xref: /openbmc/linux/drivers/crypto/caam/jr.c (revision 423997ff)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * CAAM/SEC 4.x transport/backend driver
4  * JobR backend functionality
5  *
6  * Copyright 2008-2012 Freescale Semiconductor, Inc.
7  */
8 
9 #include <linux/of_irq.h>
10 #include <linux/of_address.h>
11 
12 #include "compat.h"
13 #include "ctrl.h"
14 #include "regs.h"
15 #include "jr.h"
16 #include "desc.h"
17 #include "intern.h"
18 
19 struct jr_driver_data {
20 	/* List of Physical JobR's with the Driver */
21 	struct list_head	jr_list;
22 	spinlock_t		jr_alloc_lock;	/* jr_list lock */
23 } ____cacheline_aligned;
24 
25 static struct jr_driver_data driver_data;
26 
27 static int caam_reset_hw_jr(struct device *dev)
28 {
29 	struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
30 	unsigned int timeout = 100000;
31 
32 	/*
33 	 * mask interrupts since we are going to poll
34 	 * for reset completion status
35 	 */
36 	clrsetbits_32(&jrp->rregs->rconfig_lo, 0, JRCFG_IMSK);
37 
38 	/* initiate flush (required prior to reset) */
39 	wr_reg32(&jrp->rregs->jrcommand, JRCR_RESET);
40 	while (((rd_reg32(&jrp->rregs->jrintstatus) & JRINT_ERR_HALT_MASK) ==
41 		JRINT_ERR_HALT_INPROGRESS) && --timeout)
42 		cpu_relax();
43 
44 	if ((rd_reg32(&jrp->rregs->jrintstatus) & JRINT_ERR_HALT_MASK) !=
45 	    JRINT_ERR_HALT_COMPLETE || timeout == 0) {
46 		dev_err(dev, "failed to flush job ring %d\n", jrp->ridx);
47 		return -EIO;
48 	}
49 
50 	/* initiate reset */
51 	timeout = 100000;
52 	wr_reg32(&jrp->rregs->jrcommand, JRCR_RESET);
53 	while ((rd_reg32(&jrp->rregs->jrcommand) & JRCR_RESET) && --timeout)
54 		cpu_relax();
55 
56 	if (timeout == 0) {
57 		dev_err(dev, "failed to reset job ring %d\n", jrp->ridx);
58 		return -EIO;
59 	}
60 
61 	/* unmask interrupts */
62 	clrsetbits_32(&jrp->rregs->rconfig_lo, JRCFG_IMSK, 0);
63 
64 	return 0;
65 }
66 
67 /*
68  * Shutdown JobR independent of platform property code
69  */
70 static int caam_jr_shutdown(struct device *dev)
71 {
72 	struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
73 	dma_addr_t inpbusaddr, outbusaddr;
74 	int ret;
75 
76 	ret = caam_reset_hw_jr(dev);
77 
78 	tasklet_kill(&jrp->irqtask);
79 
80 	/* Release interrupt */
81 	free_irq(jrp->irq, dev);
82 
83 	/* Free rings */
84 	inpbusaddr = rd_reg64(&jrp->rregs->inpring_base);
85 	outbusaddr = rd_reg64(&jrp->rregs->outring_base);
86 	dma_free_coherent(dev, sizeof(dma_addr_t) * JOBR_DEPTH,
87 			  jrp->inpring, inpbusaddr);
88 	dma_free_coherent(dev, sizeof(struct jr_outentry) * JOBR_DEPTH,
89 			  jrp->outring, outbusaddr);
90 	kfree(jrp->entinfo);
91 
92 	return ret;
93 }
94 
95 static int caam_jr_remove(struct platform_device *pdev)
96 {
97 	int ret;
98 	struct device *jrdev;
99 	struct caam_drv_private_jr *jrpriv;
100 
101 	jrdev = &pdev->dev;
102 	jrpriv = dev_get_drvdata(jrdev);
103 
104 	/*
105 	 * Return EBUSY if job ring already allocated.
