1 /* $NetBSD: i915_utils.h,v 1.6 2022/05/27 21:02:27 riastradh Exp $ */ 2 3 /* 4 * Copyright 2016 Intel Corporation 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a 7 * copy of this software and associated documentation files (the "Software"), 8 * to deal in the Software without restriction, including without limitation 9 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 10 * and/or sell copies of the Software, and to permit persons to whom the 11 * Software is furnished to do so, subject to the following conditions: 12 * 13 * The above copyright notice and this permission notice (including the next 14 * paragraph) shall be included in all copies or substantial portions of the 15 * Software. 16 * 17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 20 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 22 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS 23 * IN THE SOFTWARE. 24 * 25 */ 26 27 #ifndef __I915_UTILS_H 28 #define __I915_UTILS_H 29 30 #include <linux/list.h> 31 #include <linux/overflow.h> 32 #include <linux/sched.h> 33 #include <linux/sched/clock.h> 34 #include <linux/types.h> 35 #include <linux/workqueue.h> 36 37 struct drm_i915_private; 38 struct timer_list; 39 40 #undef WARN_ON 41 /* Many gcc seem to no see through this and fall over :( */ 42 #if 0 43 #define WARN_ON(x) ({ \ 44 bool __i915_warn_cond = (x); \ 45 if (__builtin_constant_p(__i915_warn_cond)) \ 46 BUILD_BUG_ON(__i915_warn_cond); \ 47 WARN(__i915_warn_cond, "WARN_ON(" #x ")\n"); }) 48 #else 49 #define WARN_ON(x) WARN((x), "%s\n", "WARN_ON(" __stringify(x) ")") 50 #endif 51 52 #undef WARN_ON_ONCE 53 #define WARN_ON_ONCE(x) WARN_ONCE((x), "%s", "WARN_ON_ONCE(" __stringify(x) ")\n") 54 55 #define MISSING_CASE(x) WARN(1, "Missing case (%s == %ld)\n", \ 56 __stringify(x), (long)(x)) 57 58 void __printf(3, 4) 59 __i915_printk(struct drm_i915_private *dev_priv, const char *level, 60 const char *fmt, ...); 61 62 #define i915_report_error(dev_priv, fmt, ...) \ 63 __i915_printk(dev_priv, KERN_ERR, fmt, ##__VA_ARGS__) 64 65 #if IS_ENABLED(CONFIG_DRM_I915_DEBUG) 66 67 int __i915_inject_probe_error(struct drm_i915_private *i915, int err, 68 const char *func, int line); 69 #define i915_inject_probe_error(_i915, _err) \ 70 __i915_inject_probe_error((_i915), (_err), __func__, __LINE__) 71 bool i915_error_injected(void); 72 73 #else 74 75 #define i915_inject_probe_error(i915, e) ({ BUILD_BUG_ON_INVALID(i915); 0; }) 76 #define i915_error_injected() false 77 78 #endif 79 80 #define i915_inject_probe_failure(i915) i915_inject_probe_error((i915), -ENODEV) 81 82 #define i915_probe_error(i915, fmt, ...) \ 83 __i915_printk(i915, i915_error_injected() ? KERN_DEBUG : KERN_ERR, \ 84 fmt, ##__VA_ARGS__) 85 86 #if defined(GCC_VERSION) && GCC_VERSION >= 70000 87 #define add_overflows_t(T, A, B) \ 88 __builtin_add_overflow_p((A), (B), (T)0) 89 #else 90 #define add_overflows_t(T, A, B) ({ \ 91 typeof(A) a = (A); \ 92 typeof(B) b = (B); \ 93 (T)(a + b) < a; \ 94 }) 95 #endif 