xref: /openbmc/linux/drivers/iommu/msm_iommu.c (revision dd1fc3c5)
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 static 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_walk(unsigned long iova, size_t size,
172 			       size_t granule, void *cookie)
173 {
174 	__flush_iotlb_range(iova, size, granule, false, cookie);
175 }
176 
177 static void __flush_iotlb_page(struct iommu_iotlb_gather *gather,
178 			       unsigned long iova, size_t granule, void *cookie)
179 {
180 	__flush_iotlb_range(iova, granule, granule, true, cookie);
181 }
182 
183 static const struct iommu_flush_ops msm_iommu_flush_ops = {
184 	.tlb_flush_all = __flush_iotlb,
185 	.tlb_flush_walk = __flush_iotlb_walk,
186 	.tlb_add_page = __flush_iotlb_page,
187 };
188 
189 static int msm_iommu_alloc_ctx(unsigned long *map, int start, int end)
190 {
191 	int idx;
192 
193 	do {
194 		idx = find_next_zero_bit(map, end, start);
195 		if (idx == end)
196 			return -ENOSPC;
197 	} while (test_and_set_bit(idx, map));
198 
199 	return idx;
200 }
201 
202 static void msm_iommu_free_ctx(unsigned long *map, int idx)
203 {
204 	clear_bit(idx, map);
205 }
206 
207 static void config_mids(struct msm_iommu_dev *iommu,
208 			struct msm_iommu_ctx_dev *master)
209 {
210 	int mid, ctx, i;
211 
212 	for (i = 0; i < master->num_mids; i++) {
213 		mid = master->mids[i];
214 		ctx = master->num;
215 
216 		SET_M2VCBR_N(iommu->base, mid, 0);
217 		SET_CBACR_N(iommu->base, ctx, 0);
218 
219 		/* Set VMID = 0 */
220 		SET_VMID(iommu->base, mid, 0);
221 
222 		/* Set the context number for that MID to this context */
223 		SET_CBNDX(iommu->base, mid, ctx);
224 
225 		/* Set MID associated with this context bank to 0*/
226 		SET_CBVMID(iommu->base, ctx, 0);
227 
228 		/* Set the ASID for TLB tagging for this context */
229 		SET_CONTEXTIDR_ASID(iommu->base, ctx, ctx);
230 
231 		/* Set security bit override to be Non-secure */
232 		SET_NSCFG(iommu->base, mid, 3);
233 	}
234 }
235 
236 static void __reset_context(void __iomem *base, int ctx)
237 {
238 	SET_BPRCOSH(base, ctx, 0);
239 	SET_BPRCISH(base, ctx, 0);
240 	SET_BPRCNSH(base, ctx, 0);
241 	SET_BPSHCFG(base, ctx, 0);
242 	SET_BPMTCFG(base, ctx, 0);
243 	SET_ACTLR(base, ctx, 0);
244 	SET_SCTLR(base, ctx, 0);
245 	SET_FSRRESTORE(base, ctx, 0);
246 	SET_TTBR0(base, ctx, 0);
247 	SET_TTBR1(base, ctx, 0);
248 	SET_TTBCR(base, ctx, 0);
249 	SET_BFBCR(base, ctx, 0);
250 	SET_PAR(base, ctx, 0);
251 	SET_FAR(base, ctx, 0);
252 	SET_CTX_TLBIALL(base, ctx, 0);
253 	SET_TLBFLPTER(base, ctx, 0);
254 	SET_TLBSLPTER(base, ctx, 0);
255 	SET_TLBLKCR(base, ctx, 0);
256 }
257 
258 static void __program_context(void __iomem *base, int ctx,
259 			      struct msm_priv *priv)
260 {
261 	__reset_context(base, ctx);
262 
263 	/* Turn on TEX Remap */
264 	SET_TRE(base, ctx, 1);
265 	SET_AFE(base, ctx, 1);
266 
267 	/* Set up HTW mode */
268 	/* TLB miss configuration: perform HTW on miss */
269 	SET_TLBMCFG(base, ctx, 0x3);
270 
271 	/* V2P configuration: HTW for access */
272 	SET_V2PCFG(base, ctx, 0x3);
273 
274 	SET_TTBCR(base, ctx, priv->cfg.arm_v7s_cfg.tcr);
275 	SET_TTBR0(base, ctx, priv->cfg.arm_v7s_cfg.ttbr);
276 	SET_TTBR1(base, ctx, 0);
277 
278 	/* Set prrr and nmrr */
