1/* 2 * Copyright �� 2016 Intel Corporation 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining a 5 * copy of this software and associated documentation files (the "Software"), 6 * to deal in the Software without restriction, including without limitation 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 8 * and/or sell copies of the Software, and to permit persons to whom the 9 * Software is furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice (including the next 12 * paragraph) shall be included in all copies or substantial portions of the 13 * Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS 21 * IN THE SOFTWARE. 22 * 23 */ 24 25#ifndef __I915_UTILS_H 26#define __I915_UTILS_H 27 28#include <linux/list.h> 29#include <linux/overflow.h> 30#include <linux/sched.h> 31#include <linux/string_helpers.h> 32#include <linux/types.h> 33#include <linux/workqueue.h> 34#include <linux/sched/clock.h> 35 36#ifdef CONFIG_X86 37#include <asm/hypervisor.h> 38#endif 39 40struct drm_i915_private; 41struct timer_list; 42 43#define FDO_BUG_URL "https://drm.pages.freedesktop.org/intel-docs/how-to-file-i915-bugs.html" 44 45#define MISSING_CASE(x) WARN(1, "Missing case (%s == %ld)\n", \ 46 __stringify(x), (long)(x)) 47 48void __printf(3, 4) 49__i915_printk(struct drm_i915_private *dev_priv, const char *level, 50 const char *fmt, ...); 51 52#define i915_report_error(dev_priv, fmt, ...) \ 53 __i915_printk(dev_priv, KERN_ERR, fmt, ##__VA_ARGS__) 54 55#if IS_ENABLED(CONFIG_DRM_I915_DEBUG) 56 57int __i915_inject_probe_error(struct drm_i915_private *i915, int err, 58 const char *func, int line); 59#define i915_inject_probe_error(_i915, _err) \ 60 __i915_inject_probe_error((_i915), (_err), __func__, __LINE__) 61bool i915_error_injected(void); 62 63#else 64 65#define i915_inject_probe_error(i915, e) ({ BUILD_BUG_ON_INVALID(i915); 0; }) 66#define i915_error_injected() false 67 68#endif 69 70#define i915_inject_probe_failure(i915) i915_inject_probe_error((i915), -ENODEV) 71 72#define i915_probe_error(i915, fmt, ...) \ 73 __i915_printk(i915, i915_error_injected() ? KERN_DEBUG : KERN_ERR, \ 74 fmt, ##__VA_ARGS__) 75 76#if defined(GCC_VERSION) && GCC_VERSION >= 70000 77#define add_overflows_t(T, A, B) \ 78 __builtin_add_overflow_p((A), (B), (T)0) 79#else 80#define add_overflows_t(T, A, B) ({ \ 81 typeof(A) a = (A); \ 82 typeof(B) b = (B); \ 83 (T)(a + b) < a; \ 84}) 85#endif 86 87#define add_overflows(A, B) \ 88 add_overflows_t(typeof((A) + (B)), (A), (B)) 89 90#define range_overflows(start, size, max) ({ \ 91 typeof(start) start__ = (start); \ 92 typeof(size) size__ = (size); \ 93 typeof(max) max__ = (max); \ 94 (void)(&start__ == &size__); \ 95 (void)(&start__ == &max__); \ 96 start__ >= max__ || size__ > max__ - start__; \ 97}) 98 99#define range_overflows_t(type, start, size, max) \ 100 range_overflows((type)(start), (type)(size), (type)(max)) 101 102#define range_overflows_end(start, size, max) ({ \ 103 typeof(start) start__ = (start); \ 104 typeof(size) size__ = (size); \ 105 typeof(max) max__ = (max); \ 106 (void)(&start__ == &size__); \ 107 (void)(&start__ == &max__); \ 108 start__ > max__ || size__ > max__ - start__; \ 109}) 110 111#define range_overflows_end_t(type, start, size, max) \ 112 range_overflows_end((type)(start), (type)(size), (type)(max)) 113 114#define ptr_mask_bits(ptr, n) ({ \ 115 unsigned long __v = (unsigned long)(ptr); \ 116 (typeof(ptr))(__v & -BIT(n)); \ 117}) 118 119#define ptr_unmask_bits(ptr, n) ((unsigned long)(ptr) & (BIT(n) - 1)) 120 121#define ptr_unpack_bits(ptr, bits, n) ({ \ 122 unsigned long __v = (unsigned long)(ptr); \ 123 *(bits) = __v & (BIT(n) - 1); \ 124 (typeof(ptr))(__v & -BIT(n)); \ 125}) 126 127#define ptr_pack_bits(ptr, bits, n) ({ \ 128 unsigned long __bits = (bits); \ 129 GEM_BUG_ON(__bits & -BIT(n)); \ 130 ((typeof(ptr))((unsigned long)(ptr) | __bits)); \ 131}) 132 133#define