xref: /linux/drivers/iommu/arm/arm-smmu/qcom_iommu.c (revision 53564f400572b1b8d9ee5bafb9c226eb1d38600a)
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-mapping.h>
14 #include <linux/err.h>
15 #include <linux/interrupt.h>
16 #include <linux/io.h>
17 #include <linux/io-64-nonatomic-hi-lo.h>
18 #include <linux/io-pgtable.h>
19 #include <linux/iommu.h>
20 #include <linux/iopoll.h>
21 #include <linux/kconfig.h>
22 #include <linux/init.h>
23 #include <linux/mutex.h>
24 #include <linux/of.h>
25 #include <linux/of_platform.h>
26 #include <linux/platform_device.h>
27 #include <linux/pm.h>
28 #include <linux/pm_runtime.h>
29 #include <linux/firmware/qcom/qcom_scm.h>
30 #include <linux/slab.h>
31 #include <linux/spinlock.h>
32 
33 #include "arm-smmu.h"
34 
35 #define SMMU_INTR_SEL_NS     0x2000
36 
37 enum qcom_iommu_clk {
38 	CLK_IFACE,
39 	CLK_BUS,
40 	CLK_TBU,
41 	CLK_NUM,
42 };
43 
44 struct qcom_iommu_ctx;
45 
46 struct qcom_iommu_dev {
47 	/* IOMMU core code handle */
48 	struct iommu_device	 iommu;
49 	struct device		*dev;
50 	struct clk_bulk_data clks[CLK_NUM];
51 	void __iomem		*local_base;
52 	u32			 sec_id;
53 	u8			 max_asid;
54 	struct qcom_iommu_ctx	*ctxs[];   /* indexed by asid */
55 };
56 
57 struct qcom_iommu_ctx {
58 	struct device		*dev;
59 	void __iomem		*base;
60 	bool			 secure_init;
61 	bool			 secured_ctx;
62 	u8			 asid;      /* asid and ctx bank # are 1:1 */
63 	struct iommu_domain	*domain;
64 };
65 
66 struct qcom_iommu_domain {
67 	struct io_pgtable_ops	*pgtbl_ops;
68 	spinlock_t		 pgtbl_lock;
69 	struct mutex		 init_mutex; /* Protects iommu pointer */
70 	struct iommu_domain	 domain;
71 	struct qcom_iommu_dev	*iommu;
72 	struct iommu_fwspec	*fwspec;
73 };
74 
to_qcom_iommu_domain(struct iommu_domain * dom)75 static struct qcom_iommu_domain *to_qcom_iommu_domain(struct iommu_domain *dom)
76 {
77 	return container_of(dom, struct qcom_iommu_domain, domain);
78 }
79 
80 static const struct iommu_ops qcom_iommu_ops;
81 
to_ctx(struct qcom_iommu_domain * d,unsigned asid)82 static struct qcom_iommu_ctx * to_ctx(struct qcom_iommu_domain *d, unsigned asid)
83 {
84 	struct qcom_iommu_dev *qcom_iommu = d->iommu;
85 	if (!qcom_iommu)
86 		return NULL;
87 	return qcom_iommu->ctxs[asid];
88 }
89 
90 static inline void
iommu_writel(struct qcom_iommu_ctx * ctx,unsigned reg,u32 val)91 iommu_writel(struct qcom_iommu_ctx *ctx, unsigned reg, u32 val)
92 {
93 	writel_relaxed(val, ctx->base + reg);
94 }
95 
96 static inline void
iommu_writeq(struct qcom_iommu_ctx * ctx,unsigned reg,u64 val)97 iommu_writeq(struct qcom_iommu_ctx *ctx, unsigned reg, u64 val)
98 {
99 	writeq_relaxed(val, ctx->base + reg);
100 }
101 
102 static inline u32
iommu_readl(struct qcom_iommu_ctx * ctx,unsigned reg)103 iommu_readl(struct qcom_iommu_ctx *ctx, unsigned reg)
104 {
105 	return readl_relaxed(ctx->base + reg);
106 }
107 
108 static inline u64
iommu_readq(struct qcom_iommu_ctx * ctx,unsigned reg)109 iommu_readq(struct qcom_iommu_ctx *ctx, unsigned reg)
110 {
111 	return readq_relaxed(ctx->base + reg);
112 }
113 
qcom_iommu_tlb_sync(void * cookie)114 static void qcom_iommu_tlb_sync(void *cookie)
115 {
116 	struct qcom_iommu_domain *qcom_domain = cookie;
117 	struct iommu_fwspec *fwspec = qcom_domain->fwspec;
118 	unsigned i;
119 
120 	for (i = 0; i < fwspec->num_ids; i++) {
121 		struct qcom_iommu_ctx *ctx = to_ctx(qcom_domain, fwspec->ids[i]);
122 		unsigned int val, ret;
123 
124 		iommu_writel(ctx, ARM_SMMU_CB_TLBSYNC, 0);
125 