106 	 */
107 	if (atomic_read(&jrpriv->tfm_count)) {
108 		dev_err(jrdev, "Device is busy\n");
109 		return -EBUSY;
110 	}
111 
112 	/* Remove the node from Physical JobR list maintained by driver */
113 	spin_lock(&driver_data.jr_alloc_lock);
114 	list_del(&jrpriv->list_node);
115 	spin_unlock(&driver_data.jr_alloc_lock);
116 
117 	/* Release ring */
118 	ret = caam_jr_shutdown(jrdev);
119 	if (ret)
120 		dev_err(jrdev, "Failed to shut down job ring\n");
121 	irq_dispose_mapping(jrpriv->irq);
122 
123 	return ret;
124 }
125 
126 /* Main per-ring interrupt handler */
127 static irqreturn_t caam_jr_interrupt(int irq, void *st_dev)
128 {
129 	struct device *dev = st_dev;
130 	struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
131 	u32 irqstate;
132 
133 	/*
134 	 * Check the output ring for ready responses, kick
135 	 * tasklet if jobs done.
136 	 */
137 	irqstate = rd_reg32(&jrp->rregs->jrintstatus);
138 	if (!irqstate)
139 		return IRQ_NONE;
140 
141 	/*
142 	 * If JobR error, we got more development work to do
143 	 * Flag a bug now, but we really need to shut down and
144 	 * restart the queue (and fix code).
145 	 */
146 	if (irqstate & JRINT_JR_ERROR) {
147 		dev_err(dev, "job ring error: irqstate: %08x\n", irqstate);
148 		BUG();
149 	}
150 
151 	/* mask valid interrupts */
152 	clrsetbits_32(&jrp->rregs->rconfig_lo, 0, JRCFG_IMSK);
153 
154 	/* Have valid interrupt at this point, just ACK and trigger */
155 	wr_reg32(&jrp->rregs->jrintstatus, irqstate);
156 
157 	preempt_disable();
158 	tasklet_schedule(&jrp->irqtask);
159 	preempt_enable();
160 
161 	return IRQ_HANDLED;
162 }
163 
164 /* Deferred service handler, run as interrupt-fired tasklet */
165 static void caam_jr_dequeue(unsigned long devarg)
166 {
167 	int hw_idx, sw_idx, i, head, tail;
168 	struct device *dev = (struct device *)devarg;
169 	struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
170 	void (*usercall)(struct device *dev, u32 *desc, u32 status, void *arg);
171 	u32 *userdesc, userstatus;
172 	void *userarg;
173 	u32 outring_used = 0;
174 
175 	while (outring_used ||
176 	       (outring_used = rd_reg32(&jrp->rregs->outring_used))) {
177 
178 		head = READ_ONCE(jrp->head);
179 
180 		sw_idx = tail = jrp->tail;
181 		hw_idx = jrp->out_ring_read_index;
182 
183 		for (i = 0; CIRC_CNT(head, tail + i, JOBR_DEPTH) >= 1; i++) {
184 			sw_idx = (tail + i) & (JOBR_DEPTH - 1);
185 
186 			if (jrp->outring[hw_idx].desc ==
187 			    caam_dma_to_cpu(jrp->entinfo[sw_idx].desc_addr_dma))
188 				break; /* found */
189 		}
190 		/* we should never fail to find a matching descriptor */
191 		BUG_ON(CIRC_CNT(head, tail + i, JOBR_DEPTH) <= 0);
192 
193 		/* Unmap just-run descriptor so we can post-process */
194 		dma_unmap_single(dev,
195 				 caam_dma_to_cpu(jrp->outring[hw_idx].desc),
196 				 jrp->entinfo[sw_idx].desc_size,
197 				 DMA_TO_DEVICE);
198 
199 		/* mark completed, avoid matching on a recycled desc addr */
200 		jrp->entinfo[sw_idx].desc_addr_dma = 0;
201 
202 		/* Stash callback params */
203 		usercall = jrp->entinfo[sw_idx].callbk;
204 		userarg = jrp->entinfo[sw_idx].cbkarg;
205 		userdesc = jrp->entinfo[sw_idx].desc_addr_virt;
206 		userstatus = caam32_to_cpu(jrp->outring[hw_idx].jrstatus);
207 
208 		/*
209 		 * Make sure all information from the job has been obtained
210 		 * before telling CAAM that the job has been removed from the
211 		 * output ring.