279 	SET_PRRR(base, ctx, priv->cfg.arm_v7s_cfg.prrr);
280 	SET_NMRR(base, ctx, priv->cfg.arm_v7s_cfg.nmrr);
281 
282 	/* Invalidate the TLB for this context */
283 	SET_CTX_TLBIALL(base, ctx, 0);
284 
285 	/* Set interrupt number to "secure" interrupt */
286 	SET_IRPTNDX(base, ctx, 0);
287 
288 	/* Enable context fault interrupt */
289 	SET_CFEIE(base, ctx, 1);
290 
291 	/* Stall access on a context fault and let the handler deal with it */
292 	SET_CFCFG(base, ctx, 1);
293 
294 	/* Redirect all cacheable requests to L2 slave port. */
295 	SET_RCISH(base, ctx, 1);
296 	SET_RCOSH(base, ctx, 1);
297 	SET_RCNSH(base, ctx, 1);
298 
299 	/* Turn on BFB prefetch */
300 	SET_BFBDFE(base, ctx, 1);
301 
302 	/* Enable the MMU */
303 	SET_M(base, ctx, 1);
304 }
305 
306 static struct iommu_domain *msm_iommu_domain_alloc(unsigned type)
307 {
308 	struct msm_priv *priv;
309 
310 	if (type != IOMMU_DOMAIN_UNMANAGED)
311 		return NULL;
312 
313 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
314 	if (!priv)
315 		goto fail_nomem;
316 
317 	INIT_LIST_HEAD(&priv->list_attached);
318 
319 	priv->domain.geometry.aperture_start = 0;
320 	priv->domain.geometry.aperture_end   = (1ULL << 32) - 1;
321 	priv->domain.geometry.force_aperture = true;
322 
323 	return &priv->domain;
324 
325 fail_nomem:
326 	kfree(priv);
327 	return NULL;
328 }
329 
330 static void msm_iommu_domain_free(struct iommu_domain *domain)
331 {
332 	struct msm_priv *priv;
333 	unsigned long flags;
334 
335 	spin_lock_irqsave(&msm_iommu_lock, flags);
336 	priv = to_msm_priv(domain);
337 	kfree(priv);
338 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
339 }
340 
341 static int msm_iommu_domain_config(struct msm_priv *priv)
342 {
343 	spin_lock_init(&priv->pgtlock);
344 
345 	priv->cfg = (struct io_pgtable_cfg) {
346 		.pgsize_bitmap = msm_iommu_ops.pgsize_bitmap,
347 		.ias = 32,
348 		.oas = 32,
349 		.tlb = &msm_iommu_flush_ops,
350 		.iommu_dev = priv->dev,
351 	};
352 
353 	priv->iop = alloc_io_pgtable_ops(ARM_V7S, &priv->cfg, priv);
354 	if (!priv->iop) {
355 		dev_err(priv->dev, "Failed to allocate pgtable\n");
356 		return -EINVAL;
357 	}
358 
359 	msm_iommu_ops.pgsize_bitmap = priv->cfg.pgsize_bitmap;
360 
361 	return 0;
362 }
363 
364 /* Must be called under msm_iommu_lock */
365 static struct msm_iommu_dev *find_iommu_for_dev(struct device *dev)
366 {
367 	struct msm_iommu_dev *iommu, *ret = NULL;
368 	struct msm_iommu_ctx_dev *master;
369 
370 	list_for_each_entry(iommu, &qcom_iommu_devices, dev_node) {
371 		master = list_first_entry(&iommu->ctx_list,
372 					  struct msm_iommu_ctx_dev,
373 					  list);
374 		if (master->of_node == dev->of_node) {
375 			ret = iommu;
376 			break;
377 		}
378 	}
379 
380 	return ret;
381 }
382 
383 static struct iommu_device *msm_iommu_probe_device(struct device *dev)
384 {
385 	struct msm_iommu_dev *iommu;
386 	unsigned long flags;
387 
388 	spin_lock_irqsave(&msm_iommu_lock, flags);
389 	iommu = find_iommu_for_dev(dev);
390 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
391 
392 	if (!iommu)
393 		return ERR_PTR(-ENODEV);
394 
395 	return &iommu->iommu;
396 }
397 
398 static void msm_iommu_release_device(struct device *dev)
399 {
400 }
401 
