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_common.h"
7 #include "nitrox_dev.h"
8 #include "nitrox_req.h"
9 #include "nitrox_csr.h"
10 
11 /* SLC_STORE_INFO */
12 #define MIN_UDD_LEN 16
13 /* PKT_IN_HDR + SLC_STORE_INFO */
14 #define FDATA_SIZE 32
15 /* Base destination port for the solicited requests */
16 #define SOLICIT_BASE_DPORT 256
17 
18 #define REQ_NOT_POSTED 1
19 #define REQ_BACKLOG    2
20 #define REQ_POSTED     3
21 
22 /**
23  * Response codes from SE microcode
24  * 0x00 - Success
25  *   Completion with no error
26  * 0x43 - ERR_GC_DATA_LEN_INVALID
27  *   Invalid Data length if Encryption Data length is
28  *   less than 16 bytes for AES-XTS and AES-CTS.
29  * 0x45 - ERR_GC_CTX_LEN_INVALID
30  *   Invalid context length: CTXL != 23 words.
31  * 0x4F - ERR_GC_DOCSIS_CIPHER_INVALID
32  *   DOCSIS support is enabled with other than
33  *   AES/DES-CBC mode encryption.
34  * 0x50 - ERR_GC_DOCSIS_OFFSET_INVALID
35  *   Authentication offset is other than 0 with
36  *   Encryption IV source = 0.
37  *   Authentication offset is other than 8 (DES)/16 (AES)
38  *   with Encryption IV source = 1
39  * 0x51 - ERR_GC_CRC32_INVALID_SELECTION
40  *   CRC32 is enabled for other than DOCSIS encryption.
41  * 0x52 - ERR_GC_AES_CCM_FLAG_INVALID
42  *   Invalid flag options in AES-CCM IV.
43  */
44 
45 static inline int incr_index(int index, int count, int max)
46 {
47 	if ((index + count) >= max)
48 		index = index + count - max;
49 	else
50 		index += count;
51 
52 	return index;
53 }
54 
55 static void softreq_unmap_sgbufs(struct nitrox_softreq *sr)
56 {
57 	struct nitrox_device *ndev = sr->ndev;
58 	struct device *dev = DEV(ndev);
59 
60 
61 	dma_unmap_sg(dev, sr->in.sg, sr->in.sgmap_cnt, DMA_BIDIRECTIONAL);
62 	dma_unmap_single(dev, sr->in.sgcomp_dma, sr->in.sgcomp_len,
63 			 DMA_TO_DEVICE);
64 	kfree(sr->in.sgcomp);
65 	sr->in.sg = NULL;
66 	sr->in.sgmap_cnt = 0;
67 
68 	dma_unmap_sg(dev, sr->out.sg, sr->out.sgmap_cnt,
69 		     DMA_BIDIRECTIONAL);
70 	dma_unmap_single(dev, sr->out.sgcomp_dma, sr->out.sgcomp_len,
71 			 DMA_TO_DEVICE);
72 	kfree(sr->out.sgcomp);
73 	sr->out.sg = NULL;
74 	sr->out.sgmap_cnt = 0;
75 }
76 
77 static void softreq_destroy(struct nitrox_softreq *sr)
78 {
79 	softreq_unmap_sgbufs(sr);
80 	kfree(sr);
81 }
82 
83 /**
84  * create_sg_component - create SG componets for N5 device.
85  * @sr: Request structure
86  * @sgtbl: SG table
87  * @map_nents: number of dma mapped entries
88  *
89  * Component structure
90  *
91  *   63     48 47     32 31    16 15      0
92  *   --------------------------------------
93  *   |   LEN0  |  LEN1  |  LEN2  |  LEN3  |
94  *   |-------------------------------------
95  *   |               PTR0                 |
96  *   --------------------------------------
97  *   |               PTR1                 |
98  *   --------------------------------------
99  *   |               PTR2                 |
100  *   --------------------------------------
101  *   |               PTR3                 |
102  *   --------------------------------------
103  *
104  *   Returns 0 if success or a negative errno code on error.