212 		 */
213 		mb();
214 
215 		/* set done */
216 		wr_reg32(&jrp->rregs->outring_rmvd, 1);
217 
218 		jrp->out_ring_read_index = (jrp->out_ring_read_index + 1) &
219 					   (JOBR_DEPTH - 1);
220 
221 		/*
222 		 * if this job completed out-of-order, do not increment
223 		 * the tail.  Otherwise, increment tail by 1 plus the
224 		 * number of subsequent jobs already completed out-of-order
225 		 */
226 		if (sw_idx == tail) {
227 			do {
228 				tail = (tail + 1) & (JOBR_DEPTH - 1);
229 			} while (CIRC_CNT(head, tail, JOBR_DEPTH) >= 1 &&
230 				 jrp->entinfo[tail].desc_addr_dma == 0);
231 
232 			jrp->tail = tail;
233 		}
234 
235 		/* Finally, execute user's callback */
236 		usercall(dev, userdesc, userstatus, userarg);
237 		outring_used--;
238 	}
239 
240 	/* reenable / unmask IRQs */
241 	clrsetbits_32(&jrp->rregs->rconfig_lo, JRCFG_IMSK, 0);
242 }
243 
244 /**
245  * caam_jr_alloc() - Alloc a job ring for someone to use as needed.
246  *
247  * returns :  pointer to the newly allocated physical
248  *	      JobR dev can be written to if successful.
249  **/
250 struct device *caam_jr_alloc(void)
251 {
252 	struct caam_drv_private_jr *jrpriv, *min_jrpriv = NULL;
253 	struct device *dev = ERR_PTR(-ENODEV);
254 	int min_tfm_cnt	= INT_MAX;
255 	int tfm_cnt;
256 
257 	spin_lock(&driver_data.jr_alloc_lock);
258 
259 	if (list_empty(&driver_data.jr_list)) {
260 		spin_unlock(&driver_data.jr_alloc_lock);
261 		return ERR_PTR(-ENODEV);
262 	}
263 
264 	list_for_each_entry(jrpriv, &driver_data.jr_list, list_node) {
265 		tfm_cnt = atomic_read(&jrpriv->tfm_count);
266 		if (tfm_cnt < min_tfm_cnt) {
267 			min_tfm_cnt = tfm_cnt;
268 			min_jrpriv = jrpriv;
269 		}
270 		if (!min_tfm_cnt)
271 			break;
272 	}
273 
274 	if (min_jrpriv) {
275 		atomic_inc(&min_jrpriv->tfm_count);
276 		dev = min_jrpriv->dev;
277 	}
278 	spin_unlock(&driver_data.jr_alloc_lock);
279 
280 	return dev;
281 }
282 EXPORT_SYMBOL(caam_jr_alloc);
283 
284 /**
285  * caam_jr_free() - Free the Job Ring
286  * @rdev     - points to the dev that identifies the Job ring to
287  *             be released.
288  **/
289 void caam_jr_free(struct device *rdev)
290 {
291 	struct caam_drv_private_jr *jrpriv = dev_get_drvdata(rdev);
292 
293 	atomic_dec(&jrpriv->tfm_count);
294 }
295 EXPORT_SYMBOL(caam_jr_free);
296 
297 /**
298  * caam_jr_enqueue() - Enqueue a job descriptor head. Returns 0 if OK,
299  * -EBUSY if the queue is full, -EIO if it cannot map the caller's
300  * descriptor.
