xref: /netbsd-src/sys/external/bsd/drm2/dist/drm/amd/amdgpu/amdgpu_ih.c (revision 627f7eb200a4419d89b531d55fccd2ee3ffdcde0)
1 /*	$NetBSD: amdgpu_ih.c,v 1.4 2020/02/14 14:34:58 maya 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 1.4 2020/02/14 14:34:58 maya Exp $");
28 
29 #include <drm/drmP.h>
30 #include "amdgpu.h"
31 #include "amdgpu_ih.h"
32 #include "amdgpu_amdkfd.h"
33 
34 /**
35  * amdgpu_ih_ring_alloc - allocate memory for the IH ring
36  *
37  * @adev: amdgpu_device pointer
38  *
39  * Allocate a ring buffer for the interrupt controller.
40  * Returns 0 for success, errors for failure.
41  */
42 static int amdgpu_ih_ring_alloc(struct amdgpu_device *adev)
43 {
44 	int r;
45 
46 	/* Allocate ring buffer */
47 	if (adev->irq.ih.ring_obj == NULL) {
48 		r = amdgpu_bo_create(adev, adev->irq.ih.ring_size,
49 				     PAGE_SIZE, true,
50 				     AMDGPU_GEM_DOMAIN_GTT, 0,
51 				     NULL, NULL, &adev->irq.ih.ring_obj);
52 		if (r) {
53 			DRM_ERROR("amdgpu: failed to create ih ring buffer (%d).\n", r);
54 			return r;
55 		}
56 		r = amdgpu_bo_reserve(adev->irq.ih.ring_obj, false);
57 		if (unlikely(r != 0))
58 			return r;
59 		r = amdgpu_bo_pin(adev->irq.ih.ring_obj,
60 				  AMDGPU_GEM_DOMAIN_GTT,
61 				  &adev->irq.ih.gpu_addr);
62 		if (r) {
63 			amdgpu_bo_unreserve(adev->irq.ih.ring_obj);
64 			DRM_ERROR("amdgpu: failed to pin ih ring buffer (%d).\n", r);
65 			return r;
66 		}
67 		r = amdgpu_bo_kmap(adev->irq.ih.ring_obj,
68 				   (void **)__UNVOLATILE(&adev->irq.ih.ring));
69 		amdgpu_bo_unreserve(adev->irq.ih.ring_obj);
70 		if (r) {
71 			DRM_ERROR("amdgpu: failed to map ih ring buffer (%d).\n", r);
72 			return r;
73 		}
74 	}
75 	return 0;
76 }
77 
78 /**
79  * amdgpu_ih_ring_init - initialize the IH state
80  *
81  * @adev: amdgpu_device pointer
82  *
83  * Initializes the IH state and allocates a buffer
84  * for the IH ring buffer.
85  * Returns 0 for success, errors for failure.
86  */
87 int amdgpu_ih_ring_init(struct amdgpu_device *adev, unsigned ring_size,
88 			bool use_bus_addr)
89 {
90 	u32 rb_bufsz;
91 	int r;
92 
93 	/* Align ring size */
94 	rb_bufsz = order_base_2(ring_size / 4);
95 	ring_size = (1 << rb_bufsz) * 4;
96 	adev->irq.ih.ring_size = ring_size;
97 	adev->irq.ih.ptr_mask = adev->irq.ih.ring_size - 1;
98 	adev->irq.ih.rptr = 0;
99 	adev->irq.ih.use_bus_addr = use_bus_addr;
100 
101 	if (adev->irq.ih.use_bus_addr) {
102 		if (!adev->irq.ih.ring) {
103 			/* add 8 bytes for the rptr/wptr shadows and
104 			 * add them to the end of the ring allocation.
105 			 */
106 #ifdef __NetBSD__
107 			const bus_size_t size = adev->irq.ih.ring_size + 8;
108 			int rseg __diagused;
109 			void *kva;
110 			r = -bus_dmamem_alloc(adev->ddev->dmat, size,
111 			    PAGE_SIZE, 0, &adev->irq.ih.ring_seg, 1, &rseg,
112 			    BUS_DMA_WAITOK);
113 			if (r) {
114 fail0:				KASSERT(r);
115 				return r;
116 			}
117 			KASSERT(rseg == 0);
118 			r = -bus_dmamap_create(adev->ddev->dmat, size, 1,
119 			    PAGE_SIZE, 0, BUS_DMA_WAITOK,
120 			    &adev->irq.ih.ring_map);
121 			if (r) {
122 fail1:				bus_dmamem_free(adev->ddev->dmat,
123 				    &adev->irq.ih.ring_seg, 1);
124 				goto fail0;
125 			}
126 			r = -bus_dmamem_map(adev->ddev->dmat,
127 			    &adev->irq.ih.ring_seg, 1, size, &kva,
128 			    BUS_DMA_WAITOK);
129 			if (r) {
130 fail2:				bus_dmamap_destroy(adev->ddev->dmat,
131 				    adev->irq.ih.ring_map);
132 				adev->irq.ih.ring_map = NULL;
133 				goto fail1;
134 			}
135 			r = -bus_dmamap_load(adev->ddev->dmat,
136 			    adev->irq.ih.ring_map, kva, size, NULL,
137 			    BUS_DMA_WAITOK);
138 			if (r) {
139 fail3: __unused			bus_dmamem_unmap(adev->ddev->dmat, kva, size);
140 				goto fail2;
141 			}
142 			adev->irq.ih.ring = kva;
143 			adev->irq.ih.rb_dma_addr =
144 			    adev->irq.ih.ring_map->dm_segs[0].ds_addr;
145 #else
146 			adev->irq.ih.ring = pci_alloc_consistent(adev->pdev,
147 								 adev->irq.ih.ring_size + 8,
148 								 &adev->irq.ih.rb_dma_addr);
149 			if (adev->irq.ih.ring == NULL)
150 				return -ENOMEM;
151 #endif
152 			memset(__UNVOLATILE(adev->irq.ih.ring), 0, adev->irq.ih.ring_size + 8);
153 			adev->irq.ih.wptr_offs = (adev->irq.ih.ring_size / 4) + 0;
154 			adev->irq.ih.rptr_offs = (adev->irq.ih.ring_size / 4) + 1;
155 		}
156 		return 0;
157 	} else {
158 		r = amdgpu_wb_get(adev, &adev->irq.ih.wptr_offs);
159 		if (r) {
160 			dev_err(adev->dev, "(%d) ih wptr_offs wb alloc failed\n", r);
161 			return r;
162 		}
163 
164 		r = amdgpu_wb_get(adev, &adev->irq.ih.rptr_offs);
165 		if (r) {
166 			amdgpu_wb_free(adev, adev->irq.ih.wptr_offs);
167 			dev_err(adev->dev, "(%d) ih rptr_offs wb alloc failed\n", r);
168 			return r;
169 		}
170 
171 		return amdgpu_ih_ring_alloc(adev);
172 	}
173 }
174 
175 /**
176  * amdgpu_ih_ring_fini - tear down the IH state
177  *
178  * @adev: amdgpu_device pointer
179  *
180  * Tears down the IH state and frees buffer
181  * used for the IH ring buffer.
