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
 13void
 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
 52void add_taint_for_CI(struct drm_i915_private *i915, unsigned int taint)
 53{
 54	__i915_printk(i915, KERN_NOTICE, "CI tainted:%#x by %pS\n",
 55		      taint, (void *)_RET_IP_);
 56
 57	/* Failures that occur during fault injection testing are expected */
 58	if (!i915_error_injected())
 59		__add_taint_for_CI(taint);
 60}
 61
 62#if IS_ENABLED(CONFIG_DRM_I915_DEBUG)
 63static unsigned int i915_probe_fail_count;
 64
 65int __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
 81bool i915_error_injected(void)
 82{
 83	return i915_probe_fail_count && !i915_modparams.inject_probe_failure;
 84}
 85
 86#endif
 87
 88void cancel_timer(struct timer_list *t)
 89{
 90	if (!timer_active(t))
 91		return;
 92
 93	del_timer(t);
 94	WRITE_ONCE(t->expires, 0);
 95}
 96
 97void set_timer_ms(struct timer_list *t, unsigned long timeout)
 98{
 99	if (!timeout) {
100		cancel_timer(t);
101		return;
102	}
103
104	timeout = msecs_to_jiffies(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	/* Keep t->expires = 0 reserved to indicate a canceled timer. */
115	mod_timer(t, jiffies + timeout ?: 1);
116}