402 static int msm_iommu_attach_dev(struct iommu_domain *domain, struct device *dev)
403 {
404 	int ret = 0;
405 	unsigned long flags;
406 	struct msm_iommu_dev *iommu;
407 	struct msm_priv *priv = to_msm_priv(domain);
408 	struct msm_iommu_ctx_dev *master;
409 
410 	priv->dev = dev;
411 	msm_iommu_domain_config(priv);
412 
413 	spin_lock_irqsave(&msm_iommu_lock, flags);
414 	list_for_each_entry(iommu, &qcom_iommu_devices, dev_node) {
415 		master = list_first_entry(&iommu->ctx_list,
416 					  struct msm_iommu_ctx_dev,
417 					  list);
418 		if (master->of_node == dev->of_node) {
419 			ret = __enable_clocks(iommu);
420 			if (ret)
421 				goto fail;
422 
423 			list_for_each_entry(master, &iommu->ctx_list, list) {
424 				if (master->num) {
425 					dev_err(dev, "domain already attached");
426 					ret = -EEXIST;
427 					goto fail;
428 				}
429 				master->num =
430 					msm_iommu_alloc_ctx(iommu->context_map,
431 							    0, iommu->ncb);
432 				if (IS_ERR_VALUE(master->num)) {
433 					ret = -ENODEV;
434 					goto fail;
435 				}
436 				config_mids(iommu, master);
437 				__program_context(iommu->base, master->num,
438 						  priv);
439 			}
440 			__disable_clocks(iommu);
441 			list_add(&iommu->dom_node, &priv->list_attached);
442 		}
443 	}
444 
445 fail:
446 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
447 
448 	return ret;
449 }
450 
451 static void msm_iommu_detach_dev(struct iommu_domain *domain,
452 				 struct device *dev)
453 {
454 	struct msm_priv *priv = to_msm_priv(domain);
455 	unsigned long flags;
456 	struct msm_iommu_dev *iommu;
457 	struct msm_iommu_ctx_dev *master;
458 	int ret;
459 
460 	free_io_pgtable_ops(priv->iop);
461 
462 	spin_lock_irqsave(&msm_iommu_lock, flags);
463 	list_for_each_entry(iommu, &priv->list_attached, dom_node) {
464 		ret = __enable_clocks(iommu);
465 		if (ret)
466 			goto fail;
467 
468 		list_for_each_entry(master, &iommu->ctx_list, list) {
469 			msm_iommu_free_ctx(iommu->context_map, master->num);
470 			__reset_context(iommu->base, master->num);
471 		}
472 		__disable_clocks(iommu);
473 	}
474 fail:
475 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
476 }
477 
478 static int msm_iommu_map(struct iommu_domain *domain, unsigned long iova,
479 			 phys_addr_t pa, size_t len, int prot, gfp_t gfp)
480 {
481 	struct msm_priv *priv = to_msm_priv(domain);
482 	unsigned long flags;
483 	int ret;
484 
485 	spin_lock_irqsave(&priv->pgtlock, flags);
486 	ret = priv->iop->map(priv->iop, iova, pa, len, prot, GFP_ATOMIC);
487 	spin_unlock_irqrestore(&priv->pgtlock, flags);
488 
489 	return ret;
490 }
491 
492 static void msm_iommu_sync_map(struct iommu_domain *domain, unsigned long iova,
493 			       size_t size)
494 {
495 	struct msm_priv *priv = to_msm_priv(domain);
496 
497 	__flush_iotlb_range(iova, size, SZ_4K, false, priv);
498 }
499 
500 static size_t msm_iommu_unmap(struct iommu_domain *domain, unsigned long iova,
501 			      size_t len, struct iommu_iotlb_gather *gather)
502 {
503 	struct msm_priv *priv = to_msm_priv(domain);
504 	unsigned long flags;
505 
506 	spin_lock_irqsave(&priv->pgtlock, flags);
507 	len = priv->iop->unmap(priv->iop, iova, len, gather);
508 	spin_unlock_irqrestore(&priv->pgtlock, flags);
