xref: /linux/drivers/gpu/drm/xe/xe_memirq.c (revision 06d07429858317ded2db7986113a9e0129cd599b)
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_CREATE_SYSTEM_BIT |
131 				  XE_BO_CREATE_GGTT_BIT |
132 				  XE_BO_NEEDS_UC |
133 				  XE_BO_NEEDS_CPU_ACCESS);
134 	if (IS_ERR(bo)) {
135 		err = PTR_ERR(bo);
136 		goto out;
137 	}
138 
139 	memirq_assert(memirq, !xe_bo_is_vram(bo));
140 	memirq_assert(memirq, !memirq->bo);
141 
142 	iosys_map_memset(&bo->vmap, 0, 0, SZ_4K);
143 
144 	memirq->bo = bo;
145 	memirq->source = IOSYS_MAP_INIT_OFFSET(&bo->vmap, XE_MEMIRQ_SOURCE_OFFSET);
146 	memirq->status = IOSYS_MAP_INIT_OFFSET(&bo->vmap, XE_MEMIRQ_STATUS_OFFSET);
147 	memirq->mask = IOSYS_MAP_INIT_OFFSET(&bo->vmap, XE_MEMIRQ_ENABLE_OFFSET);
148 
149 	memirq_assert(memirq, !memirq->source.is_iomem);
150 	memirq_assert(memirq, !memirq->status.is_iomem);
151 	memirq_assert(memirq, !memirq->mask.is_iomem);
152 
153 	memirq_debug(memirq, "page offsets: source %#x status %#x\n",
154 		     xe_memirq_source_ptr(memirq), xe_memirq_status_ptr(memirq));
155 
156 	return drmm_add_action_or_reset(&xe->drm, __release_xe_bo, memirq->bo);
157 
158 out:
159 	xe_sriov_err(memirq_to_xe(memirq),
160 		     "Failed to allocate memirq page (%pe)\n", ERR_PTR(err));
161 	return err;
162 }
163 
164 static void memirq_set_enable(struct xe_memirq *memirq, bool enable)
165 {
166 	iosys_map_wr(&memirq->mask, 0, u32, enable ? GENMASK(15, 0) : 0);
167 
168 	memirq->enabled = enable;
169 }
170 
171 /**
172  * xe_memirq_init - Initialize data used by `Memory Based Interrupts`_.
173  * @memirq: the &xe_memirq to initialize
174  *
175  * Allocate `Interrupt Source Report Page`_ and `Interrupt Status Report Page`_
176  * used by `Memory Based Interrupts`_.
177  *
178  * These allocations are managed and will be implicitly released on unload.
179  *
180  * Note: This function shall be called only by the VF driver.
181  *
182  * If this function fails then VF driver won't be able to operate correctly.
183  * If `Memory Based Interrupts`_ are not used this function will return 0.
184  *
185  * Return: 0 on success or a negative error code on failure.
186  */
187 int xe_memirq_init(struct xe_memirq *memirq)
188 {
189 	struct xe_device *xe = memirq_to_xe(memirq);
190 	int err;
191 
192 	memirq_assert(memirq, IS_SRIOV_VF(xe));
193 
194 	if (!xe_device_has_memirq(xe))
195 		return 0;
196 
197 	err = memirq_alloc_pages(memirq);
198 	if (unlikely(err))
199 		return err;
200 
201 	/* we need to start with all irqs enabled */
202 	memirq_set_enable(memirq, true);
203 
204 	return 0;
205 }
206 
207 /**
208  * xe_memirq_source_ptr - Get GGTT's offset of the `Interrupt Source Report Page`_.
209  * @memirq: the &xe_memirq to query
210  *
211  * Shall be called only on VF driver when `Memory Based Interrupts`_ are used
212  * and xe_memirq_init() didn't fail.
213  *
214  * Return: GGTT's offset of the `Interrupt Source Report Page`_.
215  */
216 u32 xe_memirq_source_ptr(struct xe_memirq *memirq)
217 {
218 	memirq_assert(memirq, IS_SRIOV_VF(memirq_to_xe(memirq)));
219 	memirq_assert(memirq, xe_device_has_memirq(memirq_to_xe(memirq)));
220 	memirq_assert(memirq, memirq->bo);
221 
222 	return xe_bo_ggtt_addr(memirq->bo) + XE_MEMIRQ_SOURCE_OFFSET;
223 }
224 
225 /**
226  * xe_memirq_status_ptr - Get GGTT's offset of the `Interrupt Status Report Page`_.
