xref: /linux/drivers/iommu/msm_iommu.c (revision bfd5bb6f90af092aa345b15cd78143956a13c2a8)
1 /* Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
2  *
3  * This program is free software; you can redistribute it and/or modify
4  * it under the terms of the GNU General Public License version 2 and
5  * only version 2 as published by the Free Software Foundation.
6  *
7  * This program is distributed in the hope that it will be useful,
8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
10  * GNU General Public License for more details.
11  *
12  * You should have received a copy of the GNU General Public License
13  * along with this program; if not, write to the Free Software
14  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
15  * 02110-1301, USA.
16  */
17 
18 #define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/platform_device.h>
22 #include <linux/errno.h>
23 #include <linux/io.h>
24 #include <linux/interrupt.h>
25 #include <linux/list.h>
26 #include <linux/spinlock.h>
27 #include <linux/slab.h>
28 #include <linux/iommu.h>
29 #include <linux/clk.h>
30 #include <linux/err.h>
31 #include <linux/of_iommu.h>
32 
33 #include <asm/cacheflush.h>
34 #include <asm/sizes.h>
35 
36 #include "msm_iommu_hw-8xxx.h"
37 #include "msm_iommu.h"
38 #include "io-pgtable.h"
39 
40 #define MRC(reg, processor, op1, crn, crm, op2)				\
41 __asm__ __volatile__ (							\
42 "   mrc   "   #processor "," #op1 ", %0,"  #crn "," #crm "," #op2 "\n"  \
43 : "=r" (reg))
44 
45 /* bitmap of the page sizes currently supported */
46 #define MSM_IOMMU_PGSIZES	(SZ_4K | SZ_64K | SZ_1M | SZ_16M)
47 
48 DEFINE_SPINLOCK(msm_iommu_lock);
49 static LIST_HEAD(qcom_iommu_devices);
50 static struct iommu_ops msm_iommu_ops;
51 
52 struct msm_priv {
53 	struct list_head list_attached;
54 	struct iommu_domain domain;
55 	struct io_pgtable_cfg	cfg;
56 	struct io_pgtable_ops	*iop;
57 	struct device		*dev;
58 	spinlock_t		pgtlock; /* pagetable lock */
59 };
60 
61 static struct msm_priv *to_msm_priv(struct iommu_domain *dom)
62 {
63 	return container_of(dom, struct msm_priv, domain);
64 }
65 
66 static int __enable_clocks(struct msm_iommu_dev *iommu)
67 {
68 	int ret;
69 
70 	ret = clk_enable(iommu->pclk);
71 	if (ret)
72 		goto fail;
73 
74 	if (iommu->clk) {
75 		ret = clk_enable(iommu->clk);
76 		if (ret)
77 			clk_disable(iommu->pclk);
78 	}
79 fail:
80 	return ret;
81 }
82 
83 static void __disable_clocks(struct msm_iommu_dev *iommu)
84 {
85 	if (iommu->clk)
86 		clk_disable(iommu->clk);
87 	clk_disable(iommu->pclk);
88 }
89 
90 static void msm_iommu_reset(void __iomem *base, int ncb)
91 {
92 	int ctx;
93 
94 	SET_RPUE(base, 0);
95 	SET_RPUEIE(base, 0);
96 	SET_ESRRESTORE(base, 0);
97 	SET_TBE(base, 0);
98 	SET_CR(base, 0);
99 	SET_SPDMBE(base, 0);
100 	SET_TESTBUSCR(base, 0);
101 	SET_TLBRSW(base, 0);
102 	SET_GLOBAL_TLBIALL(base, 0);
103 	SET_RPU_ACR(base, 0);
104 	SET_TLBLKCRWE(base, 1);
105 
106 	for (ctx = 0; ctx < ncb; ctx++) {
107 		SET_BPRCOSH(base, ctx, 0);
108 		SET_BPRCISH(base, ctx, 0);
109 		SET_BPRCNSH(base, ctx, 0);
