xref: /linux/drivers/iommu/msm_iommu.c (revision 9e56ff53b4115875667760445b028357848b4748)
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 
22 #include <asm/cacheflush.h>
23 #include <linux/sizes.h>
24 
25 #include "msm_iommu_hw-8xxx.h"
26 #include "msm_iommu.h"
27 
28 #define MRC(reg, processor, op1, crn, crm, op2)				\
29 __asm__ __volatile__ (							\
30 "   mrc   "   #processor "," #op1 ", %0,"  #crn "," #crm "," #op2 "\n"  \
31 : "=r" (reg))
32 
33 /* bitmap of the page sizes currently supported */
34 #define MSM_IOMMU_PGSIZES	(SZ_4K | SZ_64K | SZ_1M | SZ_16M)
35 
36 static DEFINE_SPINLOCK(msm_iommu_lock);
37 static LIST_HEAD(qcom_iommu_devices);
38 static struct iommu_ops msm_iommu_ops;
39 
40 struct msm_priv {
41 	struct list_head list_attached;
42 	struct iommu_domain domain;
43 	struct io_pgtable_cfg	cfg;
44 	struct io_pgtable_ops	*iop;
45 	struct device		*dev;
46 	spinlock_t		pgtlock; /* pagetable lock */
47 };
48 
49 static struct msm_priv *to_msm_priv(struct iommu_domain *dom)
50 {
51 	return container_of(dom, struct msm_priv, domain);
52 }
53 
54 static int __enable_clocks(struct msm_iommu_dev *iommu)
55 {
56 	int ret;
57 
58 	ret = clk_enable(iommu->pclk);
59 	if (ret)
60 		goto fail;
61 
62 	if (iommu->clk) {
63 		ret = clk_enable(iommu->clk);
64 		if (ret)
65 			clk_disable(iommu->pclk);
66 	}
67 fail:
68 	return ret;
69 }
70 
71 static void __disable_clocks(struct msm_iommu_dev *iommu)
72 {
73 	if (iommu->clk)
74 		clk_disable(iommu->clk);
75 	clk_disable(iommu->pclk);
76 }
77 
78 static void msm_iommu_reset(void __iomem *base, int ncb)
79 {
80 	int ctx;
81 
82 	SET_RPUE(base, 0);
83 	SET_RPUEIE(base, 0);
84 	SET_ESRRESTORE(base, 0);
85 	SET_TBE(base, 0);
86 	SET_CR(base, 0);
87 	SET_SPDMBE(base, 0);
88 	SET_TESTBUSCR(base, 0);
89 	SET_TLBRSW(base, 0);
90 	SET_GLOBAL_TLBIALL(base, 0);
91 	SET_RPU_ACR(base, 0);
92 	SET_TLBLKCRWE(base, 1);
93 
94 	for (ctx = 0; ctx < ncb; ctx++) {
95 		SET_BPRCOSH(base, ctx, 0);
96 		SET_BPRCISH(base, ctx, 0);
97 		SET_BPRCNSH(base, ctx, 0);
98 		SET_BPSHCFG(base, ctx, 0);
99 		SET_BPMTCFG(base, ctx, 0);
100 		SET_ACTLR(base, ctx, 0);
101 		SET_SCTLR(base, ctx, 0);
102 		SET_FSRRESTORE(base, ctx, 0);
103 		SET_TTBR0(base, ctx, 0);
104 		SET_TTBR1(base, ctx, 0);
105 		SET_TTBCR(base, ctx, 0);
106 		SET_BFBCR(base, ctx, 0);
107 		SET_PAR(base, ctx, 0);
108 		SET_FAR(base, ctx, 0);
109 		SET_CTX_TLBIALL(base, ctx, 0);
110 		SET_TLBFLPTER(base, ctx, 0);
111 		SET_TLBSLPTER(base, ctx, 0);
112 		SET_TLBLKCR(base, ctx, 0);
113 		SET_CONTEXTIDR(base, ctx, 0);
114 	}
115 }
116 
117 static void __flush_iotlb(void *cookie)
118 {
119 	struct msm_priv *priv = cookie;
120 	struct msm_iommu_dev *iommu = NULL;
121 	struct msm_iommu_ctx_dev *master;
122 	int ret = 0;
123 
124 	list_for_each_entry(iommu, &priv->list_attached, dom_node) {
125 		ret = __enable_clocks(iommu);
126 		if (ret)
127 			goto fail;
128 
