xref: /openbmc/linux/drivers/iommu/msm_iommu.c (revision e15a5365)
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_leaf(unsigned long iova, size_t size,
178 			       size_t granule, void *cookie)
179 {
180 	__flush_iotlb_range(iova, size, granule, true, cookie);
181 }
182 
183 static void __flush_iotlb_page(struct iommu_iotlb_gather *gather,
184 			       unsigned long iova, size_t granule, void *cookie)
185 {
186 	__flush_iotlb_range(iova, granule, granule, true, cookie);
187 }
188 
189 static const struct iommu_flush_ops msm_iommu_flush_ops = {
190 	.tlb_flush_all = __flush_iotlb,
191 	.tlb_flush_walk = __flush_iotlb_walk,
192 	.tlb_flush_leaf = __flush_iotlb_leaf,
193 	.tlb_add_page = __flush_iotlb_page,
194 };
195 
196 static int msm_iommu_alloc_ctx(unsigned long *map, int start, int end)
197 {
198 	int idx;
199 
200 	do {
201 		idx = find_next_zero_bit(map, end, start);
202 		if (idx == end)
203 			return -ENOSPC;
204 	} while (test_and_set_bit(idx, map));
205 
206 	return idx;
207 }
208 
209 static void msm_iommu_free_ctx(unsigned long *map, int idx)
210 {
211 	clear_bit(idx, map);
212 }
213 
214 static void config_mids(struct msm_iommu_dev *iommu,
215 			struct msm_iommu_ctx_dev *master)
216 {
217 	int mid, ctx, i;
218 
219 	for (i = 0; i < master->num_mids; i++) {
220 		mid = master->mids[i];
221 		ctx = master->num;
222 
223 		SET_M2VCBR_N(iommu->base, mid, 0);
224 		SET_CBACR_N(iommu->base, ctx, 0);
225 
226 		/* Set VMID = 0 */
227 		SET_VMID(iommu->base, mid, 0);
228 
229 		/* Set the context number for that MID to this context */
230 		SET_CBNDX(iommu->base, mid, ctx);
231 
232 		/* Set MID associated with this context bank to 0*/
233 		SET_CBVMID(iommu->base, ctx, 0);
234 
235 		/* Set the ASID for TLB tagging for this context */
236 		SET_CONTEXTIDR_ASID(iommu->base, ctx, ctx);
237 
238 		/* Set security bit override to be Non-secure */
239 		SET_NSCFG(iommu->base, mid, 3);
240 	}
241 }
242 
243 static void __reset_context(void __iomem *base, int ctx)
244 {
245 	SET_BPRCOSH(base, ctx, 0);
246 	SET_BPRCISH(base, ctx, 0);
247 	SET_BPRCNSH(base, ctx, 0);
248 	SET_BPSHCFG(base, ctx, 0);
249 	SET_BPMTCFG(base, ctx, 0);
250 	SET_ACTLR(base, ctx, 0);
251 	SET_SCTLR(base, ctx, 0);
252 	SET_FSRRESTORE(base, ctx, 0);
253 	SET_TTBR0(base, ctx, 0);
254 	SET_TTBR1(base, ctx, 0);
255 	SET_TTBCR(base, ctx, 0);
256 	SET_BFBCR(base, ctx, 0);
257 	SET_PAR(base, ctx, 0);
258 	SET_FAR(base, ctx, 0);
259 	SET_CTX_TLBIALL(base, ctx, 0);
260 	SET_TLBFLPTER(base, ctx, 0);
261 	SET_TLBSLPTER(base, ctx, 0);
262 	SET_TLBLKCR(base, ctx, 0);
263 }
264 
265 static void __program_context(void __iomem *base, int ctx,
266 			      struct msm_priv *priv)
267 {
268 	__reset_context(base, ctx);
269 
270 	/* Turn on TEX Remap */
271 	SET_TRE(base, ctx, 1);
272 	SET_AFE(base, ctx, 1);
273 
274 	/* Set up HTW mode */
275 	/* TLB miss configuration: perform HTW on miss */
276 	SET_TLBMCFG(base, ctx, 0x3);
277 
278 	/* V2P configuration: HTW for access */
279 	SET_V2PCFG(base, ctx, 0x3);
280 
281 	SET_TTBCR(base, ctx, priv->cfg.arm_v7s_cfg.tcr);
282 	SET_TTBR0(base, ctx, priv->cfg.arm_v7s_cfg.ttbr);
283 	SET_TTBR1(base, ctx, 0);
284 
285 	/* Set prrr and nmrr */
286 	SET_PRRR(base, ctx, priv->cfg.arm_v7s_cfg.prrr);
287 	SET_NMRR(base, ctx, priv->cfg.arm_v7s_cfg.nmrr);
288 
289 	/* Invalidate the TLB for this context */
