1 files changed, 274 insertions, 0 deletions
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ih.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ih.c
new file mode 100644
index 000000000..06373d44b
--- /dev/null
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ih.c
@@ -0,0 +1,274 @@
+/*
+ * 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.
+ *
+ */
+
+#include <drm/drmP.h>
+#include "amdgpu.h"
+#include "amdgpu_ih.h"
+#include "amdgpu_amdkfd.h"
+
+/**
+ * amdgpu_ih_ring_alloc - allocate memory for the IH ring
+ *
+ * @adev: amdgpu_device pointer
+ *
+ * Allocate a ring buffer for the interrupt controller.
+ * Returns 0 for success, errors for failure.
+ */
+static int amdgpu_ih_ring_alloc(struct amdgpu_device *adev)
+{
+	int r;
+
+	/* Allocate ring buffer */
+	if (adev->irq.ih.ring_obj == NULL) {
+		r = amdgpu_bo_create_kernel(adev, adev->irq.ih.ring_size,
+					    PAGE_SIZE, AMDGPU_GEM_DOMAIN_GTT,
+					    &adev->irq.ih.ring_obj,
+					    &adev->irq.ih.gpu_addr,
+					    (void **)&adev->irq.ih.ring);
+		if (r) {
+			DRM_ERROR("amdgpu: failed to create ih ring buffer (%d).\n", r);
+			return r;
+		}
+	}
+	return 0;
+}
+
+/**
+ * amdgpu_ih_ring_init - initialize the IH state
+ *
+ * @adev: amdgpu_device pointer
+ *
+ * Initializes the IH state and allocates a buffer
+ * for the IH ring buffer.
+ * Returns 0 for success, errors for failure.
+ */
+int amdgpu_ih_ring_init(struct amdgpu_device *adev, unsigned ring_size,
+			bool use_bus_addr)
+{
+	u32 rb_bufsz;
+	int r;
+
+	/* Align ring size */
+	rb_bufsz = order_base_2(ring_size / 4);
+	ring_size = (1 << rb_bufsz) * 4;
+	adev->irq.ih.ring_size = ring_size;
+	adev->irq.ih.ptr_mask = adev->irq.ih.ring_size - 1;
+	adev->irq.ih.rptr = 0;
+	adev->irq.ih.use_bus_addr = use_bus_addr;
+
+	if (adev->irq.ih.use_bus_addr) {
+		if (!adev->irq.ih.ring) {
+			/* add 8 bytes for the rptr/wptr shadows and
+			 * add them to the end of the ring allocation.
+			 */
+			adev->irq.ih.ring = pci_alloc_consistent(adev->pdev,
+								 adev->irq.ih.ring_size + 8,
+								 &adev->irq.ih.rb_dma_addr);
+			if (adev->irq.ih.ring == NULL)
+				return -ENOMEM;
+			memset((void *)adev->irq.ih.ring, 0, adev->irq.ih.ring_size + 8);
+			adev->irq.ih.wptr_offs = (adev->irq.ih.ring_size / 4) + 0;
+			adev->irq.ih.rptr_offs = (adev->irq.ih.ring_size / 4) + 1;
+		}
+		return 0;
+	} else {
+		r = amdgpu_device_wb_get(adev, &adev->irq.ih.wptr_offs);
+		if (r) {
+			dev_err(adev->dev, "(%d) ih wptr_offs wb alloc failed\n", r);
+			return r;
+		}
+
+		r = amdgpu_device_wb_get(adev, &adev->irq.ih.rptr_offs);
+		if (r) {
+			amdgpu_device_wb_free(adev, adev->irq.ih.wptr_offs);
+			dev_err(adev->dev, "(%d) ih rptr_offs wb alloc failed\n", r);
+			return r;
+		}
+
+		return amdgpu_ih_ring_alloc(adev);
+	}
+}
+
+/**
+ * amdgpu_ih_ring_fini - tear down the IH state
+ *
+ * @adev: amdgpu_device pointer
+ *
+ * Tears down the IH state and frees buffer
+ * used for the IH ring buffer.
+ */
+void amdgpu_ih_ring_fini(struct amdgpu_device *adev)
+{
+	if (adev->irq.ih.use_bus_addr) {
+		if (adev->irq.ih.ring) {
+			/* add 8 bytes for the rptr/wptr shadows and
+			 * add them to the end of the ring allocation.
+			 */
+			pci_free_consistent(adev->pdev, adev->irq.ih.ring_size + 8,
+					    (void *)adev->irq.ih.ring,
+					    adev->irq.ih.rb_dma_addr);
+			adev->irq.ih.ring = NULL;
+		}
+	} else {
+		amdgpu_bo_free_kernel(&adev->irq.ih.ring_obj,
+				      &adev->irq.ih.gpu_addr,
+				      (void **)&adev->irq.ih.ring);
+		amdgpu_device_wb_free(adev, adev->irq.ih.wptr_offs);
+		amdgpu_device_wb_free(adev, adev->irq.ih.rptr_offs);
+	}
+}
+
+/**
+ * amdgpu_ih_process - interrupt handler
+ *
+ * @adev: amdgpu_device pointer
+ *
+ * Interrupt hander (VI), walk the IH ring.