129 		list_for_each_entry(master, &iommu->ctx_list, list)
130 			SET_CTX_TLBIALL(iommu->base, master->num, 0);
131 
132 		__disable_clocks(iommu);
133 	}
134 fail:
135 	return;
136 }
137 
138 static void __flush_iotlb_range(unsigned long iova, size_t size,
139 				size_t granule, bool leaf, void *cookie)
140 {
141 	struct msm_priv *priv = cookie;
142 	struct msm_iommu_dev *iommu = NULL;
143 	struct msm_iommu_ctx_dev *master;
144 	int ret = 0;
145 	int temp_size;
146 
147 	list_for_each_entry(iommu, &priv->list_attached, dom_node) {
148 		ret = __enable_clocks(iommu);
149 		if (ret)
150 			goto fail;
151 
152 		list_for_each_entry(master, &iommu->ctx_list, list) {
153 			temp_size = size;
154 			do {
155 				iova &= TLBIVA_VA;
156 				iova |= GET_CONTEXTIDR_ASID(iommu->base,
157 							    master->num);
158 				SET_TLBIVA(iommu->base, master->num, iova);
159 				iova += granule;
160 			} while (temp_size -= granule);
161 		}
162 
163 		__disable_clocks(iommu);
164 	}
165 
166 fail:
167 	return;
168 }
169 
170 static void __flush_iotlb_walk(unsigned long iova, size_t size,
171 			       size_t granule, void *cookie)
172 {
173 	__flush_iotlb_range(iova, size, granule, false, cookie);
174 }
175 
176 static void __flush_iotlb_page(struct iommu_iotlb_gather *gather,
177 			       unsigned long iova, size_t granule, void *cookie)
178 {
179 	__flush_iotlb_range(iova, granule, granule, true, cookie);
180 }
181 
182 static const struct iommu_flush_ops msm_iommu_flush_ops = {
183 	.tlb_flush_all = __flush_iotlb,
184 	.tlb_flush_walk = __flush_iotlb_walk,
185 	.tlb_add_page = __flush_iotlb_page,
186 };
187 
188 static int msm_iommu_alloc_ctx(unsigned long *map, int start, int end)
189 {
190 	int idx;
191 
192 	do {
193 		idx = find_next_zero_bit(map, end, start);
194 		if (idx == end)
195 			return -ENOSPC;
196 	} while (test_and_set_bit(idx, map));
197 
198 	return idx;
199 }
200 
201 static void msm_iommu_free_ctx(unsigned long *map, int idx)
202 {
203 	clear_bit(idx, map);
204 }
205 
206 static void config_mids(struct msm_iommu_dev *iommu,
207 			struct msm_iommu_ctx_dev *master)
208 {
209 	int mid, ctx, i;
210 
211 	for (i = 0; i < master->num_mids; i++) {
212 		mid = master->mids[i];
213 		ctx = master->num;
214 
215 		SET_M2VCBR_N(iommu->base, mid, 0);
216 		SET_CBACR_N(iommu->base, ctx, 0);
217 
218 		/* Set VMID = 0 */
219 		SET_VMID(iommu->base, mid, 0);
220 
221 		/* Set the context number for that MID to this context */
222 		SET_CBNDX(iommu->base, mid, ctx);
223 
224 		/* Set MID associated with this context bank to 0*/
225 		SET_CBVMID(iommu->base, ctx, 0);
226 
227 		/* Set the ASID for TLB tagging for this context */
228 		SET_CONTEXTIDR_ASID(iommu->base, ctx, ctx);
229 
230 		/* Set security bit override to be Non-secure */
231 		SET_NSCFG(iommu->base, mid, 3);
232 	}
233 }
234 
235 static void __reset_context(void __iomem *base, int ctx)
236 {
237 	SET_BPRCOSH(base, ctx, 0);
