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 	struct erdma_cmdq *cmdq = &dev->cmdq;
186 	int err;
187 
188 	cmdq->max_outstandings = ERDMA_CMDQ_MAX_OUTSTANDING;
189 	cmdq->use_event = false;
190 
191 	sema_init(&cmdq->credits, cmdq->max_outstandings);
192 
193 	err = erdma_cmdq_wait_res_init(dev, cmdq);
194 	if (err)
195 		return err;
196 
197 	err = erdma_cmdq_sq_init(dev);
198 	if (err)
199 		return err;
200 
201 	err = erdma_cmdq_cq_init(dev);
202 	if (err)
203 		goto err_destroy_sq;
204 
205 	err = erdma_cmdq_eq_init(dev);
206 	if (err)
207 		goto err_destroy_cq;
208 
209 	set_bit(ERDMA_CMDQ_STATE_OK_BIT, &cmdq->state);
210 
211 	return 0;
212 
213 err_destroy_cq:
214 	dma_free_coherent(&dev->pdev->dev,
215 			  (cmdq->cq.depth << CQE_SHIFT) +
216 				  ERDMA_EXTRA_BUFFER_SIZE,
217 			  cmdq->cq.qbuf, cmdq->cq.qbuf_dma_addr);
218 
219 err_destroy_sq:
220 	dma_free_coherent(&dev->pdev->dev,
221 			  (cmdq->sq.depth << SQEBB_SHIFT) +
222 				  ERDMA_EXTRA_BUFFER_SIZE,
223 			  cmdq->sq.qbuf, cmdq->sq.qbuf_dma_addr);
224 
225 	return err;
226 }
227 
228 void erdma_finish_cmdq_init(struct erdma_dev *dev)
229 {
230 	/* after device init successfully, change cmdq to event mode. */
231 	dev->cmdq.use_event = true;
232 	arm_cmdq_cq(&dev->cmdq);
233 }
234 
235 void erdma_cmdq_destroy(struct erdma_dev *dev)
236 {
237 	struct erdma_cmdq *cmdq = &dev->cmdq;
238 
239 	clear_bit(ERDMA_CMDQ_STATE_OK_BIT, &cmdq->state);
240 
241 	dma_free_coherent(&dev->pdev->dev,
242 			  (cmdq->eq.depth << EQE_SHIFT) +
243 				  ERDMA_EXTRA_BUFFER_SIZE,
244 			  cmdq->eq.qbuf, cmdq->eq.qbuf_dma_addr);
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 	dma_free_coherent(&dev->pdev->dev,
250 			  (cmdq->cq.depth << CQE_SHIFT) +
251 				  ERDMA_EXTRA_BUFFER_SIZE,
252 			  cmdq->cq.qbuf, cmdq->cq.qbuf_dma_addr);
253 }
254 
255 static void *get_next_valid_cmdq_cqe(struct erdma_cmdq *cmdq)
256 {
257 	__be32 *cqe = get_queue_entry(cmdq->cq.qbuf, cmdq->cq.ci,
258 				      cmdq->cq.depth, CQE_SHIFT);
259 	u32 owner = FIELD_GET(ERDMA_CQE_HDR_OWNER_MASK,
260 			      be32_to_cpu(READ_ONCE(*cqe)));
261 
262 	return owner ^ !!(cmdq->cq.ci & cmdq->cq.depth) ? cqe : NULL;
