/* * 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 #include "i915_drv.h" #include "intel_mocs.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_ACTIVE_IDLE | \ GEN8_CTX_STATUS_PREEMPTED | \ GEN8_CTX_STATUS_ELEMENT_SWITCH) #define CTX_LRI_HEADER_0 0x01 #define CTX_CONTEXT_CONTROL 0x02 #define CTX_RING_HEAD 0x04 #define CTX_RING_TAIL 0x06 #define CTX_RING_BUFFER_START 0x08 #define CTX_RING_BUFFER_CONTROL 0x0a #define CTX_BB_HEAD_U 0x0c #define CTX_BB_HEAD_L 0x0e #define CTX_BB_STATE 0x10 #define CTX_SECOND_BB_HEAD_U 0x12 #define CTX_SECOND_BB_HEAD_L 0x14 #define CTX_SECOND_BB_STATE 0x16 #define CTX_BB_PER_CTX_PTR 0x18 #define CTX_RCS_INDIRECT_CTX 0x1a #define CTX_RCS_INDIRECT_CTX_OFFSET 0x1c #define CTX_LRI_HEADER_1 0x21 #define CTX_CTX_TIMESTAMP 0x22 #define CTX_PDP3_UDW 0x24 #define CTX_PDP3_LDW 0x26 #define CTX_PDP2_UDW 0x28 #define CTX_PDP2_LDW 0x2a #define CTX_PDP1_UDW 0x2c #define CTX_PDP1_LDW 0x2e #define CTX_PDP0_UDW 0x30 #define CTX_PDP0_LDW 0x32 #define CTX_LRI_HEADER_2 0x41 #define CTX_R_PWR_CLK_STATE 0x42 #define CTX_GPGPU_CSR_BASE_ADDRESS 0x44 #define CTX_REG(reg_state, pos, reg, val) do { \ (reg_state)[(pos)+0] = i915_mmio_reg_offset(reg); \ (reg_state)[(pos)+1] = (val); \ } while (0) #define ASSIGN_CTX_PDP(ppgtt, reg_state, n) do { \ const u64 _addr = i915_page_dir_dma_addr((ppgtt), (n)); \ reg_state[CTX_PDP ## n ## _UDW+1] = upper_32_bits(_addr); \ reg_state[CTX_PDP ## n ## _LDW+1] = lower_32_bits(_addr); \ } while (0) #define ASSIGN_CTX_PML4(ppgtt, reg_state) do { \ reg_state[CTX_PDP0_UDW + 1] = upper_32_bits(px_dma(&ppgtt->pml4)); \ reg_state[CTX_PDP0_LDW + 1] = lower_32_bits(px_dma(&ppgtt->pml4)); \ } while (0) #define GEN8_CTX_RCS_INDIRECT_CTX_OFFSET_DEFAULT 0x17 #define GEN9_CTX_RCS_INDIRECT_CTX_OFFSET_DEFAULT 0x26 #define GEN10_CTX_RCS_INDIRECT_CTX_OFFSET_DEFAULT 0x19 /* Typical size of the average request (2 pipecontrols and a MI_BB) */ #define EXECLISTS_REQUEST_SIZE 64 /* bytes */ #define WA_TAIL_DWORDS 2 static int execlists_context_deferred_alloc(struct i915_gem_context *ctx, struct intel_engine_cs *engine); static void execlists_init_reg_state(u32 *reg_state, struct i915_gem_context *ctx, struct intel_engine_cs *engine, struct intel_ring *ring); /** * intel_sanitize_enable_execlists() - sanitize i915.enable_execlists * @dev_priv: i915 device private * @enable_execlists: value of i915.enable_execlists module parameter. * * Only certain platforms support Execlists (the prerequisites being * support for Logical Ring Contexts and Aliasing PPGTT or better). * * Return: 1 if Execlists is supported and has to be enabled. */ int intel_sanitize_enable_execlists(struct drm_i915_private *dev_priv, int enable_execlists) { /* On platforms with execlist available, vGPU will only * support execlist mode, no ring buffer mode. */ if (HAS_LOGICAL_RING_CONTEXTS(dev_priv) && intel_vgpu_active(dev_priv)) return 1; if (INTEL_GEN(dev_priv) >= 9) return 1; if (enable_execlists == 0) return 0; if (HAS_LOGICAL_RING_CONTEXTS(dev_priv) && USES_PPGTT(dev_priv) && i915_modparams.use_mmio_flip >= 0) return 1; return 0; } /** * intel_lr_context_descriptor_update() - calculate & cache the descriptor * descriptor for a pinned context * @ctx: Context to work on * @engine: Engine the descriptor will be used with * * 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 * bits 53-54: mbz, reserved for use by hardware * bits 55-63: group ID, currently unused and set to 0 */ static void intel_lr_context_descriptor_update(struct i915_gem_context *ctx, struct intel_engine_cs *engine) { struct intel_context *ce = &ctx->engine[engine->id]; u64 desc; BUILD_BUG_ON(MAX_CONTEXT_HW_ID > (1<desc_template; /* bits 0-11 */ desc |= i915_ggtt_offset(ce->state) + LRC_HEADER_PAGES * PAGE_SIZE; /* bits 12-31 */ desc |= (u64)ctx->hw_id << GEN8_CTX_ID_SHIFT; /* bits 32-52 */ ce->lrc_desc = desc; } static struct i915_priolist * lookup_priolist(struct intel_engine_cs *engine, struct i915_priotree *pt, int prio) { struct intel_engine_execlists * const execlists = &engine->execlists; struct i915_priolist *p; struct rb_node **parent, *rb; bool first = true; if (unlikely(execlists->no_priolist)) prio = I915_PRIORITY_NORMAL; find_priolist: /* most positive priority is scheduled first, equal priorities fifo */ rb = NULL; parent = &execlists->queue.rb_node; while (*parent) { rb = *parent; p = rb_entry(rb, typeof(*p), node); if (prio > p->priority) { parent = &rb->rb_left; } else if (prio < p->priority) { parent = &rb->rb_right; first = false; } else { return p; } } if (prio == I915_PRIORITY_NORMAL) { p = &execlists->default_priolist; } else { p = kmem_cache_alloc(engine->i915->priorities, GFP_ATOMIC); /* Convert an allocation failure to a priority bump */ if (unlikely(!p)) { prio = I915_PRIORITY_NORMAL; /* recurses