1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * IOMMU API for Rockchip
4  *
5  * Module Authors:	Simon Xue <xxm@rock-chips.com>
6  *			Daniel Kurtz <djkurtz@chromium.org>
7  */
8 
9 #include <linux/clk.h>
10 #include <linux/compiler.h>
11 #include <linux/delay.h>
12 #include <linux/device.h>
13 #include <linux/dma-mapping.h>
14 #include <linux/errno.h>
15 #include <linux/interrupt.h>
16 #include <linux/io.h>
17 #include <linux/iommu.h>
18 #include <linux/iopoll.h>
19 #include <linux/list.h>
20 #include <linux/mm.h>
21 #include <linux/init.h>
22 #include <linux/of.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_ops {
98 	phys_addr_t (*pt_address)(u32 dte);
99 	u32 (*mk_dtentries)(dma_addr_t pt_dma);
100 	u32 (*mk_ptentries)(phys_addr_t page, int prot);
101 	u64 dma_bit_mask;
102 	gfp_t gfp_flags;
103 };
104 
105 struct rk_iommu {
106 	struct device *dev;
107 	void __iomem **bases;
108 	int num_mmu;
109 	int num_irq;
110 	struct clk_bulk_data *clocks;
111 	int num_clocks;
112 	bool reset_disabled;
113 	struct iommu_device iommu;
114 	struct list_head node; /* entry in rk_iommu_domain.iommus */
115 	struct iommu_domain *domain; /* domain to which iommu is attached */
116 	struct iommu_group *group;
117 };
118 
119 struct rk_iommudata {
120 	struct device_link *link; /* runtime PM link from IOMMU to master */
121 	struct rk_iommu *iommu;
122 };
123 
124 static struct device *dma_dev;
125 static const struct rk_iommu_ops *rk_ops;
126 static struct iommu_domain rk_identity_domain;
127 
rk_table_flush(struct rk_iommu_domain * dom,dma_addr_t dma,unsigned int count)128 static inline void rk_table_flush(struct rk_iommu_domain *dom, dma_addr_t dma,
129 				  unsigned int count)
130 {
131 	size_t size = count * sizeof(u32); /* count of u32 entry */
132 
133 	dma_sync_single_for_device(dma_dev, dma, size, DMA_TO_DEVICE);
134 }
135 
to_rk_domain(struct iommu_domain * dom)136 static struct rk_iommu_domain *to_rk_domain(struct iommu_domain *dom)
137 {
138 	return container_of(dom, struct rk_iommu_domain, domain);
139 }
140 
141 /*
142  * The Rockchip rk3288 iommu uses a 2-level page table.
143  * The first level is the "Directory Table" (DT).
144  * The DT consists of 1024 4-byte Directory Table Entries (DTEs), each pointing
145  * to a "Page Table".
146  * The second level is the 1024 Page Tables (PT).
147  * Each PT consists of 1024 4-byte Page Table Entries (PTEs), each pointing to
148  * a 4 KB page of physical memory.
149  *
150  * The DT and each PT fits in a single 4 KB page (4-bytes * 1024 entries).
151  * Each iommu device has a MMU_DTE_ADDR register that contains the physical
152  * address of the start of the DT page.
