xref: /netbsd-src/sys/external/bsd/drm2/dist/drm/amd/amdgpu/amdgpu_ih.c (revision 7330f729ccf0bd976a06f95fad452fe774fc7fd1)
1 /*	$NetBSD: amdgpu_ih.c,v 1.3 2018/08/27 14:04:50 riastradh Exp $	*/
2 
3 /*
4  * Copyright 2014 Advanced Micro Devices, Inc.
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a
7  * copy of this software and associated documentation files (the "Software"),
8  * to deal in the Software without restriction, including without limitation
9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10  * and/or sell copies of the Software, and to permit persons to whom the
11  * Software is furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
19  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
20  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22  * OTHER DEALINGS IN THE SOFTWARE.
23  *
24  */
25 
26 #include <sys/cdefs.h>
27 __KERNEL_RCSID(0, "$NetBSD: amdgpu_ih.c,v 1.3 2018/08/27 14:04:50 riastradh Exp $");
28 
29 #include <linux/log2.h>
30 #include <drm/drmP.h>
31 #include "amdgpu.h"
32 #include "amdgpu_ih.h"
33 #include "amdgpu_amdkfd.h"
34 
35 /**
36  * amdgpu_ih_ring_alloc - allocate memory for the IH ring
37  *
38  * @adev: amdgpu_device pointer
39  *
40  * Allocate a ring buffer for the interrupt controller.
41  * Returns 0 for success, errors for failure.
42  */
43 static int amdgpu_ih_ring_alloc(struct amdgpu_device *adev)
44 {
45 	int r;
46 
47 	/* Allocate ring buffer */
48 	if (adev->irq.ih.ring_obj == NULL) {
49 		r = amdgpu_bo_create(adev, adev->irq.ih.ring_size,
50 				     PAGE_SIZE, true,
51 				     AMDGPU_GEM_DOMAIN_GTT, 0,
52 				     NULL, NULL, &adev->irq.ih.ring_obj);
53 		if (r) {
54 			DRM_ERROR("amdgpu: failed to create ih ring buffer (%d).\n", r);
55 			return r;
56 		}
57 		r = amdgpu_bo_reserve(adev->irq.ih.ring_obj, false);
58 		if (unlikely(r != 0))
59 			return r;
60 		r = amdgpu_bo_pin(adev->irq.ih.ring_obj,
61 				  AMDGPU_GEM_DOMAIN_GTT,
62 				  &adev->irq.ih.gpu_addr);
63 		if (r) {
64 			amdgpu_bo_unreserve(adev->irq.ih.ring_obj);
65 			DRM_ERROR("amdgpu: failed to pin ih ring buffer (%d).\n", r);
66 			return r;
67 		}
68 		r = amdgpu_bo_kmap(adev->irq.ih.ring_obj,
69 				   (void **)__UNVOLATILE(&adev->irq.ih.ring));
70 		amdgpu_bo_unreserve(adev->irq.ih.ring_obj);
71 		if (r) {
72 			DRM_ERROR("amdgpu: failed to map ih ring buffer (%d).\n", r);
73 			return r;
74 		}
75 	}
76 	return 0;
77 }
78 
79 /**
80  * amdgpu_ih_ring_init - initialize the IH state
81  *
82  * @adev: amdgpu_device pointer
83  *
84  * Initializes the IH state and allocates a buffer
85  * for the IH ring buffer.
86  * Returns 0 for success, errors for failure.
87  */
88 int amdgpu_ih_ring_init(struct amdgpu_device *adev, unsigned ring_size,
89 			bool use_bus_addr)
90 {
91 	u32 rb_bufsz;
92 	int r;
93 
94 	/* Align ring size */
95 	rb_bufsz = order_base_2(ring_size / 4);
96 	ring_size = (1 << rb_bufsz) * 4;
97 	adev->irq.ih.ring_size = ring_size;
98 	adev->irq.ih.ptr_mask = adev->irq.ih.ring_size - 1;
99 	adev->irq.ih.rptr = 0;
100 	adev->irq.ih.use_bus_addr = use_bus_addr;
101 
102 	if (adev->irq.ih.use_bus_addr) {
103 		if (!adev->irq.ih.ring) {
104 			/* add 8 bytes for the rptr/wptr shadows and
105 			 * add them to the end of the ring allocation.
