xref: /linux/drivers/iommu/arm/arm-smmu/qcom_iommu.c (revision ce5cfb0fa20dc6454da039612e34325b7b4a8243)
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,struct iommu_domain * old)362 static int qcom_iommu_attach_dev(struct iommu_domain *domain,
363 				 struct device *dev, struct iommu_domain *old)
364 {
365 	struct qcom_iommu_dev *qcom_iommu = dev_iommu_priv_get(dev);
366 	struct qcom_iommu_domain *qcom_domain = to_qcom_iommu_domain(domain);
367 	int ret;
368 
369 	if (!qcom_iommu) {
370 		dev_err(dev, "cannot attach to IOMMU, is it on the same bus?\n");
371 		return -ENXIO;
372 	}
373 
374 	/* Ensure that the domain is finalized */
375 	pm_runtime_get_sync(qcom_iommu->dev);
376 	ret = qcom_iommu_init_domain(domain, qcom_iommu, dev);
377 	pm_runtime_put_sync(qcom_iommu->dev);
378 	if (ret < 0)
379 		return ret;
380 
381 	/*
382 	 * Sanity check the domain. We don't support domains across
383 	 * different IOMMUs.
384 	 */
385 	if (qcom_domain->iommu != qcom_iommu)
386 		return -EINVAL;
387 
388 	return 0;
389 }
390 
qcom_iommu_identity_attach(struct iommu_domain * identity_domain,struct device * dev,struct iommu_domain * old)391 static int qcom_iommu_identity_attach(struct iommu_domain *identity_domain,
392 				      struct device *dev,
393 				      struct iommu_domain *old)
394 {
395 	struct qcom_iommu_domain *qcom_domain;
396 	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
397 	struct qcom_iommu_dev *qcom_iommu = dev_iommu_priv_get(dev);
398 	unsigned int i;
399 
400 	if (old == identity_domain || !old)
401 		return 0;
402 
403 	qcom_domain = to_qcom_iommu_domain(old);
404 	if (WARN_ON(!qcom_domain->iommu))
405 		return -EINVAL;
406 
407 	pm_runtime_get_sync(qcom_iommu->dev);
408 	for (i = 0; i < fwspec->num_ids; i++) {
409 		struct qcom_iommu_ctx *ctx = to_ctx(qcom_domain, fwspec->ids[i]);
410 
411 		/* Disable the context bank: */
412 		iommu_writel(ctx, ARM_SMMU_CB_SCTLR, 0);
413 
414 		ctx->domain = NULL;
415 	}
416 	pm_runtime_put_sync(qcom_iommu->dev);
417 	return 0;
418 }
419 
420 static struct iommu_domain_ops qcom_iommu_identity_ops = {
421 	.attach_dev = qcom_iommu_identity_attach,
422 };
423 
424 static struct iommu_domain qcom_iommu_identity_domain = {
425 	.type = IOMMU_DOMAIN_IDENTITY,
426 	.ops = &qcom_iommu_identity_ops,
427 };
428 
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)429 static int qcom_iommu_map(struct iommu_domain *domain, unsigned long iova,
430 			  phys_addr_t paddr, size_t pgsize, size_t pgcount,
431 			  int prot, gfp_t gfp, size_t *mapped)
432 {
433 	int ret;
434 	unsigned long flags;
435 	struct qcom_iommu_domain *qcom_domain = to_qcom_iommu_domain(domain);
436 	struct io_pgtable_ops *ops = qcom_domain->pgtbl_ops;
437 
438 	if (!ops)
439 		return -ENODEV;
440 
441 	spin_lock_irqsave(&qcom_domain->pgtbl_lock, flags);
442 	ret = ops->map_pages(ops, iova, paddr, pgsize, pgcount, prot, GFP_ATOMIC, mapped);
443 	spin_unlock_irqrestore(&qcom_domain->pgtbl_lock, flags);
444 	return ret;
445 }
446 
qcom_iommu_unmap(struct iommu_domain * domain,unsigned long iova,size_t pgsize,size_t pgcount,struct iommu_iotlb_gather * gather)447 static size_t qcom_iommu_unmap(struct iommu_domain *domain, unsigned long iova,
