xref: /linux/drivers/iommu/apple-dart.c (revision ce5cfb0fa20dc6454da039612e34325b7b4a8243)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Apple DART (Device Address Resolution Table) IOMMU driver
4  *
5  * Copyright (C) 2021 The Asahi Linux Contributors
6  *
7  * Based on arm/arm-smmu/arm-ssmu.c and arm/arm-smmu-v3/arm-smmu-v3.c
8  *  Copyright (C) 2013 ARM Limited
9  *  Copyright (C) 2015 ARM Limited
10  * and on exynos-iommu.c
11  *  Copyright (c) 2011,2016 Samsung Electronics Co., Ltd.
12  */
13 
14 #include <linux/atomic.h>
15 #include <linux/bitfield.h>
16 #include <linux/clk.h>
17 #include <linux/dev_printk.h>
18 #include <linux/dma-mapping.h>
19 #include <linux/err.h>
20 #include <linux/interrupt.h>
21 #include <linux/io-pgtable.h>
22 #include <linux/iommu.h>
23 #include <linux/iopoll.h>
24 #include <linux/module.h>
25 #include <linux/of.h>
26 #include <linux/of_address.h>
27 #include <linux/of_iommu.h>
28 #include <linux/of_platform.h>
29 #include <linux/pci.h>
30 #include <linux/platform_device.h>
31 #include <linux/slab.h>
32 #include <linux/swab.h>
33 #include <linux/types.h>
34 
35 #include "dma-iommu.h"
36 
37 #define DART_MAX_STREAMS 256
38 #define DART_MAX_TTBR 4
39 #define MAX_DARTS_PER_DEVICE 3
40 
41 /* Common registers */
42 
43 #define DART_PARAMS1 0x00
44 #define DART_PARAMS1_PAGE_SHIFT GENMASK(27, 24)
45 
46 #define DART_PARAMS2 0x04
47 #define DART_PARAMS2_BYPASS_SUPPORT BIT(0)
48 
49 /* T8020/T6000 registers */
50 
51 #define DART_T8020_STREAM_COMMAND 0x20
52 #define DART_T8020_STREAM_COMMAND_BUSY BIT(2)
53 #define DART_T8020_STREAM_COMMAND_INVALIDATE BIT(20)
54 
55 #define DART_T8020_STREAM_SELECT 0x34
56 
57 #define DART_T8020_ERROR 0x40
58 #define DART_T8020_ERROR_STREAM GENMASK(27, 24)
59 #define DART_T8020_ERROR_CODE GENMASK(11, 0)
60 #define DART_T8020_ERROR_FLAG BIT(31)
61 
62 #define DART_T8020_ERROR_READ_FAULT BIT(4)
63 #define DART_T8020_ERROR_WRITE_FAULT BIT(3)
64 #define DART_T8020_ERROR_NO_PTE BIT(2)
65 #define DART_T8020_ERROR_NO_PMD BIT(1)
66 #define DART_T8020_ERROR_NO_TTBR BIT(0)
67 
68 #define DART_T8020_CONFIG 0x60
69 #define DART_T8020_CONFIG_LOCK BIT(15)
70 
71 #define DART_STREAM_COMMAND_BUSY_TIMEOUT 100
72 
73 #define DART_T8020_ERROR_ADDR_HI 0x54
74 #define DART_T8020_ERROR_ADDR_LO 0x50
75 
76 #define DART_T8020_STREAMS_ENABLE 0xfc
77 
78 #define DART_T8020_TCR                  0x100
79 #define DART_T8020_TCR_TRANSLATE_ENABLE BIT(7)
80 #define DART_T8020_TCR_BYPASS_DART      BIT(8)
81 #define DART_T8020_TCR_BYPASS_DAPF      BIT(12)
82 
83 #define DART_T8020_TTBR       0x200
84 #define DART_T8020_USB4_TTBR  0x400
85 #define DART_T8020_TTBR_VALID BIT(31)
86 #define DART_T8020_TTBR_ADDR_FIELD_SHIFT 0
87 #define DART_T8020_TTBR_SHIFT 12
88 
89 /* T8110 registers */
90 
91 #define DART_T8110_PARAMS3 0x08
92 #define DART_T8110_PARAMS3_PA_WIDTH GENMASK(29, 24)
93 #define DART_T8110_PARAMS3_VA_WIDTH GENMASK(21, 16)
94 #define DART_T8110_PARAMS3_VER_MAJ GENMASK(15, 8)
95 #define DART_T8110_PARAMS3_VER_MIN GENMASK(7, 0)
96 
97 #define DART_T8110_PARAMS4 0x0c
98 #define DART_T8110_PARAMS4_NUM_CLIENTS GENMASK(24, 16)
99 #define DART_T8110_PARAMS4_NUM_SIDS GENMASK(8, 0)
100 
101 #define DART_T8110_TLB_CMD              0x80
102 #define DART_T8110_TLB_CMD_BUSY         BIT(31)
103 #define DART_T8110_TLB_CMD_OP           GENMASK(10, 8)
104 #define DART_T8110_TLB_CMD_OP_FLUSH_ALL 0
105 #define DART_T8110_TLB_CMD_OP_FLUSH_SID 1
106 #define DART_T8110_TLB_CMD_STREAM       GENMASK(7, 0)
107 
108 #define DART_T8110_ERROR 0x100
109 #define DART_T8110_ERROR_STREAM GENMASK(27, 20)
110 #define DART_T8110_ERROR_CODE GENMASK(14, 0)
111 #define DART_T8110_ERROR_FLAG BIT(31)
112 
113 #define DART_T8110_ERROR_MASK 0x104
114 
115 #define DART_T8110_ERROR_READ_FAULT BIT(5)
116 #define DART_T8110_ERROR_WRITE_FAULT BIT(4)
117 #define DART_T8110_ERROR_NO_PTE BIT(3)
118 #define DART_T8110_ERROR_NO_PMD BIT(2)
119 #define DART_T8110_ERROR_NO_PGD BIT(1)
120 #define DART_T8110_ERROR_NO_TTBR BIT(0)
121 
122 #define DART_T8110_ERROR_ADDR_LO 0x170
123 #define DART_T8110_ERROR_ADDR_HI 0x174
124 
125 #define DART_T8110_ERROR_STREAMS 0x1c0
126 
127 #define DART_T8110_PROTECT 0x200
128 #define DART_T8110_UNPROTECT 0x204
129 #define DART_T8110_PROTECT_LOCK 0x208
130 #define DART_T8110_PROTECT_TTBR_TCR BIT(0)
131 
132 #define DART_T8110_ENABLE_STREAMS  0xc00
133 #define DART_T8110_DISABLE_STREAMS 0xc20
134 
135 #define DART_T8110_TCR                  0x1000
136 #define DART_T8110_TCR_REMAP            GENMASK(11, 8)
137 #define DART_T8110_TCR_REMAP_EN         BIT(7)
138 #define DART_T8110_TCR_FOUR_LEVEL       BIT(3)
139 #define DART_T8110_TCR_BYPASS_DAPF      BIT(2)
140 #define DART_T8110_TCR_BYPASS_DART      BIT(1)
141 #define DART_T8110_TCR_TRANSLATE_ENABLE BIT(0)
142 
143 #define DART_T8110_TTBR       0x1400
144 #define DART_T8110_TTBR_VALID BIT(0)
145 #define DART_T8110_TTBR_ADDR_FIELD_SHIFT 2
146 #define DART_T8110_TTBR_SHIFT 14
147 
148 #define DART_TCR(dart, sid) ((dart)->hw->tcr + ((sid) << 2))
149 
150 #define DART_TTBR(dart, sid, idx) ((dart)->hw->ttbr + \
151 				   (((dart)->hw->ttbr_count * (sid)) << 2) + \
152 				   ((idx) << 2))
153 
154 struct apple_dart_stream_map;
155 
156 enum dart_type {
157 	DART_T8020,
158 	DART_T6000,
159 	DART_T8110,
160 };
161 
162 struct apple_dart_hw {
163 	enum dart_type type;
164 	irqreturn_t (*irq_handler)(int irq, void *dev);
165 	int (*invalidate_tlb)(struct apple_dart_stream_map *stream_map);
166 
167 	u32 oas;
168 	enum io_pgtable_fmt fmt;
169 
170 	int max_sid_count;
171 
172 	u32 lock;
173 	u32 lock_bit;
174 
175 	u32 error;
176 
177 	u32 enable_streams;
178 
179 	u32 tcr;
180 	u32 tcr_enabled;
181 	u32 tcr_disabled;
182 	u32 tcr_bypass;
183 	u32 tcr_4level;
184 
185 	u32 ttbr;
186 	u32 ttbr_valid;
187 	u32 ttbr_addr_field_shift;
188 	u32 ttbr_shift;
189 	int ttbr_count;
190 };
191 
192 /*
193  * Private structure associated with each DART device.
