1 /*
2  * This program is free software; you can redistribute it and/or modify
3  * it under the terms of the GNU General Public License version 2 as
4  * published by the Free Software Foundation.
5  */
6 
7 #include <linux/clk.h>
8 #include <linux/compiler.h>
9 #include <linux/delay.h>
10 #include <linux/device.h>
11 #include <linux/dma-iommu.h>
12 #include <linux/dma-mapping.h>
13 #include <linux/errno.h>
14 #include <linux/interrupt.h>
15 #include <linux/io.h>
16 #include <linux/iommu.h>
17 #include <linux/iopoll.h>
18 #include <linux/list.h>
19 #include <linux/mm.h>
20 #include <linux/module.h>
21 #include <linux/of.h>
22 #include <linux/of_iommu.h>
23 #include <linux/of_platform.h>
24 #include <linux/platform_device.h>
25 #include <linux/pm_runtime.h>
26 #include <linux/slab.h>
27 #include <linux/spinlock.h>
28 
29 /** MMU register offsets */
30 #define RK_MMU_DTE_ADDR		0x00	/* Directory table address */
31 #define RK_MMU_STATUS		0x04
32 #define RK_MMU_COMMAND		0x08
33 #define RK_MMU_PAGE_FAULT_ADDR	0x0C	/* IOVA of last page fault */
34 #define RK_MMU_ZAP_ONE_LINE	0x10	/* Shootdown one IOTLB entry */
35 #define RK_MMU_INT_RAWSTAT	0x14	/* IRQ status ignoring mask */
36 #define RK_MMU_INT_CLEAR	0x18	/* Acknowledge and re-arm irq */
37 #define RK_MMU_INT_MASK		0x1C	/* IRQ enable */
38 #define RK_MMU_INT_STATUS	0x20	/* IRQ status after masking */
39 #define RK_MMU_AUTO_GATING	0x24
40 
41 #define DTE_ADDR_DUMMY		0xCAFEBABE
42 
43 #define RK_MMU_POLL_PERIOD_US		100
44 #define RK_MMU_FORCE_RESET_TIMEOUT_US	100000
45 #define RK_MMU_POLL_TIMEOUT_US		1000
46 
47 /* RK_MMU_STATUS fields */
48 #define RK_MMU_STATUS_PAGING_ENABLED       BIT(0)
49 #define RK_MMU_STATUS_PAGE_FAULT_ACTIVE    BIT(1)
50 #define RK_MMU_STATUS_STALL_ACTIVE         BIT(2)
51 #define RK_MMU_STATUS_IDLE                 BIT(3)
52 #define RK_MMU_STATUS_REPLAY_BUFFER_EMPTY  BIT(4)
53 #define RK_MMU_STATUS_PAGE_FAULT_IS_WRITE  BIT(5)
54 #define RK_MMU_STATUS_STALL_NOT_ACTIVE     BIT(31)
55 
56 /* RK_MMU_COMMAND command values */
57 #define RK_MMU_CMD_ENABLE_PAGING    0  /* Enable memory translation */
58 #define RK_MMU_CMD_DISABLE_PAGING   1  /* Disable memory translation */
59 #define RK_MMU_CMD_ENABLE_STALL     2  /* Stall paging to allow other cmds */
60 #define RK_MMU_CMD_DISABLE_STALL    3  /* Stop stall re-enables paging */
61 #define RK_MMU_CMD_ZAP_CACHE        4  /* Shoot down entire IOTLB */
62 #define RK_MMU_CMD_PAGE_FAULT_DONE  5  /* Clear page fault */
63 #define RK_MMU_CMD_FORCE_RESET      6  /* Reset all registers */
64 
65 /* RK_MMU_INT_* register fields */
66 #define RK_MMU_IRQ_PAGE_FAULT    0x01  /* page fault */
67 #define RK_MMU_IRQ_BUS_ERROR     0x02  /* bus read error */
68 #define RK_MMU_IRQ_MASK          (RK_MMU_IRQ_PAGE_FAULT | RK_MMU_IRQ_BUS_ERROR)
69 
70 #define NUM_DT_ENTRIES 1024
71 #define NUM_PT_ENTRIES 1024
72 
73 #define SPAGE_ORDER 12
74 #define SPAGE_SIZE (1 << SPAGE_ORDER)
75 
76  /*
77   * Support mapping any size that fits in one page table:
78   *   4 KiB to 4 MiB
79   */
80 #define RK_IOMMU_PGSIZE_BITMAP 0x007ff000
81 
82 struct rk_iommu_domain {
83 	struct list_head iommus;
84 	u32 *dt; /* page directory table */
85 	dma_addr_t dt_dma;
86 	spinlock_t iommus_lock; /* lock for iommus list */
87 	spinlock_t dt_lock; /* lock for modifying page directory table */
88 
89 	struct iommu_domain domain;
90 };
91 
92 /* list of clocks required by IOMMU */
93 static const char * const rk_iommu_clocks[] = {
94 	"aclk", "iface",
95 };
96 
97 struct rk_iommu {
98 	struct device *dev;
99 	void __iomem **bases;
100 	int num_mmu;
101 	struct clk_bulk_data *clocks;
102 	int num_clocks;
103 	bool reset_disabled;
104 	struct iommu_device iommu;
105 	struct list_head node; /* entry in rk_iommu_domain.iommus */
106 	struct iommu_domain *domain; /* domain to which iommu is attached */
107 	struct iommu_group *group;
108 };
109 
110 struct rk_iommudata {
111 	struct device_link *link; /* runtime PM link from IOMMU to master */
112 	struct rk_iommu *iommu;
113 };
114 
115 static struct device *dma_dev;
116 
117 static inline void rk_table_flush(struct rk_iommu_domain *dom, dma_addr_t dma,
118 				  unsigned int count)
119 {
120 	size_t size = count * sizeof(u32); /* count of u32 entry */
121 
122 	dma_sync_single_for_device(dma_dev, dma, size, DMA_TO_DEVICE);
123 }
124 
125 static struct rk_iommu_domain *to_rk_domain(struct iommu_domain *dom)
126 {
127 	return container_of(dom, struct rk_iommu_domain, domain);
128 }
129 
130 /*
131  * The Rockchip rk3288 iommu uses a 2-level page table.
132  * The first level is the "Directory Table" (DT).
133  * The DT consists of 1024 4-byte Directory Table Entries (DTEs), each pointing
134  * to a "Page Table".
135  * The second level is the 1024 Page Tables (PT).
136  * Each PT consists of 1024 4-byte Page Table Entries (PTEs), each pointing to
137  * a 4 KB page of physical memory.
138  *
139  * The DT and each PT fits in a single 4 KB page (4-bytes * 1024 entries).
140  * Each iommu device has a MMU_DTE_ADDR register that contains the physical
141  * address of the start of the DT page.
