#ifndef _INTEL_RINGBUFFER_H_ #define _INTEL_RINGBUFFER_H_ #include #include "i915_gem_batch_pool.h" #include "i915_gem_request.h" #include "i915_gem_timeline.h" #define I915_CMD_HASH_ORDER 9 /* Early gen2 devices have a cacheline of just 32 bytes, using 64 is overkill, * but keeps the logic simple. Indeed, the whole purpose of this macro is just * to give some inclination as to some of the magic values used in the various * workarounds! */ #define CACHELINE_BYTES 64 #define CACHELINE_DWORDS (CACHELINE_BYTES / sizeof(uint32_t)) /* * Gen2 BSpec "1. Programming Environment" / 1.4.4.6 "Ring Buffer Use" * Gen3 BSpec "vol1c Memory Interface Functions" / 2.3.4.5 "Ring Buffer Use" * Gen4+ BSpec "vol1c Memory Interface and Command Stream" / 5.3.4.5 "Ring Buffer Use" * * "If the Ring Buffer Head Pointer and the Tail Pointer are on the same * cacheline, the Head Pointer must not be greater than the Tail * Pointer." */ #define I915_RING_FREE_SPACE 64 struct intel_hw_status_page { struct i915_vma *vma; u32 *page_addr; u32 ggtt_offset; }; #define I915_READ_TAIL(engine) I915_READ(RING_TAIL((engine)->mmio_base)) #define I915_WRITE_TAIL(engine, val) I915_WRITE(RING_TAIL((engine)->mmio_base), val) #define I915_READ_START(engine) I915_READ(RING_START((engine)->mmio_base)) #define I915_WRITE_START(engine, val) I915_WRITE(RING_START((engine)->mmio_base), val) #define I915_READ_HEAD(engine) I915_READ(RING_HEAD((engine)->mmio_base)) #define I915_WRITE_HEAD(engine, val) I915_WRITE(RING_HEAD((engine)->mmio_base), val) #define I915_READ_CTL(engine) I915_READ(RING_CTL((engine)->mmio_base)) #define I915_WRITE_CTL(engine, val) I915_WRITE(RING_CTL((engine)->mmio_base), val) #define I915_READ_IMR(engine) I915_READ(RING_IMR((engine)->mmio_base)) #define I915_WRITE_IMR(engine, val) I915_WRITE(RING_IMR((engine)->mmio_base), val) #define I915_READ_MODE(engine) I915_READ(RING_MI_MODE((engine)->mmio_base)) #define I915_WRITE_MODE(engine, val) I915_WRITE(RING_MI_MODE((engine)->mmio_base), val) /* seqno size is actually only a uint32, but since we plan to use MI_FLUSH_DW to * do the writes, and that must have qw aligned offsets, simply pretend it's 8b. */ #define gen8_semaphore_seqno_size sizeof(uint64_t) #define GEN8_SEMAPHORE_OFFSET(__from, __to) \ (((__from) * I915_NUM_ENGINES + (__to)) * gen8_semaphore_seqno_size) #define GEN8_SIGNAL_OFFSET(__ring, to) \ (dev_priv->semaphore->node.start + \ GEN8_SEMAPHORE_OFFSET((__ring)->id, (to))) #define GEN8_WAIT_OFFSET(__ring, from) \ (dev_priv->semaphore->node.start + \ GEN8_SEMAPHORE_OFFSET(from, (__ring)->id)) enum intel_engine_hangcheck_action { ENGINE_IDLE = 0, ENGINE_WAIT, ENGINE_ACTIVE_SEQNO, ENGINE_ACTIVE_HEAD, ENGINE_ACTIVE_SUBUNITS, ENGINE_WAIT_KICK, ENGINE_DEAD, }; static inline const char * hangcheck_action_to_str(const enum intel_engine_hangcheck_action a) { switch (a) { case ENGINE_IDLE: return "idle"; case ENGINE_WAIT: return "wait"; case ENGINE_ACTIVE_SEQNO: return "active seqno"; case ENGINE_ACTIVE_HEAD: return "active head"; case ENGINE_ACTIVE_SUBUNITS: return "active subunits"; case ENGINE_WAIT_KICK: return "wait kick"; case ENGINE_DEAD: return "dead"; } return "unknown"; } #define I915_MAX_SLICES 3 #define I915_MAX_SUBSLICES 3 #define instdone_slice_mask(dev_priv__) \ (INTEL_GEN(dev_priv__) == 7 ? \ 1 : INTEL_INFO(dev_priv__)->sseu.slice_mask) #define instdone_subslice_mask(dev_priv__) \ (INTEL_GEN(dev_priv__) == 7 ? \ 1 : INTEL_INFO(dev_priv__)->sseu.subslice_mask) #define for_each_instdone_slice_subslice(dev_priv__, slice__, subslice__) \ for ((slice__) = 0, (subslice__) = 0; \ (slice__) < I915_MAX_SLICES; \ (subslice__) = ((subslice__) + 1) < I915_MAX_SUBSLICES ? (subslice__) + 1 : 0, \ (slice__) += ((subslice__) == 0)) \ for_each_if((BIT(slice__) & instdone_slice_mask(dev_priv__)) && \ (BIT(subslice__) & instdone_subslice_mask(dev_priv__))) struct intel_instdone { u32 instdone; /* The following exist only in the RCS engine */ u32 slice_common; u32 sampler[I915_MAX_SLICES][I915_MAX_SUBSLICES]; u32 row[I915_MAX_SLICES][I915_MAX_SUBSLICES]; }; struct intel_engine_hangcheck { u64 acthd; u32 seqno; enum intel_engine_hangcheck_action action; unsigned long action_timestamp; int deadlock; struct intel_instdone instdone; bool stalled; }; struct intel_ring { struct i915_vma *vma; void *vaddr; struct intel_engine_cs *engine; struct list_head request_list; u32 head; u32 tail; int space; int size; int effective_size; /** We track the position of the requests in the ring buffer, and * when each is retired we increment last_retired_head as the GPU * must have finished processing the request and so we know we * can advance the ringbuffer up to that position. * * last_retired_head is set to -1 after the value is consumed so * we can detect new retirements. */ u32 last_retired_head; }; struct i915_gem_context; struct drm_i915_reg_table; /* * we use a single page to load ctx workarounds so all of these * values are referred in terms of dwords * * struct i915_wa_ctx_bb: * offset: specifies batch starting position, also helpful in case * if we want to have multiple batches at different offsets based on * some criteria. It is not a requirement at the moment but provides * an option for future use. * size: size of the batch in DWORDS */ struct i915_ctx_workarounds { struct i915_wa_ctx_bb { u32 offset; u32 size; } indirect_ctx, per_ctx; struct i915_vma *vma; }; struct drm_i915_gem_request; struct intel_render_state; struct intel_engine_cs { struct drm_i915_private *i915; const char *name; enum intel_engine_id { RCS = 0, BCS, VCS, VCS2, /* Keep instances of the same type engine together. */ VECS } id; #define _VCS(n) (VCS + (n)) unsigned int exec_id; enum intel_engine_hw_id { RCS_HW = 0, VCS_HW, BCS_HW, VECS_HW, VCS2_HW } hw_id; enum intel_engine_hw_id guc_id; /* XXX same as hw_id? */ u32 mmio_base; unsigned int irq_shift; struct intel_ring *buffer; struct intel_timeline *timeline; struct intel_render_state *render_state; /* Rather than have every client wait upon all user interrupts, * with the herd waking after every interrupt and each doing the * heavyweight seqno dance, we delegate the task (of being the * bottom-half of the user interrupt) to the first client. After * every interrupt, we wake up one client, who does the heavyweight * coherent seqno read and either goes back to sleep (if incomplete), * or wakes up all the completed clients in parallel, before then * transferring the bottom-half status to the next client in the queue. * * Compared to walking the entire list of waiters in a single dedicated * bottom-half, we reduce the latency of the first waiter by avoiding * a context switch, but incur additional coherent seqno reads when * following the chain of request breadcrumbs. Since it is most likely * that we have a single client waiting on each seqno, then reducing * the overhead of waking that client is much preferred. */ struct intel_breadcrumbs { struct task_struct __rcu *irq_seqno_bh; /* bh for interrupts */ bool irq_posted; spinlock_t lock; /* protects the lists of requests; irqsafe */ struct rb_root waiters; /* sorted by