1 /* 2 * SPDX-License-Identifier: MIT 3 * 4 * Copyright © 2016 Intel Corporation 5 */ 6 7 #ifndef __I915_TIMELINE_TYPES_H__ 8 #define __I915_TIMELINE_TYPES_H__ 9 10 #include <linux/list.h> 11 #include <linux/kref.h> 12 #include <linux/mutex.h> 13 #include <linux/rcupdate.h> 14 #include <linux/types.h> 15 16 #include "i915_active_types.h" 17 18 struct i915_vma; 19 struct i915_syncmap; 20 struct intel_gt; 21 struct intel_timeline_hwsp; 22 23 struct intel_timeline { 24 u64 fence_context; 25 u32 seqno; 26 27 struct mutex mutex; /* protects the flow of requests */ 28 29 /* 30 * pin_count and active_count track essentially the same thing: 31 * How many requests are in flight or may be under construction. 32 * 33 * We need two distinct counters so that we can assign different 34 * lifetimes to the events for different use-cases. For example, 35 * we want to permanently keep the timeline pinned for the kernel 36 * context so that we can issue requests at any time without having 37 * to acquire space in the GGTT. However, we want to keep tracking 38 * the activity (to be able to detect when we become idle) along that 39 * permanently pinned timeline and so end up requiring two counters. 40 * 41 * Note that the active_count is protected by the intel_timeline.mutex, 42 * but the pin_count is protected by a combination of serialisation 43 * from the intel_context caller plus internal atomicity. 44 */ 45 atomic_t pin_count; 46 atomic_t active_count; 47 48 const u32 *hwsp_seqno; 49 struct i915_vma *hwsp_ggtt; 50 u32 hwsp_offset; 51 52 struct intel_timeline_cacheline *hwsp_cacheline; 53 54 bool has_initial_breadcrumb; 55 56 /** 57 * List of breadcrumbs associated with GPU requests currently 58 * outstanding. 59 */ 60 struct list_head requests; 61 62 /* 63 * Contains an RCU guarded pointer to the last request. No reference is 64 * held to the request, users must carefully acquire a reference to 65 * the request using i915_active_fence_get(), or manage the RCU 66 * protection themselves (cf the i915_active_fence API). 67 */ 68 struct i915_active_fence last_request; 69 70 /** A chain of completed timelines ready for early retirement. */ 71 struct intel_timeline *retire; 72 73 /** 74 * We track the most recent seqno that we wait on in every context so 75 * that we only have to emit a new await and dependency on a more 76 * recent sync point. As the contexts may be executed out-of-order, we 77 * have to track each individually and can not rely on an absolute 78 * global_seqno. When we know that all tracked fences are completed 79 * (i.e. when the driver is idle), we know that the syncmap is 80 * redundant and we can discard it without loss of generality. 81 */ 82 struct i915_syncmap *sync; 83 84 struct list_head link; 85 struct intel_gt *gt; 86 87 struct list_head engine_link; 88 89 struct kref kref; 90 struct rcu_head rcu; 91 }; 92 93 struct intel_timeline_cacheline { 94 struct i915_active active; 95 96 struct intel_timeline_hwsp *hwsp; 97 void *vaddr; 98 99 u32 ggtt_offset; 100 101 struct rcu_head rcu; 102 }; 103 104 #endif /* __I915_TIMELINE_TYPES_H__ */ 105