142  *
143  * The structure of the page table is as follows:
144  *
145  *                   DT
146  * MMU_DTE_ADDR -> +-----+
147  *                 |     |
148  *                 +-----+     PT
149  *                 | DTE | -> +-----+
150  *                 +-----+    |     |     Memory
151  *                 |     |    +-----+     Page
152  *                 |     |    | PTE | -> +-----+
153  *                 +-----+    +-----+    |     |
154  *                            |     |    |     |
155  *                            |     |    |     |
156  *                            +-----+    |     |
157  *                                       |     |
158  *                                       |     |
159  *                                       +-----+
160  */
161 
162 /*
163  * Each DTE has a PT address and a valid bit:
164  * +---------------------+-----------+-+
165  * | PT address          | Reserved  |V|
166  * +---------------------+-----------+-+
167  *  31:12 - PT address (PTs always starts on a 4 KB boundary)
168  *  11: 1 - Reserved
169  *      0 - 1 if PT @ PT address is valid
170  */
171 #define RK_DTE_PT_ADDRESS_MASK    0xfffff000
172 #define RK_DTE_PT_VALID           BIT(0)
173 
174 static inline phys_addr_t rk_dte_pt_address(u32 dte)
175 {
176 	return (phys_addr_t)dte & RK_DTE_PT_ADDRESS_MASK;
177 }
178 
179 static inline bool rk_dte_is_pt_valid(u32 dte)
180 {
181 	return dte & RK_DTE_PT_VALID;
182 }
183 
184 static inline u32 rk_mk_dte(dma_addr_t pt_dma)
185 {
186 	return (pt_dma & RK_DTE_PT_ADDRESS_MASK) | RK_DTE_PT_VALID;
187 }
188 
189 /*
190  * Each PTE has a Page address, some flags and a valid bit:
191  * +---------------------+---+-------+-+
192  * | Page address        |Rsv| Flags |V|
193  * +---------------------+---+-------+-+
194  *  31:12 - Page address (Pages always start on a 4 KB boundary)
195  *  11: 9 - Reserved
196  *   8: 1 - Flags
197  *      8 - Read allocate - allocate cache space on read misses
198  *      7 - Read cache - enable cache & prefetch of data
199  *      6 - Write buffer - enable delaying writes on their way to memory
200  *      5 - Write allocate - allocate cache space on write misses
201  *      4 - Write cache - different writes can be merged together
202  *      3 - Override cache attributes
203  *          if 1, bits 4-8 control cache attributes
204  *          if 0, the system bus defaults are used
205  *      2 - Writable
206  *      1 - Readable
207  *      0 - 1 if Page @ Page address is valid
208  */
209 #define RK_PTE_PAGE_ADDRESS_MASK  0xfffff000
210 #define RK_PTE_PAGE_FLAGS_MASK    0x000001fe
211 #define RK_PTE_PAGE_WRITABLE      BIT(2)
212 #define RK_PTE_PAGE_READABLE      BIT(1)
213 #define RK_PTE_PAGE_VALID         BIT(0)
214 
215 static inline phys_addr_t rk_pte_page_address(u32 pte)
216 {
217 	return (phys_addr_t)pte & RK_PTE_PAGE_ADDRESS_MASK;
218 }
219 
220 static inline bool rk_pte_is_page_valid(u32 pte)
221 {
222 	return pte & RK_PTE_PAGE_VALID;
223 }
224 
225 /* TODO: set cache flags per prot IOMMU_CACHE */
226 static u32 rk_mk_pte(phys_addr_t page, int prot)
227 {
228 	u32 flags = 0;
229 	flags |= (prot & IOMMU_READ) ? RK_PTE_PAGE_READABLE : 0;
230 	flags |= (prot & IOMMU_WRITE) ? RK_PTE_PAGE_WRITABLE : 0;
231 	page &= RK_PTE_PAGE_ADDRESS_MASK;
232 	return page | flags | RK_PTE_PAGE_VALID;
233 }
234 
235 static u32 rk_mk_pte_invalid(u32 pte)
236 {
237 	return pte & ~RK_PTE_PAGE_VALID;
238 }
239 
240 /*
241  * rk3288 iova (IOMMU Virtual Address) format
242  *  31       22.21       12.11          0
243  * +-----------+-----------+-------------+
244  * | DTE index | PTE index | Page offset |
245  * +-----------+-----------+-------------+
246  *  31:22 - DTE index   - index of DTE in DT
247  *  21:12 - PTE index   - index of PTE in PT @ DTE.pt_address
248  *  11: 0 - Page offset - offset into page @ PTE.page_address
249  */
250 #define RK_IOVA_DTE_MASK    0xffc00000
251 #define RK_IOVA_DTE_SHIFT   22
252 #define RK_IOVA_PTE_MASK    0x003ff000
253 #define RK_IOVA_PTE_SHIFT   12
254 #define RK_IOVA_PAGE_MASK   0x00000fff
255 #define RK_IOVA_PAGE_SHIFT  0
256 
257 static u32 rk_iova_dte_index(dma_addr_t iova)
258 {
259 	return (u32)(iova & RK_IOVA_DTE_MASK) >> RK_IOVA_DTE_SHIFT;
260 }
261 
262 static u32 rk_iova_pte_index(dma_addr_t iova)
263 {
264 	return (u32)(iova & RK_IOVA_PTE_MASK) >> RK_IOVA_PTE_SHIFT;
265 }
266 
267 static u32 rk_iova_page_offset(dma_addr_t iova)
268 {
269 	return (u32)(iova & RK_IOVA_PAGE_MASK) >> RK_IOVA_PAGE_SHIFT;
270 }
271 
272 static u32 rk_iommu_read(void __iomem *base, u32 offset)
273 {
274 	return readl(base + offset);
275 }
276 
277 static void rk_iommu_write(void __iomem *base, u32 offset, u32 value)
278 {
279 	writel(value, base + offset);
280 }
281 
282 static void rk_iommu_command(struct rk_iommu *iommu, u32 command)
283 {
284 	int i;
285 
286 	for (i = 0; i < iommu->num_mmu; i++)
287 		writel(command, iommu->bases[i] + RK_MMU_COMMAND);
288 }
289 
290 static void rk_iommu_base_command(void __iomem *base, u32 command)
291 {
292 	writel(command, base + RK_MMU_COMMAND);
293 }
294 static void rk_iommu_zap_lines(struct rk_iommu *iommu, dma_addr_t iova_start,
295 			       size_t size)
296 {
297 	int i;
298 	dma_addr_t iova_end = iova_start + size;
299 	/*
300 	 * TODO(djkurtz): Figure out when it is more efficient to shootdown the
301 	 * entire iotlb rather than iterate over individual iovas.