ptr_dec(ptr) ({ \ 134 unsigned long __v = (unsigned long)(ptr); \ 135 (typeof(ptr))(__v - 1); \ 136}) 137 138#define ptr_inc(ptr) ({ \ 139 unsigned long __v = (unsigned long)(ptr); \ 140 (typeof(ptr))(__v + 1); \ 141}) 142 143#define page_mask_bits(ptr) ptr_mask_bits(ptr, PAGE_SHIFT) 144#define page_unmask_bits(ptr) ptr_unmask_bits(ptr, PAGE_SHIFT) 145#define page_pack_bits(ptr, bits) ptr_pack_bits(ptr, bits, PAGE_SHIFT) 146#define page_unpack_bits(ptr, bits) ptr_unpack_bits(ptr, bits, PAGE_SHIFT) 147 148#define fetch_and_zero(ptr) ({ \ 149 typeof(*ptr) __T = *(ptr); \ 150 *(ptr) = (typeof(*ptr))0; \ 151 __T; \ 152}) 153 154static __always_inline ptrdiff_t ptrdiff(const void *a, const void *b) 155{ 156 return a - b; 157} 158 159/* 160 * container_of_user: Extract the superclass from a pointer to a member. 161 * 162 * Exactly like container_of() with the exception that it plays nicely 163 * with sparse for __user @ptr. 164 */ 165#define container_of_user(ptr, type, member) ({ \ 166 void __user *__mptr = (void __user *)(ptr); \ 167 BUILD_BUG_ON_MSG(!__same_type(*(ptr), typeof_member(type, member)) && \ 168 !__same_type(*(ptr), void), \ 169 "pointer type mismatch in container_of()"); \ 170 ((type __user *)(__mptr - offsetof(type, member))); }) 171 172/* 173 * check_user_mbz: Check that a user value exists and is zero 174 * 175 * Frequently in our uABI we reserve space for future extensions, and 176 * two ensure that userspace is prepared we enforce that space must 177 * be zero. (Then any future extension can safely assume a default value 178 * of 0.) 179 * 180 * check_user_mbz() combines checking that the user pointer is accessible 181 * and that the contained value is zero. 182 * 183 * Returns: -EFAULT if not accessible, -EINVAL if !zero, or 0 on success. 184 */ 185#define check_user_mbz(U) ({ \ 186 typeof(*(U)) mbz__; \ 187 get_user(mbz__, (U)) ? -EFAULT : mbz__ ? -EINVAL : 0; \ 188}) 189 190#define u64_to_ptr(T, x) ({ \ 191 typecheck(u64, x); \ 192 (T *)(uintptr_t)(x); \ 193}) 194 195#define __mask_next_bit(mask) ({ \ 196 int __idx = ffs(mask) - 1; \ 197 mask &= ~BIT(__idx); \ 198 __idx; \ 199}) 200 201static inline bool is_power_of_2_u64(u64 n) 202{ 203 return (n != 0 && ((n & (n - 1)) == 0)); 204} 205 206static inline void __list_del_many(struct list_head *head, 207 struct list_head *first) 208{ 209 first->prev = head; 210 WRITE_ONCE(head->next, first); 211} 212 213static inline int list_is_last_rcu(const struct list_head *list, 214 const struct list_head *head) 215{ 216 return READ_ONCE(list->next) == head; 217} 218 219static inline unsigned long msecs_to_jiffies_timeout(const unsigned int m) 220{ 221 unsigned long j = msecs_to_jiffies(m); 222 223 return min_t(unsigned long, MAX_JIFFY_OFFSET, j + 1); 224} 225 226/* 227 * If you need to wait X milliseconds between events A and B, but event B 228 * doesn't happen exactly after event A, you record the timestamp (jiffies) of 229 * when event A happened, then just before event B you call this function and 230 * pass the timestamp as the first argument, and X as the second argument. 231 */ 232static inline void 233wait_remaining_ms_from_jiffies(unsigned long timestamp_jiffies, int to_wait_ms) 234{ 235 unsigned long target_jiffies, tmp_jiffies, remaining_jiffies; 236 237 /* 238 * Don't re-read the value of "jiffies" every time since it may change 239 * behind our back and break the math. 240 */ 241 tmp_jiffies = jiffies; 242 target_jiffies = timestamp_jiffies + 243 msecs_to_jiffies_timeout(to_wait_ms); 244 245 if (time_after(target_jiffies, tmp_jiffies)) { 246 remaining_jiffies = target_jiffies - tmp_jiffies; 247 while (remaining_jiffies) 248 remaining_jiffies = 249 schedule_timeout_uninterruptible(remaining_jiffies); 250 } 251} 252 253/* 254 * __wait_for - magic wait macro 255 * 256 * Macro to help avoid open coding check/wait/timeout patterns. Note that it's 257 * important that we check the condition again after having timed out, since the 258 * timeout could be due to preemption or similar and we've never had a chance to 259 * check the condition before the timeout. 