126 		ret = readl_poll_timeout(ctx->base + ARM_SMMU_CB_TLBSTATUS, val,
127 					 (val & 0x1) == 0, 0, 5000000);
128 		if (ret)
129 			dev_err(ctx->dev, "timeout waiting for TLB SYNC\n");
130 	}
131 }
132 
qcom_iommu_tlb_inv_context(void * cookie)133 static void qcom_iommu_tlb_inv_context(void *cookie)
134 {
135 	struct qcom_iommu_domain *qcom_domain = cookie;
136 	struct iommu_fwspec *fwspec = qcom_domain->fwspec;
137 	unsigned i;
138 
139 	for (i = 0; i < fwspec->num_ids; i++) {
140 		struct qcom_iommu_ctx *ctx = to_ctx(qcom_domain, fwspec->ids[i]);
141 		iommu_writel(ctx, ARM_SMMU_CB_S1_TLBIASID, ctx->asid);
142 	}
143 
144 	qcom_iommu_tlb_sync(cookie);
145 }
146 
qcom_iommu_tlb_inv_range_nosync(unsigned long iova,size_t size,size_t granule,bool leaf,void * cookie)147 static void qcom_iommu_tlb_inv_range_nosync(unsigned long iova, size_t size,
148 					    size_t granule, bool leaf, void *cookie)
149 {
150 	struct qcom_iommu_domain *qcom_domain = cookie;
151 	struct iommu_fwspec *fwspec = qcom_domain->fwspec;
152 	unsigned i, reg;
153 
154 	reg = leaf ? ARM_SMMU_CB_S1_TLBIVAL : ARM_SMMU_CB_S1_TLBIVA;
155 
156 	for (i = 0; i < fwspec->num_ids; i++) {
157 		struct qcom_iommu_ctx *ctx = to_ctx(qcom_domain, fwspec->ids[i]);
158 		size_t s = size;
159 
160 		iova = (iova >> 12) << 12;
161 		iova |= ctx->asid;
162 		do {
163 			iommu_writel(ctx, reg, iova);
164 			iova += granule;
165 		} while (s -= granule);
166 	}
167 }
168 
qcom_iommu_tlb_flush_walk(unsigned long iova,size_t size,size_t granule,void * cookie)169 static void qcom_iommu_tlb_flush_walk(unsigned long iova, size_t size,
170 				      size_t granule, void *cookie)
171 {
172 	qcom_iommu_tlb_inv_range_nosync(iova, size, granule, false, cookie);
173 	qcom_iommu_tlb_sync(cookie);
174 }
175 
qcom_iommu_tlb_add_page(struct iommu_iotlb_gather * gather,unsigned long iova,size_t granule,void * cookie)176 static void qcom_iommu_tlb_add_page(struct iommu_iotlb_gather *gather,
177 				    unsigned long iova, size_t granule,
178 				    void *cookie)
179 {
180 	qcom_iommu_tlb_inv_range_nosync(iova, granule, granule, true, cookie);
181 }
182 
183 static const struct iommu_flush_ops qcom_flush_ops = {
184 	.tlb_flush_all	= qcom_iommu_tlb_inv_context,
185 	.tlb_flush_walk = qcom_iommu_tlb_flush_walk,
186 	.tlb_add_page	= qcom_iommu_tlb_add_page,
187 };
188 
qcom_iommu_fault(int irq,void * dev)189 static irqreturn_t qcom_iommu_fault(int irq, void *dev)
190 {
191 	struct qcom_iommu_ctx *ctx = dev;
192 	u32 fsr, fsynr;
193 	u64 iova;
194 
195 	fsr = iommu_readl(ctx, ARM_SMMU_CB_FSR);
196 
197 	if (!(fsr & ARM_SMMU_CB_FSR_FAULT))
198 		return IRQ_NONE;
199 
200 	fsynr = iommu_readl(ctx, ARM_SMMU_CB_FSYNR0);
201 	iova = iommu_readq(ctx, ARM_SMMU_CB_FAR);
202 
203 	if (!report_iommu_fault(ctx->domain, ctx->dev, iova, 0)) {
204 		dev_err_ratelimited(ctx->dev,
205 				    "Unhandled context fault: fsr=0x%x, "
206 				    "iova=0x%016llx, fsynr=0x%x, cb=%d\n",
207 				    fsr, iova, fsynr, ctx->asid);
208 	}
209 
210 	iommu_writel(ctx, ARM_SMMU_CB_FSR, fsr);
211 	iommu_writel(ctx, ARM_SMMU_CB_RESUME, ARM_SMMU_RESUME_TERMINATE);
212 
213 	return IRQ_HANDLED;
214 }
215 
qcom_iommu_init_domain(struct iommu_domain * domain,struct qcom_iommu_dev * qcom_iommu,struct device * dev)216 static int qcom_iommu_init_domain(struct iommu_domain *domain,
217 				  struct qcom_iommu_dev *qcom_iommu,
218 				  struct device *dev)
219 {
220 	struct qcom_iommu_domain *qcom_domain = to_qcom_iommu_domain(domain);