110 		SET_BPSHCFG(base, ctx, 0);
111 		SET_BPMTCFG(base, ctx, 0);
112 		SET_ACTLR(base, ctx, 0);
113 		SET_SCTLR(base, ctx, 0);
114 		SET_FSRRESTORE(base, ctx, 0);
115 		SET_TTBR0(base, ctx, 0);
116 		SET_TTBR1(base, ctx, 0);
117 		SET_TTBCR(base, ctx, 0);
118 		SET_BFBCR(base, ctx, 0);
119 		SET_PAR(base, ctx, 0);
120 		SET_FAR(base, ctx, 0);
121 		SET_CTX_TLBIALL(base, ctx, 0);
122 		SET_TLBFLPTER(base, ctx, 0);
123 		SET_TLBSLPTER(base, ctx, 0);
124 		SET_TLBLKCR(base, ctx, 0);
125 		SET_CONTEXTIDR(base, ctx, 0);
126 	}
127 }
128 
129 static void __flush_iotlb(void *cookie)
130 {
131 	struct msm_priv *priv = cookie;
132 	struct msm_iommu_dev *iommu = NULL;
133 	struct msm_iommu_ctx_dev *master;
134 	int ret = 0;
135 
136 	list_for_each_entry(iommu, &priv->list_attached, dom_node) {
137 		ret = __enable_clocks(iommu);
138 		if (ret)
139 			goto fail;
140 
141 		list_for_each_entry(master, &iommu->ctx_list, list)
142 			SET_CTX_TLBIALL(iommu->base, master->num, 0);
143 
144 		__disable_clocks(iommu);
145 	}
146 fail:
147 	return;
148 }
149 
150 static void __flush_iotlb_range(unsigned long iova, size_t size,
151 				size_t granule, bool leaf, void *cookie)
152 {
153 	struct msm_priv *priv = cookie;
154 	struct msm_iommu_dev *iommu = NULL;
155 	struct msm_iommu_ctx_dev *master;
156 	int ret = 0;
157 	int temp_size;
158 
159 	list_for_each_entry(iommu, &priv->list_attached, dom_node) {
160 		ret = __enable_clocks(iommu);
161 		if (ret)
162 			goto fail;
163 
164 		list_for_each_entry(master, &iommu->ctx_list, list) {
165 			temp_size = size;
166 			do {
167 				iova &= TLBIVA_VA;
168 				iova |= GET_CONTEXTIDR_ASID(iommu->base,
169 							    master->num);
170 				SET_TLBIVA(iommu->base, master->num, iova);
171 				iova += granule;
172 			} while (temp_size -= granule);
173 		}
174 
175 		__disable_clocks(iommu);
176 	}
177 
178 fail:
179 	return;
180 }
181 
182 static void __flush_iotlb_sync(void *cookie)
183 {
184 	/*
185 	 * Nothing is needed here, the barrier to guarantee
186 	 * completion of the tlb sync operation is implicitly
187 	 * taken care when the iommu client does a writel before
188 	 * kick starting the other master.
189 	 */
190 }
191 
192 static const struct iommu_gather_ops msm_iommu_gather_ops = {
193 	.tlb_flush_all = __flush_iotlb,
194 	.tlb_add_flush = __flush_iotlb_range,
195 	.tlb_sync = __flush_iotlb_sync,
196 };
197 
198 static int msm_iommu_alloc_ctx(unsigned long *map, int start, int end)
199 {
200 	int idx;
201 
202 	do {
203 		idx = find_next_zero_bit(map, end, start);
204 		if (idx == end)
205 			return -ENOSPC;
206 	} while (test_and_set_bit(idx, map));
207 
208 	return idx;
209 }
210 
211 static void msm_iommu_free_ctx(unsigned long *map, int idx)
212 {
213 	clear_bit(idx, map);
214 }
215 
216 static void config_mids(struct msm_iommu_dev *iommu,
217 			struct msm_iommu_ctx_dev *master)
218 {
219 	int mid, ctx, i;
220 
221 	for (i = 0; i < master->num_mids; i++) {
222 		mid = master->mids[i];
223 		ctx = master->num;
224 
225 		SET_M2VCBR_N(iommu->base, mid, 0);
226 		SET_CBACR_N(iommu->base, ctx, 0);