260 */ 261#define __wait_for(OP, COND, US, Wmin, Wmax) ({ \ 262 const ktime_t end__ = ktime_add_ns(ktime_get_raw(), 1000ll * (US)); \ 263 long wait__ = (Wmin); /* recommended min for usleep is 10 us */ \ 264 int ret__; \ 265 might_sleep(); \ 266 for (;;) { \ 267 const bool expired__ = ktime_after(ktime_get_raw(), end__); \ 268 OP; \ 269 /* Guarantee COND check prior to timeout */ \ 270 barrier(); \ 271 if (COND) { \ 272 ret__ = 0; \ 273 break; \ 274 } \ 275 if (expired__) { \ 276 ret__ = -ETIMEDOUT; \ 277 break; \ 278 } \ 279 usleep_range(wait__, wait__ * 2); \ 280 if (wait__ < (Wmax)) \ 281 wait__ <<= 1; \ 282 } \ 283 ret__; \ 284}) 285 286#define _wait_for(COND, US, Wmin, Wmax) __wait_for(, (COND), (US), (Wmin), \ 287 (Wmax)) 288#define wait_for(COND, MS) _wait_for((COND), (MS) * 1000, 10, 1000) 289 290/* If CONFIG_PREEMPT_COUNT is disabled, in_atomic() always reports false. */ 291#if defined(CONFIG_DRM_I915_DEBUG) && defined(CONFIG_PREEMPT_COUNT) 292# define _WAIT_FOR_ATOMIC_CHECK(ATOMIC) WARN_ON_ONCE((ATOMIC) && !in_atomic()) 293#else 294# define _WAIT_FOR_ATOMIC_CHECK(ATOMIC) do { } while (0) 295#endif 296 297#define _wait_for_atomic(COND, US, ATOMIC) \ 298({ \ 299 int cpu, ret, timeout = (US) * 1000; \ 300 u64 base; \ 301 _WAIT_FOR_ATOMIC_CHECK(ATOMIC); \ 302 if (!(ATOMIC)) { \ 303 preempt_disable(); \ 304 cpu = smp_processor_id(); \ 305 } \ 306 base = local_clock(); \ 307 for (;;) { \ 308 u64 now = local_clock(); \ 309 if (!(ATOMIC)) \ 310 preempt_enable(); \ 311 /* Guarantee COND check prior to timeout */ \ 312 barrier(); \ 313 if (COND) { \ 314 ret = 0; \ 315 break; \ 316 } \ 317 if (now - base >= timeout) { \ 318 ret = -ETIMEDOUT; \ 319 break; \ 320 } \ 321 cpu_relax(); \ 322 if (!(ATOMIC)) { \ 323 preempt_disable(); \ 324 if (unlikely(cpu != smp_processor_id())) { \ 325 timeout -= now - base; \ 326 cpu = smp_processor_id(); \ 327 base = local_clock(); \ 328 } \ 329 } \ 330 } \ 331 ret; \ 332}) 333 334#define wait_for_us(COND, US) \ 335({ \ 336 int ret__; \ 337 BUILD_BUG_ON(!__builtin_constant_p(US)); \ 338 if ((US) > 10) \ 339 ret__ = _wait_for((COND), (US), 10, 10); \ 340 else \ 341 ret__ = _wait_for_atomic((COND), (US), 0); \ 342 ret__; \ 343}) 344 345#define wait_for_atomic_us(COND, US) \ 346({ \ 347 BUILD_BUG_ON(!__builtin_constant_p(US)); \ 348 BUILD_BUG_ON((US) > 50000); \ 349 _wait_for_atomic((COND), (US), 1); \ 350}) 351 352#define wait_for_atomic(COND, MS) wait_for_atomic_us((COND), (MS) * 1000) 353 354#define KHz(x) (1000 * (x)) 355#define MHz(x) KHz(1000 * (x)) 356 357void add_taint_for_CI(struct drm_i915_private *i915, unsigned int taint); 358static inline void __add_taint_for_CI(unsigned int taint) 359{ 360 /* 361 * The system is "ok", just about surviving for the user, but 362 * CI results are now unreliable as the HW is very suspect. 363 * CI checks the taint state after every test and will reboot 364 * the machine if the kernel is tainted. 365 */ 366 add_taint(taint, LOCKDEP_STILL_OK); 367} 368 369void cancel_timer(struct timer_list *t); 370void set_timer_ms(struct timer_list *t, unsigned long timeout); 371 372static inline bool timer_active(const struct timer_list *t) 373{ 374 return READ_ONCE(t->expires); 375} 376 377static inline bool timer_expired(const struct timer_list *t) 378{ 379 return timer_active(t) && !timer_pending(t); 380} 381 382static inline bool i915_run_as_guest(void) 383{ 384#if IS_ENABLED(CONFIG_X86) 385 return !hypervisor_is_type(X86_HYPER_NATIVE); 386#else 387 /* Not supported yet */ 388 return false; 389#endif 390} 391 392bool i915_vtd_active(struct drm_i915_private *i915); 393 394bool i915_direct_stolen_access(struct drm_i915_private *i915); 395 396#endif /* !__I915_UTILS_H */ 397