xref: /openbmc/linux/drivers/iommu/msm_iommu.c (revision 3557b3fd)
1 /* Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
2  *
3  * Author: Stepan Moskovchenko <stepanm@codeaurora.org>
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 and
7  * only version 2 as published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
17  * 02110-1301, USA.
18  */
19 
20 #define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
21 #include <linux/kernel.h>
22 #include <linux/init.h>
23 #include <linux/platform_device.h>
24 #include <linux/errno.h>
25 #include <linux/io.h>
26 #include <linux/io-pgtable.h>
27 #include <linux/interrupt.h>
28 #include <linux/list.h>
29 #include <linux/spinlock.h>
30 #include <linux/slab.h>
31 #include <linux/iommu.h>
32 #include <linux/clk.h>
33 #include <linux/err.h>
34 #include <linux/of_iommu.h>
35 
36 #include <asm/cacheflush.h>
37 #include <asm/sizes.h>
38 
39 #include "msm_iommu_hw-8xxx.h"
40 #include "msm_iommu.h"
41 
42 #define MRC(reg, processor, op1, crn, crm, op2)				\
43 __asm__ __volatile__ (							\
44 "   mrc   "   #processor "," #op1 ", %0,"  #crn "," #crm "," #op2 "\n"  \
45 : "=r" (reg))
46 
47 /* bitmap of the page sizes currently supported */
48 #define MSM_IOMMU_PGSIZES	(SZ_4K | SZ_64K | SZ_1M | SZ_16M)
49 
50 DEFINE_SPINLOCK(msm_iommu_lock);
51 static LIST_HEAD(qcom_iommu_devices);
52 static struct iommu_ops msm_iommu_ops;
53 
54 struct msm_priv {
55 	struct list_head list_attached;
56 	struct iommu_domain domain;
57 	struct io_pgtable_cfg	cfg;
58 	struct io_pgtable_ops	*iop;
59 	struct device		*dev;
60 	spinlock_t		pgtlock; /* pagetable lock */
61 };
62 
63 static struct msm_priv *to_msm_priv(struct iommu_domain *dom)
64 {
65 	return container_of(dom, struct msm_priv, domain);
66 }
67 
68 static int __enable_clocks(struct msm_iommu_dev *iommu)
69 {
70 	int ret;
71 
72 	ret = clk_enable(iommu->pclk);
73 	if (ret)
74 		goto fail;
75 
76 	if (iommu->clk) {
77 		ret = clk_enable(iommu->clk);
78 		if (ret)
79 			clk_disable(iommu->pclk);
80 	}
81 fail:
82 	return ret;
83 }
84 
85 static void __disable_clocks(struct msm_iommu_dev *iommu)
86 {
87 	if (iommu->clk)
88 		clk_disable(iommu->clk);
89 	clk_disable(iommu->pclk);
90 }
91 
92 static void msm_iommu_reset(void __iomem *base, int ncb)
93 {
94 	int ctx;
95 
96 	SET_RPUE(base, 0);
97 	SET_RPUEIE(base, 0);
98 	SET_ESRRESTORE(base, 0);
99 	SET_TBE(base, 0);
100 	SET_CR(base, 0);
101 	SET_SPDMBE(base, 0);
102 	SET_TESTBUSCR(base, 0);
103 	SET_TLBRSW(base, 0);
104 	SET_GLOBAL_TLBIALL(base, 0);
105 	SET_RPU_ACR(base, 0);
106 	SET_TLBLKCRWE(base, 1);
107 
108 	for (ctx = 0; ctx < ncb; ctx++) {
109 		SET_BPRCOSH(base, ctx, 0);
110 		SET_BPRCISH(base, ctx, 0);
111 		SET_BPRCNSH(base, ctx, 0);
112 		SET_BPSHCFG(base, ctx, 0);
113 		SET_BPMTCFG(base, ctx, 0);
114 		SET_ACTLR(base, ctx, 0);
115 		SET_SCTLR(base, ctx, 0);
116 		SET_FSRRESTORE(base, ctx, 0);
117 		SET_TTBR0(base, ctx, 0);
118 		SET_TTBR1(base, ctx, 0);
119 		SET_TTBCR(base, ctx, 0);
