drivers/gpu/drm/amd/amdgpu/amdgpu_ih.c

   1 /*
   2  * Copyright 2014 Advanced Micro Devices, Inc.
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice shall be included in
  12  * all copies or substantial portions of the Software.
  13  *
  14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
  18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  20  * OTHER DEALINGS IN THE SOFTWARE.
  21  *
  22  */
  23
  24 #include <drm/drmP.h>
  25 #include "amdgpu.h"
  26 #include "amdgpu_ih.h"
  27 #include "amdgpu_amdkfd.h"
  28
  29 /**
  30  * amdgpu_ih_ring_alloc - allocate memory for the IH ring
  31  *
  32  * @adev: amdgpu_device pointer
  33  *
  34  * Allocate a ring buffer for the interrupt controller.
  35  * Returns 0 for success, errors for failure.
  36  */
  37 static int amdgpu_ih_ring_alloc(struct amdgpu_device *adev)
  38 {
  39         int r;
  40
  41         /* Allocate ring buffer */
  42         if (adev->irq.ih.ring_obj == NULL) {
  43                 r = amdgpu_bo_create_kernel(adev, adev->irq.ih.ring_size,
  44                                             PAGE_SIZE, AMDGPU_GEM_DOMAIN_GTT,
  45                                             &adev->irq.ih.ring_obj,
  46                                             &adev->irq.ih.gpu_addr,
  47                                             (void **)&adev->irq.ih.ring);
  48                 if (r) {
  49                         DRM_ERROR("amdgpu: failed to create ih ring buffer (%d).\n", r);
  50                         return r;
  51                 }
  52         }
  53         return 0;
  54 }
  55
  56 /**
  57  * amdgpu_ih_ring_init - initialize the IH state
  58  *
  59  * @adev: amdgpu_device pointer
  60  *
  61  * Initializes the IH state and allocates a buffer
  62  * for the IH ring buffer.
  63  * Returns 0 for success, errors for failure.
  64  */
  65 int amdgpu_ih_ring_init(struct amdgpu_device *adev, unsigned ring_size,
  66                         bool use_bus_addr)
  67 {
  68         u32 rb_bufsz;
  69         int r;
  70
  71         /* Align ring size */
  72         rb_bufsz = order_base_2(ring_size / 4);
  73         ring_size = (1 << rb_bufsz) * 4;
  74         adev->irq.ih.ring_size = ring_size;
  75         adev->irq.ih.ptr_mask = adev->irq.ih.ring_size - 1;
  76         adev->irq.ih.rptr = 0;
  77         adev->irq.ih.use_bus_addr = use_bus_addr;
  78
  79         if (adev->irq.ih.use_bus_addr) {
  80                 if (!adev->irq.ih.ring) {
  81                         /* add 8 bytes for the rptr/wptr shadows and
  82                          * add them to the end of the ring allocation.
  83                          */
  84                         adev->irq.ih.ring = pci_alloc_consistent(adev->pdev,
  85                                                                  adev->irq.ih.ring_size + 8,
  86                                                                  &adev->irq.ih.rb_dma_addr);
  87                         if (adev->irq.ih.ring == NULL)
  88                                 return -ENOMEM;
  89                         memset((void *)adev->irq.ih.ring, 0, adev->irq.ih.ring_size + 8);
  90                         adev->irq.ih.wptr_offs = (adev->irq.ih.ring_size / 4) + 0;
  91                         adev->irq.ih.rptr_offs = (adev->irq.ih.ring_size / 4) + 1;
  92                 }
  93                 return 0;
  94         } else {
  95                 r = amdgpu_wb_get(adev, &adev->irq.ih.wptr_offs);
  96                 if (r) {
  97                         dev_err(adev->dev, "(%d) ih wptr_offs wb alloc failed\n", r);
  98                         return r;
  99                 }
 100
 101                 r = amdgpu_wb_get(adev, &adev->irq.ih.rptr_offs);
 102                 if (r) {
 103                         amdgpu_wb_free(adev, adev->irq.ih.wptr_offs);
 104                         dev_err(adev->dev, "(%d) ih rptr_offs wb alloc failed\n", r);
 105                         return r;
 106                 }
 107
 108                 return amdgpu_ih_ring_alloc(adev);
 109         }
 110 }
 111
 112 /**
 113  * amdgpu_ih_ring_fini - tear down the IH state
 114  *
 115  * @adev: amdgpu_device pointer
 116  *
 117  * Tears down the IH state and frees buffer
 118  * used for the IH ring buffer.
