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 (u64 *)&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_device_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_device_wb_get(adev, &adev->irq.ih.rptr_offs); 102 if (r) { 103 amdgpu_device_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 if (adev->irq.ih.use_bus_addr) { 123 if (adev->irq.ih.ring) { 124 /* add 8 bytes for the rptr/wptr shadows and 125 * add them to the end of the ring allocation. 126 */ 127 pci_free_consistent(adev->pdev, adev->irq.ih.ring_size + 8, 128 (void *)adev->irq.ih.ring, 129 adev->irq.ih.rb_dma_addr); 130 adev->irq.ih.ring = NULL; 131 } 132 } else { 133 amdgpu_bo_free_kernel(&adev->irq.ih.ring_obj, 134 (u64 *)&adev->irq.ih.gpu_addr, 135 (void **)&adev->irq.ih.ring); 136 amdgpu_device_wb_free(adev, adev->irq.ih.wptr_offs); 137 amdgpu_device_wb_free(adev, adev->irq.ih.rptr_offs); 138 } 139 } 140 141 /** 142 * amdgpu_ih_process - interrupt handler 143 * 144 * @adev: amdgpu_device pointer 145 * 146 * Interrupt hander (VI), walk the IH ring. 147 * Returns irq process return code. 148 */ 149 int amdgpu_ih_process(struct amdgpu_device *adev) 150 { 151 struct amdgpu_iv_entry entry; 152 u32 wptr; 153 154 if (!adev->irq.ih.enabled || adev->shutdown) 155 return IRQ_NONE; 156 157 wptr = amdgpu_ih_get_wptr(adev); 158 159 restart_ih: 160 /* is somebody else already processing irqs? */ 161 if (atomic_xchg(&adev->irq.ih.lock, 1)) 162 return IRQ_NONE; 163 164 DRM_DEBUG("%s: rptr %d, wptr %d\n", __func__, adev->irq.ih.rptr, wptr); 165 166 /* Order reading of wptr vs. reading of IH ring data */ 167 rmb(); 168 169 while (adev->irq.ih.rptr != wptr) { 170 u32 ring_index = adev->irq.ih.rptr >> 2; 171 172 /* Prescreening of high-frequency interrupts */ 173 if (!amdgpu_ih_prescreen_iv(adev)) { 174 adev->irq.ih.rptr &= adev->irq.ih.ptr_mask; 175 continue; 176 } 177 178 /* Before dispatching irq to IP blocks, send it to amdkfd */ 179 amdgpu_amdkfd_interrupt(adev, 180 (const void *) &adev->irq.ih.ring[ring_index]); 181 182 entry.iv_entry = (const uint32_t *) 183 &adev->irq.ih.ring[ring_index]; 184 amdgpu_ih_decode_iv(adev, &entry); 185 adev->irq.ih.rptr &= adev->irq.ih.ptr_mask; 186 187 amdgpu_irq_dispatch(adev, &entry); 188 } 189 amdgpu_ih_set_rptr(adev); 190 atomic_set(&adev->irq.ih.lock, 0); 191 192 /* make sure wptr hasn't changed while processing */ 193 wptr = amdgpu_ih_get_wptr(adev); 194 if (wptr != adev->irq.ih.rptr) 195 goto restart_ih; 196 197 return IRQ_HANDLED; 198 } 199 200 /** 201 * amdgpu_ih_add_fault - Add a page fault record 202 * 203 * @adev: amdgpu device pointer 204 * @key: 64-bit encoding of PASID and address 205 * 206 * This should be called when a retry page fault interrupt is 207 * received. If this is a new page fault, it will be added to a hash 208 * table. The return value indicates whether this is a new fault, or 209 * a fault that was already known and is already being handled. 210 * 211 * If there are too many pending page faults, this will fail. Retry 212 * interrupts should be ignored in this case until there is enough 213 * free space. 214 * 215 * Returns 0 if the fault was added, 1 if the fault was already known, 216 * -ENOSPC if there are too many pending faults. 217 */ 218 int amdgpu_ih_add_fault(struct amdgpu_device *adev, u64 key) 219 { 220 unsigned long flags; 221 int r = -ENOSPC; 222 223 if (WARN_ON_ONCE(!adev->irq.ih.faults)) 224 /* Should be allocated in <IP>_ih_sw_init on GPUs that 225 * support retry faults and require retry filtering. 226 */ 227 return r; 228 229 spin_lock_irqsave(&adev->irq.ih.faults->lock, flags); 230 231 /* Only let the hash table fill up to 50% for best performance */ 232 if (adev->irq.ih.faults->count >= (1 << (AMDGPU_PAGEFAULT_HASH_BITS-1))) 233 goto unlock_out; 234 235 r = chash_table_copy_in(&adev->irq.ih.faults->hash, key, NULL); 236 if (!r) 237 adev->irq.ih.faults->count++; 238 239 /* chash_table_copy_in should never fail unless we're losing count */ 240 WARN_ON_ONCE(r < 0); 241 242 unlock_out: 243 spin_unlock_irqrestore(&adev->irq.ih.faults->lock, flags); 244 return r; 245 } 246 247 /** 248 * amdgpu_ih_clear_fault - Remove a page fault record 249 * 250 * @adev: amdgpu device pointer 251 * @key: 64-bit encoding of PASID and address 252 * 253 * This should be called when a page fault has been handled. Any 254 * future interrupt with this key will be processed as a new 255 * page fault. 256 */ 257 void amdgpu_ih_clear_fault(struct amdgpu_device *adev, u64 key) 258 { 259 unsigned long flags; 260 int r; 261 262 if (!adev->irq.ih.faults) 263 return; 264 265 spin_lock_irqsave(&adev->irq.ih.faults->lock, flags); 266 267 r = chash_table_remove(&adev->irq.ih.faults->hash, key, NULL); 268 if (!WARN_ON_ONCE(r < 0)) { 269 adev->irq.ih.faults->count--; 270 WARN_ON_ONCE(adev->irq.ih.faults->count < 0); 271 } 272 273 spin_unlock_irqrestore(&adev->irq.ih.faults->lock, flags); 274 } 275