xref: /openbmc/linux/drivers/infiniband/hw/erdma/erdma_cmdq.c (revision 72769dba6dc0b8ac5793f94a83add4ce0108c44c)
1 // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
2 
3 /* Authors: Cheng Xu <chengyou@linux.alibaba.com> */
4 /*          Kai Shen <kaishen@linux.alibaba.com> */
5 /* Copyright (c) 2020-2022, Alibaba Group. */
6 
7 #include "erdma.h"
8 
9 static void arm_cmdq_cq(struct erdma_cmdq *cmdq)
10 {
11 	struct erdma_dev *dev = container_of(cmdq, struct erdma_dev, cmdq);
12 	u64 db_data = FIELD_PREP(ERDMA_CQDB_CI_MASK, cmdq->cq.ci) |
13 		      FIELD_PREP(ERDMA_CQDB_ARM_MASK, 1) |
14 		      FIELD_PREP(ERDMA_CQDB_CMDSN_MASK, cmdq->cq.cmdsn) |
15 		      FIELD_PREP(ERDMA_CQDB_IDX_MASK, cmdq->cq.cmdsn);
16 
17 	*cmdq->cq.db_record = db_data;
18 	writeq(db_data, dev->func_bar + ERDMA_CMDQ_CQDB_REG);
19 
20 	atomic64_inc(&cmdq->cq.armed_num);
21 }
22 
23 static void kick_cmdq_db(struct erdma_cmdq *cmdq)
24 {
25 	struct erdma_dev *dev = container_of(cmdq, struct erdma_dev, cmdq);
26 	u64 db_data = FIELD_PREP(ERDMA_CMD_HDR_WQEBB_INDEX_MASK, cmdq->sq.pi);
27 
28 	*cmdq->sq.db_record = db_data;
29 	writeq(db_data, dev->func_bar + ERDMA_CMDQ_SQDB_REG);
30 }
31 
32 static struct erdma_comp_wait *get_comp_wait(struct erdma_cmdq *cmdq)
33 {
34 	int comp_idx;
35 
36 	spin_lock(&cmdq->lock);
37 	comp_idx = find_first_zero_bit(cmdq->comp_wait_bitmap,
38 				       cmdq->max_outstandings);
39 	if (comp_idx == cmdq->max_outstandings) {
40 		spin_unlock(&cmdq->lock);
41 		return ERR_PTR(-ENOMEM);
42 	}
43 
44 	__set_bit(comp_idx, cmdq->comp_wait_bitmap);
45 	spin_unlock(&cmdq->lock);
46 
47 	return &cmdq->wait_pool[comp_idx];
48 }
49 
50 static void put_comp_wait(struct erdma_cmdq *cmdq,
51 			  struct erdma_comp_wait *comp_wait)
52 {
53 	int used;
54 
55 	cmdq->wait_pool[comp_wait->ctx_id].cmd_status = ERDMA_CMD_STATUS_INIT;
56 	spin_lock(&cmdq->lock);
57 	used = __test_and_clear_bit(comp_wait->ctx_id, cmdq->comp_wait_bitmap);
58 	spin_unlock(&cmdq->lock);
59 
60 	WARN_ON(!used);
61 }
62 
63 static int erdma_cmdq_wait_res_init(struct erdma_dev *dev,
64 				    struct erdma_cmdq *cmdq)
65 {
66 	int i;
67 
68 	cmdq->wait_pool =
69 		devm_kcalloc(&dev->pdev->dev, cmdq->max_outstandings,
70 			     sizeof(struct erdma_comp_wait), GFP_KERNEL);
71 	if (!cmdq->wait_pool)
72 		return -ENOMEM;
73 
74 	spin_lock_init(&cmdq->lock);
75 	cmdq->comp_wait_bitmap = devm_bitmap_zalloc(
76 		&dev->pdev->dev, cmdq->max_outstandings, GFP_KERNEL);
77 	if (!cmdq->comp_wait_bitmap)
78 		return -ENOMEM;
79 
80 	for (i = 0; i < cmdq->max_outstandings; i++) {
81 		init_completion(&cmdq->wait_pool[i].wait_event);
82 		cmdq->wait_pool[i].ctx_id = i;
83 	}
84 
85 	return 0;
86 }
87 