120 		SET_BFBCR(base, ctx, 0);
121 		SET_PAR(base, ctx, 0);
122 		SET_FAR(base, ctx, 0);
123 		SET_CTX_TLBIALL(base, ctx, 0);
124 		SET_TLBFLPTER(base, ctx, 0);
125 		SET_TLBSLPTER(base, ctx, 0);
126 		SET_TLBLKCR(base, ctx, 0);
127 		SET_CONTEXTIDR(base, ctx, 0);
128 	}
129 }
130 
131 static void __flush_iotlb(void *cookie)
132 {
133 	struct msm_priv *priv = cookie;
134 	struct msm_iommu_dev *iommu = NULL;
135 	struct msm_iommu_ctx_dev *master;
136 	int ret = 0;
137 
138 	list_for_each_entry(iommu, &priv->list_attached, dom_node) {
139 		ret = __enable_clocks(iommu);
140 		if (ret)
141 			goto fail;
142 
143 		list_for_each_entry(master, &iommu->ctx_list, list)
144 			SET_CTX_TLBIALL(iommu->base, master->num, 0);
145 
146 		__disable_clocks(iommu);
147 	}
148 fail:
149 	return;
150 }
151 
152 static void __flush_iotlb_range(unsigned long iova, size_t size,
153 				size_t granule, bool leaf, void *cookie)
154 {
155 	struct msm_priv *priv = cookie;
156 	struct msm_iommu_dev *iommu = NULL;
157 	struct msm_iommu_ctx_dev *master;
158 	int ret = 0;
159 	int temp_size;
160 
161 	list_for_each_entry(iommu, &priv->list_attached, dom_node) {
162 		ret = __enable_clocks(iommu);
163 		if (ret)
164 			goto fail;
165 
166 		list_for_each_entry(master, &iommu->ctx_list, list) {
167 			temp_size = size;
168 			do {
169 				iova &= TLBIVA_VA;
170 				iova |= GET_CONTEXTIDR_ASID(iommu->base,
171 							    master->num);
172 				SET_TLBIVA(iommu->base, master->num, iova);
173 				iova += granule;
174 			} while (temp_size -= granule);
175 		}
176 
177 		__disable_clocks(iommu);
178 	}
179 
180 fail:
181 	return;
182 }
183 
184 static void __flush_iotlb_sync(void *cookie)
185 {
186 	/*
187 	 * Nothing is needed here, the barrier to guarantee
188 	 * completion of the tlb sync operation is implicitly
189 	 * taken care when the iommu client does a writel before
190 	 * kick starting the other master.
191 	 */
192 }
193 
194 static const struct iommu_gather_ops msm_iommu_gather_ops = {
195 	.tlb_flush_all = __flush_iotlb,
196 	.tlb_add_flush = __flush_iotlb_range,
197 	.tlb_sync = __flush_iotlb_sync,
198 };
199 
200 static int msm_iommu_alloc_ctx(unsigned long *map, int start, int end)
201 {
202 	int idx;
203 
204 	do {
205 		idx = find_next_zero_bit(map, end, start);
206 		if (idx == end)
207 			return -ENOSPC;
208 	} while (test_and_set_bit(idx, map));
209 
210 	return idx;
211 }
212 
213 static void msm_iommu_free_ctx(unsigned long *map, int idx)
214 {
215 	clear_bit(idx, map);
216 }
217 
218 static void config_mids(struct msm_iommu_dev *iommu,
219 			struct msm_iommu_ctx_dev *master)
220 {
221 	int mid, ctx, i;
222 
223 	for (i = 0; i < master->num_mids; i++) {
224 		mid = master->mids[i];
225 		ctx = master->num;
226 
227 		SET_M2VCBR_N(iommu->base, mid, 0);
228 		SET_CBACR_N(iommu->base, ctx, 0);
229 
230 		/* Set VMID = 0 */
231 		SET_VMID(iommu->base, mid, 0);
232 
233 		/* Set the context number for that MID to this context */
