xref: /linux/drivers/gpu/drm/xe/xe_memirq.c (revision 3269d6fb7580e91313f40dffcff70c01cd3f0717)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2023 Intel Corporation
4  */
5 
6 #include <drm/drm_managed.h>
7 
8 #include "regs/xe_gt_regs.h"
9 #include "regs/xe_guc_regs.h"
10 #include "regs/xe_regs.h"
11 
12 #include "xe_assert.h"
13 #include "xe_bo.h"
14 #include "xe_device.h"
15 #include "xe_device_types.h"
16 #include "xe_gt.h"
17 #include "xe_gt_printk.h"
18 #include "xe_guc.h"
19 #include "xe_hw_engine.h"
20 #include "xe_map.h"
21 #include "xe_memirq.h"
22 #include "xe_sriov.h"
23 #include "xe_sriov_printk.h"
24 
25 #define memirq_assert(m, condition)	xe_tile_assert(memirq_to_tile(m), condition)
26 #define memirq_debug(m, msg...)		xe_sriov_dbg_verbose(memirq_to_xe(m), "MEMIRQ: " msg)
27 
28 static struct xe_tile *memirq_to_tile(struct xe_memirq *memirq)
29 {
30 	return container_of(memirq, struct xe_tile, sriov.vf.memirq);
31 }
32 
33 static struct xe_device *memirq_to_xe(struct xe_memirq *memirq)
34 {
35 	return tile_to_xe(memirq_to_tile(memirq));
36 }
37 
38 static const char *guc_name(struct xe_guc *guc)
39 {
40 	return xe_gt_is_media_type(guc_to_gt(guc)) ? "media GuC" : "GuC";
41 }
42 
43 /**
44  * DOC: Memory Based Interrupts
45  *
46  * MMIO register based interrupts infrastructure used for non-virtualized mode
47  * or SRIOV-8 (which supports 8 Virtual Functions) does not scale efficiently
48  * to allow delivering interrupts to a large number of Virtual machines or
49  * containers. Memory based interrupt status reporting provides an efficient
50  * and scalable infrastructure.
51  *
52  * For memory based interrupt status reporting hardware sequence is:
53  *  * Engine writes the interrupt event to memory
54  *    (Pointer to memory location is provided by SW. This memory surface must
55  *    be mapped to system memory and must be marked as un-cacheable (UC) on
56  *    Graphics IP Caches)
57  *  * Engine triggers an interrupt to host.
58  */
59 
60 /**
61  * DOC: Memory Based Interrupts Page Layout
62  *
63  * `Memory Based Interrupts`_ requires three different objects, which are
64  * called "page" in the specs, even if they aren't page-sized or aligned.
65  *
66  * To simplify the code we allocate a single page size object and then use
67  * offsets to embedded "pages". The address of those "pages" are then
68  * programmed in the HW via LRI and LRM in the context image.
69  *
70  * - _`Interrupt Status Report Page`: this page contains the interrupt
71  *   status vectors for each unit. Each bit in the interrupt vectors is
72  *   converted to a byte, with the byte being set to 0xFF when an
73  *   interrupt is triggered; interrupt vectors are 16b big so each unit
74  *   gets 16B. One space is reserved for each bit in one of the
75  *   GT_INTR_DWx registers, so this object needs a total of 1024B.
76  *   This object needs to be 4KiB aligned.
77  *
78  * - _`Interrupt Source Report Page`: this is the equivalent of the
79  *   GEN11_GT_INTR_DWx registers, with each bit in those registers being
80  *   mapped to a byte here. The offsets are the same, just bytes instead
81  *   of bits. This object needs to be cacheline aligned.
82  *
83  * - Interrupt Mask: the HW needs a location to fetch the interrupt
84  *   mask vector to be used by the LRM in the context, so we just use
85  *   the next available space in the interrupt page.