238 	SET_BPRCISH(base, ctx, 0);
239 	SET_BPRCNSH(base, ctx, 0);
240 	SET_BPSHCFG(base, ctx, 0);
241 	SET_BPMTCFG(base, ctx, 0);
242 	SET_ACTLR(base, ctx, 0);
243 	SET_SCTLR(base, ctx, 0);
244 	SET_FSRRESTORE(base, ctx, 0);
245 	SET_TTBR0(base, ctx, 0);
246 	SET_TTBR1(base, ctx, 0);
247 	SET_TTBCR(base, ctx, 0);
248 	SET_BFBCR(base, ctx, 0);
249 	SET_PAR(base, ctx, 0);
250 	SET_FAR(base, ctx, 0);
251 	SET_CTX_TLBIALL(base, ctx, 0);
252 	SET_TLBFLPTER(base, ctx, 0);
253 	SET_TLBSLPTER(base, ctx, 0);
254 	SET_TLBLKCR(base, ctx, 0);
255 }
256 
257 static void __program_context(void __iomem *base, int ctx,
258 			      struct msm_priv *priv)
259 {
260 	__reset_context(base, ctx);
261 
262 	/* Turn on TEX Remap */
263 	SET_TRE(base, ctx, 1);
264 	SET_AFE(base, ctx, 1);
265 
266 	/* Set up HTW mode */
267 	/* TLB miss configuration: perform HTW on miss */
268 	SET_TLBMCFG(base, ctx, 0x3);
269 
270 	/* V2P configuration: HTW for access */
271 	SET_V2PCFG(base, ctx, 0x3);
272 
273 	SET_TTBCR(base, ctx, priv->cfg.arm_v7s_cfg.tcr);
274 	SET_TTBR0(base, ctx, priv->cfg.arm_v7s_cfg.ttbr);
275 	SET_TTBR1(base, ctx, 0);
276 
277 	/* Set prrr and nmrr */
278 	SET_PRRR(base, ctx, priv->cfg.arm_v7s_cfg.prrr);
279 	SET_NMRR(base, ctx, priv->cfg.arm_v7s_cfg.nmrr);
280 
281 	/* Invalidate the TLB for this context */
282 	SET_CTX_TLBIALL(base, ctx, 0);
283 
284 	/* Set interrupt number to "secure" interrupt */
285 	SET_IRPTNDX(base, ctx, 0);
286 
287 	/* Enable context fault interrupt */
288 	SET_CFEIE(base, ctx, 1);
289 
290 	/* Stall access on a context fault and let the handler deal with it */
291 	SET_CFCFG(base, ctx, 1);
292 
293 	/* Redirect all cacheable requests to L2 slave port. */
294 	SET_RCISH(base, ctx, 1);
295 	SET_RCOSH(base, ctx, 1);
296 	SET_RCNSH(base, ctx, 1);
297 
298 	/* Turn on BFB prefetch */
299 	SET_BFBDFE(base, ctx, 1);
300 
301 	/* Enable the MMU */
302 	SET_M(base, ctx, 1);
303 }
304 
305 static struct iommu_domain *msm_iommu_domain_alloc_paging(struct device *dev)
306 {
307 	struct msm_priv *priv;
308 
309 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
310 	if (!priv)
311 		goto fail_nomem;
312 
313 	INIT_LIST_HEAD(&priv->list_attached);
314 
315 	priv->domain.geometry.aperture_start = 0;
316 	priv->domain.geometry.aperture_end   = (1ULL << 32) - 1;
317 	priv->domain.geometry.force_aperture = true;
318 
319 	return &priv->domain;
320 
321 fail_nomem:
322 	kfree(priv);
323 	return NULL;
324 }
325 
326 static void msm_iommu_domain_free(struct iommu_domain *domain)
327 {
328 	struct msm_priv *priv;
329 	unsigned long flags;
330 
331 	spin_lock_irqsave(&msm_iommu_lock, flags);
332 	priv = to_msm_priv(domain);
333 	kfree(priv);
334 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
335 }
336 
337 static int msm_iommu_domain_config(struct msm_priv *priv)
338 {
339 	spin_lock_init(&priv->pgtlock);
340 
341 	priv->cfg = (struct io_pgtable_cfg) {
