xref: /linux/drivers/crypto/cavium/nitrox/nitrox_reqmgr.c (revision 76d09ea7c22f2cabf1f66ffc287c23b19b120be9)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/gfp.h>
3 #include <linux/workqueue.h>
4 #include <crypto/internal/skcipher.h>
5 
6 #include "nitrox_dev.h"
7 #include "nitrox_req.h"
8 #include "nitrox_csr.h"
9 
10 /* SLC_STORE_INFO */
11 #define MIN_UDD_LEN 16
12 /* PKT_IN_HDR + SLC_STORE_INFO */
13 #define FDATA_SIZE 32
14 /* Base destination port for the solicited requests */
15 #define SOLICIT_BASE_DPORT 256
16 
17 #define REQ_NOT_POSTED 1
18 #define REQ_BACKLOG    2
19 #define REQ_POSTED     3
20 
21 /**
22  * Response codes from SE microcode
23  * 0x00 - Success
24  *   Completion with no error
25  * 0x43 - ERR_GC_DATA_LEN_INVALID
26  *   Invalid Data length if Encryption Data length is
27  *   less than 16 bytes for AES-XTS and AES-CTS.
28  * 0x45 - ERR_GC_CTX_LEN_INVALID
29  *   Invalid context length: CTXL != 23 words.
30  * 0x4F - ERR_GC_DOCSIS_CIPHER_INVALID
31  *   DOCSIS support is enabled with other than
32  *   AES/DES-CBC mode encryption.
33  * 0x50 - ERR_GC_DOCSIS_OFFSET_INVALID
34  *   Authentication offset is other than 0 with
35  *   Encryption IV source = 0.
36  *   Authentication offset is other than 8 (DES)/16 (AES)
37  *   with Encryption IV source = 1
38  * 0x51 - ERR_GC_CRC32_INVALID_SELECTION
39  *   CRC32 is enabled for other than DOCSIS encryption.
40  * 0x52 - ERR_GC_AES_CCM_FLAG_INVALID
41  *   Invalid flag options in AES-CCM IV.
42  */
43 
44 static inline int incr_index(int index, int count, int max)
45 {
46 	if ((index + count) >= max)
47 		index = index + count - max;
48 	else
49 		index += count;
50 
51 	return index;
52 }
53 
54 static void softreq_unmap_sgbufs(struct nitrox_softreq *sr)
55 {
56 	struct nitrox_device *ndev = sr->ndev;
57 	struct device *dev = DEV(ndev);
58 
59 
60 	dma_unmap_sg(dev, sr->in.sg, sr->in.sgmap_cnt, DMA_BIDIRECTIONAL);
61 	dma_unmap_single(dev, sr->in.sgcomp_dma, sr->in.sgcomp_len,
62 			 DMA_TO_DEVICE);
63 	kfree(sr->in.sgcomp);
64 	sr->in.sg = NULL;
65 	sr->in.sgmap_cnt = 0;
66 
67 	dma_unmap_sg(dev, sr->out.sg, sr->out.sgmap_cnt,
68 		     DMA_BIDIRECTIONAL);
69 	dma_unmap_single(dev, sr->out.sgcomp_dma, sr->out.sgcomp_len,
70 			 DMA_TO_DEVICE);
71 	kfree(sr->out.sgcomp);
72 	sr->out.sg = NULL;
73 	sr->out.sgmap_cnt = 0;
74 }
75 
76 static void softreq_destroy(struct nitrox_softreq *sr)
77 {
78 	softreq_unmap_sgbufs(sr);
79 	kfree(sr);
80 }
81 
82 /**
83  * create_sg_component - create SG componets for N5 device.