88 static int erdma_cmdq_sq_init(struct erdma_dev *dev)
89 {
90 	struct erdma_cmdq *cmdq = &dev->cmdq;
91 	struct erdma_cmdq_sq *sq = &cmdq->sq;
92 	u32 buf_size;
93 
94 	sq->wqebb_cnt = SQEBB_COUNT(ERDMA_CMDQ_SQE_SIZE);
95 	sq->depth = cmdq->max_outstandings * sq->wqebb_cnt;
96 
97 	buf_size = sq->depth << SQEBB_SHIFT;
98 
99 	sq->qbuf =
100 		dma_alloc_coherent(&dev->pdev->dev, WARPPED_BUFSIZE(buf_size),
101 				   &sq->qbuf_dma_addr, GFP_KERNEL);
102 	if (!sq->qbuf)
103 		return -ENOMEM;
104 
105 	sq->db_record = (u64 *)(sq->qbuf + buf_size);
106 
107 	spin_lock_init(&sq->lock);
108 
109 	erdma_reg_write32(dev, ERDMA_REGS_CMDQ_SQ_ADDR_H_REG,
110 			  upper_32_bits(sq->qbuf_dma_addr));
111 	erdma_reg_write32(dev, ERDMA_REGS_CMDQ_SQ_ADDR_L_REG,
112 			  lower_32_bits(sq->qbuf_dma_addr));
113 	erdma_reg_write32(dev, ERDMA_REGS_CMDQ_DEPTH_REG, sq->depth);
114 	erdma_reg_write64(dev, ERDMA_CMDQ_SQ_DB_HOST_ADDR_REG,
115 			  sq->qbuf_dma_addr + buf_size);
116 
117 	return 0;
118 }
119 
120 static int erdma_cmdq_cq_init(struct erdma_dev *dev)
121 {
122 	struct erdma_cmdq *cmdq = &dev->cmdq;
123 	struct erdma_cmdq_cq *cq = &cmdq->cq;
124 	u32 buf_size;
125 
126 	cq->depth = cmdq->sq.depth;
127 	buf_size = cq->depth << CQE_SHIFT;
128 
129 	cq->qbuf =
130 		dma_alloc_coherent(&dev->pdev->dev, WARPPED_BUFSIZE(buf_size),
131 				   &cq->qbuf_dma_addr, GFP_KERNEL | __GFP_ZERO);
132 	if (!cq->qbuf)
133 		return -ENOMEM;
134 
135 	spin_lock_init(&cq->lock);
136 
137 	cq->db_record = (u64 *)(cq->qbuf + buf_size);
138 
139 	atomic64_set(&cq->armed_num, 0);
140 
141 	erdma_reg_write32(dev, ERDMA_REGS_CMDQ_CQ_ADDR_H_REG,
142 			  upper_32_bits(cq->qbuf_dma_addr));
143 	erdma_reg_write32(dev, ERDMA_REGS_CMDQ_CQ_ADDR_L_REG,
144 			  lower_32_bits(cq->qbuf_dma_addr));
145 	erdma_reg_write64(dev, ERDMA_CMDQ_CQ_DB_HOST_ADDR_REG,
146 			  cq->qbuf_dma_addr + buf_size);
147 
148 	return 0;
149 }
150 
151 static int erdma_cmdq_eq_init(struct erdma_dev *dev)
152 {
153 	struct erdma_cmdq *cmdq = &dev->cmdq;
154 	struct erdma_eq *eq = &cmdq->eq;
155 	u32 buf_size;
156 
157 	eq->depth = cmdq->max_outstandings;
158 	buf_size = eq->depth << EQE_SHIFT;
159 
160 	eq->qbuf =
161 		dma_alloc_coherent(&dev->pdev->dev, WARPPED_BUFSIZE(buf_size),
162 				   &eq->qbuf_dma_addr, GFP_KERNEL | __GFP_ZERO);
163 	if (!eq->qbuf)
164 		return -ENOMEM;
165 
166 	spin_lock_init(&eq->lock);
167 	atomic64_set(&eq->event_num, 0);
168 
169 	eq->db = dev->func_bar + ERDMA_REGS_CEQ_DB_BASE_REG;
170 	eq->db_record = (u64 *)(eq->qbuf + buf_size);
171 
172 	erdma_reg_write32(dev, ERDMA_REGS_CMDQ_EQ_ADDR_H_REG,
173 			  upper_32_bits(eq->qbuf_dma_addr));
174 	erdma_reg_write32(dev, ERDMA_REGS_CMDQ_EQ_ADDR_L_REG,