96 97 #define add_overflows(A, B) \ 98 add_overflows_t(typeof((A) + (B)), (A), (B)) 99 100 #define range_overflows(start, size, max) ({ \ 101 typeof(start) start__ = (start); \ 102 typeof(size) size__ = (size); \ 103 typeof(max) max__ = (max); \ 104 (void)(&start__ == &size__); \ 105 (void)(&start__ == &max__); \ 106 start__ > max__ || size__ > max__ - start__; \ 107 }) 108 109 #define range_overflows_t(type, start, size, max) \ 110 range_overflows((type)(start), (type)(size), (type)(max)) 111 112 /* Note we don't consider signbits :| */ 113 #define overflows_type(x, T) \ 114 (sizeof(x) > sizeof(T) && (x) >> BITS_PER_TYPE(T)) 115 116 static inline bool 117 __check_struct_size(size_t base, size_t arr, size_t count, size_t *size) 118 { 119 size_t sz; 120 121 if (check_mul_overflow(count, arr, &sz)) 122 return false; 123 124 if (check_add_overflow(sz, base, &sz)) 125 return false; 126 127 *size = sz; 128 return true; 129 } 130 131 /** 132 * check_struct_size() - Calculate size of structure with trailing array. 133 * @p: Pointer to the structure. 134 * @member: Name of the array member. 135 * @n: Number of elements in the array. 136 * @sz: Total size of structure and array 137 * 138 * Calculates size of memory needed for structure @p followed by an 139 * array of @n @member elements, like struct_size() but reports 140 * whether it overflowed, and the resultant size in @sz 141 * 142 * Return: false if the calculation overflowed. 143 */ 144 #define check_struct_size(p, member, n, sz) \ 145 likely(__check_struct_size(sizeof(*(p)), \ 146 sizeof(*(p)->member) + __must_be_array((p)->member), \ 147 n, sz)) 148 149 #define ptr_mask_bits(ptr, n) ({ \ 150 unsigned long __v = (unsigned long)(ptr); \ 151 (typeof(ptr))(__v & -BIT(n)); \ 152 }) 153 154 #define ptr_unmask_bits(ptr, n) ((unsigned long)(ptr) & (BIT(n) - 1)) 155 156 #define ptr_unpack_bits(ptr, bits, n) ({ \ 157 unsigned long __v = (unsigned long)(ptr); \ 158 *(bits) = __v & (BIT(n) - 1); \ 159 (typeof(ptr))(__v & -BIT(n)); \ 160 }) 161 162 #define ptr_pack_bits(ptr, bits, n) ({ \ 163 unsigned long __bits = (bits); \ 164 GEM_BUG_ON(__bits & -BIT(n)); \ 165 ((typeof(ptr))((unsigned long)(ptr) | __bits)); \ 166 }) 167 168 #define ptr_dec(ptr) ({ \ 169 unsigned long __v = (unsigned long)(ptr); \ 170 (typeof(ptr))(__v - 1); \ 171 }) 172 173 #define ptr_inc(ptr) ({ \ 174 unsigned long __v = (unsigned long)(ptr); \ 175 (typeof(ptr))(__v + 1); \ 176 }) 177 178 #define page_mask_bits(ptr) ptr_mask_bits(ptr, PAGE_SHIFT) 179 #define page_unmask_bits(ptr) ptr_unmask_bits(ptr, PAGE_SHIFT) 180 #define page_pack_bits(ptr, bits) ptr_pack_bits(ptr, bits, PAGE_SHIFT) 181 #define page_unpack_bits(ptr, bits) ptr_unpack_bits(ptr, bits, PAGE_SHIFT) 182 183 #define struct_member(T, member) (((T *)0)->member) 184 185 #define ptr_offset(ptr, member) offsetof(typeof(*(ptr)), member) 186 187 #define fetch_and_zero(ptr) ({ \ 188 typeof(*ptr) __T = *(ptr); \ 189 *(ptr) = (typeof(*ptr))0; \ 190 __T; \ 191 }) 192 193 /* 194 * container_of_user: Extract the superclass from a pointer to a member. 