153  *
154  * The structure of the page table is as follows:
155  *
156  *                   DT
157  * MMU_DTE_ADDR -> +-----+
158  *                 |     |
159  *                 +-----+     PT
160  *                 | DTE | -> +-----+
161  *                 +-----+    |     |     Memory
162  *                 |     |    +-----+     Page
163  *                 |     |    | PTE | -> +-----+
164  *                 +-----+    +-----+    |     |
165  *                            |     |    |     |
166  *                            |     |    |     |
167  *                            +-----+    |     |
168  *                                       |     |
169  *                                       |     |
170  *                                       +-----+
171  */
172 
173 /*
174  * Each DTE has a PT address and a valid bit:
175  * +---------------------+-----------+-+
176  * | PT address          | Reserved  |V|
177  * +---------------------+-----------+-+
178  *  31:12 - PT address (PTs always starts on a 4 KB boundary)
179  *  11: 1 - Reserved
180  *      0 - 1 if PT @ PT address is valid
181  */
182 #define RK_DTE_PT_ADDRESS_MASK    0xfffff000
183 #define RK_DTE_PT_VALID           BIT(0)
184 
rk_dte_pt_address(u32 dte)185 static inline phys_addr_t rk_dte_pt_address(u32 dte)
186 {
187 	return (phys_addr_t)dte & RK_DTE_PT_ADDRESS_MASK;
188 }
189 
190 /*
191  * In v2:
192  * 31:12 - PT address bit 31:0
193  * 11: 8 - PT address bit 35:32
194  *  7: 4 - PT address bit 39:36
195  *  3: 1 - Reserved
196  *     0 - 1 if PT @ PT address is valid
197  */
198 #define RK_DTE_PT_ADDRESS_MASK_V2 GENMASK_ULL(31, 4)
199 #define DTE_HI_MASK1	GENMASK(11, 8)
200 #define DTE_HI_MASK2	GENMASK(7, 4)
201 #define DTE_HI_SHIFT1	24 /* shift bit 8 to bit 32 */
202 #define DTE_HI_SHIFT2	32 /* shift bit 4 to bit 36 */
203 #define PAGE_DESC_HI_MASK1	GENMASK_ULL(35, 32)
204 #define PAGE_DESC_HI_MASK2	GENMASK_ULL(39, 36)
205 
rk_dte_pt_address_v2(u32 dte)206 static inline phys_addr_t rk_dte_pt_address_v2(u32 dte)
207 {
208 	u64 dte_v2 = dte;
209 
210 	dte_v2 = ((dte_v2 & DTE_HI_MASK2) << DTE_HI_SHIFT2) |
211 		 ((dte_v2 & DTE_HI_MASK1) << DTE_HI_SHIFT1) |
212 		 (dte_v2 & RK_DTE_PT_ADDRESS_MASK);
213 
214 	return (phys_addr_t)dte_v2;
215 }
216 
rk_dte_is_pt_valid(u32 dte)217 static inline bool rk_dte_is_pt_valid(u32 dte)
218 {
219 	return dte & RK_DTE_PT_VALID;
220 }
221 
rk_mk_dte(dma_addr_t pt_dma)222 static inline u32 rk_mk_dte(dma_addr_t pt_dma)
223 {
224 	return (pt_dma & RK_DTE_PT_ADDRESS_MASK) | RK_DTE_PT_VALID;
225 }
226 
rk_mk_dte_v2(dma_addr_t pt_dma)227 static inline u32 rk_mk_dte_v2(dma_addr_t pt_dma)
228 {
229 	pt_dma = (pt_dma & RK_DTE_PT_ADDRESS_MASK) |
230 		 ((pt_dma & PAGE_DESC_HI_MASK1) >> DTE_HI_SHIFT1) |
231 		 (pt_dma & PAGE_DESC_HI_MASK2) >> DTE_HI_SHIFT2;
232 
233 	return (pt_dma & RK_DTE_PT_ADDRESS_MASK_V2) | RK_DTE_PT_VALID;
234 }
235 
236 /*
237  * Each PTE has a Page address, some flags and a valid bit:
238  * +---------------------+---+-------+-+
239  * | Page address        |Rsv| Flags |V|
240  * +---------------------+---+-------+-+
241  *  31:12 - Page address (Pages always start on a 4 KB boundary)
242  *  11: 9 - Reserved
243  *   8: 1 - Flags
244  *      8 - Read allocate - allocate cache space on read misses
245  *      7 - Read cache - enable cache & prefetch of data
246  *      6 - Write buffer - enable delaying writes on their way to memory
247  *      5 - Write allocate - allocate cache space on write misses
248  *      4 - Write cache - different writes can be merged together
249  *      3 - Override cache attributes
250  *          if 1, bits 4-8 control cache attributes
251  *          if 0, the system bus defaults are used
252  *      2 - Writable
253  *      1 - Readable
254  *      0 - 1 if Page @ Page address is valid
255  */
256 #define RK_PTE_PAGE_ADDRESS_MASK  0xfffff000
257 #define RK_PTE_PAGE_FLAGS_MASK    0x000001fe
258 #define RK_PTE_PAGE_WRITABLE      BIT(2)
259 #define RK_PTE_PAGE_READABLE      BIT(1)
260 #define RK_PTE_PAGE_VALID         BIT(0)
261 
rk_pte_is_page_valid(u32 pte)262 static inline bool rk_pte_is_page_valid(u32 pte)
263 {
264 	return pte & RK_PTE_PAGE_VALID;
265 }
266 
267 /* TODO: set cache flags per prot IOMMU_CACHE */
rk_mk_pte(phys_addr_t page,int prot)268 static u32 rk_mk_pte(phys_addr_t page, int prot)
269 {
270 	u32 flags = 0;
271 	flags |= (prot & IOMMU_READ) ? RK_PTE_PAGE_READABLE : 0;
272 	flags |= (prot & IOMMU_WRITE) ? RK_PTE_PAGE_WRITABLE : 0;
273 	page &= RK_PTE_PAGE_ADDRESS_MASK;
274 	return page | flags | RK_PTE_PAGE_VALID;
275 }
276 
277 /*
278  * In v2:
279  * 31:12 - Page address bit 31:0
280  * 11: 8 - Page address bit 35:32
281  *  7: 4 - Page address bit 39:36
282  *     3 - Security
283  *     2 - Writable
284  *     1 - Readable
285  *     0 - 1 if Page @ Page address is valid
286  */
287 
rk_mk_pte_v2(phys_addr_t page,int prot)288 static u32 rk_mk_pte_v2(phys_addr_t page, int prot)
289 {
290 	u32 flags = 0;
291 
292 	flags |= (prot & IOMMU_READ) ? RK_PTE_PAGE_READABLE : 0;
293 	flags |= (prot & IOMMU_WRITE) ? RK_PTE_PAGE_WRITABLE : 0;
294 
295 	return rk_mk_dte_v2(page) | flags;
296 }
297 
rk_mk_pte_invalid(u32 pte)298 static u32 rk_mk_pte_invalid(u32 pte)
299 {
300 	return pte & ~RK_PTE_PAGE_VALID;
301 }
302 
303 /*
304  * rk3288 iova (IOMMU Virtual Address) format
305  *  31       22.21       12.11          0
306  * +-----------+-----------+-------------+
307  * | DTE index | PTE index | Page offset |
308  * +-----------+-----------+-------------+
309  *  31:22 - DTE index   - index of DTE in DT
310  *  21:12 - PTE index   - index of PTE in PT @ DTE.pt_address
311  *  11: 0 - Page offset - offset into page @ PTE.page_address
312  */
313 #define RK_IOVA_DTE_MASK    0xffc00000
314 #define RK_IOVA_DTE_SHIFT   22
315 #define RK_IOVA_PTE_MASK    0x003ff000
316 #define RK_IOVA_PTE_SHIFT   12
317 #define RK_IOVA_PAGE_MASK   0x00000fff
