xref: /openbmc/linux/drivers/iommu/msm_iommu.c (revision 05aed9412b0bd0d9a985d94010c42ff0a5c6cc29)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
3  *
4  * Author: Stepan Moskovchenko <stepanm@codeaurora.org>
5  */
6 
7 #define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
8 #include <linux/kernel.h>
9 #include <linux/init.h>
10 #include <linux/platform_device.h>
11 #include <linux/errno.h>
12 #include <linux/io.h>
13 #include <linux/io-pgtable.h>
14 #include <linux/interrupt.h>
15 #include <linux/list.h>
16 #include <linux/spinlock.h>
17 #include <linux/slab.h>
18 #include <linux/iommu.h>
19 #include <linux/clk.h>
20 #include <linux/err.h>
21 #include <linux/of_iommu.h>
22 
23 #include <asm/cacheflush.h>
24 #include <linux/sizes.h>
25 
26 #include "msm_iommu_hw-8xxx.h"
27 #include "msm_iommu.h"
28 
29 #define MRC(reg, processor, op1, crn, crm, op2)				\
30 __asm__ __volatile__ (							\
31 "   mrc   "   #processor "," #op1 ", %0,"  #crn "," #crm "," #op2 "\n"  \
32 : "=r" (reg))
33 
34 /* bitmap of the page sizes currently supported */
35 #define MSM_IOMMU_PGSIZES	(SZ_4K | SZ_64K | SZ_1M | SZ_16M)
36 
37 DEFINE_SPINLOCK(msm_iommu_lock);
38 static LIST_HEAD(qcom_iommu_devices);
39 static struct iommu_ops msm_iommu_ops;
40 
41 struct msm_priv {
42 	struct list_head list_attached;
43 	struct iommu_domain domain;
44 	struct io_pgtable_cfg	cfg;
45 	struct io_pgtable_ops	*iop;
46 	struct device		*dev;
47 	spinlock_t		pgtlock; /* pagetable lock */
48 };
49 
50 static struct msm_priv *to_msm_priv(struct iommu_domain *dom)
51 {
52 	return container_of(dom, struct msm_priv, domain);
53 }
54 
55 static int __enable_clocks(struct msm_iommu_dev *iommu)
56 {
57 	int ret;
58 
59 	ret = clk_enable(iommu->pclk);
60 	if (ret)
61 		goto fail;
62 
63 	if (iommu->clk) {
64 		ret = clk_enable(iommu->clk);
65 		if (ret)
66 			clk_disable(iommu->pclk);
67 	}
68 fail:
69 	return ret;
70 }
71 
72 static void __disable_clocks(struct msm_iommu_dev *iommu)
73 {
74 	if (iommu->clk)
75 		clk_disable(iommu->clk);
76 	clk_disable(iommu->pclk);
77 }
78 
79 static void msm_iommu_reset(void __iomem *base, int ncb)
80 {
81 	int ctx;
82 
83 	SET_RPUE(base, 0);
84 	SET_RPUEIE(base, 0);
85 	SET_ESRRESTORE(base, 0);
86 	SET_TBE(base, 0);
87 	SET_CR(base, 0);
88 	SET_SPDMBE(base, 0);
89 	SET_TESTBUSCR(base, 0);
90 	SET_TLBRSW(base, 0);
91 	SET_GLOBAL_TLBIALL(base, 0);
92 	SET_RPU_ACR(base, 0);
93 	SET_TLBLKCRWE(base, 1);
94 
95 	for (ctx = 0; ctx < ncb; ctx++) {
96 		SET_BPRCOSH(base, ctx, 0);
97 		SET_BPRCISH(base, ctx, 0);
98 		SET_BPRCNSH(base, ctx, 0);
99 		SET_BPSHCFG(base, ctx, 0);
100 		SET_BPMTCFG(base, ctx, 0);
101 		SET_ACTLR(base, ctx, 0);
102 		SET_SCTLR(base, ctx, 0);
103 		SET_FSRRESTORE(base, ctx, 0);
104 		SET_TTBR0(base, ctx, 0);
105 		SET_TTBR1(base, ctx, 0);
106 		SET_TTBCR(base, ctx, 0);
107 		SET_BFBCR(base, ctx, 0);
108 		SET_PAR(base, ctx, 0);
109 		SET_FAR(base, ctx, 0);
110 		SET_CTX_TLBIALL(base, ctx, 0);
111 		SET_TLBFLPTER(base, ctx, 0);
112 		SET_TLBSLPTER(base, ctx, 0);
