/* * Copyright © 2014 Intel Corporation * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice (including the next * paragraph) shall be included in all copies or substantial portions of the * Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS * IN THE SOFTWARE. * * Authors: * Ben Widawsky * Michel Thierry * Thomas Daniel * Oscar Mateo * */ /** * DOC: Logical Rings, Logical Ring Contexts and Execlists * * Motivation: * GEN8 brings an expansion of the HW contexts: "Logical Ring Contexts". * These expanded contexts enable a number of new abilities, especially * "Execlists" (also implemented in this file). * * One of the main differences with the legacy HW contexts is that logical * ring contexts incorporate many more things to the context's state, like * PDPs or ringbuffer control registers: * * The reason why PDPs are included in the context is straightforward: as * PPGTTs (per-process GTTs) are actually per-context, having the PDPs * contained there mean you don't need to do a ppgtt->switch_mm yourself, * instead, the GPU will do it for you on the context switch. * * But, what about the ringbuffer control registers (head, tail, etc..)? * shouldn't we just need a set of those per engine command streamer? This is * where the name "Logical Rings" starts to make sense: by virtualizing the * rings, the engine cs shifts to a new "ring buffer" with every context * switch. When you want to submit a workload to the GPU you: A) choose your * context, B) find its appropriate virtualized ring, C) write commands to it * and then, finally, D) tell the GPU to switch to that context. * * Instead of the legacy MI_SET_CONTEXT, the way you tell the GPU to switch * to a contexts is via a context execution list, ergo "Execlists". * * LRC implementation: * Regarding the creation of contexts, we have: * * - One global default context. * - One local default context for each opened fd. * - One local extra context for each context create ioctl call. * * Now that ringbuffers belong per-context (and not per-engine, like before) * and that contexts are uniquely tied to a given engine (and not reusable, * like before) we need: * * - One ringbuffer per-engine inside each context. * - One backing object per-engine inside each context. * * The global default context starts its life with these new objects fully * allocated and populated. The local default context for each opened fd is * more complex, because we don't know at creation time which engine is going * to use them. To handle this, we have implemented a deferred creation of LR * contexts: * * The local context starts its life as a hollow or blank holder, that only * gets populated for a given engine once we receive an execbuffer. If later * on we receive another execbuffer ioctl for the same context but a different * engine, we allocate/populate a new ringbuffer and context backing object and * so on. * * Finally, regarding local contexts created using the ioctl call: as they are * only allowed with the render ring, we can allocate & populate them right * away (no need to defer anything, at least for now). * * Execlists implementation: * Execlists are the new method by which, on gen8+ hardware, workloads are * submitted for execution (as opposed to the legacy, ringbuffer-based, method). * This method works as follows: * * When a request is committed, its commands (the BB start and any leading or * trailing commands, like the seqno breadcrumbs) are placed in the ringbuffer * for the appropriate context. The tail pointer in the hardware context is not * updated at this time, but instead, kept by the driver in the ringbuffer * structure. A structure representing this request is added to a request queue * for the appropriate engine: this structure contains a copy of the context's * tail after the request was written to the ring buffer and a pointer to the * context itself. * * If the engine's request queue was empty before the request was added, the * queue is processed immediately. Otherwise the queue will be processed during * a context switch interrupt. In any case, elements on the queue will get sent * (in pairs) to the GPU's ExecLists Submit Port (ELSP, for short) with a * globally unique 20-bits submission ID. * * When execution of a request completes, the GPU updates the context status * buffer with a context complete event and generates a context switch interrupt. * During the interrupt handling, the driver examines the events in the buffer: * for each context complete event, if the announced ID matches that on the head * of the request queue, then that request is retired and removed from the queue. * * After processing, if any requests were retired and the queue is not empty * then a new execution list can be submitted. The two requests at the front of * the queue are next to be submitted but since a context may not occur twice in * an execution list, if subsequent requests have the same ID as the first then * the two requests must be combined. This is done simply by discarding requests * at the head of the queue until either only one requests is left (in which case * we use a NULL second context) or the first two requests have unique IDs. * * By always executing the first two requests in the queue the driver ensures * that the GPU is kept as busy as possible. In the case where a single context * completes but a second context is still executing, the request for this second * context will be at the head of the queue when we remove the first one. This * request will then be resubmitted along with a new request for a different context, * which will cause the hardware to continue executing the second request and queue * the new request (the GPU detects the condition of a context getting preempted * with the same context and optimizes the context switch flow by not doing * preemption, but just sampling the new tail pointer). * */ #include #include #include "i915_drv.h" #include "i915_gem_render_state.h" #include "i915_reset.h" #include "i915_vgpu.h" #include "intel_lrc_reg.h" #include "intel_mocs.h" #include "intel_workarounds.h" #define RING_EXECLIST_QFULL (1 << 0x2) #define RING_EXECLIST1_VALID (1 << 0x3) #define RING_EXECLIST0_VALID (1 << 0x4) #define RING_EXECLIST_ACTIVE_STATUS (3 << 0xE) #define RING_EXECLIST1_ACTIVE (1 << 0x11) #define RING_EXECLIST0_ACTIVE (1 << 0x12) #define GEN8_CTX_STATUS_IDLE_ACTIVE (1 << 0) #define GEN8_CTX_STATUS_PREEMPTED (1 << 1) #define GEN8_CTX_STATUS_ELEMENT_SWITCH (1 << 2) #define GEN8_CTX_STATUS_ACTIVE_IDLE (1 << 3) #define GEN8_CTX_STATUS_COMPLETE (1 << 4) #define GEN8_CTX_STATUS_LITE_RESTORE (1 << 15) #define GEN8_CTX_STATUS_COMPLETED_MASK \ (GEN8_CTX_STATUS_COMPLETE | GEN8_CTX_STATUS_PREEMPTED) /* Typical size of the average request (2 pipecontrols and a MI_BB) */ #define EXECLISTS_REQUEST_SIZE 64 /* bytes */ #define WA_TAIL_DWORDS 2 #define WA_TAIL_BYTES (sizeof(u32) * WA_TAIL_DWORDS) static int execlists_context_deferred_alloc(struct i915_gem_context *ctx, struct intel_engine_cs *engine, struct intel_context *ce); static void execlists_init_reg_state(u32 *reg_state, struct i915_gem_context *ctx, struct intel_engine_cs *engine, struct intel_ring *ring); static inline u32 intel_hws_seqno_address(struct intel_engine_cs *engine) { return (i915_ggtt_offset(engine->status_page.vma) + I915_GEM_HWS_INDEX_ADDR); } static inline struct i915_priolist *to_priolist(struct rb_node *rb) { return rb_entry(rb, struct i915_priolist, node); } static inline int rq_prio(const struct i915_request *rq) { return rq->sched.attr.priority; } static int queue_prio(const struct intel_engine_execlists *execlists) { struct i915_priolist *p; struct rb_node *rb; rb = rb_first_cached(&execlists->queue); if (!rb) return INT_MIN; /* * As the priolist[] are inverted, with the highest priority in [0], * we have to flip the index value to become priority. */ p = to_priolist(rb); return ((p->priority + 1) << I915_USER_PRIORITY_SHIFT) - ffs(p->used); } static inline bool need_preempt(const struct intel_engine_cs *engine, const struct i915_request *rq) { const int last_prio = rq_prio(rq); if (!intel_engine_has_preemption(engine)) return false; if (i915_request_completed(rq)) return false; /* * Check if the current priority hint merits a preemption attempt. * * We record the highest value priority we saw during rescheduling * prior to this dequeue, therefore we know that if it is strictly * less than the current tail of ESLP[0], we do not need to force * a preempt-to-idle cycle. * * However, the priority hint is a mere hint that we may need to * preempt. If that hint is stale or we may be trying to preempt * ourselves, ignore the request. */ if (!__execlists_need_preempt(engine->execlists.queue_priority_hint, last_prio)) return false; /* * Check against the first request in ELSP[1], it will, thanks to the * power of PI, be the highest priority of that context. */ if (!list_is_last(&rq->link, &engine->timeline.requests) && rq_prio(list_next_entry(rq, link)) > last_prio) return true; /* * If the inflight context did not trigger the preemption, then maybe * it was the set of queued requests? Pick the highest priority in * the queue (the first active priolist) and see if it deserves to be * running instead of ELSP[0]. * * The highest priority request in the queue can not be either * ELSP[0] or ELSP[1] as, thanks again to PI, if it was the same * context, it's priority would not exceed ELSP[0] aka last_prio. */ return queue_prio(&engine->execlists) > last_prio; } __maybe_unused static inline bool assert_priority_queue(const struct intel_engine_execlists *execlists, const struct i915_request *prev, const struct i915_request *next) { if (!prev) return true; /* * Without preemption, the prev may refer to the still active element * which we refuse to let go. * * Even with preemption, there are times when we think it is better not * to preempt and leave an ostensibly lower priority request in flight. */ if (port_request(execlists->port) == prev) return true; return rq_prio(prev) >= rq_prio(next); } /* * The context descriptor encodes various attributes of a context, * including its GTT address and some flags. Because it's fairly * expensive to calculate, we'll just do it once and cache