302 	 */
303 	for (i = 0; i < iommu->num_mmu; i++) {
304 		dma_addr_t iova;
305 
306 		for (iova = iova_start; iova < iova_end; iova += SPAGE_SIZE)
307 			rk_iommu_write(iommu->bases[i], RK_MMU_ZAP_ONE_LINE, iova);
308 	}
309 }
310 
311 static bool rk_iommu_is_stall_active(struct rk_iommu *iommu)
312 {
313 	bool active = true;
314 	int i;
315 
316 	for (i = 0; i < iommu->num_mmu; i++)
317 		active &= !!(rk_iommu_read(iommu->bases[i], RK_MMU_STATUS) &
318 					   RK_MMU_STATUS_STALL_ACTIVE);
319 
320 	return active;
321 }
322 
323 static bool rk_iommu_is_paging_enabled(struct rk_iommu *iommu)
324 {
325 	bool enable = true;
326 	int i;
327 
328 	for (i = 0; i < iommu->num_mmu; i++)
329 		enable &= !!(rk_iommu_read(iommu->bases[i], RK_MMU_STATUS) &
330 					   RK_MMU_STATUS_PAGING_ENABLED);
331 
332 	return enable;
333 }
334 
335 static bool rk_iommu_is_reset_done(struct rk_iommu *iommu)
336 {
337 	bool done = true;
338 	int i;
339 
340 	for (i = 0; i < iommu->num_mmu; i++)
341 		done &= rk_iommu_read(iommu->bases[i], RK_MMU_DTE_ADDR) == 0;
342 
343 	return done;
344 }
345 
346 static int rk_iommu_enable_stall(struct rk_iommu *iommu)
347 {
348 	int ret, i;
349 	bool val;
350 
351 	if (rk_iommu_is_stall_active(iommu))
352 		return 0;
353 
354 	/* Stall can only be enabled if paging is enabled */
355 	if (!rk_iommu_is_paging_enabled(iommu))
356 		return 0;
357 
358 	rk_iommu_command(iommu, RK_MMU_CMD_ENABLE_STALL);
359 
360 	ret = readx_poll_timeout(rk_iommu_is_stall_active, iommu, val,
361 				 val, RK_MMU_POLL_PERIOD_US,
362 				 RK_MMU_POLL_TIMEOUT_US);
363 	if (ret)
364 		for (i = 0; i < iommu->num_mmu; i++)
365 			dev_err(iommu->dev, "Enable stall request timed out, status: %#08x\n",
366 				rk_iommu_read(iommu->bases[i], RK_MMU_STATUS));
367 
368 	return ret;
369 }
370 
371 static int rk_iommu_disable_stall(struct rk_iommu *iommu)
372 {
373 	int ret, i;
374 	bool val;
375 
376 	if (!rk_iommu_is_stall_active(iommu))
377 		return 0;
378 
379 	rk_iommu_command(iommu, RK_MMU_CMD_DISABLE_STALL);
380 
381 	ret = readx_poll_timeout(rk_iommu_is_stall_active, iommu, val,
382 				 !val, RK_MMU_POLL_PERIOD_US,
383 				 RK_MMU_POLL_TIMEOUT_US);
384 	if (ret)
385 		for (i = 0; i < iommu->num_mmu; i++)
386 			dev_err(iommu->dev, "Disable stall request timed out, status: %#08x\n",
387 				rk_iommu_read(iommu->bases[i], RK_MMU_STATUS));
388 
389 	return ret;
390 }
391 
392 static int rk_iommu_enable_paging(struct rk_iommu *iommu)
393 {
394 	int ret, i;
395 	bool val;
396 
397 	if (rk_iommu_is_paging_enabled(iommu))
398 		return 0;
399 
400 	rk_iommu_command(iommu, RK_MMU_CMD_ENABLE_PAGING);
401 
402 	ret = readx_poll_timeout(rk_iommu_is_paging_enabled, iommu, val,
403 				 val, RK_MMU_POLL_PERIOD_US,
404 				 RK_MMU_POLL_TIMEOUT_US);
405 	if (ret)
406 		for (i = 0; i < iommu->num_mmu; i++)
407 			dev_err(iommu->dev, "Enable paging request timed out, status: %#08x\n",
408 				rk_iommu_read(iommu->bases[i], RK_MMU_STATUS));
409 
410 	return ret;
411 }
412 
413 static int rk_iommu_disable_paging(struct rk_iommu *iommu)
414 {
415 	int ret, i;
416 	bool val;
417 
418 	if (!rk_iommu_is_paging_enabled(iommu))
419 		return 0;
420 
421 	rk_iommu_command(iommu, RK_MMU_CMD_DISABLE_PAGING);
422 
423 	ret = readx_poll_timeout(rk_iommu_is_paging_enabled, iommu, val,
424 				 !val, RK_MMU_POLL_PERIOD_US,
425 				 RK_MMU_POLL_TIMEOUT_US);
426 	if (ret)
427 		for (i = 0; i < iommu->num_mmu; i++)
428 			dev_err(iommu->dev, "Disable paging request timed out, status: %#08x\n",
429 				rk_iommu_read(iommu->bases[i], RK_MMU_STATUS));
430 
431 	return ret;
432 }
433 
434 static int rk_iommu_force_reset(struct rk_iommu *iommu)
435 {
436 	int ret, i;
437 	u32 dte_addr;
438 	bool val;
439 
440 	if (iommu->reset_disabled)
441 		return 0;
442 
443 	/*
444 	 * Check if register DTE_ADDR is working by writing DTE_ADDR_DUMMY
445 	 * and verifying that upper 5 nybbles are read back.