113 		SET_TLBLKCR(base, ctx, 0);
114 		SET_CONTEXTIDR(base, ctx, 0);
115 	}
116 }
117 
118 static void __flush_iotlb(void *cookie)
119 {
120 	struct msm_priv *priv = cookie;
121 	struct msm_iommu_dev *iommu = NULL;
122 	struct msm_iommu_ctx_dev *master;
123 	int ret = 0;
124 
125 	list_for_each_entry(iommu, &priv->list_attached, dom_node) {
126 		ret = __enable_clocks(iommu);
127 		if (ret)
128 			goto fail;
129 
130 		list_for_each_entry(master, &iommu->ctx_list, list)
131 			SET_CTX_TLBIALL(iommu->base, master->num, 0);
132 
133 		__disable_clocks(iommu);
134 	}
135 fail:
136 	return;
137 }
138 
139 static void __flush_iotlb_range(unsigned long iova, size_t size,
140 				size_t granule, bool leaf, void *cookie)
141 {
142 	struct msm_priv *priv = cookie;
143 	struct msm_iommu_dev *iommu = NULL;
144 	struct msm_iommu_ctx_dev *master;
145 	int ret = 0;
146 	int temp_size;
147 
148 	list_for_each_entry(iommu, &priv->list_attached, dom_node) {
149 		ret = __enable_clocks(iommu);
150 		if (ret)
151 			goto fail;
152 
153 		list_for_each_entry(master, &iommu->ctx_list, list) {
154 			temp_size = size;
155 			do {
156 				iova &= TLBIVA_VA;
157 				iova |= GET_CONTEXTIDR_ASID(iommu->base,
158 							    master->num);
159 				SET_TLBIVA(iommu->base, master->num, iova);
160 				iova += granule;
161 			} while (temp_size -= granule);
162 		}
163 
164 		__disable_clocks(iommu);
165 	}
166 
167 fail:
168 	return;
169 }
170 
171 static void __flush_iotlb_sync(void *cookie)
172 {
173 	/*
174 	 * Nothing is needed here, the barrier to guarantee
175 	 * completion of the tlb sync operation is implicitly
176 	 * taken care when the iommu client does a writel before
177 	 * kick starting the other master.
178 	 */
179 }
180 
181 static void __flush_iotlb_walk(unsigned long iova, size_t size,
182 			       size_t granule, void *cookie)
183 {
184 	__flush_iotlb_range(iova, size, granule, false, cookie);
185 	__flush_iotlb_sync(cookie);
186 }
187 
188 static void __flush_iotlb_leaf(unsigned long iova, size_t size,
189 			       size_t granule, void *cookie)
190 {
191 	__flush_iotlb_range(iova, size, granule, true, cookie);
192 	__flush_iotlb_sync(cookie);
193 }
194 
195 static const struct iommu_flush_ops msm_iommu_flush_ops = {
196 	.tlb_flush_all = __flush_iotlb,
197 	.tlb_flush_walk = __flush_iotlb_walk,
198 	.tlb_flush_leaf = __flush_iotlb_leaf,
199 	.tlb_add_flush = __flush_iotlb_range,
200 	.tlb_sync = __flush_iotlb_sync,
201 };
202 
203 static int msm_iommu_alloc_ctx(unsigned long *map, int start, int end)
204 {
205 	int idx;
206 
207 	do {
208 		idx = find_next_zero_bit(map, end, start);
209 		if (idx == end)
210 			return -ENOSPC;
211 	} while (test_and_set_bit(idx, map));
212 
213 	return idx;
214 }
215 
216 static void msm_iommu_free_ctx(unsigned long *map, int idx)
217 {
218 	clear_bit(idx, map);
219 }
220 
221 static void config_mids(struct msm_iommu_dev *iommu,
222 			struct msm_iommu_ctx_dev *master)
223 {
224 	int mid, ctx, i;
225 
226 	for (i = 0; i < master->num_mids; i++) {