448 			       size_t pgsize, size_t pgcount,
449 			       struct iommu_iotlb_gather *gather)
450 {
451 	size_t ret;
452 	unsigned long flags;
453 	struct qcom_iommu_domain *qcom_domain = to_qcom_iommu_domain(domain);
454 	struct io_pgtable_ops *ops = qcom_domain->pgtbl_ops;
455 
456 	if (!ops)
457 		return 0;
458 
459 	/* NOTE: unmap can be called after client device is powered off,
460 	 * for example, with GPUs or anything involving dma-buf.  So we
461 	 * cannot rely on the device_link.  Make sure the IOMMU is on to
462 	 * avoid unclocked accesses in the TLB inv path:
463 	 */
464 	pm_runtime_get_sync(qcom_domain->iommu->dev);
465 	spin_lock_irqsave(&qcom_domain->pgtbl_lock, flags);
466 	ret = ops->unmap_pages(ops, iova, pgsize, pgcount, gather);
467 	spin_unlock_irqrestore(&qcom_domain->pgtbl_lock, flags);
468 	pm_runtime_put_sync(qcom_domain->iommu->dev);
469 
470 	return ret;
471 }
472 
qcom_iommu_flush_iotlb_all(struct iommu_domain * domain)473 static void qcom_iommu_flush_iotlb_all(struct iommu_domain *domain)
474 {
475 	struct qcom_iommu_domain *qcom_domain = to_qcom_iommu_domain(domain);
476 	struct io_pgtable *pgtable = container_of(qcom_domain->pgtbl_ops,
477 						  struct io_pgtable, ops);
478 	if (!qcom_domain->pgtbl_ops)
479 		return;
480 
481 	pm_runtime_get_sync(qcom_domain->iommu->dev);
482 	qcom_iommu_tlb_sync(pgtable->cookie);
483 	pm_runtime_put_sync(qcom_domain->iommu->dev);
484 }
485 
qcom_iommu_iotlb_sync(struct iommu_domain * domain,struct iommu_iotlb_gather * gather)486 static void qcom_iommu_iotlb_sync(struct iommu_domain *domain,
487 				  struct iommu_iotlb_gather *gather)
488 {
489 	qcom_iommu_flush_iotlb_all(domain);
490 }
491 
qcom_iommu_iova_to_phys(struct iommu_domain * domain,dma_addr_t iova)492 static phys_addr_t qcom_iommu_iova_to_phys(struct iommu_domain *domain,
493 					   dma_addr_t iova)
494 {
495 	phys_addr_t ret;
496 	unsigned long flags;
497 	struct qcom_iommu_domain *qcom_domain = to_qcom_iommu_domain(domain);
498 	struct io_pgtable_ops *ops = qcom_domain->pgtbl_ops;
499 
500 	if (!ops)
501 		return 0;
502 
503 	spin_lock_irqsave(&qcom_domain->pgtbl_lock, flags);
504 	ret = ops->iova_to_phys(ops, iova);
505 	spin_unlock_irqrestore(&qcom_domain->pgtbl_lock, flags);
506 
507 	return ret;
508 }
509 
qcom_iommu_capable(struct device * dev,enum iommu_cap cap)510 static bool qcom_iommu_capable(struct device *dev, enum iommu_cap cap)
511 {
512 	switch (cap) {
513 	case IOMMU_CAP_CACHE_COHERENCY:
514 		/*
515 		 * Return true here as the SMMU can always send out coherent
516 		 * requests.
517 		 */
518 		return true;
519 	case IOMMU_CAP_NOEXEC:
520 		return true;
521 	default:
522 		return false;
523 	}
524 }
525 
qcom_iommu_probe_device(struct device * dev)526 static struct iommu_device *qcom_iommu_probe_device(struct device *dev)
527 {
528 	struct qcom_iommu_dev *qcom_iommu = dev_iommu_priv_get(dev);
529 	struct device_link *link;
530 
531 	if (!qcom_iommu)
532 		return ERR_PTR(-ENODEV);
533 
534 	/*
535 	 * Establish the link between iommu and master, so that the
536 	 * iommu gets runtime enabled/disabled as per the master's
537 	 * needs.