194  *
195  * @dev: device struct
196  * @hw: SoC-specific hardware data
197  * @regs: mapped MMIO region
198  * @irq: interrupt number, can be shared with other DARTs
199  * @clks: clocks associated with this DART
200  * @num_clks: number of @clks
201  * @lock: lock for hardware operations involving this dart
202  * @pgsize: pagesize supported by this DART
203  * @supports_bypass: indicates if this DART supports bypass mode
204  * @sid2group: maps stream ids to iommu_groups
205  * @iommu: iommu core device
206  */
207 struct apple_dart {
208 	struct device *dev;
209 	const struct apple_dart_hw *hw;
210 
211 	void __iomem *regs;
212 
213 	int irq;
214 	struct clk_bulk_data *clks;
215 	int num_clks;
216 
217 	spinlock_t lock;
218 
219 	u32 ias;
220 	u32 oas;
221 	u32 pgsize;
222 	u32 num_streams;
223 	u32 supports_bypass : 1;
224 	u32 four_level : 1;
225 
226 	struct iommu_group *sid2group[DART_MAX_STREAMS];
227 	struct iommu_device iommu;
228 
229 	u32 save_tcr[DART_MAX_STREAMS];
230 	u32 save_ttbr[DART_MAX_STREAMS][DART_MAX_TTBR];
231 };
232 
233 /*
234  * Convenience struct to identify streams.
235  *
236  * The normal variant is used inside apple_dart_master_cfg which isn't written
237  * to concurrently.
238  * The atomic variant is used inside apple_dart_domain where we have to guard
239  * against races from potential parallel calls to attach/detach_device.
240  * Note that even inside the atomic variant the apple_dart pointer is not
241  * protected: This pointer is initialized once under the domain init mutex
242  * and never changed again afterwards. Devices with different dart pointers
243  * cannot be attached to the same domain.
244  *
245  * @dart dart pointer
246  * @sid stream id bitmap
247  */
248 struct apple_dart_stream_map {
249 	struct apple_dart *dart;
250 	DECLARE_BITMAP(sidmap, DART_MAX_STREAMS);
251 };
252 struct apple_dart_atomic_stream_map {
253 	struct apple_dart *dart;
254 	atomic_long_t sidmap[BITS_TO_LONGS(DART_MAX_STREAMS)];
255 };
256 
257 /*
258  * This structure is attached to each iommu domain handled by a DART.
259  *
260  * @pgtbl_ops: pagetable ops allocated by io-pgtable
261  * @finalized: true if the domain has been completely initialized
262  * @init_lock: protects domain initialization
263  * @stream_maps: streams attached to this domain (valid for DMA/UNMANAGED only)
264  * @domain: core iommu domain pointer
265  */
266 struct apple_dart_domain {
267 	struct io_pgtable_ops *pgtbl_ops;
268 
269 	bool finalized;
270 	struct mutex init_lock;
271 	struct apple_dart_atomic_stream_map stream_maps[MAX_DARTS_PER_DEVICE];
272 
273 	struct iommu_domain domain;
274 };
275 
276 /*
277  * This structure is attached to devices with dev_iommu_priv_set() on of_xlate
278  * and contains a list of streams bound to this device.
279  * So far the worst case seen is a single device with two streams
280  * from different darts, such that this simple static array is enough.
281  *
282  * @streams: streams for this device
283  */
284 struct apple_dart_master_cfg {
285 	/* Intersection of DART capabilitles */
286 	u32 supports_bypass : 1;
287 
288 	struct apple_dart_stream_map stream_maps[MAX_DARTS_PER_DEVICE];
289 };
290 
291 /*
292  * Helper macro to iterate over apple_dart_master_cfg.stream_maps and
293  * apple_dart_domain.stream_maps
294  *
295  * @i int used as loop variable
296  * @base pointer to base struct (apple_dart_master_cfg or apple_dart_domain)
297  * @stream pointer to the apple_dart_streams struct for each loop iteration
298  */
299 #define for_each_stream_map(i, base, stream_map)                               \
300 	for (i = 0, stream_map = &(base)->stream_maps[0];                      \
301 	     i < MAX_DARTS_PER_DEVICE && stream_map->dart;                     \
302 	     stream_map = &(base)->stream_maps[++i])
303 
304 static struct platform_driver apple_dart_driver;
305 static const struct iommu_ops apple_dart_iommu_ops;
306 
to_dart_domain(struct iommu_domain * dom)307 static struct apple_dart_domain *to_dart_domain(struct iommu_domain *dom)
308 {
309 	return container_of(dom, struct apple_dart_domain, domain);
310 }
311 
312 static void
apple_dart_hw_enable_translation(struct apple_dart_stream_map * stream_map,int levels)313 apple_dart_hw_enable_translation(struct apple_dart_stream_map *stream_map, int levels)
314 {
315 	struct apple_dart *dart = stream_map->dart;
316 	u32 tcr = dart->hw->tcr_enabled;
317 	int sid;
318 
319 	if (levels == 4)
320 		tcr |= dart->hw->tcr_4level;
321 
322 	WARN_ON(levels != 3 && levels != 4);
323 	WARN_ON(levels == 4 && !dart->four_level);
324 	for_each_set_bit(sid, stream_map->sidmap, dart->num_streams)
325 		writel(tcr, dart->regs + DART_TCR(dart, sid));
326 }
327 
apple_dart_hw_disable_dma(struct apple_dart_stream_map * stream_map)328 static void apple_dart_hw_disable_dma(struct apple_dart_stream_map *stream_map)
329 {
330 	struct apple_dart *dart = stream_map->dart;
331 	int sid;
332 
333 	for_each_set_bit(sid, stream_map->sidmap, dart->num_streams)
334 		writel(dart->hw->tcr_disabled, dart->regs + DART_TCR(dart, sid));
335 }
336 
337 static void
apple_dart_hw_enable_bypass(struct apple_dart_stream_map * stream_map)338 apple_dart_hw_enable_bypass(struct apple_dart_stream_map *stream_map)
339 {
340 	struct apple_dart *dart = stream_map->dart;
341 	int sid;
342 
343 	WARN_ON(!stream_map->dart->supports_bypass);
344 	for_each_set_bit(sid, stream_map->sidmap, dart->num_streams)
345 		writel(dart->hw->tcr_bypass,
346 		       dart->regs + DART_TCR(dart, sid));
347 }
348 
apple_dart_hw_set_ttbr(struct apple_dart_stream_map * stream_map,u8 idx,phys_addr_t paddr)349 static void apple_dart_hw_set_ttbr(struct apple_dart_stream_map *stream_map,
350 				   u8 idx, phys_addr_t paddr)
351 {
352 	struct apple_dart *dart = stream_map->dart;
353 	int sid;
354 
355 	WARN_ON(paddr & ((1 << dart->hw->ttbr_shift) - 1));
356 	for_each_set_bit(sid, stream_map->sidmap, dart->num_streams)
357 		writel(dart->hw->ttbr_valid |