227 		mid = master->mids[i];
228 		ctx = master->num;
229 
230 		SET_M2VCBR_N(iommu->base, mid, 0);
231 		SET_CBACR_N(iommu->base, ctx, 0);
232 
233 		/* Set VMID = 0 */
234 		SET_VMID(iommu->base, mid, 0);
235 
236 		/* Set the context number for that MID to this context */
237 		SET_CBNDX(iommu->base, mid, ctx);
238 
239 		/* Set MID associated with this context bank to 0*/
240 		SET_CBVMID(iommu->base, ctx, 0);
241 
242 		/* Set the ASID for TLB tagging for this context */
243 		SET_CONTEXTIDR_ASID(iommu->base, ctx, ctx);
244 
245 		/* Set security bit override to be Non-secure */
246 		SET_NSCFG(iommu->base, mid, 3);
247 	}
248 }
249 
250 static void __reset_context(void __iomem *base, int ctx)
251 {
252 	SET_BPRCOSH(base, ctx, 0);
253 	SET_BPRCISH(base, ctx, 0);
254 	SET_BPRCNSH(base, ctx, 0);
255 	SET_BPSHCFG(base, ctx, 0);
256 	SET_BPMTCFG(base, ctx, 0);
257 	SET_ACTLR(base, ctx, 0);
258 	SET_SCTLR(base, ctx, 0);
259 	SET_FSRRESTORE(base, ctx, 0);
260 	SET_TTBR0(base, ctx, 0);
261 	SET_TTBR1(base, ctx, 0);
262 	SET_TTBCR(base, ctx, 0);
263 	SET_BFBCR(base, ctx, 0);
264 	SET_PAR(base, ctx, 0);
265 	SET_FAR(base, ctx, 0);
266 	SET_CTX_TLBIALL(base, ctx, 0);
267 	SET_TLBFLPTER(base, ctx, 0);
268 	SET_TLBSLPTER(base, ctx, 0);
269 	SET_TLBLKCR(base, ctx, 0);
270 }
271 
272 static void __program_context(void __iomem *base, int ctx,
273 			      struct msm_priv *priv)
274 {
275 	__reset_context(base, ctx);
276 
277 	/* Turn on TEX Remap */
278 	SET_TRE(base, ctx, 1);
279 	SET_AFE(base, ctx, 1);
280 
281 	/* Set up HTW mode */
282 	/* TLB miss configuration: perform HTW on miss */
283 	SET_TLBMCFG(base, ctx, 0x3);
284 
285 	/* V2P configuration: HTW for access */
286 	SET_V2PCFG(base, ctx, 0x3);
287 
288 	SET_TTBCR(base, ctx, priv->cfg.arm_v7s_cfg.tcr);
289 	SET_TTBR0(base, ctx, priv->cfg.arm_v7s_cfg.ttbr[0]);
290 	SET_TTBR1(base, ctx, priv->cfg.arm_v7s_cfg.ttbr[1]);
291 
292 	/* Set prrr and nmrr */
293 	SET_PRRR(base, ctx, priv->cfg.arm_v7s_cfg.prrr);
294 	SET_NMRR(base, ctx, priv->cfg.arm_v7s_cfg.nmrr);
295 
296 	/* Invalidate the TLB for this context */
297 	SET_CTX_TLBIALL(base, ctx, 0);
298 
299 	/* Set interrupt number to "secure" interrupt */
300 	SET_IRPTNDX(base, ctx, 0);
301 
302 	/* Enable context fault interrupt */
303 	SET_CFEIE(base, ctx, 1);
304 
305 	/* Stall access on a context fault and let the handler deal with it */
306 	SET_CFCFG(base, ctx, 1);
307 
308 	/* Redirect all cacheable requests to L2 slave port. */
309 	SET_RCISH(base, ctx, 1);
310 	SET_RCOSH(base, ctx, 1);
311 	SET_RCNSH(base, ctx, 1);
312 
313 	/* Turn on BFB prefetch */
314 	SET_BFBDFE(base, ctx, 1);
315 
316 	/* Enable the MMU */
317 	SET_M(base, ctx, 1);
318 }
319 
320 static struct iommu_domain *msm_iommu_domain_alloc(unsigned type)
321 {
322 	struct msm_priv *priv;
323 
324 	if (type != IOMMU_DOMAIN_UNMANAGED)
325 		return NULL;
326 
327 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
328 	if (!priv)
329 		goto fail_nomem;
330 
331 	INIT_LIST_HEAD(&priv->list_attached);