84  * @sr: Request structure
85  * @sgtbl: SG table
86  * @map_nents: number of dma mapped entries
87  *
88  * Component structure
89  *
90  *   63     48 47     32 31    16 15      0
91  *   --------------------------------------
92  *   |   LEN0  |  LEN1  |  LEN2  |  LEN3  |
93  *   |-------------------------------------
94  *   |               PTR0                 |
95  *   --------------------------------------
96  *   |               PTR1                 |
97  *   --------------------------------------
98  *   |               PTR2                 |
99  *   --------------------------------------
100  *   |               PTR3                 |
101  *   --------------------------------------
102  *
103  *   Returns 0 if success or a negative errno code on error.
104  */
105 static int create_sg_component(struct nitrox_softreq *sr,
106 			       struct nitrox_sgtable *sgtbl, int map_nents)
107 {
108 	struct nitrox_device *ndev = sr->ndev;
109 	struct nitrox_sgcomp *sgcomp;
110 	struct scatterlist *sg;
111 	dma_addr_t dma;
112 	size_t sz_comp;
113 	int i, j, nr_sgcomp;
114 
115 	nr_sgcomp = roundup(map_nents, 4) / 4;
116 
117 	/* each component holds 4 dma pointers */
118 	sz_comp = nr_sgcomp * sizeof(*sgcomp);
119 	sgcomp = kzalloc(sz_comp, sr->gfp);
120 	if (!sgcomp)
121 		return -ENOMEM;
122 
123 	sgtbl->sgcomp = sgcomp;
124 
125 	sg = sgtbl->sg;
126 	/* populate device sg component */
127 	for (i = 0; i < nr_sgcomp; i++) {
128 		for (j = 0; j < 4 && sg; j++) {
129 			sgcomp[i].len[j] = cpu_to_be16(sg_dma_len(sg));
130 			sgcomp[i].dma[j] = cpu_to_be64(sg_dma_address(sg));
131 			sg = sg_next(sg);
132 		}
133 	}
134 	/* map the device sg component */
135 	dma = dma_map_single(DEV(ndev), sgtbl->sgcomp, sz_comp, DMA_TO_DEVICE);
136 	if (dma_mapping_error(DEV(ndev), dma)) {
137 		kfree(sgtbl->sgcomp);
138 		sgtbl->sgcomp = NULL;
139 		return -ENOMEM;
140 	}
141 
142 	sgtbl->sgcomp_dma = dma;
143 	sgtbl->sgcomp_len = sz_comp;
144 
145 	return 0;
146 }
147 
148 /**
149  * dma_map_inbufs - DMA map input sglist and creates sglist component
150  *                  for N5 device.
151  * @sr: Request structure
152  * @req: Crypto request structre
153  *
154  * Returns 0 if successful or a negative errno code on error.
155  */
156 static int dma_map_inbufs(struct nitrox_softreq *sr,
157 			  struct se_crypto_request *req)
158 {
159 	struct device *dev = DEV(sr->ndev);
160 	struct scatterlist *sg = req->src;
161 	int i, nents, ret = 0;
162 
163 	nents = dma_map_sg(dev, req->src, sg_nents(req->src),
164 			   DMA_BIDIRECTIONAL);
165 	if (!nents)
166 		return -EINVAL;
167 
168 	for_each_sg(req->src, sg, nents, i)
169 		sr->in.total_bytes += sg_dma_len(sg);
170 
171 	sr->in.sg = req->src;
172 	sr->in.sgmap_cnt = nents;
173 	ret = create_sg_component(sr, &sr->in, sr->in.sgmap_cnt);
