i915_utils.c

 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#include <drm/drm_print.h>
10
11#include "i915_drv.h"
12#include "i915_reg.h"
13#include "i915_utils.h"
14
15void add_taint_for_CI(struct drm_i915_private *i915, unsigned int taint)
16{
17	drm_notice(&i915->drm, "CI tainted: %#x by %pS\n",
18		   taint, __builtin_return_address(0));
19
20	/* Failures that occur during fault injection testing are expected */
21	if (!i915_error_injected())
22		__add_taint_for_CI(taint);
23}
24
25#if IS_ENABLED(CONFIG_DRM_I915_DEBUG)
26static unsigned int i915_probe_fail_count;
27
28int __i915_inject_probe_error(struct drm_i915_private *i915, int err,
29			      const char *func, int line)
30{
31	if (i915_probe_fail_count >= i915_modparams.inject_probe_failure)
32		return 0;
33
34	if (++i915_probe_fail_count < i915_modparams.inject_probe_failure)
35		return 0;
36
37	drm_info(&i915->drm, "Injecting failure %d at checkpoint %u [%s:%d]\n",
38		 err, i915_modparams.inject_probe_failure, func, line);
39
40	i915_modparams.inject_probe_failure = 0;
41	return err;
42}
43
44bool i915_error_injected(void)
45{
46	return i915_probe_fail_count && !i915_modparams.inject_probe_failure;
47}
48
49#endif
50
51bool i915_vtd_active(struct drm_i915_private *i915)
52{
53	if (device_iommu_mapped(i915->drm.dev))
54		return true;
55
56	/* Running as a guest, we assume the host is enforcing VT'd */
57	return i915_run_as_guest();
58}
59
60bool i915_direct_stolen_access(struct drm_i915_private *i915)
61{
62	/*
63	 * Wa_22018444074
64	 *
65	 * Access via BAR can hang MTL, go directly to GSM/DSM,
66	 * except for VM guests which won't have access to it.
67	 *
68	 * Normally this would not work but on MTL the system firmware
69	 * should have relaxed the access permissions sufficiently.
70	 * 0x138914==0x1 indicates that the firmware has done its job.
71	 */
72	return IS_METEORLAKE(i915) && !i915_run_as_guest() &&
73		intel_uncore_read(&i915->uncore, MTL_PCODE_STOLEN_ACCESS) == STOLEN_ACCESS_ALLOWED;
74}