Merge tag 'armsoc-dt' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
[sfrench/cifs-2.6.git] / drivers / iommu / ipmmu-vmsa.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * IOMMU API for Renesas VMSA-compatible IPMMU
4  * Author: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
5  *
6  * Copyright (C) 2014 Renesas Electronics Corporation
7  */
8
9 #include <linux/bitmap.h>
10 #include <linux/delay.h>
11 #include <linux/dma-iommu.h>
12 #include <linux/dma-mapping.h>
13 #include <linux/err.h>
14 #include <linux/export.h>
15 #include <linux/init.h>
16 #include <linux/interrupt.h>
17 #include <linux/io.h>
18 #include <linux/io-pgtable.h>
19 #include <linux/iommu.h>
20 #include <linux/of.h>
21 #include <linux/of_device.h>
22 #include <linux/of_iommu.h>
23 #include <linux/of_platform.h>
24 #include <linux/platform_device.h>
25 #include <linux/sizes.h>
26 #include <linux/slab.h>
27 #include <linux/sys_soc.h>
28
29 #if defined(CONFIG_ARM) && !defined(CONFIG_IOMMU_DMA)
30 #include <asm/dma-iommu.h>
31 #include <asm/pgalloc.h>
32 #else
33 #define arm_iommu_create_mapping(...)   NULL
34 #define arm_iommu_attach_device(...)    -ENODEV
35 #define arm_iommu_release_mapping(...)  do {} while (0)
36 #define arm_iommu_detach_device(...)    do {} while (0)
37 #endif
38
39 #define IPMMU_CTX_MAX           8U
40 #define IPMMU_CTX_INVALID       -1
41
42 #define IPMMU_UTLB_MAX          48U
43
44 struct ipmmu_features {
45         bool use_ns_alias_offset;
46         bool has_cache_leaf_nodes;
47         unsigned int number_of_contexts;
48         unsigned int num_utlbs;
49         bool setup_imbuscr;
50         bool twobit_imttbcr_sl0;
51         bool reserved_context;
52 };
53
54 struct ipmmu_vmsa_device {
55         struct device *dev;
56         void __iomem *base;
57         struct iommu_device iommu;
58         struct ipmmu_vmsa_device *root;
59         const struct ipmmu_features *features;
60         unsigned int num_ctx;
61         spinlock_t lock;                        /* Protects ctx and domains[] */
62         DECLARE_BITMAP(ctx, IPMMU_CTX_MAX);
63         struct ipmmu_vmsa_domain *domains[IPMMU_CTX_MAX];
64         s8 utlb_ctx[IPMMU_UTLB_MAX];
65
66         struct iommu_group *group;
67         struct dma_iommu_mapping *mapping;
68 };
69
70 struct ipmmu_vmsa_domain {
71         struct ipmmu_vmsa_device *mmu;
72         struct iommu_domain io_domain;
73
74         struct io_pgtable_cfg cfg;
75         struct io_pgtable_ops *iop;
76
77         unsigned int context_id;
78         struct mutex mutex;                     /* Protects mappings */
79 };
80
81 static struct ipmmu_vmsa_domain *to_vmsa_domain(struct iommu_domain *dom)
82 {
83         return container_of(dom, struct ipmmu_vmsa_domain, io_domain);
84 }
85
86 static struct ipmmu_vmsa_device *to_ipmmu(struct device *dev)
87 {
88         struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
89
90         return fwspec ? fwspec->iommu_priv : NULL;
91 }
92
93 #define TLB_LOOP_TIMEOUT                100     /* 100us */
94
95 /* -----------------------------------------------------------------------------
96  * Registers Definition
97  */
98
99 #define IM_NS_ALIAS_OFFSET              0x800
100
101 #define IM_CTX_SIZE                     0x40
102
103 #define IMCTR                           0x0000
104 #define IMCTR_TRE                       (1 << 17)
105 #define IMCTR_AFE                       (1 << 16)
106 #define IMCTR_RTSEL_MASK                (3 << 4)
107 #define IMCTR_RTSEL_SHIFT               4
108 #define IMCTR_TREN                      (1 << 3)
109 #define IMCTR_INTEN                     (1 << 2)
110 #define IMCTR_FLUSH                     (1 << 1)
111 #define IMCTR_MMUEN                     (1 << 0)
112
113 #define IMCAAR                          0x0004
114
115 #define IMTTBCR                         0x0008
116 #define IMTTBCR_EAE                     (1 << 31)
117 #define IMTTBCR_PMB                     (1 << 30)
118 #define IMTTBCR_SH1_NON_SHAREABLE       (0 << 28)
119 #define IMTTBCR_SH1_OUTER_SHAREABLE     (2 << 28)
120 #define IMTTBCR_SH1_INNER_SHAREABLE     (3 << 28)
121 #define IMTTBCR_SH1_MASK                (3 << 28)
122 #define IMTTBCR_ORGN1_NC                (0 << 26)
123 #define IMTTBCR_ORGN1_WB_WA             (1 << 26)
124 #define IMTTBCR_ORGN1_WT                (2 << 26)
125 #define IMTTBCR_ORGN1_WB                (3 << 26)
126 #define IMTTBCR_ORGN1_MASK              (3 << 26)
127 #define IMTTBCR_IRGN1_NC                (0 << 24)
128 #define IMTTBCR_IRGN1_WB_WA             (1 << 24)
129 #define IMTTBCR_IRGN1_WT                (2 << 24)
130 #define IMTTBCR_IRGN1_WB                (3 << 24)
131 #define IMTTBCR_IRGN1_MASK              (3 << 24)
132 #define IMTTBCR_TSZ1_MASK               (7 << 16)
133 #define IMTTBCR_TSZ1_SHIFT              16
134 #define IMTTBCR_SH0_NON_SHAREABLE       (0 << 12)
135 #define IMTTBCR_SH0_OUTER_SHAREABLE     (2 << 12)
136 #define IMTTBCR_SH0_INNER_SHAREABLE     (3 << 12)
137 #define IMTTBCR_SH0_MASK                (3 << 12)
138 #define IMTTBCR_ORGN0_NC                (0 << 10)
139 #define IMTTBCR_ORGN0_WB_WA             (1 << 10)
140 #define IMTTBCR_ORGN0_WT                (2 << 10)
141 #define IMTTBCR_ORGN0_WB                (3 << 10)
142 #define IMTTBCR_ORGN0_MASK              (3 << 10)