342 		.pgsize_bitmap = msm_iommu_ops.pgsize_bitmap,
343 		.ias = 32,
344 		.oas = 32,
345 		.tlb = &msm_iommu_flush_ops,
346 		.iommu_dev = priv->dev,
347 	};
348 
349 	priv->iop = alloc_io_pgtable_ops(ARM_V7S, &priv->cfg, priv);
350 	if (!priv->iop) {
351 		dev_err(priv->dev, "Failed to allocate pgtable\n");
352 		return -EINVAL;
353 	}
354 
355 	msm_iommu_ops.pgsize_bitmap = priv->cfg.pgsize_bitmap;
356 
357 	return 0;
358 }
359 
360 /* Must be called under msm_iommu_lock */
361 static struct msm_iommu_dev *find_iommu_for_dev(struct device *dev)
362 {
363 	struct msm_iommu_dev *iommu, *ret = NULL;
364 	struct msm_iommu_ctx_dev *master;
365 
366 	list_for_each_entry(iommu, &qcom_iommu_devices, dev_node) {
367 		master = list_first_entry(&iommu->ctx_list,
368 					  struct msm_iommu_ctx_dev,
369 					  list);
370 		if (master->of_node == dev->of_node) {
371 			ret = iommu;
372 			break;
373 		}
374 	}
375 
376 	return ret;
377 }
378 
379 static struct iommu_device *msm_iommu_probe_device(struct device *dev)
380 {
381 	struct msm_iommu_dev *iommu;
382 	unsigned long flags;
383 
384 	spin_lock_irqsave(&msm_iommu_lock, flags);
385 	iommu = find_iommu_for_dev(dev);
386 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
387 
388 	if (!iommu)
389 		return ERR_PTR(-ENODEV);
390 
391 	return &iommu->iommu;
392 }
393 
394 static int msm_iommu_attach_dev(struct iommu_domain *domain, struct device *dev)
395 {
396 	int ret = 0;
397 	unsigned long flags;
398 	struct msm_iommu_dev *iommu;
399 	struct msm_priv *priv = to_msm_priv(domain);
400 	struct msm_iommu_ctx_dev *master;
401 
402 	priv->dev = dev;
403 	msm_iommu_domain_config(priv);
404 
405 	spin_lock_irqsave(&msm_iommu_lock, flags);
406 	list_for_each_entry(iommu, &qcom_iommu_devices, dev_node) {
407 		master = list_first_entry(&iommu->ctx_list,
408 					  struct msm_iommu_ctx_dev,
409 					  list);
410 		if (master->of_node == dev->of_node) {
411 			ret = __enable_clocks(iommu);
412 			if (ret)
413 				goto fail;
414 
415 			list_for_each_entry(master, &iommu->ctx_list, list) {
416 				if (master->num) {
417 					dev_err(dev, "domain already attached");
418 					ret = -EEXIST;
419 					goto fail;
420 				}
421 				master->num =
422 					msm_iommu_alloc_ctx(iommu->context_map,
423 							    0, iommu->ncb);
424 				if (IS_ERR_VALUE(master->num)) {
425 					ret = -ENODEV;
426 					goto fail;
427 				}
428 				config_mids(iommu, master);
429 				__program_context(iommu->base, master->num,
430 						  priv);
431 			}
432 			__disable_clocks(iommu);
433 			list_add(&iommu->dom_node, &priv->list_attached);
434 		}
435 	}
436 
437 fail:
438 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
439 
440 	return ret;
441 }
442 
443 static int msm_iommu_identity_attach(struct iommu_domain *identity_domain,
444 				     struct device *dev)
445 {
446 	struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
447 	struct msm_priv *priv;
448 	unsigned long flags;
