/* * Copyright 2009 Jerome Glisse. * All Rights Reserved. * * 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, sub license, 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 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 NON-INFRINGEMENT. IN NO EVENT SHALL * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS 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. * * The above copyright notice and this permission notice (including the * next paragraph) shall be included in all copies or substantial portions * of the Software. * */ /* * Authors: * Jerome Glisse * Dave Airlie */ #include #include #include #include #include #include #include #include "amdgpu.h" #include "amdgpu_trace.h" /* * Fences * Fences mark an event in the GPUs pipeline and are used * for GPU/CPU synchronization. When the fence is written, * it is expected that all buffers associated with that fence * are no longer in use by the associated ring on the GPU and * that the the relevant GPU caches have been flushed. */ static struct kmem_cache *amdgpu_fence_slab; static atomic_t amdgpu_fence_slab_ref = ATOMIC_INIT(0); /** * amdgpu_fence_write - write a fence value * * @ring: ring the fence is associated with * @seq: sequence number to write * * Writes a fence value to memory (all asics). */ static void amdgpu_fence_write(struct amdgpu_ring *ring, u32 seq) { struct amdgpu_fence_driver *drv = &ring->fence_drv; if (drv->cpu_addr) *drv->cpu_addr = cpu_to_le32(seq); } /** * amdgpu_fence_read - read a fence value * * @ring: ring the fence is associated with * * Reads a fence value from memory (all asics). * Returns the value of the fence read from memory. */ static u32 amdgpu_fence_read(struct amdgpu_ring *ring) { struct amdgpu_fence_driver *drv = &ring->fence_drv; u32 seq = 0; if (drv->cpu_addr) seq = le32_to_cpu(*drv->cpu_addr); else seq = lower_32_bits(atomic64_read(&drv->last_seq)); return seq; } /** * amdgpu_fence_emit - emit a fence on the requested ring * * @ring: ring the fence is associated with * @owner: creator of the fence * @fence: amdgpu fence object * * Emits a fence command on the requested ring (all asics). * Returns 0 on success, -ENOMEM on failure. */ int amdgpu_fence_emit(struct amdgpu_ring *ring, void *owner, struct amdgpu_fence **fence) { struct amdgpu_device *adev = ring->adev; /* we are protected by the ring emission mutex */ *fence = kmem_cache_alloc(amdgpu_fence_slab, GFP_KERNEL); if ((*fence) == NULL) { return -ENOMEM; } (*fence)->seq = ++ring->fence_drv.sync_seq; (*fence)->ring = ring; (*fence)->owner = owner; fence_init(&(*fence)->base, &amdgpu_fence_ops, &ring->fence_drv.fence_queue.lock, adev->fence_context + ring->idx, (*fence)->seq); amdgpu_ring_emit_fence(ring, ring->fence_drv.gpu_addr, (*fence)->seq, AMDGPU_FENCE_FLAG_INT); return 0; } /** * amdgpu_fence_schedule_fallback - schedule fallback check * * @ring: pointer to struct amdgpu_ring * * Start a timer as fallback to our interrupts. */ static void amdgpu_fence_schedule_fallback(struct amdgpu_ring *ring) { mod_timer(&ring->fence_drv.fallback_timer, jiffies + AMDGPU_FENCE_JIFFIES_TIMEOUT); } /** * amdgpu_fence_activity - check for fence activity * * @ring: pointer to struct amdgpu_ring * * Checks the current fence value and calculates the last * signalled fence value. Returns true if activity occured * on the ring, and the fence_queue should be waken up. */ static bool amdgpu_fence_activity(struct amdgpu_ring *ring) { uint64_t seq, last_seq, last_emitted; unsigned count_loop = 0; bool wake = false; /* Note there is a scenario here for an infinite loop but it's * very unlikely to happen. For it to happen, the current polling * process need to be interrupted by another process and another * process needs to update the last_seq btw the atomic read and * xchg of the current process. * * More over for this to go in infinite loop there need to be * continuously new fence