221 	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
222 	struct io_pgtable_ops *pgtbl_ops;
223 	struct io_pgtable_cfg pgtbl_cfg;
224 	int i, ret = 0;
225 	u32 reg;
226 
227 	mutex_lock(&qcom_domain->init_mutex);
228 	if (qcom_domain->iommu)
229 		goto out_unlock;
230 
231 	pgtbl_cfg = (struct io_pgtable_cfg) {
232 		.pgsize_bitmap	= domain->pgsize_bitmap,
233 		.ias		= 32,
234 		.oas		= 40,
235 		.tlb		= &qcom_flush_ops,
236 		.iommu_dev	= qcom_iommu->dev,
237 	};
238 
239 	qcom_domain->iommu = qcom_iommu;
240 	qcom_domain->fwspec = fwspec;
241 
242 	pgtbl_ops = alloc_io_pgtable_ops(ARM_32_LPAE_S1, &pgtbl_cfg, qcom_domain);
243 	if (!pgtbl_ops) {
244 		dev_err(qcom_iommu->dev, "failed to allocate pagetable ops\n");
245 		ret = -ENOMEM;
246 		goto out_clear_iommu;
247 	}
248 
249 	domain->geometry.aperture_end = (1ULL << pgtbl_cfg.ias) - 1;
250 	domain->geometry.force_aperture = true;
251 
252 	for (i = 0; i < fwspec->num_ids; i++) {
253 		struct qcom_iommu_ctx *ctx = to_ctx(qcom_domain, fwspec->ids[i]);
254 
255 		if (!ctx->secure_init) {
256 			ret = qcom_scm_restore_sec_cfg(qcom_iommu->sec_id, ctx->asid);
257 			if (ret) {
258 				dev_err(qcom_iommu->dev, "secure init failed: %d\n", ret);
259 				goto out_clear_iommu;
260 			}
261 			ctx->secure_init = true;
262 		}
263 
264 		/* Secured QSMMU-500/QSMMU-v2 contexts cannot be programmed */
265 		if (ctx->secured_ctx) {
266 			ctx->domain = domain;
267 			continue;
268 		}
269 
270 		/* Disable context bank before programming */
271 		iommu_writel(ctx, ARM_SMMU_CB_SCTLR, 0);
272 
273 		/* Clear context bank fault address fault status registers */
274 		iommu_writel(ctx, ARM_SMMU_CB_FAR, 0);
275 		iommu_writel(ctx, ARM_SMMU_CB_FSR, ARM_SMMU_CB_FSR_FAULT);
276 
277 		/* TTBRs */
278 		iommu_writeq(ctx, ARM_SMMU_CB_TTBR0,
279 				pgtbl_cfg.arm_lpae_s1_cfg.ttbr |
280 				FIELD_PREP(ARM_SMMU_TTBRn_ASID, ctx->asid));
281 		iommu_writeq(ctx, ARM_SMMU_CB_TTBR1, 0);
282 
283 		/* TCR */
284 		iommu_writel(ctx, ARM_SMMU_CB_TCR2,
285 				arm_smmu_lpae_tcr2(&pgtbl_cfg));
286 		iommu_writel(ctx, ARM_SMMU_CB_TCR,
287 			     arm_smmu_lpae_tcr(&pgtbl_cfg) | ARM_SMMU_TCR_EAE);
288 
289 		/* MAIRs (stage-1 only) */
290 		iommu_writel(ctx, ARM_SMMU_CB_S1_MAIR0,
291 				pgtbl_cfg.arm_lpae_s1_cfg.mair);
292 		iommu_writel(ctx, ARM_SMMU_CB_S1_MAIR1,
293 				pgtbl_cfg.arm_lpae_s1_cfg.mair >> 32);
294 
295 		/* SCTLR */
296 		reg = ARM_SMMU_SCTLR_CFIE | ARM_SMMU_SCTLR_CFRE |
297 		      ARM_SMMU_SCTLR_AFE | ARM_SMMU_SCTLR_TRE |
298 		      ARM_SMMU_SCTLR_M | ARM_SMMU_SCTLR_S1_ASIDPNE |
299 		      ARM_SMMU_SCTLR_CFCFG;
300 
301 		if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
302 			reg |= ARM_SMMU_SCTLR_E;
303 
304 		iommu_writel(ctx, ARM_SMMU_CB_SCTLR, reg);
305 
306 		ctx->domain = domain;
307 	}
308 
309 	mutex_unlock(&qcom_domain->init_mutex);
310 
311 	/* Publish page table ops for map/unmap */
312 	qcom_domain->pgtbl_ops = pgtbl_ops;
313 
314 	return 0;
315 
316 out_clear_iommu:
317 	qcom_domain->iommu = NULL;
318 out_unlock:
319 	mutex_unlock(&qcom_domain->init_mutex);
320 	return ret;
321 }
322 
qcom_iommu_domain_alloc_paging(struct device * dev)323 static struct iommu_domain *qcom_iommu_domain_alloc_paging(struct device *dev)
324 {
325 	struct qcom_iommu_domain *qcom_domain;
326 
327 	/*
328 	 * Allocate the domain and initialise some of its data structures.
329 	 * We can't really do anything meaningful until we've added a
330 	 * master.