234 		SET_CBNDX(iommu->base, mid, ctx);
235 
236 		/* Set MID associated with this context bank to 0*/
237 		SET_CBVMID(iommu->base, ctx, 0);
238 
239 		/* Set the ASID for TLB tagging for this context */
240 		SET_CONTEXTIDR_ASID(iommu->base, ctx, ctx);
241 
242 		/* Set security bit override to be Non-secure */
243 		SET_NSCFG(iommu->base, mid, 3);
244 	}
245 }
246 
247 static void __reset_context(void __iomem *base, int ctx)
248 {
249 	SET_BPRCOSH(base, ctx, 0);
250 	SET_BPRCISH(base, ctx, 0);
251 	SET_BPRCNSH(base, ctx, 0);
252 	SET_BPSHCFG(base, ctx, 0);
253 	SET_BPMTCFG(base, ctx, 0);
254 	SET_ACTLR(base, ctx, 0);
255 	SET_SCTLR(base, ctx, 0);
256 	SET_FSRRESTORE(base, ctx, 0);
257 	SET_TTBR0(base, ctx, 0);
258 	SET_TTBR1(base, ctx, 0);
259 	SET_TTBCR(base, ctx, 0);
260 	SET_BFBCR(base, ctx, 0);
261 	SET_PAR(base, ctx, 0);
262 	SET_FAR(base, ctx, 0);
263 	SET_CTX_TLBIALL(base, ctx, 0);
264 	SET_TLBFLPTER(base, ctx, 0);
265 	SET_TLBSLPTER(base, ctx, 0);
266 	SET_TLBLKCR(base, ctx, 0);
267 }
268 
269 static void __program_context(void __iomem *base, int ctx,
270 			      struct msm_priv *priv)
271 {
272 	__reset_context(base, ctx);
273 
274 	/* Turn on TEX Remap */
275 	SET_TRE(base, ctx, 1);
276 	SET_AFE(base, ctx, 1);
277 
278 	/* Set up HTW mode */
279 	/* TLB miss configuration: perform HTW on miss */
280 	SET_TLBMCFG(base, ctx, 0x3);
281 
282 	/* V2P configuration: HTW for access */
283 	SET_V2PCFG(base, ctx, 0x3);
284 
285 	SET_TTBCR(base, ctx, priv->cfg.arm_v7s_cfg.tcr);
286 	SET_TTBR0(base, ctx, priv->cfg.arm_v7s_cfg.ttbr[0]);
287 	SET_TTBR1(base, ctx, priv->cfg.arm_v7s_cfg.ttbr[1]);
288 
289 	/* Set prrr and nmrr */
290 	SET_PRRR(base, ctx, priv->cfg.arm_v7s_cfg.prrr);
291 	SET_NMRR(base, ctx, priv->cfg.arm_v7s_cfg.nmrr);
292 
293 	/* Invalidate the TLB for this context */
294 	SET_CTX_TLBIALL(base, ctx, 0);
295 
296 	/* Set interrupt number to "secure" interrupt */
297 	SET_IRPTNDX(base, ctx, 0);
298 
299 	/* Enable context fault interrupt */
300 	SET_CFEIE(base, ctx, 1);
301 
302 	/* Stall access on a context fault and let the handler deal with it */
303 	SET_CFCFG(base, ctx, 1);
304 
305 	/* Redirect all cacheable requests to L2 slave port. */
306 	SET_RCISH(base, ctx, 1);
307 	SET_RCOSH(base, ctx, 1);
308 	SET_RCNSH(base, ctx, 1);
309 
310 	/* Turn on BFB prefetch */
311 	SET_BFBDFE(base, ctx, 1);
312 
313 	/* Enable the MMU */
314 	SET_M(base, ctx, 1);
315 }
316 
317 static struct iommu_domain *msm_iommu_domain_alloc(unsigned type)
318 {
319 	struct msm_priv *priv;
320 
321 	if (type != IOMMU_DOMAIN_UNMANAGED)
322 		return NULL;
323 
324 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
325 	if (!priv)
326 		goto fail_nomem;
327 
328 	INIT_LIST_HEAD(&priv->list_attached);
329 
330 	priv->domain.geometry.aperture_start = 0;
331 	priv->domain.geometry.aperture_end   = (1ULL << 32) - 1;
332 	priv->domain.geometry.force_aperture = true;
333 
334 	return &priv->domain;
335 
336 fail_nomem:
337 	kfree(priv);
338 	return NULL;
339 }
340 
341 static void msm_iommu_domain_free(struct iommu_domain *domain)
342 {
343 	struct msm_priv *priv;
344 	unsigned long flags;
345 
346 	spin_lock_irqsave(&msm_iommu_lock, flags);
347 	priv = to_msm_priv(domain);
348 	kfree(priv);
349 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
350 }
351 
352 static int msm_iommu_domain_config(struct msm_priv *priv)
353 {
354 	spin_lock_init(&priv->pgtlock);
355 
356 	priv->cfg = (struct io_pgtable_cfg) {
357 		.quirks = IO_PGTABLE_QUIRK_TLBI_ON_MAP,
358 		.pgsize_bitmap = msm_iommu_ops.pgsize_bitmap,
359 		.ias = 32,
360 		.oas = 32,
361 		.tlb = &msm_iommu_gather_ops,
362 		.iommu_dev = priv->dev,
363 	};
364 
365 	priv->iop = alloc_io_pgtable_ops(ARM_V7S, &priv->cfg, priv);
366 	if (!priv->iop) {
367 		dev_err(priv->dev, "Failed to allocate pgtable\n");
368 		return -EINVAL;
369 	}
370 
371 	msm_iommu_ops.pgsize_bitmap = priv->cfg.pgsize_bitmap;
372 
373 	return 0;
374 }
375 
376 /* Must be called under msm_iommu_lock */
377 static struct msm_iommu_dev *find_iommu_for_dev(struct device *dev)
378 {
379 	struct msm_iommu_dev *iommu, *ret = NULL;
380 	struct msm_iommu_ctx_dev *master;
381 
382 	list_for_each_entry(iommu, &qcom_iommu_devices, dev_node) {
383 		master = list_first_entry(&iommu->ctx_list,
384 					  struct msm_iommu_ctx_dev,
385 					  list);
386 		if (master->of_node == dev->of_node) {
387 			ret = iommu;
388 			break;
389 		}
390 	}
391 
392 	return ret;
393 }
394 
395 static int msm_iommu_add_device(struct device *dev)
396 {
397 	struct msm_iommu_dev *iommu;
398 	struct iommu_group *group;
399 	unsigned long flags;
400 
401 	spin_lock_irqsave(&msm_iommu_lock, flags);
402 	iommu = find_iommu_for_dev(dev);
403 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
404 
405 	if (iommu)
406 		iommu_device_link(&iommu->iommu, dev);
407 	else
408 		return -ENODEV;
409 
410 	group = iommu_group_get_for_dev(dev);
411 	if (IS_ERR(group))
412 		return PTR_ERR(group);
413 
414 	iommu_group_put(group);
415 
416 	return 0;
417 }
418 
419 static void msm_iommu_remove_device(struct device *dev)
420 {
421 	struct msm_iommu_dev *iommu;
422 	unsigned long flags;
423 
424 	spin_lock_irqsave(&msm_iommu_lock, flags);
425 	iommu = find_iommu_for_dev(dev);
426 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
427 
428 	if (iommu)
429 		iommu_device_unlink(&iommu->iommu, dev);
430 
431 	iommu_group_remove_device(dev);
432 }
433 
434 static int msm_iommu_attach_dev(struct iommu_domain *domain, struct device *dev)
435 {
436 	int ret = 0;
437 	unsigned long flags;
438 	struct msm_iommu_dev *iommu;
439 	struct msm_priv *priv = to_msm_priv(domain);
440 	struct msm_iommu_ctx_dev *master;
441 
442 	priv->dev = dev;
443 	msm_iommu_domain_config(priv);
444 
445 	spin_lock_irqsave(&msm_iommu_lock, flags);
446 	list_for_each_entry(iommu, &qcom_iommu_devices, dev_node) {
447 		master = list_first_entry(&iommu->ctx_list,
448 					  struct msm_iommu_ctx_dev,