449 	struct msm_iommu_dev *iommu;
450 	struct msm_iommu_ctx_dev *master;
451 	int ret = 0;
452 
453 	if (domain == identity_domain || !domain)
454 		return 0;
455 
456 	priv = to_msm_priv(domain);
457 	free_io_pgtable_ops(priv->iop);
458 
459 	spin_lock_irqsave(&msm_iommu_lock, flags);
460 	list_for_each_entry(iommu, &priv->list_attached, dom_node) {
461 		ret = __enable_clocks(iommu);
462 		if (ret)
463 			goto fail;
464 
465 		list_for_each_entry(master, &iommu->ctx_list, list) {
466 			msm_iommu_free_ctx(iommu->context_map, master->num);
467 			__reset_context(iommu->base, master->num);
468 		}
469 		__disable_clocks(iommu);
470 	}
471 fail:
472 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
473 	return ret;
474 }
475 
476 static struct iommu_domain_ops msm_iommu_identity_ops = {
477 	.attach_dev = msm_iommu_identity_attach,
478 };
479 
480 static struct iommu_domain msm_iommu_identity_domain = {
481 	.type = IOMMU_DOMAIN_IDENTITY,
482 	.ops = &msm_iommu_identity_ops,
483 };
484 
485 static int msm_iommu_map(struct iommu_domain *domain, unsigned long iova,
486 			 phys_addr_t pa, size_t pgsize, size_t pgcount,
487 			 int prot, gfp_t gfp, size_t *mapped)
488 {
489 	struct msm_priv *priv = to_msm_priv(domain);
490 	unsigned long flags;
491 	int ret;
492 
493 	spin_lock_irqsave(&priv->pgtlock, flags);
494 	ret = priv->iop->map_pages(priv->iop, iova, pa, pgsize, pgcount, prot,
495 				   GFP_ATOMIC, mapped);
496 	spin_unlock_irqrestore(&priv->pgtlock, flags);
497 
498 	return ret;
499 }
500 
501 static int msm_iommu_sync_map(struct iommu_domain *domain, unsigned long iova,
502 			      size_t size)
503 {
504 	struct msm_priv *priv = to_msm_priv(domain);
505 
506 	__flush_iotlb_range(iova, size, SZ_4K, false, priv);
507 	return 0;
508 }
509 
510 static size_t msm_iommu_unmap(struct iommu_domain *domain, unsigned long iova,
511 			      size_t pgsize, size_t pgcount,
512 			      struct iommu_iotlb_gather *gather)
513 {
514 	struct msm_priv *priv = to_msm_priv(domain);
515 	unsigned long flags;
516 	size_t ret;
517 
518 	spin_lock_irqsave(&priv->pgtlock, flags);
519 	ret = priv->iop->unmap_pages(priv->iop, iova, pgsize, pgcount, gather);
520 	spin_unlock_irqrestore(&priv->pgtlock, flags);
521 
522 	return ret;
523 }
524 
525 static phys_addr_t msm_iommu_iova_to_phys(struct iommu_domain *domain,
526 					  dma_addr_t va)
527 {
528 	struct msm_priv *priv;
529 	struct msm_iommu_dev *iommu;
530 	struct msm_iommu_ctx_dev *master;
531 	unsigned int par;
532 	unsigned long flags;
533 	phys_addr_t ret = 0;
534 
535 	spin_lock_irqsave(&msm_iommu_lock, flags);
536 
537 	priv = to_msm_priv(domain);
538 	iommu = list_first_entry(&priv->list_attached,
539 				 struct msm_iommu_dev, dom_node);
540 
541 	if (list_empty(&iommu->ctx_list))
542 		goto fail;
543 
544 	master = list_first_entry(&iommu->ctx_list,
545 				  struct msm_iommu_ctx_dev, list);
546 	if (!master)