318 #define RK_IOVA_PAGE_SHIFT  0
319 
rk_iova_dte_index(dma_addr_t iova)320 static u32 rk_iova_dte_index(dma_addr_t iova)
321 {
322 	return (u32)(iova & RK_IOVA_DTE_MASK) >> RK_IOVA_DTE_SHIFT;
323 }
324 
rk_iova_pte_index(dma_addr_t iova)325 static u32 rk_iova_pte_index(dma_addr_t iova)
326 {
327 	return (u32)(iova & RK_IOVA_PTE_MASK) >> RK_IOVA_PTE_SHIFT;
328 }
329 
rk_iova_page_offset(dma_addr_t iova)330 static u32 rk_iova_page_offset(dma_addr_t iova)
331 {
332 	return (u32)(iova & RK_IOVA_PAGE_MASK) >> RK_IOVA_PAGE_SHIFT;
333 }
334 
rk_iommu_read(void __iomem * base,u32 offset)335 static u32 rk_iommu_read(void __iomem *base, u32 offset)
336 {
337 	return readl(base + offset);
338 }
339 
rk_iommu_write(void __iomem * base,u32 offset,u32 value)340 static void rk_iommu_write(void __iomem *base, u32 offset, u32 value)
341 {
342 	writel(value, base + offset);
343 }
344 
rk_iommu_command(struct rk_iommu * iommu,u32 command)345 static void rk_iommu_command(struct rk_iommu *iommu, u32 command)
346 {
347 	int i;
348 
349 	for (i = 0; i < iommu->num_mmu; i++)
350 		writel(command, iommu->bases[i] + RK_MMU_COMMAND);
351 }
352 
rk_iommu_base_command(void __iomem * base,u32 command)353 static void rk_iommu_base_command(void __iomem *base, u32 command)
354 {
355 	writel(command, base + RK_MMU_COMMAND);
356 }
rk_iommu_zap_lines(struct rk_iommu * iommu,dma_addr_t iova_start,size_t size)357 static void rk_iommu_zap_lines(struct rk_iommu *iommu, dma_addr_t iova_start,
358 			       size_t size)
359 {
360 	int i;
361 	dma_addr_t iova_end = iova_start + size;
362 	/*
363 	 * TODO(djkurtz): Figure out when it is more efficient to shootdown the
364 	 * entire iotlb rather than iterate over individual iovas.
365 	 */
366 	for (i = 0; i < iommu->num_mmu; i++) {
367 		dma_addr_t iova;
368 
369 		for (iova = iova_start; iova < iova_end; iova += SPAGE_SIZE)
370 			rk_iommu_write(iommu->bases[i], RK_MMU_ZAP_ONE_LINE, iova);
371 	}
372 }
373 
rk_iommu_is_stall_active(struct rk_iommu * iommu)374 static bool rk_iommu_is_stall_active(struct rk_iommu *iommu)
375 {
376 	bool active = true;
377 	int i;
378 
379 	for (i = 0; i < iommu->num_mmu; i++)
380 		active &= !!(rk_iommu_read(iommu->bases[i], RK_MMU_STATUS) &
381 					   RK_MMU_STATUS_STALL_ACTIVE);
382 
383 	return active;
384 }
385 
rk_iommu_is_paging_enabled(struct rk_iommu * iommu)386 static bool rk_iommu_is_paging_enabled(struct rk_iommu *iommu)
387 {
388 	bool enable = true;
389 	int i;
390 
391 	for (i = 0; i < iommu->num_mmu; i++)
392 		enable &= !!(rk_iommu_read(iommu->bases[i], RK_MMU_STATUS) &
393 					   RK_MMU_STATUS_PAGING_ENABLED);
394 
395 	return enable;
396 }
397 
rk_iommu_is_reset_done(struct rk_iommu * iommu)398 static bool rk_iommu_is_reset_done(struct rk_iommu *iommu)
399 {
400 	bool done = true;
401 	int i;
402 
403 	for (i = 0; i < iommu->num_mmu; i++)
404 		done &= rk_iommu_read(iommu->bases[i], RK_MMU_DTE_ADDR) == 0;
405 
406 	return done;
407 }
408 