106 			 */
107 #ifdef __NetBSD__
108 			const bus_size_t size = adev->irq.ih.ring_size + 8;
109 			int rseg __diagused;
110 			void *kva;
111 			r = -bus_dmamem_alloc(adev->ddev->dmat, size,
112 			    PAGE_SIZE, 0, &adev->irq.ih.ring_seg, 1, &rseg,
113 			    BUS_DMA_WAITOK);
114 			if (r) {
115 fail0:				KASSERT(r);
116 				return r;
117 			}
118 			KASSERT(rseg == 0);
119 			r = -bus_dmamap_create(adev->ddev->dmat, size, 1,
120 			    PAGE_SIZE, 0, BUS_DMA_WAITOK,
121 			    &adev->irq.ih.ring_map);
122 			if (r) {
123 fail1:				bus_dmamem_free(adev->ddev->dmat,
124 				    &adev->irq.ih.ring_seg, 1);
125 				goto fail0;
126 			}
127 			r = -bus_dmamem_map(adev->ddev->dmat,
128 			    &adev->irq.ih.ring_seg, 1, size, &kva,
129 			    BUS_DMA_WAITOK);
130 			if (r) {
131 fail2:				bus_dmamap_destroy(adev->ddev->dmat,
132 				    adev->irq.ih.ring_map);
133 				adev->irq.ih.ring_map = NULL;
134 				goto fail1;
135 			}
136 			r = -bus_dmamap_load(adev->ddev->dmat,
137 			    adev->irq.ih.ring_map, kva, size, NULL,
138 			    BUS_DMA_WAITOK);
139 			if (r) {
140 fail3: __unused			bus_dmamem_unmap(adev->ddev->dmat, kva, size);
141 				goto fail2;
142 			}
143 			adev->irq.ih.ring = kva;
144 			adev->irq.ih.rb_dma_addr =
145 			    adev->irq.ih.ring_map->dm_segs[0].ds_addr;
146 #else
147 			adev->irq.ih.ring = pci_alloc_consistent(adev->pdev,
148 								 adev->irq.ih.ring_size + 8,
149 								 &adev->irq.ih.rb_dma_addr);
150 			if (adev->irq.ih.ring == NULL)
151 				return -ENOMEM;
152 #endif
153 			memset(__UNVOLATILE(adev->irq.ih.ring), 0, adev->irq.ih.ring_size + 8);
154 			adev->irq.ih.wptr_offs = (adev->irq.ih.ring_size / 4) + 0;
155 			adev->irq.ih.rptr_offs = (adev->irq.ih.ring_size / 4) + 1;
156 		}
157 		return 0;
158 	} else {
159 		r = amdgpu_wb_get(adev, &adev->irq.ih.wptr_offs);
160 		if (r) {
161 			dev_err(adev->dev, "(%d) ih wptr_offs wb alloc failed\n", r);
162 			return r;
163 		}
164 
165 		r = amdgpu_wb_get(adev, &adev->irq.ih.rptr_offs);
166 		if (r) {
167 			amdgpu_wb_free(adev, adev->irq.ih.wptr_offs);
168 			dev_err(adev->dev, "(%d) ih rptr_offs wb alloc failed\n", r);
169 			return r;
170 		}
171 
172 		return amdgpu_ih_ring_alloc(adev);
173 	}
174 }
175 
176 /**
177  * amdgpu_ih_ring_fini - tear down the IH state
178  *
179  * @adev: amdgpu_device pointer
180  *
181  * Tears down the IH state and frees buffer
182  * used for the IH ring buffer.
183  */
184 void amdgpu_ih_ring_fini(struct amdgpu_device *adev)
185 {
186 	int r;
187 
188 	if (adev->irq.ih.use_bus_addr) {
189 		if (adev->irq.ih.ring) {
190 			/* add 8 bytes for the rptr/wptr shadows and
191 			 * add them to the end of the ring allocation.