547 		goto fail;
548 
549 	ret = __enable_clocks(iommu);
550 	if (ret)
551 		goto fail;
552 
553 	/* Invalidate context TLB */
554 	SET_CTX_TLBIALL(iommu->base, master->num, 0);
555 	SET_V2PPR(iommu->base, master->num, va & V2Pxx_VA);
556 
557 	par = GET_PAR(iommu->base, master->num);
558 
559 	/* We are dealing with a supersection */
560 	if (GET_NOFAULT_SS(iommu->base, master->num))
561 		ret = (par & 0xFF000000) | (va & 0x00FFFFFF);
562 	else	/* Upper 20 bits from PAR, lower 12 from VA */
563 		ret = (par & 0xFFFFF000) | (va & 0x00000FFF);
564 
565 	if (GET_FAULT(iommu->base, master->num))
566 		ret = 0;
567 
568 	__disable_clocks(iommu);
569 fail:
570 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
571 	return ret;
572 }
573 
574 static void print_ctx_regs(void __iomem *base, int ctx)
575 {
576 	unsigned int fsr = GET_FSR(base, ctx);
577 	pr_err("FAR    = %08x    PAR    = %08x\n",
578 	       GET_FAR(base, ctx), GET_PAR(base, ctx));
579 	pr_err("FSR    = %08x [%s%s%s%s%s%s%s%s%s%s]\n", fsr,
580 			(fsr & 0x02) ? "TF " : "",
581 			(fsr & 0x04) ? "AFF " : "",
582 			(fsr & 0x08) ? "APF " : "",
583 			(fsr & 0x10) ? "TLBMF " : "",
584 			(fsr & 0x20) ? "HTWDEEF " : "",
585 			(fsr & 0x40) ? "HTWSEEF " : "",
586 			(fsr & 0x80) ? "MHF " : "",
587 			(fsr & 0x10000) ? "SL " : "",
588 			(fsr & 0x40000000) ? "SS " : "",
589 			(fsr & 0x80000000) ? "MULTI " : "");
590 
591 	pr_err("FSYNR0 = %08x    FSYNR1 = %08x\n",
592 	       GET_FSYNR0(base, ctx), GET_FSYNR1(base, ctx));
593 	pr_err("TTBR0  = %08x    TTBR1  = %08x\n",
594 	       GET_TTBR0(base, ctx), GET_TTBR1(base, ctx));
595 	pr_err("SCTLR  = %08x    ACTLR  = %08x\n",
596 	       GET_SCTLR(base, ctx), GET_ACTLR(base, ctx));
597 }
598 
599 static int insert_iommu_master(struct device *dev,
600 				struct msm_iommu_dev **iommu,
601 				struct of_phandle_args *spec)
602 {
603 	struct msm_iommu_ctx_dev *master = dev_iommu_priv_get(dev);
604 	int sid;
605 
606 	if (list_empty(&(*iommu)->ctx_list)) {
607 		master = kzalloc(sizeof(*master), GFP_ATOMIC);
608 		if (!master) {
609 			dev_err(dev, "Failed to allocate iommu_master\n");
610 			return -ENOMEM;
611 		}
612 		master->of_node = dev->of_node;
613 		list_add(&master->list, &(*iommu)->ctx_list);
614 		dev_iommu_priv_set(dev, master);
615 	}
616 
617 	for (sid = 0; sid < master->num_mids; sid++)
618 		if (master->mids[sid] == spec->args[0]) {
619 			dev_warn(dev, "Stream ID 0x%x repeated; ignoring\n",
620 				 sid);
621 			return 0;
622 		}
623 
624 	master->mids[master->num_mids++] = spec->args[0];
625 	return 0;
626 }
627 
628 static int qcom_iommu_of_xlate(struct device *dev,
629 			       struct of_phandle_args *spec)
630 {
631 	struct msm_iommu_dev *iommu = NULL, *iter;
632 	unsigned long flags;
633 	int ret = 0;
634 
635 	spin_lock_irqsave(&msm_iommu_lock, flags);
636 	list_for_each_entry(iter, &qcom_iommu_devices, dev_node) {
637 		if (iter->dev->of_node == spec->np) {