301  * @dev:  device of the job ring to be used. This device should have
302  *        been assigned prior by caam_jr_register().
303  * @desc: points to a job descriptor that execute our request. All
304  *        descriptors (and all referenced data) must be in a DMAable
305  *        region, and all data references must be physical addresses
306  *        accessible to CAAM (i.e. within a PAMU window granted
307  *        to it).
308  * @cbk:  pointer to a callback function to be invoked upon completion
309  *        of this request. This has the form:
310  *        callback(struct device *dev, u32 *desc, u32 stat, void *arg)
311  *        where:
312  *        @dev:    contains the job ring device that processed this
313  *                 response.
314  *        @desc:   descriptor that initiated the request, same as
315  *                 "desc" being argued to caam_jr_enqueue().
316  *        @status: untranslated status received from CAAM. See the
317  *                 reference manual for a detailed description of
318  *                 error meaning, or see the JRSTA definitions in the
319  *                 register header file
320  *        @areq:   optional pointer to an argument passed with the
321  *                 original request
322  * @areq: optional pointer to a user argument for use at callback
323  *        time.
324  **/
325 int caam_jr_enqueue(struct device *dev, u32 *desc,
326 		    void (*cbk)(struct device *dev, u32 *desc,
327 				u32 status, void *areq),
328 		    void *areq)
329 {
330 	struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
331 	struct caam_jrentry_info *head_entry;
332 	int head, tail, desc_size;
333 	dma_addr_t desc_dma;
334 
335 	desc_size = (caam32_to_cpu(*desc) & HDR_JD_LENGTH_MASK) * sizeof(u32);
336 	desc_dma = dma_map_single(dev, desc, desc_size, DMA_TO_DEVICE);
337 	if (dma_mapping_error(dev, desc_dma)) {
338 		dev_err(dev, "caam_jr_enqueue(): can't map jobdesc\n");
339 		return -EIO;
340 	}
341 
342 	spin_lock_bh(&jrp->inplock);
343 
344 	head = jrp->head;
345 	tail = READ_ONCE(jrp->tail);
346 
347 	if (!jrp->inpring_avail ||
348 	    CIRC_SPACE(head, tail, JOBR_DEPTH) <= 0) {
349 		spin_unlock_bh(&jrp->inplock);
350 		dma_unmap_single(dev, desc_dma, desc_size, DMA_TO_DEVICE);
351 		return -EBUSY;
352 	}
353 
354 	head_entry = &jrp->entinfo[head];
355 	head_entry->desc_addr_virt = desc;
356 	head_entry->desc_size = desc_size;
357 	head_entry->callbk = (void *)cbk;
358 	head_entry->cbkarg = areq;
359 	head_entry->desc_addr_dma = desc_dma;
360 
361 	jrp->inpring[head] = cpu_to_caam_dma(desc_dma);
362 
363 	/*
364 	 * Guarantee that the descriptor's DMA address has been written to
365 	 * the next slot in the ring before the write index is updated, since
366 	 * other cores may update this index independently.
367 	 */
368 	smp_wmb();
369 
370 	jrp->head = (head + 1) & (JOBR_DEPTH - 1);
371 
372 	/*
373 	 * Ensure that all job information has been written before
374 	 * notifying CAAM that a new job was added to the input ring
375 	 * using a memory barrier. The wr_reg32() uses api iowrite32()
376 	 * to do the register write. iowrite32() issues a memory barrier
377 	 * before the write operation.