227 
228 		/* Set VMID = 0 */
229 		SET_VMID(iommu->base, mid, 0);
230 
231 		/* Set the context number for that MID to this context */
232 		SET_CBNDX(iommu->base, mid, ctx);
233 
234 		/* Set MID associated with this context bank to 0*/
235 		SET_CBVMID(iommu->base, ctx, 0);
236 
237 		/* Set the ASID for TLB tagging for this context */
238 		SET_CONTEXTIDR_ASID(iommu->base, ctx, ctx);
239 
240 		/* Set security bit override to be Non-secure */
241 		SET_NSCFG(iommu->base, mid, 3);
242 	}
243 }
244 
245 static void __reset_context(void __iomem *base, int ctx)
246 {
247 	SET_BPRCOSH(base, ctx, 0);
248 	SET_BPRCISH(base, ctx, 0);
249 	SET_BPRCNSH(base, ctx, 0);
250 	SET_BPSHCFG(base, ctx, 0);
251 	SET_BPMTCFG(base, ctx, 0);
252 	SET_ACTLR(base, ctx, 0);
253 	SET_SCTLR(base, ctx, 0);
254 	SET_FSRRESTORE(base, ctx, 0);
255 	SET_TTBR0(base, ctx, 0);
256 	SET_TTBR1(base, ctx, 0);
257 	SET_TTBCR(base, ctx, 0);
258 	SET_BFBCR(base, ctx, 0);
259 	SET_PAR(base, ctx, 0);
260 	SET_FAR(base, ctx, 0);
261 	SET_CTX_TLBIALL(base, ctx, 0);
262 	SET_TLBFLPTER(base, ctx, 0);
263 	SET_TLBSLPTER(base, ctx, 0);
264 	SET_TLBLKCR(base, ctx, 0);
265 }
266 
267 static void __program_context(void __iomem *base, int ctx,
268 			      struct msm_priv *priv)
269 {
270 	__reset_context(base, ctx);
271 
272 	/* Turn on TEX Remap */
273 	SET_TRE(base, ctx, 1);
274 	SET_AFE(base, ctx, 1);
275 
276 	/* Set up HTW mode */
277 	/* TLB miss configuration: perform HTW on miss */
278 	SET_TLBMCFG(base, ctx, 0x3);
279 
280 	/* V2P configuration: HTW for access */
281 	SET_V2PCFG(base, ctx, 0x3);
282 
283 	SET_TTBCR(base, ctx, priv->cfg.arm_v7s_cfg.tcr);
284 	SET_TTBR0(base, ctx, priv->cfg.arm_v7s_cfg.ttbr[0]);
285 	SET_TTBR1(base, ctx, priv->cfg.arm_v7s_cfg.ttbr[1]);
286 
287 	/* Set prrr and nmrr */
288 	SET_PRRR(base, ctx, priv->cfg.arm_v7s_cfg.prrr);
289 	SET_NMRR(base, ctx, priv->cfg.arm_v7s_cfg.nmrr);
290 
291 	/* Invalidate the TLB for this context */
292 	SET_CTX_TLBIALL(base, ctx, 0);
293 
294 	/* Set interrupt number to "secure" interrupt */
295 	SET_IRPTNDX(base, ctx, 0);
296 
297 	/* Enable context fault interrupt */
298 	SET_CFEIE(base, ctx, 1);
299 
300 	/* Stall access on a context fault and let the handler deal with it */
301 	SET_CFCFG(base, ctx, 1);
302 
303 	/* Redirect all cacheable requests to L2 slave port. */
304 	SET_RCISH(base, ctx, 1);
305 	SET_RCOSH(base, ctx, 1);
306 	SET_RCNSH(base, ctx, 1);
307 
308 	/* Turn on BFB prefetch */
309 	SET_BFBDFE(base, ctx, 1);
310 
311 	/* Enable the MMU */
312 	SET_M(base, ctx, 1);
313 }
314 
315 static struct iommu_domain *msm_iommu_domain_alloc(unsigned type)
316 {
317 	struct msm_priv *priv;
318 
319 	if (type != IOMMU_DOMAIN_UNMANAGED)
320 		return NULL;
321 
322 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
323 	if (!priv)
324 		goto fail_nomem;
325 
326 	INIT_LIST_HEAD(&priv->list_attached);
327 
328 	priv->domain.geometry.aperture_start = 0;
329 	priv->domain.geometry.aperture_end   = (1ULL << 32) - 1;
330 	priv->domain.geometry.force_aperture = true;
331 