358 		       (paddr >> dart->hw->ttbr_shift) << dart->hw->ttbr_addr_field_shift,
359 		       dart->regs + DART_TTBR(dart, sid, idx));
360 }
361 
apple_dart_hw_clear_ttbr(struct apple_dart_stream_map * stream_map,u8 idx)362 static void apple_dart_hw_clear_ttbr(struct apple_dart_stream_map *stream_map,
363 				     u8 idx)
364 {
365 	struct apple_dart *dart = stream_map->dart;
366 	int sid;
367 
368 	for_each_set_bit(sid, stream_map->sidmap, dart->num_streams)
369 		writel(0, dart->regs + DART_TTBR(dart, sid, idx));
370 }
371 
372 static void
apple_dart_hw_clear_all_ttbrs(struct apple_dart_stream_map * stream_map)373 apple_dart_hw_clear_all_ttbrs(struct apple_dart_stream_map *stream_map)
374 {
375 	int i;
376 
377 	for (i = 0; i < stream_map->dart->hw->ttbr_count; ++i)
378 		apple_dart_hw_clear_ttbr(stream_map, i);
379 }
380 
381 static int
apple_dart_t8020_hw_stream_command(struct apple_dart_stream_map * stream_map,u32 command)382 apple_dart_t8020_hw_stream_command(struct apple_dart_stream_map *stream_map,
383 			     u32 command)
384 {
385 	unsigned long flags;
386 	int ret, i;
387 	u32 command_reg;
388 
389 	spin_lock_irqsave(&stream_map->dart->lock, flags);
390 
391 	for (i = 0; i < BITS_TO_U32(stream_map->dart->num_streams); i++)
392 		writel(stream_map->sidmap[i],
393 		       stream_map->dart->regs + DART_T8020_STREAM_SELECT + 4 * i);
394 	writel(command, stream_map->dart->regs + DART_T8020_STREAM_COMMAND);
395 
396 	ret = readl_poll_timeout_atomic(
397 		stream_map->dart->regs + DART_T8020_STREAM_COMMAND, command_reg,
398 		!(command_reg & DART_T8020_STREAM_COMMAND_BUSY), 1,
399 		DART_STREAM_COMMAND_BUSY_TIMEOUT);
400 
401 	spin_unlock_irqrestore(&stream_map->dart->lock, flags);
402 
403 	if (ret) {
404 		dev_err(stream_map->dart->dev,
405 			"busy bit did not clear after command %x for streams %lx\n",
406 			command, stream_map->sidmap[0]);
407 		return ret;
408 	}
409 
410 	return 0;
411 }
412 
413 static int
apple_dart_t8110_hw_tlb_command(struct apple_dart_stream_map * stream_map,u32 command)414 apple_dart_t8110_hw_tlb_command(struct apple_dart_stream_map *stream_map,
415 				u32 command)
416 {
417 	struct apple_dart *dart = stream_map->dart;
418 	unsigned long flags;
419 	int ret = 0;
420 	int sid;
421 
422 	spin_lock_irqsave(&dart->lock, flags);
423 
424 	for_each_set_bit(sid, stream_map->sidmap, dart->num_streams) {
425 		u32 val = FIELD_PREP(DART_T8110_TLB_CMD_OP, command) |
426 			FIELD_PREP(DART_T8110_TLB_CMD_STREAM, sid);
427 		writel(val, dart->regs + DART_T8110_TLB_CMD);
428 
429 		ret = readl_poll_timeout_atomic(
430 			dart->regs + DART_T8110_TLB_CMD, val,
431 			!(val & DART_T8110_TLB_CMD_BUSY), 1,
432 			DART_STREAM_COMMAND_BUSY_TIMEOUT);
433 
434 		if (ret)
435 			break;
436 
437 	}
438 
439 	spin_unlock_irqrestore(&dart->lock, flags);
440 
441 	if (ret) {
442 		dev_err(stream_map->dart->dev,
443 			"busy bit did not clear after command %x for stream %d\n",
444 			command, sid);
445 		return ret;
446 	}
447 
448 	return 0;
449 }
450 
451 static int
apple_dart_t8020_hw_invalidate_tlb(struct apple_dart_stream_map * stream_map)452 apple_dart_t8020_hw_invalidate_tlb(struct apple_dart_stream_map *stream_map)
453 {
454 	return apple_dart_t8020_hw_stream_command(
455 		stream_map, DART_T8020_STREAM_COMMAND_INVALIDATE);
456 }
457 
458 static int
apple_dart_t8110_hw_invalidate_tlb(struct apple_dart_stream_map * stream_map)459 apple_dart_t8110_hw_invalidate_tlb(struct apple_dart_stream_map *stream_map)
460 {
461 	return apple_dart_t8110_hw_tlb_command(
462 		stream_map, DART_T8110_TLB_CMD_OP_FLUSH_SID);
463 }
464 
apple_dart_hw_reset(struct apple_dart * dart)465 static int apple_dart_hw_reset(struct apple_dart *dart)
466 {
467 	u32 config;
468 	struct apple_dart_stream_map stream_map;
469 	int i;
470 
471 	config = readl(dart->regs + dart->hw->lock);
472 	if (config & dart->hw->lock_bit) {
473 		dev_err(dart->dev, "DART is locked down until reboot: %08x\n",
474 			config);
475 		return -EINVAL;
476 	}
477 
478 	stream_map.dart = dart;
479 	bitmap_zero(stream_map.sidmap, DART_MAX_STREAMS);
480 	bitmap_set(stream_map.sidmap, 0, dart->num_streams);
481 	apple_dart_hw_disable_dma(&stream_map);
482 	apple_dart_hw_clear_all_ttbrs(&stream_map);
483 
484 	/* enable all streams globally since TCR is used to control isolation */
485 	for (i = 0; i < BITS_TO_U32(dart->num_streams); i++)
486 		writel(U32_MAX, dart->regs + dart->hw->enable_streams + 4 * i);
487 
488 	/* clear any pending errors before the interrupt is unmasked */
489 	writel(readl(dart->regs + dart->hw->error), dart->regs + dart->hw->error);
490 
491 	if (dart->hw->type == DART_T8110)
492 		writel(0,  dart->regs + DART_T8110_ERROR_MASK);
493 
494 	return dart->hw->invalidate_tlb(&stream_map);
495 }
496 
apple_dart_domain_flush_tlb(struct apple_dart_domain * domain)497 static void apple_dart_domain_flush_tlb(struct apple_dart_domain *domain)
498 {
499 	int i, j;
500 	struct apple_dart_atomic_stream_map *domain_stream_map;
501 	struct apple_dart_stream_map stream_map;
502 
503 	for_each_stream_map(i, domain, domain_stream_map) {
504 		stream_map.dart = domain_stream_map->dart;
505 
506 		for (j = 0; j < BITS_TO_LONGS(stream_map.dart->num_streams); j++)
507 			stream_map.sidmap[j] = atomic_long_read(&domain_stream_map->sidmap[j]);
508 
509 		stream_map.dart->hw->invalidate_tlb(&stream_map);
510 	}
511 }
512 
apple_dart_flush_iotlb_all(struct iommu_domain * domain)513 static void apple_dart_flush_iotlb_all(struct iommu_domain *domain)
514 {
515 	apple_dart_domain_flush_tlb(to_dart_domain(domain));
516 }
517 
apple_dart_iotlb_sync(struct iommu_domain * domain,struct iommu_iotlb_gather * gather)518 static void apple_dart_iotlb_sync(struct iommu_domain *domain,
519 				  struct iommu_iotlb_gather *gather)
520 {
521 	apple_dart_domain_flush_tlb(to_dart_domain(domain));
522 }
523 
apple_dart_iotlb_sync_map(struct iommu_domain * domain,unsigned long iova,size_t size)524 static int apple_dart_iotlb_sync_map(struct iommu_domain *domain,