331 	 */
332 	qcom_domain = kzalloc(sizeof(*qcom_domain), GFP_KERNEL);
333 	if (!qcom_domain)
334 		return NULL;
335 
336 	mutex_init(&qcom_domain->init_mutex);
337 	spin_lock_init(&qcom_domain->pgtbl_lock);
338 	qcom_domain->domain.pgsize_bitmap = SZ_4K;
339 
340 	return &qcom_domain->domain;
341 }
342 
qcom_iommu_domain_free(struct iommu_domain * domain)343 static void qcom_iommu_domain_free(struct iommu_domain *domain)
344 {
345 	struct qcom_iommu_domain *qcom_domain = to_qcom_iommu_domain(domain);
346 
347 	if (qcom_domain->iommu) {
348 		/*
349 		 * NOTE: unmap can be called after client device is powered
350 		 * off, for example, with GPUs or anything involving dma-buf.
351 		 * So we cannot rely on the device_link.  Make sure the IOMMU
352 		 * is on to avoid unclocked accesses in the TLB inv path:
353 		 */
354 		pm_runtime_get_sync(qcom_domain->iommu->dev);
355 		free_io_pgtable_ops(qcom_domain->pgtbl_ops);
356 		pm_runtime_put_sync(qcom_domain->iommu->dev);
357 	}
358 
359 	kfree(qcom_domain);
360 }
361 
qcom_iommu_attach_dev(struct iommu_domain * domain,struct device * dev)362 static int qcom_iommu_attach_dev(struct iommu_domain *domain, struct device *dev)
363 {
364 	struct qcom_iommu_dev *qcom_iommu = dev_iommu_priv_get(dev);
365 	struct qcom_iommu_domain *qcom_domain = to_qcom_iommu_domain(domain);
366 	int ret;
367 
368 	if (!qcom_iommu) {
369 		dev_err(dev, "cannot attach to IOMMU, is it on the same bus?\n");
370 		return -ENXIO;
371 	}
372 
373 	/* Ensure that the domain is finalized */
374 	pm_runtime_get_sync(qcom_iommu->dev);
375 	ret = qcom_iommu_init_domain(domain, qcom_iommu, dev);
376 	pm_runtime_put_sync(qcom_iommu->dev);
377 	if (ret < 0)
378 		return ret;
379 
380 	/*
381 	 * Sanity check the domain. We don't support domains across
382 	 * different IOMMUs.
383 	 */
384 	if (qcom_domain->iommu != qcom_iommu)
385 		return -EINVAL;
386 
387 	return 0;
388 }
389 
qcom_iommu_identity_attach(struct iommu_domain * identity_domain,struct device * dev)390 static int qcom_iommu_identity_attach(struct iommu_domain *identity_domain,
391 				      struct device *dev)
392 {
393 	struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
394 	struct qcom_iommu_domain *qcom_domain;
395 	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
396 	struct qcom_iommu_dev *qcom_iommu = dev_iommu_priv_get(dev);
397 	unsigned int i;
398 
399 	if (domain == identity_domain || !domain)
400 		return 0;
401 
402 	qcom_domain = to_qcom_iommu_domain(domain);
403 	if (WARN_ON(!qcom_domain->iommu))
404 		return -EINVAL;
405 
406 	pm_runtime_get_sync(qcom_iommu->dev);
407 	for (i = 0; i < fwspec->num_ids; i++) {
408 		struct qcom_iommu_ctx *ctx = to_ctx(qcom_domain, fwspec->ids[i]);
409 
410 		/* Disable the context bank: */
411 		iommu_writel(ctx, ARM_SMMU_CB_SCTLR, 0);
412 
413 		ctx->domain = NULL;
414 	}
415 	pm_runtime_put_sync(qcom_iommu->dev);
416 	return 0;
417 }
418 
419 static struct iommu_domain_ops qcom_iommu_identity_ops = {
420 	.attach_dev = qcom_iommu_identity_attach,
421 };
422 
423 static struct iommu_domain qcom_iommu_identity_domain = {
424 	.type = IOMMU_DOMAIN_IDENTITY,
425 	.ops = &qcom_iommu_identity_ops,
426 };
427 
qcom_iommu_map(struct iommu_domain * domain,unsigned long iova,phys_addr_t paddr,size_t pgsize,size_t pgcount,int prot,gfp_t gfp,size_t * mapped)428 static int qcom_iommu_map(struct iommu_domain *domain, unsigned long iova,
429 			  phys_addr_t paddr, size_t pgsize, size_t pgcount,
430 			  int prot, gfp_t gfp, size_t *mapped)
431 {
432 	int ret;
433 	unsigned long flags;
434 	struct qcom_iommu_domain *qcom_domain = to_qcom_iommu_domain(domain);
