xref: /linux/drivers/iommu/arm/arm-smmu/qcom_iommu.c (revision 26fbb4c8c7c3ee9a4c3b4de555a8587b5a19154e)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * IOMMU API for QCOM secure IOMMUs.  Somewhat based on arm-smmu.c
4  *
5  * Copyright (C) 2013 ARM Limited
6  * Copyright (C) 2017 Red Hat
7  */
8 
9 #include <linux/atomic.h>
10 #include <linux/bitfield.h>
11 #include <linux/clk.h>
12 #include <linux/delay.h>
13 #include <linux/dma-iommu.h>
14 #include <linux/dma-mapping.h>
15 #include <linux/err.h>
16 #include <linux/interrupt.h>
17 #include <linux/io.h>
18 #include <linux/io-64-nonatomic-hi-lo.h>
19 #include <linux/io-pgtable.h>
20 #include <linux/iommu.h>
21 #include <linux/iopoll.h>
22 #include <linux/kconfig.h>
23 #include <linux/init.h>
24 #include <linux/mutex.h>
25 #include <linux/of.h>
26 #include <linux/of_address.h>
27 #include <linux/of_device.h>
28 #include <linux/of_iommu.h>
29 #include <linux/platform_device.h>
30 #include <linux/pm.h>
31 #include <linux/pm_runtime.h>
32 #include <linux/qcom_scm.h>
33 #include <linux/slab.h>
34 #include <linux/spinlock.h>
35 
36 #include "arm-smmu.h"
37 
38 #define SMMU_INTR_SEL_NS     0x2000
39 
40 enum qcom_iommu_clk {
41 	CLK_IFACE,
42 	CLK_BUS,
43 	CLK_TBU,
44 	CLK_NUM,
45 };
46 
47 struct qcom_iommu_ctx;
48 
49 struct qcom_iommu_dev {
50 	/* IOMMU core code handle */
51 	struct iommu_device	 iommu;
52 	struct device		*dev;
53 	struct clk_bulk_data clks[CLK_NUM];
54 	void __iomem		*local_base;
55 	u32			 sec_id;
56 	u8			 num_ctxs;
57 	struct qcom_iommu_ctx	*ctxs[];   /* indexed by asid-1 */
58 };
59 
60 struct qcom_iommu_ctx {
61 	struct device		*dev;
62 	void __iomem		*base;
63 	bool			 secure_init;
64 	u8			 asid;      /* asid and ctx bank # are 1:1 */
65 	struct iommu_domain	*domain;
66 };
67 
68 struct qcom_iommu_domain {
69 	struct io_pgtable_ops	*pgtbl_ops;
70 	spinlock_t		 pgtbl_lock;
71 	struct mutex		 init_mutex; /* Protects iommu pointer */
72 	struct iommu_domain	 domain;
73 	struct qcom_iommu_dev	*iommu;
74 	struct iommu_fwspec	*fwspec;
75 };
76 
77 static struct qcom_iommu_domain *to_qcom_iommu_domain(struct iommu_domain *dom)
78 {
79 	return container_of(dom, struct qcom_iommu_domain, domain);
80 }
81 
82 static const struct iommu_ops qcom_iommu_ops;
83 
84 static struct qcom_iommu_dev * to_iommu(struct device *dev)
85 {
86 	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
87 
88 	if (!fwspec || fwspec->ops != &qcom_iommu_ops)
89 		return NULL;
90 
91 	return dev_iommu_priv_get(dev);
92 }
93 
94 static struct qcom_iommu_ctx * to_ctx(struct qcom_iommu_domain *d, unsigned asid)
95 {
96 	struct qcom_iommu_dev *qcom_iommu = d->iommu;
97 	if (!qcom_iommu)
98 		return NULL;
99 	return qcom_iommu->ctxs[asid - 1];
100 }
101 
102 static inline void
103 iommu_writel(struct qcom_iommu_ctx *ctx, unsigned reg, u32 val)
104 {
105 	writel_relaxed(val, ctx->base + reg);
106 }
107 
108 static inline void
109 iommu_writeq(struct qcom_iommu_ctx *ctx, unsigned reg, u64 val)
110 {
111 	writeq_relaxed(val, ctx->base + reg);
112 }
113 
114 static inline u32
115 iommu_readl(struct qcom_iommu_ctx *ctx, unsigned reg)
116 {
117 	return readl_relaxed(ctx->base + reg);
118 }
119 
120 static inline u64
121 iommu_readq(struct qcom_iommu_ctx *ctx, unsigned reg)
122 {