signaled ie amdgpu_fence_read needs * to return a different value each time for both the currently * polling process and the other process that xchg the last_seq * btw atomic read and xchg of the current process. And the * value the other process set as last seq must be higher than * the seq value we just read. Which means that current process * need to be interrupted after amdgpu_fence_read and before * atomic xchg. * * To be even more safe we count the number of time we loop and * we bail after 10 loop just accepting the fact that we might * have temporarly set the last_seq not to the true real last * seq but to an older one. */ last_seq = atomic64_read(&ring->fence_drv.last_seq); do { last_emitted = ring->fence_drv.sync_seq; seq = amdgpu_fence_read(ring); seq |= last_seq & 0xffffffff00000000LL; if (seq < last_seq) { seq &= 0xffffffff; seq |= last_emitted & 0xffffffff00000000LL; } if (seq <= last_seq || seq > last_emitted) { break; } /* If we loop over we don't want to return without * checking if a fence is signaled as it means that the * seq we just read is different from the previous on. */ wake = true; last_seq = seq; if ((count_loop++) > 10) { /* We looped over too many time leave with the * fact that we might have set an older fence * seq then the current real last seq as signaled * by the hw. */ break; } } while (atomic64_xchg(&ring->fence_drv.last_seq, seq) > seq); if (seq < last_emitted) amdgpu_fence_schedule_fallback(ring); return wake; } /** * amdgpu_fence_process - process a fence * * @adev: amdgpu_device pointer * @ring: ring index the fence is associated with * * Checks the current fence value and wakes the fence queue * if the sequence number has increased (all asics). */ void amdgpu_fence_process(struct amdgpu_ring *ring) { if (amdgpu_fence_activity(ring)) wake_up_all(&ring->fence_drv.fence_queue); } /** * amdgpu_fence_fallback - fallback for hardware interrupts * * @work: delayed work item * * Checks for fence activity. */ static void amdgpu_fence_fallback(unsigned long arg) { struct amdgpu_ring *ring = (void *)arg; amdgpu_fence_process(ring); } /** * amdgpu_fence_seq_signaled - check if a fence sequence number has signaled * * @ring: ring the fence is associated with * @seq: sequence number * * Check if the last signaled fence sequnce number is >= the requested * sequence number (all asics). * Returns true if the fence has signaled (current fence value * is >= requested value) or false if it has not (current fence * value is < the requested value. Helper function for * amdgpu_fence_signaled(). */ static bool amdgpu_fence_seq_signaled(struct amdgpu_ring *ring, u64 seq) { if (atomic64_read(&ring->fence_drv.last_seq) >= seq) return true; /* poll new last sequence at least once */ amdgpu_fence_process(ring); if (atomic64_read(&ring->fence_drv.last_seq) >= seq) return true; return false; } /* * amdgpu_ring_wait_seq_timeout - wait for seq of the specific ring to signal * @ring: ring to wait on for the seq number * @seq: seq number wait for * * return value: * 0: seq signaled, and gpu not hang * -EDEADL: GPU hang detected * -EINVAL: some paramter is not valid */ static int amdgpu_fence_ring_wait_seq(struct amdgpu_ring *ring, uint64_t seq) { bool signaled = false; BUG_ON(!ring); if (seq > ring->fence_drv.sync_seq) return -EINVAL; if (atomic64_read(&ring->fence_drv.last_seq) >= seq) return 0; amdgpu_fence_schedule_fallback(ring); wait_event(ring->fence_drv.fence_queue, ( (signaled = amdgpu_fence_seq_signaled(ring, seq)))); if (signaled) return 0; else return -EDEADLK; } /** * amdgpu_fence_wait_next - wait for the next fence to signal * * @adev: amdgpu device pointer * @ring: ring index the fence is associated with * * Wait for the next fence on the requested ring to signal (all asics). * Returns 0 if the next fence has passed, error for all other cases. * Caller must hold ring lock. */ int amdgpu_fence_wait_next(struct