332 
333 	priv->domain.geometry.aperture_start = 0;
334 	priv->domain.geometry.aperture_end   = (1ULL << 32) - 1;
335 	priv->domain.geometry.force_aperture = true;
336 
337 	return &priv->domain;
338 
339 fail_nomem:
340 	kfree(priv);
341 	return NULL;
342 }
343 
344 static void msm_iommu_domain_free(struct iommu_domain *domain)
345 {
346 	struct msm_priv *priv;
347 	unsigned long flags;
348 
349 	spin_lock_irqsave(&msm_iommu_lock, flags);
350 	priv = to_msm_priv(domain);
351 	kfree(priv);
352 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
353 }
354 
355 static int msm_iommu_domain_config(struct msm_priv *priv)
356 {
357 	spin_lock_init(&priv->pgtlock);
358 
359 	priv->cfg = (struct io_pgtable_cfg) {
360 		.quirks = IO_PGTABLE_QUIRK_TLBI_ON_MAP,
361 		.pgsize_bitmap = msm_iommu_ops.pgsize_bitmap,
362 		.ias = 32,
363 		.oas = 32,
364 		.tlb = &msm_iommu_flush_ops,
365 		.iommu_dev = priv->dev,
366 	};
367 
368 	priv->iop = alloc_io_pgtable_ops(ARM_V7S, &priv->cfg, priv);
369 	if (!priv->iop) {
370 		dev_err(priv->dev, "Failed to allocate pgtable\n");
371 		return -EINVAL;
372 	}
373 
374 	msm_iommu_ops.pgsize_bitmap = priv->cfg.pgsize_bitmap;
375 
376 	return 0;
377 }
378 
379 /* Must be called under msm_iommu_lock */
380 static struct msm_iommu_dev *find_iommu_for_dev(struct device *dev)
381 {
382 	struct msm_iommu_dev *iommu, *ret = NULL;
383 	struct msm_iommu_ctx_dev *master;
384 
385 	list_for_each_entry(iommu, &qcom_iommu_devices, dev_node) {
386 		master = list_first_entry(&iommu->ctx_list,
387 					  struct msm_iommu_ctx_dev,
388 					  list);
389 		if (master->of_node == dev->of_node) {
390 			ret = iommu;
391 			break;
392 		}
393 	}
394 
395 	return ret;
396 }
397 
398 static int msm_iommu_add_device(struct device *dev)
399 {
400 	struct msm_iommu_dev *iommu;
401 	struct iommu_group *group;
402 	unsigned long flags;
403 
404 	spin_lock_irqsave(&msm_iommu_lock, flags);
405 	iommu = find_iommu_for_dev(dev);
406 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
407 
408 	if (iommu)
409 		iommu_device_link(&iommu->iommu, dev);
410 	else
411 		return -ENODEV;
412 
413 	group = iommu_group_get_for_dev(dev);
414 	if (IS_ERR(group))
415 		return PTR_ERR(group);
416 
417 	iommu_group_put(group);
418 
419 	return 0;
420 }
421 
422 static void msm_iommu_remove_device(struct device *dev)
423 {
424 	struct msm_iommu_dev *iommu;
425 	unsigned long flags;
426 
427 	spin_lock_irqsave(&msm_iommu_lock, flags);
428 	iommu = find_iommu_for_dev(dev);
429 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
430 
431 	if (iommu)
432 		iommu_device_unlink(&iommu->iommu, dev);
433 
434 	iommu_group_remove_device(dev);
435 }
436 
437 static int msm_iommu_attach_dev(struct iommu_domain *domain, struct device *dev)
438 {
439 	int ret = 0;
440 	unsigned long flags;
441 	struct msm_iommu_dev *iommu;
442 	struct msm_priv *priv = to_msm_priv(domain);
443 	struct msm_iommu_ctx_dev *master;
444 
445 	priv->dev = dev;
446 	msm_iommu_domain_config(priv);
447 
448 	spin_lock_irqsave(&msm_iommu_lock, flags);
