1 // SPDX-License-Identifier: MIT 2 /* 3 * Copyright © 2019 Intel Corporation 4 */ 5 6 #include <linux/device.h> 7 8 #include <drm/drm_drv.h> 9 10 #include "i915_drv.h" 11 #include "i915_reg.h" 12 #include "i915_utils.h" 13 14 #define FDO_BUG_MSG "Please file a bug on drm/i915; see " FDO_BUG_URL " for details." 15 16 void 17 __i915_printk(struct drm_i915_private *dev_priv, const char *level, 18 const char *fmt, ...) 19 { 20 static bool shown_bug_once; 21 struct device *kdev = dev_priv->drm.dev; 22 bool is_error = level[1] <= KERN_ERR[1]; 23 bool is_debug = level[1] == KERN_DEBUG[1]; 24 struct va_format vaf; 25 va_list args; 26 27 if (is_debug && !drm_debug_enabled(DRM_UT_DRIVER)) 28 return; 29 30 va_start(args, fmt); 31 32 vaf.fmt = fmt; 33 vaf.va = &args; 34 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 41 va_end(args); 42 43 if (is_error && !shown_bug_once) { 44 /* 45 * Ask the user to file a bug report for the error, except 46 * if they may have caused the bug by fiddling with unsafe 47 * module parameters. 48 */ 49 if (!test_taint(TAINT_USER)) 50 dev_notice(kdev, "%s", FDO_BUG_MSG); 51 shown_bug_once = true; 52 } 53 } 54 55 void add_taint_for_CI(struct drm_i915_private *i915, unsigned int taint) 56 { 57 __i915_printk(i915, KERN_NOTICE, "CI tainted:%#x by %pS\n", 58 taint, (void *)_RET_IP_); 59 60 /* Failures that occur during fault injection testing are expected */ 61 if (!i915_error_injected()) 62 __add_taint_for_CI(taint); 63 } 64 65 #if IS_ENABLED(CONFIG_DRM_I915_DEBUG) 66 static unsigned int i915_probe_fail_count; 67 68 int __i915_inject_probe_error(struct drm_i915_private *i915, int err, 69 const char *func, int line) 70 { 71 if (i915_probe_fail_count >= i915_modparams.inject_probe_failure) 72 return 0; 73 74 if (++i915_probe_fail_count < i915_modparams.inject_probe_failure) 75 return 0; 76 77 __i915_printk(i915, KERN_INFO, 78 "Injecting failure %d at checkpoint %u [%s:%d]\n", 79 err, i915_modparams.inject_probe_failure, func, line); 80 i915_modparams.inject_probe_failure = 0; 81 return err; 82 } 83 84 bool i915_error_injected(void) 85 { 86 return i915_probe_fail_count && !i915_modparams.inject_probe_failure; 87 } 88 89 #endif 90 91 void cancel_timer(struct timer_list *t) 92 { 93 if (!timer_active(t)) 94 return; 95 96 del_timer(t); 97 WRITE_ONCE(t->expires, 0); 98 } 99 100 void set_timer_ms(struct timer_list *t, unsigned long timeout) 101 { 102 if (!timeout) { 103 cancel_timer(t); 104 return; 105 } 106 107 timeout = msecs_to_jiffies(timeout); 108 109 /* 110 * Paranoia to make sure the compiler computes the timeout before 111 * loading 'jiffies' as jiffies is volatile and may be updated in 112 * the background by a timer tick. All to reduce the complexity 113 * of the addition and reduce the risk of losing a jiffie. 114 */ 115 barrier(); 116 117 /* Keep t->expires = 0 reserved to indicate a canceled timer. */ 118 mod_timer(t, jiffies + timeout ?: 1); 119 } 120 121 bool i915_vtd_active(struct drm_i915_private *i915) 122 { 123 if (device_iommu_mapped(i915->drm.dev)) 124 return true; 125 126 /* Running as a guest, we assume the host is enforcing VT'd */ 127 return i915_run_as_guest(); 128 } 129 130 bool i915_direct_stolen_access(struct drm_i915_private *i915) 131 { 132 /* 133 * Wa_22018444074 134 * 135 * Access via BAR can hang MTL, go directly to GSM/DSM, 136 * except for VM guests which won't have access to it. 137 * 138 * Normally this would not work but on MTL the system firmware 139 * should have relaxed the access permissions sufficiently. 140 * 0x138914==0x1 indicates that the firmware has done its job. 141 */ 142 return IS_METEORLAKE(i915) && !i915_run_as_guest() && 143 intel_uncore_read(&i915->uncore, MTL_PCODE_STOLEN_ACCESS) == STOLEN_ACCESS_ALLOWED; 144 } 145