143 #define IMTTBCR_IRGN0_NC                (0 << 8)
144 #define IMTTBCR_IRGN0_WB_WA             (1 << 8)
145 #define IMTTBCR_IRGN0_WT                (2 << 8)
146 #define IMTTBCR_IRGN0_WB                (3 << 8)
147 #define IMTTBCR_IRGN0_MASK              (3 << 8)
148 #define IMTTBCR_SL0_LVL_2               (0 << 4)
149 #define IMTTBCR_SL0_LVL_1               (1 << 4)
150 #define IMTTBCR_TSZ0_MASK               (7 << 0)
151 #define IMTTBCR_TSZ0_SHIFT              O
152
153 #define IMTTBCR_SL0_TWOBIT_LVL_3        (0 << 6)
154 #define IMTTBCR_SL0_TWOBIT_LVL_2        (1 << 6)
155 #define IMTTBCR_SL0_TWOBIT_LVL_1        (2 << 6)
156
157 #define IMBUSCR                         0x000c
158 #define IMBUSCR_DVM                     (1 << 2)
159 #define IMBUSCR_BUSSEL_SYS              (0 << 0)
160 #define IMBUSCR_BUSSEL_CCI              (1 << 0)
161 #define IMBUSCR_BUSSEL_IMCAAR           (2 << 0)
162 #define IMBUSCR_BUSSEL_CCI_IMCAAR       (3 << 0)
163 #define IMBUSCR_BUSSEL_MASK             (3 << 0)
164
165 #define IMTTLBR0                        0x0010
166 #define IMTTUBR0                        0x0014
167 #define IMTTLBR1                        0x0018
168 #define IMTTUBR1                        0x001c
169
170 #define IMSTR                           0x0020
171 #define IMSTR_ERRLVL_MASK               (3 << 12)
172 #define IMSTR_ERRLVL_SHIFT              12
173 #define IMSTR_ERRCODE_TLB_FORMAT        (1 << 8)
174 #define IMSTR_ERRCODE_ACCESS_PERM       (4 << 8)
175 #define IMSTR_ERRCODE_SECURE_ACCESS     (5 << 8)
176 #define IMSTR_ERRCODE_MASK              (7 << 8)
177 #define IMSTR_MHIT                      (1 << 4)
178 #define IMSTR_ABORT                     (1 << 2)
179 #define IMSTR_PF                        (1 << 1)
180 #define IMSTR_TF                        (1 << 0)
181
182 #define IMMAIR0                         0x0028
183 #define IMMAIR1                         0x002c
184 #define IMMAIR_ATTR_MASK                0xff
185 #define IMMAIR_ATTR_DEVICE              0x04
186 #define IMMAIR_ATTR_NC                  0x44
187 #define IMMAIR_ATTR_WBRWA               0xff
188 #define IMMAIR_ATTR_SHIFT(n)            ((n) << 3)
189 #define IMMAIR_ATTR_IDX_NC              0
190 #define IMMAIR_ATTR_IDX_WBRWA           1
191 #define IMMAIR_ATTR_IDX_DEV             2
192
193 #define IMELAR                          0x0030  /* IMEAR on R-Car Gen2 */
194 #define IMEUAR                          0x0034  /* R-Car Gen3 only */
195
196 #define IMPCTR                          0x0200
197 #define IMPSTR                          0x0208
198 #define IMPEAR                          0x020c
199 #define IMPMBA(n)                       (0x0280 + ((n) * 4))
200 #define IMPMBD(n)                       (0x02c0 + ((n) * 4))
201
202 #define IMUCTR(n)                       ((n) < 32 ? IMUCTR0(n) : IMUCTR32(n))
203 #define IMUCTR0(n)                      (0x0300 + ((n) * 16))
204 #define IMUCTR32(n)                     (0x0600 + (((n) - 32) * 16))
205 #define IMUCTR_FIXADDEN                 (1 << 31)
206 #define IMUCTR_FIXADD_MASK              (0xff << 16)
207 #define IMUCTR_FIXADD_SHIFT             16
208 #define IMUCTR_TTSEL_MMU(n)             ((n) << 4)
209 #define IMUCTR_TTSEL_PMB                (8 << 4)
210 #define IMUCTR_TTSEL_MASK               (15 << 4)
211 #define IMUCTR_FLUSH                    (1 << 1)
212 #define IMUCTR_MMUEN                    (1 << 0)
213
214 #define IMUASID(n)                      ((n) < 32 ? IMUASID0(n) : IMUASID32(n))
215 #define IMUASID0(n)                     (0x0308 + ((n) * 16))
216 #define IMUASID32(n)                    (0x0608 + (((n) - 32) * 16))
217 #define IMUASID_ASID8_MASK              (0xff << 8)
218 #define IMUASID_ASID8_SHIFT             8
219 #define IMUASID_ASID0_MASK              (0xff << 0)
220 #define IMUASID_ASID0_SHIFT             0
221
222 /* -----------------------------------------------------------------------------
223  * Root device handling
224  */
225
226 static struct platform_driver ipmmu_driver;
227
228 static bool ipmmu_is_root(struct ipmmu_vmsa_device *mmu)
229 {
230         return mmu->root == mmu;
231 }
232
233 static int __ipmmu_check_device(struct device *dev, void *data)
234 {
235         struct ipmmu_vmsa_device *mmu = dev_get_drvdata(dev);
236         struct ipmmu_vmsa_device **rootp = data;
237
238         if (ipmmu_is_root(mmu))
239                 *rootp = mmu;
240
241         return 0;
242 }
243
244 static struct ipmmu_vmsa_device *ipmmu_find_root(void)
245 {
246         struct ipmmu_vmsa_device *root = NULL;
247
248         return driver_for_each_device(&ipmmu_driver.driver, NULL, &root,
249                                       __ipmmu_check_device) == 0 ? root : NULL;
250 }
251
252 /* -----------------------------------------------------------------------------
253  * Read/Write Access
254  */
255
256 static u32 ipmmu_read(struct ipmmu_vmsa_device *mmu, unsigned int offset)
257 {
258         return ioread32(mmu->base + offset);
259 }
260
261 static void ipmmu_write(struct ipmmu_vmsa_device *mmu, unsigned int offset,
262                         u32 data)
263 {
264         iowrite32(data, mmu->base + offset);
265 }
266
267 static u32 ipmmu_ctx_read_root(struct ipmmu_vmsa_domain *domain,
268                                unsigned int reg)