retirement, priority */ struct rb_root signals; /* sorted by retirement */ struct intel_wait *first_wait; /* oldest waiter by retirement */ struct task_struct *signaler; /* used for fence signalling */ struct drm_i915_gem_request *first_signal; struct timer_list fake_irq; /* used after a missed interrupt */ struct timer_list hangcheck; /* detect missed interrupts */ unsigned long timeout; bool irq_enabled : 1; bool rpm_wakelock : 1; } breadcrumbs; /* * A pool of objects to use as shadow copies of client batch buffers * when the command parser is enabled. Prevents the client from * modifying the batch contents after software parsing. */ struct i915_gem_batch_pool batch_pool; struct intel_hw_status_page status_page; struct i915_ctx_workarounds wa_ctx; struct i915_vma *scratch; u32 irq_keep_mask; /* always keep these interrupts */ u32 irq_enable_mask; /* bitmask to enable ring interrupt */ void (*irq_enable)(struct intel_engine_cs *engine); void (*irq_disable)(struct intel_engine_cs *engine); int (*init_hw)(struct intel_engine_cs *engine); void (*reset_hw)(struct intel_engine_cs *engine, struct drm_i915_gem_request *req); int (*context_pin)(struct intel_engine_cs *engine, struct i915_gem_context *ctx); void (*context_unpin)(struct intel_engine_cs *engine, struct i915_gem_context *ctx); int (*request_alloc)(struct drm_i915_gem_request *req); int (*init_context)(struct drm_i915_gem_request *req); int (*emit_flush)(struct drm_i915_gem_request *request, u32 mode); #define EMIT_INVALIDATE BIT(0) #define EMIT_FLUSH BIT(1) #define EMIT_BARRIER (EMIT_INVALIDATE | EMIT_FLUSH) int (*emit_bb_start)(struct drm_i915_gem_request *req, u64 offset, u32 length, unsigned int dispatch_flags); #define I915_DISPATCH_SECURE BIT(0) #define I915_DISPATCH_PINNED BIT(1) #define I915_DISPATCH_RS BIT(2) void (*emit_breadcrumb)(struct drm_i915_gem_request *req, u32 *out); int emit_breadcrumb_sz; /* Pass the request to the hardware queue (e.g. directly into * the legacy ringbuffer or to the end of an execlist). * * This is called from an atomic context with irqs disabled; must * be irq safe. */ void (*submit_request)(struct drm_i915_gem_request *req); /* Call when the priority on a request has changed and it and its * dependencies may need rescheduling. Note the request itself may * not be ready to run! * * Called under the struct_mutex. */ void (*schedule)(struct drm_i915_gem_request *request, int priority); /* Some chipsets are not quite as coherent as advertised and need * an expensive kick to force a true read of the up-to-date seqno. * However, the up-to-date seqno is not always required and the last * seen value is good enough. Note that the seqno will always be * monotonic, even if not coherent. */ void (*irq_seqno_barrier)(struct intel_engine_cs *engine); void (*cleanup)(struct intel_engine_cs *engine); /* GEN8 signal/wait table - never trust comments! * signal to signal to signal to signal to signal to * RCS VCS BCS VECS VCS2 * -------------------------------------------------------------------- * RCS | NOP (0x00) | VCS (0x08) | BCS (0x10) | VECS (0x18) | VCS2 (0x20) | * |------------------------------------------------------------------- * VCS | RCS (0x28) | NOP (0x30) | BCS (0x38) | VECS (0x40) | VCS2 (0x48) | * |------------------------------------------------------------------- * BCS | RCS (0x50) | VCS (0x58) | NOP (0x60) | VECS (0x68) | VCS2 (0x70) | * |------------------------------------------------------------------- * VECS | RCS (0x78) | VCS (0x80) | BCS (0x88) | NOP (0x90) | VCS2 (0x98) | * |------------------------------------------------------------------- * VCS2 | RCS (0xa0) | VCS (0xa8) | BCS (0xb0) | VECS (0xb8) | NOP (0xc0) | * |------------------------------------------------------------------- * * Generalization: * f(x, y) := (x->id * NUM_RINGS * seqno_size) + (seqno_size * y->id) * ie. transpose of g(x, y) * * sync from sync from sync from sync from sync from * RCS VCS BCS VECS VCS2 * -------------------------------------------------------------------- * RCS | NOP (0x00) | VCS (0x28) | BCS (0x50) | VECS (0x78) | VCS2 (0xa0) | * |------------------------------------------------------------------- * VCS | RCS (0x08) | NOP (0x30) | BCS (0x58) | VECS (0x80) | VCS2 (0xa8) | * |------------------------------------------------------------------- * BCS | RCS (0x10) | VCS (0x38) | NOP (0x60) | VECS (0x88) | VCS2 (0xb0) | * |------------------------------------------------------------------- * VECS | RCS (0x18) | VCS (0x40) | BCS (0x68) | NOP (0x90) | VCS2 (0xb8) | * |------------------------------------------------------------------- * VCS2 | RCS (0x20) | VCS (0x48) | BCS (0x70) | VECS (0x98) | NOP (0xc0) | * |------------------------------------------------------------------- * * Generalization: * g(x, y) := (y->id * NUM_RINGS * seqno_size) + (seqno_size * x->id) * ie. transpose of f(x, y) */ struct { union { #define GEN6_SEMAPHORE_LAST VECS_HW #define GEN6_NUM_SEMAPHORES (GEN6_SEMAPHORE_LAST + 1) #define GEN6_SEMAPHORES_MASK GENMASK(GEN6_SEMAPHORE_LAST, 0) struct { /* our mbox written by others */ u32 wait[GEN6_NUM_SEMAPHORES]; /* mboxes this ring signals to */ i915_reg_t signal[GEN6_NUM_SEMAPHORES]; } mbox; u64 signal_ggtt[I915_NUM_ENGINES]; }; /* AKA wait() */ int (*sync_to)(struct drm_i915_gem_request *req, struct drm_i915_gem_request *signal); u32 *(*signal)(struct drm_i915_gem_request *req, u32 *out); } semaphore; /* Execlists */ struct tasklet_struct irq_tasklet; struct execlist_port { struct drm_i915_gem_request *request; unsigned int count; } execlist_port[2]; struct rb_root execlist_queue; struct rb_node *execlist_first; unsigned int fw_domains; bool disable_lite_restore_wa; bool preempt_wa; u32 ctx_desc_template; /* Contexts are pinned whilst they are active on the GPU. The last * context executed remains active whilst the GPU is idle - the * switch away and write to the context object only occurs on the * next execution. Contexts are only unpinned on retirement of the * following request ensuring that we can always write to the object * on the context switch even after idling. Across suspend, we switch * to the kernel context and trash it as the save may not happen * before the hardware is powered down. */ struct i915_gem_context *last_retired_context; /* We track the current MI_SET_CONTEXT in order to eliminate * redudant context switches. This presumes that requests are not * reordered! Or when they are the tracking is updated along with * the emission of individual requests into the legacy command * stream (ring). */ struct i915_gem_context *legacy_active_context; struct intel_engine_hangcheck hangcheck; bool needs_cmd_parser; /* * Table of commands the command parser needs to know about * for this engine. */ DECLARE_HASHTABLE(cmd_hash, I915_CMD_HASH_ORDER); /* * Table of registers allowed in commands that read/write registers. */ const struct drm_i915_reg_table *reg_tables; int reg_table_count; /* * Returns the bitmask for the length field of the specified command. * Return 0 for an unrecognized/invalid command. * * If the command parser