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 <linux/dma-mapping.h>
25
26#include "amdgpu.h"
27#include "amdgpu_ih.h"
28
29/**
30 * amdgpu_ih_ring_init - initialize the IH state
31 *
32 * @adev: amdgpu_device pointer
33 * @ih: ih ring to initialize
34 * @ring_size: ring size to allocate
35 * @use_bus_addr: true when we can use dma_alloc_coherent
36 *
37 * Initializes the IH state and allocates a buffer
38 * for the IH ring buffer.
39 * Returns 0 for success, errors for failure.
40 */
41int amdgpu_ih_ring_init(struct amdgpu_device *adev, struct amdgpu_ih_ring *ih,
42 unsigned ring_size, bool use_bus_addr)
43{
44 u32 rb_bufsz;
45 int r;
46
47 /* Align ring size */
48 rb_bufsz = order_base_2(ring_size / 4);
49 ring_size = (1 << rb_bufsz) * 4;
50 ih->ring_size = ring_size;
51 ih->ptr_mask = ih->ring_size - 1;
52 ih->rptr = 0;
53 ih->use_bus_addr = use_bus_addr;
54
55 if (use_bus_addr) {
56 dma_addr_t dma_addr;
57
58 if (ih->ring)
59 return 0;
60
61 /* add 8 bytes for the rptr/wptr shadows and
62 * add them to the end of the ring allocation.
63 */
64 ih->ring = dma_alloc_coherent(dev: adev->dev, size: ih->ring_size + 8,
65 dma_handle: &dma_addr, GFP_KERNEL);
66 if (ih->ring == NULL)
67 return -ENOMEM;
68
69 ih->gpu_addr = dma_addr;
70 ih->wptr_addr = dma_addr + ih->ring_size;
71 ih->wptr_cpu = &ih->ring[ih->ring_size / 4];
72 ih->rptr_addr = dma_addr + ih->ring_size + 4;
73 ih->rptr_cpu = &ih->ring[(ih->ring_size / 4) + 1];
74 } else {
75 unsigned wptr_offs, rptr_offs;
76
77 r = amdgpu_device_wb_get(adev, wb: &wptr_offs);
78 if (r)
79 return r;
80
81 r = amdgpu_device_wb_get(adev, wb: &rptr_offs);
82 if (r) {
83 amdgpu_device_wb_free(adev, wb: wptr_offs);
84 return r;
85 }
86
87 r = amdgpu_bo_create_kernel(adev, size: ih->ring_size, PAGE_SIZE,
88 AMDGPU_GEM_DOMAIN_GTT,
89 bo_ptr: &ih->ring_obj, gpu_addr: &ih->gpu_addr,
90 cpu_addr: (void **)&ih->ring);
91 if (r) {
92 amdgpu_device_wb_free(adev, wb: rptr_offs);
93 amdgpu_device_wb_free(adev, wb: wptr_offs);
94 return r;
95 }
96
97 ih->wptr_addr = adev->wb.gpu_addr + wptr_offs * 4;
98 ih->wptr_cpu = &adev->wb.wb[wptr_offs];
99 ih->rptr_addr = adev->wb.gpu_addr + rptr_offs * 4;
100 ih->rptr_cpu = &adev->wb.wb[rptr_offs];
101 }
102
103 init_waitqueue_head(&ih->wait_process);
104 return 0;
105}
106
107/**
108 * amdgpu_ih_ring_fini - tear down the IH state
109 *
110 * @adev: amdgpu_device pointer
111 * @ih: ih ring to tear down
112 *
113 * Tears down the IH state and frees buffer
114 * used for the IH ring buffer.
115 */
116void amdgpu_ih_ring_fini(struct amdgpu_device *adev, struct amdgpu_ih_ring *ih)
117{
118
119 if (!ih->ring)
120 return;
121
122 if (ih->use_bus_addr) {
123
124 /* add 8 bytes for the rptr/wptr shadows and
125 * add them to the end of the ring allocation.