195 * 196 * Exactly like container_of() with the exception that it plays nicely 197 * with sparse for __user @ptr. 198 */ 199 #define container_of_user(ptr, type, member) ({ \ 200 void __user *__mptr = (void __user *)(ptr); \ 201 BUILD_BUG_ON_MSG(!__same_type(*(ptr), struct_member(type, member)) && \ 202 !__same_type(*(ptr), void), \ 203 "pointer type mismatch in container_of()"); \ 204 ((type __user *)(__mptr - offsetof(type, member))); }) 205 206 /* 207 * check_user_mbz: Check that a user value exists and is zero 208 * 209 * Frequently in our uABI we reserve space for future extensions, and 210 * two ensure that userspace is prepared we enforce that space must 211 * be zero. (Then any future extension can safely assume a default value 212 * of 0.) 213 * 214 * check_user_mbz() combines checking that the user pointer is accessible 215 * and that the contained value is zero. 216 * 217 * Returns: -EFAULT if not accessible, -EINVAL if !zero, or 0 on success. 218 */ 219 #define check_user_mbz(U) ({ \ 220 typeof(*(U)) mbz__; \ 221 get_user(mbz__, (U)) ? -EFAULT : mbz__ ? -EINVAL : 0; \ 222 }) 223 224 static inline u64 ptr_to_u64(const void *ptr) 225 { 226 return (uintptr_t)ptr; 227 } 228 229 #define u64_to_ptr(T, x) ({ \ 230 typecheck(u64, x); \ 231 (T *)(uintptr_t)(x); \ 232 }) 233 234 #define __mask_next_bit(mask) ({ \ 235 int __idx = ffs(mask) - 1; \ 236 mask &= ~BIT(__idx); \ 237 __idx; \ 238 }) 239 240 static inline void __list_del_many(struct list_head *head, 241 struct list_head *first) 242 { 243 first->prev = head; 244 WRITE_ONCE(head->next, first); 245 } 246 247 /* 248 * Wait until the work is finally complete, even if it tries to postpone 249 * by requeueing itself. Note, that if the worker never cancels itself, 250 * we will spin forever. 251 */ 252 static inline void drain_delayed_work(struct delayed_work *dw) 253 { 254 do { 255 while (flush_delayed_work(dw)) 256 ; 257 } while (delayed_work_pending(dw)); 258 } 259 260 static inline unsigned long msecs_to_jiffies_timeout(const unsigned int m) 261 { 262 unsigned long j = msecs_to_jiffies(m); 263 264 return min_t(unsigned long, MAX_JIFFY_OFFSET, j + 1); 265 } 266 267 /* 268 * If you need to wait X milliseconds between events A and B, but event B 269 * doesn't happen exactly after event A, you record the timestamp (jiffies) of 270 * when event A happened, then just before event B you call this function and 271 * pass the timestamp as the first argument, and X as the second argument. 