i915_utils.h

  1/*
  2 * Copyright © 2016 Intel Corporation
  3 *
  4 * Permission is hereby granted, free of charge, to any person obtaining a
  5 * copy of this software and associated documentation files (the "Software"),
  6 * to deal in the Software without restriction, including without limitation
  7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  8 * and/or sell copies of the Software, and to permit persons to whom the
  9 * Software is furnished to do so, subject to the following conditions:
 10 *
 11 * The above copyright notice and this permission notice (including the next
 12 * paragraph) shall be included in all copies or substantial portions of the
 13 * Software.
 14 *
 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 21 * IN THE SOFTWARE.
 22 *
 23 */
 24
 25#ifndef __I915_UTILS_H
 26#define __I915_UTILS_H
 27
 28#include <linux/overflow.h>
 29#include <linux/sched.h>
 30#include <linux/string_helpers.h>
 31#include <linux/types.h>
 32#include <linux/workqueue.h>
 33#include <linux/sched/clock.h>
 34
 35#ifdef CONFIG_X86
 36#include <asm/hypervisor.h>
 37#endif
 38
 39struct drm_i915_private;
 40
 41#ifndef MISSING_CASE
 42#define MISSING_CASE(x) WARN(1, "Missing case (%s == %ld)\n", \
 43			     __stringify(x), (long)(x))
 44#endif
 45
 46#if IS_ENABLED(CONFIG_DRM_I915_DEBUG)
 47
 48int __i915_inject_probe_error(struct drm_i915_private *i915, int err,
 49			      const char *func, int line);
 50#define i915_inject_probe_error(_i915, _err) \
 51	__i915_inject_probe_error((_i915), (_err), __func__, __LINE__)
 52bool i915_error_injected(void);
 53
 54#else
 55
 56#define i915_inject_probe_error(i915, e) ({ BUILD_BUG_ON_INVALID(i915); 0; })
 57#define i915_error_injected() false
 58
 59#endif
 60
 61#define i915_inject_probe_failure(i915) i915_inject_probe_error((i915), -ENODEV)
 62
 63#define i915_probe_error(i915, fmt, ...) ({ \
 64	if (i915_error_injected()) \
 65		drm_dbg(&(i915)->drm, fmt, ##__VA_ARGS__); \
 66	else \
 67		drm_err(&(i915)->drm, fmt, ##__VA_ARGS__); \
 68})
 69
 70#ifndef fetch_and_zero
 71#define fetch_and_zero(ptr) ({						\
 72	typeof(*ptr) __T = *(ptr);					\
 73	*(ptr) = (typeof(*ptr))0;					\
 74	__T;								\
 75})
 76#endif
 77
 78/*
 79 * check_user_mbz: Check that a user value exists and is zero
 80 *
 81 * Frequently in our uABI we reserve space for future extensions, and
 82 * two ensure that userspace is prepared we enforce that space must
 83 * be zero. (Then any future extension can safely assume a default value
 84 * of 0.)
 85 *
 86 * check_user_mbz() combines checking that the user pointer is accessible
 87 * and that the contained value is zero.
 88 *
 89 * Returns: -EFAULT if not accessible, -EINVAL if !zero, or 0 on success.
 90 */
 91#define check_user_mbz(U) ({						\
 92	typeof(*(U)) mbz__;						\
 93	get_user(mbz__, (U)) ? -EFAULT : mbz__ ? -EINVAL : 0;		\
 94})
 95
 96#define __mask_next_bit(mask) ({					\
 97	int __idx = ffs(mask) - 1;					\
 98	mask &= ~BIT(__idx);						\
 99	__idx;								\
100})
101
102static inline bool is_power_of_2_u64(u64 n)
103{
104	return (n != 0 && ((n & (n - 1)) == 0));
105}
106
107void add_taint_for_CI(struct drm_i915_private *i915, unsigned int taint);
108static inline void __add_taint_for_CI(unsigned int taint)
109{
110	/*
111	 * The system is "ok", just about surviving for the user, but
112	 * CI results are now unreliable as the HW is very suspect.
113	 * CI checks the taint state after every test and will reboot
114	 * the machine if the kernel is tainted.
115	 */
116	add_taint(taint, LOCKDEP_STILL_OK);
117}
118
119static inline bool i915_run_as_guest(void)
120{
121#if IS_ENABLED(CONFIG_X86)
122	return !hypervisor_is_type(X86_HYPER_NATIVE);
123#else
124	/* Not supported yet */
125	return false;
126#endif
127}
128
129bool i915_vtd_active(struct drm_i915_private *i915);
130
131bool i915_direct_stolen_access(struct drm_i915_private *i915);
132
133#endif /* !__I915_UTILS_H */