525 				     unsigned long iova, size_t size)
526 {
527 	apple_dart_domain_flush_tlb(to_dart_domain(domain));
528 	return 0;
529 }
530 
apple_dart_iova_to_phys(struct iommu_domain * domain,dma_addr_t iova)531 static phys_addr_t apple_dart_iova_to_phys(struct iommu_domain *domain,
532 					   dma_addr_t iova)
533 {
534 	struct apple_dart_domain *dart_domain = to_dart_domain(domain);
535 	struct io_pgtable_ops *ops = dart_domain->pgtbl_ops;
536 
537 	if (!ops)
538 		return 0;
539 
540 	return ops->iova_to_phys(ops, iova);
541 }
542 
apple_dart_map_pages(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)543 static int apple_dart_map_pages(struct iommu_domain *domain, unsigned long iova,
544 				phys_addr_t paddr, size_t pgsize,
545 				size_t pgcount, int prot, gfp_t gfp,
546 				size_t *mapped)
547 {
548 	struct apple_dart_domain *dart_domain = to_dart_domain(domain);
549 	struct io_pgtable_ops *ops = dart_domain->pgtbl_ops;
550 
551 	if (!ops)
552 		return -ENODEV;
553 
554 	return ops->map_pages(ops, iova, paddr, pgsize, pgcount, prot, gfp,
555 			      mapped);
556 }
557 
apple_dart_unmap_pages(struct iommu_domain * domain,unsigned long iova,size_t pgsize,size_t pgcount,struct iommu_iotlb_gather * gather)558 static size_t apple_dart_unmap_pages(struct iommu_domain *domain,
559 				     unsigned long iova, size_t pgsize,
560 				     size_t pgcount,
561 				     struct iommu_iotlb_gather *gather)
562 {
563 	struct apple_dart_domain *dart_domain = to_dart_domain(domain);
564 	struct io_pgtable_ops *ops = dart_domain->pgtbl_ops;
565 
566 	return ops->unmap_pages(ops, iova, pgsize, pgcount, gather);
567 }
568 
569 static void
apple_dart_setup_translation(struct apple_dart_domain * domain,struct apple_dart_stream_map * stream_map)570 apple_dart_setup_translation(struct apple_dart_domain *domain,
571 			     struct apple_dart_stream_map *stream_map)
572 {
573 	int i;
574 	struct io_pgtable_cfg *pgtbl_cfg =
575 		&io_pgtable_ops_to_pgtable(domain->pgtbl_ops)->cfg;
576 
577 	for (i = 0; i < pgtbl_cfg->apple_dart_cfg.n_ttbrs; ++i)
578 		apple_dart_hw_set_ttbr(stream_map, i,
579 				       pgtbl_cfg->apple_dart_cfg.ttbr[i]);
580 	for (; i < stream_map->dart->hw->ttbr_count; ++i)
581 		apple_dart_hw_clear_ttbr(stream_map, i);
582 
583 	apple_dart_hw_enable_translation(stream_map,
584 					 pgtbl_cfg->apple_dart_cfg.n_levels);
585 	stream_map->dart->hw->invalidate_tlb(stream_map);
586 }
587 
apple_dart_finalize_domain(struct apple_dart_domain * dart_domain,struct apple_dart_master_cfg * cfg)588 static int apple_dart_finalize_domain(struct apple_dart_domain *dart_domain,
589 				      struct apple_dart_master_cfg *cfg)
590 {
591 	struct apple_dart *dart = cfg->stream_maps[0].dart;
592 	struct io_pgtable_cfg pgtbl_cfg;
593 	int ret = 0;
594 	int i, j;
595 
596 	if (dart->pgsize > PAGE_SIZE)
597 		return -EINVAL;
598 
599 	mutex_lock(&dart_domain->init_lock);
600 
601 	if (dart_domain->finalized)
602 		goto done;
603 
604 	for (i = 0; i < MAX_DARTS_PER_DEVICE; ++i) {
605 		dart_domain->stream_maps[i].dart = cfg->stream_maps[i].dart;
606 		for (j = 0; j < BITS_TO_LONGS(dart->num_streams); j++)
607 			atomic_long_set(&dart_domain->stream_maps[i].sidmap[j],
608 					cfg->stream_maps[i].sidmap[j]);
609 	}
610 
611 	pgtbl_cfg = (struct io_pgtable_cfg){
612 		.pgsize_bitmap = dart->pgsize,
613 		.ias = dart->ias,
614 		.oas = dart->oas,
615 		.coherent_walk = 1,
616 		.iommu_dev = dart->dev,
617 	};
618 
619 	dart_domain->pgtbl_ops = alloc_io_pgtable_ops(dart->hw->fmt, &pgtbl_cfg,
620 						      &dart_domain->domain);
621 	if (!dart_domain->pgtbl_ops) {
622 		ret = -ENOMEM;
623 		goto done;
624 	}
625 
626 	dart_domain->domain.pgsize_bitmap = pgtbl_cfg.pgsize_bitmap;
627 	dart_domain->domain.geometry.aperture_start = 0;
628 	dart_domain->domain.geometry.aperture_end =
629 		(dma_addr_t)DMA_BIT_MASK(pgtbl_cfg.ias);
630 	dart_domain->domain.geometry.force_aperture = true;
631 
632 	dart_domain->finalized = true;
633 
634 done:
635 	mutex_unlock(&dart_domain->init_lock);
636 	return ret;
637 }
638 
639 static int
apple_dart_mod_streams(struct apple_dart_atomic_stream_map * domain_maps,struct apple_dart_stream_map * master_maps,bool add_streams)640 apple_dart_mod_streams(struct apple_dart_atomic_stream_map *domain_maps,
641 		       struct apple_dart_stream_map *master_maps,
642 		       bool add_streams)
643 {
644 	int i, j;
645 
646 	for (i = 0; i < MAX_DARTS_PER_DEVICE; ++i) {
647 		if (domain_maps[i].dart != master_maps[i].dart)
648 			return -EINVAL;
649 	}
650 
651 	for (i = 0; i < MAX_DARTS_PER_DEVICE; ++i) {
652 		if (!domain_maps[i].dart)
653 			break;
654 		for (j = 0; j < BITS_TO_LONGS(domain_maps[i].dart->num_streams); j++) {
655 			if (add_streams)
656 				atomic_long_or(master_maps[i].sidmap[j],
657 					       &domain_maps[i].sidmap[j]);
658 			else
659 				atomic_long_and(~master_maps[i].sidmap[j],
660 						&domain_maps[i].sidmap[j]);
661 		}
662 	}
663 
664 	return 0;
665 }
666 
apple_dart_domain_add_streams(struct apple_dart_domain * domain,struct apple_dart_master_cfg * cfg)667 static int apple_dart_domain_add_streams(struct apple_dart_domain *domain,
668 					 struct apple_dart_master_cfg *cfg)
669 {
670 	return apple_dart_mod_streams(domain->stream_maps, cfg->stream_maps,
671 				      true);
672 }
673 
apple_dart_attach_dev_paging(struct iommu_domain * domain,struct device * dev,struct iommu_domain * old)674 static int apple_dart_attach_dev_paging(struct iommu_domain *domain,
675 					struct device *dev,
676 					struct iommu_domain *old)
677 {
678 	int ret, i;
679 	struct apple_dart_stream_map *stream_map;
680 	struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev);
681 	struct apple_dart_domain *dart_domain = to_dart_domain(domain);
682 
683 	ret = apple_dart_finalize_domain(dart_domain, cfg);
684 	if (ret)
685 		return ret;
686 
687 	ret = apple_dart_domain_add_streams(dart_domain, cfg);
688 	if (ret)
689 		return ret;
690 
691 	for_each_stream_map(i, cfg, stream_map)