272 */ 273 static inline void 274 wait_remaining_ms_from_jiffies(unsigned long timestamp_jiffies, int to_wait_ms) 275 { 276 unsigned long target_jiffies, tmp_jiffies, remaining_jiffies; 277 278 /* 279 * Don't re-read the value of "jiffies" every time since it may change 280 * behind our back and break the math. 281 */ 282 tmp_jiffies = jiffies; 283 target_jiffies = timestamp_jiffies + 284 msecs_to_jiffies_timeout(to_wait_ms); 285 286 if (time_after(target_jiffies, tmp_jiffies)) { 287 remaining_jiffies = target_jiffies - tmp_jiffies; 288 while (remaining_jiffies) 289 remaining_jiffies = 290 schedule_timeout_uninterruptible(remaining_jiffies); 291 } 292 } 293 294 /** 295 * __wait_for - magic wait macro 296 * 297 * Macro to help avoid open coding check/wait/timeout patterns. Note that it's 298 * important that we check the condition again after having timed out, since the 299 * timeout could be due to preemption or similar and we've never had a chance to 300 * check the condition before the timeout. 301 */ 302 #ifdef __NetBSD__ 303 #define __wait_for(OP, COND, US, Wmin, Wmax) ({ \ 304 int ret__ = 0; \ 305 if (cold) { \ 306 int ms__ = ((US) + 999)/1000; \ 307 for (;;) { \ 308 const bool expired__ = ms__-- == 0; \ 309 OP; \ 310 barrier(); \ 311 if (COND) { \ 312 ret__ = 0; \ 313 break; \ 314 } \ 315 if (expired__) { \ 316 ret__ = -ETIMEDOUT; \ 317 break; \ 318 } \ 319 DELAY(1000); \ 320 } \ 321 } else { \ 322 const ktime_t end__ = \ 323 ktime_add_ns(ktime_get_raw(), 1000ll * (US)); \ 324 long wait__ = (Wmin); \ 325 might_sleep(); \ 326 for (;;) { \ 327 const bool expired__ = \ 328 ktime_after(ktime_get_raw(), end__); \ 329 OP; \ 330 /* Guarantee COND check prior to timeout */ \ 331 barrier(); \ 332 if (COND) { \ 333 ret__ = 0; \ 334 break; \ 335 } \ 336 if (expired__) { \ 337 ret__ = -ETIMEDOUT; \ 338 break; \ 339 } \ 340 usleep_range(wait__, wait__ * 2); \ 341 if (wait__ < (Wmax)) \ 342 wait__ <<= 1; \ 343 } \ 344 } \ 345 ret__; \ 346 }) 347 #else /* !NetBSD */ 348 #define __wait_for(OP, COND, US, Wmin, Wmax) ({ \ 349 const ktime_t end__ = ktime_add_ns(ktime_get_raw(), 1000ll * (US)); \ 350 long wait__ = (Wmin); /* recommended min for usleep is 10 us */ \ 351 int ret__; \ 352 might_sleep(); \ 353 for (;;) { \ 354 const bool expired__ = ktime_after(ktime_get_raw(), end__); \ 355 OP; \ 356 /* Guarantee COND check prior to timeout */ \ 357 barrier(); \ 358 if (COND) { \ 359 ret__ = 0; \ 360 break; \ 361 } \ 362 if (expired__) { \ 363 ret__ = -ETIMEDOUT; \ 364 break; \ 365 } \ 366 usleep_range(wait__, wait__ * 2); \ 367 if (wait__ < (Wmax)) \ 368 wait__ <<= 1; \ 369 } \ 370 ret__; \ 371 }) 372 #endif 373 374 #define _wait_for(COND, US, Wmin, Wmax) __wait_for(, (COND), (US), (Wmin), \ 375 (Wmax)) 376 #define wait_for(COND, MS) _wait_for((COND), (MS) * 1000, 10, 1000) 377 378 /* If CONFIG_PREEMPT_COUNT is disabled, in_atomic() always reports false. */ 379 #if defined(CONFIG_DRM_I915_DEBUG) && defined(CONFIG_PREEMPT_COUNT) 380 # define _WAIT_FOR_ATOMIC_CHECK(ATOMIC) WARN_ON_ONCE((ATOMIC) && !in_atomic()) 381 #else 382 # define _WAIT_FOR_ATOMIC_CHECK(ATOMIC) do { } while (0) 383 #endif 384 385 #define _wait_for_atomic(COND, US, ATOMIC) \ 386 ({ \ 387 int cpu, ret, timeout = (US) * 1000; \ 388 u64 base; \ 389 _WAIT_FOR_ATOMIC_CHECK(ATOMIC); \ 390 if (!(ATOMIC)) { \ 391 preempt_disable(); \ 392 cpu = smp_processor_id(); \ 393 } \ 394 base = local_clock(); \ 395 for (;;) { \ 396 u64 now = local_clock(); \ 397 if (!