just once */ /* To maintain ordering with all rendering, after an * allocation failure we have to disable all scheduling. * Requests will then be executed in fifo, and schedule * will ensure that dependencies are emitted in fifo. * There will be still some reordering with existing * requests, so if userspace lied about their * dependencies that reordering may be visible. */ execlists->no_priolist = true; goto find_priolist; } } p->priority = prio; INIT_LIST_HEAD(&p->requests); rb_link_node(&p->node, rb, parent); rb_insert_color(&p->node, &execlists->queue); if (first) execlists->first = &p->node; return ptr_pack_bits(p, first, 1); } static inline void execlists_context_status_change(struct drm_i915_gem_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); } static void execlists_update_context_pdps(struct i915_hw_ppgtt *ppgtt, u32 *reg_state) { ASSIGN_CTX_PDP(ppgtt, reg_state, 3); ASSIGN_CTX_PDP(ppgtt, reg_state, 2); ASSIGN_CTX_PDP(ppgtt, reg_state, 1); ASSIGN_CTX_PDP(ppgtt, reg_state, 0); } static u64 execlists_update_context(struct drm_i915_gem_request *rq) { struct intel_context *ce = &rq->ctx->engine[rq->engine->id]; struct i915_hw_ppgtt *ppgtt = rq->ctx->ppgtt ?: rq->i915->mm.aliasing_ppgtt; u32 *reg_state = ce->lrc_reg_state; reg_state[CTX_RING_TAIL+1] = intel_ring_set_tail(rq->ring, rq->tail); /* True 32b PPGTT with dynamic page allocation: update PDP * registers and point the unallocated PDPs to scratch page. * PML4 is allocated during ppgtt init, so this is not needed * in 48-bit mode. */ if (ppgtt && !i915_vm_is_48bit(&ppgtt->base)) execlists_update_context_pdps(ppgtt, reg_state); return ce->lrc_desc; } static void execlists_submit_ports(struct intel_engine_cs *engine) { struct execlist_port *port = engine->execlists.port; u32 __iomem *elsp = engine->i915->regs + i915_mmio_reg_offset(RING_ELSP(engine)); unsigned int n; for (n = ARRAY_SIZE(engine->execlists.port); n--; ) { struct drm_i915_gem_request *rq; unsigned int count; u64 desc; rq = port_unpack(&port[n], &count); if (rq) { GEM_BUG_ON(count > !n); if (!count++) execlists_context_status_change(rq, INTEL_CONTEXT_SCHEDULE_IN); port_set(&port[n], port_pack(rq, count)); desc = execlists_update_context(rq); GEM_DEBUG_EXEC(port[n].context_id = upper_32_bits(desc)); } else { GEM_BUG_ON(!n); desc = 0; } writel(upper_32_bits(desc), elsp); writel(lower_32_bits(desc), elsp); } } static bool ctx_single_port_submission(const struct i915_gem_context *ctx) { return (IS_ENABLED(CONFIG_DRM_I915_GVT) && i915_gem_context_force_single_submission(ctx)); } static bool can_merge_ctx(const struct i915_gem_context *prev, const struct i915_gem_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 drm_i915_gem_request *rq) { GEM_BUG_ON(rq == port_request(port)); if (port_isset(port)) i915_gem_request_put(port_request(port)); port_set(port, port_pack(i915_gem_request_get(rq), port_count(port))); } static void execlists_dequeue(struct intel_engine_cs *engine) { struct drm_i915_gem_request *last; struct execlist_port *port = engine->execlists.port; struct rb_node *rb; bool submit = false; last = port_request(port); if (last) /* WaIdleLiteRestore:bdw,skl * Apply the wa NOOPs to prevent ring:HEAD == req:TAIL * as we resubmit the request. See gen8_emit_breadcrumb() * for where we prepare the padding after the end of the * request. */ last->tail = last->wa_tail; GEM_BUG_ON(port_isset(&port[1])); /* 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. */ spin_lock_irq(&engine->timeline->lock); rb = engine->execlists.first; GEM_BUG_ON(rb_first(&engine->execlists.queue) != rb); while (rb) { struct i915_priolist *p = rb_entry(rb, typeof(*p), node); struct drm_i915_gem_request *rq, *rn; list_for_each_entry_safe(rq, rn, &p->requests, priotree.link) { /* * 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->ctx, last->ctx)) { /* * If we are on the second port and cannot * combine this request with the last, then we * are done. */ if (port != engine->execlists.port) { __list_del_many(&p->requests, &rq->priotree.link); 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->ctx) || ctx_single_port_submission(rq->ctx)) { __list_del_many(&p->requests, &rq->priotree.link); goto done; } GEM_BUG_ON(last->ctx == rq->ctx); if (submit) port_assign(port, last); port++; } INIT_LIST_HEAD(&rq->priotree.link); rq->priotree.priority = INT_MAX; __i915_gem_request_submit(rq); trace_i915_gem_request_in(rq, port_index(port, engine)); last = rq; submit = true; } rb = rb_next(rb); rb_erase(&p->node, &engine->execlists.queue); INIT_LIST_HEAD(&p->requests); if (p->priority != I915_PRIORITY_NORMAL) kmem_cache_free(engine->i915->priorities, p); } done: engine->execlists.first = rb; if (submit) port_assign(port, last); spin_unlock_irq(&engine->timeline->lock); if (submit) execlists_submit_ports(engine); } static void execlists_cancel_requests(struct intel_engine_cs *engine) { struct intel_engine_execlists * const execlists = &engine->execlists; struct execlist_port *port = execlists->port; struct drm_i915_gem_request *rq, *rn; struct rb_node *rb; unsigned long flags; unsigned long n; spin_lock_irqsave(&engine->timeline->lock, flags); /* Cancel the requests on the HW and clear the ELSP tracker. */ for (n = 0; n < ARRAY_SIZE(execlists->port); n++) i915_gem_request_put(port_request(&port[n])); memset(execlists->port, 0, sizeof(execlists->port)); /* Mark all executing requests as skipped. */ list_for_each_entry(rq, &engine->timeline->requests, link) { GEM_BUG_ON(!rq->global_seqno); if (!i915_gem_request_completed(rq)) dma_fence_set_error(&rq->fence, -EIO); } /* Flush the queued requests to the timeline list (for retiring). */ rb = execlists->first; while (rb) { struct i915_priolist *p = rb_entry(rb, typeof(*p), node); list_for_each_entry_safe(rq, rn, &p->requests, priotree.link) { INIT_LIST_HEAD(&rq->priotree.link); rq->priotree.priority = INT_MAX; dma_fence_set_error(&rq->fence, -EIO); __i915_gem_request_submit(rq); } rb = rb_next(rb); rb_erase(&p->node, &execlists->queue); INIT_LIST_HEAD(&p->requests); if (p->priority != I915_PRIORITY_NORMAL) kmem_cache_free(engine->i915->priorities, p); } /* Remaining _unready_ requests will be nop'ed when submitted */ execlists->queue = RB_ROOT; execlists->first = NULL; GEM_BUG_ON(port_isset(&port[0])); /* * The port is checked prior to scheduling a tasklet, but * just in case we have suspended the tasklet to do the * wedging make sure that when it wakes, it decides there * is no work to do by clearing the irq_posted bit. */ clear_bit(ENGINE_IRQ_EXECLIST, &engine->irq_posted); spin_unlock_irqrestore(&engine->timeline->lock, flags); } static bool execlists_elsp_ready(const struct intel_engine_cs *engine) { const struct execlist_port *port = engine->execlists.port; return port_count(&port[0]) + port_count(&port[1]) < 2; } /* * Check the unread Context Status Buffers and manage the submission of new * contexts to the ELSP accordingly. */ static void intel_lrc_irq_handler(unsigned long data) { struct intel_engine_cs * const engine = (struct intel_engine_cs *)data; struct intel_engine_execlists * const execlists = &engine->execlists; struct execlist_port *port = execlists->port; struct drm_i915_private *dev_priv = engine->i915; /* 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(!dev_priv->gt.awake); intel_uncore_forcewake_get(dev_priv, execlists->fw_domains); /* Prefer doing test_and_clear_bit() as a two stage operation to avoid * imposing the cost of a locked atomic transaction when submitting a * new request (outside of the context-switch interrupt). */ while (test_bit(ENGINE_IRQ_EXECLIST, &engine->irq_posted)) { /* The HWSP contains a (cacheable) mirror of the CSB */ const u32 *buf = &engine->status_page.page_addr[I915_HWS_CSB_BUF0_INDEX]; unsigned int head, tail; /* However GVT emulation depends upon intercepting CSB mmio */ if (unlikely(execlists->csb_use_mmio)) { buf = (u32 * __force) (dev_priv->regs + i915_mmio_reg_offset(RING_CONTEXT_STATUS_BUF_LO(engine, 0))); execlists->csb_head = -1; /* force mmio read of CSB ptrs */ } /* The write will be ordered by the uncached read (itself * a memory barrier), so we do not need another in the form * of a locked instruction. The race between the interrupt * handler and the split test/clear is harmless as we order * our clear before the CSB read. If the interrupt arrived * first between the test and the clear, we read the updated * CSB and clear the bit. If the interrupt arrives as we read * the CSB or later (i.e. after we had cleared the bit) the bit * is set and we do a new loop. */ __clear_bit(ENGINE_IRQ_EXECLIST, &engine->irq_posted); if (unlikely(execlists->csb_head == -1)) { /* following a reset */ head = readl(dev_priv->regs + i915_mmio_reg_offset(RING_CONTEXT_STATUS_PTR(engine))); tail = GEN8_CSB_WRITE_PTR(head); head = GEN8_CSB_READ_PTR(head); execlists->csb_head = head; } else { const int write_idx = intel_hws_csb_write_index(dev_priv) - I915_HWS_CSB_BUF0_INDEX; head = execlists->csb_head; tail = READ_ONCE(buf[write_idx]); } while (head != tail) { struct drm_i915_gem_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. */ status = READ_ONCE(buf[2 * head]); /* maybe mmio! */ if (!(status & GEN8_CTX_STATUS_COMPLETED_MASK)) continue; /* Check the context/desc id for this event matches */ GEM_DEBUG_BUG_ON(buf[2 * head + 1] != port->context_id); rq = port_unpack(port, &count); GEM_BUG_ON(count == 0); if (--count == 0) { GEM_BUG_ON(status & GEN8_CTX_STATUS_PREEMPTED); GEM_BUG_ON(!i915_gem_request_completed(rq)); execlists_context_status_change(rq, INTEL_CONTEXT_SCHEDULE_OUT); trace_i915_gem_request_out(rq); i915_gem_request_put(rq); port[0] = port[1]; memset(&port[1], 0, sizeof(port[1])); } else { port_set(port, port_pack(rq, count)); } /* After the final element, the hw should be idle */ GEM_BUG_ON(port_count(port) == 0 && !