692 		apple_dart_setup_translation(dart_domain, stream_map);
693 	return 0;
694 }
695 
apple_dart_attach_dev_identity(struct iommu_domain * domain,struct device * dev,struct iommu_domain * old)696 static int apple_dart_attach_dev_identity(struct iommu_domain *domain,
697 					  struct device *dev,
698 					  struct iommu_domain *old)
699 {
700 	struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev);
701 	struct apple_dart_stream_map *stream_map;
702 	int i;
703 
704 	if (!cfg->supports_bypass)
705 		return -EINVAL;
706 
707 	for_each_stream_map(i, cfg, stream_map)
708 		apple_dart_hw_enable_bypass(stream_map);
709 	return 0;
710 }
711 
712 static const struct iommu_domain_ops apple_dart_identity_ops = {
713 	.attach_dev = apple_dart_attach_dev_identity,
714 };
715 
716 static struct iommu_domain apple_dart_identity_domain = {
717 	.type = IOMMU_DOMAIN_IDENTITY,
718 	.ops = &apple_dart_identity_ops,
719 };
720 
apple_dart_attach_dev_blocked(struct iommu_domain * domain,struct device * dev,struct iommu_domain * old)721 static int apple_dart_attach_dev_blocked(struct iommu_domain *domain,
722 					 struct device *dev,
723 					 struct iommu_domain *old)
724 {
725 	struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev);
726 	struct apple_dart_stream_map *stream_map;
727 	int i;
728 
729 	for_each_stream_map(i, cfg, stream_map)
730 		apple_dart_hw_disable_dma(stream_map);
731 	return 0;
732 }
733 
734 static const struct iommu_domain_ops apple_dart_blocked_ops = {
735 	.attach_dev = apple_dart_attach_dev_blocked,
736 };
737 
738 static struct iommu_domain apple_dart_blocked_domain = {
739 	.type = IOMMU_DOMAIN_BLOCKED,
740 	.ops = &apple_dart_blocked_ops,
741 };
742 
apple_dart_probe_device(struct device * dev)743 static struct iommu_device *apple_dart_probe_device(struct device *dev)
744 {
745 	struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev);
746 	struct apple_dart_stream_map *stream_map;
747 	int i;
748 
749 	if (!cfg)
750 		return ERR_PTR(-ENODEV);
751 
752 	for_each_stream_map(i, cfg, stream_map)
753 		device_link_add(
754 			dev, stream_map->dart->dev,
755 			DL_FLAG_PM_RUNTIME | DL_FLAG_AUTOREMOVE_SUPPLIER);
756 
757 	return &cfg->stream_maps[0].dart->iommu;
758 }
759 
apple_dart_release_device(struct device * dev)760 static void apple_dart_release_device(struct device *dev)
761 {
762 	struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev);
763 
764 	kfree(cfg);
765 }
766 
apple_dart_domain_alloc_paging(struct device * dev)767 static struct iommu_domain *apple_dart_domain_alloc_paging(struct device *dev)
768 {
769 	struct apple_dart_domain *dart_domain;
770 
771 	dart_domain = kzalloc(sizeof(*dart_domain), GFP_KERNEL);
772 	if (!dart_domain)
773 		return NULL;
774 
775 	mutex_init(&dart_domain->init_lock);
776 
777 	if (dev) {
778 		struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev);
779 		int ret;
780 
781 		ret = apple_dart_finalize_domain(dart_domain, cfg);
782 		if (ret) {
783 			kfree(dart_domain);
784 			return ERR_PTR(ret);
785 		}
786 	}
787 	return &dart_domain->domain;
788 }
789 
apple_dart_domain_free(struct iommu_domain * domain)790 static void apple_dart_domain_free(struct iommu_domain *domain)
791 {
792 	struct apple_dart_domain *dart_domain = to_dart_domain(domain);
793 
794 	free_io_pgtable_ops(dart_domain->pgtbl_ops);
795 
796 	kfree(dart_domain);
797 }
798 
apple_dart_of_xlate(struct device * dev,const struct of_phandle_args * args)799 static int apple_dart_of_xlate(struct device *dev,
800 			       const struct of_phandle_args *args)
801 {
802 	struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev);
803 	struct platform_device *iommu_pdev = of_find_device_by_node(args->np);
804 	struct apple_dart *dart = platform_get_drvdata(iommu_pdev);
805 	struct apple_dart *cfg_dart;
806 	int i, sid;
807 
808 	put_device(&iommu_pdev->dev);
809 
810 	if (args->args_count != 1)
811 		return -EINVAL;
812 	sid = args->args[0];
813 
814 	if (!cfg) {
815 		cfg = kzalloc(sizeof(*cfg), GFP_KERNEL);
816 		if (!cfg)
817 			return -ENOMEM;
818 		/* Will be ANDed with DART capabilities */
819 		cfg->supports_bypass = true;
820 	}
821 	dev_iommu_priv_set(dev, cfg);
822 
823 	cfg_dart = cfg->stream_maps[0].dart;
824 	if (cfg_dart) {
825 		if (cfg_dart->pgsize != dart->pgsize)
826 			return -EINVAL;
827 		if (cfg_dart->ias != dart->ias)
828 			return -EINVAL;
829 	}
830 
831 	cfg->supports_bypass &= dart->supports_bypass;
832 
833 	for (i = 0; i < MAX_DARTS_PER_DEVICE; ++i) {
834 		if (cfg->stream_maps[i].dart == dart) {
835 			set_bit(sid, cfg->stream_maps[i].sidmap);
836 			return 0;
837 		}
838 	}
839 	for (i = 0; i < MAX_DARTS_PER_DEVICE; ++i) {
840 		if (!cfg->stream_maps[i].dart) {
841 			cfg->stream_maps[i].dart = dart;
842 			set_bit(sid, cfg->stream_maps[i].sidmap);
843 			return 0;
844 		}
845 	}
846 
847 	return -EINVAL;
848 }
849 
850 static DEFINE_MUTEX(apple_dart_groups_lock);
851 
apple_dart_release_group(void * iommu_data)852 static void apple_dart_release_group(void *iommu_data)
853 {
854 	int i, sid;
855 	struct apple_dart_stream_map *stream_map;
856 	struct apple_dart_master_cfg *group_master_cfg = iommu_data;
857 
858 	mutex_lock(&apple_dart_groups_lock);
859 
860 	for_each_stream_map(i, group_master_cfg, stream_map)
861 		for_each_set_bit(sid, stream_map->sidmap, stream_map->dart->num_streams)
862 			stream_map->dart->sid2group[sid] = NULL;
863 
864 	kfree(iommu_data);
865 	mutex_unlock(&apple_dart_groups_lock);
866 }
867 
apple_dart_merge_master_cfg(struct apple_dart_master_cfg * dst,struct apple_dart_master_cfg * src)868 static int apple_dart_merge_master_cfg(struct apple_dart_master_cfg *dst,
869 				       struct apple_dart_master_cfg *src)
870 {
871 	/*
872 	 * We know that this function is only called for groups returned from
873 	 * pci_device_group and that all Apple Silicon platforms never spread
874 	 * PCIe devices from the same bus across multiple DARTs such that we can
875 	 * just assume that both src and dst only have the same single DART.