174 	if (ret)
175 		goto incomp_err;
176 
177 	return 0;
178 
179 incomp_err:
180 	dma_unmap_sg(dev, req->src, nents, DMA_BIDIRECTIONAL);
181 	sr->in.sgmap_cnt = 0;
182 	return ret;
183 }
184 
185 static int dma_map_outbufs(struct nitrox_softreq *sr,
186 			   struct se_crypto_request *req)
187 {
188 	struct device *dev = DEV(sr->ndev);
189 	int nents, ret = 0;
190 
191 	nents = dma_map_sg(dev, req->dst, sg_nents(req->dst),
192 			   DMA_BIDIRECTIONAL);
193 	if (!nents)
194 		return -EINVAL;
195 
196 	sr->out.sg = req->dst;
197 	sr->out.sgmap_cnt = nents;
198 	ret = create_sg_component(sr, &sr->out, sr->out.sgmap_cnt);
199 	if (ret)
200 		goto outcomp_map_err;
201 
202 	return 0;
203 
204 outcomp_map_err:
205 	dma_unmap_sg(dev, req->dst, nents, DMA_BIDIRECTIONAL);
206 	sr->out.sgmap_cnt = 0;
207 	sr->out.sg = NULL;
208 	return ret;
209 }
210 
211 static inline int softreq_map_iobuf(struct nitrox_softreq *sr,
212 				    struct se_crypto_request *creq)
213 {
214 	int ret;
215 
216 	ret = dma_map_inbufs(sr, creq);
217 	if (ret)
218 		return ret;
219 
220 	ret = dma_map_outbufs(sr, creq);
221 	if (ret)
222 		softreq_unmap_sgbufs(sr);
223 
224 	return ret;
225 }
226 
227 static inline void backlog_list_add(struct nitrox_softreq *sr,
228 				    struct nitrox_cmdq *cmdq)
229 {
230 	INIT_LIST_HEAD(&sr->backlog);
231 
232 	spin_lock_bh(&cmdq->backlog_qlock);
233 	list_add_tail(&sr->backlog, &cmdq->backlog_head);
234 	atomic_inc(&cmdq->backlog_count);
235 	atomic_set(&sr->status, REQ_BACKLOG);
236 	spin_unlock_bh(&cmdq->backlog_qlock);
237 }
238 
239 static inline void response_list_add(struct nitrox_softreq *sr,
240 				     struct nitrox_cmdq *cmdq)
241 {
242 	INIT_LIST_HEAD(&sr->response);
243 
244 	spin_lock_bh(&cmdq->resp_qlock);
245 	list_add_tail(&sr->response, &cmdq->response_head);
246 	spin_unlock_bh(&cmdq->resp_qlock);
247 }
248 
249 static inline void response_list_del(struct nitrox_softreq *sr,
250 				     struct nitrox_cmdq *cmdq)
251 {
252 	spin_lock_bh(&cmdq->resp_qlock);
253 	list_del(&sr->response);
254 	spin_unlock_bh(&cmdq->resp_qlock);
255 }
256 
257 static struct nitrox_softreq *
258 get_first_response_entry(struct nitrox_cmdq *cmdq)
259 {
260 	return list_first_entry_or_null(&cmdq->response_head,
261 					struct nitrox_softreq, response);
262 }
263 
264 static inline bool cmdq_full(struct nitrox_cmdq *cmdq, int qlen)
265 {
266 	if (atomic_inc_return(&cmdq->pending_count) > qlen) {
267 		atomic_dec(&cmdq->pending_count);
268 		/* sync with other cpus */
269 		smp_mb__after_atomic();
270 		return true;
271 	}
272 	return false;
273 }
274 
275 /**
276  * post_se_instr - Post SE instruction to Packet Input ring
277  * @sr: Request structure
278  *
279  * Returns 0 if successful or a negative error code,
280  * if no space in ring.
