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 #include <sys/syslog.h> 12 13 #define FDO_BUG_MSG "Please file a bug on drm/i915; see " FDO_BUG_URL " for details." 14 15 void 16 __i915_printk(struct drm_i915_private *dev_priv, const char *level, 17 const char *fmt, ...) 18 { 19 static bool shown_bug_once; 20 struct device *kdev = dev_priv->drm.dev; 21 bool is_error = level[1] <= KERN_ERR[1]; 22 bool is_debug = level[1] == KERN_DEBUG[1]; 23 struct va_format vaf; 24 va_list args; 25 26 if (is_debug && !drm_debug_enabled(DRM_UT_DRIVER)) 27 return; 28 29 va_start(args, fmt); 30 31 vaf.fmt = fmt; 32 vaf.va = &args; 33 34 #ifdef __linux__ 35 if (is_error) 36 dev_printk(level, kdev, "%pV", &vaf); 37 else 38 dev_printk(level, kdev, "[" DRM_NAME ":%ps] %pV", 39 __builtin_return_address(0), &vaf); 40 #else 41 if (!is_error) 42 printf("[" DRM_NAME "] "); 43 vprintf(fmt, args); 44 #endif 45 46 va_end(args); 47 48 if (is_error && !shown_bug_once) { 49 /* 50 * Ask the user to file a bug report for the error, except 51 * if they may have caused the bug by fiddling with unsafe 52 * module parameters. 53 */ 54 #ifdef __linux__ 55 if (!test_taint(TAINT_USER)) 56 dev_notice(kdev, "%s", FDO_BUG_MSG); 57 #endif 58 shown_bug_once = true; 59 } 60 } 61 62 #if IS_ENABLED(CONFIG_DRM_I915_DEBUG) 63 static unsigned int i915_probe_fail_count; 64 65 int __i915_inject_probe_error(struct drm_i915_private *i915, int err, 66 const char *func, int line) 67 { 68 if (i915_probe_fail_count >= i915_modparams.inject_probe_failure) 69 return 0; 70 71 if (++i915_probe_fail_count < i915_modparams.inject_probe_failure) 72 return 0; 73 74 __i915_printk(i915, KERN_INFO, 75 "Injecting failure %d at checkpoint %u [%s:%d]\n", 76 err, i915_modparams.inject_probe_failure, func, line); 77 i915_modparams.inject_probe_failure = 0; 78 return err; 79 } 80 81 bool i915_error_injected(void) 82 { 83 return i915_probe_fail_count && !i915_modparams.inject_probe_failure; 84 } 85 86 #endif 87 88 void cancel_timer(struct timeout *t) 89 { 90 if (!READ_ONCE(t->to_time)) 91 return; 92 93 del_timer(t); 94 WRITE_ONCE(t->to_time, 0); 95 } 96 97 void set_timer_ms(struct timeout *t, unsigned long timeout) 98 { 99 if (!timeout) { 100 cancel_timer(t); 101 return; 102 } 103 104 timeout = msecs_to_jiffies_timeout(timeout); 105 106 /* 107 * Paranoia to make sure the compiler computes the timeout before 108 * loading 'jiffies' as jiffies is volatile and may be updated in 109 * the background by a timer tick. All to reduce the complexity 110 * of the addition and reduce the risk of losing a jiffie. 111 */ 112 barrier(); 113 114 mod_timer(t, jiffies + timeout); 115 } 116