449 	list_for_each_entry(iommu, &qcom_iommu_devices, dev_node) {
450 		master = list_first_entry(&iommu->ctx_list,
451 					  struct msm_iommu_ctx_dev,
452 					  list);
453 		if (master->of_node == dev->of_node) {
454 			ret = __enable_clocks(iommu);
455 			if (ret)
456 				goto fail;
457 
458 			list_for_each_entry(master, &iommu->ctx_list, list) {
459 				if (master->num) {
460 					dev_err(dev, "domain already attached");
461 					ret = -EEXIST;
462 					goto fail;
463 				}
464 				master->num =
465 					msm_iommu_alloc_ctx(iommu->context_map,
466 							    0, iommu->ncb);
467 				if (IS_ERR_VALUE(master->num)) {
468 					ret = -ENODEV;
469 					goto fail;
470 				}
471 				config_mids(iommu, master);
472 				__program_context(iommu->base, master->num,
473 						  priv);
474 			}
475 			__disable_clocks(iommu);
476 			list_add(&iommu->dom_node, &priv->list_attached);
477 		}
478 	}
479 
480 fail:
481 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
482 
483 	return ret;
484 }
485 
486 static void msm_iommu_detach_dev(struct iommu_domain *domain,
487 				 struct device *dev)
488 {
489 	struct msm_priv *priv = to_msm_priv(domain);
490 	unsigned long flags;
491 	struct msm_iommu_dev *iommu;
492 	struct msm_iommu_ctx_dev *master;
493 	int ret;
494 
495 	free_io_pgtable_ops(priv->iop);
496 
497 	spin_lock_irqsave(&msm_iommu_lock, flags);
498 	list_for_each_entry(iommu, &priv->list_attached, dom_node) {
499 		ret = __enable_clocks(iommu);
500 		if (ret)
501 			goto fail;
502 
503 		list_for_each_entry(master, &iommu->ctx_list, list) {
504 			msm_iommu_free_ctx(iommu->context_map, master->num);
505 			__reset_context(iommu->base, master->num);
506 		}
507 		__disable_clocks(iommu);
508 	}
509 fail:
510 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
511 }
512 
513 static int msm_iommu_map(struct iommu_domain *domain, unsigned long iova,
514 			 phys_addr_t pa, size_t len, int prot)
515 {
516 	struct msm_priv *priv = to_msm_priv(domain);
517 	unsigned long flags;
518 	int ret;
519 
520 	spin_lock_irqsave(&priv->pgtlock, flags);
521 	ret = priv->iop->map(priv->iop, iova, pa, len, prot);
522 	spin_unlock_irqrestore(&priv->pgtlock, flags);
523 
524 	return ret;
525 }
526 
527 static size_t msm_iommu_unmap(struct iommu_domain *domain, unsigned long iova,
528 			      size_t len, struct iommu_iotlb_gather *gather)
529 {
530 	struct msm_priv *priv = to_msm_priv(domain);
531 	unsigned long flags;
532 
533 	spin_lock_irqsave(&priv->pgtlock, flags);
534 	len = priv->iop->unmap(priv->iop, iova, len);
535 	spin_unlock_irqrestore(&priv->pgtlock, flags);
536 
537 	return len;
538 }
539 
540 static phys_addr_t msm_iommu_iova_to_phys(struct iommu_domain *domain,
541 					  dma_addr_t va)
542 {
543 	struct msm_priv *priv;
544 	struct msm_iommu_dev *iommu;
545 	struct msm_iommu_ctx_dev *master;
546 	unsigned int par;
547 	unsigned long flags;
548 	phys_addr_t ret = 0;
549 
550 	spin_lock_irqsave(&msm_iommu_lock, flags);
551 
552 	priv = to_msm_priv(domain);