269 {
270         return ipmmu_read(domain->mmu->root,
271                           domain->context_id * IM_CTX_SIZE + reg);
272 }
273
274 static void ipmmu_ctx_write_root(struct ipmmu_vmsa_domain *domain,
275                                  unsigned int reg, u32 data)
276 {
277         ipmmu_write(domain->mmu->root,
278                     domain->context_id * IM_CTX_SIZE + reg, data);
279 }
280
281 static void ipmmu_ctx_write_all(struct ipmmu_vmsa_domain *domain,
282                                 unsigned int reg, u32 data)
283 {
284         if (domain->mmu != domain->mmu->root)
285                 ipmmu_write(domain->mmu,
286                             domain->context_id * IM_CTX_SIZE + reg, data);
287
288         ipmmu_write(domain->mmu->root,
289                     domain->context_id * IM_CTX_SIZE + reg, data);
290 }
291
292 /* -----------------------------------------------------------------------------
293  * TLB and microTLB Management
294  */
295
296 /* Wait for any pending TLB invalidations to complete */
297 static void ipmmu_tlb_sync(struct ipmmu_vmsa_domain *domain)
298 {
299         unsigned int count = 0;
300
301         while (ipmmu_ctx_read_root(domain, IMCTR) & IMCTR_FLUSH) {
302                 cpu_relax();
303                 if (++count == TLB_LOOP_TIMEOUT) {
304                         dev_err_ratelimited(domain->mmu->dev,
305                         "TLB sync timed out -- MMU may be deadlocked\n");
306                         return;
307                 }
308                 udelay(1);
309         }
310 }
311
312 static void ipmmu_tlb_invalidate(struct ipmmu_vmsa_domain *domain)
313 {
314         u32 reg;
315
316         reg = ipmmu_ctx_read_root(domain, IMCTR);
317         reg |= IMCTR_FLUSH;
318         ipmmu_ctx_write_all(domain, IMCTR, reg);
319
320         ipmmu_tlb_sync(domain);
321 }
322
323 /*
324  * Enable MMU translation for the microTLB.
325  */
326 static void ipmmu_utlb_enable(struct ipmmu_vmsa_domain *domain,
327                               unsigned int utlb)
328 {
329         struct ipmmu_vmsa_device *mmu = domain->mmu;
330
331         /*
332          * TODO: Reference-count the microTLB as several bus masters can be
333          * connected to the same microTLB.
334          */
335
336         /* TODO: What should we set the ASID to ? */
337         ipmmu_write(mmu, IMUASID(utlb), 0);
338         /* TODO: Do we need to flush the microTLB ? */
339         ipmmu_write(mmu, IMUCTR(utlb),
340                     IMUCTR_TTSEL_MMU(domain->context_id) | IMUCTR_FLUSH |
341                     IMUCTR_MMUEN);
342         mmu->utlb_ctx[utlb] = domain->context_id;
343 }
344
345 /*
346  * Disable MMU translation for the microTLB.
347  */
348 static void ipmmu_utlb_disable(struct ipmmu_vmsa_domain *domain,
349                                unsigned int utlb)
350 {
351         struct ipmmu_vmsa_device *mmu = domain->mmu;
352
353         ipmmu_write(mmu, IMUCTR(utlb), 0);
354         mmu->utlb_ctx[utlb] = IPMMU_CTX_INVALID;
355 }
356
357 static void ipmmu_tlb_flush_all(void *cookie)
358 {
359         struct ipmmu_vmsa_domain *domain = cookie;
360
361         ipmmu_tlb_invalidate(domain);
362 }
363
364 static void ipmmu_tlb_add_flush(unsigned long iova, size_t size,
365                                 size_t granule, bool leaf, void *cookie)
366 {
367         /* The hardware doesn't support selective TLB flush. */
368 }
369
370 static const struct iommu_gather_ops ipmmu_gather_ops = {
371         .tlb_flush_all = ipmmu_tlb_flush_all,
372         .tlb_add_flush = ipmmu_tlb_add_flush,
373         .tlb_sync = ipmmu_tlb_flush_all,
374 };
375
376 /* -----------------------------------------------------------------------------
377  * Domain/Context Management
378  */
379
380 static int ipmmu_domain_allocate_context(struct ipmmu_vmsa_device *mmu,
381                                          struct ipmmu_vmsa_domain *domain)
382 {
383         unsigned long flags;
384         int ret;
385
386         spin_lock_irqsave(&mmu->lock, flags);
387
388         ret = find_first_zero_bit(mmu->ctx, mmu->num_ctx);
389         if (ret != mmu->num_ctx) {
390                 mmu->domains[ret] = domain;
391                 set_bit(ret, mmu->ctx);
392         } else
393                 ret = -EBUSY;
394
395         spin_unlock_irqrestore(&mmu->lock, flags);
396
397         return ret;
398 }
399
400 static void ipmmu_domain_free_context(struct ipmmu_vmsa_device *mmu,
401                                       unsigned int context_id)
402 {
403         unsigned long flags;
404
405         spin_lock_irqsave(&mmu->lock, flags);
406
407         clear_bit(context_id, mmu->ctx);
408         mmu->domains[context_id] = NULL;
409
410         spin_unlock_irqrestore(&mmu->lock, flags);
411 }
412
413 static void ipmmu_domain_setup_context(struct ipmmu_vmsa_domain *domain)
414 {
415         u64 ttbr;
416         u32 tmp;
417
418         /* TTBR0 */
419         ttbr = domain->cfg.arm_lpae_s1_cfg.ttbr[0];
420         ipmmu_ctx_write_root(domain, IMTTLBR0, ttbr);
421         ipmmu_ctx_write_root(domain, IMTTUBR0, ttbr >> 32);
422
423         /*
424          * TTBCR
425          * We use long descriptors with inner-shareable WBWA tables and allocate
426          * the whole 32-bit VA space to TTBR0.