876 	 */
877 	if (src->stream_maps[1].dart)
878 		return -EINVAL;
879 	if (dst->stream_maps[1].dart)
880 		return -EINVAL;
881 	if (src->stream_maps[0].dart != dst->stream_maps[0].dart)
882 		return -EINVAL;
883 
884 	bitmap_or(dst->stream_maps[0].sidmap,
885 		  dst->stream_maps[0].sidmap,
886 		  src->stream_maps[0].sidmap,
887 		  dst->stream_maps[0].dart->num_streams);
888 	return 0;
889 }
890 
apple_dart_device_group(struct device * dev)891 static struct iommu_group *apple_dart_device_group(struct device *dev)
892 {
893 	int i, sid;
894 	struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev);
895 	struct apple_dart_stream_map *stream_map;
896 	struct apple_dart_master_cfg *group_master_cfg;
897 	struct iommu_group *group = NULL;
898 	struct iommu_group *res = ERR_PTR(-EINVAL);
899 
900 	mutex_lock(&apple_dart_groups_lock);
901 
902 	for_each_stream_map(i, cfg, stream_map) {
903 		for_each_set_bit(sid, stream_map->sidmap, stream_map->dart->num_streams) {
904 			struct iommu_group *stream_group =
905 				stream_map->dart->sid2group[sid];
906 
907 			if (group && group != stream_group) {
908 				res = ERR_PTR(-EINVAL);
909 				goto out;
910 			}
911 
912 			group = stream_group;
913 		}
914 	}
915 
916 	if (group) {
917 		res = iommu_group_ref_get(group);
918 		goto out;
919 	}
920 
921 #ifdef CONFIG_PCI
922 	if (dev_is_pci(dev))
923 		group = pci_device_group(dev);
924 	else
925 #endif
926 		group = generic_device_group(dev);
927 
928 	res = ERR_PTR(-ENOMEM);
929 	if (!group)
930 		goto out;
931 
932 	group_master_cfg = iommu_group_get_iommudata(group);
933 	if (group_master_cfg) {
934 		int ret;
935 
936 		ret = apple_dart_merge_master_cfg(group_master_cfg, cfg);
937 		if (ret) {
938 			dev_err(dev, "Failed to merge DART IOMMU groups.\n");
939 			iommu_group_put(group);
940 			res = ERR_PTR(ret);
941 			goto out;
942 		}
943 	} else {
944 		group_master_cfg = kmemdup(cfg, sizeof(*group_master_cfg),
945 					   GFP_KERNEL);
946 		if (!group_master_cfg) {
947 			iommu_group_put(group);
948 			goto out;
949 		}
950 
951 		iommu_group_set_iommudata(group, group_master_cfg,
952 			apple_dart_release_group);
953 	}
954 
955 	for_each_stream_map(i, cfg, stream_map)
956 		for_each_set_bit(sid, stream_map->sidmap, stream_map->dart->num_streams)
957 			stream_map->dart->sid2group[sid] = group;
958 
959 	res = group;
960 
961 out:
962 	mutex_unlock(&apple_dart_groups_lock);
963 	return res;
964 }
965 
apple_dart_def_domain_type(struct device * dev)966 static int apple_dart_def_domain_type(struct device *dev)
967 {
968 	struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev);
969 
970 	if (cfg->stream_maps[0].dart->pgsize > PAGE_SIZE)
971 		return IOMMU_DOMAIN_IDENTITY;
972 	if (!cfg->supports_bypass)
973 		return IOMMU_DOMAIN_DMA;
974 
975 	return 0;
976 }
977 
978 #ifndef CONFIG_PCIE_APPLE_MSI_DOORBELL_ADDR
979 /* Keep things compiling when CONFIG_PCI_APPLE isn't selected */
980 #define CONFIG_PCIE_APPLE_MSI_DOORBELL_ADDR	0
981 #endif
982 #define DOORBELL_ADDR	(CONFIG_PCIE_APPLE_MSI_DOORBELL_ADDR & PAGE_MASK)
983 
apple_dart_get_resv_regions(struct device * dev,struct list_head * head)984 static void apple_dart_get_resv_regions(struct device *dev,
985 					struct list_head *head)
986 {
987 	if (IS_ENABLED(CONFIG_PCIE_APPLE) && dev_is_pci(dev)) {
988 		struct iommu_resv_region *region;
989 		int prot = IOMMU_WRITE | IOMMU_NOEXEC | IOMMU_MMIO;
990 
991 		region = iommu_alloc_resv_region(DOORBELL_ADDR,
992 						 PAGE_SIZE, prot,
993 						 IOMMU_RESV_MSI, GFP_KERNEL);
994 		if (!region)
995 			return;
996 
997 		list_add_tail(&region->list, head);
998 	}
999 
1000 	iommu_dma_get_resv_regions(dev, head);
1001 }
1002 
1003 static const struct iommu_ops apple_dart_iommu_ops = {
1004 	.identity_domain = &apple_dart_identity_domain,
1005 	.blocked_domain = &apple_dart_blocked_domain,
1006 	.domain_alloc_paging = apple_dart_domain_alloc_paging,
1007 	.probe_device = apple_dart_probe_device,
1008 	.release_device = apple_dart_release_device,
1009 	.device_group = apple_dart_device_group,
1010 	.of_xlate = apple_dart_of_xlate,
1011 	.def_domain_type = apple_dart_def_domain_type,
1012 	.get_resv_regions = apple_dart_get_resv_regions,
1013 	.owner = THIS_MODULE,
1014 	.default_domain_ops = &(const struct iommu_domain_ops) {
1015 		.attach_dev	= apple_dart_attach_dev_paging,
1016 		.map_pages	= apple_dart_map_pages,
1017 		.unmap_pages	= apple_dart_unmap_pages,
1018 		.flush_iotlb_all = apple_dart_flush_iotlb_all,
1019 		.iotlb_sync	= apple_dart_iotlb_sync,
1020 		.iotlb_sync_map	= apple_dart_iotlb_sync_map,
1021 		.iova_to_phys	= apple_dart_iova_to_phys,
1022 		.free		= apple_dart_domain_free,
1023 	}
1024 };
1025 
apple_dart_t8020_irq(int irq,void * dev)1026 static irqreturn_t apple_dart_t8020_irq(int irq, void *dev)
1027 {
1028 	struct apple_dart *dart = dev;
1029 	const char *fault_name = NULL;
1030 	u32 error = readl(dart->regs + DART_T8020_ERROR);
1031 	u32 error_code = FIELD_GET(DART_T8020_ERROR_CODE, error);
1032 	u32 addr_lo = readl(dart->regs + DART_T8020_ERROR_ADDR_LO);
1033 	u32 addr_hi = readl(dart->regs + DART_T8020_ERROR_ADDR_HI);
1034 	u64 addr = addr_lo | (((u64)addr_hi) << 32);
1035 	u8 stream_idx = FIELD_GET(DART_T8020_ERROR_STREAM, error);
1036 
1037 	if (!(error & DART_T8020_ERROR_FLAG))
1038 		return IRQ_NONE;
1039 
1040 	/* there should only be a single bit set but let's use == to be sure */
1041 	if (error_code == DART_T8020_ERROR_READ_FAULT)
1042 		fault_name = "READ FAULT";
1043 	else if (error_code == DART_T8020_ERROR_WRITE_FAULT)
1044 		fault_name = "WRITE FAULT";
1045 	else if (error_code == DART_T8020_ERROR_NO_PTE)
1046 		fault_name = "NO PTE FOR IOVA";
1047 	else if (error_code == DART_T8020_ERROR_NO_PMD)
1048 		fault_name = "NO PMD FOR IOVA";