449 					  list);
450 		if (master->of_node == dev->of_node) {
451 			ret = __enable_clocks(iommu);
452 			if (ret)
453 				goto fail;
454 
455 			list_for_each_entry(master, &iommu->ctx_list, list) {
456 				if (master->num) {
457 					dev_err(dev, "domain already attached");
458 					ret = -EEXIST;
459 					goto fail;
460 				}
461 				master->num =
462 					msm_iommu_alloc_ctx(iommu->context_map,
463 							    0, iommu->ncb);
464 				if (IS_ERR_VALUE(master->num)) {
465 					ret = -ENODEV;
466 					goto fail;
467 				}
468 				config_mids(iommu, master);
469 				__program_context(iommu->base, master->num,
470 						  priv);
471 			}
472 			__disable_clocks(iommu);
473 			list_add(&iommu->dom_node, &priv->list_attached);
474 		}
475 	}
476 
477 fail:
478 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
479 
480 	return ret;
481 }
482 
483 static void msm_iommu_detach_dev(struct iommu_domain *domain,
484 				 struct device *dev)
485 {
486 	struct msm_priv *priv = to_msm_priv(domain);
487 	unsigned long flags;
488 	struct msm_iommu_dev *iommu;
489 	struct msm_iommu_ctx_dev *master;
490 	int ret;
491 
492 	free_io_pgtable_ops(priv->iop);
493 
494 	spin_lock_irqsave(&msm_iommu_lock, flags);
495 	list_for_each_entry(iommu, &priv->list_attached, dom_node) {
496 		ret = __enable_clocks(iommu);
497 		if (ret)
498 			goto fail;
499 
500 		list_for_each_entry(master, &iommu->ctx_list, list) {
501 			msm_iommu_free_ctx(iommu->context_map, master->num);
502 			__reset_context(iommu->base, master->num);
503 		}
504 		__disable_clocks(iommu);
505 	}
506 fail:
507 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
508 }
509 
510 static int msm_iommu_map(struct iommu_domain *domain, unsigned long iova,
511 			 phys_addr_t pa, size_t len, int prot)
512 {
513 	struct msm_priv *priv = to_msm_priv(domain);
514 	unsigned long flags;
515 	int ret;
516 
517 	spin_lock_irqsave(&priv->pgtlock, flags);
518 	ret = priv->iop->map(priv->iop, iova, pa, len, prot);
519 	spin_unlock_irqrestore(&priv->pgtlock, flags);
520 
521 	return ret;
522 }
523 
524 static size_t msm_iommu_unmap(struct iommu_domain *domain, unsigned long iova,
525 			      size_t len)
526 {
527 	struct msm_priv *priv = to_msm_priv(domain);
528 	unsigned long flags;
529 
530 	spin_lock_irqsave(&priv->pgtlock, flags);
531 	len = priv->iop->unmap(priv->iop, iova, len);
532 	spin_unlock_irqrestore(&priv->pgtlock, flags);
533 
534 	return len;
535 }
536 
537 static phys_addr_t msm_iommu_iova_to_phys(struct iommu_domain *domain,
538 					  dma_addr_t va)
539 {
540 	struct msm_priv *priv;
541 	struct msm_iommu_dev *iommu;
542 	struct msm_iommu_ctx_dev *master;
543 	unsigned int par;
544 	unsigned long flags;
545 	phys_addr_t ret = 0;
546 
547 	spin_lock_irqsave(&msm_iommu_lock, flags);
548 
549 	priv = to_msm_priv(domain);
550 	iommu = list_first_entry(&priv->list_attached,
551 				 struct msm_iommu_dev, dom_node);
552 
553 	if (list_empty(&iommu->ctx_list))
554 		goto fail;