123 	return readq_relaxed(ctx->base + reg);
124 }
125 
126 static void qcom_iommu_tlb_sync(void *cookie)
127 {
128 	struct qcom_iommu_domain *qcom_domain = cookie;
129 	struct iommu_fwspec *fwspec = qcom_domain->fwspec;
130 	unsigned i;
131 
132 	for (i = 0; i < fwspec->num_ids; i++) {
133 		struct qcom_iommu_ctx *ctx = to_ctx(qcom_domain, fwspec->ids[i]);
134 		unsigned int val, ret;
135 
136 		iommu_writel(ctx, ARM_SMMU_CB_TLBSYNC, 0);
137 
138 		ret = readl_poll_timeout(ctx->base + ARM_SMMU_CB_TLBSTATUS, val,
139 					 (val & 0x1) == 0, 0, 5000000);
140 		if (ret)
141 			dev_err(ctx->dev, "timeout waiting for TLB SYNC\n");
142 	}
143 }
144 
145 static void qcom_iommu_tlb_inv_context(void *cookie)
146 {
147 	struct qcom_iommu_domain *qcom_domain = cookie;
148 	struct iommu_fwspec *fwspec = qcom_domain->fwspec;
149 	unsigned i;
150 
151 	for (i = 0; i < fwspec->num_ids; i++) {
152 		struct qcom_iommu_ctx *ctx = to_ctx(qcom_domain, fwspec->ids[i]);
153 		iommu_writel(ctx, ARM_SMMU_CB_S1_TLBIASID, ctx->asid);
154 	}
155 
156 	qcom_iommu_tlb_sync(cookie);
157 }
158 
159 static void qcom_iommu_tlb_inv_range_nosync(unsigned long iova, size_t size,
160 					    size_t granule, bool leaf, void *cookie)
161 {
162 	struct qcom_iommu_domain *qcom_domain = cookie;
163 	struct iommu_fwspec *fwspec = qcom_domain->fwspec;
164 	unsigned i, reg;
165 
166 	reg = leaf ? ARM_SMMU_CB_S1_TLBIVAL : ARM_SMMU_CB_S1_TLBIVA;
167 
168 	for (i = 0; i < fwspec->num_ids; i++) {
169 		struct qcom_iommu_ctx *ctx = to_ctx(qcom_domain, fwspec->ids[i]);
170 		size_t s = size;
171 
172 		iova = (iova >> 12) << 12;
173 		iova |= ctx->asid;
174 		do {
175 			iommu_writel(ctx, reg, iova);
176 			iova += granule;
177 		} while (s -= granule);
178 	}
179 }
180 
181 static void qcom_iommu_tlb_flush_walk(unsigned long iova, size_t size,
182 				      size_t granule, void *cookie)
183 {
184 	qcom_iommu_tlb_inv_range_nosync(iova, size, granule, false, cookie);
185 	qcom_iommu_tlb_sync(cookie);
186 }
187 
188 static void qcom_iommu_tlb_add_page(struct iommu_iotlb_gather *gather,
189 				    unsigned long iova, size_t granule,
190 				    void *cookie)
191 {
192 	qcom_iommu_tlb_inv_range_nosync(iova, granule, granule, true, cookie);
193 }
194 
195 static const struct iommu_flush_ops qcom_flush_ops = {
196 	.tlb_flush_all	= qcom_iommu_tlb_inv_context,
197 	.tlb_flush_walk = qcom_iommu_tlb_flush_walk,
198 	.tlb_add_page	= qcom_iommu_tlb_add_page,
199 };
200 
201 static irqreturn_t qcom_iommu_fault(int irq, void *dev)
202 {
203 	struct qcom_iommu_ctx *ctx = dev;
204 	u32 fsr, fsynr;
205 	u64 iova;
206 
207 	fsr = iommu_readl(ctx, ARM_SMMU_CB_FSR);
208 
209 	if (!(fsr & ARM_SMMU_FSR_FAULT))
210 		return IRQ_NONE;
211 
212 	fsynr = iommu_readl(ctx, ARM_SMMU_CB_FSYNR0);
213 	iova = iommu_readq(ctx, ARM_SMMU_CB_FAR);
214 
215 	if (!report_iommu_fault(ctx->domain, ctx->dev, iova, 0)) {
216 		dev_err_ratelimited(ctx->dev,
217 				    "Unhandled context fault: fsr=0x%x, "
218 				    "iova=0x%016llx, fsynr=0x%x, cb=%d\n",
219 				    fsr, iova, fsynr, ctx->asid);
220 	}
221 
222 	iommu_writel(ctx, ARM_SMMU_CB_FSR, fsr);
223 	iommu_writel(ctx, ARM_SMMU_CB_RESUME, ARM_SMMU_RESUME_TERMINATE);
224 
225 	return IRQ_HANDLED;
226 }
227 
228 static int qcom_iommu_init_domain(struct iommu_domain *domain,