(status & GEN8_CTX_STATUS_ACTIVE_IDLE)); } if (head != execlists->csb_head) { execlists->csb_head = head; writel(_MASKED_FIELD(GEN8_CSB_READ_PTR_MASK, head << 8), dev_priv->regs + i915_mmio_reg_offset(RING_CONTEXT_STATUS_PTR(engine))); } } if (execlists_elsp_ready(engine)) execlists_dequeue(engine); intel_uncore_forcewake_put(dev_priv, execlists->fw_domains); } static void insert_request(struct intel_engine_cs *engine, struct i915_priotree *pt, int prio) { struct i915_priolist *p = lookup_priolist(engine, pt, prio); list_add_tail(&pt->link, &ptr_mask_bits(p, 1)->requests); if (ptr_unmask_bits(p, 1) && execlists_elsp_ready(engine)) tasklet_hi_schedule(&engine->execlists.irq_tasklet); } static void execlists_submit_request(struct drm_i915_gem_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); insert_request(engine, &request->priotree, request->priotree.priority); GEM_BUG_ON(!engine->execlists.first); GEM_BUG_ON(list_empty(&request->priotree.link)); spin_unlock_irqrestore(&engine->timeline->lock, flags); } static struct intel_engine_cs * pt_lock_engine(struct i915_priotree *pt, struct intel_engine_cs *locked) { struct intel_engine_cs *engine = container_of(pt, struct drm_i915_gem_request, priotree)->engine; GEM_BUG_ON(!locked); if (engine != locked) { spin_unlock(&locked->timeline->lock); spin_lock(&engine->timeline->lock); } return engine; } static void execlists_schedule(struct drm_i915_gem_request *request, int prio) { struct intel_engine_cs *engine; struct i915_dependency *dep, *p; struct i915_dependency stack; LIST_HEAD(dfs); if (prio <= READ_ONCE(request->priotree.priority)) return; /* Need BKL in order to use the temporary link inside i915_dependency */ lockdep_assert_held(&request->i915->drm.struct_mutex); stack.signaler = &request->priotree; list_add(&stack.dfs_link, &dfs); /* Recursively bump all dependent priorities to match the new request. * * A naive approach would be to use recursion: * static void update_priorities(struct i915_priotree *pt, prio) { * list_for_each_entry(dep, &pt->signalers_list, signal_link) * update_priorities(dep->signal, prio) * insert_request(pt); * } * but that may have unlimited recursion depth and so runs a very * real risk of overunning the kernel stack. Instead, we build * a flat list of all dependencies starting with the current request. * As we walk the list of dependencies, we add all of its dependencies * to the end of the list (this may include an already visited * request) and continue to walk onwards onto the new dependencies. The * end result is a topological list of requests in reverse order, the * last element in the list is the request we must execute first. */ list_for_each_entry_safe(dep, p, &dfs, dfs_link) { struct i915_priotree *pt = dep->signaler; /* Within an engine, there can be no cycle, but we may * refer to the same dependency chain multiple times * (redundant dependencies are not eliminated) and across * engines. */ list_for_each_entry(p, &pt->signalers_list, signal_link) { GEM_BUG_ON(p->signaler->priority < pt->priority); if (prio > READ_ONCE(p->signaler->priority)) list_move_tail(&p->dfs_link, &dfs); } list_safe_reset_next(dep, p, dfs_link); } /* If we didn't need to bump any existing priorities, and we haven't * yet submitted this request (i.e. there is no potential race with * execlists_submit_request()), we can set our own priority and skip * acquiring the engine locks. */ if (request->priotree.priority == INT_MIN) { GEM_BUG_ON(!list_empty(&request->priotree.link)); request->priotree.priority = prio; if (stack.dfs_link.next == stack.dfs_link.prev) return; __list_del_entry(&stack.dfs_link); } engine = request->engine; spin_lock_irq(&engine->timeline->lock); /* Fifo and depth-first replacement ensure our deps execute before us */ list_for_each_entry_safe_reverse(dep, p, &dfs, dfs_link) { struct i915_priotree *pt = dep->signaler; INIT_LIST_HEAD(&dep->dfs_link); engine = pt_lock_engine(pt, engine); if (prio <= pt->priority) continue; pt->priority = prio; if (!list_empty(&pt->link)) { __list_del_entry(&pt->link); insert_request(engine, pt, prio); } } spin_unlock_irq(&engine->timeline->lock); /* XXX Do we need to preempt to make room for us and our deps? */ } static struct intel_ring * execlists_context_pin(struct intel_engine_cs *engine, struct i915_gem_context *ctx) { struct intel_context *ce = &ctx->engine[engine->id]; unsigned int flags; void *vaddr; int ret; lockdep_assert_held(&ctx->i915->drm.struct_mutex); if (likely(ce->pin_count++)) goto