281  */
282 static void post_se_instr(struct nitrox_softreq *sr,
283 			  struct nitrox_cmdq *cmdq)
284 {
285 	struct nitrox_device *ndev = sr->ndev;
286 	int idx;
287 	u8 *ent;
288 
289 	spin_lock_bh(&cmdq->cmd_qlock);
290 
291 	idx = cmdq->write_idx;
292 	/* copy the instruction */
293 	ent = cmdq->base + (idx * cmdq->instr_size);
294 	memcpy(ent, &sr->instr, cmdq->instr_size);
295 
296 	atomic_set(&sr->status, REQ_POSTED);
297 	response_list_add(sr, cmdq);
298 	sr->tstamp = jiffies;
299 	/* flush the command queue updates */
300 	dma_wmb();
301 
302 	/* Ring doorbell with count 1 */
303 	writeq(1, cmdq->dbell_csr_addr);
304 	/* orders the doorbell rings */
305 	mmiowb();
306 
307 	cmdq->write_idx = incr_index(idx, 1, ndev->qlen);
308 
309 	spin_unlock_bh(&cmdq->cmd_qlock);
310 
311 	/* increment the posted command count */
312 	atomic64_inc(&ndev->stats.posted);
313 }
314 
315 static int post_backlog_cmds(struct nitrox_cmdq *cmdq)
316 {
317 	struct nitrox_device *ndev = cmdq->ndev;
318 	struct nitrox_softreq *sr, *tmp;
319 	int ret = 0;
320 
321 	if (!atomic_read(&cmdq->backlog_count))
322 		return 0;
323 
324 	spin_lock_bh(&cmdq->backlog_qlock);
325 
326 	list_for_each_entry_safe(sr, tmp, &cmdq->backlog_head, backlog) {
327 		struct skcipher_request *skreq;
328 
329 		/* submit until space available */
330 		if (unlikely(cmdq_full(cmdq, ndev->qlen))) {
331 			ret = -ENOSPC;
332 			break;
333 		}
334 		/* delete from backlog list */
335 		list_del(&sr->backlog);
336 		atomic_dec(&cmdq->backlog_count);
337 		/* sync with other cpus */
338 		smp_mb__after_atomic();
339 
340 		skreq = sr->skreq;
341 		/* post the command */
342 		post_se_instr(sr, cmdq);
343 
344 		/* backlog requests are posted, wakeup with -EINPROGRESS */
345 		skcipher_request_complete(skreq, -EINPROGRESS);
346 	}
347 	spin_unlock_bh(&cmdq->backlog_qlock);
348 
349 	return ret;
350 }
351 
352 static int nitrox_enqueue_request(struct nitrox_softreq *sr)
353 {
354 	struct nitrox_cmdq *cmdq = sr->cmdq;
355 	struct nitrox_device *ndev = sr->ndev;
356 
357 	/* try to post backlog requests */
358 	post_backlog_cmds(cmdq);
359 
360 	if (unlikely(cmdq_full(cmdq, ndev->qlen))) {
361 		if (!(sr->flags & CRYPTO_TFM_REQ_MAY_BACKLOG)) {
362 			/* increment drop count */
363 			atomic64_inc(&ndev->stats.dropped);
364 			return -ENOSPC;
365 		}
366 		/* add to backlog list */
367 		backlog_list_add(sr, cmdq);
368 		return -EBUSY;
369 	}
370 	post_se_instr(sr, cmdq);
371 
372 	return -EINPROGRESS;
373 }
374 
375 /**
376  * nitrox_se_request - Send request to SE core
377  * @ndev: NITROX device
378  * @req: Crypto request
379  *
380  * Returns 0 on success, or a negative error code.