427          */
428         if (domain->mmu->features->twobit_imttbcr_sl0)
429                 tmp = IMTTBCR_SL0_TWOBIT_LVL_1;
430         else
431                 tmp = IMTTBCR_SL0_LVL_1;
432
433         ipmmu_ctx_write_root(domain, IMTTBCR, IMTTBCR_EAE |
434                              IMTTBCR_SH0_INNER_SHAREABLE | IMTTBCR_ORGN0_WB_WA |
435                              IMTTBCR_IRGN0_WB_WA | tmp);
436
437         /* MAIR0 */
438         ipmmu_ctx_write_root(domain, IMMAIR0,
439                              domain->cfg.arm_lpae_s1_cfg.mair[0]);
440
441         /* IMBUSCR */
442         if (domain->mmu->features->setup_imbuscr)
443                 ipmmu_ctx_write_root(domain, IMBUSCR,
444                                      ipmmu_ctx_read_root(domain, IMBUSCR) &
445                                      ~(IMBUSCR_DVM | IMBUSCR_BUSSEL_MASK));
446
447         /*
448          * IMSTR
449          * Clear all interrupt flags.
450          */
451         ipmmu_ctx_write_root(domain, IMSTR, ipmmu_ctx_read_root(domain, IMSTR));
452
453         /*
454          * IMCTR
455          * Enable the MMU and interrupt generation. The long-descriptor
456          * translation table format doesn't use TEX remapping. Don't enable AF
457          * software management as we have no use for it. Flush the TLB as
458          * required when modifying the context registers.
459          */
460         ipmmu_ctx_write_all(domain, IMCTR,
461                             IMCTR_INTEN | IMCTR_FLUSH | IMCTR_MMUEN);
462 }
463
464 static int ipmmu_domain_init_context(struct ipmmu_vmsa_domain *domain)
465 {
466         int ret;
467
468         /*
469          * Allocate the page table operations.
470          *
471          * VMSA states in section B3.6.3 "Control of Secure or Non-secure memory
472          * access, Long-descriptor format" that the NStable bit being set in a
473          * table descriptor will result in the NStable and NS bits of all child
474          * entries being ignored and considered as being set. The IPMMU seems
475          * not to comply with this, as it generates a secure access page fault
476          * if any of the NStable and NS bits isn't set when running in
477          * non-secure mode.
478          */
479         domain->cfg.quirks = IO_PGTABLE_QUIRK_ARM_NS;
480         domain->cfg.pgsize_bitmap = SZ_1G | SZ_2M | SZ_4K;
481         domain->cfg.ias = 32;
482         domain->cfg.oas = 40;
483         domain->cfg.tlb = &ipmmu_gather_ops;
484         domain->io_domain.geometry.aperture_end = DMA_BIT_MASK(32);
485         domain->io_domain.geometry.force_aperture = true;
486         /*
487          * TODO: Add support for coherent walk through CCI with DVM and remove
488          * cache handling. For now, delegate it to the io-pgtable code.
489          */
490         domain->cfg.coherent_walk = false;
491         domain->cfg.iommu_dev = domain->mmu->root->dev;
492
493         /*
494          * Find an unused context.
495          */
496         ret = ipmmu_domain_allocate_context(domain->mmu->root, domain);
497         if (ret < 0)
498                 return ret;
499
500         domain->context_id = ret;
501
502         domain->iop = alloc_io_pgtable_ops(ARM_32_LPAE_S1, &domain->cfg,
503                                            domain);
504         if (!domain->iop) {
505                 ipmmu_domain_free_context(domain->mmu->root,
506                                           domain->context_id);
507                 return -EINVAL;
508         }
509
510         ipmmu_domain_setup_context(domain);
511         return 0;
512 }
513
514 static void ipmmu_domain_destroy_context(struct ipmmu_vmsa_domain *domain)
515 {
516         if (!domain->mmu)
517                 return;
518
519         /*
520          * Disable the context. Flush the TLB as required when modifying the
521          * context registers.
522          *
523          * TODO: Is TLB flush really needed ?
524          */
525         ipmmu_ctx_write_all(domain, IMCTR, IMCTR_FLUSH);
526         ipmmu_tlb_sync(domain);
527         ipmmu_domain_free_context(domain->mmu->root, domain->context_id);
528 }
529
530 /* -----------------------------------------------------------------------------
531  * Fault Handling
532  */
533
534 static irqreturn_t ipmmu_domain_irq(struct ipmmu_vmsa_domain *domain)
535 {
536         const u32 err_mask = IMSTR_MHIT | IMSTR_ABORT | IMSTR_PF | IMSTR_TF;
537         struct ipmmu_vmsa_device *mmu = domain->mmu;
538         unsigned long iova;
539         u32 status;
540
541         status = ipmmu_ctx_read_root(domain, IMSTR);
542         if (!(status & err_mask))
543                 return IRQ_NONE;
544
545         iova = ipmmu_ctx_read_root(domain, IMELAR);
546         if (IS_ENABLED(CONFIG_64BIT))
547                 iova |= (u64)ipmmu_ctx_read_root(domain, IMEUAR) << 32;
548
549         /*
550          * Clear the error status flags. Unlike traditional interrupt flag
551          * registers that must be cleared by writing 1, this status register
552          * seems to require 0. The error address register must be read before,
553          * otherwise its value will be 0.