435 	struct io_pgtable_ops *ops = qcom_domain->pgtbl_ops;
436 
437 	if (!ops)
438 		return -ENODEV;
439 
440 	spin_lock_irqsave(&qcom_domain->pgtbl_lock, flags);
441 	ret = ops->map_pages(ops, iova, paddr, pgsize, pgcount, prot, GFP_ATOMIC, mapped);
442 	spin_unlock_irqrestore(&qcom_domain->pgtbl_lock, flags);
443 	return ret;
444 }
445 
qcom_iommu_unmap(struct iommu_domain * domain,unsigned long iova,size_t pgsize,size_t pgcount,struct iommu_iotlb_gather * gather)446 static size_t qcom_iommu_unmap(struct iommu_domain *domain, unsigned long iova,
447 			       size_t pgsize, size_t pgcount,
448 			       struct iommu_iotlb_gather *gather)
449 {
450 	size_t ret;
451 	unsigned long flags;
452 	struct qcom_iommu_domain *qcom_domain = to_qcom_iommu_domain(domain);
453 	struct io_pgtable_ops *ops = qcom_domain->pgtbl_ops;
454 
455 	if (!ops)
456 		return 0;
457 
458 	/* NOTE: unmap can be called after client device is powered off,
459 	 * for example, with GPUs or anything involving dma-buf.  So we
460 	 * cannot rely on the device_link.  Make sure the IOMMU is on to
461 	 * avoid unclocked accesses in the TLB inv path:
462 	 */
463 	pm_runtime_get_sync(qcom_domain->iommu->dev);
464 	spin_lock_irqsave(&qcom_domain->pgtbl_lock, flags);
465 	ret = ops->unmap_pages(ops, iova, pgsize, pgcount, gather);
466 	spin_unlock_irqrestore(&qcom_domain->pgtbl_lock, flags);
467 	pm_runtime_put_sync(qcom_domain->iommu->dev);
468 
469 	return ret;
470 }
471 
qcom_iommu_flush_iotlb_all(struct iommu_domain * domain)472 static void qcom_iommu_flush_iotlb_all(struct iommu_domain *domain)
473 {
474 	struct qcom_iommu_domain *qcom_domain = to_qcom_iommu_domain(domain);
475 	struct io_pgtable *pgtable = container_of(qcom_domain->pgtbl_ops,
476 						  struct io_pgtable, ops);
477 	if (!qcom_domain->pgtbl_ops)
478 		return;
479 
480 	pm_runtime_get_sync(qcom_domain->iommu->dev);
481 	qcom_iommu_tlb_sync(pgtable->cookie);
482 	pm_runtime_put_sync(qcom_domain->iommu->dev);
483 }
484 
qcom_iommu_iotlb_sync(struct iommu_domain * domain,struct iommu_iotlb_gather * gather)485 static void qcom_iommu_iotlb_sync(struct iommu_domain *domain,
486 				  struct iommu_iotlb_gather *gather)
487 {
488 	qcom_iommu_flush_iotlb_all(domain);
489 }
490 
qcom_iommu_iova_to_phys(struct iommu_domain * domain,dma_addr_t iova)491 static phys_addr_t qcom_iommu_iova_to_phys(struct iommu_domain *domain,
492 					   dma_addr_t iova)
493 {
494 	phys_addr_t ret;
495 	unsigned long flags;
496 	struct qcom_iommu_domain *qcom_domain = to_qcom_iommu_domain(domain);
497 	struct io_pgtable_ops *ops = qcom_domain->pgtbl_ops;
498 
499 	if (!ops)
500 		return 0;
501 
502 	spin_lock_irqsave(&qcom_domain->pgtbl_lock, flags);
503 	ret = ops->iova_to_phys(ops, iova);
504 	spin_unlock_irqrestore(&qcom_domain->pgtbl_lock, flags);
505 
506 	return ret;
507 }
508 
qcom_iommu_capable(struct device * dev,enum iommu_cap cap)509 static bool qcom_iommu_capable(struct device *dev, enum iommu_cap cap)
510 {
511 	switch (cap) {
512 	case IOMMU_CAP_CACHE_COHERENCY:
513 		/*
514 		 * Return true here as the SMMU can always send out coherent
515 		 * requests.
516 		 */
517 		return true;
518 	case IOMMU_CAP_NOEXEC:
519 		return true;
520 	default:
521 		return false;
522 	}
523 }
524 
qcom_iommu_probe_device(struct device * dev)525 static struct iommu_device *qcom_iommu_probe_device(struct device *dev)
526 {
527 	struct qcom_iommu_dev *qcom_iommu = dev_iommu_priv_get(dev);
528 	struct device_link *link;
529 
530 	if (!qcom_iommu)
531 		return ERR_PTR(-ENODEV);
532 
533 	/*
534 	 * Establish the link between iommu and master, so that the
535 	 * iommu gets runtime enabled/disabled as per the master's
536 	 * needs.