229 				  struct qcom_iommu_dev *qcom_iommu,
230 				  struct device *dev)
231 {
232 	struct qcom_iommu_domain *qcom_domain = to_qcom_iommu_domain(domain);
233 	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
234 	struct io_pgtable_ops *pgtbl_ops;
235 	struct io_pgtable_cfg pgtbl_cfg;
236 	int i, ret = 0;
237 	u32 reg;
238 
239 	mutex_lock(&qcom_domain->init_mutex);
240 	if (qcom_domain->iommu)
241 		goto out_unlock;
242 
243 	pgtbl_cfg = (struct io_pgtable_cfg) {
244 		.pgsize_bitmap	= qcom_iommu_ops.pgsize_bitmap,
245 		.ias		= 32,
246 		.oas		= 40,
247 		.tlb		= &qcom_flush_ops,
248 		.iommu_dev	= qcom_iommu->dev,
249 	};
250 
251 	qcom_domain->iommu = qcom_iommu;
252 	qcom_domain->fwspec = fwspec;
253 
254 	pgtbl_ops = alloc_io_pgtable_ops(ARM_32_LPAE_S1, &pgtbl_cfg, qcom_domain);
255 	if (!pgtbl_ops) {
256 		dev_err(qcom_iommu->dev, "failed to allocate pagetable ops\n");
257 		ret = -ENOMEM;
258 		goto out_clear_iommu;
259 	}
260 
261 	/* Update the domain's page sizes to reflect the page table format */
262 	domain->pgsize_bitmap = pgtbl_cfg.pgsize_bitmap;
263 	domain->geometry.aperture_end = (1ULL << pgtbl_cfg.ias) - 1;
264 	domain->geometry.force_aperture = true;
265 
266 	for (i = 0; i < fwspec->num_ids; i++) {
267 		struct qcom_iommu_ctx *ctx = to_ctx(qcom_domain, fwspec->ids[i]);
268 
269 		if (!ctx->secure_init) {
270 			ret = qcom_scm_restore_sec_cfg(qcom_iommu->sec_id, ctx->asid);
271 			if (ret) {
272 				dev_err(qcom_iommu->dev, "secure init failed: %d\n", ret);
273 				goto out_clear_iommu;
274 			}
275 			ctx->secure_init = true;
276 		}
277 
278 		/* TTBRs */
279 		iommu_writeq(ctx, ARM_SMMU_CB_TTBR0,
280 				pgtbl_cfg.arm_lpae_s1_cfg.ttbr |
281 				FIELD_PREP(ARM_SMMU_TTBRn_ASID, ctx->asid));
282 		iommu_writeq(ctx, ARM_SMMU_CB_TTBR1, 0);
283 
284 		/* TCR */
285 		iommu_writel(ctx, ARM_SMMU_CB_TCR2,
286 				arm_smmu_lpae_tcr2(&pgtbl_cfg));
287 		iommu_writel(ctx, ARM_SMMU_CB_TCR,
288 			     arm_smmu_lpae_tcr(&pgtbl_cfg) | ARM_SMMU_TCR_EAE);
289 
290 		/* MAIRs (stage-1 only) */
291 		iommu_writel(ctx, ARM_SMMU_CB_S1_MAIR0,
292 				pgtbl_cfg.arm_lpae_s1_cfg.mair);
293 		iommu_writel(ctx, ARM_SMMU_CB_S1_MAIR1,
294 				pgtbl_cfg.arm_lpae_s1_cfg.mair >> 32);
295 
296 		/* SCTLR */
297 		reg = ARM_SMMU_SCTLR_CFIE | ARM_SMMU_SCTLR_CFRE |
298 		      ARM_SMMU_SCTLR_AFE | ARM_SMMU_SCTLR_TRE |
299 		      ARM_SMMU_SCTLR_M | ARM_SMMU_SCTLR_S1_ASIDPNE |
300 		      ARM_SMMU_SCTLR_CFCFG;
301 
302 		if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
303 			reg |= ARM_SMMU_SCTLR_E;
304 
305 		iommu_writel(ctx, ARM_SMMU_CB_SCTLR, reg);
306 
307 		ctx->domain = domain;
308 	}
309 
310 	mutex_unlock(&qcom_domain->init_mutex);
311 
312 	/* Publish page table ops for map/unmap */
313 	qcom_domain->pgtbl_ops = pgtbl_ops;
314 
315 	return 0;
316 
317 out_clear_iommu:
318 	qcom_domain->iommu = NULL;
319 out_unlock:
320 	mutex_unlock(&qcom_domain->init_mutex);
321 	return ret;
322 }
323 
324 static struct iommu_domain *qcom_iommu_domain_alloc(unsigned type)
325 {
326 	struct qcom_iommu_domain *qcom_domain;
327 
328 	if (type != IOMMU_DOMAIN_UNMANAGED && type != IOMMU_DOMAIN_DMA)
329 		return NULL;
330 	/*
331 	 * Allocate the domain and initialise some of its data structures.