(ATOMIC)) \ 398 preempt_enable(); \ 399 /* Guarantee COND check prior to timeout */ \ 400 barrier(); \ 401 if (COND) { \ 402 ret = 0; \ 403 break; \ 404 } \ 405 if (now - base >= timeout) { \ 406 ret = -ETIMEDOUT; \ 407 break; \ 408 } \ 409 cpu_relax(); \ 410 if (!(ATOMIC)) { \ 411 preempt_disable(); \ 412 if (unlikely(cpu != smp_processor_id())) { \ 413 timeout -= now - base; \ 414 cpu = smp_processor_id(); \ 415 base = local_clock(); \ 416 } \ 417 } \ 418 } \ 419 ret; \ 420 }) 421 422 #define wait_for_us(COND, US) \ 423 ({ \ 424 int ret__; \ 425 BUILD_BUG_ON(!__builtin_constant_p(US)); \ 426 if ((US) > 10) \ 427 ret__ = _wait_for((COND), (US), 10, 10); \ 428 else \ 429 ret__ = _wait_for_atomic((COND), (US), 0); \ 430 ret__; \ 431 }) 432 433 #define wait_for_atomic_us(COND, US) \ 434 ({ \ 435 BUILD_BUG_ON(!__builtin_constant_p(US)); \ 436 BUILD_BUG_ON((US) > 50000); \ 437 _wait_for_atomic((COND), (US), 1); \ 438 }) 439 440 #define wait_for_atomic(COND, MS) wait_for_atomic_us((COND), (MS) * 1000) 441 442 #define KHz(x) (1000 * (x)) 443 #define MHz(x) KHz(1000 * (x)) 444 445 #define KBps(x) (1000 * (x)) 446 #define MBps(x) KBps(1000 * (x)) 447 #define GBps(x) ((u64)1000 * MBps((x))) 448 449 static inline const char *yesno(bool v) 450 { 451 return v ? "yes" : "no"; 452 } 453 454 static inline const char *onoff(bool v) 455 { 456 return v ? "on" : "off"; 457 } 458 459 static inline const char *enableddisabled(bool v) 460 { 461 return v ? "enabled" : "disabled"; 462 } 463 464 static inline void add_taint_for_CI(unsigned int taint) 465 { 466 /* 467 * The system is "ok", just about surviving for the user, but 468 * CI results are now unreliable as the HW is very suspect. 469 * CI checks the taint state after every test and will reboot 470 * the machine if the kernel is tainted. 471 */ 472 add_taint(taint, LOCKDEP_STILL_OK); 473 } 474 475 void cancel_timer(struct timer_list *t); 476 void set_timer_ms(struct timer_list *t, unsigned long timeout); 477 478 #ifdef __NetBSD__ 479 static inline bool 480 timer_expired(const struct timer_list *t) 481 { 482 return callout_expired(__UNCONST(&t->tl_callout)); 483 } 484 #else 485 static inline bool timer_expired(const struct timer_list *t) 486 { 487 return READ_ONCE(t->expires) && !timer_pending(t); 488 } 489 #endif 490 491 /* 492 * This is a lookalike for IS_ENABLED() that takes a kconfig value, 493 * e.g. CONFIG_DRM_I915_SPIN_REQUEST, and evaluates whether it is non-zero 494 * i.e. whether the configuration is active. Wrapping up the config inside 495 * a boolean context prevents clang and smatch from complaining about potential 496 * issues in confusing logical-&& with bitwise-& for constants. 497 * 498 * Sadly IS_ENABLED() itself does not work with kconfig values. 499 * 500 * Returns 0 if @config is 0, 1 if set to any value. 501 */ 502 #define IS_ACTIVE(config) ((config) != 0) 503 504 #endif /* !__I915_UTILS_H */ 505
Indexes created Sat Sep 20 22:09:52 GMT 2025