105  */
106 static int create_sg_component(struct nitrox_softreq *sr,
107 			       struct nitrox_sgtable *sgtbl, int map_nents)
108 {
109 	struct nitrox_device *ndev = sr->ndev;
110 	struct nitrox_sgcomp *sgcomp;
111 	struct scatterlist *sg;
112 	dma_addr_t dma;
113 	size_t sz_comp;
114 	int i, j, nr_sgcomp;
115 
116 	nr_sgcomp = roundup(map_nents, 4) / 4;
117 
118 	/* each component holds 4 dma pointers */
119 	sz_comp = nr_sgcomp * sizeof(*sgcomp);
120 	sgcomp = kzalloc(sz_comp, sr->gfp);
121 	if (!sgcomp)
122 		return -ENOMEM;
123 
124 	sgtbl->sgcomp = sgcomp;
125 
126 	sg = sgtbl->sg;
127 	/* populate device sg component */
128 	for (i = 0; i < nr_sgcomp; i++) {
129 		for (j = 0; j < 4 && sg; j++) {
130 			sgcomp[i].len[j] = cpu_to_be16(sg_dma_len(sg));
131 			sgcomp[i].dma[j] = cpu_to_be64(sg_dma_address(sg));
132 			sg = sg_next(sg);
133 		}
134 	}
135 	/* map the device sg component */
136 	dma = dma_map_single(DEV(ndev), sgtbl->sgcomp, sz_comp, DMA_TO_DEVICE);
137 	if (dma_mapping_error(DEV(ndev), dma)) {
138 		kfree(sgtbl->sgcomp);
139 		sgtbl->sgcomp = NULL;
140 		return -ENOMEM;
141 	}
142 
143 	sgtbl->sgcomp_dma = dma;
144 	sgtbl->sgcomp_len = sz_comp;
145 
146 	return 0;
147 }
148 
149 /**
150  * dma_map_inbufs - DMA map input sglist and creates sglist component
151  *                  for N5 device.
152  * @sr: Request structure
153  * @req: Crypto request structre
154  *
155  * Returns 0 if successful or a negative errno code on error.
156  */
157 static int dma_map_inbufs(struct nitrox_softreq *sr,
158 			  struct se_crypto_request *req)
159 {
160 	struct device *dev = DEV(sr->ndev);
161 	struct scatterlist *sg = req->src;
162 	int i, nents, ret = 0;
163 
164 	nents = dma_map_sg(dev, req->src, sg_nents(req->src),
165 			   DMA_BIDIRECTIONAL);
166 	if (!nents)
167 		return -EINVAL;
168 
169 	for_each_sg(req->src, sg, nents, i)
170 		sr->in.total_bytes += sg_dma_len(sg);
171 
172 	sr->in.sg = req->src;
173 	sr->in.sgmap_cnt = nents;
174 	ret = create_sg_component(sr, &sr->in, sr->in.sgmap_cnt);
175 	if (ret)
176 		goto incomp_err;
177 
178 	return 0;
179 
180 incomp_err:
181 	dma_unmap_sg(dev, req->src, nents, DMA_BIDIRECTIONAL);
182 	sr->in.sgmap_cnt = 0;
183 	return ret;
184 }
185 
186 static int dma_map_outbufs(struct nitrox_softreq *sr,
187 			   struct se_crypto_request *req)
188 {
189 	struct device *dev = DEV(sr->ndev);
190 	int nents, ret = 0;
191 
192 	nents = dma_map_sg(dev, req->dst, sg_nents(req->dst),
193 			   DMA_BIDIRECTIONAL);
194 	if (!nents)
195 		return -EINVAL;
196 
197 	sr->out.sg = req->dst;
198 	sr->out.sgmap_cnt = nents;
199 	ret = create_sg_component(sr, &sr->out, sr->out.sgmap_cnt);
200 	if (ret)
201 		goto outcomp_map_err;
202 
203 	return 0;
204 
205 outcomp_map_err:
206 	dma_unmap_sg(dev, req->dst, nents, DMA_BIDIRECTIONAL);
207 	sr->out.sgmap_cnt = 0;
208 	sr->out.sg = NULL;
209 	return ret;
210 }
211 
212 static inline int softreq_map_iobuf(struct nitrox_softreq *sr,
213 				    struct se_crypto_request *creq)
214 {
215 	int ret;
216 
217 	ret = dma_map_inbufs(sr, creq);
218 	if (ret)
219 		return ret;
220 
221 	ret = dma_map_outbufs(sr, creq);
222 	if (ret)
223 		softreq_unmap_sgbufs(sr);
224 
225 	return ret;
226 }
227 
228 static inline void backlog_list_add(struct nitrox_softreq *sr,
229 				    struct nitrox_cmdq *cmdq)
230 {
231 	INIT_LIST_HEAD(&sr->backlog);
232 
233 	spin_lock_bh(&cmdq->backlog_qlock);
234 	list_add_tail(&sr->backlog, &cmdq->backlog_head);
235 	atomic_inc(&cmdq->backlog_count);
236 	atomic_set(&sr->status, REQ_BACKLOG);
237 	spin_unlock_bh(&cmdq->backlog_qlock);
238 }
239 
240 static inline void response_list_add(struct nitrox_softreq *sr,