378 	 */
379 
380 	wr_reg32(&jrp->rregs->inpring_jobadd, 1);
381 
382 	jrp->inpring_avail--;
383 	if (!jrp->inpring_avail)
384 		jrp->inpring_avail = rd_reg32(&jrp->rregs->inpring_avail);
385 
386 	spin_unlock_bh(&jrp->inplock);
387 
388 	return 0;
389 }
390 EXPORT_SYMBOL(caam_jr_enqueue);
391 
392 /*
393  * Init JobR independent of platform property detection
394  */
395 static int caam_jr_init(struct device *dev)
396 {
397 	struct caam_drv_private_jr *jrp;
398 	dma_addr_t inpbusaddr, outbusaddr;
399 	int i, error;
400 
401 	jrp = dev_get_drvdata(dev);
402 
403 	tasklet_init(&jrp->irqtask, caam_jr_dequeue, (unsigned long)dev);
404 
405 	/* Connect job ring interrupt handler. */
406 	error = request_irq(jrp->irq, caam_jr_interrupt, IRQF_SHARED,
407 			    dev_name(dev), dev);
408 	if (error) {
409 		dev_err(dev, "can't connect JobR %d interrupt (%d)\n",
410 			jrp->ridx, jrp->irq);
411 		goto out_kill_deq;
412 	}
413 
414 	error = caam_reset_hw_jr(dev);
415 	if (error)
416 		goto out_free_irq;
417 
418 	error = -ENOMEM;
419 	jrp->inpring = dma_alloc_coherent(dev, sizeof(*jrp->inpring) *
420 					  JOBR_DEPTH, &inpbusaddr, GFP_KERNEL);
421 	if (!jrp->inpring)
422 		goto out_free_irq;
423 
424 	jrp->outring = dma_alloc_coherent(dev, sizeof(*jrp->outring) *
425 					  JOBR_DEPTH, &outbusaddr, GFP_KERNEL);
426 	if (!jrp->outring)
427 		goto out_free_inpring;
428 
429 	jrp->entinfo = kcalloc(JOBR_DEPTH, sizeof(*jrp->entinfo), GFP_KERNEL);
430 	if (!jrp->entinfo)
431 		goto out_free_outring;
432 
433 	for (i = 0; i < JOBR_DEPTH; i++)
434 		jrp->entinfo[i].desc_addr_dma = !0;
435 
436 	/* Setup rings */
437 	jrp->out_ring_read_index = 0;
438 	jrp->head = 0;
439 	jrp->tail = 0;
440 
441 	wr_reg64(&jrp->rregs->inpring_base, inpbusaddr);
442 	wr_reg64(&jrp->rregs->outring_base, outbusaddr);
443 	wr_reg32(&jrp->rregs->inpring_size, JOBR_DEPTH);
444 	wr_reg32(&jrp->rregs->outring_size, JOBR_DEPTH);
445 
446 	jrp->inpring_avail = JOBR_DEPTH;
447 
448 	spin_lock_init(&jrp->inplock);
449 
450 	/* Select interrupt coalescing parameters */
451 	clrsetbits_32(&jrp->rregs->rconfig_lo, 0, JOBR_INTC |
452 		      (JOBR_INTC_COUNT_THLD << JRCFG_ICDCT_SHIFT) |
453 		      (JOBR_INTC_TIME_THLD << JRCFG_ICTT_SHIFT));
454 
455 	return 0;
456 
457 out_free_outring:
458 	dma_free_coherent(dev, sizeof(struct jr_outentry) * JOBR_DEPTH,
459 			  jrp->outring, outbusaddr);
460 out_free_inpring:
461 	dma_free_coherent(dev, sizeof(dma_addr_t) * JOBR_DEPTH,
462 			  jrp->inpring, inpbusaddr);
463 	dev_err(dev, "can't allocate job rings for %d\n", jrp->ridx);
464 out_free_irq:
465 	free_irq(jrp->irq, dev);
466 out_kill_deq:
467 	tasklet_kill(&jrp->irqtask);
468 	return error;
469 }
470 
471 
472 /*
473  * Probe routine for each detected JobR subsystem.