out; GEM_BUG_ON(!ce->pin_count); /* no overflow please! */ if (!ce->state) { ret = execlists_context_deferred_alloc(ctx, engine); if (ret) goto err; } GEM_BUG_ON(!ce->state); flags = PIN_GLOBAL | PIN_HIGH; if (ctx->ggtt_offset_bias) flags |= PIN_OFFSET_BIAS | ctx->ggtt_offset_bias; ret = i915_vma_pin(ce->state, 0, GEN8_LR_CONTEXT_ALIGN, flags); if (ret) goto err; vaddr = i915_gem_object_pin_map(ce->state->obj, I915_MAP_WB); if (IS_ERR(vaddr)) { ret = PTR_ERR(vaddr); goto unpin_vma; } ret = intel_ring_pin(ce->ring, ctx->i915, ctx->ggtt_offset_bias); if (ret) goto unpin_map; intel_lr_context_descriptor_update(ctx, engine); ce->lrc_reg_state = vaddr + LRC_STATE_PN * PAGE_SIZE; ce->lrc_reg_state[CTX_RING_BUFFER_START+1] = i915_ggtt_offset(ce->ring->vma); ce->state->obj->mm.dirty = true; i915_gem_context_get(ctx); out: return 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 void execlists_context_unpin(struct intel_engine_cs *engine, struct i915_gem_context *ctx) { struct intel_context *ce = &ctx->engine[engine->id]; lockdep_assert_held(&ctx->i915->drm.struct_mutex); GEM_BUG_ON(ce->pin_count == 0); if (--ce->pin_count) return; intel_ring_unpin(ce->ring); i915_gem_object_unpin_map(ce->state->obj); i915_vma_unpin(ce->state); i915_gem_context_put(ctx); } static int execlists_request_alloc(struct drm_i915_gem_request *request) { struct intel_engine_cs *engine = request->engine; struct intel_context *ce = &request->ctx->engine[engine->id]; u32 *cs; int ret; GEM_BUG_ON(!ce->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; cs = intel_ring_begin(request, 0); if (IS_ERR(cs)) return PTR_ERR(cs); if (!ce->initialised) { ret = engine->init_context(request); if (ret) return ret; ce->initialised = true; } /* 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. */ 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) { *batch++ = MI_STORE_REGISTER_MEM_GEN8 | MI_SRM_LRM_GLOBAL_GTT; *batch++ = i915_mmio_reg_offset(GEN8_L3SQCREG4); *batch++ = i915_ggtt_offset(engine->scratch) + 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_ggtt_offset(engine->scratch) + 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_ggtt_offset(engine->scratch) + 2 * CACHELINE_BYTES); /* 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; } /* * This batch is started immediately after indirect_ctx batch. Since we ensure * that indirect_ctx ends on a cacheline this batch is aligned automatically. * * The number of DWORDS written are returned using this field. * * This batch is terminated with MI_BATCH_BUFFER_END and so we need not add padding * to align it with cacheline as padding after MI_BATCH_BUFFER_END is redundant. */ static u32 *gen8_init_perctx_bb(struct intel_engine_cs *engine, u32 *batch) { /* WaDisableCtxRestoreArbitration:bdw,chv */ *batch++ = MI_ARB_ON_OFF | MI_ARB_ENABLE; *batch++ = MI_BATCH_BUFFER_END; return batch; } static u32 *gen9_init_indirectctx_bb(struct intel_engine_cs *engine, u32 *batch) { /* WaFlushCoherentL3CacheLinesAtContextSwitch:skl,bxt,glk */ batch = gen8_emit_flush_coherentl3_wa(engine, batch); /* WaDisableGatherAtSetShaderCommonSlice:skl,bxt,kbl,glk */ *batch++ = MI_LOAD_REGISTER_IMM(1); *batch++ = i915_mmio_reg_offset(COMMON_SLICE_CHICKEN2); *batch++ = _MASKED_BIT_DISABLE( GEN9_DISABLE_GATHER_AT_SET_SHADER_COMMON_SLICE); *batch++ = MI_NOOP; /* WaClearSlmSpaceAtContextSwitch:kbl */ /* Actual scratch location is at 128 bytes offset */ if (IS_KBL_REVID(engine->i915, 0, KBL_REVID_A0)) { batch = gen8_emit_pipe_control(batch, PIPE_CONTROL_FLUSH_L3 | PIPE_CONTROL_GLOBAL_GTT_IVB | PIPE_CONTROL_CS_STALL | PIPE_CONTROL_QW_WRITE, i915_ggtt_offset(engine->scratch) + 2 * CACHELINE_BYTES); } /* 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; } /* Pad to end of cacheline */ while ((unsigned long)batch % CACHELINE_BYTES) *batch++ = MI_NOOP; return batch; } static u32 *gen9_init_perctx_bb(struct intel_engine_cs *engine, u32 *batch) { *batch++ = MI_BATCH_BUFFER_END; 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.base, NULL); if (IS_ERR(vma)) { err = PTR_ERR(vma); goto err; } err = i915_vma_pin(vma, 0, PAGE_SIZE, 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); } 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 (WARN_ON(engine->id != RCS || !engine->scratch)) return -EINVAL; switch (INTEL_GEN(engine->i915)) { case 10: return 0; case 9: wa_bb_fn[0] = gen9_init_indirectctx_bb; wa_bb_fn[1] = gen9_init_perctx_bb; break; case 8: wa_bb_fn[0] = gen8_init_indirectctx_bb; wa_bb_fn[1] = gen8_init_perctx_bb; 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 (WARN_ON(!IS_ALIGNED(wa_bb[i]->offset, CACHELINE_BYTES))) { ret = -EINVAL; break; } 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 u8 gtiir[] = { [RCS] = 0, [BCS] = 0, [VCS] = 1, [VCS2] = 1, [VECS] = 3, }; static int