638 			iommu = iter;
639 			break;
640 		}
641 	}
642 
643 	if (!iommu) {
644 		ret = -ENODEV;
645 		goto fail;
646 	}
647 
648 	ret = insert_iommu_master(dev, &iommu, spec);
649 fail:
650 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
651 
652 	return ret;
653 }
654 
655 irqreturn_t msm_iommu_fault_handler(int irq, void *dev_id)
656 {
657 	struct msm_iommu_dev *iommu = dev_id;
658 	unsigned int fsr;
659 	int i, ret;
660 
661 	spin_lock(&msm_iommu_lock);
662 
663 	if (!iommu) {
664 		pr_err("Invalid device ID in context interrupt handler\n");
665 		goto fail;
666 	}
667 
668 	pr_err("Unexpected IOMMU page fault!\n");
669 	pr_err("base = %08x\n", (unsigned int)iommu->base);
670 
671 	ret = __enable_clocks(iommu);
672 	if (ret)
673 		goto fail;
674 
675 	for (i = 0; i < iommu->ncb; i++) {
676 		fsr = GET_FSR(iommu->base, i);
677 		if (fsr) {
678 			pr_err("Fault occurred in context %d.\n", i);
679 			pr_err("Interesting registers:\n");
680 			print_ctx_regs(iommu->base, i);
681 			SET_FSR(iommu->base, i, 0x4000000F);
682 		}
683 	}
684 	__disable_clocks(iommu);
685 fail:
686 	spin_unlock(&msm_iommu_lock);
687 	return 0;
688 }
689 
690 static struct iommu_ops msm_iommu_ops = {
691 	.identity_domain = &msm_iommu_identity_domain,
692 	.domain_alloc_paging = msm_iommu_domain_alloc_paging,
693 	.probe_device = msm_iommu_probe_device,
694 	.device_group = generic_device_group,
695 	.pgsize_bitmap = MSM_IOMMU_PGSIZES,
696 	.of_xlate = qcom_iommu_of_xlate,
697 	.default_domain_ops = &(const struct iommu_domain_ops) {
698 		.attach_dev	= msm_iommu_attach_dev,
699 		.map_pages	= msm_iommu_map,
700 		.unmap_pages	= msm_iommu_unmap,
701 		/*
702 		 * Nothing is needed here, the barrier to guarantee
703 		 * completion of the tlb sync operation is implicitly
704 		 * taken care when the iommu client does a writel before
705 		 * kick starting the other master.
706 		 */
707 		.iotlb_sync	= NULL,
708 		.iotlb_sync_map	= msm_iommu_sync_map,
709 		.iova_to_phys	= msm_iommu_iova_to_phys,
710 		.free		= msm_iommu_domain_free,
711 	}
712 };
713 
714 static int msm_iommu_probe(struct platform_device *pdev)
715 {
716 	struct resource *r;
717 	resource_size_t ioaddr;
718 	struct msm_iommu_dev *iommu;
719 	int ret, par, val;
720 
721 	iommu = devm_kzalloc(&pdev->dev, sizeof(*iommu), GFP_KERNEL);
722 	if (!iommu)
723 		return -ENODEV;
724 
725 	iommu->dev = &pdev->dev;
726 	INIT_LIST_HEAD(&iommu->ctx_list);
727 
728 	iommu->pclk = devm_clk_get(iommu->dev, "smmu_pclk");
729 	if (IS_ERR(iommu->pclk))
730 		return dev_err_probe(iommu->dev, PTR_ERR(iommu->pclk),
731 				     "could not get smmu_pclk\n");
732 
733 	ret = clk_prepare(iommu->pclk);
734 	if (ret)
735 		return dev_err_probe(iommu->dev, ret,
736 				     "could not prepare smmu_pclk\n");
737 
738 	iommu->clk = devm_clk_get(iommu->dev, "iommu_clk");
739 	if (IS_ERR(iommu->clk)) {
740 		clk_unprepare(iommu->pclk);