263 }
264 
265 static void push_cmdq_sqe(struct erdma_cmdq *cmdq, u64 *req, size_t req_len,
266 			  struct erdma_comp_wait *comp_wait)
267 {
268 	__le64 *wqe;
269 	u64 hdr = *req;
270 
271 	comp_wait->cmd_status = ERDMA_CMD_STATUS_ISSUED;
272 	reinit_completion(&comp_wait->wait_event);
273 	comp_wait->sq_pi = cmdq->sq.pi;
274 
275 	wqe = get_queue_entry(cmdq->sq.qbuf, cmdq->sq.pi, cmdq->sq.depth,
276 			      SQEBB_SHIFT);
277 	memcpy(wqe, req, req_len);
278 
279 	cmdq->sq.pi += cmdq->sq.wqebb_cnt;
280 	hdr |= FIELD_PREP(ERDMA_CMD_HDR_WQEBB_INDEX_MASK, cmdq->sq.pi) |
281 	       FIELD_PREP(ERDMA_CMD_HDR_CONTEXT_COOKIE_MASK,
282 			  comp_wait->ctx_id) |
283 	       FIELD_PREP(ERDMA_CMD_HDR_WQEBB_CNT_MASK, cmdq->sq.wqebb_cnt - 1);
284 	*wqe = cpu_to_le64(hdr);
285 
286 	kick_cmdq_db(cmdq);
287 }
288 
289 static int erdma_poll_single_cmd_completion(struct erdma_cmdq *cmdq)
290 {
291 	struct erdma_comp_wait *comp_wait;
292 	u32 hdr0, sqe_idx;
293 	__be32 *cqe;
294 	u16 ctx_id;
295 	u64 *sqe;
296 
297 	cqe = get_next_valid_cmdq_cqe(cmdq);
298 	if (!cqe)
299 		return -EAGAIN;
300 
301 	cmdq->cq.ci++;
302 
303 	dma_rmb();
304 	hdr0 = be32_to_cpu(*cqe);
305 	sqe_idx = be32_to_cpu(*(cqe + 1));
306 
307 	sqe = get_queue_entry(cmdq->sq.qbuf, sqe_idx, cmdq->sq.depth,
308 			      SQEBB_SHIFT);
309 	ctx_id = FIELD_GET(ERDMA_CMD_HDR_CONTEXT_COOKIE_MASK, *sqe);
310 	comp_wait = &cmdq->wait_pool[ctx_id];
311 	if (comp_wait->cmd_status != ERDMA_CMD_STATUS_ISSUED)
312 		return -EIO;
313 
314 	comp_wait->cmd_status = ERDMA_CMD_STATUS_FINISHED;
315 	comp_wait->comp_status = FIELD_GET(ERDMA_CQE_HDR_SYNDROME_MASK, hdr0);
316 	cmdq->sq.ci += cmdq->sq.wqebb_cnt;
317 	/* Copy 16B comp data after cqe hdr to outer */
318 	be32_to_cpu_array(comp_wait->comp_data, cqe + 2, 4);
319 
320 	if (cmdq->use_event)
321 		complete(&comp_wait->wait_event);
322 
323 	return 0;
324 }
325 
326 static void erdma_polling_cmd_completions(struct erdma_cmdq *cmdq)
327 {
328 	unsigned long flags;
329 	u16 comp_num;
330 
331 	spin_lock_irqsave(&cmdq->cq.lock, flags);
332 
333 	/* We must have less than # of max_outstandings
334 	 * completions at one time.