446 	 */
447 	for (i = 0; i < iommu->num_mmu; i++) {
448 		rk_iommu_write(iommu->bases[i], RK_MMU_DTE_ADDR, DTE_ADDR_DUMMY);
449 
450 		dte_addr = rk_iommu_read(iommu->bases[i], RK_MMU_DTE_ADDR);
451 		if (dte_addr != (DTE_ADDR_DUMMY & RK_DTE_PT_ADDRESS_MASK)) {
452 			dev_err(iommu->dev, "Error during raw reset. MMU_DTE_ADDR is not functioning\n");
453 			return -EFAULT;
454 		}
455 	}
456 
457 	rk_iommu_command(iommu, RK_MMU_CMD_FORCE_RESET);
458 
459 	ret = readx_poll_timeout(rk_iommu_is_reset_done, iommu, val,
460 				 val, RK_MMU_FORCE_RESET_TIMEOUT_US,
461 				 RK_MMU_POLL_TIMEOUT_US);
462 	if (ret) {
463 		dev_err(iommu->dev, "FORCE_RESET command timed out\n");
464 		return ret;
465 	}
466 
467 	return 0;
468 }
469 
470 static void log_iova(struct rk_iommu *iommu, int index, dma_addr_t iova)
471 {
472 	void __iomem *base = iommu->bases[index];
473 	u32 dte_index, pte_index, page_offset;
474 	u32 mmu_dte_addr;
475 	phys_addr_t mmu_dte_addr_phys, dte_addr_phys;
476 	u32 *dte_addr;
477 	u32 dte;
478 	phys_addr_t pte_addr_phys = 0;
479 	u32 *pte_addr = NULL;
480 	u32 pte = 0;
481 	phys_addr_t page_addr_phys = 0;
482 	u32 page_flags = 0;
483 
484 	dte_index = rk_iova_dte_index(iova);
485 	pte_index = rk_iova_pte_index(iova);
486 	page_offset = rk_iova_page_offset(iova);
487 
488 	mmu_dte_addr = rk_iommu_read(base, RK_MMU_DTE_ADDR);
489 	mmu_dte_addr_phys = (phys_addr_t)mmu_dte_addr;
490 
491 	dte_addr_phys = mmu_dte_addr_phys + (4 * dte_index);
492 	dte_addr = phys_to_virt(dte_addr_phys);
493 	dte = *dte_addr;
494 
495 	if (!rk_dte_is_pt_valid(dte))
496 		goto print_it;
497 
498 	pte_addr_phys = rk_dte_pt_address(dte) + (pte_index * 4);
499 	pte_addr = phys_to_virt(pte_addr_phys);
500 	pte = *pte_addr;
501 
502 	if (!rk_pte_is_page_valid(pte))
503 		goto print_it;
504 
505 	page_addr_phys = rk_pte_page_address(pte) + page_offset;
506 	page_flags = pte & RK_PTE_PAGE_FLAGS_MASK;
507 
508 print_it:
509 	dev_err(iommu->dev, "iova = %pad: dte_index: %#03x pte_index: %#03x page_offset: %#03x\n",
510 		&iova, dte_index, pte_index, page_offset);
511 	dev_err(iommu->dev, "mmu_dte_addr: %pa dte@%pa: %#08x valid: %u pte@%pa: %#08x valid: %u page@%pa flags: %#03x\n",
512 		&mmu_dte_addr_phys, &dte_addr_phys, dte,
513 		rk_dte_is_pt_valid(dte), &pte_addr_phys, pte,
514 		rk_pte_is_page_valid(pte), &page_addr_phys, page_flags);
515 }
516 
517 static irqreturn_t rk_iommu_irq(int irq, void *dev_id)
518 {
519 	struct rk_iommu *iommu = dev_id;
520 	u32 status;
521 	u32 int_status;
522 	dma_addr_t iova;
523 	irqreturn_t ret = IRQ_NONE;
524 	int i;
525 
526 	if (WARN_ON(!pm_runtime_get_if_in_use(iommu->dev)))
527 		return 0;
528 
529 	if (WARN_ON(clk_bulk_enable(iommu->num_clocks, iommu->clocks)))
530 		goto out;
531 
532 	for (i = 0; i < iommu->num_mmu; i++) {
533 		int_status = rk_iommu_read(iommu->bases[i], RK_MMU_INT_STATUS);
534 		if (int_status == 0)
535 			continue;
536 
537 		ret = IRQ_HANDLED;
538 		iova = rk_iommu_read(iommu->bases[i], RK_MMU_PAGE_FAULT_ADDR);
539 
540 		if (int_status & RK_MMU_IRQ_PAGE_FAULT) {
541 			int flags;
542 
543 			status = rk_iommu_read(iommu->bases[i], RK_MMU_STATUS);
544 			flags = (status & RK_MMU_STATUS_PAGE_FAULT_IS_WRITE) ?
545 					IOMMU_FAULT_WRITE : IOMMU_FAULT_READ;
546 
547 			dev_err(iommu->dev, "Page fault at %pad of type %s\n",
548 				&iova,
549 				(flags == IOMMU_FAULT_WRITE) ? "write" : "read");
550 
551 			log_iova(iommu, i, iova);
552 
553 			/*
554 			 * Report page fault to any installed handlers.
555 			 * Ignore the return code, though, since we always zap cache
556 			 * and clear the page fault anyway.
557 			 */
558 			if (iommu->domain)
559 				report_iommu_fault(iommu->domain, iommu->dev, iova,
560 						   flags);
561 			else
562 				dev_err(iommu->dev, "Page fault while iommu not attached to domain?\n");
563 
564 			rk_iommu_base_command(iommu->bases[i], RK_MMU_CMD_ZAP_CACHE);
565 			rk_iommu_base_command(iommu->bases[i], RK_MMU_CMD_PAGE_FAULT_DONE);
566 		}
567 
568 		if (int_status & RK_MMU_IRQ_BUS_ERROR)
569 			dev_err(iommu->dev, "BUS_ERROR occurred at %pad\n", &iova);
570 
571 		if (int_status & ~RK_MMU_IRQ_MASK)
572 			dev_err(iommu->dev, "unexpected int_status: %#08x\n",
573 				int_status);
574 
575 		rk_iommu_write(iommu->bases[i], RK_MMU_INT_CLEAR, int_status);
576 	}
577 
578 	clk_bulk_disable(iommu->num_clocks, iommu->clocks);
579 
580 out:
581 	pm_runtime_put(iommu->dev);
582 	return ret;
583 }
584 
585 static phys_addr_t rk_iommu_iova_to_phys(struct iommu_domain *domain,
586 					 dma_addr_t iova)
587 {
588 	struct rk_iommu_domain *rk_domain = to_rk_domain(domain);
589 	unsigned long flags;
590 	phys_addr_t pt_phys, phys = 0;
591 	u32 dte, pte;
592 	u32 *page_table;
593 
594 	spin_lock_irqsave(&rk_domain->dt_lock, flags);
595 
596 	dte = rk_domain->dt[rk_iova_dte_index(iova)];
597 	if (!rk_dte_is_pt_valid(dte))
598 		goto out;
599 
600 	pt_phys = rk_dte_pt_address(dte);
601 	page_table = (u32 *)phys_to_virt(pt_phys);
602 	pte = page_table[rk_iova_pte_index(iova)];
603 	if (!rk_pte_is_page_valid(pte))
604 		goto out;
605 
606 	phys = rk_pte_page_address(pte) + rk_iova_page_offset(iova);
607 out:
608 	spin_unlock_irqrestore(&rk_domain->dt_lock, flags);
609 
610 	return phys;
611 }
612 
613 static void rk_iommu_zap_iova(struct rk_iommu_domain *rk_domain,
614 			      dma_addr_t iova, size_t size)
615 {
616 	struct list_head *pos;
617 	unsigned long flags;
618 
619 	/* shootdown these iova from all iommus using this domain */
620 	spin_lock_irqsave(&rk_domain->iommus_lock, flags);
621 	list_for_each(pos, &rk_domain->iommus) {
622 		struct rk_iommu *iommu;
623 
624 		iommu = list_entry(pos, struct rk_iommu, node);
625 
626 		/* Only zap TLBs of IOMMUs that are powered on. */