241 				     struct nitrox_cmdq *cmdq)
242 {
243 	INIT_LIST_HEAD(&sr->response);
244 
245 	spin_lock_bh(&cmdq->resp_qlock);
246 	list_add_tail(&sr->response, &cmdq->response_head);
247 	spin_unlock_bh(&cmdq->resp_qlock);
248 }
249 
250 static inline void response_list_del(struct nitrox_softreq *sr,
251 				     struct nitrox_cmdq *cmdq)
252 {
253 	spin_lock_bh(&cmdq->resp_qlock);
254 	list_del(&sr->response);
255 	spin_unlock_bh(&cmdq->resp_qlock);
256 }
257 
258 static struct nitrox_softreq *
259 get_first_response_entry(struct nitrox_cmdq *cmdq)
260 {
261 	return list_first_entry_or_null(&cmdq->response_head,
262 					struct nitrox_softreq, response);
263 }
264 
265 static inline bool cmdq_full(struct nitrox_cmdq *cmdq, int qlen)
266 {
267 	if (atomic_inc_return(&cmdq->pending_count) > qlen) {
268 		atomic_dec(&cmdq->pending_count);
269 		/* sync with other cpus */
270 		smp_mb__after_atomic();
271 		return true;
272 	}
273 	/* sync with other cpus */
274 	smp_mb__after_atomic();
275 	return false;
276 }
277 
278 /**
279  * post_se_instr - Post SE instruction to Packet Input ring
280  * @sr: Request structure
281  *
282  * Returns 0 if successful or a negative error code,
283  * if no space in ring.
284  */
285 static void post_se_instr(struct nitrox_softreq *sr,
286 			  struct nitrox_cmdq *cmdq)
287 {
288 	struct nitrox_device *ndev = sr->ndev;
289 	int idx;
290 	u8 *ent;
291 
292 	spin_lock_bh(&cmdq->cmd_qlock);
293 
294 	idx = cmdq->write_idx;
295 	/* copy the instruction */
296 	ent = cmdq->base + (idx * cmdq->instr_size);
297 	memcpy(ent, &sr->instr, cmdq->instr_size);
298 
299 	atomic_set(&sr->status, REQ_POSTED);
300 	response_list_add(sr, cmdq);
301 	sr->tstamp = jiffies;
302 	/* flush the command queue updates */
303 	dma_wmb();
304 
305 	/* Ring doorbell with count 1 */
306 	writeq(1, cmdq->dbell_csr_addr);
307 
308 	cmdq->write_idx = incr_index(idx, 1, ndev->qlen);
309 
310 	spin_unlock_bh(&cmdq->cmd_qlock);
311 
312 	/* increment the posted command count */
313 	atomic64_inc(&ndev->stats.posted);
314 }
315 
316 static int post_backlog_cmds(struct nitrox_cmdq *cmdq)
317 {
318 	struct nitrox_device *ndev = cmdq->ndev;
319 	struct nitrox_softreq *sr, *tmp;
320 	int ret = 0;
321 
322 	if (!atomic_read(&cmdq->backlog_count))
323 		return 0;
324 
325 	spin_lock_bh(&cmdq->backlog_qlock);
326 
327 	list_for_each_entry_safe(sr, tmp, &cmdq->backlog_head, backlog) {
328 		/* submit until space available */
329 		if (unlikely(cmdq_full(cmdq, ndev->qlen))) {
330 			ret = -ENOSPC;
331 			break;
332 		}
333 		/* delete from backlog list */
334 		list_del(&sr->backlog);
335 		atomic_dec(&cmdq->backlog_count);
336 		/* sync with other cpus */
337 		smp_mb__after_atomic();
338 
339 		/* post the command */
340 		post_se_instr(sr, cmdq);
341 	}
342 	spin_unlock_bh(&cmdq->backlog_qlock);
343 
344 	return ret;
345 }
346 
347 static int nitrox_enqueue_request(struct nitrox_softreq *sr)
348 {
349 	struct nitrox_cmdq *cmdq = sr->cmdq;
350 	struct nitrox_device *ndev = sr->ndev;
351 
352 	/* try to post backlog requests */
353 	post_backlog_cmds(cmdq);
354 
355 	if (unlikely(cmdq_full(cmdq, ndev->qlen))) {
356 		if (!(sr->flags & CRYPTO_TFM_REQ_MAY_BACKLOG)) {
357 			/* increment drop count */
358 			atomic64_inc(&ndev->stats.dropped);
359 			return -ENOSPC;
360 		}
361 		/* add to backlog list */
362 		backlog_list_add(sr, cmdq);
363 		return -EINPROGRESS;
364 	}
365 	post_se_instr(sr, cmdq);
366 
367 	return -EINPROGRESS;
368 }
369 
370 /**
371  * nitrox_se_request - Send request to SE core
372  * @ndev: NITROX device
373  * @req: Crypto request
374  *
375  * Returns 0 on success, or a negative error code.