1049 	else if (error_code == DART_T8020_ERROR_NO_TTBR)
1050 		fault_name = "NO TTBR FOR IOVA";
1051 	else
1052 		fault_name = "unknown";
1053 
1054 	dev_err_ratelimited(
1055 		dart->dev,
1056 		"translation fault: status:0x%x stream:%d code:0x%x (%s) at 0x%llx",
1057 		error, stream_idx, error_code, fault_name, addr);
1058 
1059 	writel(error, dart->regs + DART_T8020_ERROR);
1060 	return IRQ_HANDLED;
1061 }
1062 
apple_dart_t8110_irq(int irq,void * dev)1063 static irqreturn_t apple_dart_t8110_irq(int irq, void *dev)
1064 {
1065 	struct apple_dart *dart = dev;
1066 	const char *fault_name = NULL;
1067 	u32 error = readl(dart->regs + DART_T8110_ERROR);
1068 	u32 error_code = FIELD_GET(DART_T8110_ERROR_CODE, error);
1069 	u32 addr_lo = readl(dart->regs + DART_T8110_ERROR_ADDR_LO);
1070 	u32 addr_hi = readl(dart->regs + DART_T8110_ERROR_ADDR_HI);
1071 	u64 addr = addr_lo | (((u64)addr_hi) << 32);
1072 	u8 stream_idx = FIELD_GET(DART_T8110_ERROR_STREAM, error);
1073 
1074 	if (!(error & DART_T8110_ERROR_FLAG))
1075 		return IRQ_NONE;
1076 
1077 	/* there should only be a single bit set but let's use == to be sure */
1078 	if (error_code == DART_T8110_ERROR_READ_FAULT)
1079 		fault_name = "READ FAULT";
1080 	else if (error_code == DART_T8110_ERROR_WRITE_FAULT)
1081 		fault_name = "WRITE FAULT";
1082 	else if (error_code == DART_T8110_ERROR_NO_PTE)
1083 		fault_name = "NO PTE FOR IOVA";
1084 	else if (error_code == DART_T8110_ERROR_NO_PMD)
1085 		fault_name = "NO PMD FOR IOVA";
1086 	else if (error_code == DART_T8110_ERROR_NO_PGD)
1087 		fault_name = "NO PGD FOR IOVA";
1088 	else if (error_code == DART_T8110_ERROR_NO_TTBR)
1089 		fault_name = "NO TTBR FOR IOVA";
1090 	else
1091 		fault_name = "unknown";
1092 
1093 	dev_err_ratelimited(
1094 		dart->dev,
1095 		"translation fault: status:0x%x stream:%d code:0x%x (%s) at 0x%llx",
1096 		error, stream_idx, error_code, fault_name, addr);
1097 
1098 	writel(error, dart->regs + DART_T8110_ERROR);
1099 	for (int i = 0; i < BITS_TO_U32(dart->num_streams); i++)
1100 		writel(U32_MAX, dart->regs + DART_T8110_ERROR_STREAMS + 4 * i);
1101 
1102 	return IRQ_HANDLED;
1103 }
1104 
apple_dart_probe(struct platform_device * pdev)1105 static int apple_dart_probe(struct platform_device *pdev)
1106 {
1107 	int ret;
1108 	u32 dart_params[4];
1109 	struct resource *res;
1110 	struct apple_dart *dart;
1111 	struct device *dev = &pdev->dev;
1112 
1113 	dart = devm_kzalloc(dev, sizeof(*dart), GFP_KERNEL);
1114 	if (!dart)
1115 		return -ENOMEM;
1116 
1117 	dart->dev = dev;
1118 	dart->hw = of_device_get_match_data(dev);
1119 	spin_lock_init(&dart->lock);
1120 
1121 	dart->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
1122 	if (IS_ERR(dart->regs))
1123 		return PTR_ERR(dart->regs);
1124 
1125 	if (resource_size(res) < 0x4000) {
1126 		dev_err(dev, "MMIO region too small (%pr)\n", res);
1127 		return -EINVAL;
1128 	}
1129 
1130 	dart->irq = platform_get_irq(pdev, 0);
1131 	if (dart->irq < 0)
1132 		return -ENODEV;
1133 
1134 	ret = devm_clk_bulk_get_all(dev, &dart->clks);
1135 	if (ret < 0)
1136 		return ret;
1137 	dart->num_clks = ret;
1138 
1139 	ret = clk_bulk_prepare_enable(dart->num_clks, dart->clks);
1140 	if (ret)
1141 		return ret;
1142 
1143 	dart_params[0] = readl(dart->regs + DART_PARAMS1);
1144 	dart_params[1] = readl(dart->regs + DART_PARAMS2);
1145 	dart->pgsize = 1 << FIELD_GET(DART_PARAMS1_PAGE_SHIFT, dart_params[0]);
1146 	dart->supports_bypass = dart_params[1] & DART_PARAMS2_BYPASS_SUPPORT;
1147 
1148 	switch (dart->hw->type) {
1149 	case DART_T8020:
1150 	case DART_T6000:
1151 		dart->ias = 32;
1152 		dart->oas = dart->hw->oas;
1153 		dart->num_streams = dart->hw->max_sid_count;
1154 		break;
1155 
1156 	case DART_T8110:
1157 		dart_params[2] = readl(dart->regs + DART_T8110_PARAMS3);
1158 		dart_params[3] = readl(dart->regs + DART_T8110_PARAMS4);
1159 		dart->ias = FIELD_GET(DART_T8110_PARAMS3_VA_WIDTH, dart_params[2]);
1160 		dart->oas = FIELD_GET(DART_T8110_PARAMS3_PA_WIDTH, dart_params[2]);
1161 		dart->num_streams = FIELD_GET(DART_T8110_PARAMS4_NUM_SIDS, dart_params[3]);
1162 		dart->four_level = dart->ias > 36;
1163 		break;
1164 	}
1165 
1166 	if (dart->num_streams > DART_MAX_STREAMS) {
1167 		dev_err(&pdev->dev, "Too many streams (%d > %d)\n",
1168 			dart->num_streams, DART_MAX_STREAMS);
1169 		ret = -EINVAL;
1170 		goto err_clk_disable;
1171 	}
1172 
1173 	ret = apple_dart_hw_reset(dart);
1174 	if (ret)
1175 		goto err_clk_disable;
1176 
1177 	ret = request_irq(dart->irq, dart->hw->irq_handler, IRQF_SHARED,
1178 			  "apple-dart fault handler", dart);
1179 	if (ret)
1180 		goto err_clk_disable;
1181 
1182 	platform_set_drvdata(pdev, dart);
1183 
1184 	ret = iommu_device_sysfs_add(&dart->iommu, dev, NULL, "apple-dart.%s",
1185 				     dev_name(&pdev->dev));
1186 	if (ret)
1187 		goto err_free_irq;
1188 
1189 	ret = iommu_device_register(&dart->iommu, &apple_dart_iommu_ops, dev);
1190 	if (ret)
1191 		goto err_sysfs_remove;
1192 
1193 	dev_info(
1194 		&pdev->dev,
1195 		"DART [pagesize %x, %d streams, bypass support: %d, bypass forced: %d, AS %d -> %d] initialized\n",
1196 		dart->pgsize, dart->num_streams, dart->supports_bypass,
1197 		dart->pgsize > PAGE_SIZE, dart->ias, dart->oas);
1198 	return 0;
1199 
1200 err_sysfs_remove:
1201 	iommu_device_sysfs_remove(&dart->iommu);
1202 err_free_irq:
1203 	free_irq(dart->irq, dart);
1204 err_clk_disable:
1205 	clk_bulk_disable_unprepare(dart->num_clks, dart->clks);
1206 
1207 	return ret;
1208 }
1209 
apple_dart_remove(struct platform_device * pdev)1210 static void apple_dart_remove(struct platform_device *pdev)
1211 {
1212 	struct apple_dart *dart = platform_get_drvdata(pdev);
1213 
1214 	apple_dart_hw_reset(dart);
1215 	free_irq(dart->irq, dart);
1216 
1217 	iommu_device_unregister(&dart->iommu);