538 	 */
539 	link = device_link_add(dev, qcom_iommu->dev, DL_FLAG_PM_RUNTIME);
540 	if (!link) {
541 		dev_err(qcom_iommu->dev, "Unable to create device link between %s and %s\n",
542 			dev_name(qcom_iommu->dev), dev_name(dev));
543 		return ERR_PTR(-ENODEV);
544 	}
545 
546 	return &qcom_iommu->iommu;
547 }
548 
qcom_iommu_of_xlate(struct device * dev,const struct of_phandle_args * args)549 static int qcom_iommu_of_xlate(struct device *dev,
550 			       const struct of_phandle_args *args)
551 {
552 	struct qcom_iommu_dev *qcom_iommu;
553 	struct platform_device *iommu_pdev;
554 	unsigned asid = args->args[0];
555 
556 	if (args->args_count != 1) {
557 		dev_err(dev, "incorrect number of iommu params found for %s "
558 			"(found %d, expected 1)\n",
559 			args->np->full_name, args->args_count);
560 		return -EINVAL;
561 	}
562 
563 	iommu_pdev = of_find_device_by_node(args->np);
564 	if (WARN_ON(!iommu_pdev))
565 		return -EINVAL;
566 
567 	qcom_iommu = platform_get_drvdata(iommu_pdev);
568 
569 	put_device(&iommu_pdev->dev);
570 
571 	/* make sure the asid specified in dt is valid, so we don't have
572 	 * to sanity check this elsewhere:
573 	 */
574 	if (WARN_ON(asid > qcom_iommu->max_asid) ||
575 	    WARN_ON(qcom_iommu->ctxs[asid] == NULL))
576 		return -EINVAL;
577 
578 	if (!dev_iommu_priv_get(dev)) {
579 		dev_iommu_priv_set(dev, qcom_iommu);
580 	} else {
581 		/* make sure devices iommus dt node isn't referring to
582 		 * multiple different iommu devices.  Multiple context
583 		 * banks are ok, but multiple devices are not:
584 		 */
585 		if (WARN_ON(qcom_iommu != dev_iommu_priv_get(dev)))
586 			return -EINVAL;
587 	}
588 
589 	return iommu_fwspec_add_ids(dev, &asid, 1);
590 }
591 
592 static const struct iommu_ops qcom_iommu_ops = {
593 	.identity_domain = &qcom_iommu_identity_domain,
594 	.capable	= qcom_iommu_capable,
595 	.domain_alloc_paging = qcom_iommu_domain_alloc_paging,
596 	.probe_device	= qcom_iommu_probe_device,
597 	.device_group	= generic_device_group,
598 	.of_xlate	= qcom_iommu_of_xlate,
599 	.default_domain_ops = &(const struct iommu_domain_ops) {
600 		.attach_dev	= qcom_iommu_attach_dev,
601 		.map_pages	= qcom_iommu_map,
602 		.unmap_pages	= qcom_iommu_unmap,
603 		.flush_iotlb_all = qcom_iommu_flush_iotlb_all,
604 		.iotlb_sync	= qcom_iommu_iotlb_sync,
605 		.iova_to_phys	= qcom_iommu_iova_to_phys,
606 		.free		= qcom_iommu_domain_free,
607 	}
608 };
609 
qcom_iommu_sec_ptbl_init(struct device * dev)610 static int qcom_iommu_sec_ptbl_init(struct device *dev)
611 {
612 	size_t psize = 0;
613 	unsigned int spare = 0;
614 	void *cpu_addr;
615 	dma_addr_t paddr;
616 	unsigned long attrs;
617 	static bool allocated = false;
618 	int ret;
619 
620 	if (allocated)
621 		return 0;
622 
623 	ret = qcom_scm_iommu_secure_ptbl_size(spare, &psize);
624 	if (ret) {
625 		dev_err(dev, "failed to get iommu secure pgtable size (%d)\n",
626 			ret);
627 		return ret;
628 	}
629 
630 	dev_info(dev, "iommu sec: pgtable size: %zu\n", psize);
631 
632 	attrs = DMA_ATTR_NO_KERNEL_MAPPING;
633 