376  */
377 int nitrox_process_se_request(struct nitrox_device *ndev,
378 			      struct se_crypto_request *req,
379 			      completion_t callback,
380 			      void *cb_arg)
381 {
382 	struct nitrox_softreq *sr;
383 	dma_addr_t ctx_handle = 0;
384 	int qno, ret = 0;
385 
386 	if (!nitrox_ready(ndev))
387 		return -ENODEV;
388 
389 	sr = kzalloc(sizeof(*sr), req->gfp);
390 	if (!sr)
391 		return -ENOMEM;
392 
393 	sr->ndev = ndev;
394 	sr->flags = req->flags;
395 	sr->gfp = req->gfp;
396 	sr->callback = callback;
397 	sr->cb_arg = cb_arg;
398 
399 	atomic_set(&sr->status, REQ_NOT_POSTED);
400 
401 	sr->resp.orh = req->orh;
402 	sr->resp.completion = req->comp;
403 
404 	ret = softreq_map_iobuf(sr, req);
405 	if (ret) {
406 		kfree(sr);
407 		return ret;
408 	}
409 
410 	/* get the context handle */
411 	if (req->ctx_handle) {
412 		struct ctx_hdr *hdr;
413 		u8 *ctx_ptr;
414 
415 		ctx_ptr = (u8 *)(uintptr_t)req->ctx_handle;
416 		hdr = (struct ctx_hdr *)(ctx_ptr - sizeof(struct ctx_hdr));
417 		ctx_handle = hdr->ctx_dma;
418 	}
419 
420 	/* select the queue */
421 	qno = smp_processor_id() % ndev->nr_queues;
422 
423 	sr->cmdq = &ndev->pkt_inq[qno];
424 
425 	/*
426 	 * 64-Byte Instruction Format
427 	 *
428 	 *  ----------------------
429 	 *  |      DPTR0         | 8 bytes
430 	 *  ----------------------
431 	 *  |  PKT_IN_INSTR_HDR  | 8 bytes
432 	 *  ----------------------
433 	 *  |    PKT_IN_HDR      | 16 bytes
434 	 *  ----------------------
435 	 *  |    SLC_INFO        | 16 bytes
436 	 *  ----------------------
437 	 *  |   Front data       | 16 bytes
438 	 *  ----------------------
439 	 */
440 
441 	/* fill the packet instruction */
442 	/* word 0 */
443 	sr->instr.dptr0 = cpu_to_be64(sr->in.sgcomp_dma);
444 
445 	/* word 1 */
446 	sr->instr.ih.value = 0;
447 	sr->instr.ih.s.g = 1;
448 	sr->instr.ih.s.gsz = sr->in.sgmap_cnt;
449 	sr->instr.ih.s.ssz = sr->out.sgmap_cnt;
450 	sr->instr.ih.s.fsz = FDATA_SIZE + sizeof(struct gphdr);
451 	sr->instr.ih.s.tlen = sr->instr.ih.s.fsz + sr->in.total_bytes;
452 	sr->instr.ih.bev = cpu_to_be64(sr->instr.ih.value);
453 
454 	/* word 2 */
455 	sr->instr.irh.value[0] = 0;
456 	sr->instr.irh.s.uddl = MIN_UDD_LEN;
457 	/* context length in 64-bit words */
458 	sr->instr.irh.s.ctxl = (req->ctrl.s.ctxl / 8);
459 	/* offset from solicit base port 256 */
460 	sr->instr.irh.s.destport = SOLICIT_BASE_DPORT + qno;
461 	sr->instr.irh.s.ctxc = req->ctrl.s.ctxc;
462 	sr->instr.irh.s.arg = req->ctrl.s.arg;
463 	sr->instr.irh.s.opcode = req->opcode;
464 	sr->instr.irh.bev[0] = cpu_to_be64(sr->instr.irh.value[0]);
465 
466 	/* word 3 */
467 	sr->instr.irh.s.ctxp = cpu_to_be64(ctx_handle);
468 
469 	/* word 4 */
470 	sr->instr.slc.value[0] = 0;
471 	sr->instr.slc.s.ssz = sr->out.sgmap_cnt;
472 	sr->instr.slc.bev[0] = cpu_to_be64(sr->instr.slc.value[0]);
473 
474 	/* word 5 */
475 	sr->instr.slc.s.rptr = cpu_to_be64(sr->out.sgcomp_dma);
476 
477 	/*
478 	 * No conversion for front data,
479 	 * It goes into payload
480 	 * put GP Header in front data
481 	 */
482 	sr->instr.fdata[0] = *((u64 *)&req->gph);
483 	sr->instr.fdata[1] = 0;
484 
485 	ret = nitrox_enqueue_request(sr);
486 	if (ret == -ENOSPC)
487 		goto send_fail;