gen8_init_common_ring(struct intel_engine_cs *engine) { struct drm_i915_private *dev_priv = engine->i915; struct intel_engine_execlists * const execlists = &engine->execlists; int ret; ret = intel_mocs_init_engine(engine); if (ret) return ret; intel_engine_reset_breadcrumbs(engine); intel_engine_init_hangcheck(engine); I915_WRITE(RING_HWSTAM(engine->mmio_base), 0xffffffff); I915_WRITE(RING_MODE_GEN7(engine), _MASKED_BIT_ENABLE(GFX_RUN_LIST_ENABLE)); I915_WRITE(RING_HWS_PGA(engine->mmio_base), engine->status_page.ggtt_offset); POSTING_READ(RING_HWS_PGA(engine->mmio_base)); DRM_DEBUG_DRIVER("Execlists enabled for %s\n", engine->name); GEM_BUG_ON(engine->id >= ARRAY_SIZE(gtiir)); /* * Clear any pending interrupt state. * * We do it twice out of paranoia that some of the IIR are double * buffered, and if we only reset it once there may still be * an interrupt pending. */ I915_WRITE(GEN8_GT_IIR(gtiir[engine->id]), GT_CONTEXT_SWITCH_INTERRUPT << engine->irq_shift); I915_WRITE(GEN8_GT_IIR(gtiir[engine->id]), GT_CONTEXT_SWITCH_INTERRUPT << engine->irq_shift); clear_bit(ENGINE_IRQ_EXECLIST, &engine->irq_posted); execlists->csb_head = -1; /* After a GPU reset, we may have requests to replay */ if (!i915_modparams.enable_guc_submission && execlists->first) tasklet_schedule(&execlists->irq_tasklet); return 0; } static int gen8_init_render_ring(struct intel_engine_cs *engine) { struct drm_i915_private *dev_priv = engine->i915; int ret; ret = gen8_init_common_ring(engine); if (ret) return ret; /* We need to disable the AsyncFlip performance optimisations in order * to use MI_WAIT_FOR_EVENT within the CS. It should already be * programmed to '1' on all products. * * WaDisableAsyncFlipPerfMode:snb,ivb,hsw,vlv,bdw,chv */ I915_WRITE(MI_MODE, _MASKED_BIT_ENABLE(ASYNC_FLIP_PERF_DISABLE)); I915_WRITE(INSTPM, _MASKED_BIT_ENABLE(INSTPM_FORCE_ORDERING)); return init_workarounds_ring(engine); } static int gen9_init_render_ring(struct intel_engine_cs *engine) { int ret; ret = gen8_init_common_ring(engine); if (ret) return ret; return init_workarounds_ring(engine); } static void reset_common_ring(struct intel_engine_cs *engine, struct drm_i915_gem_request *request) { struct intel_engine_execlists * const execlists = &engine->execlists; struct execlist_port *port = execlists->port; struct drm_i915_gem_request *rq, *rn; struct intel_context *ce; unsigned long flags; unsigned int n; 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. */ for (n = 0; n < ARRAY_SIZE(execlists->port); n++) i915_gem_request_put(port_request(&port[n])); memset(execlists->port, 0, sizeof(execlists->port)); /* Push back any incomplete requests for replay after the reset. */ list_for_each_entry_safe_reverse(rq, rn, &engine->timeline->requests, link) { struct i915_priolist *p; if (i915_gem_request_completed(rq)) break; __i915_gem_request_unsubmit(rq); p = lookup_priolist(engine, &rq->priotree, rq->priotree.priority); list_add(&rq->priotree.link, &ptr_mask_bits(p, 1)->requests); } spin_unlock_irqrestore(&engine->timeline->lock, flags); /* 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. */ if (!request || request->fence.error != -EIO) return; /* 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. */ ce = &request->ctx->engine[engine->id]; execlists_init_reg_state(ce->lrc_reg_state, request->ctx, engine, ce->ring); /* Move the RING_HEAD onto the breadcrumb, past the hanging batch */ ce->lrc_reg_state[CTX_RING_BUFFER_START+1] = i915_ggtt_offset(ce->ring->vma); ce->lrc_reg_state[CTX_RING_HEAD+1] = request->postfix; request->ring->head = request->postfix; intel_ring_update_space(request->ring); /* Reset WaIdleLiteRestore:bdw,skl as well */ request->tail = intel_ring_wrap(request->ring, request->wa_tail - WA_TAIL_DWORDS*sizeof(u32)); assert_ring_tail_valid(request->ring, request->tail); } static int intel_logical_ring_emit_pdps(struct drm_i915_gem_request *req) { struct i915_hw_ppgtt *ppgtt = req->ctx->ppgtt; struct intel_engine_cs *engine = req->engine; const int num_lri_cmds = GEN8_3LVL_PDPES * 2; u32 *cs; int i; cs = intel_ring_begin(req, num_lri_cmds * 2 + 2); if (IS_ERR(cs)) return PTR_ERR(cs); *cs++ = MI_LOAD_REGISTER_IMM(num_lri_cmds); for (i = GEN8_3LVL_PDPES - 1; i >= 0; 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(req, cs); return 0; } static int gen8_emit_bb_start(struct drm_i915_gem_request *req, u64 offset, u32 len, const unsigned int flags) { u32 *cs; int ret; /* Don't rely in hw updating PDPs, specially in lite-restore. * Ideally, we should set Force PD Restore in ctx descriptor, * but we can't. Force Restore would be a second option, but * it is unsafe in case of lite-restore (because the ctx is * not idle). PML4 is allocated during ppgtt init so this is * not needed in 48-bit.