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