488 
489 	return ret;
490 
491 send_fail:
492 	softreq_destroy(sr);
493 	return ret;
494 }
495 
496 static inline int cmd_timeout(unsigned long tstamp, unsigned long timeout)
497 {
498 	return time_after_eq(jiffies, (tstamp + timeout));
499 }
500 
501 void backlog_qflush_work(struct work_struct *work)
502 {
503 	struct nitrox_cmdq *cmdq;
504 
505 	cmdq = container_of(work, struct nitrox_cmdq, backlog_qflush);
506 	post_backlog_cmds(cmdq);
507 }
508 
509 static bool sr_completed(struct nitrox_softreq *sr)
510 {
511 	u64 orh = READ_ONCE(*sr->resp.orh);
512 	unsigned long timeout = jiffies + msecs_to_jiffies(1);
513 
514 	if ((orh != PENDING_SIG) && (orh & 0xff))
515 		return true;
516 
517 	while (READ_ONCE(*sr->resp.completion) == PENDING_SIG) {
518 		if (time_after(jiffies, timeout)) {
519 			pr_err("comp not done\n");
520 			return false;
521 		}
522 	}
523 
524 	return true;
525 }
526 
527 /**
528  * process_request_list - process completed requests
529  * @ndev: N5 device
530  * @qno: queue to operate
531  *
532  * Returns the number of responses processed.
533  */
534 static void process_response_list(struct nitrox_cmdq *cmdq)
535 {
536 	struct nitrox_device *ndev = cmdq->ndev;
537 	struct nitrox_softreq *sr;
538 	int req_completed = 0, err = 0, budget;
539 	completion_t callback;
540 	void *cb_arg;
541 
542 	/* check all pending requests */
543 	budget = atomic_read(&cmdq->pending_count);
544 
545 	while (req_completed < budget) {
546 		sr = get_first_response_entry(cmdq);
547 		if (!sr)
548 			break;
549 
550 		if (atomic_read(&sr->status) != REQ_POSTED)
551 			break;
552 
553 		/* check orh and completion bytes updates */
554 		if (!sr_completed(sr)) {
555 			/* request not completed, check for timeout */
556 			if (!cmd_timeout(sr->tstamp, ndev->timeout))
557 				break;
558 			dev_err_ratelimited(DEV(ndev),
559 					    "Request timeout, orh 0x%016llx\n",
560 					    READ_ONCE(*sr->resp.orh));
561 		}
562 		atomic_dec(&cmdq->pending_count);
563 		atomic64_inc(&ndev->stats.completed);
564 		/* sync with other cpus */
565 		smp_mb__after_atomic();
566 		/* remove from response list */
567 		response_list_del(sr, cmdq);
568 		/* ORH error code */
569 		err = READ_ONCE(*sr->resp.orh) & 0xff;
570 		callback = sr->callback;
571 		cb_arg = sr->cb_arg;
572 		softreq_destroy(sr);
573 		if (callback)
574 			callback(cb_arg, err);
575 
576 		req_completed++;
577 	}
578 }
579 
580 /**
581  * pkt_slc_resp_tasklet - post processing of SE responses
582  */
583 void pkt_slc_resp_tasklet(unsigned long data)
584 {
585 	struct nitrox_q_vector *qvec = (void *)(uintptr_t)(data);
586 	struct nitrox_cmdq *cmdq = qvec->cmdq;
587 	union nps_pkt_slc_cnts slc_cnts;
588 
589 	/* read completion count */
590 	slc_cnts.value = readq(cmdq->compl_cnt_csr_addr);
591 	/* resend the interrupt if more work to do */
592 	slc_cnts.s.resend = 1;
593 
594 	process_response_list(cmdq);
595 
596 	/*
597 	 * clear the interrupt with resend bit enabled,
598 	 * MSI-X interrupt generates if Completion count > Threshold
599 	 */
600 	writeq(slc_cnts.value, cmdq->compl_cnt_csr_addr);
601 
602 	if (atomic_read(&cmdq->backlog_count))
603 		schedule_work(&cmdq->backlog_qflush);
604 }
605