86  *
87  * ::
88  *
89  *   0x0000   +===========+  <== Interrupt Status Report Page
90  *            |           |
91  *            |           |     ____ +----+----------------+
92  *            |           |    /     |  0 | USER INTERRUPT |
93  *            +-----------+ __/      |  1 |                |
94  *            |  HWE(n)   | __       |    | CTX SWITCH     |
95  *            +-----------+   \      |    | WAIT SEMAPHORE |
96  *            |           |    \____ | 15 |                |
97  *            |           |          +----+----------------+
98  *            |           |
99  *   0x0400   +===========+  <== Interrupt Source Report Page
100  *            |  HWE(0)   |
101  *            |  HWE(1)   |
102  *            |           |
103  *            |  HWE(x)   |
104  *   0x0440   +===========+  <== Interrupt Enable Mask
105  *            |           |
106  *            |           |
107  *            +-----------+
108  */
109 
110 static void __release_xe_bo(struct drm_device *drm, void *arg)
111 {
112 	struct xe_bo *bo = arg;
113 
114 	xe_bo_unpin_map_no_vm(bo);
115 }
116 
117 static int memirq_alloc_pages(struct xe_memirq *memirq)
118 {
119 	struct xe_device *xe = memirq_to_xe(memirq);
120 	struct xe_tile *tile = memirq_to_tile(memirq);
121 	struct xe_bo *bo;
122 	int err;
123 
124 	BUILD_BUG_ON(!IS_ALIGNED(XE_MEMIRQ_SOURCE_OFFSET, SZ_64));
125 	BUILD_BUG_ON(!IS_ALIGNED(XE_MEMIRQ_STATUS_OFFSET, SZ_4K));
126 
127 	/* XXX: convert to managed bo */
128 	bo = xe_bo_create_pin_map(xe, tile, NULL, SZ_4K,
129 				  ttm_bo_type_kernel,
130 				  XE_BO_FLAG_SYSTEM |
131 				  XE_BO_FLAG_GGTT |
132 				  XE_BO_FLAG_GGTT_INVALIDATE |
133 				  XE_BO_FLAG_NEEDS_UC |
134 				  XE_BO_FLAG_NEEDS_CPU_ACCESS);
135 	if (IS_ERR(bo)) {
136 		err = PTR_ERR(bo);
137 		goto out;
138 	}
139 
140 	memirq_assert(memirq, !xe_bo_is_vram(bo));
141 	memirq_assert(memirq, !memirq->bo);
142 
143 	iosys_map_memset(&bo->vmap, 0, 0, SZ_4K);
144 
145 	memirq->bo = bo;
146 	memirq->source = IOSYS_MAP_INIT_OFFSET(&bo->vmap, XE_MEMIRQ_SOURCE_OFFSET);
147 	memirq->status = IOSYS_MAP_INIT_OFFSET(&bo->vmap, XE_MEMIRQ_STATUS_OFFSET);
148 	memirq->mask = IOSYS_MAP_INIT_OFFSET(&bo->vmap, XE_MEMIRQ_ENABLE_OFFSET);
149 
150 	memirq_assert(memirq, !memirq->source.is_iomem);
151 	memirq_assert(memirq, !memirq->status.is_iomem);
152 	memirq_assert(memirq, !memirq->mask.is_iomem);
153 
154 	memirq_debug(memirq, "page offsets: source %#x status %#x\n",
155 		     xe_memirq_source_ptr(memirq), xe_memirq_status_ptr(memirq));
156 
157 	return drmm_add_action_or_reset(&xe->drm, __release_xe_bo, memirq->bo);
158 
159 out:
160 	xe_sriov_err(memirq_to_xe(memirq),
161 		     "Failed to allocate memirq page (%pe)\n", ERR_PTR(err));
162 	return err;
163 }
164 
165 static void memirq_set_enable(struct xe_memirq *memirq, bool enable)
166 {
167 	iosys_map_wr(&memirq->mask, 0, u32, enable ? GENMASK(15, 0) : 0);
168 
169 	memirq->enabled = enable;
170 }
171 
172 /**
173  * xe_memirq_init - Initialize data used by `Memory Based Interrupts`_.