126 */
127 dma_free_coherent(dev: adev->dev, size: ih->ring_size + 8,
128 cpu_addr: (void *)ih->ring, dma_handle: ih->gpu_addr);
129 ih->ring = NULL;
130 } else {
131 amdgpu_bo_free_kernel(bo: &ih->ring_obj, gpu_addr: &ih->gpu_addr,
132 cpu_addr: (void **)&ih->ring);
133 amdgpu_device_wb_free(adev, wb: (ih->wptr_addr - ih->gpu_addr) / 4);
134 amdgpu_device_wb_free(adev, wb: (ih->rptr_addr - ih->gpu_addr) / 4);
135 }
136}
137
138/**
139 * amdgpu_ih_ring_write - write IV to the ring buffer
140 *
141 * @adev: amdgpu_device pointer
142 * @ih: ih ring to write to
143 * @iv: the iv to write
144 * @num_dw: size of the iv in dw
145 *
146 * Writes an IV to the ring buffer using the CPU and increment the wptr.
147 * Used for testing and delegating IVs to a software ring.
148 */
149void amdgpu_ih_ring_write(struct amdgpu_device *adev, struct amdgpu_ih_ring *ih,
150 const uint32_t *iv, unsigned int num_dw)
151{
152 uint32_t wptr = le32_to_cpu(*ih->wptr_cpu) >> 2;
153 unsigned int i;
154
155 for (i = 0; i < num_dw; ++i)
156 ih->ring[wptr++] = cpu_to_le32(iv[i]);
157
158 wptr <<= 2;
159 wptr &= ih->ptr_mask;
160
161 /* Only commit the new wptr if we don't overflow */
162 if (wptr != READ_ONCE(ih->rptr)) {
163 wmb();
164 WRITE_ONCE(*ih->wptr_cpu, cpu_to_le32(wptr));
165 } else if (adev->irq.retry_cam_enabled) {
166 dev_warn_once(adev->dev, "IH soft ring buffer overflow 0x%X, 0x%X\n",
167 wptr, ih->rptr);
168 }
169}
170
171/**
172 * amdgpu_ih_wait_on_checkpoint_process_ts - wait to process IVs up to checkpoint
173 *
174 * @adev: amdgpu_device pointer
175 * @ih: ih ring to process
176 *
177 * Used to ensure ring has processed IVs up to the checkpoint write pointer.
178 */
179int amdgpu_ih_wait_on_checkpoint_process_ts(struct amdgpu_device *adev,
180 struct amdgpu_ih_ring *ih)
181{
182 uint32_t checkpoint_wptr;
183 uint64_t checkpoint_ts;
184 long timeout = HZ;
185
186 if (!ih->enabled || adev->shutdown)
187 return -ENODEV;
188
189 checkpoint_wptr = amdgpu_ih_get_wptr(adev, ih);
190 /* Order wptr with ring data. */
191 rmb();
192 checkpoint_ts = amdgpu_ih_decode_iv_ts(adev, ih, checkpoint_wptr, -1);
193
194 return wait_event_interruptible_timeout(ih->wait_process,
195 amdgpu_ih_ts_after(checkpoint_ts, ih->processed_timestamp) ||
196 ih->rptr == amdgpu_ih_get_wptr(adev, ih), timeout);
197}
198
199/**
200 * amdgpu_ih_process - interrupt handler
201 *
202 * @adev: amdgpu_device pointer
203 * @ih: ih ring to process
204 *
205 * Interrupt hander (VI), walk the IH ring.
206 * Returns irq process return code.