amdgpu_ring *ring) { uint64_t seq = atomic64_read(&ring->fence_drv.last_seq) + 1ULL; if (seq >= ring->fence_drv.sync_seq) return -ENOENT; return amdgpu_fence_ring_wait_seq(ring, seq); } /** * amdgpu_fence_wait_empty - wait for all fences to signal * * @adev: amdgpu device pointer * @ring: ring index the fence is associated with * * Wait for all fences on the requested ring to signal (all asics). * Returns 0 if the fences have passed, error for all other cases. * Caller must hold ring lock. */ int amdgpu_fence_wait_empty(struct amdgpu_ring *ring) { uint64_t seq = ring->fence_drv.sync_seq; if (!seq) return 0; return amdgpu_fence_ring_wait_seq(ring, seq); } /** * amdgpu_fence_count_emitted - get the count of emitted fences * * @ring: ring the fence is associated with * * Get the number of fences emitted on the requested ring (all asics). * Returns the number of emitted fences on the ring. Used by the * dynpm code to ring track activity. */ unsigned amdgpu_fence_count_emitted(struct amdgpu_ring *ring) { uint64_t emitted; /* We are not protected by ring lock when reading the last sequence * but it's ok to report slightly wrong fence count here. */ amdgpu_fence_process(ring); emitted = ring->fence_drv.sync_seq - atomic64_read(&ring->fence_drv.last_seq); /* to avoid 32bits warp around */ if (emitted > 0x10000000) emitted = 0x10000000; return (unsigned)emitted; } /** * amdgpu_fence_driver_start_ring - make the fence driver * ready for use on the requested ring. * * @ring: ring to start the fence driver on * @irq_src: interrupt source to use for this ring * @irq_type: interrupt type to use for this ring * * Make the fence driver ready for processing (all asics). * Not all asics have all rings, so each asic will only * start the fence driver on the rings it has. * Returns 0 for success, errors for failure. */ int amdgpu_fence_driver_start_ring(struct amdgpu_ring *ring, struct amdgpu_irq_src *irq_src, unsigned irq_type) { struct amdgpu_device *adev = ring->adev; uint64_t index; if (ring != &adev->uvd.ring) { ring->fence_drv.cpu_addr = &adev->wb.wb[ring->fence_offs]; ring->fence_drv.gpu_addr = adev->wb.gpu_addr + (ring->fence_offs * 4); } else { /* put fence directly behind firmware */ index = ALIGN(adev->uvd.fw->size, 8); ring->fence_drv.cpu_addr = adev->uvd.cpu_addr + index; ring->fence_drv.gpu_addr = adev->uvd.gpu_addr + index; } amdgpu_fence_write(ring, atomic64_read(&ring->fence_drv.last_seq)); amdgpu_irq_get(adev, irq_src, irq_type); ring->fence_drv.irq_src = irq_src; ring->fence_drv.irq_type = irq_type; ring->fence_drv.initialized = true; dev_info(adev->dev, "fence driver on ring %d use gpu addr 0x%016llx, " "cpu addr 0x%p\n", ring->idx, ring->fence_drv.gpu_addr, ring->fence_drv.cpu_addr); return 0; } /** * amdgpu_fence_driver_init_ring - init the fence driver * for the requested ring. * * @ring: ring to init the fence driver on * * Init the fence driver for the requested ring (all asics). * Helper function for amdgpu_fence_driver_init(). */ int amdgpu_fence_driver_init_ring(struct amdgpu_ring *ring) { long timeout; int r; ring->fence_drv.cpu_addr = NULL; ring->fence_drv.gpu_addr = 0; ring->fence_drv.sync_seq = 0; atomic64_set(&ring->fence_drv.last_seq, 0); ring->fence_drv.initialized = false; setup_timer(&ring->fence_drv.fallback_timer, amdgpu_fence_fallback, (unsigned long)ring); init_waitqueue_head(&ring->fence_drv.fence_queue); timeout = msecs_to_jiffies(amdgpu_lockup_timeout); if (timeout == 0) { /* * FIXME: * Delayed workqueue cannot use it directly, * so the scheduler will not use delayed workqueue if * MAX_SCHEDULE_TIMEOUT is set. * Currently keep it simple and silly. */ timeout = MAX_SCHEDULE_TIMEOUT; } r = amd_sched_init(&ring->sched, &amdgpu_sched_ops, amdgpu_sched_hw_submission, timeout, ring->name); if (r) { DRM_ERROR("Failed to create scheduler on ring %s.