332 	return &priv->domain;
333 
334 fail_nomem:
335 	kfree(priv);
336 	return NULL;
337 }
338 
339 static void msm_iommu_domain_free(struct iommu_domain *domain)
340 {
341 	struct msm_priv *priv;
342 	unsigned long flags;
343 
344 	spin_lock_irqsave(&msm_iommu_lock, flags);
345 	priv = to_msm_priv(domain);
346 	kfree(priv);
347 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
348 }
349 
350 static int msm_iommu_domain_config(struct msm_priv *priv)
351 {
352 	spin_lock_init(&priv->pgtlock);
353 
354 	priv->cfg = (struct io_pgtable_cfg) {
355 		.quirks = IO_PGTABLE_QUIRK_TLBI_ON_MAP,
356 		.pgsize_bitmap = msm_iommu_ops.pgsize_bitmap,
357 		.ias = 32,
358 		.oas = 32,
359 		.tlb = &msm_iommu_gather_ops,
360 		.iommu_dev = priv->dev,
361 	};
362 
363 	priv->iop = alloc_io_pgtable_ops(ARM_V7S, &priv->cfg, priv);
364 	if (!priv->iop) {
365 		dev_err(priv->dev, "Failed to allocate pgtable\n");
366 		return -EINVAL;
367 	}
368 
369 	msm_iommu_ops.pgsize_bitmap = priv->cfg.pgsize_bitmap;
370 
371 	return 0;
372 }
373 
374 /* Must be called under msm_iommu_lock */
375 static struct msm_iommu_dev *find_iommu_for_dev(struct device *dev)
376 {
377 	struct msm_iommu_dev *iommu, *ret = NULL;
378 	struct msm_iommu_ctx_dev *master;
379 
380 	list_for_each_entry(iommu, &qcom_iommu_devices, dev_node) {
381 		master = list_first_entry(&iommu->ctx_list,
382 					  struct msm_iommu_ctx_dev,
383 					  list);
384 		if (master->of_node == dev->of_node) {
385 			ret = iommu;
386 			break;
387 		}
388 	}
389 
390 	return ret;
391 }
392 
393 static int msm_iommu_add_device(struct device *dev)
394 {
395 	struct msm_iommu_dev *iommu;
396 	struct iommu_group *group;
397 	unsigned long flags;
398 	int ret = 0;
399 
400 	spin_lock_irqsave(&msm_iommu_lock, flags);
401 
402 	iommu = find_iommu_for_dev(dev);
403 	if (iommu)
404 		iommu_device_link(&iommu->iommu, dev);
405 	else
406 		ret = -ENODEV;
407 
408 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
409 
410 	if (ret)
411 		return ret;
412 
413 	group = iommu_group_get_for_dev(dev);
414 	if (IS_ERR(group))
415 		return PTR_ERR(group);
416 
417 	iommu_group_put(group);
418 
419 	return 0;
420 }
421 
422 static void msm_iommu_remove_device(struct device *dev)
423 {
424 	struct msm_iommu_dev *iommu;
425 	unsigned long flags;
426 
427 	spin_lock_irqsave(&msm_iommu_lock, flags);
428 
429 	iommu = find_iommu_for_dev(dev);
430 	if (iommu)
431 		iommu_device_unlink(&iommu->iommu, dev);
432 
433 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
434 
435 	iommu_group_remove_device(dev);
436 }
437 
438 static int msm_iommu_attach_dev(struct iommu_domain *domain, struct device *dev)
439 {
440 	int ret = 0;
441 	unsigned long flags;
442 	struct msm_iommu_dev *iommu;
443 	struct msm_priv *priv = to_msm_priv(domain);
444 	struct msm_iommu_ctx_dev *master;
445 
446 	priv->dev = dev;
447 	msm_iommu_domain_config(priv);
448 
449 	spin_lock_irqsave(&msm_iommu_lock, flags);
450 	list_for_each_entry(iommu, &qcom_iommu_devices, dev_node) {
451 		master = list_first_entry(&iommu->ctx_list,