175 			  lower_32_bits(eq->qbuf_dma_addr));
176 	erdma_reg_write32(dev, ERDMA_REGS_CMDQ_EQ_DEPTH_REG, eq->depth);
177 	erdma_reg_write64(dev, ERDMA_CMDQ_EQ_DB_HOST_ADDR_REG,
178 			  eq->qbuf_dma_addr + buf_size);
179 
180 	return 0;
181 }
182 
183 int erdma_cmdq_init(struct erdma_dev *dev)
184 {
185 	int err, i;
186 	struct erdma_cmdq *cmdq = &dev->cmdq;
187 	u32 sts, ctrl;
188 
189 	cmdq->max_outstandings = ERDMA_CMDQ_MAX_OUTSTANDING;
190 	cmdq->use_event = false;
191 
192 	sema_init(&cmdq->credits, cmdq->max_outstandings);
193 
194 	err = erdma_cmdq_wait_res_init(dev, cmdq);
195 	if (err)
196 		return err;
197 
198 	err = erdma_cmdq_sq_init(dev);
199 	if (err)
200 		return err;
201 
202 	err = erdma_cmdq_cq_init(dev);
203 	if (err)
204 		goto err_destroy_sq;
205 
206 	err = erdma_cmdq_eq_init(dev);
207 	if (err)
208 		goto err_destroy_cq;
209 
210 	ctrl = FIELD_PREP(ERDMA_REG_DEV_CTRL_INIT_MASK, 1);
211 	erdma_reg_write32(dev, ERDMA_REGS_DEV_CTRL_REG, ctrl);
212 
213 	for (i = 0; i < ERDMA_WAIT_DEV_DONE_CNT; i++) {
214 		sts = erdma_reg_read32_filed(dev, ERDMA_REGS_DEV_ST_REG,
215 					     ERDMA_REG_DEV_ST_INIT_DONE_MASK);
216 		if (sts)
217 			break;
218 
219 		msleep(ERDMA_REG_ACCESS_WAIT_MS);
220 	}
221 
222 	if (i == ERDMA_WAIT_DEV_DONE_CNT) {
223 		dev_err(&dev->pdev->dev, "wait init done failed.\n");
224 		err = -ETIMEDOUT;
225 		goto err_destroy_eq;
226 	}
227 
228 	set_bit(ERDMA_CMDQ_STATE_OK_BIT, &cmdq->state);
229 
230 	return 0;
231 
232 err_destroy_eq:
233 	dma_free_coherent(&dev->pdev->dev,
234 			  (cmdq->eq.depth << EQE_SHIFT) +
235 				  ERDMA_EXTRA_BUFFER_SIZE,
236 			  cmdq->eq.qbuf, cmdq->eq.qbuf_dma_addr);
237 
238 err_destroy_cq:
239 	dma_free_coherent(&dev->pdev->dev,
240 			  (cmdq->cq.depth << CQE_SHIFT) +
241 				  ERDMA_EXTRA_BUFFER_SIZE,
242 			  cmdq->cq.qbuf, cmdq->cq.qbuf_dma_addr);
243 
244 err_destroy_sq:
245 	dma_free_coherent(&dev->pdev->dev,
246 			  (cmdq->sq.depth << SQEBB_SHIFT) +
247 				  ERDMA_EXTRA_BUFFER_SIZE,
248 			  cmdq->sq.qbuf, cmdq->sq.qbuf_dma_addr);
249 
250 	return err;
251 }
252 
253 void erdma_finish_cmdq_init(struct erdma_dev *dev)
254 {
255 	/* after device init successfully, change cmdq to event mode. */
256 	dev->cmdq.use_event = true;
257 	arm_cmdq_cq(&dev->cmdq);
258 }
259 
260 void erdma_cmdq_destroy(struct erdma_dev *dev)
261 {
262 	struct erdma_cmdq *cmdq = &dev->cmdq;
263 
264 	clear_bit(ERDMA_CMDQ_STATE_OK_BIT, &cmdq->state);
265 
266 	dma_free_coherent(&dev->pdev->dev,
267 			  (cmdq->eq.depth << EQE_SHIFT) +
268 				  ERDMA_EXTRA_BUFFER_SIZE,
269 			  cmdq->eq.qbuf, cmdq->eq.qbuf_dma_addr);
270 	dma_free_coherent(&dev->pdev->dev,
271 			  (cmdq->sq.depth << SQEBB_SHIFT) +
272 				  ERDMA_EXTRA_BUFFER_SIZE,