rk_iommu_enable_stall(struct rk_iommu * iommu)409 static int rk_iommu_enable_stall(struct rk_iommu *iommu)
410 {
411 	int ret, i;
412 	bool val;
413 
414 	if (rk_iommu_is_stall_active(iommu))
415 		return 0;
416 
417 	/* Stall can only be enabled if paging is enabled */
418 	if (!rk_iommu_is_paging_enabled(iommu))
419 		return 0;
420 
421 	rk_iommu_command(iommu, RK_MMU_CMD_ENABLE_STALL);
422 
423 	ret = readx_poll_timeout(rk_iommu_is_stall_active, 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, "Enable stall request timed out, status: %#08x\n",
429 				rk_iommu_read(iommu->bases[i], RK_MMU_STATUS));
430 
431 	return ret;
432 }
433 
rk_iommu_disable_stall(struct rk_iommu * iommu)434 static int rk_iommu_disable_stall(struct rk_iommu *iommu)
435 {
436 	int ret, i;
437 	bool val;
438 
439 	if (!rk_iommu_is_stall_active(iommu))
440 		return 0;
441 
442 	rk_iommu_command(iommu, RK_MMU_CMD_DISABLE_STALL);
443 
444 	ret = readx_poll_timeout(rk_iommu_is_stall_active, iommu, val,
445 				 !val, RK_MMU_POLL_PERIOD_US,
446 				 RK_MMU_POLL_TIMEOUT_US);
447 	if (ret)
448 		for (i = 0; i < iommu->num_mmu; i++)
449 			dev_err(iommu->dev, "Disable stall request timed out, status: %#08x\n",
450 				rk_iommu_read(iommu->bases[i], RK_MMU_STATUS));
451 
452 	return ret;
453 }
454 
rk_iommu_enable_paging(struct rk_iommu * iommu)455 static int rk_iommu_enable_paging(struct rk_iommu *iommu)
456 {
457 	int ret, i;
458 	bool val;
459 
460 	if (rk_iommu_is_paging_enabled(iommu))
461 		return 0;
462 
463 	rk_iommu_command(iommu, RK_MMU_CMD_ENABLE_PAGING);
464 
465 	ret = readx_poll_timeout(rk_iommu_is_paging_enabled, iommu, val,
466 				 val, RK_MMU_POLL_PERIOD_US,
467 				 RK_MMU_POLL_TIMEOUT_US);
468 	if (ret)
469 		for (i = 0; i < iommu->num_mmu; i++)
470 			dev_err(iommu->dev, "Enable paging request timed out, status: %#08x\n",
471 				rk_iommu_read(iommu->bases[i], RK_MMU_STATUS));
472 
473 	return ret;
474 }
475 
rk_iommu_disable_paging(struct rk_iommu * iommu)476 static int rk_iommu_disable_paging(struct rk_iommu *iommu)
477 {
478 	int ret, i;
479 	bool val;
480 
481 	if (!rk_iommu_is_paging_enabled(iommu))
482 		return 0;
483 
484 	rk_iommu_command(iommu, RK_MMU_CMD_DISABLE_PAGING);
485 
486 	ret = readx_poll_timeout(rk_iommu_is_paging_enabled, iommu, val,
487 				 !val, RK_MMU_POLL_PERIOD_US,
488 				 RK_MMU_POLL_TIMEOUT_US);
489 	if (ret)
490 		for (i = 0; i < iommu->num_mmu; i++)
491 			dev_err(iommu->dev, "Disable paging request timed out, status: %#08x\n",
492 				rk_iommu_read(iommu->bases[i], RK_MMU_STATUS));
493 
494 	return ret;
495 }
496 
rk_iommu_force_reset(struct rk_iommu * iommu)497 static int rk_iommu_force_reset(struct rk_iommu *iommu)
498 {
499 	int ret, i;
500 	u32 dte_addr;
501 	bool val;
502 
503 	if (iommu->reset_disabled)
504 		return 0;
505 
506 	/*
507 	 * Check if register DTE_ADDR is working by writing DTE_ADDR_DUMMY
508 	 * and verifying that upper 5 (v1) or 7 (v2) nybbles are read back.