 119  */
 120 void amdgpu_ih_ring_fini(struct amdgpu_device *adev)
 121 {
 122         int r;
 123
 124         if (adev->irq.ih.use_bus_addr) {
 125                 if (adev->irq.ih.ring) {
 126                         /* add 8 bytes for the rptr/wptr shadows and
 127                          * add them to the end of the ring allocation.
 128                          */
 129                         pci_free_consistent(adev->pdev, adev->irq.ih.ring_size + 8,
 130                                             (void *)adev->irq.ih.ring,
 131                                             adev->irq.ih.rb_dma_addr);
 132                         adev->irq.ih.ring = NULL;
 133                 }
 134         } else {
 135                 if (adev->irq.ih.ring_obj) {
 136                         r = amdgpu_bo_reserve(adev->irq.ih.ring_obj, false);
 137                         if (likely(r == 0)) {
 138                                 amdgpu_bo_kunmap(adev->irq.ih.ring_obj);
 139                                 amdgpu_bo_unpin(adev->irq.ih.ring_obj);
 140                                 amdgpu_bo_unreserve(adev->irq.ih.ring_obj);
 141                         }
 142                         amdgpu_bo_unref(&adev->irq.ih.ring_obj);
 143                         adev->irq.ih.ring = NULL;
 144                         adev->irq.ih.ring_obj = NULL;
 145                 }
 146                 amdgpu_wb_free(adev, adev->irq.ih.wptr_offs);
 147                 amdgpu_wb_free(adev, adev->irq.ih.rptr_offs);
 148         }
 149 }
 150
 151 /**
 152  * amdgpu_ih_process - interrupt handler
 153  *
 154  * @adev: amdgpu_device pointer
 155  *
 156  * Interrupt hander (VI), walk the IH ring.
 157  * Returns irq process return code.
 158  */
 159 int amdgpu_ih_process(struct amdgpu_device *adev)
 160 {
 161         struct amdgpu_iv_entry entry;
 162         u32 wptr;
 163
 164         if (!adev->irq.ih.enabled || adev->shutdown)
 165                 return IRQ_NONE;
 166
 167         wptr = amdgpu_ih_get_wptr(adev);
 168
 169 restart_ih:
 170         /* is somebody else already processing irqs? */
 171         if (atomic_xchg(&adev->irq.ih.lock, 1))
 172                 return IRQ_NONE;
 173
 174         DRM_DEBUG("%s: rptr %d, wptr %d\n", __func__, adev->irq.ih.rptr, wptr);
 175
 176         /* Order reading of wptr vs. reading of IH ring data */
 177         rmb();
 178
 179         while (adev->irq.ih.rptr != wptr) {
 180                 u32 ring_index = adev->irq.ih.rptr >> 2;
 181
 182                 /* Before dispatching irq to IP blocks, send it to amdkfd */
 183                 amdgpu_amdkfd_interrupt(adev,
 184                                 (const void *) &adev->irq.ih.ring[ring_index]);
 185
 186                 entry.iv_entry = (const uint32_t *)
 187                         &adev->irq.ih.ring[ring_index];
 188                 amdgpu_ih_decode_iv(adev, &entry);
 189                 adev->irq.ih.rptr &= adev->irq.ih.ptr_mask;
 190
 191                 amdgpu_irq_dispatch(adev, &entry);
 192         }
 193         amdgpu_ih_set_rptr(adev);
 194         atomic_set(&adev->irq.ih.lock, 0);
 195
 196         /* make sure wptr hasn't changed while processing */
 197         wptr = amdgpu_ih_get_wptr(adev);
 198         if (wptr != adev->irq.ih.rptr)
 199                 goto restart_ih;
 200
 201         return IRQ_HANDLED;
 202 }