290 	SET_CTX_TLBIALL(base, ctx, 0);
291 
292 	/* Set interrupt number to "secure" interrupt */
293 	SET_IRPTNDX(base, ctx, 0);
294 
295 	/* Enable context fault interrupt */
296 	SET_CFEIE(base, ctx, 1);
297 
298 	/* Stall access on a context fault and let the handler deal with it */
299 	SET_CFCFG(base, ctx, 1);
300 
301 	/* Redirect all cacheable requests to L2 slave port. */
302 	SET_RCISH(base, ctx, 1);
303 	SET_RCOSH(base, ctx, 1);
304 	SET_RCNSH(base, ctx, 1);
305 
306 	/* Turn on BFB prefetch */
307 	SET_BFBDFE(base, ctx, 1);
308 
309 	/* Enable the MMU */
310 	SET_M(base, ctx, 1);
311 }
312 
313 static struct iommu_domain *msm_iommu_domain_alloc(unsigned type)
314 {
315 	struct msm_priv *priv;
316 
317 	if (type != IOMMU_DOMAIN_UNMANAGED)
318 		return NULL;
319 
320 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
321 	if (!priv)
322 		goto fail_nomem;
323 
324 	INIT_LIST_HEAD(&priv->list_attached);
325 
326 	priv->domain.geometry.aperture_start = 0;
327 	priv->domain.geometry.aperture_end   = (1ULL << 32) - 1;
328 	priv->domain.geometry.force_aperture = true;
329 
330 	return &priv->domain;
331 
332 fail_nomem:
333 	kfree(priv);
334 	return NULL;
335 }
336 
337 static void msm_iommu_domain_free(struct iommu_domain *domain)
338 {
339 	struct msm_priv *priv;
340 	unsigned long flags;
341 
342 	spin_lock_irqsave(&msm_iommu_lock, flags);
343 	priv = to_msm_priv(domain);
344 	kfree(priv);
345 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
346 }
347 
348 static int msm_iommu_domain_config(struct msm_priv *priv)
349 {
350 	spin_lock_init(&priv->pgtlock);
351 
352 	priv->cfg = (struct io_pgtable_cfg) {
353 		.quirks = IO_PGTABLE_QUIRK_TLBI_ON_MAP,
354 		.pgsize_bitmap = msm_iommu_ops.pgsize_bitmap,
355 		.ias = 32,
356 		.oas = 32,
357 		.tlb = &msm_iommu_flush_ops,
358 		.iommu_dev = priv->dev,
359 	};
360 
361 	priv->iop = alloc_io_pgtable_ops(ARM_V7S, &priv->cfg, priv);
362 	if (!priv->iop) {
363 		dev_err(priv->dev, "Failed to allocate pgtable\n");
364 		return -EINVAL;
365 	}
366 
367 	msm_iommu_ops.pgsize_bitmap = priv->cfg.pgsize_bitmap;
368 
369 	return 0;
370 }
371 
372 /* Must be called under msm_iommu_lock */
373 static struct msm_iommu_dev *find_iommu_for_dev(struct device *dev)
374 {
375 	struct msm_iommu_dev *iommu, *ret = NULL;
376 	struct msm_iommu_ctx_dev *master;
377 
378 	list_for_each_entry(iommu, &qcom_iommu_devices, dev_node) {
379 		master = list_first_entry(&iommu->ctx_list,
380 					  struct msm_iommu_ctx_dev,
381 					  list);
382 		if (master->of_node == dev->of_node) {
383 			ret = iommu;
384 			break;
385 		}
386 	}
387 
388 	return ret;
389 }
390 
391 static struct iommu_device *msm_iommu_probe_device(struct device *dev)
392 {
393 	struct msm_iommu_dev *iommu;
394 	unsigned long flags;
395 
396 	spin_lock_irqsave(&msm_iommu_lock, flags);
397 	iommu = find_iommu_for_dev(dev);
398 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
399 
400 	if (!iommu)
401 		return ERR_PTR(-ENODEV);
402 
403 	return &iommu->iommu;
404 }
405 
406 static void msm_iommu_release_device(struct device *dev)
407 {
408 }
409 
410 static int msm_iommu_attach_dev(struct iommu_domain *domain, struct device *dev)
411 {
412 	int ret = 0;
413 	unsigned long flags;
414 	struct msm_iommu_dev *iommu;
415 	struct msm_priv *priv = to_msm_priv(domain);
416 	struct msm_iommu_ctx_dev *master;