553 	iommu = list_first_entry(&priv->list_attached,
554 				 struct msm_iommu_dev, dom_node);
555 
556 	if (list_empty(&iommu->ctx_list))
557 		goto fail;
558 
559 	master = list_first_entry(&iommu->ctx_list,
560 				  struct msm_iommu_ctx_dev, list);
561 	if (!master)
562 		goto fail;
563 
564 	ret = __enable_clocks(iommu);
565 	if (ret)
566 		goto fail;
567 
568 	/* Invalidate context TLB */
569 	SET_CTX_TLBIALL(iommu->base, master->num, 0);
570 	SET_V2PPR(iommu->base, master->num, va & V2Pxx_VA);
571 
572 	par = GET_PAR(iommu->base, master->num);
573 
574 	/* We are dealing with a supersection */
575 	if (GET_NOFAULT_SS(iommu->base, master->num))
576 		ret = (par & 0xFF000000) | (va & 0x00FFFFFF);
577 	else	/* Upper 20 bits from PAR, lower 12 from VA */
578 		ret = (par & 0xFFFFF000) | (va & 0x00000FFF);
579 
580 	if (GET_FAULT(iommu->base, master->num))
581 		ret = 0;
582 
583 	__disable_clocks(iommu);
584 fail:
585 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
586 	return ret;
587 }
588 
589 static bool msm_iommu_capable(enum iommu_cap cap)
590 {
591 	return false;
592 }
593 
594 static void print_ctx_regs(void __iomem *base, int ctx)
595 {
596 	unsigned int fsr = GET_FSR(base, ctx);
597 	pr_err("FAR    = %08x    PAR    = %08x\n",
598 	       GET_FAR(base, ctx), GET_PAR(base, ctx));
599 	pr_err("FSR    = %08x [%s%s%s%s%s%s%s%s%s%s]\n", fsr,
600 			(fsr & 0x02) ? "TF " : "",
601 			(fsr & 0x04) ? "AFF " : "",
602 			(fsr & 0x08) ? "APF " : "",
603 			(fsr & 0x10) ? "TLBMF " : "",
604 			(fsr & 0x20) ? "HTWDEEF " : "",
605 			(fsr & 0x40) ? "HTWSEEF " : "",
606 			(fsr & 0x80) ? "MHF " : "",
607 			(fsr & 0x10000) ? "SL " : "",
608 			(fsr & 0x40000000) ? "SS " : "",
609 			(fsr & 0x80000000) ? "MULTI " : "");
610 
611 	pr_err("FSYNR0 = %08x    FSYNR1 = %08x\n",
612 	       GET_FSYNR0(base, ctx), GET_FSYNR1(base, ctx));
613 	pr_err("TTBR0  = %08x    TTBR1  = %08x\n",
614 	       GET_TTBR0(base, ctx), GET_TTBR1(base, ctx));
615 	pr_err("SCTLR  = %08x    ACTLR  = %08x\n",
616 	       GET_SCTLR(base, ctx), GET_ACTLR(base, ctx));
617 }
618 
619 static void insert_iommu_master(struct device *dev,
620 				struct msm_iommu_dev **iommu,
621 				struct of_phandle_args *spec)
622 {
623 	struct msm_iommu_ctx_dev *master = dev->archdata.iommu;
624 	int sid;
625 
626 	if (list_empty(&(*iommu)->ctx_list)) {
627 		master = kzalloc(sizeof(*master), GFP_ATOMIC);
628 		master->of_node = dev->of_node;
629 		list_add(&master->list, &(*iommu)->ctx_list);
630 		dev->archdata.iommu = master;
631 	}
632 
633 	for (sid = 0; sid < master->num_mids; sid++)
634 		if (master->mids[sid] == spec->args[0]) {
635 			dev_warn(dev, "Stream ID 0x%hx repeated; ignoring\n",
636 				 sid);
637 			return;
638 		}
639 
640 	master->mids[master->num_mids++] = spec->args[0];
641 }
642 
643 static int qcom_iommu_of_xlate(struct device *dev,
644 			       struct of_phandle_args *spec)
645 {
646 	struct msm_iommu_dev *iommu;
647 	unsigned long flags;
648 	int ret = 0;
649 
650 	spin_lock_irqsave(&msm_iommu_lock, flags);