634 	cpu_addr = dma_alloc_attrs(dev, psize, &paddr, GFP_KERNEL, attrs);
635 	if (!cpu_addr) {
636 		dev_err(dev, "failed to allocate %zu bytes for pgtable\n",
637 			psize);
638 		return -ENOMEM;
639 	}
640 
641 	ret = qcom_scm_iommu_secure_ptbl_init(paddr, psize, spare);
642 	if (ret) {
643 		dev_err(dev, "failed to init iommu pgtable (%d)\n", ret);
644 		goto free_mem;
645 	}
646 
647 	allocated = true;
648 	return 0;
649 
650 free_mem:
651 	dma_free_attrs(dev, psize, cpu_addr, paddr, attrs);
652 	return ret;
653 }
654 
get_asid(const struct device_node * np)655 static int get_asid(const struct device_node *np)
656 {
657 	u32 reg, val;
658 	int asid;
659 
660 	/* read the "reg" property directly to get the relative address
661 	 * of the context bank, and calculate the asid from that:
662 	 */
663 	if (of_property_read_u32_index(np, "reg", 0, &reg))
664 		return -ENODEV;
665 
666 	/*
667 	 * Context banks are 0x1000 apart but, in some cases, the ASID
668 	 * number doesn't match to this logic and needs to be passed
669 	 * from the DT configuration explicitly.
670 	 */
671 	if (!of_property_read_u32(np, "qcom,ctx-asid", &val))
672 		asid = val;
673 	else
674 		asid = reg / 0x1000;
675 
676 	return asid;
677 }
678 
qcom_iommu_ctx_probe(struct platform_device * pdev)679 static int qcom_iommu_ctx_probe(struct platform_device *pdev)
680 {
681 	struct qcom_iommu_ctx *ctx;
682 	struct device *dev = &pdev->dev;
683 	struct qcom_iommu_dev *qcom_iommu = dev_get_drvdata(dev->parent);
684 	int ret, irq;
685 
686 	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
687 	if (!ctx)
688 		return -ENOMEM;
689 
690 	ctx->dev = dev;
691 	platform_set_drvdata(pdev, ctx);
692 
693 	ctx->base = devm_platform_ioremap_resource(pdev, 0);
694 	if (IS_ERR(ctx->base))
695 		return PTR_ERR(ctx->base);
696 
697 	irq = platform_get_irq(pdev, 0);
698 	if (irq < 0)
699 		return irq;
700 
701 	if (of_device_is_compatible(dev->of_node, "qcom,msm-iommu-v2-sec"))
702 		ctx->secured_ctx = true;
703 
704 	/* clear IRQs before registering fault handler, just in case the
705 	 * boot-loader left us a surprise:
706 	 */
707 	if (!ctx->secured_ctx)
708 		iommu_writel(ctx, ARM_SMMU_CB_FSR, iommu_readl(ctx, ARM_SMMU_CB_FSR));
709 
710 	ret = devm_request_irq(dev, irq,
711 			       qcom_iommu_fault,
712 			       IRQF_SHARED,
713 			       "qcom-iommu-fault",
714 			       ctx);
715 	if (ret) {
716 		dev_err(dev, "failed to request IRQ %u\n", irq);
717 		return ret;
718 	}
719 
720 	ret = get_asid(dev->of_node);
721 	if (ret < 0) {
722 		dev_err(dev, "missing reg property\n");
723 		return ret;
724 	}
725 
726 	ctx->asid = ret;
727 
728 	dev_dbg(dev, "found asid %u\n", ctx->asid);
729 
730 	qcom_iommu->ctxs[ctx->asid] = ctx;
731 
732 	return 0;
733 }
734 
qcom_iommu_ctx_remove(struct platform_device * pdev)735 static void qcom_iommu_ctx_remove(struct platform_device *pdev)
736 {
737 	struct qcom_iommu_dev *qcom_iommu = dev_get_drvdata(pdev->dev.parent);
738 	struct qcom_iommu_ctx *ctx = platform_get_drvdata(pdev);
739 
740 	platform_set_drvdata(pdev, NULL);
741 
742 	qcom_iommu->ctxs[ctx->asid] = NULL;