555 
556 	master = list_first_entry(&iommu->ctx_list,
557 				  struct msm_iommu_ctx_dev, list);
558 	if (!master)
559 		goto fail;
560 
561 	ret = __enable_clocks(iommu);
562 	if (ret)
563 		goto fail;
564 
565 	/* Invalidate context TLB */
566 	SET_CTX_TLBIALL(iommu->base, master->num, 0);
567 	SET_V2PPR(iommu->base, master->num, va & V2Pxx_VA);
568 
569 	par = GET_PAR(iommu->base, master->num);
570 
571 	/* We are dealing with a supersection */
572 	if (GET_NOFAULT_SS(iommu->base, master->num))
573 		ret = (par & 0xFF000000) | (va & 0x00FFFFFF);
574 	else	/* Upper 20 bits from PAR, lower 12 from VA */
575 		ret = (par & 0xFFFFF000) | (va & 0x00000FFF);
576 
577 	if (GET_FAULT(iommu->base, master->num))
578 		ret = 0;
579 
580 	__disable_clocks(iommu);
581 fail:
582 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
583 	return ret;
584 }
585 
586 static bool msm_iommu_capable(enum iommu_cap cap)
587 {
588 	return false;
589 }
590 
591 static void print_ctx_regs(void __iomem *base, int ctx)
592 {
593 	unsigned int fsr = GET_FSR(base, ctx);
594 	pr_err("FAR    = %08x    PAR    = %08x\n",
595 	       GET_FAR(base, ctx), GET_PAR(base, ctx));
596 	pr_err("FSR    = %08x [%s%s%s%s%s%s%s%s%s%s]\n", fsr,
597 			(fsr & 0x02) ? "TF " : "",
598 			(fsr & 0x04) ? "AFF " : "",
599 			(fsr & 0x08) ? "APF " : "",
600 			(fsr & 0x10) ? "TLBMF " : "",
601 			(fsr & 0x20) ? "HTWDEEF " : "",
602 			(fsr & 0x40) ? "HTWSEEF " : "",
603 			(fsr & 0x80) ? "MHF " : "",
604 			(fsr & 0x10000) ? "SL " : "",
605 			(fsr & 0x40000000) ? "SS " : "",
606 			(fsr & 0x80000000) ? "MULTI " : "");
607 
608 	pr_err("FSYNR0 = %08x    FSYNR1 = %08x\n",
609 	       GET_FSYNR0(base, ctx), GET_FSYNR1(base, ctx));
610 	pr_err("TTBR0  = %08x    TTBR1  = %08x\n",
611 	       GET_TTBR0(base, ctx), GET_TTBR1(base, ctx));
612 	pr_err("SCTLR  = %08x    ACTLR  = %08x\n",
613 	       GET_SCTLR(base, ctx), GET_ACTLR(base, ctx));
614 }
615 
616 static void insert_iommu_master(struct device *dev,
617 				struct msm_iommu_dev **iommu,
618 				struct of_phandle_args *spec)
619 {
620 	struct msm_iommu_ctx_dev *master = dev->archdata.iommu;
621 	int sid;
622 
623 	if (list_empty(&(*iommu)->ctx_list)) {
624 		master = kzalloc(sizeof(*master), GFP_ATOMIC);
625 		master->of_node = dev->of_node;
626 		list_add(&master->list, &(*iommu)->ctx_list);
627 		dev->archdata.iommu = master;
628 	}
629 
630 	for (sid = 0; sid < master->num_mids; sid++)
631 		if (master->mids[sid] == spec->args[0]) {
632 			dev_warn(dev, "Stream ID 0x%hx repeated; ignoring\n",
633 				 sid);
634 			return;
635 		}
636 
637 	master->mids[master->num_mids++] = spec->args[0];
638 }
639 
640 static int qcom_iommu_of_xlate(struct device *dev,
641 			       struct of_phandle_args *spec)
642 {
643 	struct msm_iommu_dev *iommu;
644 	unsigned long flags;
645 	int ret = 0;
646 
647 	spin_lock_irqsave(&msm_iommu_lock, flags);
648 	list_for_each_entry(iommu, &qcom_iommu_devices, dev_node)
649 		if (iommu->dev->of_node == spec->np)