627 		if (pm_runtime_get_if_in_use(iommu->dev)) {
628 			WARN_ON(clk_bulk_enable(iommu->num_clocks,
629 						iommu->clocks));
630 			rk_iommu_zap_lines(iommu, iova, size);
631 			clk_bulk_disable(iommu->num_clocks, iommu->clocks);
632 			pm_runtime_put(iommu->dev);
633 		}
634 	}
635 	spin_unlock_irqrestore(&rk_domain->iommus_lock, flags);
636 }
637 
638 static void rk_iommu_zap_iova_first_last(struct rk_iommu_domain *rk_domain,
639 					 dma_addr_t iova, size_t size)
640 {
641 	rk_iommu_zap_iova(rk_domain, iova, SPAGE_SIZE);
642 	if (size > SPAGE_SIZE)
643 		rk_iommu_zap_iova(rk_domain, iova + size - SPAGE_SIZE,
644 					SPAGE_SIZE);
645 }
646 
647 static u32 *rk_dte_get_page_table(struct rk_iommu_domain *rk_domain,
648 				  dma_addr_t iova)
649 {
650 	u32 *page_table, *dte_addr;
651 	u32 dte_index, dte;
652 	phys_addr_t pt_phys;
653 	dma_addr_t pt_dma;
654 
655 	assert_spin_locked(&rk_domain->dt_lock);
656 
657 	dte_index = rk_iova_dte_index(iova);
658 	dte_addr = &rk_domain->dt[dte_index];
659 	dte = *dte_addr;
660 	if (rk_dte_is_pt_valid(dte))
661 		goto done;
662 
663 	page_table = (u32 *)get_zeroed_page(GFP_ATOMIC | GFP_DMA32);
664 	if (!page_table)
665 		return ERR_PTR(-ENOMEM);
666 
667 	pt_dma = dma_map_single(dma_dev, page_table, SPAGE_SIZE, DMA_TO_DEVICE);
668 	if (dma_mapping_error(dma_dev, pt_dma)) {
669 		dev_err(dma_dev, "DMA mapping error while allocating page table\n");
670 		free_page((unsigned long)page_table);
671 		return ERR_PTR(-ENOMEM);
672 	}
673 
674 	dte = rk_mk_dte(pt_dma);
675 	*dte_addr = dte;
676 
677 	rk_table_flush(rk_domain, pt_dma, NUM_PT_ENTRIES);
678 	rk_table_flush(rk_domain,
679 		       rk_domain->dt_dma + dte_index * sizeof(u32), 1);
680 done:
681 	pt_phys = rk_dte_pt_address(dte);
682 	return (u32 *)phys_to_virt(pt_phys);
683 }
684 
685 static size_t rk_iommu_unmap_iova(struct rk_iommu_domain *rk_domain,
686 				  u32 *pte_addr, dma_addr_t pte_dma,
687 				  size_t size)
688 {
689 	unsigned int pte_count;
690 	unsigned int pte_total = size / SPAGE_SIZE;
691 
692 	assert_spin_locked(&rk_domain->dt_lock);
693 
694 	for (pte_count = 0; pte_count < pte_total; pte_count++) {
695 		u32 pte = pte_addr[pte_count];
696 		if (!rk_pte_is_page_valid(pte))
697 			break;
698 
699 		pte_addr[pte_count] = rk_mk_pte_invalid(pte);
700 	}
701 
702 	rk_table_flush(rk_domain, pte_dma, pte_count);
703 
704 	return pte_count * SPAGE_SIZE;
705 }
706 
707 static int rk_iommu_map_iova(struct rk_iommu_domain *rk_domain, u32 *pte_addr,
708 			     dma_addr_t pte_dma, dma_addr_t iova,
709 			     phys_addr_t paddr, size_t size, int prot)
710 {
711 	unsigned int pte_count;
712 	unsigned int pte_total = size / SPAGE_SIZE;
713 	phys_addr_t page_phys;
714 
715 	assert_spin_locked(&rk_domain->dt_lock);
716 
717 	for (pte_count = 0; pte_count < pte_total; pte_count++) {
718 		u32 pte = pte_addr[pte_count];
719 
720 		if (rk_pte_is_page_valid(pte))
721 			goto unwind;
722 
723 		pte_addr[pte_count] = rk_mk_pte(paddr, prot);
724 
725 		paddr += SPAGE_SIZE;
726 	}
727 
728 	rk_table_flush(rk_domain, pte_dma, pte_total);
729 
730 	/*
731 	 * Zap the first and last iova to evict from iotlb any previously
732 	 * mapped cachelines holding stale values for its dte and pte.
733 	 * We only zap the first and last iova, since only they could have
734 	 * dte or pte shared with an existing mapping.
735 	 */
736 	rk_iommu_zap_iova_first_last(rk_domain, iova, size);
737 
738 	return 0;
739 unwind:
740 	/* Unmap the range of iovas that we just mapped */
741 	rk_iommu_unmap_iova(rk_domain, pte_addr, pte_dma,
742 			    pte_count * SPAGE_SIZE);
743 
744 	iova += pte_count * SPAGE_SIZE;
745 	page_phys = rk_pte_page_address(pte_addr[pte_count]);
746 	pr_err("iova: %pad already mapped to %pa cannot remap to phys: %pa prot: %#x\n",
747 	       &iova, &page_phys, &paddr, prot);
748 
749 	return -EADDRINUSE;
750 }
751 
752 static int rk_iommu_map(struct iommu_domain *domain, unsigned long _iova,
753 			phys_addr_t paddr, size_t size, int prot)
754 {
755 	struct rk_iommu_domain *rk_domain = to_rk_domain(domain);
756 	unsigned long flags;
757 	dma_addr_t pte_dma, iova = (dma_addr_t)_iova;
758 	u32 *page_table, *pte_addr;
759 	u32 dte_index, pte_index;
760 	int ret;
761 
762 	spin_lock_irqsave(&rk_domain->dt_lock, flags);
763 
764 	/*
765 	 * pgsize_bitmap specifies iova sizes that fit in one page table
766 	 * (1024 4-KiB pages = 4 MiB).
767 	 * So, size will always be 4096 <= size <= 4194304.
768 	 * Since iommu_map() guarantees that both iova and size will be
769 	 * aligned, we will always only be mapping from a single dte here.
770 	 */
771 	page_table = rk_dte_get_page_table(rk_domain, iova);
772 	if (IS_ERR(page_table)) {
773 		spin_unlock_irqrestore(&rk_domain->dt_lock, flags);
774 		return PTR_ERR(page_table);
775 	}
776 
777 	dte_index = rk_domain->dt[rk_iova_dte_index(iova)];
778 	pte_index = rk_iova_pte_index(iova);
779 	pte_addr = &page_table[pte_index];
780 	pte_dma = rk_dte_pt_address(dte_index) + pte_index * sizeof(u32);
781 	ret = rk_iommu_map_iova(rk_domain, pte_addr, pte_dma, iova,
782 				paddr, size, prot);
783 
784 	spin_unlock_irqrestore(&rk_domain->dt_lock, flags);
785 
786 	return ret;
787 }
788 
789 static size_t rk_iommu_unmap(struct iommu_domain *domain, unsigned long _iova,
790 			     size_t size)
791 {
792 	struct rk_iommu_domain *rk_domain = to_rk_domain(domain);
793 	unsigned long flags;
794 	dma_addr_t pte_dma, iova = (dma_addr_t)_iova;
795 	phys_addr_t pt_phys;
796 	u32 dte;
797 	u32 *pte_addr;
798 	size_t unmap_size;
799 
800 	spin_lock_irqsave(&rk_domain->dt_lock, flags);
801 
802 	/*
803 	 * pgsize_bitmap specifies iova sizes that fit in one page table
804 	 * (1024 4-KiB pages = 4 MiB).
