1 // SPDX-License-Identifier: MIT 2 /* 3 * Copyright © 2019 Intel Corporation 4 */ 5 6 #include <drm/drm_drv.h> 7 8 #include "i915_drv.h" 9 #include "i915_utils.h" 10 11 #define FDO_BUG_URL "https://gitlab.freedesktop.org/drm/intel/-/wikis/How-to-file-i915-bugs" 12 #define FDO_BUG_MSG "Please file a bug on drm/i915; see " FDO_BUG_URL " for details." 13 14 void 15 __i915_printk(struct drm_i915_private *dev_priv, const char *level, 16 const char *fmt, ...) 17 { 18 static bool shown_bug_once; 19 struct device *kdev = dev_priv->drm.dev; 20 bool is_error = level[1] <= KERN_ERR[1]; 21 bool is_debug = level[1] == KERN_DEBUG[1]; 22 struct va_format vaf; 23 va_list args; 24 25 if (is_debug && !drm_debug_enabled(DRM_UT_DRIVER)) 26 return; 27 28 va_start(args, fmt); 29 30 vaf.fmt = fmt; 31 vaf.va = &args; 32 33 if (is_error) 34 dev_printk(level, kdev, "%pV", &vaf); 35 else 36 dev_printk(level, kdev, "[" DRM_NAME ":%ps] %pV", 37 __builtin_return_address(0), &vaf); 38 39 va_end(args); 40 41 if (is_error && !shown_bug_once) { 42 /* 43 * Ask the user to file a bug report for the error, except 44 * if they may have caused the bug by fiddling with unsafe 45 * module parameters. 46 */ 47 if (!test_taint(TAINT_USER)) 48 dev_notice(kdev, "%s", FDO_BUG_MSG); 49 shown_bug_once = true; 50 } 51 } 52 53 #if IS_ENABLED(CONFIG_DRM_I915_DEBUG) 54 static unsigned int i915_probe_fail_count; 55 56 int __i915_inject_probe_error(struct drm_i915_private *i915, int err, 57 const char *func, int line) 58 { 59 if (i915_probe_fail_count >= i915_modparams.inject_probe_failure) 60 return 0; 61 62 if (++i915_probe_fail_count < i915_modparams.inject_probe_failure) 63 return 0; 64 65 __i915_printk(i915, KERN_INFO, 66 "Injecting failure %d at checkpoint %u [%s:%d]\n", 67 err, i915_modparams.inject_probe_failure, func, line); 68 i915_modparams.inject_probe_failure = 0; 69 return err; 70 } 71 72 bool i915_error_injected(void) 73 { 74 return i915_probe_fail_count && !i915_modparams.inject_probe_failure; 75 } 76 77 #endif 78 79 void cancel_timer(struct timer_list *t) 80 { 81 if (!READ_ONCE(t->expires)) 82 return; 83 84 del_timer(t); 85 WRITE_ONCE(t->expires, 0); 86 } 87 88 void set_timer_ms(struct timer_list *t, unsigned long timeout) 89 { 90 if (!timeout) { 91 cancel_timer(t); 92 return; 93 } 94 95 timeout = msecs_to_jiffies_timeout(timeout); 96 97 /* 98 * Paranoia to make sure the compiler computes the timeout before 99 * loading 'jiffies' as jiffies is volatile and may be updated in 100 * the background by a timer tick. All to reduce the complexity 101 * of the addition and reduce the risk of losing a jiffie. 102 */ 103 barrier(); 104 105 mod_timer(t, jiffies + timeout); 106 } 107