650 			break;
651 
652 	if (!iommu || iommu->dev->of_node != spec->np) {
653 		ret = -ENODEV;
654 		goto fail;
655 	}
656 
657 	insert_iommu_master(dev, &iommu, spec);
658 fail:
659 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
660 
661 	return ret;
662 }
663 
664 irqreturn_t msm_iommu_fault_handler(int irq, void *dev_id)
665 {
666 	struct msm_iommu_dev *iommu = dev_id;
667 	unsigned int fsr;
668 	int i, ret;
669 
670 	spin_lock(&msm_iommu_lock);
671 
672 	if (!iommu) {
673 		pr_err("Invalid device ID in context interrupt handler\n");
674 		goto fail;
675 	}
676 
677 	pr_err("Unexpected IOMMU page fault!\n");
678 	pr_err("base = %08x\n", (unsigned int)iommu->base);
679 
680 	ret = __enable_clocks(iommu);
681 	if (ret)
682 		goto fail;
683 
684 	for (i = 0; i < iommu->ncb; i++) {
685 		fsr = GET_FSR(iommu->base, i);
686 		if (fsr) {
687 			pr_err("Fault occurred in context %d.\n", i);
688 			pr_err("Interesting registers:\n");
689 			print_ctx_regs(iommu->base, i);
690 			SET_FSR(iommu->base, i, 0x4000000F);
691 		}
692 	}
693 	__disable_clocks(iommu);
694 fail:
695 	spin_unlock(&msm_iommu_lock);
696 	return 0;
697 }
698 
699 static struct iommu_ops msm_iommu_ops = {
700 	.capable = msm_iommu_capable,
701 	.domain_alloc = msm_iommu_domain_alloc,
702 	.domain_free = msm_iommu_domain_free,
703 	.attach_dev = msm_iommu_attach_dev,
704 	.detach_dev = msm_iommu_detach_dev,
705 	.map = msm_iommu_map,
706 	.unmap = msm_iommu_unmap,
707 	.iova_to_phys = msm_iommu_iova_to_phys,
708 	.add_device = msm_iommu_add_device,
709 	.remove_device = msm_iommu_remove_device,
710 	.device_group = generic_device_group,
711 	.pgsize_bitmap = MSM_IOMMU_PGSIZES,
712 	.of_xlate = qcom_iommu_of_xlate,
713 };
714 
715 static int msm_iommu_probe(struct platform_device *pdev)
716 {
717 	struct resource *r;
718 	resource_size_t ioaddr;
719 	struct msm_iommu_dev *iommu;
720 	int ret, par, val;
721 
722 	iommu = devm_kzalloc(&pdev->dev, sizeof(*iommu), GFP_KERNEL);
723 	if (!iommu)
724 		return -ENODEV;
725 
726 	iommu->dev = &pdev->dev;
727 	INIT_LIST_HEAD(&iommu->ctx_list);
728 
729 	iommu->pclk = devm_clk_get(iommu->dev, "smmu_pclk");
730 	if (IS_ERR(iommu->pclk)) {
731 		dev_err(iommu->dev, "could not get smmu_pclk\n");
732 		return PTR_ERR(iommu->pclk);
733 	}
734 
735 	ret = clk_prepare(iommu->pclk);
736 	if (ret) {
737 		dev_err(iommu->dev, "could not prepare smmu_pclk\n");
738 		return ret;
739 	}
740 
741 	iommu->clk = devm_clk_get(iommu->dev, "iommu_clk");
742 	if (IS_ERR(iommu->clk)) {
743 		dev_err(iommu->dev, "could not get iommu_clk\n");
744 		clk_unprepare(iommu->pclk);
745 		return PTR_ERR(iommu->clk);
746 	}
747 
748 	ret = clk_prepare(iommu->clk);
749 	if (ret) {
750 		dev_err(iommu->dev, "could not prepare iommu_clk\n");
751 		clk_unprepare(iommu->pclk);
752 		return ret;
753 	}
754 
755 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
756 	iommu->base = devm_ioremap_resource(iommu->dev, r);