509 
510 	return len;
511 }
512 
513 static phys_addr_t msm_iommu_iova_to_phys(struct iommu_domain *domain,
514 					  dma_addr_t va)
515 {
516 	struct msm_priv *priv;
517 	struct msm_iommu_dev *iommu;
518 	struct msm_iommu_ctx_dev *master;
519 	unsigned int par;
520 	unsigned long flags;
521 	phys_addr_t ret = 0;
522 
523 	spin_lock_irqsave(&msm_iommu_lock, flags);
524 
525 	priv = to_msm_priv(domain);
526 	iommu = list_first_entry(&priv->list_attached,
527 				 struct msm_iommu_dev, dom_node);
528 
529 	if (list_empty(&iommu->ctx_list))
530 		goto fail;
531 
532 	master = list_first_entry(&iommu->ctx_list,
533 				  struct msm_iommu_ctx_dev, list);
534 	if (!master)
535 		goto fail;
536 
537 	ret = __enable_clocks(iommu);
538 	if (ret)
539 		goto fail;
540 
541 	/* Invalidate context TLB */
542 	SET_CTX_TLBIALL(iommu->base, master->num, 0);
543 	SET_V2PPR(iommu->base, master->num, va & V2Pxx_VA);
544 
545 	par = GET_PAR(iommu->base, master->num);
546 
547 	/* We are dealing with a supersection */
548 	if (GET_NOFAULT_SS(iommu->base, master->num))
549 		ret = (par & 0xFF000000) | (va & 0x00FFFFFF);
550 	else	/* Upper 20 bits from PAR, lower 12 from VA */
551 		ret = (par & 0xFFFFF000) | (va & 0x00000FFF);
552 
553 	if (GET_FAULT(iommu->base, master->num))
554 		ret = 0;
555 
556 	__disable_clocks(iommu);
557 fail:
558 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
559 	return ret;
560 }
561 
562 static bool msm_iommu_capable(enum iommu_cap cap)
563 {
564 	return false;
565 }
566 
567 static void print_ctx_regs(void __iomem *base, int ctx)
568 {
569 	unsigned int fsr = GET_FSR(base, ctx);
570 	pr_err("FAR    = %08x    PAR    = %08x\n",
571 	       GET_FAR(base, ctx), GET_PAR(base, ctx));
572 	pr_err("FSR    = %08x [%s%s%s%s%s%s%s%s%s%s]\n", fsr,
573 			(fsr & 0x02) ? "TF " : "",
574 			(fsr & 0x04) ? "AFF " : "",
575 			(fsr & 0x08) ? "APF " : "",
576 			(fsr & 0x10) ? "TLBMF " : "",
577 			(fsr & 0x20) ? "HTWDEEF " : "",
578 			(fsr & 0x40) ? "HTWSEEF " : "",
579 			(fsr & 0x80) ? "MHF " : "",
580 			(fsr & 0x10000) ? "SL " : "",
581 			(fsr & 0x40000000) ? "SS " : "",
582 			(fsr & 0x80000000) ? "MULTI " : "");
583 
584 	pr_err("FSYNR0 = %08x    FSYNR1 = %08x\n",
585 	       GET_FSYNR0(base, ctx), GET_FSYNR1(base, ctx));
586 	pr_err("TTBR0  = %08x    TTBR1  = %08x\n",
587 	       GET_TTBR0(base, ctx), GET_TTBR1(base, ctx));
588 	pr_err("SCTLR  = %08x    ACTLR  = %08x\n",
589 	       GET_SCTLR(base, ctx), GET_ACTLR(base, ctx));
590 }
591 
592 static void insert_iommu_master(struct device *dev,
593 				struct msm_iommu_dev **iommu,
594 				struct of_phandle_args *spec)
595 {
596 	struct msm_iommu_ctx_dev *master = dev_iommu_priv_get(dev);
597 	int sid;
598 
599 	if (list_empty(&(*iommu)->ctx_list)) {
600 		master = kzalloc(sizeof(*master), GFP_ATOMIC);
601 		master->of_node = dev->of_node;
602 		list_add(&master->list, &(*iommu)->ctx_list);
603 		dev_iommu_priv_set(dev, master);
604 	}
605 
606 	for (sid = 0; sid < master->num_mids; sid++)
607 		if (master->mids[sid] == spec->args[0]) {
608 			dev_warn(dev, "Stream ID 0x%hx repeated; ignoring\n",
609 				 sid);
610 			return;
611 		}
612 
613 	master->mids[master->num_mids++] = spec->args[0];