474  */
475 static int caam_jr_probe(struct platform_device *pdev)
476 {
477 	struct device *jrdev;
478 	struct device_node *nprop;
479 	struct caam_job_ring __iomem *ctrl;
480 	struct caam_drv_private_jr *jrpriv;
481 	static int total_jobrs;
482 	int error;
483 
484 	jrdev = &pdev->dev;
485 	jrpriv = devm_kmalloc(jrdev, sizeof(*jrpriv), GFP_KERNEL);
486 	if (!jrpriv)
487 		return -ENOMEM;
488 
489 	dev_set_drvdata(jrdev, jrpriv);
490 
491 	/* save ring identity relative to detection */
492 	jrpriv->ridx = total_jobrs++;
493 
494 	nprop = pdev->dev.of_node;
495 	/* Get configuration properties from device tree */
496 	/* First, get register page */
497 	ctrl = of_iomap(nprop, 0);
498 	if (!ctrl) {
499 		dev_err(jrdev, "of_iomap() failed\n");
500 		return -ENOMEM;
501 	}
502 
503 	jrpriv->rregs = (struct caam_job_ring __iomem __force *)ctrl;
504 
505 	if (sizeof(dma_addr_t) == sizeof(u64)) {
506 		if (caam_dpaa2)
507 			error = dma_set_mask_and_coherent(jrdev,
508 							  DMA_BIT_MASK(49));
509 		else if (of_device_is_compatible(nprop,
510 						 "fsl,sec-v5.0-job-ring"))
511 			error = dma_set_mask_and_coherent(jrdev,
512 							  DMA_BIT_MASK(40));
513 		else
514 			error = dma_set_mask_and_coherent(jrdev,
515 							  DMA_BIT_MASK(36));
516 	} else {
517 		error = dma_set_mask_and_coherent(jrdev, DMA_BIT_MASK(32));
518 	}
519 	if (error) {
520 		dev_err(jrdev, "dma_set_mask_and_coherent failed (%d)\n",
521 			error);
522 		iounmap(ctrl);
523 		return error;
524 	}
525 
526 	/* Identify the interrupt */
527 	jrpriv->irq = irq_of_parse_and_map(nprop, 0);
528 
529 	/* Now do the platform independent part */
530 	error = caam_jr_init(jrdev); /* now turn on hardware */
531 	if (error) {
532 		irq_dispose_mapping(jrpriv->irq);
533 		iounmap(ctrl);
534 		return error;
535 	}
536 
537 	jrpriv->dev = jrdev;
538 	spin_lock(&driver_data.jr_alloc_lock);
539 	list_add_tail(&jrpriv->list_node, &driver_data.jr_list);
540 	spin_unlock(&driver_data.jr_alloc_lock);
541 
542 	atomic_set(&jrpriv->tfm_count, 0);
543 
544 	return 0;
545 }
546 
547 static const struct of_device_id caam_jr_match[] = {
548 	{
549 		.compatible = "fsl,sec-v4.0-job-ring",
550 	},
551 	{
552 		.compatible = "fsl,sec4.0-job-ring",
553 	},
554 	{},
555 };
556 MODULE_DEVICE_TABLE(of, caam_jr_match);
557 
558 static struct platform_driver caam_jr_driver = {
559 	.driver = {
560 		.name = "caam_jr",
561 		.of_match_table = caam_jr_match,
562 	},
563 	.probe       = caam_jr_probe,
564 	.remove      = caam_jr_remove,
565 };
566 
567 static int __init jr_driver_init(void)
568 {
569 	spin_lock_init(&driver_data.jr_alloc_lock);
570 	INIT_LIST_HEAD(&driver_data.jr_list);
571 	return platform_driver_register(&caam_jr_driver);
572 }
573 
574 static void __exit jr_driver_exit(void)
575 {
576 	platform_driver_unregister(&caam_jr_driver);
577 }
578 
579 module_init(jr_driver_init);
580 module_exit(jr_driver_exit);
581 
582 MODULE_LICENSE("GPL");
583 MODULE_DESCRIPTION("FSL CAAM JR request backend");
584 MODULE_AUTHOR("Freescale Semiconductor - NMG/STC");
585