the result, * which remains valid until the context is unpinned. * * This is what a descriptor looks like, from LSB to MSB:: * * bits 0-11: flags, GEN8_CTX_* (cached in ctx->desc_template) * bits 12-31: LRCA, GTT address of (the HWSP of) this context * bits 32-52: ctx ID, a globally unique tag (highest bit used by GuC) * bits 53-54: mbz, reserved for use by hardware * bits 55-63: group ID, currently unused and set to 0 * * Starting from Gen11, the upper dword of the descriptor has a new format: * * bits 32-36: reserved * bits 37-47: SW context ID * bits 48:53: engine instance * bit 54: mbz, reserved for use by hardware * bits 55-60: SW counter * bits 61-63: engine class * * engine info, SW context ID and SW counter need to form a unique number * (Context ID) per lrc. */ static void intel_lr_context_descriptor_update(struct i915_gem_context *ctx, struct intel_engine_cs *engine, struct intel_context *ce) { u64 desc; BUILD_BUG_ON(MAX_CONTEXT_HW_ID > (BIT(GEN8_CTX_ID_WIDTH))); BUILD_BUG_ON(GEN11_MAX_CONTEXT_HW_ID > (BIT(GEN11_SW_CTX_ID_WIDTH))); desc = ctx->desc_template; /* bits 0-11 */ GEM_BUG_ON(desc & GENMASK_ULL(63, 12)); desc |= i915_ggtt_offset(ce->state) + LRC_HEADER_PAGES * PAGE_SIZE; /* bits 12-31 */ GEM_BUG_ON(desc & GENMASK_ULL(63, 32)); /* * The following 32bits are copied into the OA reports (dword 2). * Consider updating oa_get_render_ctx_id in i915_perf.c when changing * anything below. */ if (INTEL_GEN(ctx->i915) >= 11) { GEM_BUG_ON(ctx->hw_id >= BIT(GEN11_SW_CTX_ID_WIDTH)); desc |= (u64)ctx->hw_id << GEN11_SW_CTX_ID_SHIFT; /* bits 37-47 */ desc |= (u64)engine->instance << GEN11_ENGINE_INSTANCE_SHIFT; /* bits 48-53 */ /* TODO: decide what to do with SW counter (bits 55-60) */ desc |= (u64)engine->class << GEN11_ENGINE_CLASS_SHIFT; /* bits 61-63 */ } else { GEM_BUG_ON(ctx->hw_id >= BIT(GEN8_CTX_ID_WIDTH)); desc |= (u64)ctx->hw_id << GEN8_CTX_ID_SHIFT; /* bits 32-52 */ } ce->lrc_desc = desc; } static void unwind_wa_tail(struct i915_request *rq) { rq->tail = intel_ring_wrap(rq->ring, rq->wa_tail - WA_TAIL_BYTES); assert_ring_tail_valid(rq->ring, rq->tail); } static struct i915_request * __unwind_incomplete_requests(struct intel_engine_cs *engine) { struct i915_request *rq, *rn, *active = NULL; struct list_head *uninitialized_var(pl); int prio = I915_PRIORITY_INVALID | I915_PRIORITY_NEWCLIENT; lockdep_assert_held(&engine->timeline.lock); list_for_each_entry_safe_reverse(rq, rn, &engine->timeline.requests, link) { if (i915_request_completed(rq)) break; __i915_request_unsubmit(rq); unwind_wa_tail(rq); GEM_BUG_ON(rq->hw_context->active); GEM_BUG_ON(rq_prio(rq) == I915_PRIORITY_INVALID); if (rq_prio(rq) != prio) { prio = rq_prio(rq); pl = i915_sched_lookup_priolist(engine, prio); } GEM_BUG_ON(RB_EMPTY_ROOT(&engine->execlists.queue.rb_root)); list_add(&rq->sched.link, pl); active = rq; } /* * The active request is now effectively the start of a new client * stream, so give it the equivalent small priority bump to prevent * it being gazumped a second time by another peer. */ if (!(prio & I915_PRIORITY_NEWCLIENT)) { prio |= I915_PRIORITY_NEWCLIENT; active->sched.attr.priority = prio; list_move_tail(&active->sched.link, i915_sched_lookup_priolist(engine, prio)); } return active; } void execlists_unwind_incomplete_requests(struct intel_engine_execlists *execlists) { struct intel_engine_cs *engine = container_of(execlists, typeof(*engine), execlists); __unwind_incomplete_requests(engine); } static inline void execlists_context_status_change(struct i915_request *rq, unsigned long status) { /* * Only used when GVT-g is enabled now. When GVT-g is disabled, * The compiler should eliminate this function as dead-code. */ if (!IS_ENABLED(CONFIG_DRM_I915_GVT)) return; atomic_notifier_call_chain(&rq->engine->context_status_notifier, status, rq); } inline void execlists_user_begin(struct intel_engine_execlists *execlists, const struct execlist_port *port) { execlists_set_active_once(execlists, EXECLISTS_ACTIVE_USER); } inline void execlists_user_end(struct intel_engine_execlists *execlists) { execlists_clear_active(execlists, EXECLISTS_ACTIVE_USER); } static inline void execlists_context_schedule_in(struct i915_request *rq) { GEM_BUG_ON(rq->hw_context->active); execlists_context_status_change(rq, INTEL_CONTEXT_SCHEDULE_IN); intel_engine_context_in(rq->engine); rq->hw_context->active = rq->engine; } static inline void execlists_context_schedule_out(struct i915_request *rq, unsigned long status) { rq->hw_context->active = NULL; intel_engine_context_out(rq->engine); execlists_context_status_change(rq, status); trace_i915_request_out(rq); } static u64 execlists_update_context(struct i915_request *rq) { struct intel_context *ce = rq->hw_context; ce->lrc_reg_state[CTX_RING_TAIL + 1] = intel_ring_set_tail(rq->ring, rq->tail); /* * Make sure the context image is complete before we submit it to HW. * * Ostensibly, writes (including the WCB) should be flushed prior to * an uncached write such as our mmio register access, the empirical * evidence (esp. on Braswell) suggests that the WC write into memory * may not be visible to the HW prior to the completion of the UC * register write and that we may begin execution from the context * before its image is complete leading to invalid PD chasing. * * Furthermore, Braswell, at least, wants a full mb to be sure that * the writes are coherent in memory (visible to the GPU) prior to * execution, and not just visible to other CPUs (as is the result of * wmb). */ mb(); return ce->lrc_desc; } static inline void write_desc(struct intel_engine_execlists *execlists, u64 desc, u32 port) { if (execlists->ctrl_reg) { writel(lower_32_bits(desc), execlists->submit_reg + port * 2); writel(upper_32_bits(desc), execlists->submit_reg + port * 2 + 1); } else { writel(upper_32_bits(desc), execlists->submit_reg); writel(lower_32_bits(desc), execlists->submit_reg); } } static void execlists_submit_ports(struct intel_engine_cs *engine) { struct intel_engine_execlists *execlists = &engine->execlists; struct execlist_port *port = execlists->port; unsigned int n; /* * We can skip acquiring intel_runtime_pm_get() here as it was taken * on our behalf by the request (see i915_gem_mark_busy()) and it will * not be relinquished until the device is idle (see * i915_gem_idle_work_handler()). As a precaution, we make sure * that all ELSP are drained i.e. we have processed the CSB, * before allowing ourselves to idle and calling intel_runtime_pm_put(). */ GEM_BUG_ON(!engine->i915->gt.awake); /* * ELSQ note: the submit queue is not cleared after being submitted * to the HW so we need to make sure we always clean it up. This is * currently ensured by the fact that we always write the same number * of elsq entries, keep this in mind before changing the loop below. */ for (n = execlists_num_ports(execlists); n--; ) { struct i915_request *rq; unsigned int count; u64 desc; rq = port_unpack(&port[n], &count); if (rq) { GEM_BUG_ON(count > !n); if (!count++) execlists_context_schedule_in(rq); port_set(&port[n], port_pack(rq, count)); desc = execlists_update_context(rq); GEM_DEBUG_EXEC(port[n].context_id = upper_32_bits(desc)); GEM_TRACE("%s in[%d]: ctx=%d.%d, global=%d (fence %llx:%lld) (current %d:%d), prio=%d\n", engine->name, n, port[n].context_id, count, rq->global_seqno, rq->fence.context, rq->fence.seqno, hwsp_seqno(rq), intel_engine_get_seqno(engine), rq_prio(rq)); } else { GEM_BUG_ON(!n); desc = 0; } write_desc(execlists, desc, n); } /* we need to manually load the submit queue */ if (execlists->ctrl_reg) writel(EL_CTRL_LOAD, execlists->ctrl_reg); execlists_clear_active(execlists, EXECLISTS_ACTIVE_HWACK); } static bool ctx_single_port_submission(const struct intel_context *ce) { return (IS_ENABLED(CONFIG_DRM_I915_GVT) && i915_gem_context_force_single_submission(ce->gem_context)); } static bool can_merge_ctx(const struct intel_context *prev, const struct intel_context *next) { if (prev != next) return false; if (ctx_single_port_submission(prev)) return false; return true; } static void port_assign(struct execlist_port *port, struct i915_request *rq) { GEM_BUG_ON(rq == port_request(port)); if (port_isset(port)) i915_request_put(port_request(port)); port_set(port, port_pack(i915_request_get(rq), port_count(port))); } static void inject_preempt_context(struct intel_engine_cs *engine) { struct intel_engine_execlists *execlists = &engine->execlists; struct intel_context *ce = to_intel_context(engine->i915->preempt_context, engine); unsigned int n; GEM_BUG_ON(execlists->preempt_complete_status != upper_32_bits(ce->lrc_desc)); /* * Switch to our empty preempt context so * the state of the GPU is known (idle). */ GEM_TRACE("%s\n", engine->name); for (n = execlists_num_ports(execlists); --n; ) write_desc(execlists, 0, n); write_desc(execlists, ce->lrc_desc, n); /* we need to manually load the submit queue */ if (execlists->ctrl_reg) writel(EL_CTRL_LOAD, execlists->ctrl_reg); execlists_clear_active(execlists, EXECLISTS_ACTIVE_HWACK); execlists_set_active(execlists, EXECLISTS_ACTIVE_PREEMPT); (void)I915_SELFTEST_ONLY(execlists->preempt_hang.count++); } static void complete_preempt_context(struct intel_engine_execlists *execlists) { GEM_BUG_ON(!execlists_is_active(execlists, EXECLISTS_ACTIVE_PREEMPT)); if (inject_preempt_hang(execlists)) return; execlists_cancel_port_requests(execlists); __unwind_incomplete_requests(container_of(execlists, struct intel_engine_cs, execlists)); } static void execlists_dequeue(struct intel_engine_cs *engine) { struct intel_engine_execlists * const execlists = &engine->execlists; struct execlist_port *port = execlists->port; const struct execlist_port * const last_port = &execlists->port[execlists->port_mask]; struct i915_request *last = port_request(port); struct rb_node *rb; bool submit = false; /* * Hardware submission is through 2 ports. Conceptually each port * has a (RING_START, RING_HEAD, RING_TAIL) tuple. RING_START is * static for a context, and unique to each, so we only execute * requests belonging to a single context from each ring. RING_HEAD * is maintained by the CS in the context image, it marks the place * where it got up to last time, and through RING_TAIL we tell the CS * where we