332 	 * We can't really do anything meaningful until we've added a
333 	 * master.
334 	 */
335 	qcom_domain = kzalloc(sizeof(*qcom_domain), GFP_KERNEL);
336 	if (!qcom_domain)
337 		return NULL;
338 
339 	if (type == IOMMU_DOMAIN_DMA &&
340 	    iommu_get_dma_cookie(&qcom_domain->domain)) {
341 		kfree(qcom_domain);
342 		return NULL;
343 	}
344 
345 	mutex_init(&qcom_domain->init_mutex);
346 	spin_lock_init(&qcom_domain->pgtbl_lock);
347 
348 	return &qcom_domain->domain;
349 }
350 
351 static void qcom_iommu_domain_free(struct iommu_domain *domain)
352 {
353 	struct qcom_iommu_domain *qcom_domain = to_qcom_iommu_domain(domain);
354 
355 	iommu_put_dma_cookie(domain);
356 
357 	if (qcom_domain->iommu) {
358 		/*
359 		 * NOTE: unmap can be called after client device is powered
360 		 * off, for example, with GPUs or anything involving dma-buf.
361 		 * So we cannot rely on the device_link.  Make sure the IOMMU
362 		 * is on to avoid unclocked accesses in the TLB inv path:
363 		 */
364 		pm_runtime_get_sync(qcom_domain->iommu->dev);
365 		free_io_pgtable_ops(qcom_domain->pgtbl_ops);
366 		pm_runtime_put_sync(qcom_domain->iommu->dev);
367 	}
368 
369 	kfree(qcom_domain);
370 }
371 
372 static int qcom_iommu_attach_dev(struct iommu_domain *domain, struct device *dev)
373 {
374 	struct qcom_iommu_dev *qcom_iommu = to_iommu(dev);
375 	struct qcom_iommu_domain *qcom_domain = to_qcom_iommu_domain(domain);
376 	int ret;
377 
378 	if (!qcom_iommu) {
379 		dev_err(dev, "cannot attach to IOMMU, is it on the same bus?\n");
380 		return -ENXIO;
381 	}
382 
383 	/* Ensure that the domain is finalized */
384 	pm_runtime_get_sync(qcom_iommu->dev);
385 	ret = qcom_iommu_init_domain(domain, qcom_iommu, dev);
386 	pm_runtime_put_sync(qcom_iommu->dev);
387 	if (ret < 0)
388 		return ret;
389 
390 	/*
391 	 * Sanity check the domain. We don't support domains across
392 	 * different IOMMUs.
393 	 */
394 	if (qcom_domain->iommu != qcom_iommu) {
395 		dev_err(dev, "cannot attach to IOMMU %s while already "
396 			"attached to domain on IOMMU %s\n",
397 			dev_name(qcom_domain->iommu->dev),
398 			dev_name(qcom_iommu->dev));
399 		return -EINVAL;
400 	}
401 
402 	return 0;
403 }
404 
405 static void qcom_iommu_detach_dev(struct iommu_domain *domain, struct device *dev)
406 {
407 	struct qcom_iommu_domain *qcom_domain = to_qcom_iommu_domain(domain);
408 	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
409 	struct qcom_iommu_dev *qcom_iommu = to_iommu(dev);
410 	unsigned i;
411 
412 	if (WARN_ON(!qcom_domain->iommu))
413 		return;
414 
415 	pm_runtime_get_sync(qcom_iommu->dev);
416 	for (i = 0; i < fwspec->num_ids; i++) {
417 		struct qcom_iommu_ctx *ctx = to_ctx(qcom_domain, fwspec->ids[i]);
418 
419 		/* Disable the context bank: */
420 		iommu_writel(ctx, ARM_SMMU_CB_SCTLR, 0);
421 
422 		ctx->domain = NULL;
423 	}
424 	pm_runtime_put_sync(qcom_iommu->dev);
425 }
426 
427 static int qcom_iommu_map(struct iommu_domain *domain, unsigned long iova,
428 			  phys_addr_t paddr, size_t size, int prot, gfp_t gfp)
429 {
430 	int ret;
431 	unsigned long flags;
432 	struct qcom_iommu_domain *qcom_domain = to_qcom_iommu_domain(domain);
