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path: root/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
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Diffstat (limited to 'drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c')
-rw-r--r--drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c176
1 files changed, 0 insertions, 176 deletions
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c b/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
deleted file mode 100644
index 5b999095a1f7..000000000000
--- a/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
+++ /dev/null
@@ -1,176 +0,0 @@
-/*
- * Copyright 2014 Advanced Micro Devices, Inc.
- *
- * 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 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 COPYRIGHT HOLDER(S) OR AUTHOR(S) 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.
- */
-
-/*
- * KFD Interrupts.
- *
- * AMD GPUs deliver interrupts by pushing an interrupt description onto the
- * interrupt ring and then sending an interrupt. KGD receives the interrupt
- * in ISR and sends us a pointer to each new entry on the interrupt ring.
- *
- * We generally can't process interrupt-signaled events from ISR, so we call
- * out to each interrupt client module (currently only the scheduler) to ask if
- * each interrupt is interesting. If they return true, then it requires further
- * processing so we copy it to an internal interrupt ring and call each
- * interrupt client again from a work-queue.
- *
- * There's no acknowledgment for the interrupts we use. The hardware simply
- * queues a new interrupt each time without waiting.
- *
- * The fixed-size internal queue means that it's possible for us to lose
- * interrupts because we have no back-pressure to the hardware.
- */
-
-#include <linux/slab.h>
-#include <linux/device.h>
-#include "kfd_priv.h"
-
-#define KFD_INTERRUPT_RING_SIZE 256
-
-static void interrupt_wq(struct work_struct *);
-
-int kfd_interrupt_init(struct kfd_dev *kfd)
-{
- void *interrupt_ring = kmalloc_array(KFD_INTERRUPT_RING_SIZE,
- kfd->device_info->ih_ring_entry_size,
- GFP_KERNEL);
- if (!interrupt_ring)
- return -ENOMEM;
-
- kfd->interrupt_ring = interrupt_ring;
- kfd->interrupt_ring_size =
- KFD_INTERRUPT_RING_SIZE * kfd->device_info->ih_ring_entry_size;
- atomic_set(&kfd->interrupt_ring_wptr, 0);
- atomic_set(&kfd->interrupt_ring_rptr, 0);
-
- spin_lock_init(&kfd->interrupt_lock);
-
- INIT_WORK(&kfd->interrupt_work, interrupt_wq);
-
- kfd->interrupts_active = true;
-
- /*
- * After this function returns, the interrupt will be enabled. This
- * barrier ensures that the interrupt running on a different processor
- * sees all the above writes.
- */
- smp_wmb();
-
- return 0;
-}
-
-void kfd_interrupt_exit(struct kfd_dev *kfd)
-{
- /*
- * Stop the interrupt handler from writing to the ring and scheduling
- * workqueue items. The spinlock ensures that any interrupt running
- * after we have unlocked sees interrupts_active = false.
- */
- unsigned long flags;
-
- spin_lock_irqsave(&kfd->interrupt_lock, flags);
- kfd->interrupts_active = false;
- spin_unlock_irqrestore(&kfd->interrupt_lock, flags);
-
- /*
- * Flush_scheduled_work ensures that there are no outstanding
- * work-queue items that will access interrupt_ring. New work items
- * can't be created because we stopped interrupt handling above.
- */
- flush_scheduled_work();
-
- kfree(kfd->interrupt_ring);
-}
-
-/*
- * This assumes that it can't be called concurrently with itself
- * but only with dequeue_ih_ring_entry.
- */
-bool enqueue_ih_ring_entry(struct kfd_dev *kfd, const void *ih_ring_entry)
-{
- unsigned int rptr = atomic_read(&kfd->interrupt_ring_rptr);
- unsigned int wptr = atomic_read(&kfd->interrupt_ring_wptr);
-
- if ((rptr - wptr) % kfd->interrupt_ring_size ==
- kfd->device_info->ih_ring_entry_size) {
- /* This is very bad, the system is likely to hang. */
- dev_err_ratelimited(kfd_chardev(),
- "Interrupt ring overflow, dropping interrupt.\n");
- return false;
- }
-
- memcpy(kfd->interrupt_ring + wptr, ih_ring_entry,
- kfd->device_info->ih_ring_entry_size);
-
- wptr = (wptr + kfd->device_info->ih_ring_entry_size) %
- kfd->interrupt_ring_size;
- smp_wmb(); /* Ensure memcpy'd data is visible before wptr update. */
- atomic_set(&kfd->interrupt_ring_wptr, wptr);
-
- return true;
-}
-
-/*
- * This assumes that it can't be called concurrently with itself
- * but only with enqueue_ih_ring_entry.
- */
-static bool dequeue_ih_ring_entry(struct kfd_dev *kfd, void *ih_ring_entry)
-{
- /*
- * Assume that wait queues have an implicit barrier, i.e. anything that
- * happened in the ISR before it queued work is visible.
- */
-
- unsigned int wptr = atomic_read(&kfd->interrupt_ring_wptr);
- unsigned int rptr = atomic_read(&kfd->interrupt_ring_rptr);
-
- if (rptr == wptr)
- return false;
-
- memcpy(ih_ring_entry, kfd->interrupt_ring + rptr,
- kfd->device_info->ih_ring_entry_size);
-
- rptr = (rptr + kfd->device_info->ih_ring_entry_size) %
- kfd->interrupt_ring_size;
-
- /*
- * Ensure the rptr write update is not visible until
- * memcpy has finished reading.
- */
- smp_mb();
- atomic_set(&kfd->interrupt_ring_rptr, rptr);
-
- return true;
-}
-
-static void interrupt_wq(struct work_struct *work)
-{
- struct kfd_dev *dev = container_of(work, struct kfd_dev,
- interrupt_work);
-
- uint32_t ih_ring_entry[DIV_ROUND_UP(
- dev->device_info->ih_ring_entry_size,
- sizeof(uint32_t))];
-
- while (dequeue_ih_ring_entry(dev, ih_ring_entry))
- ;
-}