452 					  struct msm_iommu_ctx_dev,
453 					  list);
454 		if (master->of_node == dev->of_node) {
455 			ret = __enable_clocks(iommu);
456 			if (ret)
457 				goto fail;
458 
459 			list_for_each_entry(master, &iommu->ctx_list, list) {
460 				if (master->num) {
461 					dev_err(dev, "domain already attached");
462 					ret = -EEXIST;
463 					goto fail;
464 				}
465 				master->num =
466 					msm_iommu_alloc_ctx(iommu->context_map,
467 							    0, iommu->ncb);
468 					if (IS_ERR_VALUE(master->num)) {
469 						ret = -ENODEV;
470 						goto fail;
471 					}
472 				config_mids(iommu, master);
473 				__program_context(iommu->base, master->num,
474 						  priv);
475 			}
476 			__disable_clocks(iommu);
477 			list_add(&iommu->dom_node, &priv->list_attached);
478 		}
479 	}
480 
481 fail:
482 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
483 
484 	return ret;
485 }
486 
487 static void msm_iommu_detach_dev(struct iommu_domain *domain,
488 				 struct device *dev)
489 {
490 	struct msm_priv *priv = to_msm_priv(domain);
491 	unsigned long flags;
492 	struct msm_iommu_dev *iommu;
493 	struct msm_iommu_ctx_dev *master;
494 	int ret;
495 
496 	free_io_pgtable_ops(priv->iop);
497 
498 	spin_lock_irqsave(&msm_iommu_lock, flags);
499 	list_for_each_entry(iommu, &priv->list_attached, dom_node) {
500 		ret = __enable_clocks(iommu);
501 		if (ret)
502 			goto fail;
503 
504 		list_for_each_entry(master, &iommu->ctx_list, list) {
505 			msm_iommu_free_ctx(iommu->context_map, master->num);
506 			__reset_context(iommu->base, master->num);
507 		}
508 		__disable_clocks(iommu);
509 	}
510 fail:
511 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
512 }
513 
514 static int msm_iommu_map(struct iommu_domain *domain, unsigned long iova,
515 			 phys_addr_t pa, size_t len, int prot)
516 {
517 	struct msm_priv *priv = to_msm_priv(domain);
518 	unsigned long flags;
519 	int ret;
520 
521 	spin_lock_irqsave(&priv->pgtlock, flags);
522 	ret = priv->iop->map(priv->iop, iova, pa, len, prot);
523 	spin_unlock_irqrestore(&priv->pgtlock, flags);
524 
525 	return ret;
526 }
527 
528 static size_t msm_iommu_unmap(struct iommu_domain *domain, unsigned long iova,
529 			      size_t len)
530 {
531 	struct msm_priv *priv = to_msm_priv(domain);
532 	unsigned long flags;
533 
534 	spin_lock_irqsave(&priv->pgtlock, flags);
535 	len = priv->iop->unmap(priv->iop, iova, len);
536 	spin_unlock_irqrestore(&priv->pgtlock, flags);
537 
538 	return len;
539 }
540 
541 static phys_addr_t msm_iommu_iova_to_phys(struct iommu_domain *domain,
542 					  dma_addr_t va)
543 {
544 	struct msm_priv *priv;
545 	struct msm_iommu_dev *iommu;
546 	struct msm_iommu_ctx_dev *master;
547 	unsigned int par;
548 	unsigned long flags;
549 	phys_addr_t ret = 0;
550 
551 	spin_lock_irqsave(&msm_iommu_lock, flags);
552 
553 	priv = to_msm_priv(domain);
554 	iommu = list_first_entry(&priv->list_attached,
555 				 struct msm_iommu_dev, dom_node);
556 
557 	if (list_empty(&iommu->ctx_list))
558 		goto fail;
559 
560 	master = list_first_entry(&iommu->ctx_list,