want to execute up to this time. * * In this list the requests are in order of execution. Consecutive * requests from the same context are adjacent in the ringbuffer. We * can combine these requests into a single RING_TAIL update: * * RING_HEAD...req1...req2 * ^- RING_TAIL * since to execute req2 the CS must first execute req1. * * Our goal then is to point each port to the end of a consecutive * sequence of requests as being the most optimal (fewest wake ups * and context switches) submission. */ if (last) { /* * Don't resubmit or switch until all outstanding * preemptions (lite-restore) are seen. Then we * know the next preemption status we see corresponds * to this ELSP update. */ GEM_BUG_ON(!execlists_is_active(execlists, EXECLISTS_ACTIVE_USER)); GEM_BUG_ON(!port_count(&port[0])); /* * If we write to ELSP a second time before the HW has had * a chance to respond to the previous write, we can confuse * the HW and hit "undefined behaviour". After writing to ELSP, * we must then wait until we see a context-switch event from * the HW to indicate that it has had a chance to respond. */ if (!execlists_is_active(execlists, EXECLISTS_ACTIVE_HWACK)) return; if (need_preempt(engine, last)) { inject_preempt_context(engine); return; } /* * In theory, we could coalesce more requests onto * the second port (the first port is active, with * no preemptions pending). However, that means we * then have to deal with the possible lite-restore * of the second port (as we submit the ELSP, there * may be a context-switch) but also we may complete * the resubmission before the context-switch. Ergo, * coalescing onto the second port will cause a * preemption event, but we cannot predict whether * that will affect port[0] or port[1]. * * If the second port is already active, we can wait * until the next context-switch before contemplating * new requests. The GPU will be busy and we should be * able to resubmit the new ELSP before it idles, * avoiding pipeline bubbles (momentary pauses where * the driver is unable to keep up the supply of new * work). However, we have to double check that the * priorities of the ports haven't been switch. */ if (port_count(&port[1])) return; /* * WaIdleLiteRestore:bdw,skl * Apply the wa NOOPs to prevent * ring:HEAD == rq:TAIL as we resubmit the * request. See gen8_emit_fini_breadcrumb() for * where we prepare the padding after the * end of the request. */ last->tail = last->wa_tail; } while ((rb = rb_first_cached(&execlists->queue))) { struct i915_priolist *p = to_priolist(rb); struct i915_request *rq, *rn; int i; priolist_for_each_request_consume(rq, rn, p, i) { GEM_BUG_ON(!assert_priority_queue(execlists, last, rq)); /* * Can we combine this request with the current port? * It has to be the same context/ringbuffer and not * have any exceptions (e.g. GVT saying never to * combine contexts). * * If we can combine the requests, we can execute both * by updating the RING_TAIL to point to the end of the * second request, and so we never need to tell the * hardware about the first. */ if (last && !can_merge_ctx(rq->hw_context, last->hw_context)) { /* * If we are on the second port and cannot * combine this request with the last, then we * are done. */ if (port == last_port) goto done; /* * If GVT overrides us we only ever submit * port[0], leaving port[1] empty. Note that we * also have to be careful that we don't queue * the same context (even though a different * request) to the second port. */ if (ctx_single_port_submission(last->hw_context) || ctx_single_port_submission(rq->hw_context)) goto done; GEM_BUG_ON(last->hw_context == rq->hw_context); if (submit) port_assign(port, last); port++; GEM_BUG_ON(port_isset(port)); } list_del_init(&rq->sched.link); __i915_request_submit(rq); trace_i915_request_in(rq, port_index(port, execlists)); last = rq; submit = true; } rb_erase_cached(&p->node, &execlists->queue); if (p->priority != I915_PRIORITY_NORMAL) kmem_cache_free(engine->i915->priorities, p); } done: /* * Here be a bit of magic! Or sleight-of-hand, whichever you prefer. * * We choose the priority hint such that if we add a request of greater * priority than this, we kick the submission tasklet to decide on * the right order of submitting the requests to hardware. We must * also be prepared to reorder requests as they are in-flight on the * HW. We derive the priority hint then as the first "hole" in * the HW submission ports and if there are no available slots, * the priority of the lowest executing request, i.e. last. * * When we do receive a higher priority request ready to run from the * user, see queue_request(), the priority hint is bumped to that * request triggering preemption on the next dequeue (or subsequent * interrupt for secondary ports). */ execlists->queue_priority_hint = port != execlists->port ? rq_prio(last) : INT_MIN; if (submit) { port_assign(port, last); execlists_submit_ports(engine); } /* We must always keep the beast fed if we have work piled up */ GEM_BUG_ON(rb_first_cached(&execlists->queue) && !port_isset(execlists->port)); /* Re-evaluate the executing context setup after each preemptive kick */ if (last) execlists_user_begin(execlists, execlists->port); /* If the engine is now idle, so should be the flag; and vice versa. */ GEM_BUG_ON(execlists_is_active(&engine->execlists, EXECLISTS_ACTIVE_USER) == !port_isset(engine->execlists.port)); } void execlists_cancel_port_requests(struct intel_engine_execlists * const execlists) { struct execlist_port *port = execlists->port; unsigned int num_ports = execlists_num_ports(execlists); while (num_ports-- && port_isset(port)) { struct i915_request *rq = port_request(port); GEM_TRACE("%s:port%u global=%d (fence %llx:%lld), (current %d:%d)\n", rq->engine->name, (unsigned int)(port - execlists->port), rq->global_seqno, rq->fence.context, rq->fence.seqno, hwsp_seqno(rq), intel_engine_get_seqno(rq->engine)); GEM_BUG_ON(!execlists->active); execlists_context_schedule_out(rq, i915_request_completed(rq) ? INTEL_CONTEXT_SCHEDULE_OUT : INTEL_CONTEXT_SCHEDULE_PREEMPTED); i915_request_put(rq); memset(port, 0, sizeof(*port)); port++; } execlists_clear_all_active(execlists); } static inline void invalidate_csb_entries(const u32 *first, const u32 *last) { clflush((void *)first); clflush((void *)last); } static void reset_csb_pointers(struct intel_engine_execlists *execlists) { const unsigned int reset_value = GEN8_CSB_ENTRIES - 1; /* * After a reset, the HW starts writing into CSB entry [0]. We * therefore have to set our HEAD pointer back one entry so that * the *first* entry we check is entry 0. To complicate this further, * as we don't wait for the first interrupt after reset, we have to * fake the HW write to point back to the last entry so that our * inline comparison of our cached head position against the last HW * write works even before the first interrupt. */ execlists->csb_head = reset_value; WRITE_ONCE(*execlists->csb_write, reset_value); invalidate_csb_entries(&execlists->csb_status[0], &execlists->csb_status[GEN8_CSB_ENTRIES - 1]); } static void nop_submission_tasklet(unsigned long data) { /* The driver is wedged; don't process any more events. */ } static void execlists_cancel_requests(struct intel_engine_cs *engine) { struct intel_engine_execlists * const execlists = &engine->execlists; struct i915_request *rq, *rn; struct rb_node *rb; unsigned long flags; GEM_TRACE("%s current %d\n", engine->name, intel_engine_get_seqno(engine)); /* * Before we call engine->cancel_requests(), we should have exclusive * access to the submission state. This is arranged for us by the * caller disabling the interrupt generation, the tasklet and other * threads that may then access the same state, giving us a free hand * to reset state. However, we still need to let lockdep be aware that * we know this state may be accessed in hardirq context, so we * disable the irq around this manipulation and we want to keep * the spinlock focused on its duties and not accidentally conflate * coverage to the submission's irq state. (Similarly, although we * shouldn't need to disable irq around the manipulation of the * submission's irq state, we also wish to remind ourselves that * it is irq state.) */ spin_lock_irqsave(&engine->timeline.lock, flags); /* Cancel the requests on the HW and clear the ELSP tracker. */ execlists_cancel_port_requests(execlists); execlists_user_end(execlists); /* Mark all executing requests as skipped. */ list_for_each_entry(rq, &engine->timeline.requests, link) { GEM_BUG_ON(!rq->global_seqno); if (!i915_request_signaled(rq)) dma_fence_set_error(&rq->fence, -EIO); i915_request_mark_complete(rq); } /* Flush the queued requests to the timeline list (for retiring). */ while ((rb = rb_first_cached(&execlists->queue))) { struct i915_priolist *p = to_priolist(rb); int i; priolist_for_each_request_consume(rq, rn, p, i) { list_del_init(&rq->sched.link); __i915_request_submit(rq); dma_fence_set_error(&rq->fence, -EIO); i915_request_mark_complete(rq); } rb_erase_cached(&p->node, &execlists->queue); if (p->priority != I915_PRIORITY_NORMAL) kmem_cache_free(engine->i915->priorities, p); } intel_write_status_page(engine, I915_GEM_HWS_INDEX, intel_engine_last_submit(engine)); /* Remaining _unready_ requests will be nop'ed when submitted */ execlists->queue_priority_hint = INT_MIN; execlists->queue = RB_ROOT_CACHED; GEM_BUG_ON(port_isset(execlists->port)); GEM_BUG_ON(__tasklet_is_enabled(&execlists->tasklet)); execlists->tasklet.func = nop_submission_tasklet; spin_unlock_irqrestore(&engine->timeline.lock, flags); } static inline bool reset_in_progress(const struct intel_engine_execlists *execlists) { return unlikely(!