614 }
615 
616 static int qcom_iommu_of_xlate(struct device *dev,
617 			       struct of_phandle_args *spec)
618 {
619 	struct msm_iommu_dev *iommu;
620 	unsigned long flags;
621 	int ret = 0;
622 
623 	spin_lock_irqsave(&msm_iommu_lock, flags);
624 	list_for_each_entry(iommu, &qcom_iommu_devices, dev_node)
625 		if (iommu->dev->of_node == spec->np)
626 			break;
627 
628 	if (!iommu || iommu->dev->of_node != spec->np) {
629 		ret = -ENODEV;
630 		goto fail;
631 	}
632 
633 	insert_iommu_master(dev, &iommu, spec);
634 fail:
635 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
636 
637 	return ret;
638 }
639 
640 irqreturn_t msm_iommu_fault_handler(int irq, void *dev_id)
641 {
642 	struct msm_iommu_dev *iommu = dev_id;
643 	unsigned int fsr;
644 	int i, ret;
645 
646 	spin_lock(&msm_iommu_lock);
647 
648 	if (!iommu) {
649 		pr_err("Invalid device ID in context interrupt handler\n");
650 		goto fail;
651 	}
652 
653 	pr_err("Unexpected IOMMU page fault!\n");
654 	pr_err("base = %08x\n", (unsigned int)iommu->base);
655 
656 	ret = __enable_clocks(iommu);
657 	if (ret)
658 		goto fail;
659 
660 	for (i = 0; i < iommu->ncb; i++) {
661 		fsr = GET_FSR(iommu->base, i);
662 		if (fsr) {
663 			pr_err("Fault occurred in context %d.\n", i);
664 			pr_err("Interesting registers:\n");
665 			print_ctx_regs(iommu->base, i);
666 			SET_FSR(iommu->base, i, 0x4000000F);
667 		}
668 	}
669 	__disable_clocks(iommu);
670 fail:
671 	spin_unlock(&msm_iommu_lock);
672 	return 0;
673 }
674 
675 static struct iommu_ops msm_iommu_ops = {
676 	.capable = msm_iommu_capable,
677 	.domain_alloc = msm_iommu_domain_alloc,
678 	.domain_free = msm_iommu_domain_free,
679 	.attach_dev = msm_iommu_attach_dev,
680 	.detach_dev = msm_iommu_detach_dev,
681 	.map = msm_iommu_map,
682 	.unmap = msm_iommu_unmap,
683 	/*
684 	 * Nothing is needed here, the barrier to guarantee
685 	 * completion of the tlb sync operation is implicitly
686 	 * taken care when the iommu client does a writel before
687 	 * kick starting the other master.
688 	 */
689 	.iotlb_sync = NULL,
690 	.iotlb_sync_map = msm_iommu_sync_map,
691 	.iova_to_phys = msm_iommu_iova_to_phys,
692 	.probe_device = msm_iommu_probe_device,
693 	.release_device = msm_iommu_release_device,
694 	.device_group = generic_device_group,
695 	.pgsize_bitmap = MSM_IOMMU_PGSIZES,
696 	.of_xlate = qcom_iommu_of_xlate,
697 };
698 
699 static int msm_iommu_probe(struct platform_device *pdev)
700 {
701 	struct resource *r;
702 	resource_size_t ioaddr;
703 	struct msm_iommu_dev *iommu;
704 	int ret, par, val;
705 
706 	iommu = devm_kzalloc(&pdev->dev, sizeof(*iommu), GFP_KERNEL);
707 	if (!iommu)
708 		return -ENODEV;
709 
710 	iommu->dev = &pdev->dev;
711 	INIT_LIST_HEAD(&iommu->ctx_list);
712 
713 	iommu->pclk = devm_clk_get(iommu->dev, "smmu_pclk");
714 	if (IS_ERR(iommu->pclk)) {
715 		dev_err(iommu->dev, "could not get smmu_pclk\n");
716 		return PTR_ERR(iommu->pclk);
717 	}
718 
719 	ret = clk_prepare(iommu->pclk);
720 	if (ret) {
721 		dev_err(iommu->dev, "could not prepare smmu_pclk\n");
722 		return ret;
723 	}
724 
725 	iommu->clk = devm_clk_get(iommu->dev, "iommu_clk");
726 	if (IS_ERR(iommu->clk)) {
727 		dev_err(iommu->dev, "could not get iommu_clk\n");