273 			  cmdq->sq.qbuf, cmdq->sq.qbuf_dma_addr);
274 	dma_free_coherent(&dev->pdev->dev,
275 			  (cmdq->cq.depth << CQE_SHIFT) +
276 				  ERDMA_EXTRA_BUFFER_SIZE,
277 			  cmdq->cq.qbuf, cmdq->cq.qbuf_dma_addr);
278 }
279 
280 static void *get_next_valid_cmdq_cqe(struct erdma_cmdq *cmdq)
281 {
282 	__be32 *cqe = get_queue_entry(cmdq->cq.qbuf, cmdq->cq.ci,
283 				      cmdq->cq.depth, CQE_SHIFT);
284 	u32 owner = FIELD_GET(ERDMA_CQE_HDR_OWNER_MASK,
285 			      be32_to_cpu(READ_ONCE(*cqe)));
286 
287 	return owner ^ !!(cmdq->cq.ci & cmdq->cq.depth) ? cqe : NULL;
288 }
289 
290 static void push_cmdq_sqe(struct erdma_cmdq *cmdq, u64 *req, size_t req_len,
291 			  struct erdma_comp_wait *comp_wait)
292 {
293 	__le64 *wqe;
294 	u64 hdr = *req;
295 
296 	comp_wait->cmd_status = ERDMA_CMD_STATUS_ISSUED;
297 	reinit_completion(&comp_wait->wait_event);
298 	comp_wait->sq_pi = cmdq->sq.pi;
299 
300 	wqe = get_queue_entry(cmdq->sq.qbuf, cmdq->sq.pi, cmdq->sq.depth,
301 			      SQEBB_SHIFT);
302 	memcpy(wqe, req, req_len);
303 
304 	cmdq->sq.pi += cmdq->sq.wqebb_cnt;
305 	hdr |= FIELD_PREP(ERDMA_CMD_HDR_WQEBB_INDEX_MASK, cmdq->sq.pi) |
306 	       FIELD_PREP(ERDMA_CMD_HDR_CONTEXT_COOKIE_MASK,
307 			  comp_wait->ctx_id) |
308 	       FIELD_PREP(ERDMA_CMD_HDR_WQEBB_CNT_MASK, cmdq->sq.wqebb_cnt - 1);
309 	*wqe = cpu_to_le64(hdr);
310 
311 	kick_cmdq_db(cmdq);
312 }
313 
314 static int erdma_poll_single_cmd_completion(struct erdma_cmdq *cmdq)
315 {
316 	struct erdma_comp_wait *comp_wait;
317 	u32 hdr0, sqe_idx;
318 	__be32 *cqe;
319 	u16 ctx_id;
320 	u64 *sqe;
321 
322 	cqe = get_next_valid_cmdq_cqe(cmdq);
323 	if (!cqe)
324 		return -EAGAIN;
325 
326 	cmdq->cq.ci++;
327 
328 	dma_rmb();
329 	hdr0 = be32_to_cpu(*cqe);
330 	sqe_idx = be32_to_cpu(*(cqe + 1));
331 
332 	sqe = get_queue_entry(cmdq->sq.qbuf, sqe_idx, cmdq->sq.depth,
333 			      SQEBB_SHIFT);
334 	ctx_id = FIELD_GET(ERDMA_CMD_HDR_CONTEXT_COOKIE_MASK, *sqe);
335 	comp_wait = &cmdq->wait_pool[ctx_id];
336 	if (comp_wait->cmd_status != ERDMA_CMD_STATUS_ISSUED)
337 		return -EIO;
338 
339 	comp_wait->cmd_status = ERDMA_CMD_STATUS_FINISHED;
340 	comp_wait->comp_status = FIELD_GET(ERDMA_CQE_HDR_SYNDROME_MASK, hdr0);
341 	cmdq->sq.ci += cmdq->sq.wqebb_cnt;
342 	/* Copy 16B comp data after cqe hdr to outer */
343 	be32_to_cpu_array(comp_wait->comp_data, cqe + 2, 4);
344 
345 	if (cmdq->use_event)
346 		complete(&comp_wait->wait_event);
347 
348 	return 0;
349 }
350 
351 static void erdma_polling_cmd_completions(struct erdma_cmdq *cmdq)
352 {
353 	unsigned long flags;
354 	u16 comp_num;
355 
356 	spin_lock_irqsave(&cmdq->cq.lock, flags);
357 
358 	/* We must have less than # of max_outstandings
359 	 * completions at one time.