651 	list_for_each_entry(iommu, &qcom_iommu_devices, dev_node)
652 		if (iommu->dev->of_node == spec->np)
653 			break;
654 
655 	if (!iommu || iommu->dev->of_node != spec->np) {
656 		ret = -ENODEV;
657 		goto fail;
658 	}
659 
660 	insert_iommu_master(dev, &iommu, spec);
661 fail:
662 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
663 
664 	return ret;
665 }
666 
667 irqreturn_t msm_iommu_fault_handler(int irq, void *dev_id)
668 {
669 	struct msm_iommu_dev *iommu = dev_id;
670 	unsigned int fsr;
671 	int i, ret;
672 
673 	spin_lock(&msm_iommu_lock);
674 
675 	if (!iommu) {
676 		pr_err("Invalid device ID in context interrupt handler\n");
677 		goto fail;
678 	}
679 
680 	pr_err("Unexpected IOMMU page fault!\n");
681 	pr_err("base = %08x\n", (unsigned int)iommu->base);
682 
683 	ret = __enable_clocks(iommu);
684 	if (ret)
685 		goto fail;
686 
687 	for (i = 0; i < iommu->ncb; i++) {
688 		fsr = GET_FSR(iommu->base, i);
689 		if (fsr) {
690 			pr_err("Fault occurred in context %d.\n", i);
691 			pr_err("Interesting registers:\n");
692 			print_ctx_regs(iommu->base, i);
693 			SET_FSR(iommu->base, i, 0x4000000F);
694 		}
695 	}
696 	__disable_clocks(iommu);
697 fail:
698 	spin_unlock(&msm_iommu_lock);
699 	return 0;
700 }
701 
702 static struct iommu_ops msm_iommu_ops = {
703 	.capable = msm_iommu_capable,
704 	.domain_alloc = msm_iommu_domain_alloc,
705 	.domain_free = msm_iommu_domain_free,
706 	.attach_dev = msm_iommu_attach_dev,
707 	.detach_dev = msm_iommu_detach_dev,
708 	.map = msm_iommu_map,
709 	.unmap = msm_iommu_unmap,
710 	.iova_to_phys = msm_iommu_iova_to_phys,
711 	.add_device = msm_iommu_add_device,
712 	.remove_device = msm_iommu_remove_device,
713 	.device_group = generic_device_group,
714 	.pgsize_bitmap = MSM_IOMMU_PGSIZES,
715 	.of_xlate = qcom_iommu_of_xlate,
716 };
717 
718 static int msm_iommu_probe(struct platform_device *pdev)
719 {
720 	struct resource *r;
721 	resource_size_t ioaddr;
722 	struct msm_iommu_dev *iommu;
723 	int ret, par, val;
724 
725 	iommu = devm_kzalloc(&pdev->dev, sizeof(*iommu), GFP_KERNEL);
726 	if (!iommu)
727 		return -ENODEV;
728 
729 	iommu->dev = &pdev->dev;
730 	INIT_LIST_HEAD(&iommu->ctx_list);
731 
732 	iommu->pclk = devm_clk_get(iommu->dev, "smmu_pclk");
733 	if (IS_ERR(iommu->pclk)) {
734 		dev_err(iommu->dev, "could not get smmu_pclk\n");
735 		return PTR_ERR(iommu->pclk);
736 	}
737 
738 	ret = clk_prepare(iommu->pclk);
739 	if (ret) {
740 		dev_err(iommu->dev, "could not prepare smmu_pclk\n");
741 		return ret;
742 	}
743 
744 	iommu->clk = devm_clk_get(iommu->dev, "iommu_clk");
745 	if (IS_ERR(iommu->clk)) {
746 		dev_err(iommu->dev, "could not get iommu_clk\n");
747 		clk_unprepare(iommu->pclk);
748 		return PTR_ERR(iommu->clk);
749 	}
750 
751 	ret = clk_prepare(iommu->clk);
752 	if (ret) {
753 		dev_err(iommu->dev, "could not prepare iommu_clk\n");
754 		clk_unprepare(iommu->pclk);
755 		return ret;
756 	}
757 
758 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