227  * @memirq: the &xe_memirq to query
228  *
229  * Shall be called only on VF driver when `Memory Based Interrupts`_ are used
230  * and xe_memirq_init() didn't fail.
231  *
232  * Return: GGTT's offset of the `Interrupt Status Report Page`_.
233  */
234 u32 xe_memirq_status_ptr(struct xe_memirq *memirq)
235 {
236 	memirq_assert(memirq, IS_SRIOV_VF(memirq_to_xe(memirq)));
237 	memirq_assert(memirq, xe_device_has_memirq(memirq_to_xe(memirq)));
238 	memirq_assert(memirq, memirq->bo);
239 
240 	return xe_bo_ggtt_addr(memirq->bo) + XE_MEMIRQ_STATUS_OFFSET;
241 }
242 
243 /**
244  * xe_memirq_enable_ptr - Get GGTT's offset of the Interrupt Enable Mask.
245  * @memirq: the &xe_memirq to query
246  *
247  * Shall be called only on VF driver when `Memory Based Interrupts`_ are used
248  * and xe_memirq_init() didn't fail.
249  *
250  * Return: GGTT's offset of the Interrupt Enable Mask.
251  */
252 u32 xe_memirq_enable_ptr(struct xe_memirq *memirq)
253 {
254 	memirq_assert(memirq, IS_SRIOV_VF(memirq_to_xe(memirq)));
255 	memirq_assert(memirq, xe_device_has_memirq(memirq_to_xe(memirq)));
256 	memirq_assert(memirq, memirq->bo);
257 
258 	return xe_bo_ggtt_addr(memirq->bo) + XE_MEMIRQ_ENABLE_OFFSET;
259 }
260 
261 /**
262  * xe_memirq_init_guc - Prepare GuC for `Memory Based Interrupts`_.
263  * @memirq: the &xe_memirq
264  * @guc: the &xe_guc to setup
265  *
266  * Register `Interrupt Source Report Page`_ and `Interrupt Status Report Page`_
267  * to be used by the GuC when `Memory Based Interrupts`_ are required.
268  *
269  * Shall be called only on VF driver when `Memory Based Interrupts`_ are used
270  * and xe_memirq_init() didn't fail.
271  *
272  * Return: 0 on success or a negative error code on failure.
273  */
274 int xe_memirq_init_guc(struct xe_memirq *memirq, struct xe_guc *guc)
275 {
276 	bool is_media = xe_gt_is_media_type(guc_to_gt(guc));
277 	u32 offset = is_media ? ilog2(INTR_MGUC) : ilog2(INTR_GUC);
278 	u32 source, status;
279 	int err;
280 
281 	memirq_assert(memirq, IS_SRIOV_VF(memirq_to_xe(memirq)));
282 	memirq_assert(memirq, xe_device_has_memirq(memirq_to_xe(memirq)));
283 	memirq_assert(memirq, memirq->bo);
284 
285 	source = xe_memirq_source_ptr(memirq) + offset;
286 	status = xe_memirq_status_ptr(memirq) + offset * SZ_16;
287 
288 	err = xe_guc_self_cfg64(guc, GUC_KLV_SELF_CFG_MEMIRQ_SOURCE_ADDR_KEY,
289 				source);
290 	if (unlikely(err))
291 		goto failed;
292 
293 	err = xe_guc_self_cfg64(guc, GUC_KLV_SELF_CFG_MEMIRQ_STATUS_ADDR_KEY,
294 				status);
295 	if (unlikely(err))
296 		goto failed;
297 
298 	return 0;
299 
300 failed:
301 	xe_sriov_err(memirq_to_xe(memirq),
302 		     "Failed to setup report pages in %s (%pe)\n",
303 		     guc_name(guc), ERR_PTR(err));
304 	return err;
305 }
306 
307 /**
308  * xe_memirq_reset - Disable processing of `Memory Based Interrupts`_.
309  * @memirq: struct xe_memirq
310  *
311  * This is part of the driver IRQ setup flow.
312  *
313  * This function shall only be used by the VF driver on platforms that use
314  * `Memory Based Interrupts`_.
315  */
316 void xe_memirq_reset(struct xe_memirq *memirq)
317 {
318 	memirq_assert(memirq, IS_SRIOV_VF(memirq_to_xe(memirq)));
319 	memirq_assert(memirq, xe_device_has_memirq(memirq_to_xe(memirq)));
320 
321 	if (memirq->bo)
322 		memirq_set_enable(memirq, false);
323 }
324 
325 /**
326  * xe_memirq_postinstall - Enable processing of `Memory Based Interrupts`_.
327  * @memirq: the &xe_memirq
328  *
329  * This is part of the driver IRQ setup flow.