554          */
555         ipmmu_ctx_write_root(domain, IMSTR, 0);
556
557         /* Log fatal errors. */
558         if (status & IMSTR_MHIT)
559                 dev_err_ratelimited(mmu->dev, "Multiple TLB hits @0x%lx\n",
560                                     iova);
561         if (status & IMSTR_ABORT)
562                 dev_err_ratelimited(mmu->dev, "Page Table Walk Abort @0x%lx\n",
563                                     iova);
564
565         if (!(status & (IMSTR_PF | IMSTR_TF)))
566                 return IRQ_NONE;
567
568         /*
569          * Try to handle page faults and translation faults.
570          *
571          * TODO: We need to look up the faulty device based on the I/O VA. Use
572          * the IOMMU device for now.
573          */
574         if (!report_iommu_fault(&domain->io_domain, mmu->dev, iova, 0))
575                 return IRQ_HANDLED;
576
577         dev_err_ratelimited(mmu->dev,
578                             "Unhandled fault: status 0x%08x iova 0x%lx\n",
579                             status, iova);
580
581         return IRQ_HANDLED;
582 }
583
584 static irqreturn_t ipmmu_irq(int irq, void *dev)
585 {
586         struct ipmmu_vmsa_device *mmu = dev;
587         irqreturn_t status = IRQ_NONE;
588         unsigned int i;
589         unsigned long flags;
590
591         spin_lock_irqsave(&mmu->lock, flags);
592
593         /*
594          * Check interrupts for all active contexts.
595          */
596         for (i = 0; i < mmu->num_ctx; i++) {
597                 if (!mmu->domains[i])
598                         continue;
599                 if (ipmmu_domain_irq(mmu->domains[i]) == IRQ_HANDLED)
600                         status = IRQ_HANDLED;
601         }
602
603         spin_unlock_irqrestore(&mmu->lock, flags);
604
605         return status;
606 }
607
608 /* -----------------------------------------------------------------------------
609  * IOMMU Operations
610  */
611
612 static struct iommu_domain *__ipmmu_domain_alloc(unsigned type)
613 {
614         struct ipmmu_vmsa_domain *domain;
615
616         domain = kzalloc(sizeof(*domain), GFP_KERNEL);
617         if (!domain)
618                 return NULL;
619
620         mutex_init(&domain->mutex);
621
622         return &domain->io_domain;
623 }
624
625 static struct iommu_domain *ipmmu_domain_alloc(unsigned type)
626 {
627         struct iommu_domain *io_domain = NULL;
628
629         switch (type) {
630         case IOMMU_DOMAIN_UNMANAGED:
631                 io_domain = __ipmmu_domain_alloc(type);
632                 break;
633
634         case IOMMU_DOMAIN_DMA:
635                 io_domain = __ipmmu_domain_alloc(type);
636                 if (io_domain && iommu_get_dma_cookie(io_domain)) {
637                         kfree(io_domain);
638                         io_domain = NULL;
639                 }
640                 break;
641         }
642
643         return io_domain;
644 }
645
646 static void ipmmu_domain_free(struct iommu_domain *io_domain)
647 {
648         struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
649
650         /*
651          * Free the domain resources. We assume that all devices have already
652          * been detached.
653          */
654         iommu_put_dma_cookie(io_domain);
655         ipmmu_domain_destroy_context(domain);
656         free_io_pgtable_ops(domain->iop);
657         kfree(domain);
658 }
659
660 static int ipmmu_attach_device(struct iommu_domain *io_domain,
661                                struct device *dev)
662 {
663         struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
664         struct ipmmu_vmsa_device *mmu = to_ipmmu(dev);
665         struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
666         unsigned int i;
667         int ret = 0;
668
669         if (!mmu) {
670                 dev_err(dev, "Cannot attach to IPMMU\n");
671                 return -ENXIO;
672         }
673
674         mutex_lock(&domain->mutex);
675
676         if (!domain->mmu) {
677                 /* The domain hasn't been used yet, initialize it. */
678                 domain->mmu = mmu;
679                 ret = ipmmu_domain_init_context(domain);
680                 if (ret < 0) {
681                         dev_err(dev, "Unable to initialize IPMMU context\n");
682                         domain->mmu = NULL;
683                 } else {
684                         dev_info(dev, "Using IPMMU context %u\n",
685                                  domain->context_id);
686                 }
687         } else if (domain->mmu != mmu) {
688                 /*
689                  * Something is wrong, we can't attach two devices using
690                  * different IOMMUs to the same domain.
691                  */
692                 dev_err(dev, "Can't attach IPMMU %s to domain on IPMMU %s\n",
693                         dev_name(mmu->dev), dev_name(domain->mmu->dev));
694                 ret = -EINVAL;
695         } else
696                 dev_info(dev, "Reusing IPMMU context %u\n", domain->context_id);
697
698         mutex_unlock(&domain->mutex);
699
700         if (ret < 0)
701                 return ret;
702
703         for (i = 0; i < fwspec->num_ids; ++i)
704                 ipmmu_utlb_enable(domain, fwspec->ids[i]);
705
706         return 0;
707 }
708
709 static void ipmmu_detach_device(struct iommu_domain *io_domain,
710                                 struct device *dev)
711 {
712         struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
713         struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
714         unsigned int i;
715
716         for (i = 0; i < fwspec->num_ids; ++i)
717                 ipmmu_utlb_disable(domain, fwspec->ids[i]);
718
719         /*
720          * TODO: Optimize by disabling the context when no device is attached.
