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(dev: 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(uncore: &i915->uncore, MTL_PCODE_STOLEN_ACCESS) == STOLEN_ACCESS_ALLOWED;
74}
75

source code of linux/drivers/gpu/drm/i915/i915_utils.c