561 				  struct msm_iommu_ctx_dev, list);
562 	if (!master)
563 		goto fail;
564 
565 	ret = __enable_clocks(iommu);
566 	if (ret)
567 		goto fail;
568 
569 	/* Invalidate context TLB */
570 	SET_CTX_TLBIALL(iommu->base, master->num, 0);
571 	SET_V2PPR(iommu->base, master->num, va & V2Pxx_VA);
572 
573 	par = GET_PAR(iommu->base, master->num);
574 
575 	/* We are dealing with a supersection */
576 	if (GET_NOFAULT_SS(iommu->base, master->num))
577 		ret = (par & 0xFF000000) | (va & 0x00FFFFFF);
578 	else	/* Upper 20 bits from PAR, lower 12 from VA */
579 		ret = (par & 0xFFFFF000) | (va & 0x00000FFF);
580 
581 	if (GET_FAULT(iommu->base, master->num))
582 		ret = 0;
583 
584 	__disable_clocks(iommu);
585 fail:
586 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
587 	return ret;
588 }
589 
590 static bool msm_iommu_capable(enum iommu_cap cap)
591 {
592 	return false;
593 }
594 
595 static void print_ctx_regs(void __iomem *base, int ctx)
596 {
597 	unsigned int fsr = GET_FSR(base, ctx);
598 	pr_err("FAR    = %08x    PAR    = %08x\n",
599 	       GET_FAR(base, ctx), GET_PAR(base, ctx));
600 	pr_err("FSR    = %08x [%s%s%s%s%s%s%s%s%s%s]\n", fsr,
601 			(fsr & 0x02) ? "TF " : "",
602 			(fsr & 0x04) ? "AFF " : "",
603 			(fsr & 0x08) ? "APF " : "",
604 			(fsr & 0x10) ? "TLBMF " : "",
605 			(fsr & 0x20) ? "HTWDEEF " : "",
606 			(fsr & 0x40) ? "HTWSEEF " : "",
607 			(fsr & 0x80) ? "MHF " : "",
608 			(fsr & 0x10000) ? "SL " : "",
609 			(fsr & 0x40000000) ? "SS " : "",
610 			(fsr & 0x80000000) ? "MULTI " : "");
611 
612 	pr_err("FSYNR0 = %08x    FSYNR1 = %08x\n",
613 	       GET_FSYNR0(base, ctx), GET_FSYNR1(base, ctx));
614 	pr_err("TTBR0  = %08x    TTBR1  = %08x\n",
615 	       GET_TTBR0(base, ctx), GET_TTBR1(base, ctx));
616 	pr_err("SCTLR  = %08x    ACTLR  = %08x\n",
617 	       GET_SCTLR(base, ctx), GET_ACTLR(base, ctx));
618 }
619 
620 static void insert_iommu_master(struct device *dev,
621 				struct msm_iommu_dev **iommu,
622 				struct of_phandle_args *spec)
623 {
624 	struct msm_iommu_ctx_dev *master = dev->archdata.iommu;
625 	int sid;
626 
627 	if (list_empty(&(*iommu)->ctx_list)) {
628 		master = kzalloc(sizeof(*master), GFP_ATOMIC);
629 		master->of_node = dev->of_node;
630 		list_add(&master->list, &(*iommu)->ctx_list);
631 		dev->archdata.iommu = master;
632 	}
633 
634 	for (sid = 0; sid < master->num_mids; sid++)
635 		if (master->mids[sid] == spec->args[0]) {
636 			dev_warn(dev, "Stream ID 0x%hx repeated; ignoring\n",
637 				 sid);
638 			return;
639 		}
640 
641 	master->mids[master->num_mids++] = spec->args[0];
642 }
643 
644 static int qcom_iommu_of_xlate(struct device *dev,
645 			       struct of_phandle_args *spec)
646 {
647 	struct msm_iommu_dev *iommu;
648 	unsigned long flags;
649 	int ret = 0;
650 
651 	spin_lock_irqsave(&msm_iommu_lock, flags);
652 	list_for_each_entry(iommu, &qcom_iommu_devices, dev_node)
653 		if (iommu->dev->of_node == spec->np)
654 			break;
655 
656 	if (!iommu || iommu->dev->of_node != spec->np) {
657 		ret = -ENODEV;
658 		goto fail;
659 	}
660 
661 	insert_iommu_master(dev, &iommu, spec);