174  * @memirq: the &xe_memirq to initialize
175  *
176  * Allocate `Interrupt Source Report Page`_ and `Interrupt Status Report Page`_
177  * used by `Memory Based Interrupts`_.
178  *
179  * These allocations are managed and will be implicitly released on unload.
180  *
181  * Note: This function shall be called only by the VF driver.
182  *
183  * If this function fails then VF driver won't be able to operate correctly.
184  * If `Memory Based Interrupts`_ are not used this function will return 0.
185  *
186  * Return: 0 on success or a negative error code on failure.
187  */
188 int xe_memirq_init(struct xe_memirq *memirq)
189 {
190 	struct xe_device *xe = memirq_to_xe(memirq);
191 	int err;
192 
193 	memirq_assert(memirq, IS_SRIOV_VF(xe));
194 
195 	if (!xe_device_has_memirq(xe))
196 		return 0;
197 
198 	err = memirq_alloc_pages(memirq);
199 	if (unlikely(err))
200 		return err;
201 
202 	/* we need to start with all irqs enabled */
203 	memirq_set_enable(memirq, true);
204 
205 	return 0;
206 }
207 
208 /**
209  * xe_memirq_source_ptr - Get GGTT's offset of the `Interrupt Source Report Page`_.
210  * @memirq: the &xe_memirq to query
211  *
212  * Shall be called only on VF driver when `Memory Based Interrupts`_ are used
213  * and xe_memirq_init() didn't fail.
214  *
215  * Return: GGTT's offset of the `Interrupt Source Report Page`_.
216  */
217 u32 xe_memirq_source_ptr(struct xe_memirq *memirq)
218 {
219 	memirq_assert(memirq, IS_SRIOV_VF(memirq_to_xe(memirq)));
220 	memirq_assert(memirq, xe_device_has_memirq(memirq_to_xe(memirq)));
221 	memirq_assert(memirq, memirq->bo);
222 
223 	return xe_bo_ggtt_addr(memirq->bo) + XE_MEMIRQ_SOURCE_OFFSET;
224 }
225 
226 /**
227  * xe_memirq_status_ptr - Get GGTT's offset of the `Interrupt Status Report Page`_.
228  * @memirq: the &xe_memirq to query
229  *
230  * Shall be called only on VF driver when `Memory Based Interrupts`_ are used
231  * and xe_memirq_init() didn't fail.
232  *
233  * Return: GGTT's offset of the `Interrupt Status Report Page`_.
234  */
235 u32 xe_memirq_status_ptr(struct xe_memirq *memirq)
236 {
237 	memirq_assert(memirq, IS_SRIOV_VF(memirq_to_xe(memirq)));
238 	memirq_assert(memirq, xe_device_has_memirq(memirq_to_xe(memirq)));
239 	memirq_assert(memirq, memirq->bo);
240 
241 	return xe_bo_ggtt_addr(memirq->bo) + XE_MEMIRQ_STATUS_OFFSET;
242 }
243 
244 /**
245  * xe_memirq_enable_ptr - Get GGTT's offset of the Interrupt Enable Mask.
246  * @memirq: the &xe_memirq to query
247  *
248  * Shall be called only on VF driver when `Memory Based Interrupts`_ are used
249  * and xe_memirq_init() didn't fail.
250  *
251  * Return: GGTT's offset of the Interrupt Enable Mask.