509 	 */
510 	for (i = 0; i < iommu->num_mmu; i++) {
511 		dte_addr = rk_ops->pt_address(DTE_ADDR_DUMMY);
512 		rk_iommu_write(iommu->bases[i], RK_MMU_DTE_ADDR, dte_addr);
513 
514 		if (dte_addr != rk_iommu_read(iommu->bases[i], RK_MMU_DTE_ADDR)) {
515 			dev_err(iommu->dev, "Error during raw reset. MMU_DTE_ADDR is not functioning\n");
516 			return -EFAULT;
517 		}
518 	}
519 
520 	rk_iommu_command(iommu, RK_MMU_CMD_FORCE_RESET);
521 
522 	ret = readx_poll_timeout(rk_iommu_is_reset_done, iommu, val,
523 				 val, RK_MMU_FORCE_RESET_TIMEOUT_US,
524 				 RK_MMU_POLL_TIMEOUT_US);
525 	if (ret) {
526 		dev_err(iommu->dev, "FORCE_RESET command timed out\n");
527 		return ret;
528 	}
529 
530 	return 0;
531 }
532 
log_iova(struct rk_iommu * iommu,int index,dma_addr_t iova)533 static void log_iova(struct rk_iommu *iommu, int index, dma_addr_t iova)
534 {
535 	void __iomem *base = iommu->bases[index];
536 	u32 dte_index, pte_index, page_offset;
537 	u32 mmu_dte_addr;
538 	phys_addr_t mmu_dte_addr_phys, dte_addr_phys;
539 	u32 *dte_addr;
540 	u32 dte;
541 	phys_addr_t pte_addr_phys = 0;
542 	u32 *pte_addr = NULL;
543 	u32 pte = 0;
544 	phys_addr_t page_addr_phys = 0;
545 	u32 page_flags = 0;
546 
547 	dte_index = rk_iova_dte_index(iova);
548 	pte_index = rk_iova_pte_index(iova);
549 	page_offset = rk_iova_page_offset(iova);
550 
551 	mmu_dte_addr = rk_iommu_read(base, RK_MMU_DTE_ADDR);
552 	mmu_dte_addr_phys = rk_ops->pt_address(mmu_dte_addr);
553 
554 	dte_addr_phys = mmu_dte_addr_phys + (4 * dte_index);
555 	dte_addr = phys_to_virt(dte_addr_phys);
556 	dte = *dte_addr;
557 
558 	if (!rk_dte_is_pt_valid(dte))
559 		goto print_it;
560 
561 	pte_addr_phys = rk_ops->pt_address(dte) + (pte_index * 4);
562 	pte_addr = phys_to_virt(pte_addr_phys);
563 	pte = *pte_addr;
564 
565 	if (!rk_pte_is_page_valid(pte))
566 		goto print_it;
567 
568 	page_addr_phys = rk_ops->pt_address(pte) + page_offset;
569 	page_flags = pte & RK_PTE_PAGE_FLAGS_MASK;
570 
571 print_it:
572 	dev_err(iommu->dev, "iova = %pad: dte_index: %#03x pte_index: %#03x page_offset: %#03x\n",
573 		&iova, dte_index, pte_index, page_offset);
574 	dev_err(iommu->dev, "mmu_dte_addr: %pa dte@%pa: %#08x valid: %u pte@%pa: %#08x valid: %u page@%pa flags: %#03x\n",
575 		&mmu_dte_addr_phys, &dte_addr_phys, dte,
576 		rk_dte_is_pt_valid(dte), &pte_addr_phys, pte,
577 		rk_pte_is_page_valid(pte), &page_addr_phys, page_flags);
578 }
579 
rk_iommu_irq(int irq,void * dev_id)580 static irqreturn_t rk_iommu_irq(int irq, void *dev_id)
581 {
582 	struct rk_iommu *iommu = dev_id;
583 	u32 status;
584 	u32 int_status;