\n", ring->name); return r; } return 0; } /** * amdgpu_fence_driver_init - init the fence driver * for all possible rings. * * @adev: amdgpu device pointer * * Init the fence driver for all possible rings (all asics). * Not all asics have all rings, so each asic will only * start the fence driver on the rings it has using * amdgpu_fence_driver_start_ring(). * Returns 0 for success. */ int amdgpu_fence_driver_init(struct amdgpu_device *adev) { if (atomic_inc_return(&amdgpu_fence_slab_ref) == 1) { amdgpu_fence_slab = kmem_cache_create( "amdgpu_fence", sizeof(struct amdgpu_fence), 0, SLAB_HWCACHE_ALIGN, NULL); if (!amdgpu_fence_slab) return -ENOMEM; } if (amdgpu_debugfs_fence_init(adev)) dev_err(adev->dev, "fence debugfs file creation failed\n"); return 0; } /** * amdgpu_fence_driver_fini - tear down the fence driver * for all possible rings. * * @adev: amdgpu device pointer * * Tear down the fence driver for all possible rings (all asics). */ void amdgpu_fence_driver_fini(struct amdgpu_device *adev) { int i, r; if (atomic_dec_and_test(&amdgpu_fence_slab_ref)) kmem_cache_destroy(amdgpu_fence_slab); mutex_lock(&adev->ring_lock); for (i = 0; i < AMDGPU_MAX_RINGS; i++) { struct amdgpu_ring *ring = adev->rings[i]; if (!ring || !ring->fence_drv.initialized) continue; r = amdgpu_fence_wait_empty(ring); if (r) { /* no need to trigger GPU reset as we are unloading */ amdgpu_fence_driver_force_completion(adev); } wake_up_all(&ring->fence_drv.fence_queue); amdgpu_irq_put(adev, ring->fence_drv.irq_src, ring->fence_drv.irq_type); amd_sched_fini(&ring->sched); del_timer_sync(&ring->fence_drv.fallback_timer); ring->fence_drv.initialized = false; } mutex_unlock(&adev->ring_lock); } /** * amdgpu_fence_driver_suspend - suspend the fence driver * for all possible rings. * * @adev: amdgpu device pointer * * Suspend the fence driver for all possible rings (all asics). */ void amdgpu_fence_driver_suspend(struct amdgpu_device *adev) { int i, r; mutex_lock(&adev->ring_lock); for (i = 0; i < AMDGPU_MAX_RINGS; i++) { struct amdgpu_ring *ring = adev->rings[i]; if (!ring || !ring->fence_drv.initialized) continue; /* wait for gpu to finish processing current batch */ r = amdgpu_fence_wait_empty(ring); if (r) { /* delay GPU reset to resume */ amdgpu_fence_driver_force_completion(adev); } /* disable the interrupt */ amdgpu_irq_put(adev, ring->fence_drv.irq_src, ring->fence_drv.irq_type); } mutex_unlock(&adev->ring_lock); } /** * amdgpu_fence_driver_resume - resume the fence driver * for all possible rings. * * @adev: amdgpu device pointer * * Resume the fence driver for all possible rings (all asics). * Not all asics have all rings, so each asic will only * start the fence driver on the rings it has using * amdgpu_fence_driver_start_ring(). * Returns 0 for success. */ void amdgpu_fence_driver_resume(struct amdgpu_device *adev) { int i; mutex_lock(&adev->ring_lock); for (i = 0; i < AMDGPU_MAX_RINGS; i++) { struct amdgpu_ring *ring = adev->rings[i]; if (!ring || !ring->fence_drv.initialized) continue; /* enable the interrupt */ amdgpu_irq_get(adev, ring->fence_drv.irq_src, ring->fence_drv.irq_type); } mutex_unlock(&adev->ring_lock); } /** * amdgpu_fence_driver_force_completion - force all fence waiter to complete * * @adev: amdgpu device pointer * * In case of GPU reset failure make sure no process keep waiting on fence * that will never complete. */ void amdgpu_fence_driver_force_completion(struct amdgpu_device *adev) { int i; for (i = 0; i < AMDGPU_MAX_RINGS; i++) { struct amdgpu_ring *ring = adev->rings[i]; if (!ring || !ring->fence_drv.initialized) continue; amdgpu_fence_write(ring, ring->fence_drv.sync_seq); } } /* * Common fence implementation */ static const char *amdgpu_fence_get_driver_name(struct fence *fence) { return "amdgpu"; } static const char *amdgpu_fence_get_timeline_name(struct fence *f) { struct amdgpu_fence *fence = to_amdgpu_fence(f); return (const char *)fence->ring->name; } /** * amdgpu_fence_is_signaled - test if fence is signaled * * @f: fence to test * * Test the fence sequence number if it is already signaled. If it isn't * signaled start fence processing. Returns True if the fence is signaled. */ static bool amdgpu_fence_is_signaled(struct fence *f) { struct amdgpu_fence *fence = to_amdgpu_fence(f); struct amdgpu_ring *ring = fence->ring; if (atomic64_read(&ring->fence_drv.last_seq) >= fence->seq) return true; amdgpu_fence_process(ring); if (atomic64_read(&ring->fence_drv.last_seq) >= fence->seq) return true; return false; } /** * amdgpu_fence_check_signaled - callback from fence_queue * * this function is called with fence_queue lock held, which is also used * for the fence locking itself, so unlocked variants are used for * fence_signal, and remove_wait_queue. */ static int amdgpu_fence_check_signaled(wait_queue_t *wait, unsigned mode, int flags, void *key) { struct amdgpu_fence *fence; struct amdgpu_device *adev; u64 seq; int ret; fence = container_of(wait, struct amdgpu_fence, fence_wake); adev = fence->ring->adev; /* * We cannot use amdgpu_fence_process here because we're already * in the waitqueue, in a call from wake_up_all. */ seq = atomic64_read(&fence->ring->fence_drv.last_seq); if (seq >= fence->seq) { ret = fence_signal_locked(&fence->base); if (!ret) FENCE_TRACE(&fence->base, "signaled from irq context\n"); else FENCE_TRACE(&fence->base, "was already signaled\n"); __remove_wait_queue(&fence->ring->fence_drv.fence_queue, &fence->fence_wake); fence_put(&fence->base); } else FENCE_TRACE(&fence->base, "pending\n"); return 0; } /** * amdgpu_fence_enable_signaling - enable signalling on fence * @fence: fence * * This function is called with fence_queue lock held, and adds a callback * to fence_queue that checks if this fence is signaled, and if so it * signals the fence and removes itself. */ static bool amdgpu_fence_enable_signaling(struct fence *f) { struct amdgpu_fence *fence = to_amdgpu_fence(f); struct amdgpu_ring *ring = fence->ring; if (atomic64_read(&ring->fence_drv.last_seq) >= fence->seq) return false; fence->fence_wake.flags = 0; fence->fence_wake.private = NULL; fence->fence_wake.func = amdgpu_fence_check_signaled; __add_wait_queue(&ring->fence_drv.fence_queue, &fence->fence_wake); fence_get(f); if (!timer_pending(&ring->fence_drv.fallback_timer)) amdgpu_fence_schedule_fallback(ring); FENCE_TRACE(&fence->base, "armed on ring %i!\n", ring->idx); return true; } static void amdgpu_fence_release(struct fence *f) { struct amdgpu_fence *fence = to_amdgpu_fence(f); kmem_cache_free(amdgpu_fence_slab, fence); } const struct fence_ops amdgpu_fence_ops = { .get_driver_name = amdgpu_fence_get_driver_name, .get_timeline_name = amdgpu_fence_get_timeline_name, .enable_signaling = amdgpu_fence_enable_signaling, .signaled = amdgpu_fence_is_signaled, .wait = fence_default_wait, .release = amdgpu_fence_release, }; /* * Fence debugfs */ #if defined(CONFIG_DEBUG_FS) static int amdgpu_debugfs_fence_info(struct seq_file *m, void *data) { struct drm_info_node *node = (struct drm_info_node *)m->private; struct drm_device *dev = node->minor->dev; struct amdgpu_device *adev = dev->dev_private; int i; for (i = 0; i < AMDGPU_MAX_RINGS; ++i) { struct amdgpu_ring *ring = adev->rings[i]; if (!ring || !ring->fence_drv.initialized) continue; amdgpu_fence_process(ring); seq_printf(m, "--- ring %d (%s) ---\n", i, ring->name); seq_printf(m, "Last signaled fence 0x%016llx\n", (unsigned long long)atomic64_read(&ring->fence_drv.last_seq)); seq_printf(m, "Last emitted 0x%016llx\n", ring->fence_drv.sync_seq); } return 0; } static struct drm_info_list amdgpu_debugfs_fence_list[] = { {"amdgpu_fence_info", &amdgpu_debugfs_fence_info, 0, NULL}, }; #endif int amdgpu_debugfs_fence_init(struct amdgpu_device *adev) { #if defined(CONFIG_DEBUG_FS) return amdgpu_debugfs_add_files(adev, amdgpu_debugfs_fence_list, 1); #else return 0; #endif }