721          */
722 }
723
724 static int ipmmu_map(struct iommu_domain *io_domain, unsigned long iova,
725                      phys_addr_t paddr, size_t size, int prot)
726 {
727         struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
728
729         if (!domain)
730                 return -ENODEV;
731
732         return domain->iop->map(domain->iop, iova, paddr, size, prot);
733 }
734
735 static size_t ipmmu_unmap(struct iommu_domain *io_domain, unsigned long iova,
736                           size_t size)
737 {
738         struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
739
740         return domain->iop->unmap(domain->iop, iova, size);
741 }
742
743 static void ipmmu_iotlb_sync(struct iommu_domain *io_domain)
744 {
745         struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
746
747         if (domain->mmu)
748                 ipmmu_tlb_flush_all(domain);
749 }
750
751 static phys_addr_t ipmmu_iova_to_phys(struct iommu_domain *io_domain,
752                                       dma_addr_t iova)
753 {
754         struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
755
756         /* TODO: Is locking needed ? */
757
758         return domain->iop->iova_to_phys(domain->iop, iova);
759 }
760
761 static int ipmmu_init_platform_device(struct device *dev,
762                                       struct of_phandle_args *args)
763 {
764         struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
765         struct platform_device *ipmmu_pdev;
766
767         ipmmu_pdev = of_find_device_by_node(args->np);
768         if (!ipmmu_pdev)
769                 return -ENODEV;
770
771         fwspec->iommu_priv = platform_get_drvdata(ipmmu_pdev);
772
773         return 0;
774 }
775
776 static const struct soc_device_attribute soc_rcar_gen3[] = {
777         { .soc_id = "r8a774a1", },
778         { .soc_id = "r8a774c0", },
779         { .soc_id = "r8a7795", },
780         { .soc_id = "r8a7796", },
781         { .soc_id = "r8a77965", },
782         { .soc_id = "r8a77970", },
783         { .soc_id = "r8a77990", },
784         { .soc_id = "r8a77995", },
785         { /* sentinel */ }
786 };
787
788 static const struct soc_device_attribute soc_rcar_gen3_whitelist[] = {
789         { .soc_id = "r8a774c0", },
790         { .soc_id = "r8a7795", .revision = "ES3.*" },
791         { .soc_id = "r8a77965", },
792         { .soc_id = "r8a77990", },
793         { .soc_id = "r8a77995", },
794         { /* sentinel */ }
795 };
796
797 static const char * const rcar_gen3_slave_whitelist[] = {
798 };
799
800 static bool ipmmu_slave_whitelist(struct device *dev)
801 {
802         unsigned int i;
803
804         /*
805          * For R-Car Gen3 use a white list to opt-in slave devices.
806          * For Other SoCs, this returns true anyway.
807          */
808         if (!soc_device_match(soc_rcar_gen3))
809                 return true;
810
811         /* Check whether this R-Car Gen3 can use the IPMMU correctly or not */
812         if (!soc_device_match(soc_rcar_gen3_whitelist))
813                 return false;
814
815         /* Check whether this slave device can work with the IPMMU */
816         for (i = 0; i < ARRAY_SIZE(rcar_gen3_slave_whitelist); i++) {
817                 if (!strcmp(dev_name(dev), rcar_gen3_slave_whitelist[i]))
818                         return true;
819         }
820
821         /* Otherwise, do not allow use of IPMMU */
822         return false;
823 }
824
825 static int ipmmu_of_xlate(struct device *dev,
826                           struct of_phandle_args *spec)
827 {
828         if (!ipmmu_slave_whitelist(dev))
829                 return -ENODEV;
830
831         iommu_fwspec_add_ids(dev, spec->args, 1);
832
833         /* Initialize once - xlate() will call multiple times */
834         if (to_ipmmu(dev))
835                 return 0;
836
837         return ipmmu_init_platform_device(dev, spec);
838 }
839
840 static int ipmmu_init_arm_mapping(struct device *dev)
841 {
842         struct ipmmu_vmsa_device *mmu = to_ipmmu(dev);
843         struct iommu_group *group;
844         int ret;
845
846         /* Create a device group and add the device to it. */
847         group = iommu_group_alloc();
848         if (IS_ERR(group)) {
849                 dev_err(dev, "Failed to allocate IOMMU group\n");
850                 return PTR_ERR(group);
851         }
852
853         ret = iommu_group_add_device(group, dev);
854         iommu_group_put(group);
855
856         if (ret < 0) {
857                 dev_err(dev, "Failed to add device to IPMMU group\n");
858                 return ret;
859         }
860
861         /*
862          * Create the ARM mapping, used by the ARM DMA mapping core to allocate
863          * VAs. This will allocate a corresponding IOMMU domain.
864          *
865          * TODO:
866          * - Create one mapping per context (TLB).
867          * - Make the mapping size configurable ? We currently use a 2GB mapping
868          *   at a 1GB offset to ensure that NULL VAs will fault.
869          */
870         if (!mmu->mapping) {
871                 struct dma_iommu_mapping *mapping;
872
873                 mapping = arm_iommu_create_mapping(&platform_bus_type,
874                                                    SZ_1G, SZ_2G);
875                 if (IS_ERR(mapping)) {
876                         dev_err(mmu->dev, "failed to create ARM IOMMU mapping\n");
877                         ret = PTR_ERR(mapping);
878                         goto error;
879                 }
880
881                 mmu->mapping = mapping;
882         }
883
884         /* Attach the ARM VA mapping to the device. */
885         ret = arm_iommu_attach_device(dev, mmu->mapping);
886         if (ret < 0) {
887                 dev_err(dev, "Failed to attach device to VA mapping\n");
888                 goto error;
889         }
890
891         return 0;
892
893 error:
894         iommu_group_remove_device(dev);
895         if (mmu->mapping)
896                 arm_iommu_release_mapping(mmu->mapping);
897
898         return ret;
899 }
900
901 static int ipmmu_add_device(struct device *dev)
902 {
903         struct ipmmu_vmsa_device *mmu = to_ipmmu(dev);
904         struct iommu_group *group;
905         int ret;
906
907         /*
908          * Only let through devices that have been verified in xlate()
909          */
910         if (!mmu)
911                 return -ENODEV;
912
913         if (IS_ENABLED(CONFIG_ARM) && !IS_ENABLED(CONFIG_IOMMU_DMA)) {