252  */
253 u32 xe_memirq_enable_ptr(struct xe_memirq *memirq)
254 {
255 	memirq_assert(memirq, IS_SRIOV_VF(memirq_to_xe(memirq)));
256 	memirq_assert(memirq, xe_device_has_memirq(memirq_to_xe(memirq)));
257 	memirq_assert(memirq, memirq->bo);
258 
259 	return xe_bo_ggtt_addr(memirq->bo) + XE_MEMIRQ_ENABLE_OFFSET;
260 }
261 
262 /**
263  * xe_memirq_init_guc - Prepare GuC for `Memory Based Interrupts`_.
264  * @memirq: the &xe_memirq
265  * @guc: the &xe_guc to setup
266  *
267  * Register `Interrupt Source Report Page`_ and `Interrupt Status Report Page`_
268  * to be used by the GuC when `Memory Based Interrupts`_ are required.
269  *
270  * Shall be called only on VF driver when `Memory Based Interrupts`_ are used
271  * and xe_memirq_init() didn't fail.
272  *
273  * Return: 0 on success or a negative error code on failure.
274  */
275 int xe_memirq_init_guc(struct xe_memirq *memirq, struct xe_guc *guc)
276 {
277 	bool is_media = xe_gt_is_media_type(guc_to_gt(guc));
278 	u32 offset = is_media ? ilog2(INTR_MGUC) : ilog2(INTR_GUC);
279 	u32 source, status;
280 	int err;
281 
282 	memirq_assert(memirq, IS_SRIOV_VF(memirq_to_xe(memirq)));
283 	memirq_assert(memirq, xe_device_has_memirq(memirq_to_xe(memirq)));
284 	memirq_assert(memirq, memirq->bo);
285 
286 	source = xe_memirq_source_ptr(memirq) + offset;
287 	status = xe_memirq_status_ptr(memirq) + offset * SZ_16;
288 
289 	err = xe_guc_self_cfg64(guc, GUC_KLV_SELF_CFG_MEMIRQ_SOURCE_ADDR_KEY,
290 				source);
291 	if (unlikely(err))
292 		goto failed;
293 
294 	err = xe_guc_self_cfg64(guc, GUC_KLV_SELF_CFG_MEMIRQ_STATUS_ADDR_KEY,
295 				status);
296 	if (unlikely(err))
297 		goto failed;
298 
299 	return 0;
300 
301 failed:
302 	xe_sriov_err(memirq_to_xe(memirq),
303 		     "Failed to setup report pages in %s (%pe)\n",
304 		     guc_name(guc), ERR_PTR(err));
305 	return err;
306 }
307 
308 /**
309  * xe_memirq_reset - Disable processing of `Memory Based Interrupts`_.
310  * @memirq: struct xe_memirq
311  *
312  * This is part of the driver IRQ setup flow.
313  *
314  * This function shall only be used by the VF driver on platforms that use
315  * `Memory Based Interrupts`_.
316  */
317 void xe_memirq_reset(struct xe_memirq *memirq)
318 {
319 	memirq_assert(memirq, IS_SRIOV_VF(memirq_to_xe(memirq)));
320 	memirq_assert(memirq, xe_device_has_memirq(memirq_to_xe(memirq)));
321 
322 	if (memirq->bo)
323 		memirq_set_enable(memirq, false);
324 }
325 
326 /**
327  * xe_memirq_postinstall - Enable processing of `Memory Based Interrupts`_.
328  * @memirq: the &xe_memirq
329  *
330  * This is part of the driver IRQ setup flow.
331  *
332  * This function shall only be used by the VF driver on platforms that use
333  * `Memory Based Interrupts`_.