330  *
331  * This function shall only be used by the VF driver on platforms that use
332  * `Memory Based Interrupts`_.
333  */
334 void xe_memirq_postinstall(struct xe_memirq *memirq)
335 {
336 	memirq_assert(memirq, IS_SRIOV_VF(memirq_to_xe(memirq)));
337 	memirq_assert(memirq, xe_device_has_memirq(memirq_to_xe(memirq)));
338 
339 	if (memirq->bo)
340 		memirq_set_enable(memirq, true);
341 }
342 
343 static bool memirq_received(struct xe_memirq *memirq, struct iosys_map *vector,
344 			    u16 offset, const char *name)
345 {
346 	u8 value;
347 
348 	value = iosys_map_rd(vector, offset, u8);
349 	if (value) {
350 		if (value != 0xff)
351 			xe_sriov_err_ratelimited(memirq_to_xe(memirq),
352 						 "Unexpected memirq value %#x from %s at %u\n",
353 						 value, name, offset);
354 		iosys_map_wr(vector, offset, u8, 0x00);
355 	}
356 
357 	return value;
358 }
359 
360 static void memirq_dispatch_engine(struct xe_memirq *memirq, struct iosys_map *status,
361 				   struct xe_hw_engine *hwe)
362 {
363 	memirq_debug(memirq, "STATUS %s %*ph\n", hwe->name, 16, status->vaddr);
364 
365 	if (memirq_received(memirq, status, ilog2(GT_RENDER_USER_INTERRUPT), hwe->name))
366 		xe_hw_engine_handle_irq(hwe, GT_RENDER_USER_INTERRUPT);
367 }
368 
369 static void memirq_dispatch_guc(struct xe_memirq *memirq, struct iosys_map *status,
370 				struct xe_guc *guc)
371 {
372 	const char *name = guc_name(guc);
373 
374 	memirq_debug(memirq, "STATUS %s %*ph\n", name, 16, status->vaddr);
375 
376 	if (memirq_received(memirq, status, ilog2(GUC_INTR_GUC2HOST), name))
377 		xe_guc_irq_handler(guc, GUC_INTR_GUC2HOST);
378 }
379 
380 /**
381  * xe_memirq_handler - The `Memory Based Interrupts`_ Handler.
382  * @memirq: the &xe_memirq
383  *
384  * This function reads and dispatches `Memory Based Interrupts`.
385  */
386 void xe_memirq_handler(struct xe_memirq *memirq)
387 {
388 	struct xe_device *xe = memirq_to_xe(memirq);
389 	struct xe_tile *tile = memirq_to_tile(memirq);
390 	struct xe_hw_engine *hwe;
391 	enum xe_hw_engine_id id;
392 	struct iosys_map map;
393 	unsigned int gtid;
394 	struct xe_gt *gt;
395 
396 	if (!memirq->bo)
397 		return;
398 
399 	memirq_assert(memirq, !memirq->source.is_iomem);
400 	memirq_debug(memirq, "SOURCE %*ph\n", 32, memirq->source.vaddr);
401 	memirq_debug(memirq, "SOURCE %*ph\n", 32, memirq->source.vaddr + 32);
402 
403 	for_each_gt(gt, xe, gtid) {
404 		if (gt->tile != tile)
405 			continue;
406 
407 		for_each_hw_engine(hwe, gt, id) {
408 			if (memirq_received(memirq, &memirq->source, hwe->irq_offset, "SRC")) {
409 				map = IOSYS_MAP_INIT_OFFSET(&memirq->status,
410 							    hwe->irq_offset * SZ_16);
411 				memirq_dispatch_engine(memirq, &map, hwe);
412 			}
413 		}
414 	}
415 
416 	/* GuC and media GuC (if present) must be checked separately */
417 
418 	if (memirq_received(memirq, &memirq->source, ilog2(INTR_GUC), "SRC")) {
419 		map = IOSYS_MAP_INIT_OFFSET(&memirq->status, ilog2(INTR_GUC) * SZ_16);
420 		memirq_dispatch_guc(memirq, &map, &tile->primary_gt->uc.guc);
421 	}
422 
423 	if (!tile->media_gt)
424 		return;
425 
426 	if (memirq_received(memirq, &memirq->source, ilog2(INTR_MGUC), "SRC")) {
427 		map = IOSYS_MAP_INIT_OFFSET(&memirq->status, ilog2(INTR_MGUC) * SZ_16);
428 		memirq_dispatch_guc(memirq, &map, &tile->media_gt->uc.guc);
429 	}
430 }
431