381  */
382 int nitrox_process_se_request(struct nitrox_device *ndev,
383 			      struct se_crypto_request *req,
384 			      completion_t callback,
385 			      struct skcipher_request *skreq)
386 {
387 	struct nitrox_softreq *sr;
388 	dma_addr_t ctx_handle = 0;
389 	int qno, ret = 0;
390 
391 	if (!nitrox_ready(ndev))
392 		return -ENODEV;
393 
394 	sr = kzalloc(sizeof(*sr), req->gfp);
395 	if (!sr)
396 		return -ENOMEM;
397 
398 	sr->ndev = ndev;
399 	sr->flags = req->flags;
400 	sr->gfp = req->gfp;
401 	sr->callback = callback;
402 	sr->skreq = skreq;
403 
404 	atomic_set(&sr->status, REQ_NOT_POSTED);
405 
406 	sr->resp.orh = req->orh;
407 	sr->resp.completion = req->comp;
408 
409 	ret = softreq_map_iobuf(sr, req);
410 	if (ret) {
411 		kfree(sr);
412 		return ret;
413 	}
414 
415 	/* get the context handle */
416 	if (req->ctx_handle) {
417 		struct ctx_hdr *hdr;
418 		u8 *ctx_ptr;
419 
420 		ctx_ptr = (u8 *)(uintptr_t)req->ctx_handle;
421 		hdr = (struct ctx_hdr *)(ctx_ptr - sizeof(struct ctx_hdr));
422 		ctx_handle = hdr->ctx_dma;
423 	}
424 
425 	/* select the queue */
426 	qno = smp_processor_id() % ndev->nr_queues;
427 
428 	sr->cmdq = &ndev->pkt_inq[qno];
429 
430 	/*
431 	 * 64-Byte Instruction Format
432 	 *
433 	 *  ----------------------
434 	 *  |      DPTR0         | 8 bytes
435 	 *  ----------------------
436 	 *  |  PKT_IN_INSTR_HDR  | 8 bytes
437 	 *  ----------------------
438 	 *  |    PKT_IN_HDR      | 16 bytes
439 	 *  ----------------------
440 	 *  |    SLC_INFO        | 16 bytes
441 	 *  ----------------------
442 	 *  |   Front data       | 16 bytes
443 	 *  ----------------------
444 	 */
445 
446 	/* fill the packet instruction */
447 	/* word 0 */
448 	sr->instr.dptr0 = cpu_to_be64(sr->in.sgcomp_dma);
449 
450 	/* word 1 */
451 	sr->instr.ih.value = 0;
452 	sr->instr.ih.s.g = 1;
453 	sr->instr.ih.s.gsz = sr->in.sgmap_cnt;
454 	sr->instr.ih.s.ssz = sr->out.sgmap_cnt;
455 	sr->instr.ih.s.fsz = FDATA_SIZE + sizeof(struct gphdr);
456 	sr->instr.ih.s.tlen = sr->instr.ih.s.fsz + sr->in.total_bytes;
457 	sr->instr.ih.value = cpu_to_be64(sr->instr.ih.value);
458 
459 	/* word 2 */
460 	sr->instr.irh.value[0] = 0;
461 	sr->instr.irh.s.uddl = MIN_UDD_LEN;
462 	/* context length in 64-bit words */
463 	sr->instr.irh.s.ctxl = (req->ctrl.s.ctxl / 8);
464 	/* offset from solicit base port 256 */
465 	sr->instr.irh.s.destport = SOLICIT_BASE_DPORT + qno;
466 	sr->instr.irh.s.ctxc = req->ctrl.s.ctxc;
467 	sr->instr.irh.s.arg = req->ctrl.s.arg;
468 	sr->instr.irh.s.opcode = req->opcode;
469 	sr->instr.irh.value[0] = cpu_to_be64(sr->instr.irh.value[0]);
470 
471 	/* word 3 */
472 	sr->instr.irh.s.ctxp = cpu_to_be64(ctx_handle);
473 
474 	/* word 4 */
475 	sr->instr.slc.value[0] = 0;
476 	sr->instr.slc.s.ssz = sr->out.sgmap_cnt;
477 	sr->instr.slc.value[0] = cpu_to_be64(sr->instr.slc.value[0]);
478 
479 	/* word 5 */
480 	sr->instr.slc.s.rptr = cpu_to_be64(sr->out.sgcomp_dma);
481 
482 	/*
483 	 * No conversion for front data,
484 	 * It goes into payload
485 	 * put GP Header in front data
486 	 */
487 	sr->instr.fdata[0] = *((u64 *)&req->gph);
488 	sr->instr.fdata[1] = 0;
489 
490 	ret = nitrox_enqueue_request(sr);
491 	if (ret == -ENOSPC)
492 		goto send_fail;
493 
494 	return ret;
495 
496 send_fail:
497 	softreq_destroy(sr);
498 	return ret;
499 }
500 
501 static inline int cmd_timeout(unsigned long tstamp, unsigned long timeout)
502 {
503 	return time_after_eq(jiffies, (tstamp + timeout));
504 }
505 
506 void backlog_qflush_work(struct work_struct *work)
507 {
508 	struct nitrox_cmdq *cmdq;
509 
510 	cmdq = container_of(work, struct nitrox_cmdq, backlog_qflush);
511 	post_backlog_cmds(cmdq);
512 }
513 
514 static bool sr_completed(struct nitrox_softreq *sr)
515 {
516 	return (READ_ONCE(*sr->resp.orh) != READ_ONCE(*sr->resp.completion));
517 }
518 
519 /**
520  * process_request_list - process completed requests
521  * @ndev: N5 device
522  * @qno: queue to operate
523  *
524  * Returns the number of responses processed.