182  */
183 void amdgpu_ih_ring_fini(struct amdgpu_device *adev)
184 {
185 	int r;
186 
187 	if (adev->irq.ih.use_bus_addr) {
188 		if (adev->irq.ih.ring) {
189 			/* add 8 bytes for the rptr/wptr shadows and
190 			 * add them to the end of the ring allocation.
191 			 */
192 #ifdef __NetBSD__
193 			const bus_size_t size = adev->irq.ih.ring_size + 8;
194 			void *kva = __UNVOLATILE(adev->irq.ih.ring);
195 			bus_dmamap_unload(adev->ddev->dmat,
196 			    adev->irq.ih.ring_map);
197 			bus_dmamem_unmap(adev->ddev->dmat, kva, size);
198 			bus_dmamap_destroy(adev->ddev->dmat,
199 			    adev->irq.ih.ring_map);
200 			bus_dmamem_free(adev->ddev->dmat,
201 			    &adev->irq.ih.ring_seg, 1);
202 #else
203 			pci_free_consistent(adev->pdev, adev->irq.ih.ring_size + 8,
204 					    (void *)adev->irq.ih.ring,
205 					    adev->irq.ih.rb_dma_addr);
206 #endif
207 			adev->irq.ih.ring = NULL;
208 		}
209 	} else {
210 		if (adev->irq.ih.ring_obj) {
211 			r = amdgpu_bo_reserve(adev->irq.ih.ring_obj, false);
212 			if (likely(r == 0)) {
213 				amdgpu_bo_kunmap(adev->irq.ih.ring_obj);
214 				amdgpu_bo_unpin(adev->irq.ih.ring_obj);
215 				amdgpu_bo_unreserve(adev->irq.ih.ring_obj);
216 			}
217 			amdgpu_bo_unref(&adev->irq.ih.ring_obj);
218 			adev->irq.ih.ring = NULL;
219 			adev->irq.ih.ring_obj = NULL;
220 		}
221 		amdgpu_wb_free(adev, adev->irq.ih.wptr_offs);
222 		amdgpu_wb_free(adev, adev->irq.ih.rptr_offs);
223 	}
224 }
225 
226 /**
227  * amdgpu_ih_process - interrupt handler
228  *
229  * @adev: amdgpu_device pointer
230  *
231  * Interrupt hander (VI), walk the IH ring.
232  * Returns irq process return code.
233  */
234 int amdgpu_ih_process(struct amdgpu_device *adev)
235 {
236 	struct amdgpu_iv_entry entry;
237 	u32 wptr;
238 
239 	if (!adev->irq.ih.enabled || adev->shutdown)
240 		return IRQ_NONE;
241 
242 	wptr = amdgpu_ih_get_wptr(adev);
243 
244 restart_ih:
245 	/* is somebody else already processing irqs? */
246 	if (atomic_xchg(&adev->irq.ih.lock, 1))
247 		return IRQ_NONE;
248 
249 	DRM_DEBUG("%s: rptr %d, wptr %d\n", __func__, adev->irq.ih.rptr, wptr);
250 
251 	/* Order reading of wptr vs. reading of IH ring data */
252 	rmb();
253 
254 	while (adev->irq.ih.rptr != wptr) {
255 		u32 ring_index = adev->irq.ih.rptr >> 2;
256 
257 		/* Before dispatching irq to IP blocks, send it to amdkfd */
258 		amdgpu_amdkfd_interrupt(adev,
259 				(const void *)__UNVOLATILE(&adev->irq.ih.ring[ring_index]));
260 
261 		entry.iv_entry = (const uint32_t *)
262 			__UNVOLATILE(&adev->irq.ih.ring[ring_index]);
263 		amdgpu_ih_decode_iv(adev, &entry);
264 		adev->irq.ih.rptr &= adev->irq.ih.ptr_mask;
265 
266 		amdgpu_irq_dispatch(adev, &entry);
267 	}
268 	amdgpu_ih_set_rptr(adev);
269 	atomic_set(&adev->irq.ih.lock, 0);
270 
271 	/* make sure wptr hasn't changed while processing */
272 	wptr = amdgpu_ih_get_wptr(adev);
273 	if (wptr != adev->irq.ih.rptr)
274 		goto restart_ih;
275 
276 	return IRQ_HANDLED;
277 }
278