757 	if (IS_ERR(iommu->base)) {
758 		dev_err(iommu->dev, "could not get iommu base\n");
759 		ret = PTR_ERR(iommu->base);
760 		goto fail;
761 	}
762 	ioaddr = r->start;
763 
764 	iommu->irq = platform_get_irq(pdev, 0);
765 	if (iommu->irq < 0) {
766 		dev_err(iommu->dev, "could not get iommu irq\n");
767 		ret = -ENODEV;
768 		goto fail;
769 	}
770 
771 	ret = of_property_read_u32(iommu->dev->of_node, "qcom,ncb", &val);
772 	if (ret) {
773 		dev_err(iommu->dev, "could not get ncb\n");
774 		goto fail;
775 	}
776 	iommu->ncb = val;
777 
778 	msm_iommu_reset(iommu->base, iommu->ncb);
779 	SET_M(iommu->base, 0, 1);
780 	SET_PAR(iommu->base, 0, 0);
781 	SET_V2PCFG(iommu->base, 0, 1);
782 	SET_V2PPR(iommu->base, 0, 0);
783 	par = GET_PAR(iommu->base, 0);
784 	SET_V2PCFG(iommu->base, 0, 0);
785 	SET_M(iommu->base, 0, 0);
786 
787 	if (!par) {
788 		pr_err("Invalid PAR value detected\n");
789 		ret = -ENODEV;
790 		goto fail;
791 	}
792 
793 	ret = devm_request_threaded_irq(iommu->dev, iommu->irq, NULL,
794 					msm_iommu_fault_handler,
795 					IRQF_ONESHOT | IRQF_SHARED,
796 					"msm_iommu_secure_irpt_handler",
797 					iommu);
798 	if (ret) {
799 		pr_err("Request IRQ %d failed with ret=%d\n", iommu->irq, ret);
800 		goto fail;
801 	}
802 
803 	list_add(&iommu->dev_node, &qcom_iommu_devices);
804 
805 	ret = iommu_device_sysfs_add(&iommu->iommu, iommu->dev, NULL,
806 				     "msm-smmu.%pa", &ioaddr);
807 	if (ret) {
808 		pr_err("Could not add msm-smmu at %pa to sysfs\n", &ioaddr);
809 		goto fail;
810 	}
811 
812 	iommu_device_set_ops(&iommu->iommu, &msm_iommu_ops);
813 	iommu_device_set_fwnode(&iommu->iommu, &pdev->dev.of_node->fwnode);
814 
815 	ret = iommu_device_register(&iommu->iommu);
816 	if (ret) {
817 		pr_err("Could not register msm-smmu at %pa\n", &ioaddr);
818 		goto fail;
819 	}
820 
821 	bus_set_iommu(&platform_bus_type, &msm_iommu_ops);
822 
823 	pr_info("device mapped at %p, irq %d with %d ctx banks\n",
824 		iommu->base, iommu->irq, iommu->ncb);
825 
826 	return ret;
827 fail:
828 	clk_unprepare(iommu->clk);
829 	clk_unprepare(iommu->pclk);
830 	return ret;
831 }
832 
833 static const struct of_device_id msm_iommu_dt_match[] = {
834 	{ .compatible = "qcom,apq8064-iommu" },
835 	{}
836 };
837 
838 static int msm_iommu_remove(struct platform_device *pdev)
839 {
840 	struct msm_iommu_dev *iommu = platform_get_drvdata(pdev);
841 
842 	clk_unprepare(iommu->clk);
843 	clk_unprepare(iommu->pclk);
844 	return 0;
845 }
846 
847 static struct platform_driver msm_iommu_driver = {
848 	.driver = {
849 		.name	= "msm_iommu",
850 		.of_match_table = msm_iommu_dt_match,
851 	},
852 	.probe		= msm_iommu_probe,
853 	.remove		= msm_iommu_remove,
854 };
855 
856 static int __init msm_iommu_driver_init(void)
857 {
858 	int ret;
859 
860 	ret = platform_driver_register(&msm_iommu_driver);
861 	if (ret != 0)
862 		pr_err("Failed to register IOMMU driver\n");
863 
864 	return ret;
865 }
866 subsys_initcall(msm_iommu_driver_init);
867 
868