1218 	iommu_device_sysfs_remove(&dart->iommu);
1219 
1220 	clk_bulk_disable_unprepare(dart->num_clks, dart->clks);
1221 }
1222 
1223 static const struct apple_dart_hw apple_dart_hw_t8103 = {
1224 	.type = DART_T8020,
1225 	.irq_handler = apple_dart_t8020_irq,
1226 	.invalidate_tlb = apple_dart_t8020_hw_invalidate_tlb,
1227 	.oas = 36,
1228 	.fmt = APPLE_DART,
1229 	.max_sid_count = 16,
1230 
1231 	.enable_streams = DART_T8020_STREAMS_ENABLE,
1232 	.lock = DART_T8020_CONFIG,
1233 	.lock_bit = DART_T8020_CONFIG_LOCK,
1234 
1235 	.error = DART_T8020_ERROR,
1236 
1237 	.tcr = DART_T8020_TCR,
1238 	.tcr_enabled = DART_T8020_TCR_TRANSLATE_ENABLE,
1239 	.tcr_disabled = 0,
1240 	.tcr_bypass = DART_T8020_TCR_BYPASS_DAPF | DART_T8020_TCR_BYPASS_DART,
1241 
1242 	.ttbr = DART_T8020_TTBR,
1243 	.ttbr_valid = DART_T8020_TTBR_VALID,
1244 	.ttbr_addr_field_shift = DART_T8020_TTBR_ADDR_FIELD_SHIFT,
1245 	.ttbr_shift = DART_T8020_TTBR_SHIFT,
1246 	.ttbr_count = 4,
1247 };
1248 
1249 static const struct apple_dart_hw apple_dart_hw_t8103_usb4 = {
1250 	.type = DART_T8020,
1251 	.irq_handler = apple_dart_t8020_irq,
1252 	.invalidate_tlb = apple_dart_t8020_hw_invalidate_tlb,
1253 	.oas = 36,
1254 	.fmt = APPLE_DART,
1255 	.max_sid_count = 64,
1256 
1257 	.enable_streams = DART_T8020_STREAMS_ENABLE,
1258 	.lock = DART_T8020_CONFIG,
1259 	.lock_bit = DART_T8020_CONFIG_LOCK,
1260 
1261 	.error = DART_T8020_ERROR,
1262 
1263 	.tcr = DART_T8020_TCR,
1264 	.tcr_enabled = DART_T8020_TCR_TRANSLATE_ENABLE,
1265 	.tcr_disabled = 0,
1266 	.tcr_bypass = 0,
1267 
1268 	.ttbr = DART_T8020_USB4_TTBR,
1269 	.ttbr_valid = DART_T8020_TTBR_VALID,
1270 	.ttbr_addr_field_shift = DART_T8020_TTBR_ADDR_FIELD_SHIFT,
1271 	.ttbr_shift = DART_T8020_TTBR_SHIFT,
1272 	.ttbr_count = 4,
1273 };
1274 
1275 static const struct apple_dart_hw apple_dart_hw_t6000 = {
1276 	.type = DART_T6000,
1277 	.irq_handler = apple_dart_t8020_irq,
1278 	.invalidate_tlb = apple_dart_t8020_hw_invalidate_tlb,
1279 	.oas = 42,
1280 	.fmt = APPLE_DART2,
1281 	.max_sid_count = 16,
1282 
1283 	.enable_streams = DART_T8020_STREAMS_ENABLE,
1284 	.lock = DART_T8020_CONFIG,
1285 	.lock_bit = DART_T8020_CONFIG_LOCK,
1286 
1287 	.error = DART_T8020_ERROR,
1288 
1289 	.tcr = DART_T8020_TCR,
1290 	.tcr_enabled = DART_T8020_TCR_TRANSLATE_ENABLE,
1291 	.tcr_disabled = 0,
1292 	.tcr_bypass = DART_T8020_TCR_BYPASS_DAPF | DART_T8020_TCR_BYPASS_DART,
1293 
1294 	.ttbr = DART_T8020_TTBR,
1295 	.ttbr_valid = DART_T8020_TTBR_VALID,
1296 	.ttbr_addr_field_shift = DART_T8020_TTBR_ADDR_FIELD_SHIFT,
1297 	.ttbr_shift = DART_T8020_TTBR_SHIFT,
1298 	.ttbr_count = 4,
1299 };
1300 
1301 static const struct apple_dart_hw apple_dart_hw_t8110 = {
1302 	.type = DART_T8110,
1303 	.irq_handler = apple_dart_t8110_irq,
1304 	.invalidate_tlb = apple_dart_t8110_hw_invalidate_tlb,
1305 	.fmt = APPLE_DART2,
1306 	.max_sid_count = 256,
1307 
1308 	.enable_streams = DART_T8110_ENABLE_STREAMS,
1309 	.lock = DART_T8110_PROTECT,
1310 	.lock_bit = DART_T8110_PROTECT_TTBR_TCR,
1311 
1312 	.error = DART_T8110_ERROR,
1313 
1314 	.tcr = DART_T8110_TCR,
1315 	.tcr_enabled = DART_T8110_TCR_TRANSLATE_ENABLE,
1316 	.tcr_disabled = 0,
1317 	.tcr_bypass = DART_T8110_TCR_BYPASS_DAPF | DART_T8110_TCR_BYPASS_DART,
1318 	.tcr_4level = DART_T8110_TCR_FOUR_LEVEL,
1319 
1320 	.ttbr = DART_T8110_TTBR,
1321 	.ttbr_valid = DART_T8110_TTBR_VALID,
1322 	.ttbr_addr_field_shift = DART_T8110_TTBR_ADDR_FIELD_SHIFT,
1323 	.ttbr_shift = DART_T8110_TTBR_SHIFT,
1324 	.ttbr_count = 1,
1325 };
1326 
apple_dart_suspend(struct device * dev)1327 static __maybe_unused int apple_dart_suspend(struct device *dev)
1328 {
1329 	struct apple_dart *dart = dev_get_drvdata(dev);
1330 	unsigned int sid, idx;
1331 
1332 	for (sid = 0; sid < dart->num_streams; sid++) {
1333 		dart->save_tcr[sid] = readl(dart->regs + DART_TCR(dart, sid));
1334 		for (idx = 0; idx < dart->hw->ttbr_count; idx++)
1335 			dart->save_ttbr[sid][idx] =
1336 				readl(dart->regs + DART_TTBR(dart, sid, idx));
1337 	}
1338 
1339 	return 0;
1340 }
1341 
apple_dart_resume(struct device * dev)1342 static __maybe_unused int apple_dart_resume(struct device *dev)
1343 {
1344 	struct apple_dart *dart = dev_get_drvdata(dev);
1345 	unsigned int sid, idx;
1346 	int ret;
1347 
1348 	ret = apple_dart_hw_reset(dart);
1349 	if (ret) {
1350 		dev_err(dev, "Failed to reset DART on resume\n");
1351 		return ret;
1352 	}
1353 
1354 	for (sid = 0; sid < dart->num_streams; sid++) {
1355 		for (idx = 0; idx < dart->hw->ttbr_count; idx++)
1356 			writel(dart->save_ttbr[sid][idx],
1357 			       dart->regs + DART_TTBR(dart, sid, idx));
1358 		writel(dart->save_tcr[sid], dart->regs + DART_TCR(dart, sid));
1359 	}
1360 
1361 	return 0;
1362 }
1363 
1364 static DEFINE_SIMPLE_DEV_PM_OPS(apple_dart_pm_ops, apple_dart_suspend, apple_dart_resume);
1365 
1366 static const struct of_device_id apple_dart_of_match[] = {
1367 	{ .compatible = "apple,t8103-dart", .data = &apple_dart_hw_t8103 },
1368 	{ .compatible = "apple,t8103-usb4-dart", .data = &apple_dart_hw_t8103_usb4 },
1369 	{ .compatible = "apple,t8110-dart", .data = &apple_dart_hw_t8110 },
1370 	{ .compatible = "apple,t6000-dart", .data = &apple_dart_hw_t6000 },
1371 	{},
1372 };
1373 MODULE_DEVICE_TABLE(of, apple_dart_of_match);
1374 
1375 static struct platform_driver apple_dart_driver = {
1376 	.driver	= {
1377 		.name			= "apple-dart",
1378 		.of_match_table		= apple_dart_of_match,
1379 		.suppress_bind_attrs    = true,
1380 		.pm			= pm_sleep_ptr(&apple_dart_pm_ops),
1381 	},
1382 	.probe	= apple_dart_probe,
1383 	.remove = apple_dart_remove,
1384 };
1385 
1386 module_platform_driver(apple_dart_driver);
1387 
1388 MODULE_DESCRIPTION("IOMMU API for Apple's DART");
1389 MODULE_AUTHOR("Sven Peter <sven@svenpeter.dev>");
1390 MODULE_LICENSE("GPL v2");
1391