537 	 */
538 	link = device_link_add(dev, qcom_iommu->dev, DL_FLAG_PM_RUNTIME);
539 	if (!link) {
540 		dev_err(qcom_iommu->dev, "Unable to create device link between %s and %s\n",
541 			dev_name(qcom_iommu->dev), dev_name(dev));
542 		return ERR_PTR(-ENODEV);
543 	}
544 
545 	return &qcom_iommu->iommu;
546 }
547 
qcom_iommu_of_xlate(struct device * dev,const struct of_phandle_args * args)548 static int qcom_iommu_of_xlate(struct device *dev,
549 			       const struct of_phandle_args *args)
550 {
551 	struct qcom_iommu_dev *qcom_iommu;
552 	struct platform_device *iommu_pdev;
553 	unsigned asid = args->args[0];
554 
555 	if (args->args_count != 1) {
556 		dev_err(dev, "incorrect number of iommu params found for %s "
557 			"(found %d, expected 1)\n",
558 			args->np->full_name, args->args_count);
559 		return -EINVAL;
560 	}
561 
562 	iommu_pdev = of_find_device_by_node(args->np);
563 	if (WARN_ON(!iommu_pdev))
564 		return -EINVAL;
565 
566 	qcom_iommu = platform_get_drvdata(iommu_pdev);
567 
568 	/* make sure the asid specified in dt is valid, so we don't have
569 	 * to sanity check this elsewhere:
570 	 */
571 	if (WARN_ON(asid > qcom_iommu->max_asid) ||
572 	    WARN_ON(qcom_iommu->ctxs[asid] == NULL)) {
573 		put_device(&iommu_pdev->dev);
574 		return -EINVAL;
575 	}
576 
577 	if (!dev_iommu_priv_get(dev)) {
578 		dev_iommu_priv_set(dev, qcom_iommu);
579 	} else {
580 		/* make sure devices iommus dt node isn't referring to
581 		 * multiple different iommu devices.  Multiple context
582 		 * banks are ok, but multiple devices are not:
583 		 */
584 		if (WARN_ON(qcom_iommu != dev_iommu_priv_get(dev))) {
585 			put_device(&iommu_pdev->dev);
586 			return -EINVAL;
587 		}
588 	}
589 
590 	return iommu_fwspec_add_ids(dev, &asid, 1);
591 }
592 
593 static const struct iommu_ops qcom_iommu_ops = {
594 	.identity_domain = &qcom_iommu_identity_domain,
595 	.capable	= qcom_iommu_capable,
596 	.domain_alloc_paging = qcom_iommu_domain_alloc_paging,
597 	.probe_device	= qcom_iommu_probe_device,
598 	.device_group	= generic_device_group,
599 	.of_xlate	= qcom_iommu_of_xlate,
600 	.default_domain_ops = &(const struct iommu_domain_ops) {
601 		.attach_dev	= qcom_iommu_attach_dev,
602 		.map_pages	= qcom_iommu_map,
603 		.unmap_pages	= qcom_iommu_unmap,
604 		.flush_iotlb_all = qcom_iommu_flush_iotlb_all,
605 		.iotlb_sync	= qcom_iommu_iotlb_sync,
606 		.iova_to_phys	= qcom_iommu_iova_to_phys,
607 		.free		= qcom_iommu_domain_free,
608 	}
609 };
610 
qcom_iommu_sec_ptbl_init(struct device * dev)611 static int qcom_iommu_sec_ptbl_init(struct device *dev)
612 {
613 	size_t psize = 0;
614 	unsigned int spare = 0;
615 	void *cpu_addr;
616 	dma_addr_t paddr;
617 	unsigned long attrs;
618 	static bool allocated = false;
619 	int ret;
620 
621 	if (allocated)
622 		return 0;
623 
624 	ret = qcom_scm_iommu_secure_ptbl_size(spare, &psize);
625 	if (ret) {
626 		dev_err(dev, "failed to get iommu secure pgtable size (%d)\n",
627 			ret);
628 		return ret;
629 	}
630 
631 	dev_info(dev, "iommu sec: pgtable size: %zu\n", psize);
632 
633 	attrs = DMA_ATTR_NO_KERNEL_MAPPING;
634 
635 	cpu_addr = dma_alloc_attrs(dev, psize, &paddr, GFP_KERNEL, attrs);
636 	if (!cpu_addr) {
637 		dev_err(dev, "failed to allocate %zu bytes for pgtable\n",
638 			psize);
639 		return -ENOMEM;
640 	}
641 
642 	ret = qcom_scm_iommu_secure_ptbl_init(paddr, psize, spare);
643 	if (ret) {
644 		dev_err(dev, "failed to init iommu pgtable (%d)\n", ret);
645 		goto free_mem;
646 	}
647 
648 	allocated = true;
649 	return 0;
650 
651 free_mem:
652 	dma_free_attrs(dev, psize, cpu_addr, paddr, attrs);
653 	return ret;
654 }
655 
get_asid(const struct device_node * np)656 static int get_asid(const struct device_node *np)
657 {
658 	u32 reg, val;
659 	int asid;
660 
661 	/* read the "reg" property directly to get the relative address
662 	 * of the context bank, and calculate the asid from that:
663 	 */
664 	if (of_property_read_u32_index(np, "reg", 0, &reg))
665 		return -ENODEV;
666 
667 	/*
668 	 * Context banks are 0x1000 apart but, in some cases, the ASID
669 	 * number doesn't match to this logic and needs to be passed
670 	 * from the DT configuration explicitly.