192 			 */
193 #ifdef __NetBSD__
194 			const bus_size_t size = adev->irq.ih.ring_size + 8;
195 			void *kva = __UNVOLATILE(adev->irq.ih.ring);
196 			bus_dmamap_unload(adev->ddev->dmat,
197 			    adev->irq.ih.ring_map);
198 			bus_dmamem_unmap(adev->ddev->dmat, kva, size);
199 			bus_dmamap_destroy(adev->ddev->dmat,
200 			    adev->irq.ih.ring_map);
201 			bus_dmamem_free(adev->ddev->dmat,
202 			    &adev->irq.ih.ring_seg, 1);
203 #else
204 			pci_free_consistent(adev->pdev, adev->irq.ih.ring_size + 8,
205 					    (void *)adev->irq.ih.ring,
206 					    adev->irq.ih.rb_dma_addr);
207 #endif
208 			adev->irq.ih.ring = NULL;
209 		}
210 	} else {
211 		if (adev->irq.ih.ring_obj) {
212 			r = amdgpu_bo_reserve(adev->irq.ih.ring_obj, false);
213 			if (likely(r == 0)) {
214 				amdgpu_bo_kunmap(adev->irq.ih.ring_obj);
215 				amdgpu_bo_unpin(adev->irq.ih.ring_obj);
216 				amdgpu_bo_unreserve(adev->irq.ih.ring_obj);
217 			}
218 			amdgpu_bo_unref(&adev->irq.ih.ring_obj);
219 			adev->irq.ih.ring = NULL;
220 			adev->irq.ih.ring_obj = NULL;
221 		}
222 		amdgpu_wb_free(adev, adev->irq.ih.wptr_offs);
223 		amdgpu_wb_free(adev, adev->irq.ih.rptr_offs);
224 	}
225 }
226 
227 /**
228  * amdgpu_ih_process - interrupt handler
229  *
230  * @adev: amdgpu_device pointer
231  *
232  * Interrupt hander (VI), walk the IH ring.
233  * Returns irq process return code.
234  */
235 int amdgpu_ih_process(struct amdgpu_device *adev)
236 {
237 	struct amdgpu_iv_entry entry;
238 	u32 wptr;
239 
240 	if (!adev->irq.ih.enabled || adev->shutdown)
241 		return IRQ_NONE;
242 
243 	wptr = amdgpu_ih_get_wptr(adev);
244 
245 restart_ih:
246 	/* is somebody else already processing irqs? */
247 	if (atomic_xchg(&adev->irq.ih.lock, 1))
248 		return IRQ_NONE;
249 
250 	DRM_DEBUG("%s: rptr %d, wptr %d\n", __func__, adev->irq.ih.rptr, wptr);
251 
252 	/* Order reading of wptr vs. reading of IH ring data */
253 	rmb();
254 
255 	while (adev->irq.ih.rptr != wptr) {
256 		u32 ring_index = adev->irq.ih.rptr >> 2;
257 
258 		/* Before dispatching irq to IP blocks, send it to amdkfd */
259 		amdgpu_amdkfd_interrupt(adev,
260 				(const void *)__UNVOLATILE(&adev->irq.ih.ring[ring_index]));
261 
262 		entry.iv_entry = (const uint32_t *)
263 			__UNVOLATILE(&adev->irq.ih.ring[ring_index]);
264 		amdgpu_ih_decode_iv(adev, &entry);
265 		adev->irq.ih.rptr &= adev->irq.ih.ptr_mask;
266 
267 		amdgpu_irq_dispatch(adev, &entry);
268 	}
269 	amdgpu_ih_set_rptr(adev);
270 	atomic_set(&adev->irq.ih.lock, 0);
271 
272 	/* make sure wptr hasn't changed while processing */
273 	wptr = amdgpu_ih_get_wptr(adev);
274 	if (wptr != adev->irq.ih.rptr)
275 		goto restart_ih;
276 
277 	return IRQ_HANDLED;
278 }
279