433 	struct io_pgtable_ops *ops = qcom_domain->pgtbl_ops;
434 
435 	if (!ops)
436 		return -ENODEV;
437 
438 	spin_lock_irqsave(&qcom_domain->pgtbl_lock, flags);
439 	ret = ops->map(ops, iova, paddr, size, prot, GFP_ATOMIC);
440 	spin_unlock_irqrestore(&qcom_domain->pgtbl_lock, flags);
441 	return ret;
442 }
443 
444 static size_t qcom_iommu_unmap(struct iommu_domain *domain, unsigned long iova,
445 			       size_t size, struct iommu_iotlb_gather *gather)
446 {
447 	size_t ret;
448 	unsigned long flags;
449 	struct qcom_iommu_domain *qcom_domain = to_qcom_iommu_domain(domain);
450 	struct io_pgtable_ops *ops = qcom_domain->pgtbl_ops;
451 
452 	if (!ops)
453 		return 0;
454 
455 	/* NOTE: unmap can be called after client device is powered off,
456 	 * for example, with GPUs or anything involving dma-buf.  So we
457 	 * cannot rely on the device_link.  Make sure the IOMMU is on to
458 	 * avoid unclocked accesses in the TLB inv path:
459 	 */
460 	pm_runtime_get_sync(qcom_domain->iommu->dev);
461 	spin_lock_irqsave(&qcom_domain->pgtbl_lock, flags);
462 	ret = ops->unmap(ops, iova, size, gather);
463 	spin_unlock_irqrestore(&qcom_domain->pgtbl_lock, flags);
464 	pm_runtime_put_sync(qcom_domain->iommu->dev);
465 
466 	return ret;
467 }
468 
469 static void qcom_iommu_flush_iotlb_all(struct iommu_domain *domain)
470 {
471 	struct qcom_iommu_domain *qcom_domain = to_qcom_iommu_domain(domain);
472 	struct io_pgtable *pgtable = container_of(qcom_domain->pgtbl_ops,
473 						  struct io_pgtable, ops);
474 	if (!qcom_domain->pgtbl_ops)
475 		return;
476 
477 	pm_runtime_get_sync(qcom_domain->iommu->dev);
478 	qcom_iommu_tlb_sync(pgtable->cookie);
479 	pm_runtime_put_sync(qcom_domain->iommu->dev);
480 }
481 
482 static void qcom_iommu_iotlb_sync(struct iommu_domain *domain,
483 				  struct iommu_iotlb_gather *gather)
484 {
485 	qcom_iommu_flush_iotlb_all(domain);
486 }
487 
488 static phys_addr_t qcom_iommu_iova_to_phys(struct iommu_domain *domain,
489 					   dma_addr_t iova)
490 {
491 	phys_addr_t ret;
492 	unsigned long flags;
493 	struct qcom_iommu_domain *qcom_domain = to_qcom_iommu_domain(domain);
494 	struct io_pgtable_ops *ops = qcom_domain->pgtbl_ops;
495 
496 	if (!ops)
497 		return 0;
498 
499 	spin_lock_irqsave(&qcom_domain->pgtbl_lock, flags);
500 	ret = ops->iova_to_phys(ops, iova);
501 	spin_unlock_irqrestore(&qcom_domain->pgtbl_lock, flags);
502 
503 	return ret;
504 }
505 
506 static bool qcom_iommu_capable(enum iommu_cap cap)
507 {
508 	switch (cap) {
509 	case IOMMU_CAP_CACHE_COHERENCY:
510 		/*
511 		 * Return true here as the SMMU can always send out coherent
512 		 * requests.
513 		 */
514 		return true;
515 	case IOMMU_CAP_NOEXEC:
516 		return true;
517 	default:
518 		return false;
519 	}
520 }
521 
522 static struct iommu_device *qcom_iommu_probe_device(struct device *dev)
523 {
524 	struct qcom_iommu_dev *qcom_iommu = to_iommu(dev);
525 	struct device_link *link;
526 
527 	if (!qcom_iommu)
528 		return ERR_PTR(-ENODEV);
529 
530 	/*
531 	 * Establish the link between iommu and master, so that the
532 	 * iommu gets runtime enabled/disabled as per the master's
533 	 * needs.