334  */
335 void xe_memirq_postinstall(struct xe_memirq *memirq)
336 {
337 	memirq_assert(memirq, IS_SRIOV_VF(memirq_to_xe(memirq)));
338 	memirq_assert(memirq, xe_device_has_memirq(memirq_to_xe(memirq)));
339 
340 	if (memirq->bo)
341 		memirq_set_enable(memirq, true);
342 }
343 
344 static bool memirq_received(struct xe_memirq *memirq, struct iosys_map *vector,
345 			    u16 offset, const char *name)
346 {
347 	u8 value;
348 
349 	value = iosys_map_rd(vector, offset, u8);
350 	if (value) {
351 		if (value != 0xff)
352 			xe_sriov_err_ratelimited(memirq_to_xe(memirq),
353 						 "Unexpected memirq value %#x from %s at %u\n",
354 						 value, name, offset);
355 		iosys_map_wr(vector, offset, u8, 0x00);
356 	}
357 
358 	return value;
359 }
360 
361 static void memirq_dispatch_engine(struct xe_memirq *memirq, struct iosys_map *status,
362 				   struct xe_hw_engine *hwe)
363 {
364 	memirq_debug(memirq, "STATUS %s %*ph\n", hwe->name, 16, status->vaddr);
365 
366 	if (memirq_received(memirq, status, ilog2(GT_RENDER_USER_INTERRUPT), hwe->name))
367 		xe_hw_engine_handle_irq(hwe, GT_RENDER_USER_INTERRUPT);
368 }
369 
370 static void memirq_dispatch_guc(struct xe_memirq *memirq, struct iosys_map *status,
371 				struct xe_guc *guc)
372 {
373 	const char *name = guc_name(guc);
374 
375 	memirq_debug(memirq, "STATUS %s %*ph\n", name, 16, status->vaddr);
376 
377 	if (memirq_received(memirq, status, ilog2(GUC_INTR_GUC2HOST), name))
378 		xe_guc_irq_handler(guc, GUC_INTR_GUC2HOST);
379 }
380 
381 /**
382  * xe_memirq_handler - The `Memory Based Interrupts`_ Handler.
383  * @memirq: the &xe_memirq
384  *
385  * This function reads and dispatches `Memory Based Interrupts`.
386  */
387 void xe_memirq_handler(struct xe_memirq *memirq)
388 {
389 	struct xe_device *xe = memirq_to_xe(memirq);
390 	struct xe_tile *tile = memirq_to_tile(memirq);
391 	struct xe_hw_engine *hwe;
392 	enum xe_hw_engine_id id;
393 	struct iosys_map map;
394 	unsigned int gtid;
395 	struct xe_gt *gt;
396 
397 	if (!memirq->bo)
398 		return;
399 
400 	memirq_assert(memirq, !memirq->source.is_iomem);
401 	memirq_debug(memirq, "SOURCE %*ph\n", 32, memirq->source.vaddr);
402 	memirq_debug(memirq, "SOURCE %*ph\n", 32, memirq->source.vaddr + 32);
403 
404 	for_each_gt(gt, xe, gtid) {
405 		if (gt->tile != tile)
406 			continue;
407 
408 		for_each_hw_engine(hwe, gt, id) {
409 			if (memirq_received(memirq, &memirq->source, hwe->irq_offset, "SRC")) {
410 				map = IOSYS_MAP_INIT_OFFSET(&memirq->status,
411 							    hwe->irq_offset * SZ_16);
412 				memirq_dispatch_engine(memirq, &map, hwe);
413 			}
414 		}
415 	}
416 
417 	/* GuC and media GuC (if present) must be checked separately */
418 
419 	if (memirq_received(memirq, &memirq->source, ilog2(INTR_GUC), "SRC")) {
420 		map = IOSYS_MAP_INIT_OFFSET(&memirq->status, ilog2(INTR_GUC) * SZ_16);
421 		memirq_dispatch_guc(memirq, &map, &tile->primary_gt->uc.guc);
422 	}
423 
424 	if (!tile->media_gt)
425 		return;
426 
427 	if (memirq_received(memirq, &memirq->source, ilog2(INTR_MGUC), "SRC")) {
428 		map = IOSYS_MAP_INIT_OFFSET(&memirq->status, ilog2(INTR_MGUC) * SZ_16);
429 		memirq_dispatch_guc(memirq, &map, &tile->media_gt->uc.guc);
430 	}
431 }
432