417 
418 	priv->dev = dev;
419 	msm_iommu_domain_config(priv);
420 
421 	spin_lock_irqsave(&msm_iommu_lock, flags);
422 	list_for_each_entry(iommu, &qcom_iommu_devices, dev_node) {
423 		master = list_first_entry(&iommu->ctx_list,
424 					  struct msm_iommu_ctx_dev,
425 					  list);
426 		if (master->of_node == dev->of_node) {
427 			ret = __enable_clocks(iommu);
428 			if (ret)
429 				goto fail;
430 
431 			list_for_each_entry(master, &iommu->ctx_list, list) {
432 				if (master->num) {
433 					dev_err(dev, "domain already attached");
434 					ret = -EEXIST;
435 					goto fail;
436 				}
437 				master->num =
438 					msm_iommu_alloc_ctx(iommu->context_map,
439 							    0, iommu->ncb);
440 				if (IS_ERR_VALUE(master->num)) {
441 					ret = -ENODEV;
442 					goto fail;
443 				}
444 				config_mids(iommu, master);
445 				__program_context(iommu->base, master->num,
446 						  priv);
447 			}
448 			__disable_clocks(iommu);
449 			list_add(&iommu->dom_node, &priv->list_attached);
450 		}
451 	}
452 
453 fail:
454 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
455 
456 	return ret;
457 }
458 
459 static void msm_iommu_detach_dev(struct iommu_domain *domain,
460 				 struct device *dev)
461 {
462 	struct msm_priv *priv = to_msm_priv(domain);
463 	unsigned long flags;
464 	struct msm_iommu_dev *iommu;
465 	struct msm_iommu_ctx_dev *master;
466 	int ret;
467 
468 	free_io_pgtable_ops(priv->iop);
469 
470 	spin_lock_irqsave(&msm_iommu_lock, flags);
471 	list_for_each_entry(iommu, &priv->list_attached, dom_node) {
472 		ret = __enable_clocks(iommu);
473 		if (ret)
474 			goto fail;
475 
476 		list_for_each_entry(master, &iommu->ctx_list, list) {
477 			msm_iommu_free_ctx(iommu->context_map, master->num);
478 			__reset_context(iommu->base, master->num);
479 		}
480 		__disable_clocks(iommu);
481 	}
482 fail:
483 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
484 }
485 
486 static int msm_iommu_map(struct iommu_domain *domain, unsigned long iova,
487 			 phys_addr_t pa, size_t len, int prot, gfp_t gfp)
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(priv->iop, iova, pa, len, prot, GFP_ATOMIC);
495 	spin_unlock_irqrestore(&priv->pgtlock, flags);
496 
497 	return ret;
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 	.iova_to_phys = msm_iommu_iova_to_phys,
691 	.probe_device = msm_iommu_probe_device,
692 	.release_device = msm_iommu_release_device,
693 	.device_group = generic_device_group,
694 	.pgsize_bitmap = MSM_IOMMU_PGSIZES,
695 	.of_xlate = qcom_iommu_of_xlate,
696 };
697 
698 static int msm_iommu_probe(struct platform_device *pdev)
699 {
700 	struct resource *r;
701 	resource_size_t ioaddr;
702 	struct msm_iommu_dev *iommu;
703 	int ret, par, val;
704 
705 	iommu = devm_kzalloc(&pdev->dev, sizeof(*iommu), GFP_KERNEL);
706 	if (!iommu)
707 		return -ENODEV;
708 
709 	iommu->dev = &pdev->dev;
710 	INIT_LIST_HEAD(&iommu->ctx_list);
711 
712 	iommu->pclk = devm_clk_get(iommu->dev, "smmu_pclk");
713 	if (IS_ERR(iommu->pclk)) {
714 		dev_err(iommu->dev, "could not get smmu_pclk\n");
715 		return PTR_ERR(iommu->pclk);
716 	}
717 
718 	ret = clk_prepare(iommu->pclk);
719 	if (ret) {
720 		dev_err(iommu->dev, "could not prepare smmu_pclk\n");
721 		return ret;
722 	}
723 
724 	iommu->clk = devm_clk_get(iommu->dev, "iommu_clk");
725 	if (IS_ERR(iommu->clk)) {