662 fail:
663 	spin_unlock_irqrestore(&msm_iommu_lock, flags);
664 
665 	return ret;
666 }
667 
668 irqreturn_t msm_iommu_fault_handler(int irq, void *dev_id)
669 {
670 	struct msm_iommu_dev *iommu = dev_id;
671 	unsigned int fsr;
672 	int i, ret;
673 
674 	spin_lock(&msm_iommu_lock);
675 
676 	if (!iommu) {
677 		pr_err("Invalid device ID in context interrupt handler\n");
678 		goto fail;
679 	}
680 
681 	pr_err("Unexpected IOMMU page fault!\n");
682 	pr_err("base = %08x\n", (unsigned int)iommu->base);
683 
684 	ret = __enable_clocks(iommu);
685 	if (ret)
686 		goto fail;
687 
688 	for (i = 0; i < iommu->ncb; i++) {
689 		fsr = GET_FSR(iommu->base, i);
690 		if (fsr) {
691 			pr_err("Fault occurred in context %d.\n", i);
692 			pr_err("Interesting registers:\n");
693 			print_ctx_regs(iommu->base, i);
694 			SET_FSR(iommu->base, i, 0x4000000F);
695 		}
696 	}
697 	__disable_clocks(iommu);
698 fail:
699 	spin_unlock(&msm_iommu_lock);
700 	return 0;
701 }
702 
703 static struct iommu_ops msm_iommu_ops = {
704 	.capable = msm_iommu_capable,
705 	.domain_alloc = msm_iommu_domain_alloc,
706 	.domain_free = msm_iommu_domain_free,
707 	.attach_dev = msm_iommu_attach_dev,
708 	.detach_dev = msm_iommu_detach_dev,
709 	.map = msm_iommu_map,
710 	.unmap = msm_iommu_unmap,
711 	.map_sg = default_iommu_map_sg,
712 	.iova_to_phys = msm_iommu_iova_to_phys,
713 	.add_device = msm_iommu_add_device,
714 	.remove_device = msm_iommu_remove_device,
715 	.device_group = generic_device_group,
716 	.pgsize_bitmap = MSM_IOMMU_PGSIZES,
717 	.of_xlate = qcom_iommu_of_xlate,
718 };
719 
720 static int msm_iommu_probe(struct platform_device *pdev)
721 {
722 	struct resource *r;
723 	resource_size_t ioaddr;
724 	struct msm_iommu_dev *iommu;
725 	int ret, par, val;
726 
727 	iommu = devm_kzalloc(&pdev->dev, sizeof(*iommu), GFP_KERNEL);
728 	if (!iommu)
729 		return -ENODEV;
730 
731 	iommu->dev = &pdev->dev;
732 	INIT_LIST_HEAD(&iommu->ctx_list);
733 
734 	iommu->pclk = devm_clk_get(iommu->dev, "smmu_pclk");
735 	if (IS_ERR(iommu->pclk)) {
736 		dev_err(iommu->dev, "could not get smmu_pclk\n");
737 		return PTR_ERR(iommu->pclk);
738 	}
739 
740 	ret = clk_prepare(iommu->pclk);
741 	if (ret) {
742 		dev_err(iommu->dev, "could not prepare smmu_pclk\n");
743 		return ret;
744 	}
745 
746 	iommu->clk = devm_clk_get(iommu->dev, "iommu_clk");
747 	if (IS_ERR(iommu->clk)) {
748 		dev_err(iommu->dev, "could not get iommu_clk\n");
749 		clk_unprepare(iommu->pclk);
750 		return PTR_ERR(iommu->clk);
751 	}
752 
753 	ret = clk_prepare(iommu->clk);
754 	if (ret) {
755 		dev_err(iommu->dev, "could not prepare iommu_clk\n");
756 		clk_unprepare(iommu->pclk);
757 		return ret;
758 	}
759 
760 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
761 	iommu->base = devm_ioremap_resource(iommu->dev, r);
762 	if (IS_ERR(iommu->base)) {
763 		dev_err(iommu->dev, "could not get iommu base\n");
764 		ret = PTR_ERR(iommu->base);
765 		goto fail;
766 	}
767 	ioaddr = r->start;
768 
769 	iommu->irq = platform_get_irq(pdev, 0);
770 	if (iommu->irq < 0) {