335 	 */
336 	for (comp_num = 0; comp_num < cmdq->max_outstandings; comp_num++)
337 		if (erdma_poll_single_cmd_completion(cmdq))
338 			break;
339 
340 	if (comp_num && cmdq->use_event)
341 		arm_cmdq_cq(cmdq);
342 
343 	spin_unlock_irqrestore(&cmdq->cq.lock, flags);
344 }
345 
346 void erdma_cmdq_completion_handler(struct erdma_cmdq *cmdq)
347 {
348 	int got_event = 0;
349 
350 	if (!test_bit(ERDMA_CMDQ_STATE_OK_BIT, &cmdq->state) ||
351 	    !cmdq->use_event)
352 		return;
353 
354 	while (get_next_valid_eqe(&cmdq->eq)) {
355 		cmdq->eq.ci++;
356 		got_event++;
357 	}
358 
359 	if (got_event) {
360 		cmdq->cq.cmdsn++;
361 		erdma_polling_cmd_completions(cmdq);
362 	}
363 
364 	notify_eq(&cmdq->eq);
365 }
366 
367 static int erdma_poll_cmd_completion(struct erdma_comp_wait *comp_ctx,
368 				     struct erdma_cmdq *cmdq, u32 timeout)
369 {
370 	unsigned long comp_timeout = jiffies + msecs_to_jiffies(timeout);
371 
372 	while (1) {
373 		erdma_polling_cmd_completions(cmdq);
374 		if (comp_ctx->cmd_status != ERDMA_CMD_STATUS_ISSUED)
375 			break;
376 
377 		if (time_is_before_jiffies(comp_timeout))
378 			return -ETIME;
379 
380 		msleep(20);
381 	}
382 
383 	return 0;
384 }
385 
386 static int erdma_wait_cmd_completion(struct erdma_comp_wait *comp_ctx,
387 				     struct erdma_cmdq *cmdq, u32 timeout)
388 {
389 	unsigned long flags = 0;
390 
391 	wait_for_completion_timeout(&comp_ctx->wait_event,
392 				    msecs_to_jiffies(timeout));
393 
394 	if (unlikely(comp_ctx->cmd_status != ERDMA_CMD_STATUS_FINISHED)) {
395 		spin_lock_irqsave(&cmdq->cq.lock, flags);
396 		comp_ctx->cmd_status = ERDMA_CMD_STATUS_TIMEOUT;
397 		spin_unlock_irqrestore(&cmdq->cq.lock, flags);
398 		return -ETIME;
399 	}
400 
401 	return 0;
402 }
403 
404 void erdma_cmdq_build_reqhdr(u64 *hdr, u32 mod, u32 op)
405 {
406 	*hdr = FIELD_PREP(ERDMA_CMD_HDR_SUB_MOD_MASK, mod) |
407 	       FIELD_PREP(ERDMA_CMD_HDR_OPCODE_MASK, op);
408 }
409 
410 int erdma_post_cmd_wait(struct erdma_cmdq *cmdq, void *req, u32 req_size,
411 			u64 *resp0, u64 *resp1)
412 {
413 	struct erdma_comp_wait *comp_wait;
414 	int ret;
415 
416 	if (!test_bit(ERDMA_CMDQ_STATE_OK_BIT, &cmdq->state))
417 		return -ENODEV;
418 
419 	down(&cmdq->credits);
420 
421 	comp_wait = get_comp_wait(cmdq);
422 	if (IS_ERR(comp_wait)) {
423 		clear_bit(ERDMA_CMDQ_STATE_OK_BIT, &cmdq->state);
424 		set_bit(ERDMA_CMDQ_STATE_CTX_ERR_BIT, &cmdq->state);
425 		up(&cmdq->credits);
426 		return PTR_ERR(comp_wait);
427 	}
428 
429 	spin_lock(&cmdq->sq.lock);
430 	push_cmdq_sqe(cmdq, req, req_size, comp_wait);
431 	spin_unlock(&cmdq->sq.lock);
432 
433 	if (cmdq->use_event)
434 		ret = erdma_wait_cmd_completion(comp_wait, cmdq,
435 						ERDMA_CMDQ_TIMEOUT_MS);
436 	else
437 		ret = erdma_poll_cmd_completion(comp_wait, cmdq,
438 						ERDMA_CMDQ_TIMEOUT_MS);
439 
440 	if (ret) {
441 		set_bit(ERDMA_CMDQ_STATE_TIMEOUT_BIT, &cmdq->state);
442 		clear_bit(ERDMA_CMDQ_STATE_OK_BIT, &cmdq->state);
443 		goto out;
444 	}
445 
446 	if (comp_wait->comp_status)
447 		ret = -EIO;
448 
449 	if (resp0 && resp1) {
450 		*resp0 = *((u64 *)&comp_wait->comp_data[0]);
451 		*resp1 = *((u64 *)&comp_wait->comp_data[2]);
452 	}
453 	put_comp_wait(cmdq, comp_wait);
454 
455 out:
456 	up(&cmdq->credits);
457 
458 	return ret;
459 }
460