759 	iommu->base = devm_ioremap_resource(iommu->dev, r);
760 	if (IS_ERR(iommu->base)) {
761 		dev_err(iommu->dev, "could not get iommu base\n");
762 		ret = PTR_ERR(iommu->base);
763 		goto fail;
764 	}
765 	ioaddr = r->start;
766 
767 	iommu->irq = platform_get_irq(pdev, 0);
768 	if (iommu->irq < 0) {
769 		dev_err(iommu->dev, "could not get iommu irq\n");
770 		ret = -ENODEV;
771 		goto fail;
772 	}
773 
774 	ret = of_property_read_u32(iommu->dev->of_node, "qcom,ncb", &val);
775 	if (ret) {
776 		dev_err(iommu->dev, "could not get ncb\n");
777 		goto fail;
778 	}
779 	iommu->ncb = val;
780 
781 	msm_iommu_reset(iommu->base, iommu->ncb);
782 	SET_M(iommu->base, 0, 1);
783 	SET_PAR(iommu->base, 0, 0);
784 	SET_V2PCFG(iommu->base, 0, 1);
785 	SET_V2PPR(iommu->base, 0, 0);
786 	par = GET_PAR(iommu->base, 0);
787 	SET_V2PCFG(iommu->base, 0, 0);
788 	SET_M(iommu->base, 0, 0);
789 
790 	if (!par) {
791 		pr_err("Invalid PAR value detected\n");
792 		ret = -ENODEV;
793 		goto fail;
794 	}
795 
796 	ret = devm_request_threaded_irq(iommu->dev, iommu->irq, NULL,
797 					msm_iommu_fault_handler,
798 					IRQF_ONESHOT | IRQF_SHARED,
799 					"msm_iommu_secure_irpt_handler",
800 					iommu);
801 	if (ret) {
802 		pr_err("Request IRQ %d failed with ret=%d\n", iommu->irq, ret);
803 		goto fail;
804 	}
805 
806 	list_add(&iommu->dev_node, &qcom_iommu_devices);
807 
808 	ret = iommu_device_sysfs_add(&iommu->iommu, iommu->dev, NULL,
809 				     "msm-smmu.%pa", &ioaddr);
810 	if (ret) {
811 		pr_err("Could not add msm-smmu at %pa to sysfs\n", &ioaddr);
812 		goto fail;
813 	}
814 
815 	iommu_device_set_ops(&iommu->iommu, &msm_iommu_ops);
816 	iommu_device_set_fwnode(&iommu->iommu, &pdev->dev.of_node->fwnode);
817 
818 	ret = iommu_device_register(&iommu->iommu);
819 	if (ret) {
820 		pr_err("Could not register msm-smmu at %pa\n", &ioaddr);
821 		goto fail;
822 	}
823 
824 	bus_set_iommu(&platform_bus_type, &msm_iommu_ops);
825 
826 	pr_info("device mapped at %p, irq %d with %d ctx banks\n",
827 		iommu->base, iommu->irq, iommu->ncb);
828 
829 	return ret;
830 fail:
831 	clk_unprepare(iommu->clk);
832 	clk_unprepare(iommu->pclk);
833 	return ret;
834 }
835 
836 static const struct of_device_id msm_iommu_dt_match[] = {
837 	{ .compatible = "qcom,apq8064-iommu" },
838 	{}
839 };
840 
841 static int msm_iommu_remove(struct platform_device *pdev)
842 {
843 	struct msm_iommu_dev *iommu = platform_get_drvdata(pdev);
844 
845 	clk_unprepare(iommu->clk);
846 	clk_unprepare(iommu->pclk);
847 	return 0;
848 }
849 
850 static struct platform_driver msm_iommu_driver = {
851 	.driver = {
852 		.name	= "msm_iommu",
853 		.of_match_table = msm_iommu_dt_match,
854 	},
855 	.probe		= msm_iommu_probe,
856 	.remove		= msm_iommu_remove,
857 };
858 
859 static int __init msm_iommu_driver_init(void)
860 {
861 	int ret;
862 
863 	ret = platform_driver_register(&msm_iommu_driver);
864 	if (ret != 0)
865 		pr_err("Failed to register IOMMU driver\n");
866 
867 	return ret;
868 }
869 subsys_initcall(msm_iommu_driver_init);
870 
871