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 void add_taint_for_CI(struct drm_i915_private *i915, unsigned int taint) 15 { 16 drm_notice(&i915->drm, "CI tainted: %#x by %pS\n", 17 taint, __builtin_return_address(0)); 18 19 /* Failures that occur during fault injection testing are expected */ 20 if (!i915_error_injected()) 21 __add_taint_for_CI(taint); 22 } 23 24 #if IS_ENABLED(CONFIG_DRM_I915_DEBUG) 25 static unsigned int i915_probe_fail_count; 26 27 int __i915_inject_probe_error(struct drm_i915_private *i915, int err, 28 const char *func, int line) 29 { 30 if (i915_probe_fail_count >= i915_modparams.inject_probe_failure) 31 return 0; 32 33 if (++i915_probe_fail_count < i915_modparams.inject_probe_failure) 34 return 0; 35 36 drm_info(&i915->drm, "Injecting failure %d at checkpoint %u [%s:%d]\n", 37 err, i915_modparams.inject_probe_failure, func, line); 38 39 i915_modparams.inject_probe_failure = 0; 40 return err; 41 } 42 43 bool i915_error_injected(void) 44 { 45 return i915_probe_fail_count && !i915_modparams.inject_probe_failure; 46 } 47 48 #endif 49 50 void cancel_timer(struct timer_list *t) 51 { 52 if (!timer_active(t)) 53 return; 54 55 del_timer(t); 56 WRITE_ONCE(t->expires, 0); 57 } 58 59 void set_timer_ms(struct timer_list *t, unsigned long timeout) 60 { 61 if (!timeout) { 62 cancel_timer(t); 63 return; 64 } 65 66 timeout = msecs_to_jiffies(timeout); 67 68 /* 69 * Paranoia to make sure the compiler computes the timeout before 70 * loading 'jiffies' as jiffies is volatile and may be updated in 71 * the background by a timer tick. All to reduce the complexity 72 * of the addition and reduce the risk of losing a jiffy. 73 */ 74 barrier(); 75 76 /* Keep t->expires = 0 reserved to indicate a canceled timer. */ 77 mod_timer(t, jiffies + timeout ?: 1); 78 } 79 80 bool i915_vtd_active(struct drm_i915_private *i915) 81 { 82 if (device_iommu_mapped(i915->drm.dev)) 83 return true; 84 85 /* Running as a guest, we assume the host is enforcing VT'd */ 86 return i915_run_as_guest(); 87 } 88 89 bool i915_direct_stolen_access(struct drm_i915_private *i915) 90 { 91 /* 92 * Wa_22018444074 93 * 94 * Access via BAR can hang MTL, go directly to GSM/DSM, 95 * except for VM guests which won't have access to it. 96 * 97 * Normally this would not work but on MTL the system firmware 98 * should have relaxed the access permissions sufficiently. 99 * 0x138914==0x1 indicates that the firmware has done its job. 100 */ 101 return IS_METEORLAKE(i915) && !i915_run_as_guest() && 102 intel_uncore_read(&i915->uncore, MTL_PCODE_STOLEN_ACCESS) == STOLEN_ACCESS_ALLOWED; 103 } 104