914                 ret = ipmmu_init_arm_mapping(dev);
915                 if (ret)
916                         return ret;
917         } else {
918                 group = iommu_group_get_for_dev(dev);
919                 if (IS_ERR(group))
920                         return PTR_ERR(group);
921
922                 iommu_group_put(group);
923         }
924
925         iommu_device_link(&mmu->iommu, dev);
926         return 0;
927 }
928
929 static void ipmmu_remove_device(struct device *dev)
930 {
931         struct ipmmu_vmsa_device *mmu = to_ipmmu(dev);
932
933         iommu_device_unlink(&mmu->iommu, dev);
934         arm_iommu_detach_device(dev);
935         iommu_group_remove_device(dev);
936 }
937
938 static struct iommu_group *ipmmu_find_group(struct device *dev)
939 {
940         struct ipmmu_vmsa_device *mmu = to_ipmmu(dev);
941         struct iommu_group *group;
942
943         if (mmu->group)
944                 return iommu_group_ref_get(mmu->group);
945
946         group = iommu_group_alloc();
947         if (!IS_ERR(group))
948                 mmu->group = group;
949
950         return group;
951 }
952
953 static const struct iommu_ops ipmmu_ops = {
954         .domain_alloc = ipmmu_domain_alloc,
955         .domain_free = ipmmu_domain_free,
956         .attach_dev = ipmmu_attach_device,
957         .detach_dev = ipmmu_detach_device,
958         .map = ipmmu_map,
959         .unmap = ipmmu_unmap,
960         .flush_iotlb_all = ipmmu_iotlb_sync,
961         .iotlb_sync = ipmmu_iotlb_sync,
962         .iova_to_phys = ipmmu_iova_to_phys,
963         .add_device = ipmmu_add_device,
964         .remove_device = ipmmu_remove_device,
965         .device_group = ipmmu_find_group,
966         .pgsize_bitmap = SZ_1G | SZ_2M | SZ_4K,
967         .of_xlate = ipmmu_of_xlate,
968 };
969
970 /* -----------------------------------------------------------------------------
971  * Probe/remove and init
972  */
973
974 static void ipmmu_device_reset(struct ipmmu_vmsa_device *mmu)
975 {
976         unsigned int i;
977
978         /* Disable all contexts. */
979         for (i = 0; i < mmu->num_ctx; ++i)
980                 ipmmu_write(mmu, i * IM_CTX_SIZE + IMCTR, 0);
981 }
982
983 static const struct ipmmu_features ipmmu_features_default = {
984         .use_ns_alias_offset = true,
985         .has_cache_leaf_nodes = false,
986         .number_of_contexts = 1, /* software only tested with one context */
987         .num_utlbs = 32,
988         .setup_imbuscr = true,
989         .twobit_imttbcr_sl0 = false,
990         .reserved_context = false,
991 };
992
993 static const struct ipmmu_features ipmmu_features_rcar_gen3 = {
994         .use_ns_alias_offset = false,
995         .has_cache_leaf_nodes = true,
996         .number_of_contexts = 8,
997         .num_utlbs = 48,
998         .setup_imbuscr = false,
999         .twobit_imttbcr_sl0 = true,
1000         .reserved_context = true,
1001 };
1002
1003 static const struct of_device_id ipmmu_of_ids[] = {
1004         {
1005                 .compatible = "renesas,ipmmu-vmsa",
1006                 .data = &ipmmu_features_default,
1007         }, {
1008                 .compatible = "renesas,ipmmu-r8a774a1",
1009                 .data = &ipmmu_features_rcar_gen3,
1010         }, {
1011                 .compatible = "renesas,ipmmu-r8a774c0",
1012                 .data = &ipmmu_features_rcar_gen3,
1013         }, {
1014                 .compatible = "renesas,ipmmu-r8a7795",
1015                 .data = &ipmmu_features_rcar_gen3,
1016         }, {
1017                 .compatible = "renesas,ipmmu-r8a7796",
1018                 .data = &ipmmu_features_rcar_gen3,
1019         }, {
1020                 .compatible = "renesas,ipmmu-r8a77965",
1021                 .data = &ipmmu_features_rcar_gen3,
1022         }, {
1023                 .compatible = "renesas,ipmmu-r8a77970",
1024                 .data = &ipmmu_features_rcar_gen3,
1025         }, {
1026                 .compatible = "renesas,ipmmu-r8a77990",
1027                 .data = &ipmmu_features_rcar_gen3,
1028         }, {
1029                 .compatible = "renesas,ipmmu-r8a77995",
1030                 .data = &ipmmu_features_rcar_gen3,
1031         }, {
1032                 /* Terminator */
1033         },
1034 };
1035
1036 static int ipmmu_probe(struct platform_device *pdev)
1037 {
1038         struct ipmmu_vmsa_device *mmu;
1039         struct resource *res;
1040         int irq;
1041         int ret;
1042
1043         mmu = devm_kzalloc(&pdev->dev, sizeof(*mmu), GFP_KERNEL);
1044         if (!mmu) {
1045                 dev_err(&pdev->dev, "cannot allocate device data\n");
1046                 return -ENOMEM;
1047         }
1048
1049         mmu->dev = &pdev->dev;
1050         spin_lock_init(&mmu->lock);
1051         bitmap_zero(mmu->ctx, IPMMU_CTX_MAX);
1052         mmu->features = of_device_get_match_data(&pdev->dev);
1053         memset(mmu->utlb_ctx, IPMMU_CTX_INVALID, mmu->features->num_utlbs);
1054         dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(40));
1055
1056         /* Map I/O memory and request IRQ. */
1057         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1058         mmu->base = devm_ioremap_resource(&pdev->dev, res);
1059         if (IS_ERR(mmu->base))
1060                 return PTR_ERR(mmu->base);
1061
1062         /*
1063          * The IPMMU has two register banks, for secure and non-secure modes.
1064          * The bank mapped at the beginning of the IPMMU address space
1065          * corresponds to the running mode of the CPU. When running in secure
1066          * mode the non-secure register bank is also available at an offset.
1067          *
1068          * Secure mode operation isn't clearly documented and is thus currently
1069          * not implemented in the driver. Furthermore, preliminary tests of
1070          * non-secure operation with the main register bank were not successful.
1071          * Offset the registers base unconditionally to point to the non-secure
1072          * alias space for now.
1073          */
1074         if (mmu->features->use_ns_alias_offset)
1075                 mmu->base += IM_NS_ALIAS_OFFSET;
1076
1077         mmu->num_ctx = min(IPMMU_CTX_MAX, mmu->features->number_of_contexts);
1078
1079         irq = platform_get_irq(pdev, 0);
1080
1081         /*
1082          * Determine if this IPMMU instance is a root device by checking for
1083          * the lack of has_cache_leaf_nodes flag or renesas,ipmmu-main property.