805 	 * So, size will always be 4096 <= size <= 4194304.
806 	 * Since iommu_unmap() guarantees that both iova and size will be
807 	 * aligned, we will always only be unmapping from a single dte here.
808 	 */
809 	dte = rk_domain->dt[rk_iova_dte_index(iova)];
810 	/* Just return 0 if iova is unmapped */
811 	if (!rk_dte_is_pt_valid(dte)) {
812 		spin_unlock_irqrestore(&rk_domain->dt_lock, flags);
813 		return 0;
814 	}
815 
816 	pt_phys = rk_dte_pt_address(dte);
817 	pte_addr = (u32 *)phys_to_virt(pt_phys) + rk_iova_pte_index(iova);
818 	pte_dma = pt_phys + rk_iova_pte_index(iova) * sizeof(u32);
819 	unmap_size = rk_iommu_unmap_iova(rk_domain, pte_addr, pte_dma, size);
820 
821 	spin_unlock_irqrestore(&rk_domain->dt_lock, flags);
822 
823 	/* Shootdown iotlb entries for iova range that was just unmapped */
824 	rk_iommu_zap_iova(rk_domain, iova, unmap_size);
825 
826 	return unmap_size;
827 }
828 
829 static struct rk_iommu *rk_iommu_from_dev(struct device *dev)
830 {
831 	struct rk_iommudata *data = dev->archdata.iommu;
832 
833 	return data ? data->iommu : NULL;
834 }
835 
836 /* Must be called with iommu powered on and attached */
837 static void rk_iommu_disable(struct rk_iommu *iommu)
838 {
839 	int i;
840 
841 	/* Ignore error while disabling, just keep going */
842 	WARN_ON(clk_bulk_enable(iommu->num_clocks, iommu->clocks));
843 	rk_iommu_enable_stall(iommu);
844 	rk_iommu_disable_paging(iommu);
845 	for (i = 0; i < iommu->num_mmu; i++) {
846 		rk_iommu_write(iommu->bases[i], RK_MMU_INT_MASK, 0);
847 		rk_iommu_write(iommu->bases[i], RK_MMU_DTE_ADDR, 0);
848 	}
849 	rk_iommu_disable_stall(iommu);
850 	clk_bulk_disable(iommu->num_clocks, iommu->clocks);
851 }
852 
853 /* Must be called with iommu powered on and attached */
854 static int rk_iommu_enable(struct rk_iommu *iommu)
855 {
856 	struct iommu_domain *domain = iommu->domain;
857 	struct rk_iommu_domain *rk_domain = to_rk_domain(domain);
858 	int ret, i;
859 
860 	ret = clk_bulk_enable(iommu->num_clocks, iommu->clocks);
861 	if (ret)
862 		return ret;
863 
864 	ret = rk_iommu_enable_stall(iommu);
865 	if (ret)
866 		goto out_disable_clocks;
867 
868 	ret = rk_iommu_force_reset(iommu);
869 	if (ret)
870 		goto out_disable_stall;
871 
872 	for (i = 0; i < iommu->num_mmu; i++) {
873 		rk_iommu_write(iommu->bases[i], RK_MMU_DTE_ADDR,
874 			       rk_domain->dt_dma);
875 		rk_iommu_base_command(iommu->bases[i], RK_MMU_CMD_ZAP_CACHE);
876 		rk_iommu_write(iommu->bases[i], RK_MMU_INT_MASK, RK_MMU_IRQ_MASK);
877 	}
878 
879 	ret = rk_iommu_enable_paging(iommu);
880 
881 out_disable_stall:
882 	rk_iommu_disable_stall(iommu);
883 out_disable_clocks:
884 	clk_bulk_disable(iommu->num_clocks, iommu->clocks);
885 	return ret;
886 }
887 
888 static void rk_iommu_detach_device(struct iommu_domain *domain,
889 				   struct device *dev)
890 {
891 	struct rk_iommu *iommu;
892 	struct rk_iommu_domain *rk_domain = to_rk_domain(domain);
893 	unsigned long flags;
894 
895 	/* Allow 'virtual devices' (eg drm) to detach from domain */
896 	iommu = rk_iommu_from_dev(dev);
897 	if (!iommu)
898 		return;
899 
900 	dev_dbg(dev, "Detaching from iommu domain\n");
901 
902 	/* iommu already detached */
903 	if (iommu->domain != domain)
904 		return;
905 
906 	iommu->domain = NULL;
907 
908 	spin_lock_irqsave(&rk_domain->iommus_lock, flags);
909 	list_del_init(&iommu->node);
910 	spin_unlock_irqrestore(&rk_domain->iommus_lock, flags);
911 
912 	if (pm_runtime_get_if_in_use(iommu->dev)) {
913 		rk_iommu_disable(iommu);
914 		pm_runtime_put(iommu->dev);
915 	}
916 }
917 
918 static int rk_iommu_attach_device(struct iommu_domain *domain,
919 		struct device *dev)
920 {
921 	struct rk_iommu *iommu;
922 	struct rk_iommu_domain *rk_domain = to_rk_domain(domain);
923 	unsigned long flags;
924 	int ret;
925 
926 	/*
927 	 * Allow 'virtual devices' (e.g., drm) to attach to domain.
928 	 * Such a device does not belong to an iommu group.
929 	 */
930 	iommu = rk_iommu_from_dev(dev);
931 	if (!iommu)
932 		return 0;
933 
934 	dev_dbg(dev, "Attaching to iommu domain\n");
935 
936 	/* iommu already attached */
937 	if (iommu->domain == domain)
938 		return 0;
939 
940 	if (iommu->domain)
941 		rk_iommu_detach_device(iommu->domain, dev);
942 
943 	iommu->domain = domain;
944 
945 	spin_lock_irqsave(&rk_domain->iommus_lock, flags);
946 	list_add_tail(&iommu->node, &rk_domain->iommus);
947 	spin_unlock_irqrestore(&rk_domain->iommus_lock, flags);
948 
949 	if (!pm_runtime_get_if_in_use(iommu->dev))
950 		return 0;
951 
952 	ret = rk_iommu_enable(iommu);
953 	if (ret)
954 		rk_iommu_detach_device(iommu->domain, dev);
955 
956 	pm_runtime_put(iommu->dev);
957 
958 	return ret;
959 }
960 
961 static struct iommu_domain *rk_iommu_domain_alloc(unsigned type)
962 {
963 	struct rk_iommu_domain *rk_domain;
964 
965 	if (type != IOMMU_DOMAIN_UNMANAGED && type != IOMMU_DOMAIN_DMA)
966 		return NULL;
967 
968 	if (!dma_dev)
969 		return NULL;
970 
971 	rk_domain = devm_kzalloc(dma_dev, sizeof(*rk_domain), GFP_KERNEL);
972 	if (!rk_domain)
973 		return NULL;
974 
975 	if (type == IOMMU_DOMAIN_DMA &&
976 	    iommu_get_dma_cookie(&rk_domain->domain))
977 		return NULL;
978 
979 	/*
980 	 * rk32xx iommus use a 2 level pagetable.