534 	 */
535 	link = device_link_add(dev, qcom_iommu->dev, DL_FLAG_PM_RUNTIME);
536 	if (!link) {
537 		dev_err(qcom_iommu->dev, "Unable to create device link between %s and %s\n",
538 			dev_name(qcom_iommu->dev), dev_name(dev));
539 		return ERR_PTR(-ENODEV);
540 	}
541 
542 	return &qcom_iommu->iommu;
543 }
544 
545 static void qcom_iommu_release_device(struct device *dev)
546 {
547 	struct qcom_iommu_dev *qcom_iommu = to_iommu(dev);
548 
549 	if (!qcom_iommu)
550 		return;
551 
552 	iommu_fwspec_free(dev);
553 }
554 
555 static int qcom_iommu_of_xlate(struct device *dev, struct of_phandle_args *args)
556 {
557 	struct qcom_iommu_dev *qcom_iommu;
558 	struct platform_device *iommu_pdev;
559 	unsigned asid = args->args[0];
560 
561 	if (args->args_count != 1) {
562 		dev_err(dev, "incorrect number of iommu params found for %s "
563 			"(found %d, expected 1)\n",
564 			args->np->full_name, args->args_count);
565 		return -EINVAL;
566 	}
567 
568 	iommu_pdev = of_find_device_by_node(args->np);
569 	if (WARN_ON(!iommu_pdev))
570 		return -EINVAL;
571 
572 	qcom_iommu = platform_get_drvdata(iommu_pdev);
573 
574 	/* make sure the asid specified in dt is valid, so we don't have
575 	 * to sanity check this elsewhere, since 'asid - 1' is used to
576 	 * index into qcom_iommu->ctxs:
577 	 */
578 	if (WARN_ON(asid < 1) ||
579 	    WARN_ON(asid > qcom_iommu->num_ctxs)) {
580 		put_device(&iommu_pdev->dev);
581 		return -EINVAL;
582 	}
583 
584 	if (!dev_iommu_priv_get(dev)) {
585 		dev_iommu_priv_set(dev, qcom_iommu);
586 	} else {
587 		/* make sure devices iommus dt node isn't referring to
588 		 * multiple different iommu devices.  Multiple context
589 		 * banks are ok, but multiple devices are not:
590 		 */
591 		if (WARN_ON(qcom_iommu != dev_iommu_priv_get(dev))) {
592 			put_device(&iommu_pdev->dev);
593 			return -EINVAL;
594 		}
595 	}
596 
597 	return iommu_fwspec_add_ids(dev, &asid, 1);
598 }
599 
600 static const struct iommu_ops qcom_iommu_ops = {
601 	.capable	= qcom_iommu_capable,
602 	.domain_alloc	= qcom_iommu_domain_alloc,
603 	.domain_free	= qcom_iommu_domain_free,
604 	.attach_dev	= qcom_iommu_attach_dev,
605 	.detach_dev	= qcom_iommu_detach_dev,
606 	.map		= qcom_iommu_map,
607 	.unmap		= qcom_iommu_unmap,
608 	.flush_iotlb_all = qcom_iommu_flush_iotlb_all,
609 	.iotlb_sync	= qcom_iommu_iotlb_sync,
610 	.iova_to_phys	= qcom_iommu_iova_to_phys,
611 	.probe_device	= qcom_iommu_probe_device,
612 	.release_device	= qcom_iommu_release_device,
613 	.device_group	= generic_device_group,
614 	.of_xlate	= qcom_iommu_of_xlate,
615 	.pgsize_bitmap	= SZ_4K | SZ_64K | SZ_1M | SZ_16M,
616 };
617 
618 static int qcom_iommu_sec_ptbl_init(struct device *dev)
619 {
620 	size_t psize = 0;
621 	unsigned int spare = 0;
622 	void *cpu_addr;
623 	dma_addr_t paddr;
624 	unsigned long attrs;
625 	static bool allocated = false;
626 	int ret;
627 
628 	if (allocated)
629 		return 0;
630 
631 	ret = qcom_scm_iommu_secure_ptbl_size(spare, &psize);
632 	if (ret) {
633 		dev_err(dev, "failed to get iommu secure pgtable size (%d)\n",
634 			ret);
635 		return ret;
636 	}
637 
638 	dev_info(dev, "iommu sec: pgtable size: %zu\n", psize);
639 
640 	attrs = DMA_ATTR_NO_KERNEL_MAPPING;
641 
642 	cpu_addr = dma_alloc_attrs(dev, psize, &paddr, GFP_KERNEL, attrs);
643 	if (!cpu_addr) {
644 		dev_err(dev, "failed to allocate %zu bytes for pgtable\n",
645 			psize);
646 		return -ENOMEM;
647 	}
648 
649 	ret = qcom_scm_iommu_secure_ptbl_init(paddr, psize, spare);
650 	if (ret) {
651 		dev_err(dev, "failed to init iommu pgtable (%d)\n", ret);
652 		goto free_mem;
653 	}
654 
655 	allocated = true;
656 	return 0;
657 
658 free_mem:
659 	dma_free_attrs(dev, psize, cpu_addr, paddr, attrs);
660 	return ret;
661 }
662 
663 static int get_asid(const struct device_node *np)
664 {
665 	u32 reg;
666 