741 		return dev_err_probe(iommu->dev, PTR_ERR(iommu->clk),
742 				     "could not get iommu_clk\n");
743 	}
744 
745 	ret = clk_prepare(iommu->clk);
746 	if (ret) {
747 		clk_unprepare(iommu->pclk);
748 		return dev_err_probe(iommu->dev, ret, "could not prepare iommu_clk\n");
749 	}
750 
751 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
752 	iommu->base = devm_ioremap_resource(iommu->dev, r);
753 	if (IS_ERR(iommu->base)) {
754 		ret = dev_err_probe(iommu->dev, PTR_ERR(iommu->base), "could not get iommu base\n");
755 		goto fail;
756 	}
757 	ioaddr = r->start;
758 
759 	iommu->irq = platform_get_irq(pdev, 0);
760 	if (iommu->irq < 0) {
761 		ret = -ENODEV;
762 		goto fail;
763 	}
764 
765 	ret = of_property_read_u32(iommu->dev->of_node, "qcom,ncb", &val);
766 	if (ret) {
767 		dev_err(iommu->dev, "could not get ncb\n");
768 		goto fail;
769 	}
770 	iommu->ncb = val;
771 
772 	msm_iommu_reset(iommu->base, iommu->ncb);
773 	SET_M(iommu->base, 0, 1);
774 	SET_PAR(iommu->base, 0, 0);
775 	SET_V2PCFG(iommu->base, 0, 1);
776 	SET_V2PPR(iommu->base, 0, 0);
777 	par = GET_PAR(iommu->base, 0);
778 	SET_V2PCFG(iommu->base, 0, 0);
779 	SET_M(iommu->base, 0, 0);
780 
781 	if (!par) {
782 		pr_err("Invalid PAR value detected\n");
783 		ret = -ENODEV;
784 		goto fail;
785 	}
786 
787 	ret = devm_request_threaded_irq(iommu->dev, iommu->irq, NULL,
788 					msm_iommu_fault_handler,
789 					IRQF_ONESHOT | IRQF_SHARED,
790 					"msm_iommu_secure_irpt_handler",
791 					iommu);
792 	if (ret) {
793 		pr_err("Request IRQ %d failed with ret=%d\n", iommu->irq, ret);
794 		goto fail;
795 	}
796 
797 	list_add(&iommu->dev_node, &qcom_iommu_devices);
798 
799 	ret = iommu_device_sysfs_add(&iommu->iommu, iommu->dev, NULL,
800 				     "msm-smmu.%pa", &ioaddr);
801 	if (ret) {
802 		pr_err("Could not add msm-smmu at %pa to sysfs\n", &ioaddr);
803 		goto fail;
804 	}
805 
806 	ret = iommu_device_register(&iommu->iommu, &msm_iommu_ops, &pdev->dev);
807 	if (ret) {
808 		pr_err("Could not register msm-smmu at %pa\n", &ioaddr);
809 		goto fail;
810 	}
811 
812 	pr_info("device mapped at %p, irq %d with %d ctx banks\n",
813 		iommu->base, iommu->irq, iommu->ncb);
814 
815 	return ret;
816 fail:
817 	clk_unprepare(iommu->clk);
818 	clk_unprepare(iommu->pclk);
819 	return ret;
820 }
821 
822 static const struct of_device_id msm_iommu_dt_match[] = {
823 	{ .compatible = "qcom,apq8064-iommu" },
824 	{}
825 };
826 
827 static void msm_iommu_remove(struct platform_device *pdev)
828 {
829 	struct msm_iommu_dev *iommu = platform_get_drvdata(pdev);
830 
831 	clk_unprepare(iommu->clk);
832 	clk_unprepare(iommu->pclk);
833 }
834 
835 static struct platform_driver msm_iommu_driver = {
836 	.driver = {
837 		.name	= "msm_iommu",
838 		.of_match_table = msm_iommu_dt_match,
839 	},
840 	.probe		= msm_iommu_probe,
841 	.remove_new	= msm_iommu_remove,
842 };
843 builtin_platform_driver(msm_iommu_driver);
844