671 	 */
672 	if (!of_property_read_u32(np, "qcom,ctx-asid", &val))
673 		asid = val;
674 	else
675 		asid = reg / 0x1000;
676 
677 	return asid;
678 }
679 
qcom_iommu_ctx_probe(struct platform_device * pdev)680 static int qcom_iommu_ctx_probe(struct platform_device *pdev)
681 {
682 	struct qcom_iommu_ctx *ctx;
683 	struct device *dev = &pdev->dev;
684 	struct qcom_iommu_dev *qcom_iommu = dev_get_drvdata(dev->parent);
685 	int ret, irq;
686 
687 	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
688 	if (!ctx)
689 		return -ENOMEM;
690 
691 	ctx->dev = dev;
692 	platform_set_drvdata(pdev, ctx);
693 
694 	ctx->base = devm_platform_ioremap_resource(pdev, 0);
695 	if (IS_ERR(ctx->base))
696 		return PTR_ERR(ctx->base);
697 
698 	irq = platform_get_irq(pdev, 0);
699 	if (irq < 0)
700 		return irq;
701 
702 	if (of_device_is_compatible(dev->of_node, "qcom,msm-iommu-v2-sec"))
703 		ctx->secured_ctx = true;
704 
705 	/* clear IRQs before registering fault handler, just in case the
706 	 * boot-loader left us a surprise:
707 	 */
708 	if (!ctx->secured_ctx)
709 		iommu_writel(ctx, ARM_SMMU_CB_FSR, iommu_readl(ctx, ARM_SMMU_CB_FSR));
710 
711 	ret = devm_request_irq(dev, irq,
712 			       qcom_iommu_fault,
713 			       IRQF_SHARED,
714 			       "qcom-iommu-fault",
715 			       ctx);
716 	if (ret) {
717 		dev_err(dev, "failed to request IRQ %u\n", irq);
718 		return ret;
719 	}
720 
721 	ret = get_asid(dev->of_node);
722 	if (ret < 0) {
723 		dev_err(dev, "missing reg property\n");
724 		return ret;
725 	}
726 
727 	ctx->asid = ret;
728 
729 	dev_dbg(dev, "found asid %u\n", ctx->asid);
730 
731 	qcom_iommu->ctxs[ctx->asid] = ctx;
732 
733 	return 0;
734 }
735 
qcom_iommu_ctx_remove(struct platform_device * pdev)736 static void qcom_iommu_ctx_remove(struct platform_device *pdev)
737 {
738 	struct qcom_iommu_dev *qcom_iommu = dev_get_drvdata(pdev->dev.parent);
739 	struct qcom_iommu_ctx *ctx = platform_get_drvdata(pdev);
740 
741 	platform_set_drvdata(pdev, NULL);
742 
743 	qcom_iommu->ctxs[ctx->asid] = NULL;
744 }
745 
746 static const struct of_device_id ctx_of_match[] = {
747 	{ .compatible = "qcom,msm-iommu-v1-ns" },
748 	{ .compatible = "qcom,msm-iommu-v1-sec" },
749 	{ .compatible = "qcom,msm-iommu-v2-ns" },
750 	{ .compatible = "qcom,msm-iommu-v2-sec" },
751 	{ /* sentinel */ }
752 };
753 
754 static struct platform_driver qcom_iommu_ctx_driver = {
755 	.driver	= {
756 		.name		= "qcom-iommu-ctx",
757 		.of_match_table	= ctx_of_match,
758 	},
759 	.probe	= qcom_iommu_ctx_probe,
760 	.remove = qcom_iommu_ctx_remove,
761 };
762 
qcom_iommu_has_secure_context(struct qcom_iommu_dev * qcom_iommu)763 static bool qcom_iommu_has_secure_context(struct qcom_iommu_dev *qcom_iommu)
764 {
765 	struct device_node *child;
766 
767 	for_each_child_of_node(qcom_iommu->dev->of_node, child) {
768 		if (of_device_is_compatible(child, "qcom,msm-iommu-v1-sec") ||
769 		    of_device_is_compatible(child, "qcom,msm-iommu-v2-sec")) {
770 			of_node_put(child);
771 			return true;
772 		}
773 	}
774 
775 	return false;
776 }
777 
qcom_iommu_device_probe(struct platform_device * pdev)778 static int qcom_iommu_device_probe(struct platform_device *pdev)
779 {
780 	struct device_node *child;
781 	struct qcom_iommu_dev *qcom_iommu;
782 	struct device *dev = &pdev->dev;
783 	struct resource *res;
784 	struct clk *clk;
785 	int ret, max_asid = 0;
786 
787 	/* find the max asid (which is 1:1 to ctx bank idx), so we know how
788 	 * many child ctx devices we have:
789 	 */
790 	for_each_child_of_node(dev->of_node, child)
791 		max_asid = max(max_asid, get_asid(child));
792 
793 	qcom_iommu = devm_kzalloc(dev, struct_size(qcom_iommu, ctxs, max_asid + 1),
794 				  GFP_KERNEL);
795 	if (!qcom_iommu)
796 		return -ENOMEM;
797 	qcom_iommu->max_asid = max_asid;
798 	qcom_iommu->dev = dev;
799 
800 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
801 	if (res) {
802 		qcom_iommu->local_base = devm_ioremap_resource(dev, res);
803 		if (IS_ERR(qcom_iommu->local_base))
804 			return PTR_ERR(qcom_iommu->local_base);
805 	}
806 
807 	clk = devm_clk_get(dev, "iface");