726 		dev_err(iommu->dev, "could not get iommu_clk\n");
727 		clk_unprepare(iommu->pclk);
728 		return PTR_ERR(iommu->clk);
729 	}
730 
731 	ret = clk_prepare(iommu->clk);
732 	if (ret) {
733 		dev_err(iommu->dev, "could not prepare iommu_clk\n");
734 		clk_unprepare(iommu->pclk);
735 		return ret;
736 	}
737 
738 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
739 	iommu->base = devm_ioremap_resource(iommu->dev, r);
740 	if (IS_ERR(iommu->base)) {
741 		dev_err(iommu->dev, "could not get iommu base\n");
742 		ret = PTR_ERR(iommu->base);
743 		goto fail;
744 	}
745 	ioaddr = r->start;
746 
747 	iommu->irq = platform_get_irq(pdev, 0);
748 	if (iommu->irq < 0) {
749 		ret = -ENODEV;
750 		goto fail;
751 	}
752 
753 	ret = of_property_read_u32(iommu->dev->of_node, "qcom,ncb", &val);
754 	if (ret) {
755 		dev_err(iommu->dev, "could not get ncb\n");
756 		goto fail;
757 	}
758 	iommu->ncb = val;
759 
760 	msm_iommu_reset(iommu->base, iommu->ncb);
761 	SET_M(iommu->base, 0, 1);
762 	SET_PAR(iommu->base, 0, 0);
763 	SET_V2PCFG(iommu->base, 0, 1);
764 	SET_V2PPR(iommu->base, 0, 0);
765 	par = GET_PAR(iommu->base, 0);
766 	SET_V2PCFG(iommu->base, 0, 0);
767 	SET_M(iommu->base, 0, 0);
768 
769 	if (!par) {
770 		pr_err("Invalid PAR value detected\n");
771 		ret = -ENODEV;
772 		goto fail;
773 	}
774 
775 	ret = devm_request_threaded_irq(iommu->dev, iommu->irq, NULL,
776 					msm_iommu_fault_handler,
777 					IRQF_ONESHOT | IRQF_SHARED,
778 					"msm_iommu_secure_irpt_handler",
779 					iommu);
780 	if (ret) {
781 		pr_err("Request IRQ %d failed with ret=%d\n", iommu->irq, ret);
782 		goto fail;
783 	}
784 
785 	list_add(&iommu->dev_node, &qcom_iommu_devices);
786 
787 	ret = iommu_device_sysfs_add(&iommu->iommu, iommu->dev, NULL,
788 				     "msm-smmu.%pa", &ioaddr);
789 	if (ret) {
790 		pr_err("Could not add msm-smmu at %pa to sysfs\n", &ioaddr);
791 		goto fail;
792 	}
793 
794 	iommu_device_set_ops(&iommu->iommu, &msm_iommu_ops);
795 	iommu_device_set_fwnode(&iommu->iommu, &pdev->dev.of_node->fwnode);
796 
797 	ret = iommu_device_register(&iommu->iommu);
798 	if (ret) {
799 		pr_err("Could not register msm-smmu at %pa\n", &ioaddr);
800 		goto fail;
801 	}
802 
803 	bus_set_iommu(&platform_bus_type, &msm_iommu_ops);
804 
805 	pr_info("device mapped at %p, irq %d with %d ctx banks\n",
806 		iommu->base, iommu->irq, iommu->ncb);
807 
808 	return ret;
809 fail:
810 	clk_unprepare(iommu->clk);
811 	clk_unprepare(iommu->pclk);
812 	return ret;
813 }
814 
815 static const struct of_device_id msm_iommu_dt_match[] = {
816 	{ .compatible = "qcom,apq8064-iommu" },
817 	{}
818 };
819 
820 static int msm_iommu_remove(struct platform_device *pdev)
821 {
822 	struct msm_iommu_dev *iommu = platform_get_drvdata(pdev);
823 
824 	clk_unprepare(iommu->clk);
825 	clk_unprepare(iommu->pclk);
826 	return 0;
827 }
828 
829 static struct platform_driver msm_iommu_driver = {
830 	.driver = {
831 		.name	= "msm_iommu",
832 		.of_match_table = msm_iommu_dt_match,
833 	},
834 	.probe		= msm_iommu_probe,
835 	.remove		= msm_iommu_remove,
836 };
837 
838 static int __init msm_iommu_driver_init(void)
839 {
840 	int ret;
841 
842 	ret = platform_driver_register(&msm_iommu_driver);
843 	if (ret != 0)
844 		pr_err("Failed to register IOMMU driver\n");
845 
846 	return ret;
847 }
848 subsys_initcall(msm_iommu_driver_init);
849 
850