743 }
744 
745 static const struct of_device_id ctx_of_match[] = {
746 	{ .compatible = "qcom,msm-iommu-v1-ns" },
747 	{ .compatible = "qcom,msm-iommu-v1-sec" },
748 	{ .compatible = "qcom,msm-iommu-v2-ns" },
749 	{ .compatible = "qcom,msm-iommu-v2-sec" },
750 	{ /* sentinel */ }
751 };
752 
753 static struct platform_driver qcom_iommu_ctx_driver = {
754 	.driver	= {
755 		.name		= "qcom-iommu-ctx",
756 		.of_match_table	= ctx_of_match,
757 	},
758 	.probe	= qcom_iommu_ctx_probe,
759 	.remove = qcom_iommu_ctx_remove,
760 };
761 
qcom_iommu_has_secure_context(struct qcom_iommu_dev * qcom_iommu)762 static bool qcom_iommu_has_secure_context(struct qcom_iommu_dev *qcom_iommu)
763 {
764 	struct device_node *child;
765 
766 	for_each_child_of_node(qcom_iommu->dev->of_node, child) {
767 		if (of_device_is_compatible(child, "qcom,msm-iommu-v1-sec") ||
768 		    of_device_is_compatible(child, "qcom,msm-iommu-v2-sec")) {
769 			of_node_put(child);
770 			return true;
771 		}
772 	}
773 
774 	return false;
775 }
776 
qcom_iommu_device_probe(struct platform_device * pdev)777 static int qcom_iommu_device_probe(struct platform_device *pdev)
778 {
779 	struct device_node *child;
780 	struct qcom_iommu_dev *qcom_iommu;
781 	struct device *dev = &pdev->dev;
782 	struct resource *res;
783 	struct clk *clk;
784 	int ret, max_asid = 0;
785 
786 	/* find the max asid (which is 1:1 to ctx bank idx), so we know how
787 	 * many child ctx devices we have:
788 	 */
789 	for_each_child_of_node(dev->of_node, child)
790 		max_asid = max(max_asid, get_asid(child));
791 
792 	qcom_iommu = devm_kzalloc(dev, struct_size(qcom_iommu, ctxs, max_asid + 1),
793 				  GFP_KERNEL);
794 	if (!qcom_iommu)
795 		return -ENOMEM;
796 	qcom_iommu->max_asid = max_asid;
797 	qcom_iommu->dev = dev;
798 
799 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
800 	if (res) {
801 		qcom_iommu->local_base = devm_ioremap_resource(dev, res);
802 		if (IS_ERR(qcom_iommu->local_base))
803 			return PTR_ERR(qcom_iommu->local_base);
804 	}
805 
806 	clk = devm_clk_get(dev, "iface");
807 	if (IS_ERR(clk)) {
808 		dev_err(dev, "failed to get iface clock\n");
809 		return PTR_ERR(clk);
810 	}
811 	qcom_iommu->clks[CLK_IFACE].clk = clk;
812 
813 	clk = devm_clk_get(dev, "bus");
814 	if (IS_ERR(clk)) {
815 		dev_err(dev, "failed to get bus clock\n");
816 		return PTR_ERR(clk);
817 	}
818 	qcom_iommu->clks[CLK_BUS].clk = clk;
819 
820 	clk = devm_clk_get_optional(dev, "tbu");
821 	if (IS_ERR(clk)) {
822 		dev_err(dev, "failed to get tbu clock\n");
823 		return PTR_ERR(clk);
824 	}
825 	qcom_iommu->clks[CLK_TBU].clk = clk;
826 
827 	if (of_property_read_u32(dev->of_node, "qcom,iommu-secure-id",
828 				 &qcom_iommu->sec_id)) {
829 		dev_err(dev, "missing qcom,iommu-secure-id property\n");
830 		return -ENODEV;
831 	}
832 
833 	if (qcom_iommu_has_secure_context(qcom_iommu)) {
834 		ret = qcom_iommu_sec_ptbl_init(dev);
835 		if (ret) {
836 			dev_err(dev, "cannot init secure pg table(%d)\n", ret);
837 			return ret;
838 		}
839 	}
840 
841 	platform_set_drvdata(pdev, qcom_iommu);
842 