771 		dev_err(iommu->dev, "could not get iommu irq\n");
772 		ret = -ENODEV;
773 		goto fail;
774 	}
775 
776 	ret = of_property_read_u32(iommu->dev->of_node, "qcom,ncb", &val);
777 	if (ret) {
778 		dev_err(iommu->dev, "could not get ncb\n");
779 		goto fail;
780 	}
781 	iommu->ncb = val;
782 
783 	msm_iommu_reset(iommu->base, iommu->ncb);
784 	SET_M(iommu->base, 0, 1);
785 	SET_PAR(iommu->base, 0, 0);
786 	SET_V2PCFG(iommu->base, 0, 1);
787 	SET_V2PPR(iommu->base, 0, 0);
788 	par = GET_PAR(iommu->base, 0);
789 	SET_V2PCFG(iommu->base, 0, 0);
790 	SET_M(iommu->base, 0, 0);
791 
792 	if (!par) {
793 		pr_err("Invalid PAR value detected\n");
794 		ret = -ENODEV;
795 		goto fail;
796 	}
797 
798 	ret = devm_request_threaded_irq(iommu->dev, iommu->irq, NULL,
799 					msm_iommu_fault_handler,
800 					IRQF_ONESHOT | IRQF_SHARED,
801 					"msm_iommu_secure_irpt_handler",
802 					iommu);
803 	if (ret) {
804 		pr_err("Request IRQ %d failed with ret=%d\n", iommu->irq, ret);
805 		goto fail;
806 	}
807 
808 	list_add(&iommu->dev_node, &qcom_iommu_devices);
809 
810 	ret = iommu_device_sysfs_add(&iommu->iommu, iommu->dev, NULL,
811 				     "msm-smmu.%pa", &ioaddr);
812 	if (ret) {
813 		pr_err("Could not add msm-smmu at %pa to sysfs\n", &ioaddr);
814 		goto fail;
815 	}
816 
817 	iommu_device_set_ops(&iommu->iommu, &msm_iommu_ops);
818 	iommu_device_set_fwnode(&iommu->iommu, &pdev->dev.of_node->fwnode);
819 
820 	ret = iommu_device_register(&iommu->iommu);
821 	if (ret) {
822 		pr_err("Could not register msm-smmu at %pa\n", &ioaddr);
823 		goto fail;
824 	}
825 
826 	bus_set_iommu(&platform_bus_type, &msm_iommu_ops);
827 
828 	pr_info("device mapped at %p, irq %d with %d ctx banks\n",
829 		iommu->base, iommu->irq, iommu->ncb);
830 
831 	return ret;
832 fail:
833 	clk_unprepare(iommu->clk);
834 	clk_unprepare(iommu->pclk);
835 	return ret;
836 }
837 
838 static const struct of_device_id msm_iommu_dt_match[] = {
839 	{ .compatible = "qcom,apq8064-iommu" },
840 	{}
841 };
842 
843 static int msm_iommu_remove(struct platform_device *pdev)
844 {
845 	struct msm_iommu_dev *iommu = platform_get_drvdata(pdev);
846 
847 	clk_unprepare(iommu->clk);
848 	clk_unprepare(iommu->pclk);
849 	return 0;
850 }
851 
852 static struct platform_driver msm_iommu_driver = {
853 	.driver = {
854 		.name	= "msm_iommu",
855 		.of_match_table = msm_iommu_dt_match,
856 	},
857 	.probe		= msm_iommu_probe,
858 	.remove		= msm_iommu_remove,
859 };
860 
861 static int __init msm_iommu_driver_init(void)
862 {
863 	int ret;
864 
865 	ret = platform_driver_register(&msm_iommu_driver);
866 	if (ret != 0)
867 		pr_err("Failed to register IOMMU driver\n");
868 
869 	return ret;
870 }
871 
872 static void __exit msm_iommu_driver_exit(void)
873 {
874 	platform_driver_unregister(&msm_iommu_driver);
875 }
876 
877 subsys_initcall(msm_iommu_driver_init);
878 module_exit(msm_iommu_driver_exit);
879 
880 IOMMU_OF_DECLARE(msm_iommu_of, "qcom,apq8064-iommu");
881 
882 MODULE_LICENSE("GPL v2");
883 MODULE_AUTHOR("Stepan Moskovchenko <stepanm@codeaurora.org>");
884