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1// SPDX-License-Identifier: MIT2/*3 * Copyright © 2019 Intel Corporation4 */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 14void 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)25static unsigned int i915_probe_fail_count;26 27int __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 43bool i915_error_injected(void)44{45 return i915_probe_fail_count && !i915_modparams.inject_probe_failure;46}47 48#endif49 50void 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 59void 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 before70 * loading 'jiffies' as jiffies is volatile and may be updated in71 * the background by a timer tick. All to reduce the complexity72 * 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 80bool 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 89bool i915_direct_stolen_access(struct drm_i915_private *i915)90{91 /*92 * Wa_2201844407493 *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 firmware98 * 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