1084          */
1085         if (!mmu->features->has_cache_leaf_nodes ||
1086             !of_find_property(pdev->dev.of_node, "renesas,ipmmu-main", NULL))
1087                 mmu->root = mmu;
1088         else
1089                 mmu->root = ipmmu_find_root();
1090
1091         /*
1092          * Wait until the root device has been registered for sure.
1093          */
1094         if (!mmu->root)
1095                 return -EPROBE_DEFER;
1096
1097         /* Root devices have mandatory IRQs */
1098         if (ipmmu_is_root(mmu)) {
1099                 if (irq < 0) {
1100                         dev_err(&pdev->dev, "no IRQ found\n");
1101                         return irq;
1102                 }
1103
1104                 ret = devm_request_irq(&pdev->dev, irq, ipmmu_irq, 0,
1105                                        dev_name(&pdev->dev), mmu);
1106                 if (ret < 0) {
1107                         dev_err(&pdev->dev, "failed to request IRQ %d\n", irq);
1108                         return ret;
1109                 }
1110
1111                 ipmmu_device_reset(mmu);
1112
1113                 if (mmu->features->reserved_context) {
1114                         dev_info(&pdev->dev, "IPMMU context 0 is reserved\n");
1115                         set_bit(0, mmu->ctx);
1116                 }
1117         }
1118
1119         /*
1120          * Register the IPMMU to the IOMMU subsystem in the following cases:
1121          * - R-Car Gen2 IPMMU (all devices registered)
1122          * - R-Car Gen3 IPMMU (leaf devices only - skip root IPMMU-MM device)
1123          */
1124         if (!mmu->features->has_cache_leaf_nodes || !ipmmu_is_root(mmu)) {
1125                 ret = iommu_device_sysfs_add(&mmu->iommu, &pdev->dev, NULL,
1126                                              dev_name(&pdev->dev));
1127                 if (ret)
1128                         return ret;
1129
1130                 iommu_device_set_ops(&mmu->iommu, &ipmmu_ops);
1131                 iommu_device_set_fwnode(&mmu->iommu,
1132                                         &pdev->dev.of_node->fwnode);
1133
1134                 ret = iommu_device_register(&mmu->iommu);
1135                 if (ret)
1136                         return ret;
1137
1138 #if defined(CONFIG_IOMMU_DMA)
1139                 if (!iommu_present(&platform_bus_type))
1140                         bus_set_iommu(&platform_bus_type, &ipmmu_ops);
1141 #endif
1142         }
1143
1144         /*
1145          * We can't create the ARM mapping here as it requires the bus to have
1146          * an IOMMU, which only happens when bus_set_iommu() is called in
1147          * ipmmu_init() after the probe function returns.
1148          */
1149
1150         platform_set_drvdata(pdev, mmu);
1151
1152         return 0;
1153 }
1154
1155 static int ipmmu_remove(struct platform_device *pdev)
1156 {
1157         struct ipmmu_vmsa_device *mmu = platform_get_drvdata(pdev);
1158
1159         iommu_device_sysfs_remove(&mmu->iommu);
1160         iommu_device_unregister(&mmu->iommu);
1161
1162         arm_iommu_release_mapping(mmu->mapping);
1163
1164         ipmmu_device_reset(mmu);
1165
1166         return 0;
1167 }
1168
1169 #ifdef CONFIG_PM_SLEEP
1170 static int ipmmu_resume_noirq(struct device *dev)
1171 {
1172         struct ipmmu_vmsa_device *mmu = dev_get_drvdata(dev);
1173         unsigned int i;
1174
1175         /* Reset root MMU and restore contexts */
1176         if (ipmmu_is_root(mmu)) {
1177                 ipmmu_device_reset(mmu);
1178
1179                 for (i = 0; i < mmu->num_ctx; i++) {
1180                         if (!mmu->domains[i])
1181                                 continue;
1182
1183                         ipmmu_domain_setup_context(mmu->domains[i]);
1184                 }
1185         }
1186
1187         /* Re-enable active micro-TLBs */
1188         for (i = 0; i < mmu->features->num_utlbs; i++) {
1189                 if (mmu->utlb_ctx[i] == IPMMU_CTX_INVALID)
1190                         continue;
1191
1192                 ipmmu_utlb_enable(mmu->root->domains[mmu->utlb_ctx[i]], i);
1193         }
1194
1195         return 0;
1196 }
1197
1198 static const struct dev_pm_ops ipmmu_pm  = {
1199         SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(NULL, ipmmu_resume_noirq)
1200 };
1201 #define DEV_PM_OPS      &ipmmu_pm
1202 #else
1203 #define DEV_PM_OPS      NULL
1204 #endif /* CONFIG_PM_SLEEP */
1205
1206 static struct platform_driver ipmmu_driver = {
1207         .driver = {
1208                 .name = "ipmmu-vmsa",
1209                 .of_match_table = of_match_ptr(ipmmu_of_ids),
1210                 .pm = DEV_PM_OPS,
1211         },
1212         .probe = ipmmu_probe,
1213         .remove = ipmmu_remove,
1214 };
1215
1216 static int __init ipmmu_init(void)
1217 {
1218         struct device_node *np;
1219         static bool setup_done;
1220         int ret;
1221
1222         if (setup_done)
1223                 return 0;
1224
1225         np = of_find_matching_node(NULL, ipmmu_of_ids);
1226         if (!np)
1227                 return 0;
1228
1229         of_node_put(np);
1230
1231         ret = platform_driver_register(&ipmmu_driver);
1232         if (ret < 0)
1233                 return ret;
1234
1235 #if defined(CONFIG_ARM) && !defined(CONFIG_IOMMU_DMA)
1236         if (!iommu_present(&platform_bus_type))
1237                 bus_set_iommu(&platform_bus_type, &ipmmu_ops);
1238 #endif
1239
1240         setup_done = true;
1241         return 0;
1242 }
1243 subsys_initcall(ipmmu_init);