060 | } |
| 2061 | } |
| 2062 | |
| 2063 | /* |
| 2064 | * Call early during boot, before mem init, to retrieve the RTAS |
| 2065 | * information from the device-tree and allocate the RMO buffer for userland |
| 2066 | * accesses. |
| 2067 | */ |
| 2068 | void __init rtas_initialize(void) |
| 2069 | { |
| 2070 | unsigned long rtas_region = RTAS_INSTANTIATE_MAX; |
| 2071 | u32 base, size, entry; |
| 2072 | int no_base, no_size, no_entry; |
| 2073 | |
| 2074 | /* Get RTAS dev node and fill up our "rtas" structure with infos |
| 2075 | * about it. |
| 2076 | */ |
| 2077 | rtas.dev = of_find_node_by_name(NULL, "rtas"); |
| 2078 | if (!rtas.dev) |
| 2079 | return; |
| 2080 | |
| 2081 | no_base = of_property_read_u32(rtas.dev, "linux,rtas-base", &base); |
| 2082 | no_size = of_property_read_u32(rtas.dev, "rtas-size", &size); |
| 2083 | if (no_base || no_size) { |
| 2084 | of_node_put(rtas.dev); |
| 2085 | rtas.dev = NULL; |
| 2086 | return; |
| 2087 | } |
| 2088 | |
| 2089 | rtas.base = base; |
| 2090 | rtas.size = size; |
| 2091 | no_entry = of_property_read_u32(rtas.dev, "linux,rtas-entry", &entry); |
| 2092 | rtas.entry = no_entry ? rtas.base : entry; |
| 2093 | |
| 2094 | init_error_log_max(); |
| 2095 | |
| 2096 | /* Must be called before any function token lookups */ |
| 2097 | rtas_function_table_init(); |
| 2098 | |
| 2099 | /* |
| 2100 | * Discover this now to avoid a device tree lookup in the |
| 2101 | * panic path. |
| 2102 | */ |
| 2103 | ibm_extended_os_term = of_property_read_bool(rtas.dev, "ibm,extended-os-term"); |
| 2104 | |
| 2105 | /* If RTAS was found, allocate the RMO buffer for it and look for |
| 2106 | * the stop-self token if any |
| 2107 | */ |
| 2108 | #ifdef CONFIG_PPC64 |
| 2109 | if (firmware_has_feature(FW_FEATURE_LPAR)) |
| 2110 | rtas_region = min(ppc64_rma_size, RTAS_INSTANTIATE_MAX); |
| 2111 | #endif |
| 2112 | rtas_rmo_buf = memblock_phys_alloc_range(RTAS_USER_REGION_SIZE, PAGE_SIZE, |
| 2113 | 0, rtas_region); |
| 2114 | if (!rtas_rmo_buf) |
| 2115 | panic("ERROR: RTAS: Failed to allocate %lx bytes below %pa\n", |
| 2116 | PAGE_SIZE, &rtas_region); |
| 2117 | |
| 2118 | rtas_work_area_reserve_arena(rtas_region); |
| 2119 | } |
| 2120 | |
| 2121 | int __init early_init_dt_scan_rtas(unsigned long node, |
| 2122 | const char *uname, int depth, void *data) |
| 2123 | { |
| 2124 | const u32 *basep, *entryp, *sizep; |
| 2125 | |
| 2126 | if (depth != 1 || strcmp(uname, "rtas") != 0) |
| 2127 | return 0; |
| 2128 | |
| 2129 | basep = of_get_flat_dt_prop(node, "linux,rtas-base", NULL); |
| 2130 | entryp = of_get_flat_dt_prop(node, "linux,rtas-entry", NULL); |
| 2131 | sizep = of_get_flat_dt_prop(node, "rtas-size", NULL); |
| 2132 | |
| 2133 | #ifdef CONFIG_PPC64 |
| 2134 | /* need this feature to decide the crashkernel offset */ |
| 2135 | if (of_get_flat_dt_prop(node, "ibm,hypertas-functions", NULL)) |
| 2136 | powerpc_firmware_features |= FW_FEATURE_LPAR; |
| 2137 | #endif |
| 2138 | |
| 2139 | if (basep && entryp && sizep) { |
| 2140 | rtas.base = *basep; |
| 2141 | rtas.entry = *entryp; |
| 2142 | rtas.size = *sizep; |
| 2143 | } |
| 2144 | |
| 2145 | #ifdef CONFIG_UDBG_RTAS_CONSOLE |
| 2146 | basep = of_get_flat_dt_prop(node, "put-term-char", NULL); |
| 2147 | if (basep) |
| 2148 | rtas_putchar_token = *basep; |
| 2149 | |
| 2150 | basep = of_get_flat_dt_prop(node, "get-term-char", NULL); |
| 2151 | if (basep) |
| 2152 | rtas_getchar_token = *basep; |
| 2153 | |
| 2154 | if (rtas_putchar_token != RTAS_UNKNOWN_SERVICE && |
| 2155 | rtas_getchar_token != RTAS_UNKNOWN_SERVICE) |
| 2156 | udbg_init_rtas_console(); |
| 2157 | |
| 2158 | #endif |
| 2159 | |
| 2160 | /* break now */ |
| 2161 | return 1; |
| 2162 | } |
| 2163 | |
| 2164 | static DEFINE_RAW_SPINLOCK(timebase_lock); |
| 2165 | static u64 timebase = 0; |
| 2166 | |
| 2167 | void rtas_give_timebase(void) |
| 2168 | { |
| 2169 | unsigned long flags; |
| 2170 | |
| 2171 | raw_spin_lock_irqsave(&timebase_lock, flags); |
| 2172 | hard_irq_disable(); |
| 2173 | rtas_call(rtas_function_token(RTAS_FN_FREEZE_TIME_BASE), 0, 1, NULL); |
| 2174 | timebase = get_tb(); |
| 2175 | raw_spin_unlock(&timebase_lock); |
| 2176 | |
| 2177 | while (timebase) |
| 2178 | barrier(); |
| 2179 | rtas_call(rtas_function_token(RTAS_FN_THAW_TIME_BASE), 0, 1, NULL); |
| 2180 | local_irq_restore(flags); |
| 2181 | } |
| 2182 | |
| 2183 | void rtas_take_timebase(void) |
| 2184 | { |
| 2185 | while (!timebase) |
| 2186 | barrier(); |
| 2187 | raw_spin_lock(&timebase_lock); |
| 2188 | set_tb(timebase >> 32, timebase & 0xffffffff); |
| 2189 | timebase = 0; |
| 2190 | raw_spin_unlock(&timebase_lock); |
| 2191 | } |