+ * Returns irq process return code.
+ */
+int amdgpu_ih_process(struct amdgpu_device *adev)
+{
+	struct amdgpu_iv_entry entry;
+	u32 wptr;
+
+	if (!adev->irq.ih.enabled || adev->shutdown)
+		return IRQ_NONE;
+
+	wptr = amdgpu_ih_get_wptr(adev);
+
+restart_ih:
+	/* is somebody else already processing irqs? */
+	if (atomic_xchg(&adev->irq.ih.lock, 1))
+		return IRQ_NONE;
+
+	DRM_DEBUG("%s: rptr %d, wptr %d\n", __func__, adev->irq.ih.rptr, wptr);
+
+	/* Order reading of wptr vs. reading of IH ring data */
+	rmb();
+
+	while (adev->irq.ih.rptr != wptr) {
+		u32 ring_index = adev->irq.ih.rptr >> 2;
+
+		/* Prescreening of high-frequency interrupts */
+		if (!amdgpu_ih_prescreen_iv(adev)) {
+			adev->irq.ih.rptr &= adev->irq.ih.ptr_mask;
+			continue;
+		}
+
+		/* Before dispatching irq to IP blocks, send it to amdkfd */
+		amdgpu_amdkfd_interrupt(adev,
+				(const void *) &adev->irq.ih.ring[ring_index]);
+
+		entry.iv_entry = (const uint32_t *)
+			&adev->irq.ih.ring[ring_index];
+		amdgpu_ih_decode_iv(adev, &entry);
+		adev->irq.ih.rptr &= adev->irq.ih.ptr_mask;
+
+		amdgpu_irq_dispatch(adev, &entry);
+	}
+	amdgpu_ih_set_rptr(adev);
+	atomic_set(&adev->irq.ih.lock, 0);
+
+	/* make sure wptr hasn't changed while processing */
+	wptr = amdgpu_ih_get_wptr(adev);
+	if (wptr != adev->irq.ih.rptr)
+		goto restart_ih;
+
+	return IRQ_HANDLED;
+}
+
+/**
+ * amdgpu_ih_add_fault - Add a page fault record
+ *
+ * @adev: amdgpu device pointer
+ * @key: 64-bit encoding of PASID and address
+ *
+ * This should be called when a retry page fault interrupt is
+ * received. If this is a new page fault, it will be added to a hash
+ * table. The return value indicates whether this is a new fault, or
+ * a fault that was already known and is already being handled.
+ *
+ * If there are too many pending page faults, this will fail. Retry
+ * interrupts should be ignored in this case until there is enough
+ * free space.
+ *
+ * Returns 0 if the fault was added, 1 if the fault was already known,
+ * -ENOSPC if there are too many pending faults.
+ */
+int amdgpu_ih_add_fault(struct amdgpu_device *adev, u64 key)
+{
+	unsigned long flags;
+	int r = -ENOSPC;
+
+	if (WARN_ON_ONCE(!adev->irq.ih.faults))
+		/* Should be allocated in <IP>_ih_sw_init on GPUs that
+		 * support retry faults and require retry filtering.
+		 */
+		return r;
+
+	spin_lock_irqsave(&adev->irq.ih.faults->lock, flags);
+
+	/* Only let the hash table fill up to 50% for best performance */
+	if (adev->irq.ih.faults->count >= (1 << (AMDGPU_PAGEFAULT_HASH_BITS-1)))
+		goto unlock_out;
+
+	r = chash_table_copy_in(&adev->irq.ih.faults->hash, key, NULL);
+	if (!r)
+		adev->irq.ih.faults->count++;
+
+	/* chash_table_copy_in should never fail unless we're losing count */
+	WARN_ON_ONCE(r < 0);
+
+unlock_out:
+	spin_unlock_irqrestore(&adev->irq.ih.faults->lock, flags);
+	return r;
+}
+
+/**
+ * amdgpu_ih_clear_fault - Remove a page fault record
+ *
+ * @adev: amdgpu device pointer
+ * @key: 64-bit encoding of PASID and address
+ *
+ * This should be called when a page fault has been handled. Any
+ * future interrupt with this key will be processed as a new
+ * page fault.
+ */
+void amdgpu_ih_clear_fault(struct amdgpu_device *adev, u64 key)
+{
+	unsigned long flags;
+	int r;
+
+	if (!adev->irq.ih.faults)
+		return;
+
+	spin_lock_irqsave(&adev->irq.ih.faults->lock, flags);
+
+	r = chash_table_remove(&adev->irq.ih.faults->hash, key, NULL);
+	if (!WARN_ON_ONCE(r < 0)) {
+		adev->irq.ih.faults->count--;
+		WARN_ON_ONCE(adev->irq.ih.faults->count < 0);
+	}
+
+	spin_unlock_irqrestore(&adev->irq.ih.faults->lock, flags);
+}