667 	/* read the "reg" property directly to get the relative address
668 	 * of the context bank, and calculate the asid from that:
669 	 */
670 	if (of_property_read_u32_index(np, "reg", 0, &reg))
671 		return -ENODEV;
672 
673 	return reg / 0x1000;      /* context banks are 0x1000 apart */
674 }
675 
676 static int qcom_iommu_ctx_probe(struct platform_device *pdev)
677 {
678 	struct qcom_iommu_ctx *ctx;
679 	struct device *dev = &pdev->dev;
680 	struct qcom_iommu_dev *qcom_iommu = dev_get_drvdata(dev->parent);
681 	struct resource *res;
682 	int ret, irq;
683 
684 	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
685 	if (!ctx)
686 		return -ENOMEM;
687 
688 	ctx->dev = dev;
689 	platform_set_drvdata(pdev, ctx);
690 
691 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
692 	ctx->base = devm_ioremap_resource(dev, res);
693 	if (IS_ERR(ctx->base))
694 		return PTR_ERR(ctx->base);
695 
696 	irq = platform_get_irq(pdev, 0);
697 	if (irq < 0)
698 		return -ENODEV;
699 
700 	/* clear IRQs before registering fault handler, just in case the
701 	 * boot-loader left us a surprise:
702 	 */
703 	iommu_writel(ctx, ARM_SMMU_CB_FSR, iommu_readl(ctx, ARM_SMMU_CB_FSR));
704 
705 	ret = devm_request_irq(dev, irq,
706 			       qcom_iommu_fault,
707 			       IRQF_SHARED,
708 			       "qcom-iommu-fault",
709 			       ctx);
710 	if (ret) {
711 		dev_err(dev, "failed to request IRQ %u\n", irq);
712 		return ret;
713 	}
714 
715 	ret = get_asid(dev->of_node);
716 	if (ret < 0) {
717 		dev_err(dev, "missing reg property\n");
718 		return ret;
719 	}
720 
721 	ctx->asid = ret;
722 
723 	dev_dbg(dev, "found asid %u\n", ctx->asid);
724 
725 	qcom_iommu->ctxs[ctx->asid - 1] = ctx;
726 
727 	return 0;
728 }
729 
730 static int qcom_iommu_ctx_remove(struct platform_device *pdev)
731 {
732 	struct qcom_iommu_dev *qcom_iommu = dev_get_drvdata(pdev->dev.parent);
733 	struct qcom_iommu_ctx *ctx = platform_get_drvdata(pdev);
734 
735 	platform_set_drvdata(pdev, NULL);
736 
737 	qcom_iommu->ctxs[ctx->asid - 1] = NULL;
738 
739 	return 0;
740 }
741 
742 static const struct of_device_id ctx_of_match[] = {
743 	{ .compatible = "qcom,msm-iommu-v1-ns" },
744 	{ .compatible = "qcom,msm-iommu-v1-sec" },
745 	{ /* sentinel */ }
746 };
747 
748 static struct platform_driver qcom_iommu_ctx_driver = {
749 	.driver	= {
750 		.name		= "qcom-iommu-ctx",
751 		.of_match_table	= ctx_of_match,
752 	},
753 	.probe	= qcom_iommu_ctx_probe,
754 	.remove = qcom_iommu_ctx_remove,
755 };
756 
757 static bool qcom_iommu_has_secure_context(struct qcom_iommu_dev *qcom_iommu)
758 {
759 	struct device_node *child;
760 
761 	for_each_child_of_node(qcom_iommu->dev->of_node, child)
762 		if (of_device_is_compatible(child, "qcom,msm-iommu-v1-sec"))
763 			return true;
764 
765 	return false;
766 }
767 
768 static int qcom_iommu_device_probe(struct platform_device *pdev)
769 {
770 	struct device_node *child;
771 	struct qcom_iommu_dev *qcom_iommu;
772 	struct device *dev = &pdev->dev;
773 	struct resource *res;
774 	struct clk *clk;
775 	int ret, max_asid = 0;
776 
777 	/* find the max asid (which is 1:1 to ctx bank idx), so we know how
778 	 * many child ctx devices we have:
779 	 */
780 	for_each_child_of_node(dev->of_node, child)
781 		max_asid = max(max_asid, get_asid(child));
782 
783 	qcom_iommu = devm_kzalloc(dev, struct_size(qcom_iommu, ctxs, max_asid),
784 				  GFP_KERNEL);
785 	if (!qcom_iommu)
786 		return -ENOMEM;
787 	qcom_iommu->num_ctxs = max_asid;
788 	qcom_iommu->dev = dev;
789 
790 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
791 	if (res) {
792 		qcom_iommu->local_base = devm_ioremap_resource(dev, res);
793 		if (IS_ERR(qcom_iommu->local_base))
794 			return PTR_ERR(qcom_iommu->local_base);
795 	}
796 
797 	clk = devm_clk_get(dev, "iface");
798 	if (IS_ERR(clk)) {
799 		dev_err(dev, "failed to get iface clock\n");