525  */
526 static void process_response_list(struct nitrox_cmdq *cmdq)
527 {
528 	struct nitrox_device *ndev = cmdq->ndev;
529 	struct nitrox_softreq *sr;
530 	struct skcipher_request *skreq;
531 	completion_t callback;
532 	int req_completed = 0, err = 0, budget;
533 
534 	/* check all pending requests */
535 	budget = atomic_read(&cmdq->pending_count);
536 
537 	while (req_completed < budget) {
538 		sr = get_first_response_entry(cmdq);
539 		if (!sr)
540 			break;
541 
542 		if (atomic_read(&sr->status) != REQ_POSTED)
543 			break;
544 
545 		/* check orh and completion bytes updates */
546 		if (!sr_completed(sr)) {
547 			/* request not completed, check for timeout */
548 			if (!cmd_timeout(sr->tstamp, ndev->timeout))
549 				break;
550 			dev_err_ratelimited(DEV(ndev),
551 					    "Request timeout, orh 0x%016llx\n",
552 					    READ_ONCE(*sr->resp.orh));
553 		}
554 		atomic_dec(&cmdq->pending_count);
555 		atomic64_inc(&ndev->stats.completed);
556 		/* sync with other cpus */
557 		smp_mb__after_atomic();
558 		/* remove from response list */
559 		response_list_del(sr, cmdq);
560 
561 		callback = sr->callback;
562 		skreq = sr->skreq;
563 
564 		/* ORH error code */
565 		err = READ_ONCE(*sr->resp.orh) & 0xff;
566 		softreq_destroy(sr);
567 
568 		if (callback)
569 			callback(skreq, err);
570 
571 		req_completed++;
572 	}
573 }
574 
575 /**
576  * pkt_slc_resp_tasklet - post processing of SE responses
577  */
578 void pkt_slc_resp_tasklet(unsigned long data)
579 {
580 	struct nitrox_q_vector *qvec = (void *)(uintptr_t)(data);
581 	struct nitrox_cmdq *cmdq = qvec->cmdq;
582 	union nps_pkt_slc_cnts slc_cnts;
583 
584 	/* read completion count */
585 	slc_cnts.value = readq(cmdq->compl_cnt_csr_addr);
586 	/* resend the interrupt if more work to do */
587 	slc_cnts.s.resend = 1;
588 
589 	process_response_list(cmdq);
590 
591 	/*
592 	 * clear the interrupt with resend bit enabled,
593 	 * MSI-X interrupt generates if Completion count > Threshold
594 	 */
595 	writeq(slc_cnts.value, cmdq->compl_cnt_csr_addr);
596 	/* order the writes */
597 	mmiowb();
598 
599 	if (atomic_read(&cmdq->backlog_count))
600 		schedule_work(&cmdq->backlog_qflush);
601 }
602