728 		clk_unprepare(iommu->pclk);
729 		return PTR_ERR(iommu->clk);
730 	}
731 
732 	ret = clk_prepare(iommu->clk);
733 	if (ret) {
734 		dev_err(iommu->dev, "could not prepare iommu_clk\n");
735 		clk_unprepare(iommu->pclk);
736 		return ret;
737 	}
738 
739 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
740 	iommu->base = devm_ioremap_resource(iommu->dev, r);
741 	if (IS_ERR(iommu->base)) {
742 		dev_err(iommu->dev, "could not get iommu base\n");
743 		ret = PTR_ERR(iommu->base);
744 		goto fail;
745 	}
746 	ioaddr = r->start;
747 
748 	iommu->irq = platform_get_irq(pdev, 0);
749 	if (iommu->irq < 0) {
750 		ret = -ENODEV;
751 		goto fail;
752 	}
753 
754 	ret = of_property_read_u32(iommu->dev->of_node, "qcom,ncb", &val);
755 	if (ret) {
756 		dev_err(iommu->dev, "could not get ncb\n");
757 		goto fail;
758 	}
759 	iommu->ncb = val;
760 
761 	msm_iommu_reset(iommu->base, iommu->ncb);
762 	SET_M(iommu->base, 0, 1);
763 	SET_PAR(iommu->base, 0, 0);
764 	SET_V2PCFG(iommu->base, 0, 1);
765 	SET_V2PPR(iommu->base, 0, 0);
766 	par = GET_PAR(iommu->base, 0);
767 	SET_V2PCFG(iommu->base, 0, 0);
768 	SET_M(iommu->base, 0, 0);
769 
770 	if (!par) {
771 		pr_err("Invalid PAR value detected\n");
772 		ret = -ENODEV;
773 		goto fail;
774 	}
775 
776 	ret = devm_request_threaded_irq(iommu->dev, iommu->irq, NULL,
777 					msm_iommu_fault_handler,
778 					IRQF_ONESHOT | IRQF_SHARED,
779 					"msm_iommu_secure_irpt_handler",
780 					iommu);
781 	if (ret) {
782 		pr_err("Request IRQ %d failed with ret=%d\n", iommu->irq, ret);
783 		goto fail;
784 	}
785 
786 	list_add(&iommu->dev_node, &qcom_iommu_devices);
787 
788 	ret = iommu_device_sysfs_add(&iommu->iommu, iommu->dev, NULL,
789 				     "msm-smmu.%pa", &ioaddr);
790 	if (ret) {
791 		pr_err("Could not add msm-smmu at %pa to sysfs\n", &ioaddr);
792 		goto fail;
793 	}
794 
795 	ret = iommu_device_register(&iommu->iommu, &msm_iommu_ops, &pdev->dev);
796 	if (ret) {
797 		pr_err("Could not register msm-smmu at %pa\n", &ioaddr);
798 		goto fail;
799 	}
800 
801 	bus_set_iommu(&platform_bus_type, &msm_iommu_ops);
802 
803 	pr_info("device mapped at %p, irq %d with %d ctx banks\n",
804 		iommu->base, iommu->irq, iommu->ncb);
805 
806 	return ret;
807 fail:
808 	clk_unprepare(iommu->clk);
809 	clk_unprepare(iommu->pclk);
810 	return ret;
811 }
812 
813 static const struct of_device_id msm_iommu_dt_match[] = {
814 	{ .compatible = "qcom,apq8064-iommu" },
815 	{}
816 };
817 
818 static int msm_iommu_remove(struct platform_device *pdev)
819 {
820 	struct msm_iommu_dev *iommu = platform_get_drvdata(pdev);
821 
822 	clk_unprepare(iommu->clk);
823 	clk_unprepare(iommu->pclk);
824 	return 0;
825 }
826 
827 static struct platform_driver msm_iommu_driver = {
828 	.driver = {
829 		.name	= "msm_iommu",
830 		.of_match_table = msm_iommu_dt_match,
831 	},
832 	.probe		= msm_iommu_probe,
833 	.remove		= msm_iommu_remove,
834 };
835 
836 static int __init msm_iommu_driver_init(void)
837 {
838 	int ret;
839 
840 	ret = platform_driver_register(&msm_iommu_driver);
841 	if (ret != 0)
842 		pr_err("Failed to register IOMMU driver\n");
843 
844 	return ret;
845 }
846 subsys_initcall(msm_iommu_driver_init);
847 
848