800 		return PTR_ERR(clk);
801 	}
802 	qcom_iommu->clks[CLK_IFACE].clk = clk;
803 
804 	clk = devm_clk_get(dev, "bus");
805 	if (IS_ERR(clk)) {
806 		dev_err(dev, "failed to get bus clock\n");
807 		return PTR_ERR(clk);
808 	}
809 	qcom_iommu->clks[CLK_BUS].clk = clk;
810 
811 	clk = devm_clk_get_optional(dev, "tbu");
812 	if (IS_ERR(clk)) {
813 		dev_err(dev, "failed to get tbu clock\n");
814 		return PTR_ERR(clk);
815 	}
816 	qcom_iommu->clks[CLK_TBU].clk = clk;
817 
818 	if (of_property_read_u32(dev->of_node, "qcom,iommu-secure-id",
819 				 &qcom_iommu->sec_id)) {
820 		dev_err(dev, "missing qcom,iommu-secure-id property\n");
821 		return -ENODEV;
822 	}
823 
824 	if (qcom_iommu_has_secure_context(qcom_iommu)) {
825 		ret = qcom_iommu_sec_ptbl_init(dev);
826 		if (ret) {
827 			dev_err(dev, "cannot init secure pg table(%d)\n", ret);
828 			return ret;
829 		}
830 	}
831 
832 	platform_set_drvdata(pdev, qcom_iommu);
833 
834 	pm_runtime_enable(dev);
835 
836 	/* register context bank devices, which are child nodes: */
837 	ret = devm_of_platform_populate(dev);
838 	if (ret) {
839 		dev_err(dev, "Failed to populate iommu contexts\n");
840 		return ret;
841 	}
842 
843 	ret = iommu_device_sysfs_add(&qcom_iommu->iommu, dev, NULL,
844 				     dev_name(dev));
845 	if (ret) {
846 		dev_err(dev, "Failed to register iommu in sysfs\n");
847 		return ret;
848 	}
849 
850 	iommu_device_set_ops(&qcom_iommu->iommu, &qcom_iommu_ops);
851 	iommu_device_set_fwnode(&qcom_iommu->iommu, dev->fwnode);
852 
853 	ret = iommu_device_register(&qcom_iommu->iommu);
854 	if (ret) {
855 		dev_err(dev, "Failed to register iommu\n");
856 		return ret;
857 	}
858 
859 	bus_set_iommu(&platform_bus_type, &qcom_iommu_ops);
860 
861 	if (qcom_iommu->local_base) {
862 		pm_runtime_get_sync(dev);
863 		writel_relaxed(0xffffffff, qcom_iommu->local_base + SMMU_INTR_SEL_NS);
864 		pm_runtime_put_sync(dev);
865 	}
866 
867 	return 0;
868 }
869 
870 static int qcom_iommu_device_remove(struct platform_device *pdev)
871 {
872 	struct qcom_iommu_dev *qcom_iommu = platform_get_drvdata(pdev);
873 
874 	bus_set_iommu(&platform_bus_type, NULL);
875 
876 	pm_runtime_force_suspend(&pdev->dev);
877 	platform_set_drvdata(pdev, NULL);
878 	iommu_device_sysfs_remove(&qcom_iommu->iommu);
879 	iommu_device_unregister(&qcom_iommu->iommu);
880 
881 	return 0;
882 }
883 
884 static int __maybe_unused qcom_iommu_resume(struct device *dev)
885 {
886 	struct qcom_iommu_dev *qcom_iommu = dev_get_drvdata(dev);
887 
888 	return clk_bulk_prepare_enable(CLK_NUM, qcom_iommu->clks);
889 }
890 
891 static int __maybe_unused qcom_iommu_suspend(struct device *dev)
892 {
893 	struct qcom_iommu_dev *qcom_iommu = dev_get_drvdata(dev);
894 
895 	clk_bulk_disable_unprepare(CLK_NUM, qcom_iommu->clks);
896 
897 	return 0;
898 }
899 
900 static const struct dev_pm_ops qcom_iommu_pm_ops = {
901 	SET_RUNTIME_PM_OPS(qcom_iommu_suspend, qcom_iommu_resume, NULL)
902 	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
903 				pm_runtime_force_resume)
904 };
905 
906 static const struct of_device_id qcom_iommu_of_match[] = {
907 	{ .compatible = "qcom,msm-iommu-v1" },
908 	{ /* sentinel */ }
909 };
910 
911 static struct platform_driver qcom_iommu_driver = {
912 	.driver	= {
913 		.name		= "qcom-iommu",
914 		.of_match_table	= qcom_iommu_of_match,
915 		.pm		= &qcom_iommu_pm_ops,
916 	},
917 	.probe	= qcom_iommu_device_probe,
918 	.remove	= qcom_iommu_device_remove,
919 };
920 
921 static int __init qcom_iommu_init(void)
922 {
923 	int ret;
924 
925 	ret = platform_driver_register(&qcom_iommu_ctx_driver);
926 	if (ret)
927 		return ret;
928 
929 	ret = platform_driver_register(&qcom_iommu_driver);
930 	if (ret)
931 		platform_driver_unregister(&qcom_iommu_ctx_driver);
932 
933 	return ret;
934 }
935 device_initcall(qcom_iommu_init);
936