__tasklet_is_enabled(&execlists->tasklet)); } static void process_csb(struct intel_engine_cs *engine) { struct intel_engine_execlists * const execlists = &engine->execlists; struct execlist_port *port = execlists->port; const u32 * const buf = execlists->csb_status; u8 head, tail; lockdep_assert_held(&engine->timeline.lock); /* * Note that csb_write, csb_status may be either in HWSP or mmio. * When reading from the csb_write mmio register, we have to be * careful to only use the GEN8_CSB_WRITE_PTR portion, which is * the low 4bits. As it happens we know the next 4bits are always * zero and so we can simply masked off the low u8 of the register * and treat it identically to reading from the HWSP (without having * to use explicit shifting and masking, and probably bifurcating * the code to handle the legacy mmio read). */ head = execlists->csb_head; tail = READ_ONCE(*execlists->csb_write); GEM_TRACE("%s cs-irq head=%d, tail=%d\n", engine->name, head, tail); if (unlikely(head == tail)) return; /* * Hopefully paired with a wmb() in HW! * * We must complete the read of the write pointer before any reads * from the CSB, so that we do not see stale values. Without an rmb * (lfence) the HW may speculatively perform the CSB[] reads *before* * we perform the READ_ONCE(*csb_write). */ rmb(); do { struct i915_request *rq; unsigned int status; unsigned int count; if (++head == GEN8_CSB_ENTRIES) head = 0; /* * We are flying near dragons again. * * We hold a reference to the request in execlist_port[] * but no more than that. We are operating in softirq * context and so cannot hold any mutex or sleep. That * prevents us stopping the requests we are processing * in port[] from being retired simultaneously (the * breadcrumb will be complete before we see the * context-switch). As we only hold the reference to the * request, any pointer chasing underneath the request * is subject to a potential use-after-free. Thus we * store all of the bookkeeping within port[] as * required, and avoid using unguarded pointers beneath * request itself. The same applies to the atomic * status notifier. */ GEM_TRACE("%s csb[%d]: status=0x%08x:0x%08x, active=0x%x\n", engine->name, head, buf[2 * head + 0], buf[2 * head + 1], execlists->active); status = buf[2 * head]; if (status & (GEN8_CTX_STATUS_IDLE_ACTIVE | GEN8_CTX_STATUS_PREEMPTED)) execlists_set_active(execlists, EXECLISTS_ACTIVE_HWACK); if (status & GEN8_CTX_STATUS_ACTIVE_IDLE) execlists_clear_active(execlists, EXECLISTS_ACTIVE_HWACK); if (!(status & GEN8_CTX_STATUS_COMPLETED_MASK)) continue; /* We should never get a COMPLETED | IDLE_ACTIVE! */ GEM_BUG_ON(status & GEN8_CTX_STATUS_IDLE_ACTIVE); if (status & GEN8_CTX_STATUS_COMPLETE && buf[2*head + 1] == execlists->preempt_complete_status) { GEM_TRACE("%s preempt-idle\n", engine->name); complete_preempt_context(execlists); continue; } if (status & GEN8_CTX_STATUS_PREEMPTED && execlists_is_active(execlists, EXECLISTS_ACTIVE_PREEMPT)) continue; GEM_BUG_ON(!execlists_is_active(execlists, EXECLISTS_ACTIVE_USER)); rq = port_unpack(port, &count); GEM_TRACE("%s out[0]: ctx=%d.%d, global=%d (fence %llx:%lld) (current %d:%d), prio=%d\n", engine->name, port->context_id, count, rq ? rq->global_seqno : 0, rq ? rq->fence.context : 0, rq ? rq->fence.seqno : 0, rq ? hwsp_seqno(rq) : 0, intel_engine_get_seqno(engine), rq ? rq_prio(rq) : 0); /* Check the context/desc id for this event matches */ GEM_DEBUG_BUG_ON(buf[2 * head + 1] != port->context_id); GEM_BUG_ON(count == 0); if (--count == 0) { /* * On the final event corresponding to the * submission of this context, we expect either * an element-switch event or a completion * event (and on completion, the active-idle * marker). No more preemptions, lite-restore * or otherwise. */ GEM_BUG_ON(status & GEN8_CTX_STATUS_PREEMPTED); GEM_BUG_ON(port_isset(&port[1]) && !(status & GEN8_CTX_STATUS_ELEMENT_SWITCH)); GEM_BUG_ON(!port_isset(&port[1]) && !(status & GEN8_CTX_STATUS_ACTIVE_IDLE)); /* * We rely on the hardware being strongly * ordered, that the breadcrumb write is * coherent (visible from the CPU) before the * user interrupt and CSB is processed. */ GEM_BUG_ON(!i915_request_completed(rq)); execlists_context_schedule_out(rq, INTEL_CONTEXT_SCHEDULE_OUT); i915_request_put(rq); GEM_TRACE("%s completed ctx=%d\n", engine->name, port->context_id); port = execlists_port_complete(execlists, port); if (port_isset(port)) execlists_user_begin(execlists, port); else execlists_user_end(execlists); } else { port_set(port, port_pack(rq, count)); } } while (head != tail); execlists->csb_head = head; /* * Gen11 has proven to fail wrt global observation point between * entry and tail update, failing on the ordering and thus * we see an old entry in the context status buffer. * * Forcibly evict out entries for the next gpu csb update, * to increase the odds that we get a fresh entries with non * working hardware. The cost for doing so comes out mostly with * the wash as hardware, working or not, will need to do the * invalidation before. */ invalidate_csb_entries(&buf[0], &buf[GEN8_CSB_ENTRIES - 1]); } static void __execlists_submission_tasklet(struct intel_engine_cs *const engine) { lockdep_assert_held(&engine->timeline.lock); process_csb(engine); if (!execlists_is_active(&engine->execlists, EXECLISTS_ACTIVE_PREEMPT)) execlists_dequeue(engine); } /* * Check the unread Context Status Buffers and manage the submission of new * contexts to the ELSP accordingly. */ static void execlists_submission_tasklet(unsigned long data) { struct intel_engine_cs * const engine = (struct intel_engine_cs *)data; unsigned long flags; GEM_TRACE("%s awake?=%d, active=%x\n", engine->name, !!engine->i915->gt.awake, engine->execlists.active); spin_lock_irqsave(&engine->timeline.lock, flags); __execlists_submission_tasklet(engine); spin_unlock_irqrestore(&engine->timeline.lock, flags); } static void queue_request(struct intel_engine_cs *engine, struct i915_sched_node *node, int prio) { list_add_tail(&node->link, i915_sched_lookup_priolist(engine, prio)); } static void __submit_queue_imm(struct intel_engine_cs *engine) { struct intel_engine_execlists * const execlists = &engine->execlists; if (reset_in_progress(execlists)) return; /* defer until we restart the engine following reset */ if (execlists->tasklet.func == execlists_submission_tasklet) __execlists_submission_tasklet(engine); else tasklet_hi_schedule(&execlists->tasklet); } static void submit_queue(struct intel_engine_cs *engine, int prio) { if (prio > engine->execlists.queue_priority_hint) { engine->execlists.queue_priority_hint = prio; __submit_queue_imm(engine); } } static void execlists_submit_request(struct i915_request *request) { struct intel_engine_cs *engine = request->engine; unsigned long flags; /* Will be called from irq-context when using foreign fences. */ spin_lock_irqsave(&engine->timeline.lock, flags); queue_request(engine, &request->sched, rq_prio(request)); GEM_BUG_ON(RB_EMPTY_ROOT(&engine->execlists.queue.rb_root)); GEM_BUG_ON(list_empty(&request->sched.link)); submit_queue(engine, rq_prio(request)); spin_unlock_irqrestore(&engine->timeline.lock, flags); } static void execlists_context_destroy(struct intel_context *ce) { GEM_BUG_ON(ce->pin_count); if (!ce->state) return; intel_ring_free(ce->ring); GEM_BUG_ON(i915_gem_object_is_active(ce->state->obj)); i915_gem_object_put(ce->state->obj); } static void execlists_context_unpin(struct intel_context *ce) { struct intel_engine_cs *engine; /* * The tasklet may still be using a pointer to our state, via an * old request. However, since we know we only unpin the context * on retirement of the following request, we know that the last * request referencing us will have had a completion CS interrupt. * If we see that it is still active, it means that the tasklet hasn't * had the chance to run yet; let it run before we teardown the * reference it may use. */ engine = READ_ONCE(ce->active); if (unlikely(engine)) { unsigned long flags; spin_lock_irqsave(&engine->timeline.lock, flags); process_csb(engine); spin_unlock_irqrestore(&engine->timeline.lock, flags); GEM_BUG_ON(READ_ONCE(ce->active)); } i915_gem_context_unpin_hw_id(ce->gem_context); intel_ring_unpin(ce->ring); ce->state->obj->pin_global--; i915_gem_object_unpin_map(ce->state->obj); i915_vma_unpin(ce->state); i915_gem_context_put(ce->gem_context); } static int __context_pin(struct i915_gem_context *ctx, struct i915_vma *vma) { unsigned int flags; int err; /* * Clear this page out of any CPU caches for coherent swap-in/out. * We only want to do this on the first bind so that we do not stall * on an active context (which by nature is already on the GPU). */ if (!(vma->flags & I915_VMA_GLOBAL_BIND)) { err = i915_gem_object_set_to_wc_domain(vma->obj, true); if (err) return err; } flags = PIN_GLOBAL | PIN_HIGH; flags |= PIN_OFFSET_BIAS | i915_ggtt_pin_bias(vma); return i915_vma_pin(vma, 0, 0, flags); } static u32 make_rpcs(struct drm_i915_private *dev_priv); static void __execlists_update_reg_state(struct intel_engine_cs *engine, struct intel_context *ce) { u32 *regs = ce->lrc_reg_state; struct intel_ring *ring = ce->ring; regs[CTX_RING_BUFFER_START + 1] = i915_ggtt_offset(ring->vma); regs[CTX_RING_HEAD + 1] = ring->head; regs[CTX_RING_TAIL + 1] = ring->tail; /* RPCS */ if (engine->class == RENDER_CLASS) regs[CTX_R_PWR_CLK_STATE + 1] = make_rpcs(engine->i915); } static struct intel_context * __execlists_context_pin(struct intel_engine_cs *engine, struct i915_gem_context *ctx, struct intel_context *ce) { void *vaddr; int ret; ret = execlists_context_deferred_alloc(ctx, engine, ce); if (ret) goto err; GEM_BUG_ON(!ce->state); ret = __context_pin(ctx, ce->state); if (ret) goto err; vaddr = i915_gem_object_pin_map(ce->state->obj, i915_coherent_map_type(ctx->i915) | I915_MAP_OVERRIDE); if (IS_ERR(vaddr)) { ret = PTR_ERR(vaddr); goto unpin_vma; } ret = intel_ring_pin(ce->ring); if (ret) goto unpin_map; ret = i915_gem_context_pin_hw_id(ctx); if (ret) goto unpin_ring; intel_lr_context_descriptor_update(ctx, engine, ce); GEM_BUG_ON(!intel_ring_offset_valid(ce->ring, ce->ring->head)); ce->lrc_reg_state = vaddr + LRC_STATE_PN * PAGE_SIZE; __execlists_update_reg_state(engine, ce); ce->state->obj->pin_global++; i915_gem_context_get(ctx); return ce; unpin_ring: intel_ring_unpin(ce->ring); unpin_map: i915_gem_object_unpin_map(ce->state->obj); unpin_vma: __i915_vma_unpin(ce->state); err: ce->pin_count = 0; return ERR_PTR(ret); } static const struct intel_context_ops execlists_context_ops = { .unpin = execlists_context_unpin, .destroy = execlists_context_destroy, }; static struct intel_context * execlists_context_pin(struct intel_engine_cs *engine, struct i915_gem_context *ctx) { struct intel_context *ce = to_intel_context(ctx, engine); lockdep_assert_held(&ctx->i915->drm.struct_mutex); GEM_BUG_ON(!ctx->ppgtt); if (likely(ce->pin_count++)) return ce; GEM_BUG_ON(!ce->pin_count); /* no overflow please! */ ce->ops = &execlists_context_ops; return __execlists_context_pin(engine, ctx, ce); } static int gen8_emit_init_breadcrumb(struct i915_request *rq) { u32 *cs; GEM_BUG_ON(!rq->timeline->has_initial_breadcrumb); cs = intel_ring_begin(rq, 6); if (IS_ERR(cs)) return PTR_ERR(cs); /* * Check if we have been preempted before we even get started. * * After this point i915_request_started() reports true, even if * we get preempted and so are no longer running. */ *cs++ = MI_ARB_CHECK; *cs++ = MI_NOOP; *cs++ = MI_STORE_DWORD_IMM_GEN4 | MI_USE_GGTT; *cs++ = rq->timeline->hwsp_offset; *cs++ = 0; *cs++ = rq->fence.seqno - 1; intel_ring_advance(rq, cs); return 0; } static int emit_pdps(struct i915_request *rq) { const struct intel_engine_cs * const engine = rq->engine; struct i915_hw_ppgtt * const ppgtt = rq->gem_context->ppgtt; int err, i; u32 *cs; GEM_BUG_ON(intel_vgpu_active(rq->i915)); /* * Beware ye of the dragons, this sequence is magic! * * Small changes to this sequence can cause anything from * GPU hangs to forcewake errors and machine lockups! */ /* Flush any residual operations from the context load */ err = engine->emit_flush(rq, EMIT_FLUSH); if (err) return err; /* Magic required to prevent forcewake errors! */ err = engine->emit_flush(rq, EMIT_INVALIDATE); if (err) return err; cs = intel_ring_begin(rq, 4 * GEN8_3LVL_PDPES + 2); if (IS_ERR(cs)) return PTR_ERR(cs); /* Ensure the LRI have landed before we invalidate & continue */ *cs++ = MI_LOAD_REGISTER_IMM(2 * GEN8_3LVL_PDPES) | MI_LRI_FORCE_POSTED; for (i = GEN8_3LVL_PDPES; i--; ) { const dma_addr_t pd_daddr = i915_page_dir_dma_addr(ppgtt, i); *cs++ = i915_mmio_reg_offset(GEN8_RING_PDP_UDW(engine, i)); *cs++ = upper_32_bits(pd_daddr); *cs++ = i915_mmio_reg_offset(GEN8_RING_PDP_LDW(engine, i)); *cs++ = lower_32_bits(pd_daddr); } *cs++ = MI_NOOP; intel_ring_advance(rq, cs); /* Be doubly sure the LRI have landed before proceeding */ err = engine->emit_flush(rq, EMIT_FLUSH); if (err) return err; /* Re-invalidate the TLB for luck */ return engine->emit_flush(rq, EMIT_INVALIDATE); } static int execlists_request_alloc(struct i915_request *request) { int ret; GEM_BUG_ON(!request->hw_context->pin_count); /* * Flush enough space to reduce the likelihood of waiting after * we start building the request - in which case we will just * have to repeat work. */ request->reserved_space += EXECLISTS_REQUEST_SIZE; /* * Note that after this point, we have committed to using * this request as it is being used to both track the * state of engine initialisation and liveness of the * golden renderstate above. Think twice before you try * to cancel/unwind this request now. */ /* Unconditionally invalidate GPU caches and TLBs. */ if (i915_vm_is_48bit(&request->gem_context->ppgtt->vm)) ret = request->engine->emit_flush(request, EMIT_INVALIDATE); else ret = emit_pdps(request); if (ret) return ret; request->reserved_space -= EXECLISTS_REQUEST_SIZE; return 0; } /* * In this WA we need to set GEN8_L3SQCREG4[21:21] and reset it after * PIPE_CONTROL instruction. This is required for the flush to happen correctly * but there is a slight complication as this is applied in WA batch where the * values are only initialized once so we cannot take register value at the * beginning and reuse it further; hence we save its value to memory, upload a * constant value with bit21 set and then we restore it back with the saved value. * To simplify the WA, a constant value is formed by using the default value * of this register. This shouldn't be a problem because we are only modifying * it for a short period and this batch in non-premptible. We can ofcourse * use additional instructions that read the actual value of the register * at that time and set our bit of interest but it makes the WA complicated. * * This WA is also required for Gen9 so extracting as a function avoids * code duplication. */ static u32 * gen8_emit_flush_coherentl3_wa(struct intel_engine_cs *engine, u32 *batch) { /* NB no one else is allowed to scribble over scratch + 256! */ *batch++ = MI_STORE_REGISTER_MEM_GEN8 | MI_SRM_LRM_GLOBAL_GTT; *batch++ = i915_mmio_reg_offset(GEN8_L3SQCREG4); *batch++ = i915_scratch_offset(engine->i915) + 256; *batch++ = 0; *batch++ = MI_LOAD_REGISTER_IMM(1); *batch++ = i915_mmio_reg_offset(GEN8_L3SQCREG4); *batch++ = 0x40400000 | GEN8_LQSC_FLUSH_COHERENT_LINES; batch = gen8_emit_pipe_control(batch, PIPE_CONTROL_CS_STALL | PIPE_CONTROL_DC_FLUSH_ENABLE, 0); *batch++ = MI_LOAD_REGISTER_MEM_GEN8 | MI_SRM_LRM_GLOBAL_GTT; *batch++ = i915_mmio_reg_offset(GEN8_L3SQCREG4); *batch++ = i915_scratch_offset(engine->i915) + 256; *batch++ = 0; return batch; } /* * Typically we only have one indirect_ctx and per_ctx batch buffer which are * initialized at the beginning and shared across all contexts but this field * helps us to have multiple batches at different offsets and select them based * on a criteria. At the moment this batch always start at the beginning of the page * and at this point we don't have multiple wa_ctx batch buffers. * * The number of WA applied are not known at the beginning; we use this field * to return the no of DWORDS written. * * It is to be noted that this batch does not contain MI_BATCH_BUFFER_END * so it adds NOOPs as padding to make it cacheline aligned. * MI_BATCH_BUFFER_END will be added to perctx batch and both of them together * makes a complete batch buffer. */ static u32 *gen8_init_indirectctx_bb(struct intel_engine_cs *engine, u32 *batch) { /* WaDisableCtxRestoreArbitration:bdw,chv */ *batch++ = MI_ARB_ON_OFF | MI_ARB_DISABLE; /* WaFlushCoherentL3CacheLinesAtContextSwitch:bdw */ if (IS_BROADWELL(engine->i915)) batch = gen8_emit_flush_coherentl3_wa(engine, batch); /* WaClearSlmSpaceAtContextSwitch:bdw,chv */ /* Actual scratch location is at 128 bytes offset */ batch = gen8_emit_pipe_control(batch, PIPE_CONTROL_FLUSH_L3 | PIPE_CONTROL_GLOBAL_GTT_IVB | PIPE_CONTROL_CS_STALL | PIPE_CONTROL_QW_WRITE, i915_scratch_offset(engine->i915) + 2 * CACHELINE_BYTES); *batch++ = MI_ARB_ON_OFF | MI_ARB_ENABLE; /* Pad to end of cacheline */ while ((unsigned long)batch % CACHELINE_BYTES) *batch++ = MI_NOOP; /* * MI_BATCH_BUFFER_END is not required in Indirect ctx BB because * execution depends on the length specified in terms of cache lines * in the register CTX_RCS_INDIRECT_CTX */ return batch; } struct lri { i915_reg_t reg; u32 value; }; static u32 *emit_lri(u32 *batch, const struct lri *lri, unsigned int count) { GEM_BUG_ON(!count || count > 63); *batch++ = MI_LOAD_REGISTER_IMM(count); do { *batch++ = i915_mmio_reg_offset(lri->reg); *batch++ = lri->value; } while (lri++, --count); *batch++ = MI_NOOP; return batch; } static u32 *gen9_init_indirectctx_bb(struct intel_engine_cs *engine, u32 *batch) { static const struct lri lri[] = { /* WaDisableGatherAtSetShaderCommonSlice:skl,bxt,kbl,glk */ { COMMON_SLICE_CHICKEN2, __MASKED_FIELD(GEN9_DISABLE_GATHER_AT_SET_SHADER_COMMON_SLICE, 0), }, /* BSpec: 11391 */ { FF_SLICE_CHICKEN, __MASKED_FIELD(FF_SLICE_CHICKEN_CL_PROVOKING_VERTEX_FIX, FF_SLICE_CHICKEN_CL_PROVOKING_VERTEX_FIX), }, /* BSpec: 11299 */ { _3D_CHICKEN3, __MASKED_FIELD(_3D_CHICKEN_SF_PROVOKING_VERTEX_FIX, _3D_CHICKEN_SF_PROVOKING_VERTEX_FIX), } }; *batch++ = MI_ARB_ON_OFF | MI_ARB_DISABLE; /* WaFlushCoherentL3CacheLinesAtContextSwitch:skl,bxt,glk */ batch = gen8_emit_flush_coherentl3_wa(engine, batch); batch = emit_lri(batch, lri, ARRAY_SIZE(lri)); /* WaMediaPoolStateCmdInWABB:bxt,glk */ if (HAS_POOLED_EU(engine->i915)) { /* * EU pool configuration is setup along with golden context * during context initialization. This value depends on * device type (2x6 or 3x6) and needs to be updated based * on which subslice is disabled especially for 2x6 * devices, however it is safe to load default * configuration of 3x6 device instead of masking off * corresponding bits because HW ignores bits of a disabled * subslice and drops down to appropriate config. Please * see render_state_setup() in i915_gem_render_state.c for * possible configurations, to avoid duplication they are * not shown here again. */ *batch++ = GEN9_MEDIA_POOL_STATE; *batch++ = GEN9_MEDIA_POOL_ENABLE; *batch++ = 0x00777000; *batch++ = 0; *batch++ = 0; *batch++ = 0; } *batch++ = MI_ARB_ON_OFF | MI_ARB_ENABLE; /* Pad to end of cacheline */ while ((unsigned long)batch % CACHELINE_BYTES) *batch++ = MI_NOOP; return batch; } static u32 * gen10_init_indirectctx_bb(struct intel_engine_cs *engine, u32 *batch) { int i; /* * WaPipeControlBefore3DStateSamplePattern: cnl * * Ensure the engine is idle prior to programming a * 3DSTATE_SAMPLE_PATTERN during a context restore. */ batch = gen8_emit_pipe_control(batch, PIPE_CONTROL_CS_STALL, 0); /* * WaPipeControlBefore3DStateSamplePattern says we need 4 dwords for * the PIPE_CONTROL followed by 12 dwords of 0x0, so 16 dwords in * total. However, a PIPE_CONTROL is 6 dwords long, not 4, which is * confusing. Since gen8_emit_pipe_control() already advances the * batch by 6 dwords, we advance the other 10 here, completing a * cacheline. It's not clear if the workaround requires this padding * before other commands, or if it's just the regular padding we would * already have for the workaround bb, so leave it here for now. */ for (i = 0; i < 10; i++) *batch++ = MI_NOOP; /* Pad to end of cacheline */ while ((unsigned long)batch % CACHELINE_BYTES) *batch++ = MI_NOOP; return batch; } #define CTX_WA_BB_OBJ_SIZE (PAGE_SIZE) static int lrc_setup_wa_ctx(struct intel_engine_cs *engine) { struct drm_i915_gem_object *obj; struct i915_vma *vma; int err; obj = i915_gem_object_create(engine->i915, CTX_WA_BB_OBJ_SIZE); if (IS_ERR(obj)) return PTR_ERR(obj); vma = i915_vma_instance(obj, &engine->i915->ggtt.vm, NULL); if (IS_ERR(vma)) { err = PTR_ERR(vma); goto err; } err = i915_vma_pin(vma, 0, 0, PIN_GLOBAL | PIN_HIGH); if (err) goto err; engine->wa_ctx.vma = vma; return 0; err: i915_gem_object_put(obj); return err; } static void lrc_destroy_wa_ctx(struct intel_engine_cs *engine) { i915_vma_unpin_and_release(&engine->wa_ctx.vma, 0); } typedef u32 *(*wa_bb_func_t)(struct intel_engine_cs *engine, u32 *batch); static int intel_init_workaround_bb(struct intel_engine_cs *engine) { struct i915_ctx_workarounds *wa_ctx = &engine->wa_ctx; struct i915_wa_ctx_bb *wa_bb[2] = { &wa_ctx->indirect_ctx, &wa_ctx->per_ctx }; wa_bb_func_t wa_bb_fn[2]; struct page *page; void *batch, *batch_ptr; unsigned int i; int ret; if (GEM_DEBUG_WARN_ON(engine->id != RCS)) return -EINVAL; switch (INTEL_GEN(engine->i915)) { case 11: return 0; case 10: wa_bb_fn[0] = gen10_init_indirectctx_bb; wa_bb_fn[1] = NULL; break; case 9: wa_bb_fn[0] = gen9_init_indirectctx_bb; wa_bb_fn[1] = NULL; break; case 8: wa_bb_fn[0] = gen8_init_indirectctx_bb; wa_bb_fn[1] = NULL; break; default: MISSING_CASE(INTEL_GEN(engine->i915)); return 0; } ret = lrc_setup_wa_ctx(engine); if (ret) { DRM_DEBUG_DRIVER("Failed to setup context WA page: %d\n", ret); return ret; } page = i915_gem_object_get_dirty_page(wa_ctx->vma->obj, 0); batch = batch_ptr = kmap_atomic(page); /* * Emit the two workaround batch buffers, recording the offset from the * start of the workaround batch buffer object for each and their * respective sizes. */ for (i = 0; i < ARRAY_SIZE(wa_bb_fn); i++) { wa_bb[i]->offset = batch_ptr - batch; if (GEM_DEBUG_WARN_ON(!IS_ALIGNED(wa_bb[i]->offset, CACHELINE_BYTES))) { ret = -EINVAL; break; } if (wa_bb_fn[i]) batch_ptr = wa_bb_fn[i](engine, batch_ptr); wa_bb[i]->size = batch_ptr - (batch + wa_bb[i]->offset); } BUG_ON(batch_ptr - batch > CTX_WA_BB_OBJ_SIZE); kunmap_atomic(batch); if (ret) lrc_destroy_wa_ctx(engine); return ret; } static void enable_execlists(struct intel_engine_cs *engine) { struct drm_i915_private *dev_priv = engine->i915; intel_engine_set_hwsp_writemask(engine, ~0u); /* HWSTAM */ /* * Make sure we're not enabling the new 12-deep CSB * FIFO as that requires a slightly updated handling * in the ctx switch irq. Since we're currently only * using only 2 elements of the enhanced execlists the * deeper FIFO it's not needed and it's not worth adding * more statements to the irq handler to support it. */ if (INTEL_GEN(dev_priv) >= 11) I915_WRITE(RING_MODE_GEN7(engine), _MASKED_BIT_DISABLE(GEN11_GFX_DISABLE_LEGACY_MODE)); else I915_WRITE(RING_MODE_GEN7(engine), _MASKED_BIT_ENABLE(GFX_RUN_LIST_ENABLE)); I915_WRITE(RING_MI_MODE(engine->mmio_base), _MASKED_BIT_DISABLE(STOP_RING)); I915_WRITE(RING_HWS_PGA(engine->mmio_base), i915_ggtt_offset(engine->status_page.vma)); POSTING_READ(RING_HWS_PGA(engine->mmio_base)); } static bool unexpected_starting_state(struct intel_engine_cs *engine) { struct drm_i915_private *dev_priv = engine->i915; bool unexpected = false; if (I915_READ(RING_MI_MODE(engine->mmio_base)) & STOP_RING) { DRM_DEBUG_DRIVER("STOP_RING still set in RING_MI_MODE\n"); unexpected = true; } return unexpected; } static int gen8_init_common_ring(struct intel_engine_cs *engine) { intel_engine_apply_workarounds(engine); intel_engine_apply_whitelist(engine); intel_mocs_init_engine(engine); intel_engine_reset_breadcrumbs(engine); if (GEM_SHOW_DEBUG() && unexpected_starting_state(engine)) { struct drm_printer p = drm_debug_printer(__func__); intel_engine_dump(engine, &p, NULL); } enable_execlists(engine); return 0; } static void execlists_reset_prepare(struct intel_engine_cs *engine) { struct intel_engine_execlists * const execlists = &engine->execlists; unsigned long flags; GEM_TRACE("%s: depth<-%d\n", engine->name, atomic_read(&execlists->tasklet.count)); /* * Prevent request submission to the hardware until we have * completed the reset in i915_gem_reset_finish(). If a request * is completed by one engine, it may then queue a request * to a second via its execlists->tasklet *just* as we are * calling engine->init_hw() and also writing the ELSP. * Turning off the execlists->tasklet until the reset is over * prevents the race. */ __tasklet_disable_sync_once(&execlists->tasklet); GEM_BUG_ON(!reset_in_progress(execlists)); /* And flush any current direct submission. */ spin_lock_irqsave(&engine->timeline.lock, flags); process_csb(engine); /* drain preemption events */ spin_unlock_irqrestore(&engine->timeline.lock, flags); } static void execlists_reset(struct intel_engine_cs *engine, bool stalled) { struct intel_engine_execlists * const execlists = &engine->execlists; struct i915_request *rq; unsigned long flags; u32 *regs; spin_lock_irqsave(&engine->timeline.lock, flags); /* * Catch up with any missed context-switch interrupts. * * Ideally we would just read the remaining CSB entries now that we * know the gpu is idle. However, the CSB registers are sometimes^W * often trashed across a GPU reset! Instead we have to rely on * guessing the missed context-switch events by looking at what * requests were completed. */ execlists_cancel_port_requests(execlists); /* Push back any incomplete requests for replay after the reset. */ rq = __unwind_incomplete_requests(engine); /* Following the reset, we need to reload the CSB read/write pointers */ reset_csb_pointers(&engine->execlists); GEM_TRACE("%s seqno=%d, current=%d, stalled? %s\n", engine->name, rq ? rq->global_seqno : 0, intel_engine_get_seqno(engine), yesno(stalled)); if (!rq) goto out_unlock; /* * If the request was innocent, we leave the request in the ELSP * and will try to replay it on restarting. The context image may * have been corrupted by the reset, in which case we may have * to service a new GPU hang, but more likely we can continue on * without impact. * * If the request was guilty, we presume the context is corrupt * and have to at least restore the RING register in the context * image back to the expected values to skip over the guilty request. */ i915_reset_request(rq, stalled); if (!stalled) goto out_unlock; /* * We want a simple context + ring to execute the breadcrumb update. * We cannot rely on the context being intact across the GPU hang, * so clear it and rebuild just what we need for the breadcrumb. * All pending requests for this context will be zapped, and any * future request will be after userspace has had the opportunity * to recreate its own state. */ regs = rq->hw_context->lrc_reg_state; if (engine->pinned_default_state) { memcpy(regs, /* skip restoring the vanilla PPHWSP */ engine->pinned_default_state + LRC_STATE_PN * PAGE_SIZE, engine->context_size - PAGE_SIZE); } /* Move the RING_HEAD onto the breadcrumb, past the hanging batch */ rq->ring->head = intel_ring_wrap(rq->ring, rq->postfix); intel_ring_update_space(rq->ring); execlists_init_reg_state(regs, rq->gem_context, engine, rq->ring); __execlists_update_reg_state(engine, rq->hw_context); out_unlock: spin_unlock_irqrestore(&engine->timeline.lock, flags); } static void execlists_reset_finish(struct intel_engine_cs *engine) { struct intel_engine_execlists * const execlists = &engine->execlists; /* * After a GPU reset, we may have requests to replay. Do so now while * we still have the forcewake to be sure that the GPU is not allowed * to sleep before we restart and reload a context. * */ GEM_BUG_ON(!reset_in_progress(execlists)); if (!RB_EMPTY_ROOT(&execlists->queue.rb_root)) execlists->tasklet.func(execlists->tasklet.data); tasklet_enable(&execlists->tasklet); GEM_TRACE("%s: depth->%d\n", engine->name, atomic_read(&execlists->tasklet.count)); } static int gen8_emit_bb_start(struct i915_request *rq, u64 offset, u32 len, const unsigned int flags) { u32 *cs; cs = intel_ring_begin(rq, 6); if (IS_ERR(cs)) return PTR_ERR(cs); /* * WaDisableCtxRestoreArbitration:bdw,chv * * We don't need to perform MI_ARB_ENABLE as often as we do (in * particular all the gen that do not need the w/a at all!), if we * took care to make sure that on every switch into this context * (both ordinary and for preemption) that arbitrartion was enabled * we would be fine. However, there doesn't seem to be a downside to * being paranoid and making sure it is set before each batch and * every context-switch. * * Note that if we fail to enable arbitration before the request * is complete, then we do not see the context-switch interrupt and * the engine hangs (with RING_HEAD == RING_TAIL). * * That satisfies both the GPGPU w/a and our heavy-handed paranoia. */ *cs++ = MI_ARB_ON_OFF | MI_ARB_ENABLE; /* FIXME(BDW): Address space and security selectors. */ *cs++ = MI_BATCH_BUFFER_START_GEN8 | (flags & I915_DISPATCH_SECURE ? 0 : BIT(8)); *cs++ = lower_32_bits(offset); *cs++ = upper_32_bits(offset); *cs++ = MI_ARB_ON_OFF | MI_ARB_DISABLE; *cs++ = MI_NOOP; intel_ring_advance(rq, cs); return 0; } static void gen8_logical_ring_enable_irq(struct intel_engine_cs *engine) { struct drm_i915_private *dev_priv = engine->i915; I915_WRITE_IMR(engine, ~(engine->irq_enable_mask | engine->irq_keep_mask)); POSTING_READ_FW(RING_IMR(engine->mmio_base)); } static void gen8_logical_ring_disable_irq(struct intel_engine_cs *engine) { struct drm_i915_private *dev_priv = engine->i915; I915_WRITE_IMR(engine, ~engine->irq_keep_mask); } static int gen8_emit_flush(struct i915_request *request, u32 mode) { u32 cmd, *cs; cs = intel_ring_begin(request, 4); if (IS_ERR(cs)) return PTR_ERR(cs); cmd = MI_FLUSH_DW + 1; /* We always require a command barrier so that subsequent * commands, such as breadcrumb interrupts, are strictly ordered * wrt the contents of the write cache being flushed to memory * (and thus being coherent from the CPU). */ cmd |= MI_FLUSH_DW_STORE_INDEX | MI_FLUSH_DW_OP_STOREDW; if (mode & EMIT_INVALIDATE) { cmd |= MI_INVALIDATE_TLB; if (request->engine->class == VIDEO_DECODE_CLASS) cmd |= MI_INVALIDATE_BSD; } *cs++ = cmd; *cs++ = I915_GEM_HWS_SCRATCH_ADDR | MI_FLUSH_DW_USE_GTT; *cs++ = 0; /* upper addr */ *cs++ = 0; /* value */ intel_ring_advance(request, cs); return 0; } static int gen8_emit_flush_render(struct i915_request *request, u32 mode) { struct intel_engine_cs *engine = request->engine; u32 scratch_addr = i915_scratch_offset(engine->i915) + 2 * CACHELINE_BYTES; bool vf_flush_wa = false, dc_flush_wa = false; u32 *cs, flags = 0; int len; flags |= PIPE_CONTROL_CS_STALL; if (mode & EMIT_FLUSH) { flags |= PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH; flags |= PIPE_CONTROL_DEPTH_CACHE_FLUSH; flags |= PIPE_CONTROL_DC_FLUSH_ENABLE; flags |= PIPE_CONTROL_FLUSH_ENABLE; } if (mode & EMIT_INVALIDATE) { flags |= PIPE_CONTROL_TLB_INVALIDATE; flags |= PIPE_CONTROL_INSTRUCTION_CACHE_INVALIDATE; flags |= PIPE_CONTROL_TEXTURE_CACHE_INVALIDATE; flags |= PIPE_CONTROL_VF_CACHE_INVALIDATE; flags |= PIPE_CONTROL_CONST_CACHE_INVALIDATE; flags |= PIPE_CONTROL_STATE_CACHE_INVALIDATE; flags |= PIPE_CONTROL_QW_WRITE; flags |= PIPE_CONTROL_GLOBAL_GTT_IVB; /* * On GEN9: before VF_CACHE_INVALIDATE we need to emit a NULL * pipe control. */ if (IS_GEN(request->i915, 9)) vf_flush_wa = true; /* WaForGAMHang:kbl */ if (IS_KBL_REVID(request->i915, 0, KBL_REVID_B0)) dc_flush_wa = true; } len = 6; if (vf_flush_wa) len += 6; if (dc_flush_wa) len += 12; cs = intel_ring_begin(request, len); if (IS_ERR(cs)) return PTR_ERR(cs); if (vf_flush_wa) cs = gen8_emit_pipe_control(cs, 0, 0); if (dc_flush_wa) cs = gen8_emit_pipe_control(cs, PIPE_CONTROL_DC_FLUSH_ENABLE, 0); cs = gen8_emit_pipe_control(cs, flags, scratch_addr); if (dc_flush_wa) cs = gen8_emit_pipe_control(cs, PIPE_CONTROL_CS_STALL, 0); intel_ring_advance(request, cs); return 0; } /* * Reserve space for 2 NOOPs at the end of each request to be * used as a workaround for not being allowed to do lite * restore with HEAD==TAIL (WaIdleLiteRestore). */ static u32 *gen8_emit_wa_tail(struct i915_request *request, u32 *cs) { /* Ensure there's always at least one preemption point per-request. */ *cs++ = MI_ARB_CHECK; *cs++ = MI_NOOP; request->wa_tail = intel_ring_offset(request, cs); return cs; } static u32 *gen8_emit_fini_breadcrumb(struct i915_request *request, u32 *cs) { /* w/a: bit 5 needs to be zero for MI_FLUSH_DW address. */ BUILD_BUG_ON(I915_GEM_HWS_INDEX_ADDR & (1 << 5)); cs = gen8_emit_ggtt_write(cs, request->fence.seqno, request->timeline->hwsp_offset); cs = gen8_emit_ggtt_write(cs, request->global_seqno, intel_hws_seqno_address(request->engine)); *cs++ = MI_USER_INTERRUPT; *cs++ = MI_ARB_ON_OFF | MI_ARB_ENABLE; request->tail = intel_ring_offset(request, cs); assert_ring_tail_valid(request->ring, request->tail); return gen8_emit_wa_tail(request, cs); } static u32 *gen8_emit_fini_breadcrumb_rcs(struct i915_request *request, u32 *cs) { cs = gen8_emit_ggtt_write_rcs(cs, request->fence.seqno, request->timeline->hwsp_offset, PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH | PIPE_CONTROL_DEPTH_CACHE_FLUSH | PIPE_CONTROL_DC_FLUSH_ENABLE | PIPE_CONTROL_FLUSH_ENABLE | PIPE_CONTROL_CS_STALL); cs = gen8_emit_ggtt_write_rcs(cs, request->global_seqno, intel_hws_seqno_address(request->engine), PIPE_CONTROL_CS_STALL); *cs++ = MI_USER_INTERRUPT; *cs++ = MI_ARB_ON_OFF | MI_ARB_ENABLE; request->tail = intel_ring_offset(request, cs); assert_ring_tail_valid(request->ring, request->tail); return gen8_emit_wa_tail(request, cs); } static int gen8_init_rcs_context(struct i915_request *rq) { int ret; ret = intel_engine_emit_ctx_wa(rq); if (ret) return ret; ret = intel_rcs_context_init_mocs(rq); /* * Failing to program the MOCS is non-fatal.The system will not * run at peak performance. So generate an error and carry on. */ if (ret) DRM_ERROR("MOCS failed to program: expect performance issues.\n"); return i915_gem_render_state_emit(rq); } /** * intel_logical_ring_cleanup() - deallocate the Engine Command Streamer * @engine: Engine Command Streamer. */ void intel_logical_ring_cleanup(struct intel_engine_cs *engine) { struct drm_i915_private *dev_priv; /* * Tasklet cannot be active at this point due intel_mark_active/idle * so this is just for documentation. */ if (WARN_ON(test_bit(TASKLET_STATE_SCHED, &engine->execlists.tasklet.state))) tasklet_kill(&engine->execlists.tasklet); dev_priv = engine->i915; if (engine->buffer) { WARN_ON((I915_READ_MODE(engine) & MODE_IDLE) == 0); } if (engine->cleanup) engine->cleanup(engine); intel_engine_cleanup_common(engine); lrc_destroy_wa_ctx(engine); engine->i915 = NULL; dev_priv->engine[engine->id] = NULL; kfree(engine); } void intel_execlists_set_default_submission(struct intel_engine_cs *engine) { engine->submit_request = execlists_submit_request; engine->cancel_requests = execlists_cancel_requests; engine->schedule = i915_schedule; engine->execlists.tasklet.func = execlists_submission_tasklet; engine->reset.prepare = execlists_reset_prepare; engine->park = NULL; engine->unpark = NULL; engine->flags |= I915_ENGINE_SUPPORTS_STATS; if (engine->i915->preempt_context) engine->flags |= I915_ENGINE_HAS_PREEMPTION; engine->i915->caps.scheduler = I915_SCHEDULER_CAP_ENABLED | I915_SCHEDULER_CAP_PRIORITY; if (intel_engine_has_preemption(engine)) engine->i915->caps.scheduler |= I915_SCHEDULER_CAP_PREEMPTION; } static void logical_ring_default_vfuncs(struct intel_engine_cs *engine) { /* Default vfuncs which can be overriden by each engine. */ engine->init_hw = gen8_init_common_ring; engine->reset.prepare = execlists_reset_prepare; engine->reset.reset = execlists_reset; engine->reset.finish = execlists_reset_finish; engine->context_pin = execlists_context_pin; engine->request_alloc = execlists_request_alloc; engine->emit_flush = gen8_emit_flush; engine->emit_init_breadcrumb = gen8_emit_init_breadcrumb; engine->emit_fini_breadcrumb = gen8_emit_fini_breadcrumb; engine->set_default_submission = intel_execlists_set_default_submission; if (INTEL_GEN(engine->i915) < 11) { engine->irq_enable = gen8_logical_ring_enable_irq; engine->irq_disable = gen8_logical_ring_disable_irq; } else { /* * TODO: On Gen11 interrupt masks need to be clear * to allow C6 entry. Keep interrupts enabled at * and take the hit of generating extra interrupts * until a more refined solution exists. */ } engine->emit_bb_start = gen8_emit_bb_start; } static inline void logical_ring_default_irqs(struct intel_engine_cs *engine) { unsigned int shift = 0; if (INTEL_GEN(engine->i915) < 11) { const u8 irq_shifts[] = { [RCS] = GEN8_RCS_IRQ_SHIFT, [BCS] = GEN8_BCS_IRQ_SHIFT, [VCS] = GEN8_VCS1_IRQ_SHIFT, [VCS2] = GEN8_VCS2_IRQ_SHIFT, [VECS] = GEN8_VECS_IRQ_SHIFT, }; shift = irq_shifts[engine->id]; } engine->irq_enable_mask = GT_RENDER_USER_INTERRUPT << shift; engine->irq_keep_mask = GT_CONTEXT_SWITCH_INTERRUPT << shift; } static int logical_ring_setup(struct intel_engine_cs *engine) { int err; err = intel_engine_setup_common(engine); if (err) return err; /* Intentionally left blank. */ engine->buffer = NULL; tasklet_init(&engine->execlists.tasklet, execlists_submission_tasklet, (unsigned long)engine); logical_ring_default_vfuncs(engine); logical_ring_default_irqs(engine); return 0; } static int logical_ring_init(struct intel_engine_cs *engine) { struct drm_i915_private *i915 = engine->i915; struct intel_engine_execlists * const execlists = &engine->execlists; int ret; ret = intel_engine_init_common(engine); if (ret) return ret; intel_engine_init_workarounds(engine); if (HAS_LOGICAL_RING_ELSQ(i915)) { execlists->submit_reg = i915->regs + i915_mmio_reg_offset(RING_EXECLIST_SQ_CONTENTS(engine)); execlists->ctrl_reg = i915->regs + i915_mmio_reg_offset(RING_EXECLIST_CONTROL(engine)); } else { execlists->submit_reg = i915->regs + i915_mmio_reg_offset(RING_ELSP(engine)); } execlists->preempt_complete_status = ~0u; if (i915->preempt_context) { struct intel_context *ce = to_intel_context(i915->preempt_context, engine); execlists->preempt_complete_status = upper_32_bits(ce->lrc_desc); } execlists->csb_status = &engine->status_page.addr[I915_HWS_CSB_BUF0_INDEX]; execlists->csb_write = &engine->status_page.addr[intel_hws_csb_write_index(i915)]; reset_csb_pointers(execlists); return 0; } int logical_render_ring_init(struct intel_engine_cs *engine) { int ret; ret = logical_ring_setup(engine); if (ret) return ret; /* Override some for render ring. */ engine->init_context = gen8_init_rcs_context; engine->emit_flush = gen8_emit_flush_render; engine->emit_fini_breadcrumb = gen8_emit_fini_breadcrumb_rcs; ret = logical_ring_init(engine); if (ret) return ret; ret = intel_init_workaround_bb(engine); if (ret) { /* * We continue even if we fail to initialize WA batch * because we only expect rare glitches but nothing * critical to prevent us from using GPU */ DRM_ERROR("WA batch buffer initialization failed: %d\n", ret); } intel_engine_init_whitelist(engine); return 0; } int logical_xcs_ring_init(struct intel_engine_cs *engine) { int err; err = logical_ring_setup(engine); if (err) return err; return logical_ring_init(engine); } static u32 make_rpcs(struct drm_i915_private *dev_priv) { bool subslice_pg = RUNTIME_INFO(dev_priv)->sseu.has_subslice_pg; u8 slices = hweight8(RUNTIME_INFO(dev_priv)->sseu.slice_mask); u8 subslices = hweight8(RUNTIME_INFO(dev_priv)->sseu.subslice_mask[0]); u32 rpcs = 0; /* * No explicit RPCS request is needed to ensure full * slice/subslice/EU enablement prior to Gen9. */ if (INTEL_GEN(dev_priv) < 9) return 0; /* * Since the SScount bitfield in GEN8_R_PWR_CLK_STATE is only three bits * wide and Icelake has up to eight subslices, specfial programming is * needed in order to correctly enable all subslices. * * According to documentation software must consider the configuration * as 2x4x8 and hardware will translate this to 1x8x8. * * Furthemore, even though SScount is three bits, maximum documented * value for it is four. From this some rules/restrictions follow: * * 1. * If enabled subslice count is greater than four, two whole slices must * be enabled instead. * * 2. * When more than one slice is enabled, hardware ignores the subslice * count altogether. * * From these restrictions it follows that it is not possible to enable * a count of subslices between the SScount maximum of four restriction, * and the maximum available number on a particular SKU. Either all * subslices are enabled, or a count between one and four on the first * slice. */ if (IS_GEN(dev_priv, 11) && slices == 1 && subslices >= 4) { GEM_BUG_ON(subslices & 1); subslice_pg = false; slices *= 2; } /* * Starting in Gen9, render power gating can leave * slice/subslice/EU in a partially enabled state. We * must make an explicit request through RPCS for full * enablement. */ if (RUNTIME_INFO(dev_priv)->sseu.has_slice_pg) { u32 mask, val = slices; if (INTEL_GEN(dev_priv) >= 11) { mask = GEN11_RPCS_S_CNT_MASK; val <<= GEN11_RPCS_S_CNT_SHIFT; } else { mask = GEN8_RPCS_S_CNT_MASK; val <<= GEN8_RPCS_S_CNT_SHIFT; } GEM_BUG_ON(val & ~mask); val &= mask; rpcs |= GEN8_RPCS_ENABLE | GEN8_RPCS_S_CNT_ENABLE | val; } if (subslice_pg) { u32 val = subslices; val <<= GEN8_RPCS_SS_CNT_SHIFT; GEM_BUG_ON(val & ~GEN8_RPCS_SS_CNT_MASK); val &= GEN8_RPCS_SS_CNT_MASK; rpcs |= GEN8_RPCS_ENABLE | GEN8_RPCS_SS_CNT_ENABLE | val; } if (RUNTIME_INFO(dev_priv)->sseu.has_eu_pg) { u32 val; val = RUNTIME_INFO(dev_priv)->sseu.eu_per_subslice << GEN8_RPCS_EU_MIN_SHIFT; GEM_BUG_ON(val & ~GEN8_RPCS_EU_MIN_MASK); val &= GEN8_RPCS_EU_MIN_MASK; rpcs |= val; val = RUNTIME_INFO(dev_priv)->sseu.eu_per_subslice << GEN8_RPCS_EU_MAX_SHIFT; GEM_BUG_ON(val & ~GEN8_RPCS_EU_MAX_MASK); val &= GEN8_RPCS_EU_MAX_MASK; rpcs |= val; rpcs |= GEN8_RPCS_ENABLE; } return rpcs; } static u32 intel_lr_indirect_ctx_offset(struct intel_engine_cs *engine) { u32 indirect_ctx_offset; switch (INTEL_GEN(engine->i915)) { default: MISSING_CASE(INTEL_GEN(engine->i915)); /* fall through */ case 11: indirect_ctx_offset = GEN11_CTX_RCS_INDIRECT_CTX_OFFSET_DEFAULT; break; case 10: indirect_ctx_offset = GEN10_CTX_RCS_INDIRECT_CTX_OFFSET_DEFAULT; break; case 9: indirect_ctx_offset = GEN9_CTX_RCS_INDIRECT_CTX_OFFSET_DEFAULT; break; case 8: indirect_ctx_offset = GEN8_CTX_RCS_INDIRECT_CTX_OFFSET_DEFAULT; break; } return indirect_ctx_offset; } static void execlists_init_reg_state(u32 *regs, struct i915_gem_context *ctx, struct intel_engine_cs *engine, struct intel_ring *ring) { struct drm_i915_private *dev_priv = engine->i915; u32 base = engine->mmio_base; bool rcs = engine->class == RENDER_CLASS; /* A context is actually a big batch buffer with several * MI_LOAD_REGISTER_IMM commands followed by (reg, value) pairs. The * values we are setting here are only for the first context restore: * on a subsequent save, the GPU will recreate this batchbuffer with new * values (including all the missing MI_LOAD_REGISTER_IMM commands that * we are not initializing here). */ regs[CTX_LRI_HEADER_0] = MI_LOAD_REGISTER_IMM(rcs ? 14 : 11) | MI_LRI_FORCE_POSTED; CTX_REG(regs, CTX_CONTEXT_CONTROL, RING_CONTEXT_CONTROL(engine), _MASKED_BIT_DISABLE(CTX_CTRL_ENGINE_CTX_RESTORE_INHIBIT) | _MASKED_BIT_ENABLE(CTX_CTRL_INHIBIT_SYN_CTX_SWITCH)); if (INTEL_GEN(dev_priv) < 11) { regs[CTX_CONTEXT_CONTROL + 1] |= _MASKED_BIT_DISABLE(CTX_CTRL_ENGINE_CTX_SAVE_INHIBIT | CTX_CTRL_RS_CTX_ENABLE); } CTX_REG(regs, CTX_RING_HEAD, RING_HEAD(base), 0); CTX_REG(regs, CTX_RING_TAIL, RING_TAIL(base), 0); CTX_REG(regs, CTX_RING_BUFFER_START, RING_START(base), 0); CTX_REG(regs, CTX_RING_BUFFER_CONTROL, RING_CTL(base), RING_CTL_SIZE(ring->size) | RING_VALID); CTX_REG(regs, CTX_BB_HEAD_U, RING_BBADDR_UDW(base), 0); CTX_REG(regs, CTX_BB_HEAD_L, RING_BBADDR(base), 0); CTX_REG(regs, CTX_BB_STATE, RING_BBSTATE(base), RING_BB_PPGTT); CTX_REG(regs, CTX_SECOND_BB_HEAD_U, RING_SBBADDR_UDW(base), 0); CTX_REG(regs, CTX_SECOND_BB_HEAD_L, RING_SBBADDR(base), 0); CTX_REG(regs, CTX_SECOND_BB_STATE, RING_SBBSTATE(base), 0); if (rcs) { struct i915_ctx_workarounds *wa_ctx = &engine->wa_ctx; CTX_REG(regs, CTX_RCS_INDIRECT_CTX, RING_INDIRECT_CTX(base), 0); CTX_REG(regs, CTX_RCS_INDIRECT_CTX_OFFSET, RING_INDIRECT_CTX_OFFSET(base), 0); if (wa_ctx->indirect_ctx.size) { u32 ggtt_offset = i915_ggtt_offset(wa_ctx->vma); regs[CTX_RCS_INDIRECT_CTX + 1] = (ggtt_offset + wa_ctx->indirect_ctx.offset) | (wa_ctx->indirect_ctx.size / CACHELINE_BYTES); regs[CTX_RCS_INDIRECT_CTX_OFFSET + 1] = intel_lr_indirect_ctx_offset(engine) << 6; } CTX_REG(regs, CTX_BB_PER_CTX_PTR, RING_BB_PER_CTX_PTR(base), 0); if (wa_ctx->per_ctx.size) { u32 ggtt_offset = i915_ggtt_offset(wa_ctx->vma); regs[CTX_BB_PER_CTX_PTR + 1] = (ggtt_offset + wa_ctx->per_ctx.offset) | 0x01; } } regs[CTX_LRI_HEADER_1] = MI_LOAD_REGISTER_IMM(9) | MI_LRI_FORCE_POSTED; CTX_REG(regs, CTX_CTX_TIMESTAMP, RING_CTX_TIMESTAMP(base), 0); /* PDP values well be assigned later if needed */ CTX_REG(regs, CTX_PDP3_UDW, GEN8_RING_PDP_UDW(engine, 3), 0); CTX_REG(regs, CTX_PDP3_LDW, GEN8_RING_PDP_LDW(engine, 3), 0); CTX_REG(regs, CTX_PDP2_UDW, GEN8_RING_PDP_UDW(engine, 2), 0); CTX_REG(regs, CTX_PDP2_LDW, GEN8_RING_PDP_LDW(engine, 2), 0); CTX_REG(regs, CTX_PDP1_UDW, GEN8_RING_PDP_UDW(engine, 1), 0); CTX_REG(regs, CTX_PDP1_LDW, GEN8_RING_PDP_LDW(engine, 1), 0); CTX_REG(regs, CTX_PDP0_UDW, GEN8_RING_PDP_UDW(engine, 0), 0); CTX_REG(regs, CTX_PDP0_LDW, GEN8_RING_PDP_LDW(engine, 0), 0); if (i915_vm_is_48bit(&ctx->ppgtt->vm)) { /* 64b PPGTT (48bit canonical) * PDP0_DESCRIPTOR contains the base address to PML4 and * other PDP Descriptors are ignored. */ ASSIGN_CTX_PML4(ctx->ppgtt, regs); } else { ASSIGN_CTX_PDP(ctx->ppgtt, regs, 3); ASSIGN_CTX_PDP(ctx->ppgtt, regs, 2); ASSIGN_CTX_PDP(ctx->ppgtt, regs, 1); ASSIGN_CTX_PDP(ctx->ppgtt, regs, 0); } if (rcs) { regs[CTX_LRI_HEADER_2] = MI_LOAD_REGISTER_IMM(1); CTX_REG(regs, CTX_R_PWR_CLK_STATE, GEN8_R_PWR_CLK_STATE, 0); i915_oa_init_reg_state(engine, ctx, regs); } regs[CTX_END] = MI_BATCH_BUFFER_END; if (INTEL_GEN(dev_priv) >= 10) regs[CTX_END] |= BIT(0); } static int populate_lr_context(struct i915_gem_context *ctx, struct drm_i915_gem_object *ctx_obj, struct intel_engine_cs *engine, struct intel_ring *ring) { void *vaddr; u32 *regs; int ret; ret = i915_gem_object_set_to_cpu_domain(ctx_obj, true); if (ret) { DRM_DEBUG_DRIVER("Could not set to CPU domain\n"); return ret; } vaddr = i915_gem_object_pin_map(ctx_obj, I915_MAP_WB); if (IS_ERR(vaddr)) { ret = PTR_ERR(vaddr); DRM_DEBUG_DRIVER("Could not map object pages! (%d)\n", ret); return ret; } ctx_obj->mm.dirty = true; if (engine->default_state) { /* * We only want to copy over the template context state; * skipping over the headers reserved for GuC communication, * leaving those as zero. */ const unsigned long start = LRC_HEADER_PAGES * PAGE_SIZE; void *defaults; defaults = i915_gem_object_pin_map(engine->default_state, I915_MAP_WB); if (IS_ERR(defaults)) { ret = PTR_ERR(defaults); goto err_unpin_ctx; } memcpy(vaddr + start, defaults + start, engine->context_size); i915_gem_object_unpin_map(engine->default_state); } /* The second page of the context object contains some fields which must * be set up prior to the first execution. */ regs = vaddr + LRC_STATE_PN * PAGE_SIZE; execlists_init_reg_state(regs, ctx, engine, ring); if (!engine->default_state) regs[CTX_CONTEXT_CONTROL + 1] |= _MASKED_BIT_ENABLE(CTX_CTRL_ENGINE_CTX_RESTORE_INHIBIT); if (ctx == ctx->i915->preempt_context && INTEL_GEN(engine->i915) < 11) regs[CTX_CONTEXT_CONTROL + 1] |= _MASKED_BIT_ENABLE(CTX_CTRL_ENGINE_CTX_RESTORE_INHIBIT | CTX_CTRL_ENGINE_CTX_SAVE_INHIBIT); err_unpin_ctx: i915_gem_object_unpin_map(ctx_obj); return ret; } static int execlists_context_deferred_alloc(struct i915_gem_context *ctx, struct intel_engine_cs *engine, struct intel_context *ce) { struct drm_i915_gem_object *ctx_obj; struct i915_vma *vma; u32 context_size; struct intel_ring *ring; struct i915_timeline *timeline; int ret; if (ce->state) return 0; context_size = round_up(engine->context_size, I915_GTT_PAGE_SIZE); /* * Before the actual start of the context image, we insert a few pages * for our own use and for sharing with the GuC. */ context_size += LRC_HEADER_PAGES * PAGE_SIZE; ctx_obj = i915_gem_object_create(ctx->i915, context_size); if (IS_ERR(ctx_obj)) return PTR_ERR(ctx_obj); vma = i915_vma_instance(ctx_obj, &ctx->i915->ggtt.vm, NULL); if (IS_ERR(vma)) { ret = PTR_ERR(vma); goto error_deref_obj; } timeline = i915_timeline_create(ctx->i915, ctx->name, NULL); if (IS_ERR(timeline)) { ret = PTR_ERR(timeline); goto error_deref_obj; } ring = intel_engine_create_ring(engine, timeline, ctx->ring_size); i915_timeline_put(timeline); if (IS_ERR(ring)) { ret = PTR_ERR(ring); goto error_deref_obj; } ret = populate_lr_context(ctx, ctx_obj, engine, ring); if (ret) { DRM_DEBUG_DRIVER("Failed to populate LRC: %d\n", ret); goto error_ring_free; } ce->ring = ring; ce->state = vma; return 0; error_ring_free: intel_ring_free(ring); error_deref_obj: i915_gem_object_put(ctx_obj); return ret; } void intel_lr_context_resume(struct drm_i915_private *i915) { struct intel_engine_cs *engine; struct i915_gem_context *ctx; enum intel_engine_id id; /* * Because we emit WA_TAIL_DWORDS there may be a disparity * between our bookkeeping in ce->ring->head and ce->ring->tail and * that stored in context. As we only write new commands from * ce->ring->tail onwards, everything before that is junk. If the GPU * starts reading from its RING_HEAD from the context, it may try to * execute that junk and die. * * So to avoid that we reset the context images upon resume. For * simplicity, we just zero everything out. */ list_for_each_entry(ctx, &i915->contexts.list, link) { for_each_engine(engine, i915, id) { struct intel_context *ce = to_intel_context(ctx, engine); if (!ce->state) continue; intel_ring_reset(ce->ring, 0); if (ce->pin_count) /* otherwise done in context_pin */ __execlists_update_reg_state(engine, ce); } } } void intel_execlists_show_requests(struct intel_engine_cs *engine, struct drm_printer *m, void (*show_request)(struct drm_printer *m, struct i915_request *rq, const char *prefix), unsigned int max) { const struct intel_engine_execlists *execlists = &engine->execlists; struct i915_request *rq, *last; unsigned long flags; unsigned int count; struct rb_node *rb; spin_lock_irqsave(&engine->timeline.lock, flags); last = NULL; count = 0; list_for_each_entry(rq, &engine->timeline.requests, link) { if (count++ < max - 1) show_request(m, rq, "\t\tE "); else last = rq; } if (last) { if (count > max) { drm_printf(m, "\t\t...skipping %d executing requests...\n", count - max); } show_request(m, last, "\t\tE "); } last = NULL; count = 0; if (execlists->queue_priority_hint != INT_MIN) drm_printf(m, "\t\tQueue priority hint: %d\n", execlists->queue_priority_hint); for (rb = rb_first_cached(&execlists->queue); rb; rb = rb_next(rb)) { struct i915_priolist *p = rb_entry(rb, typeof(*p), node); int i; priolist_for_each_request(rq, p, i) { if (count++ < max - 1) show_request(m, rq, "\t\tQ "); else last = rq; } } if (last) { if (count > max) { drm_printf(m, "\t\t...skipping %d queued requests...\n", count - max); } show_request(m, last, "\t\tQ "); } spin_unlock_irqrestore(&engine->timeline.lock, flags); } #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST) #include "selftests/intel_lrc.c" #endif