/*
* 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"
/**
* 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(adev, adev->irq.ih.ring_size,
PAGE_SIZE, true,
AMDGPU_GEM_DOMAIN_GTT, 0,
NULL, &adev->irq.ih.ring_obj);
if (r) {
DRM_ERROR("amdgpu: failed to create ih ring buffer (%d).\n", r);
return r;
}
r = amdgpu_bo_reserve(adev->irq.ih.ring_obj, false);
if (unlikely(r != 0))
return r;
r = amdgpu_bo_pin(adev->irq.ih.ring_obj,
AMDGPU_GEM_DOMAIN_GTT,
&adev->irq.ih.gpu_addr);
if (r) {
amdgpu_bo_unreserve(adev->irq.ih.ring_obj);
DRM_ERROR("amdgpu: failed to pin ih ring buffer (%d).\n", r);
return r;
}
r = amdgpu_bo_kmap(adev->irq.ih.ring_obj,
(void **)&adev->irq.ih.ring);
amdgpu_bo_unreserve(adev->irq.ih.ring_obj);
if (r) {
DRM_ERROR("amdgpu: failed to map 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 = kzalloc(adev->irq.ih.ring_size + 8, GFP_KERNEL);
if (adev->irq.ih.ring == NULL)
return -ENOMEM;
adev->irq.ih.rb_dma_addr = pci_map_single(adev->pdev,
(void *)adev->irq.ih.ring,
adev->irq.ih.ring_size,
PCI_DMA_BIDIRECTIONAL);
if (pci_dma_mapping_error(adev->pdev, adev->irq.ih.rb_dma_addr)) {
dev_err(&adev->pdev->dev, "Failed to DMA MAP the IH RB page\n");
kfree((void *)adev->irq.ih.ring);
return -ENOMEM;
}
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_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_wb_get(adev, &adev->irq.ih.rptr_offs);
if (r) {
amdgpu_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)
{
int r;
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_unmap_single(adev->pdev, adev->irq.ih.rb_dma_addr,
adev->irq.ih.ring_size + 8, PCI_DMA_BIDIRECTIONAL);
kfree((void *)adev->irq.ih.ring);
adev->irq.ih.ring = NULL;
}
} else {
if (adev->irq.ih.ring_obj) {
r = amdgpu_bo_reserve(adev->irq.ih.ring_obj, false);
if (likely(r == 0)) {
amdgpu_bo_kunmap(adev->irq.ih.ring_obj);
amdgpu_bo_unpin(adev->irq.ih.ring_obj);
amdgpu_bo_unreserve(adev->irq.ih.ring_obj);
}
amdgpu_bo_unref(&adev->irq.ih.ring_obj);
adev->irq.ih.ring = NULL;
adev->irq.ih.ring_obj = NULL;
}
amdgpu_wb_free(adev, adev->irq.ih.wptr_offs);
amdgpu_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) {
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;
}