*/ if (req->ctx->ppgtt && (intel_engine_flag(req->engine) & req->ctx->ppgtt->pd_dirty_rings) && !i915_vm_is_48bit(&req->ctx->ppgtt->base) && !intel_vgpu_active(req->i915)) { ret = intel_logical_ring_emit_pdps(req); if (ret) return ret; req->ctx->ppgtt->pd_dirty_rings &= ~intel_engine_flag(req->engine); } cs = intel_ring_begin(req, 4); if (IS_ERR(cs)) return PTR_ERR(cs); /* FIXME(BDW): Address space and security selectors. */ *cs++ = MI_BATCH_BUFFER_START_GEN8 | (flags & I915_DISPATCH_SECURE ? 0 : BIT(8)) | (flags & I915_DISPATCH_RS ? MI_BATCH_RESOURCE_STREAMER : 0); *cs++ = lower_32_bits(offset); *cs++ = upper_32_bits(offset); *cs++ = MI_NOOP; intel_ring_advance(req, 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 drm_i915_gem_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->id == VCS) 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 drm_i915_gem_request *request, u32 mode) { struct intel_engine_cs *engine = request->engine; u32 scratch_addr = i915_ggtt_offset(engine->scratch) + 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_GEN9(request->i915)) 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 void gen8_emit_wa_tail(struct drm_i915_gem_request *request, u32 *cs) { *cs++ = MI_NOOP; *cs++ = MI_NOOP; request->wa_tail = intel_ring_offset(request, cs); } static void gen8_emit_breadcrumb(struct drm_i915_gem_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++ = (MI_FLUSH_DW + 1) | MI_FLUSH_DW_OP_STOREDW; *cs++ = intel_hws_seqno_address(request->engine) | MI_FLUSH_DW_USE_GTT; *cs++ = 0; *cs++ = request->global_seqno; *cs++ = MI_USER_INTERRUPT; *cs++ = MI_NOOP; request->tail = intel_ring_offset(request, cs); assert_ring_tail_valid(request->ring, request->tail); gen8_emit_wa_tail(request, cs); } static const int gen8_emit_breadcrumb_sz = 6 + WA_TAIL_DWORDS; static void gen8_emit_breadcrumb_render(struct drm_i915_gem_request *request, u32 *cs) { /* We're using qword write, seqno should be aligned to 8 bytes. */ BUILD_BUG_ON(I915_GEM_HWS_INDEX & 1); /* w/a for post sync ops following a GPGPU operation we * need a prior CS_STALL, which is emitted by the flush * following the batch. */ *cs++ = GFX_OP_PIPE_CONTROL(6); *cs++ = PIPE_CONTROL_GLOBAL_GTT_IVB | PIPE_CONTROL_CS_STALL | PIPE_CONTROL_QW_WRITE; *cs++ = intel_hws_seqno_address(request->engine); *cs++ = 0; *cs++ = request->global_seqno; /* We're thrashing one dword of HWS. */ *cs++ = 0; *cs++ = MI_USER_INTERRUPT; *cs++ = MI_NOOP; request->tail = intel_ring_offset(request, cs); assert_ring_tail_valid(request->ring, request->tail); gen8_emit_wa_tail(request, cs); } static const int gen8_emit_breadcrumb_render_sz = 8 + WA_TAIL_DWORDS; static int gen8_init_rcs_context(struct drm_i915_gem_request *req) { int ret; ret = intel_ring_workarounds_emit(req); if (ret) return ret; ret = intel_rcs_context_init_mocs(req); /* * 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(req); } /** * 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.irq_tasklet.state))) tasklet_kill(&engine->execlists.irq_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); } static void execlists_set_default_submission(struct intel_engine_cs *engine) { engine->submit_request = execlists_submit_request; engine->cancel_requests = execlists_cancel_requests; engine->schedule = execlists_schedule; engine->execlists.irq_tasklet.func = intel_lrc_irq_handler; } 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_hw = reset_common_ring; engine->context_pin = execlists_context_pin; engine->context_unpin = execlists_context_unpin; engine->request_alloc = execlists_request_alloc; engine->emit_flush = gen8_emit_flush; engine->emit_breadcrumb = gen8_emit_breadcrumb; engine->emit_breadcrumb_sz = gen8_emit_breadcrumb_sz; engine->set_default_submission = execlists_set_default_submission; engine->irq_enable = gen8_logical_ring_enable_irq; engine->irq_disable = gen8_logical_ring_disable_irq; engine->emit_bb_start = gen8_emit_bb_start; } static inline void logical_ring_default_irqs(struct intel_engine_cs *engine) { unsigned shift = engine->irq_shift; engine->irq_enable_mask = GT_RENDER_USER_INTERRUPT << shift; engine->irq_keep_mask = GT_CONTEXT_SWITCH_INTERRUPT << shift; } static void logical_ring_setup(struct intel_engine_cs *engine) { struct drm_i915_private *dev_priv = engine->i915; enum forcewake_domains fw_domains; intel_engine_setup_common(engine); /* Intentionally left blank. */ engine->buffer = NULL; fw_domains = intel_uncore_forcewake_for_reg(dev_priv, RING_ELSP(engine), FW_REG_WRITE); fw_domains |= intel_uncore_forcewake_for_reg(dev_priv, RING_CONTEXT_STATUS_PTR(engine), FW_REG_READ | FW_REG_WRITE); fw_domains |= intel_uncore_forcewake_for_reg(dev_priv, RING_CONTEXT_STATUS_BUF_BASE(engine), FW_REG_READ); engine->execlists.fw_domains = fw_domains; tasklet_init(&engine->execlists.irq_tasklet, intel_lrc_irq_handler, (unsigned long)engine); logical_ring_default_vfuncs(engine); logical_ring_default_irqs(engine); } static int logical_ring_init(struct intel_engine_cs *engine) { int ret; ret = intel_engine_init_common(engine); if (ret) goto error; return 0; error: intel_logical_ring_cleanup(engine); return ret; } int logical_render_ring_init(struct intel_engine_cs *engine) { struct drm_i915_private *dev_priv = engine->i915; int ret; logical_ring_setup(engine); if (HAS_L3_DPF(dev_priv)) engine->irq_keep_mask |= GT_RENDER_L3_PARITY_ERROR_INTERRUPT; /* Override some for render ring. */ if (INTEL_GEN(dev_priv) >= 9) engine->init_hw = gen9_init_render_ring; else engine->init_hw = gen8_init_render_ring; engine->init_context = gen8_init_rcs_context; engine->emit_flush = gen8_emit_flush_render; engine->emit_breadcrumb = gen8_emit_breadcrumb_render; engine->emit_breadcrumb_sz = gen8_emit_breadcrumb_render_sz; ret = intel_engine_create_scratch(engine, PAGE_SIZE); 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); } return logical_ring_init(engine); } int logical_xcs_ring_init(struct intel_engine_cs *engine) { logical_ring_setup(engine); return logical_ring_init(engine); } static u32 make_rpcs(struct drm_i915_private *dev_priv) { 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; /* * 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 (INTEL_INFO(dev_priv)->sseu.has_slice_pg) { rpcs |= GEN8_RPCS_S_CNT_ENABLE; rpcs |= hweight8(INTEL_INFO(dev_priv)->sseu.slice_mask) << GEN8_RPCS_S_CNT_SHIFT; rpcs |= GEN8_RPCS_ENABLE; } if (INTEL_INFO(dev_priv)->sseu.has_subslice_pg) { rpcs |= GEN8_RPCS_SS_CNT_ENABLE; rpcs |= hweight8(INTEL_INFO(dev_priv)->sseu.subslice_mask) << GEN8_RPCS_SS_CNT_SHIFT; rpcs |= GEN8_RPCS_ENABLE; } if (INTEL_INFO(dev_priv)->sseu.has_eu_pg) { rpcs |= INTEL_INFO(dev_priv)->sseu.eu_per_subslice << GEN8_RPCS_EU_MIN_SHIFT; rpcs |= INTEL_INFO(dev_priv)->sseu.eu_per_subslice << GEN8_RPCS_EU_MAX_SHIFT; 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 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; struct i915_hw_ppgtt *ppgtt = ctx->ppgtt ?: dev_priv->mm.aliasing_ppgtt; u32 base = engine->mmio_base; bool rcs = engine->id == RCS; /* 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_ENABLE(CTX_CTRL_INHIBIT_SYN_CTX_SWITCH | CTX_CTRL_ENGINE_CTX_RESTORE_INHIBIT | (HAS_RESOURCE_STREAMER(dev_priv) ? CTX_CTRL_RS_CTX_ENABLE : 0))); 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) { CTX_REG(regs, CTX_BB_PER_CTX_PTR, RING_BB_PER_CTX_PTR(base), 0); 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 (engine->wa_ctx.vma) { struct i915_ctx_workarounds *wa_ctx = &engine->wa_ctx; 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; 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 (ppgtt && i915_vm_is_48bit(&ppgtt->base)) { /* 64b PPGTT (48bit canonical) * PDP0_DESCRIPTOR contains the base address to PML4 and * other PDP Descriptors are ignored. */ ASSIGN_CTX_PML4(ppgtt, regs); } 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, make_rpcs(dev_priv)); i915_oa_init_reg_state(engine, ctx, regs); } } 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; 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; /* The second page of the context object contains some fields which must * be set up prior to the first execution. */ execlists_init_reg_state(vaddr + LRC_STATE_PN * PAGE_SIZE, ctx, engine, ring); i915_gem_object_unpin_map(ctx_obj); return 0; } static int execlists_context_deferred_alloc(struct i915_gem_context *ctx, struct intel_engine_cs *engine) { struct drm_i915_gem_object *ctx_obj; struct intel_context *ce = &ctx->engine[engine->id]; struct i915_vma *vma; uint32_t context_size; struct intel_ring *ring; int ret; WARN_ON(ce->state); 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)) { DRM_DEBUG_DRIVER("Alloc LRC backing obj failed.\n"); return PTR_ERR(ctx_obj); } vma = i915_vma_instance(ctx_obj, &ctx->i915->ggtt.base, NULL); if (IS_ERR(vma)) { ret = PTR_ERR(vma); goto error_deref_obj; } ring = intel_engine_create_ring(engine, ctx->ring_size); 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; ce->initialised |= engine->init_context == NULL; 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 *dev_priv) { 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, &dev_priv->contexts.list, link) { for_each_engine(engine, dev_priv, id) { struct intel_context *ce = &ctx->engine[engine->id]; u32 *reg; if (!ce->state) continue; reg = i915_gem_object_pin_map(ce->state->obj, I915_MAP_WB); if (WARN_ON(IS_ERR(reg))) continue; reg += LRC_STATE_PN * PAGE_SIZE / sizeof(*reg); reg[CTX_RING_HEAD+1] = 0; reg[CTX_RING_TAIL+1] = 0; ce->state->obj->mm.dirty = true; i915_gem_object_unpin_map(ce->state->obj); intel_ring_reset(ce->ring, 0); } } }