981 	 * Each level1 (dt) and level2 (pt) table has 1024 4-byte entries.
982 	 * Allocate one 4 KiB page for each table.
983 	 */
984 	rk_domain->dt = (u32 *)get_zeroed_page(GFP_KERNEL | GFP_DMA32);
985 	if (!rk_domain->dt)
986 		goto err_put_cookie;
987 
988 	rk_domain->dt_dma = dma_map_single(dma_dev, rk_domain->dt,
989 					   SPAGE_SIZE, DMA_TO_DEVICE);
990 	if (dma_mapping_error(dma_dev, rk_domain->dt_dma)) {
991 		dev_err(dma_dev, "DMA map error for DT\n");
992 		goto err_free_dt;
993 	}
994 
995 	rk_table_flush(rk_domain, rk_domain->dt_dma, NUM_DT_ENTRIES);
996 
997 	spin_lock_init(&rk_domain->iommus_lock);
998 	spin_lock_init(&rk_domain->dt_lock);
999 	INIT_LIST_HEAD(&rk_domain->iommus);
1000 
1001 	rk_domain->domain.geometry.aperture_start = 0;
1002 	rk_domain->domain.geometry.aperture_end   = DMA_BIT_MASK(32);
1003 	rk_domain->domain.geometry.force_aperture = true;
1004 
1005 	return &rk_domain->domain;
1006 
1007 err_free_dt:
1008 	free_page((unsigned long)rk_domain->dt);
1009 err_put_cookie:
1010 	if (type == IOMMU_DOMAIN_DMA)
1011 		iommu_put_dma_cookie(&rk_domain->domain);
1012 
1013 	return NULL;
1014 }
1015 
1016 static void rk_iommu_domain_free(struct iommu_domain *domain)
1017 {
1018 	struct rk_iommu_domain *rk_domain = to_rk_domain(domain);
1019 	int i;
1020 
1021 	WARN_ON(!list_empty(&rk_domain->iommus));
1022 
1023 	for (i = 0; i < NUM_DT_ENTRIES; i++) {
1024 		u32 dte = rk_domain->dt[i];
1025 		if (rk_dte_is_pt_valid(dte)) {
1026 			phys_addr_t pt_phys = rk_dte_pt_address(dte);
1027 			u32 *page_table = phys_to_virt(pt_phys);
1028 			dma_unmap_single(dma_dev, pt_phys,
1029 					 SPAGE_SIZE, DMA_TO_DEVICE);
1030 			free_page((unsigned long)page_table);
1031 		}
1032 	}
1033 
1034 	dma_unmap_single(dma_dev, rk_domain->dt_dma,
1035 			 SPAGE_SIZE, DMA_TO_DEVICE);
1036 	free_page((unsigned long)rk_domain->dt);
1037 
1038 	if (domain->type == IOMMU_DOMAIN_DMA)
1039 		iommu_put_dma_cookie(&rk_domain->domain);
1040 }
1041 
1042 static int rk_iommu_add_device(struct device *dev)
1043 {
1044 	struct iommu_group *group;
1045 	struct rk_iommu *iommu;
1046 	struct rk_iommudata *data;
1047 
1048 	data = dev->archdata.iommu;
1049 	if (!data)
1050 		return -ENODEV;
1051 
1052 	iommu = rk_iommu_from_dev(dev);
1053 
1054 	group = iommu_group_get_for_dev(dev);
1055 	if (IS_ERR(group))
1056 		return PTR_ERR(group);
1057 	iommu_group_put(group);
1058 
1059 	iommu_device_link(&iommu->iommu, dev);
1060 	data->link = device_link_add(dev, iommu->dev, DL_FLAG_PM_RUNTIME);
1061 
1062 	return 0;
1063 }
1064 
1065 static void rk_iommu_remove_device(struct device *dev)
1066 {
1067 	struct rk_iommu *iommu;
1068 	struct rk_iommudata *data = dev->archdata.iommu;
1069 
1070 	iommu = rk_iommu_from_dev(dev);
1071 
1072 	device_link_del(data->link);
1073 	iommu_device_unlink(&iommu->iommu, dev);
1074 	iommu_group_remove_device(dev);
1075 }
1076 
1077 static struct iommu_group *rk_iommu_device_group(struct device *dev)
1078 {
1079 	struct rk_iommu *iommu;
1080 
1081 	iommu = rk_iommu_from_dev(dev);
1082 
1083 	return iommu_group_ref_get(iommu->group);
1084 }
1085 
1086 static int rk_iommu_of_xlate(struct device *dev,
1087 			     struct of_phandle_args *args)
1088 {
1089 	struct platform_device *iommu_dev;
1090 	struct rk_iommudata *data;
1091 
1092 	data = devm_kzalloc(dma_dev, sizeof(*data), GFP_KERNEL);
1093 	if (!data)
1094 		return -ENOMEM;
1095 
1096 	iommu_dev = of_find_device_by_node(args->np);
1097 
1098 	data->iommu = platform_get_drvdata(iommu_dev);
1099 	dev->archdata.iommu = data;
1100 
1101 	platform_device_put(iommu_dev);
1102 
1103 	return 0;
1104 }
1105 
1106 static const struct iommu_ops rk_iommu_ops = {
1107 	.domain_alloc = rk_iommu_domain_alloc,
1108 	.domain_free = rk_iommu_domain_free,
1109 	.attach_dev = rk_iommu_attach_device,
1110 	.detach_dev = rk_iommu_detach_device,
1111 	.map = rk_iommu_map,
1112 	.unmap = rk_iommu_unmap,
1113 	.map_sg = default_iommu_map_sg,
1114 	.add_device = rk_iommu_add_device,
1115 	.remove_device = rk_iommu_remove_device,
1116 	.iova_to_phys = rk_iommu_iova_to_phys,
1117 	.device_group = rk_iommu_device_group,
1118 	.pgsize_bitmap = RK_IOMMU_PGSIZE_BITMAP,
1119 	.of_xlate = rk_iommu_of_xlate,
1120 };
1121 
1122 static int rk_iommu_probe(struct platform_device *pdev)
1123 {
1124 	struct device *dev = &pdev->dev;
1125 	struct rk_iommu *iommu;
1126 	struct resource *res;
1127 	int num_res = pdev->num_resources;
1128 	int err, i, irq;
1129 
1130 	iommu = devm_kzalloc(dev, sizeof(*iommu), GFP_KERNEL);
1131 	if (!iommu)
1132 		return -ENOMEM;
1133 
1134 	platform_set_drvdata(pdev, iommu);
1135 	iommu->dev = dev;
1136 	iommu->num_mmu = 0;