360 	 */
361 	for (comp_num = 0; comp_num < cmdq->max_outstandings; comp_num++)
362 		if (erdma_poll_single_cmd_completion(cmdq))
363 			break;
364 
365 	if (comp_num && cmdq->use_event)
366 		arm_cmdq_cq(cmdq);
367 
368 	spin_unlock_irqrestore(&cmdq->cq.lock, flags);
369 }
370 
371 void erdma_cmdq_completion_handler(struct erdma_cmdq *cmdq)
372 {
373 	int got_event = 0;
374 
375 	if (!test_bit(ERDMA_CMDQ_STATE_OK_BIT, &cmdq->state) ||
376 	    !cmdq->use_event)
377 		return;
378 
379 	while (get_next_valid_eqe(&cmdq->eq)) {
380 		cmdq->eq.ci++;
381 		got_event++;
382 	}
383 
384 	if (got_event) {
385 		cmdq->cq.cmdsn++;
386 		erdma_polling_cmd_completions(cmdq);
387 	}
388 
389 	notify_eq(&cmdq->eq);
390 }
391 
392 static int erdma_poll_cmd_completion(struct erdma_comp_wait *comp_ctx,
393 				     struct erdma_cmdq *cmdq, u32 timeout)
394 {
395 	unsigned long comp_timeout = jiffies + msecs_to_jiffies(timeout);
396 
397 	while (1) {
398 		erdma_polling_cmd_completions(cmdq);
399 		if (comp_ctx->cmd_status != ERDMA_CMD_STATUS_ISSUED)
400 			break;
401 
402 		if (time_is_before_jiffies(comp_timeout))
403 			return -ETIME;
404 
405 		msleep(20);
406 	}
407 
408 	return 0;
409 }
410 
411 static int erdma_wait_cmd_completion(struct erdma_comp_wait *comp_ctx,
412 				     struct erdma_cmdq *cmdq, u32 timeout)
413 {
414 	unsigned long flags = 0;
415 
416 	wait_for_completion_timeout(&comp_ctx->wait_event,
417 				    msecs_to_jiffies(timeout));
418 
419 	if (unlikely(comp_ctx->cmd_status != ERDMA_CMD_STATUS_FINISHED)) {
420 		spin_lock_irqsave(&cmdq->cq.lock, flags);
421 		comp_ctx->cmd_status = ERDMA_CMD_STATUS_TIMEOUT;
422 		spin_unlock_irqrestore(&cmdq->cq.lock, flags);
423 		return -ETIME;
424 	}
425 
426 	return 0;
427 }
428 
429 void erdma_cmdq_build_reqhdr(u64 *hdr, u32 mod, u32 op)
430 {
431 	*hdr = FIELD_PREP(ERDMA_CMD_HDR_SUB_MOD_MASK, mod) |
432 	       FIELD_PREP(ERDMA_CMD_HDR_OPCODE_MASK, op);
433 }
434 
435 int erdma_post_cmd_wait(struct erdma_cmdq *cmdq, void *req, u32 req_size,
436 			u64 *resp0, u64 *resp1)
437 {
438 	struct erdma_comp_wait *comp_wait;
439 	int ret;
440 
441 	if (!test_bit(ERDMA_CMDQ_STATE_OK_BIT, &cmdq->state))
442 		return -ENODEV;
443 
444 	down(&cmdq->credits);
445 
446 	comp_wait = get_comp_wait(cmdq);
447 	if (IS_ERR(comp_wait)) {
448 		clear_bit(ERDMA_CMDQ_STATE_OK_BIT, &cmdq->state);
449 		set_bit(ERDMA_CMDQ_STATE_CTX_ERR_BIT, &cmdq->state);
450 		up(&cmdq->credits);
451 		return PTR_ERR(comp_wait);
452 	}
453 
454 	spin_lock(&cmdq->sq.lock);
455 	push_cmdq_sqe(cmdq, req, req_size, comp_wait);
456 	spin_unlock(&cmdq->sq.lock);
457 
458 	if (cmdq->use_event)
459 		ret = erdma_wait_cmd_completion(comp_wait, cmdq,
460 						ERDMA_CMDQ_TIMEOUT_MS);
461 	else
462 		ret = erdma_poll_cmd_completion(comp_wait, cmdq,
463 						ERDMA_CMDQ_TIMEOUT_MS);
464 
465 	if (ret) {
466 		set_bit(ERDMA_CMDQ_STATE_TIMEOUT_BIT, &cmdq->state);
467 		clear_bit(ERDMA_CMDQ_STATE_OK_BIT, &cmdq->state);
468 		goto out;
469 	}
470 
471 	if (comp_wait->comp_status)
472 		ret = -EIO;
473 
474 	if (resp0 && resp1) {
475 		*resp0 = *((u64 *)&comp_wait->comp_data[0]);
476 		*resp1 = *((u64 *)&comp_wait->comp_data[2]);
477 	}
478 	put_comp_wait(cmdq, comp_wait);
479 
480 out:
481 	up(&cmdq->credits);
482 
483 	return ret;
484 }
485