808 	if (IS_ERR(clk)) {
809 		dev_err(dev, "failed to get iface clock\n");
810 		return PTR_ERR(clk);
811 	}
812 	qcom_iommu->clks[CLK_IFACE].clk = clk;
813 
814 	clk = devm_clk_get(dev, "bus");
815 	if (IS_ERR(clk)) {
816 		dev_err(dev, "failed to get bus clock\n");
817 		return PTR_ERR(clk);
818 	}
819 	qcom_iommu->clks[CLK_BUS].clk = clk;
820 
821 	clk = devm_clk_get_optional(dev, "tbu");
822 	if (IS_ERR(clk)) {
823 		dev_err(dev, "failed to get tbu clock\n");
824 		return PTR_ERR(clk);
825 	}
826 	qcom_iommu->clks[CLK_TBU].clk = clk;
827 
828 	if (of_property_read_u32(dev->of_node, "qcom,iommu-secure-id",
829 				 &qcom_iommu->sec_id)) {
830 		dev_err(dev, "missing qcom,iommu-secure-id property\n");
831 		return -ENODEV;
832 	}
833 
834 	if (qcom_iommu_has_secure_context(qcom_iommu)) {
835 		ret = qcom_iommu_sec_ptbl_init(dev);
836 		if (ret) {
837 			dev_err(dev, "cannot init secure pg table(%d)\n", ret);
838 			return ret;
839 		}
840 	}
841 
842 	platform_set_drvdata(pdev, qcom_iommu);
843 
844 	pm_runtime_enable(dev);
845 
846 	/* register context bank devices, which are child nodes: */
847 	ret = devm_of_platform_populate(dev);
848 	if (ret) {
849 		dev_err(dev, "Failed to populate iommu contexts\n");
850 		goto err_pm_disable;
851 	}
852 
853 	ret = iommu_device_sysfs_add(&qcom_iommu->iommu, dev, NULL,
854 				     dev_name(dev));
855 	if (ret) {
856 		dev_err(dev, "Failed to register iommu in sysfs\n");
857 		goto err_pm_disable;
858 	}
859 
860 	ret = iommu_device_register(&qcom_iommu->iommu, &qcom_iommu_ops, dev);
861 	if (ret) {
862 		dev_err(dev, "Failed to register iommu\n");
863 		goto err_pm_disable;
864 	}
865 
866 	if (qcom_iommu->local_base) {
867 		pm_runtime_get_sync(dev);
868 		writel_relaxed(0xffffffff, qcom_iommu->local_base + SMMU_INTR_SEL_NS);
869 		pm_runtime_put_sync(dev);
870 	}
871 
872 	return 0;
873 
874 err_pm_disable:
875 	pm_runtime_disable(dev);
876 	return ret;
877 }
878 
qcom_iommu_device_remove(struct platform_device * pdev)879 static void qcom_iommu_device_remove(struct platform_device *pdev)
880 {
881 	struct qcom_iommu_dev *qcom_iommu = platform_get_drvdata(pdev);
882 
883 	pm_runtime_force_suspend(&pdev->dev);
884 	platform_set_drvdata(pdev, NULL);
885 	iommu_device_sysfs_remove(&qcom_iommu->iommu);
886 	iommu_device_unregister(&qcom_iommu->iommu);
887 }
888 
qcom_iommu_resume(struct device * dev)889 static int __maybe_unused qcom_iommu_resume(struct device *dev)
890 {
891 	struct qcom_iommu_dev *qcom_iommu = dev_get_drvdata(dev);
892 	int ret;
893 
894 	ret = clk_bulk_prepare_enable(CLK_NUM, qcom_iommu->clks);
895 	if (ret < 0)
896 		return ret;
897 
898 	if (dev->pm_domain)
899 		return qcom_scm_restore_sec_cfg(qcom_iommu->sec_id, 0);
900 
901 	return ret;
902 }
903 
qcom_iommu_suspend(struct device * dev)904 static int __maybe_unused qcom_iommu_suspend(struct device *dev)
905 {
906 	struct qcom_iommu_dev *qcom_iommu = dev_get_drvdata(dev);
907 
908 	clk_bulk_disable_unprepare(CLK_NUM, qcom_iommu->clks);
909 
910 	return 0;
911 }
912 
913 static const struct dev_pm_ops qcom_iommu_pm_ops = {
914 	SET_RUNTIME_PM_OPS(qcom_iommu_suspend, qcom_iommu_resume, NULL)
915 	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
916 				pm_runtime_force_resume)
917 };
918 
919 static const struct of_device_id qcom_iommu_of_match[] = {
920 	{ .compatible = "qcom,msm-iommu-v1" },
921 	{ .compatible = "qcom,msm-iommu-v2" },
922 	{ /* sentinel */ }
923 };
924 
925 static struct platform_driver qcom_iommu_driver = {
926 	.driver	= {
927 		.name		= "qcom-iommu",
928 		.of_match_table	= qcom_iommu_of_match,
929 		.pm		= &qcom_iommu_pm_ops,
930 	},
931 	.probe	= qcom_iommu_device_probe,
932 	.remove = qcom_iommu_device_remove,
933 };
934 
qcom_iommu_init(void)935 static int __init qcom_iommu_init(void)
936 {
937 	int ret;
938 
939 	ret = platform_driver_register(&qcom_iommu_ctx_driver);
940 	if (ret)
941 		return ret;
942 
943 	ret = platform_driver_register(&qcom_iommu_driver);
944 	if (ret)
945 		platform_driver_unregister(&qcom_iommu_ctx_driver);
946 
947 	return ret;
948 }
949 device_initcall(qcom_iommu_init);
950