1137 
1138 	iommu->bases = devm_kcalloc(dev, num_res, sizeof(*iommu->bases),
1139 				    GFP_KERNEL);
1140 	if (!iommu->bases)
1141 		return -ENOMEM;
1142 
1143 	for (i = 0; i < num_res; i++) {
1144 		res = platform_get_resource(pdev, IORESOURCE_MEM, i);
1145 		if (!res)
1146 			continue;
1147 		iommu->bases[i] = devm_ioremap_resource(&pdev->dev, res);
1148 		if (IS_ERR(iommu->bases[i]))
1149 			continue;
1150 		iommu->num_mmu++;
1151 	}
1152 	if (iommu->num_mmu == 0)
1153 		return PTR_ERR(iommu->bases[0]);
1154 
1155 	i = 0;
1156 	while ((irq = platform_get_irq(pdev, i++)) != -ENXIO) {
1157 		if (irq < 0)
1158 			return irq;
1159 
1160 		err = devm_request_irq(iommu->dev, irq, rk_iommu_irq,
1161 				       IRQF_SHARED, dev_name(dev), iommu);
1162 		if (err)
1163 			return err;
1164 	}
1165 
1166 	iommu->reset_disabled = device_property_read_bool(dev,
1167 					"rockchip,disable-mmu-reset");
1168 
1169 	iommu->num_clocks = ARRAY_SIZE(rk_iommu_clocks);
1170 	iommu->clocks = devm_kcalloc(iommu->dev, iommu->num_clocks,
1171 				     sizeof(*iommu->clocks), GFP_KERNEL);
1172 	if (!iommu->clocks)
1173 		return -ENOMEM;
1174 
1175 	for (i = 0; i < iommu->num_clocks; ++i)
1176 		iommu->clocks[i].id = rk_iommu_clocks[i];
1177 
1178 	/*
1179 	 * iommu clocks should be present for all new devices and devicetrees
1180 	 * but there are older devicetrees without clocks out in the wild.
1181 	 * So clocks as optional for the time being.
1182 	 */
1183 	err = devm_clk_bulk_get(iommu->dev, iommu->num_clocks, iommu->clocks);
1184 	if (err == -ENOENT)
1185 		iommu->num_clocks = 0;
1186 	else if (err)
1187 		return err;
1188 
1189 	err = clk_bulk_prepare(iommu->num_clocks, iommu->clocks);
1190 	if (err)
1191 		return err;
1192 
1193 	iommu->group = iommu_group_alloc();
1194 	if (IS_ERR(iommu->group)) {
1195 		err = PTR_ERR(iommu->group);
1196 		goto err_unprepare_clocks;
1197 	}
1198 
1199 	err = iommu_device_sysfs_add(&iommu->iommu, dev, NULL, dev_name(dev));
1200 	if (err)
1201 		goto err_put_group;
1202 
1203 	iommu_device_set_ops(&iommu->iommu, &rk_iommu_ops);
1204 	iommu_device_set_fwnode(&iommu->iommu, &dev->of_node->fwnode);
1205 
1206 	err = iommu_device_register(&iommu->iommu);
1207 	if (err)
1208 		goto err_remove_sysfs;
1209 
1210 	/*
1211 	 * Use the first registered IOMMU device for domain to use with DMA
1212 	 * API, since a domain might not physically correspond to a single
1213 	 * IOMMU device..
1214 	 */
1215 	if (!dma_dev)
1216 		dma_dev = &pdev->dev;
1217 
1218 	bus_set_iommu(&platform_bus_type, &rk_iommu_ops);
1219 
1220 	pm_runtime_enable(dev);
1221 
1222 	return 0;
1223 err_remove_sysfs:
1224 	iommu_device_sysfs_remove(&iommu->iommu);
1225 err_put_group:
1226 	iommu_group_put(iommu->group);
1227 err_unprepare_clocks:
1228 	clk_bulk_unprepare(iommu->num_clocks, iommu->clocks);
1229 	return err;
1230 }
1231 
1232 static void rk_iommu_shutdown(struct platform_device *pdev)
1233 {
1234 	pm_runtime_force_suspend(&pdev->dev);
1235 }
1236 
1237 static int __maybe_unused rk_iommu_suspend(struct device *dev)
1238 {
1239 	struct rk_iommu *iommu = dev_get_drvdata(dev);
1240 
1241 	if (!iommu->domain)
1242 		return 0;
1243 
1244 	rk_iommu_disable(iommu);
1245 	return 0;
1246 }
1247 
1248 static int __maybe_unused rk_iommu_resume(struct device *dev)
1249 {
1250 	struct rk_iommu *iommu = dev_get_drvdata(dev);
1251 
1252 	if (!iommu->domain)
1253 		return 0;
1254 
1255 	return rk_iommu_enable(iommu);
1256 }
1257 
1258 static const struct dev_pm_ops rk_iommu_pm_ops = {
1259 	SET_RUNTIME_PM_OPS(rk_iommu_suspend, rk_iommu_resume, NULL)
1260 	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
1261 				pm_runtime_force_resume)
1262 };
1263 
1264 static const struct of_device_id rk_iommu_dt_ids[] = {
1265 	{ .compatible = "rockchip,iommu" },
1266 	{ /* sentinel */ }
1267 };
1268 MODULE_DEVICE_TABLE(of, rk_iommu_dt_ids);
1269 
1270 static struct platform_driver rk_iommu_driver = {
1271 	.probe = rk_iommu_probe,
1272 	.shutdown = rk_iommu_shutdown,
1273 	.driver = {
1274 		   .name = "rk_iommu",
1275 		   .of_match_table = rk_iommu_dt_ids,
1276 		   .pm = &rk_iommu_pm_ops,
1277 		   .suppress_bind_attrs = true,
1278 	},
1279 };
1280 
1281 static int __init rk_iommu_init(void)
1282 {
1283 	return platform_driver_register(&rk_iommu_driver);
1284 }
1285 subsys_initcall(rk_iommu_init);
1286 
1287 IOMMU_OF_DECLARE(rk_iommu_of, "rockchip,iommu");
1288 
1289 MODULE_DESCRIPTION("IOMMU API for Rockchip");
1290 MODULE_AUTHOR("Simon Xue <xxm@rock-chips.com> and Daniel Kurtz <djkurtz@chromium.org>");
1291 MODULE_ALIAS("platform:rockchip-iommu");
1292 MODULE_LICENSE("GPL v2");
1293