843 	pm_runtime_enable(dev);
844 
845 	/* register context bank devices, which are child nodes: */
846 	ret = devm_of_platform_populate(dev);
847 	if (ret) {
848 		dev_err(dev, "Failed to populate iommu contexts\n");
849 		goto err_pm_disable;
850 	}
851 
852 	ret = iommu_device_sysfs_add(&qcom_iommu->iommu, dev, NULL,
853 				     dev_name(dev));
854 	if (ret) {
855 		dev_err(dev, "Failed to register iommu in sysfs\n");
856 		goto err_pm_disable;
857 	}
858 
859 	ret = iommu_device_register(&qcom_iommu->iommu, &qcom_iommu_ops, dev);
860 	if (ret) {
861 		dev_err(dev, "Failed to register iommu\n");
862 		goto err_pm_disable;
863 	}
864 
865 	if (qcom_iommu->local_base) {
866 		pm_runtime_get_sync(dev);
867 		writel_relaxed(0xffffffff, qcom_iommu->local_base + SMMU_INTR_SEL_NS);
868 		pm_runtime_put_sync(dev);
869 	}
870 
871 	return 0;
872 
873 err_pm_disable:
874 	pm_runtime_disable(dev);
875 	return ret;
876 }
877 
qcom_iommu_device_remove(struct platform_device * pdev)878 static void qcom_iommu_device_remove(struct platform_device *pdev)
879 {
880 	struct qcom_iommu_dev *qcom_iommu = platform_get_drvdata(pdev);
881 
882 	pm_runtime_force_suspend(&pdev->dev);
883 	platform_set_drvdata(pdev, NULL);
884 	iommu_device_sysfs_remove(&qcom_iommu->iommu);
885 	iommu_device_unregister(&qcom_iommu->iommu);
886 }
887 
qcom_iommu_resume(struct device * dev)888 static int __maybe_unused qcom_iommu_resume(struct device *dev)
889 {
890 	struct qcom_iommu_dev *qcom_iommu = dev_get_drvdata(dev);
891 	int ret;
892 
893 	ret = clk_bulk_prepare_enable(CLK_NUM, qcom_iommu->clks);
894 	if (ret < 0)
895 		return ret;
896 
897 	if (dev->pm_domain)
898 		return qcom_scm_restore_sec_cfg(qcom_iommu->sec_id, 0);
899 
900 	return ret;
901 }
902 
qcom_iommu_suspend(struct device * dev)903 static int __maybe_unused qcom_iommu_suspend(struct device *dev)
904 {
905 	struct qcom_iommu_dev *qcom_iommu = dev_get_drvdata(dev);
906 
907 	clk_bulk_disable_unprepare(CLK_NUM, qcom_iommu->clks);
908 
909 	return 0;
910 }
911 
912 static const struct dev_pm_ops qcom_iommu_pm_ops = {
913 	SET_RUNTIME_PM_OPS(qcom_iommu_suspend, qcom_iommu_resume, NULL)
914 	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
915 				pm_runtime_force_resume)
916 };
917 
918 static const struct of_device_id qcom_iommu_of_match[] = {
919 	{ .compatible = "qcom,msm-iommu-v1" },
920 	{ .compatible = "qcom,msm-iommu-v2" },
921 	{ /* sentinel */ }
922 };
923 
924 static struct platform_driver qcom_iommu_driver = {
925 	.driver	= {
926 		.name		= "qcom-iommu",
927 		.of_match_table	= qcom_iommu_of_match,
928 		.pm		= &qcom_iommu_pm_ops,
929 	},
930 	.probe	= qcom_iommu_device_probe,
931 	.remove = qcom_iommu_device_remove,
932 };
933 
qcom_iommu_init(void)934 static int __init qcom_iommu_init(void)
935 {
936 	int ret;
937 
938 	ret = platform_driver_register(&qcom_iommu_ctx_driver);
939 	if (ret)
940 		return ret;
941 
942 	ret = platform_driver_register(&qcom_iommu_driver);
943 	if (ret)
944 		platform_driver_unregister(&qcom_iommu_ctx_driver);
945 
946 	return ret;
947 }
948 device_initcall(qcom_iommu_init);
949