finds an entry for a command in the engine's * cmd_tables, it gets the command's length based on the table entry. * If not, it calls this function to determine the per-engine length * field encoding for the command (i.e. different opcode ranges use * certain bits to encode the command length in the header). */ u32 (*get_cmd_length_mask)(u32 cmd_header); }; static inline unsigned intel_engine_flag(const struct intel_engine_cs *engine) { return 1 << engine->id; } static inline void intel_flush_status_page(struct intel_engine_cs *engine, int reg) { mb(); clflush(&engine->status_page.page_addr[reg]); mb(); } static inline u32 intel_read_status_page(struct intel_engine_cs *engine, int reg) { /* Ensure that the compiler doesn't optimize away the load. */ return READ_ONCE(engine->status_page.page_addr[reg]); } static inline void intel_write_status_page(struct intel_engine_cs *engine, int reg, u32 value) { engine->status_page.page_addr[reg] = value; } /* * Reads a dword out of the status page, which is written to from the command * queue by automatic updates, MI_REPORT_HEAD, MI_STORE_DATA_INDEX, or * MI_STORE_DATA_IMM. * * The following dwords have a reserved meaning: * 0x00: ISR copy, updated when an ISR bit not set in the HWSTAM changes. * 0x04: ring 0 head pointer * 0x05: ring 1 head pointer (915-class) * 0x06: ring 2 head pointer (915-class) * 0x10-0x1b: Context status DWords (GM45) * 0x1f: Last written status offset. (GM45) * 0x20-0x2f: Reserved (Gen6+) * * The area from dword 0x30 to 0x3ff is available for driver usage. */ #define I915_GEM_HWS_INDEX 0x30 #define I915_GEM_HWS_INDEX_ADDR (I915_GEM_HWS_INDEX << MI_STORE_DWORD_INDEX_SHIFT) #define I915_GEM_HWS_SCRATCH_INDEX 0x40 #define I915_GEM_HWS_SCRATCH_ADDR (I915_GEM_HWS_SCRATCH_INDEX << MI_STORE_DWORD_INDEX_SHIFT) struct intel_ring * intel_engine_create_ring(struct intel_engine_cs *engine, int size); int intel_ring_pin(struct intel_ring *ring, unsigned int offset_bias); void intel_ring_unpin(struct intel_ring *ring); void intel_ring_free(struct intel_ring *ring); void intel_engine_stop(struct intel_engine_cs *engine); void intel_engine_cleanup(struct intel_engine_cs *engine); void intel_legacy_submission_resume(struct drm_i915_private *dev_priv); int __must_check intel_ring_begin(struct drm_i915_gem_request *req, int n); int __must_check intel_ring_cacheline_align(struct drm_i915_gem_request *req); static inline void intel_ring_emit(struct intel_ring *ring, u32 data) { *(uint32_t *)(ring->vaddr + ring->tail) = data; ring->tail += 4; } static inline void intel_ring_emit_reg(struct intel_ring *ring, i915_reg_t reg) { intel_ring_emit(ring, i915_mmio_reg_offset(reg)); } static inline void intel_ring_advance(struct intel_ring *ring) { /* Dummy function. * * This serves as a placeholder in the code so that the reader * can compare against the preceding intel_ring_begin() and * check that the number of dwords emitted matches the space * reserved for the command packet (i.e. the value passed to * intel_ring_begin()). */ } static inline u32 intel_ring_offset(struct intel_ring *ring, void *addr) { /* Don't write ring->size (equivalent to 0) as that hangs some GPUs. */ u32 offset = addr - ring->vaddr; return offset & (ring->size - 1); } int __intel_ring_space(int head, int tail, int size); void intel_ring_update_space(struct intel_ring *ring); void intel_engine_init_global_seqno(struct intel_engine_cs *engine, u32 seqno); void intel_engine_setup_common(struct intel_engine_cs *engine); int intel_engine_init_common(struct intel_engine_cs *engine); int intel_engine_create_scratch(struct intel_engine_cs *engine, int size); void intel_engine_cleanup_common(struct intel_engine_cs *engine); int intel_init_render_ring_buffer(struct intel_engine_cs *engine); int intel_init_bsd_ring_buffer(struct intel_engine_cs *engine); int intel_init_bsd2_ring_buffer(struct intel_engine_cs *engine); int intel_init_blt_ring_buffer(struct intel_engine_cs *engine); int intel_init_vebox_ring_buffer(struct intel_engine_cs *engine); u64 intel_engine_get_active_head(struct intel_engine_cs *engine); u64 intel_engine_get_last_batch_head(struct intel_engine_cs *engine); static inline u32 intel_engine_get_seqno(struct intel_engine_cs *engine) { return intel_read_status_page(engine, I915_GEM_HWS_INDEX); } static inline u32 intel_engine_last_submit(struct intel_engine_cs *engine) { /* We are only peeking at the tail of the submit queue (and not the * queue itself) in order to gain a hint as to the current active * state of the engine. Callers are not expected to be taking * engine->timeline->lock, nor are they expected to be concerned * wtih serialising this hint with anything, so document it as * a hint and nothing more. */ return READ_ONCE(engine->timeline->last_submitted_seqno); } int init_workarounds_ring(struct intel_engine_cs *engine); void intel_engine_get_instdone(struct intel_engine_cs *engine, struct intel_instdone *instdone); /* * Arbitrary size for largest possible 'add request' sequence. The code paths * are complex and variable. Empirical measurement shows that the worst case * is BDW at 192 bytes (6 + 6 + 36 dwords), then ILK at 136 bytes. However, * we need to allocate double the largest single packet within that emission * to account for tail wraparound (so 6 + 6 + 72 dwords for BDW). */ #define MIN_SPACE_FOR_ADD_REQUEST 336 static inline u32 intel_hws_seqno_address(struct intel_engine_cs *engine) { return engine->status_page.ggtt_offset + I915_GEM_HWS_INDEX_ADDR; } /* intel_breadcrumbs.c -- user interrupt bottom-half for waiters */ int intel_engine_init_breadcrumbs(struct intel_engine_cs *engine); static inline void intel_wait_init(struct intel_wait *wait, u32 seqno) { wait->tsk = current; wait->seqno = seqno; } static inline bool intel_wait_complete(const struct intel_wait *wait) { return RB_EMPTY_NODE(&wait->node); } bool intel_engine_add_wait(struct intel_engine_cs *engine, struct intel_wait *wait); void intel_engine_remove_wait(struct intel_engine_cs *engine, struct intel_wait *wait); void intel_engine_enable_signaling(struct drm_i915_gem_request *request); static inline bool intel_engine_has_waiter(const struct intel_engine_cs *engine) { return rcu_access_pointer(engine->breadcrumbs.irq_seqno_bh); } static inline bool intel_engine_wakeup(const struct intel_engine_cs *engine) { bool wakeup = false; /* Note that for this not to dangerously chase a dangling pointer, * we must hold the rcu_read_lock here. * * Also note that tsk is likely to be in !TASK_RUNNING state so an * early test for tsk->state != TASK_RUNNING before wake_up_process() * is unlikely to be beneficial. */ if (intel_engine_has_waiter(engine)) { struct task_struct *tsk; rcu_read_lock(); tsk = rcu_dereference(engine->breadcrumbs.irq_seqno_bh); if (tsk) wakeup = wake_up_process(tsk); rcu_read_unlock(); } return wakeup; } void intel_engine_reset_breadcrumbs(struct intel_engine_cs *engine); void intel_engine_fini_breadcrumbs(struct intel_engine_cs *engine); unsigned int intel_breadcrumbs_busy(struct drm_i915_private *i915); #endif /* _INTEL_RINGBUFFER_H_ */