207 */
208int amdgpu_ih_process(struct amdgpu_device *adev, struct amdgpu_ih_ring *ih)
209{
210 unsigned int count;
211 u32 wptr;
212
213 if (!ih->enabled || adev->shutdown)
214 return IRQ_NONE;
215
216 wptr = amdgpu_ih_get_wptr(adev, ih);
217
218restart_ih:
219 count = AMDGPU_IH_MAX_NUM_IVS;
220 DRM_DEBUG("%s: rptr %d, wptr %d\n", __func__, ih->rptr, wptr);
221
222 /* Order reading of wptr vs. reading of IH ring data */
223 rmb();
224
225 while (ih->rptr != wptr && --count) {
226 amdgpu_irq_dispatch(adev, ih);
227 ih->rptr &= ih->ptr_mask;
228 }
229
230 amdgpu_ih_set_rptr(adev, ih);
231 wake_up_all(&ih->wait_process);
232
233 /* make sure wptr hasn't changed while processing */
234 wptr = amdgpu_ih_get_wptr(adev, ih);
235 if (wptr != ih->rptr)
236 goto restart_ih;
237
238 return IRQ_HANDLED;
239}
240
241/**
242 * amdgpu_ih_decode_iv_helper - decode an interrupt vector
243 *
244 * @adev: amdgpu_device pointer
245 * @ih: ih ring to process
246 * @entry: IV entry
247 *
248 * Decodes the interrupt vector at the current rptr
249 * position and also advance the position for Vega10
250 * and later GPUs.
251 */
252void amdgpu_ih_decode_iv_helper(struct amdgpu_device *adev,
253 struct amdgpu_ih_ring *ih,
254 struct amdgpu_iv_entry *entry)
255{
256 /* wptr/rptr are in bytes! */
257 u32 ring_index = ih->rptr >> 2;
258 uint32_t dw[8];
259
260 dw[0] = le32_to_cpu(ih->ring[ring_index + 0]);
261 dw[1] = le32_to_cpu(ih->ring[ring_index + 1]);
262 dw[2] = le32_to_cpu(ih->ring[ring_index + 2]);
263 dw[3] = le32_to_cpu(ih->ring[ring_index + 3]);
264 dw[4] = le32_to_cpu(ih->ring[ring_index + 4]);
265 dw[5] = le32_to_cpu(ih->ring[ring_index + 5]);
266 dw[6] = le32_to_cpu(ih->ring[ring_index + 6]);
267 dw[7] = le32_to_cpu(ih->ring[ring_index + 7]);
268
269 entry->client_id = dw[0] & 0xff;
270 entry->src_id = (dw[0] >> 8) & 0xff;
271 entry->ring_id = (dw[0] >> 16) & 0xff;
272 entry->vmid = (dw[0] >> 24) & 0xf;
273 entry->vmid_src = (dw[0] >> 31);
274 entry->timestamp = dw[1] | ((u64)(dw[2] & 0xffff) << 32);
275 entry->timestamp_src = dw[2] >> 31;
276 entry->pasid = dw[3] & 0xffff;
277 entry->node_id = (dw[3] >> 16) & 0xff;
278 entry->src_data[0] = dw[4];
279 entry->src_data[1] = dw[5];
280 entry->src_data[2] = dw[6];
281 entry->src_data[3] = dw[7];
282
283 /* wptr/rptr are in bytes! */
284 ih->rptr += 32;
285}
286
287uint64_t amdgpu_ih_decode_iv_ts_helper(struct amdgpu_ih_ring *ih, u32 rptr,
288 signed int offset)
289{
290 uint32_t iv_size = 32;
291 uint32_t ring_index;
292 uint32_t dw1, dw2;
293
294 rptr += iv_size * offset;
295 ring_index = (rptr & ih->ptr_mask) >> 2;
296
297 dw1 = le32_to_cpu(ih->ring[ring_index + 1]);
298 dw2 = le32_to_cpu(ih->ring[ring_index + 2]);
299 return dw1 | ((u64)(dw2 & 0xffff) << 32);
300}
301

source code of linux/drivers/gpu/drm/amd/amdgpu/amdgpu_ih.c