585 	dma_addr_t iova;
586 	irqreturn_t ret = IRQ_NONE;
587 	int i, err;
588 
589 	err = pm_runtime_get_if_in_use(iommu->dev);
590 	if (!err || WARN_ON_ONCE(err < 0))
591 		return ret;
592 
593 	if (WARN_ON(clk_bulk_enable(iommu->num_clocks, iommu->clocks)))
594 		goto out;
595 
596 	for (i = 0; i < iommu->num_mmu; i++) {
597 		int_status = rk_iommu_read(iommu->bases[i], RK_MMU_INT_STATUS);
598 		if (int_status == 0)
599 			continue;
600 
601 		ret = IRQ_HANDLED;
602 		iova = rk_iommu_read(iommu->bases[i], RK_MMU_PAGE_FAULT_ADDR);
603 
604 		if (int_status & RK_MMU_IRQ_PAGE_FAULT) {
605 			int flags;
606 
607 			status = rk_iommu_read(iommu->bases[i], RK_MMU_STATUS);
608 			flags = (status & RK_MMU_STATUS_PAGE_FAULT_IS_WRITE) ?
609 					IOMMU_FAULT_WRITE : IOMMU_FAULT_READ;
610 
611 			dev_err(iommu->dev, "Page fault at %pad of type %s\n",
612 				&iova,
613 				(flags == IOMMU_FAULT_WRITE) ? "write" : "read");
614 
615 			log_iova(iommu, i, iova);
616 
617 			/*
618 			 * Report page fault to any installed handlers.
619 			 * Ignore the return code, though, since we always zap cache
620 			 * and clear the page fault anyway.
621 			 */
622 			if (iommu->domain != &rk_identity_domain)
623 				report_iommu_fault(iommu->domain, iommu->dev, iova,
624 						   flags);
625 			else
626 				dev_err(iommu->dev, "Page fault while iommu not attached to domain?\n");
627 
628 			rk_iommu_base_command(iommu->bases[i], RK_MMU_CMD_ZAP_CACHE);
629 			rk_iommu_base_command(iommu->bases[i], RK_MMU_CMD_PAGE_FAULT_DONE);
630 		}
631 
632 		if (int_status & RK_MMU_IRQ_BUS_ERROR)
633 			dev_err(iommu->dev, "BUS_ERROR occurred at %pad\n", &iova);
634 
635 		if (int_status & ~RK_MMU_IRQ_MASK)
636 			dev_err(iommu->dev, "unexpected int_status: %#08x\n",
637 				int_status);
638 
639 		rk_iommu_write(iommu->bases[i], RK_MMU_INT_CLEAR, int_status);
640 	}
641 
642 	clk_bulk_disable(iommu->num_clocks, iommu->clocks);
643 
644 out:
645 	pm_runtime_put(iommu->dev);
646 	return ret;
647 }
648 
rk_iommu_iova_to_phys(struct iommu_domain * domain,dma_addr_t iova)649 static phys_addr_t rk_iommu_iova_to_phys(struct iommu_domain *domain,
650 					 dma_addr_t iova)
651 {
652 	struct rk_iommu_domain *rk_domain = to_rk_domain(domain);
653 	unsigned long flags;
654 	phys_addr_t pt_phys, phys = 0;
655 	u32 dte, pte;
656 	u32 *page_table;
657 
658 	spin_lock_irqsave(&rk_domain->dt_lock, flags);
659 
660 	dte = rk_domain->dt[rk_iova_dte_index(iova)];
661 	if (!rk_dte_is_pt_valid(dte))
662 		goto out;
663 
664 	pt_phys = rk_ops->pt_address(dte);
665 	page_table = (u32 *)phys_to_virt(pt_phys);
666 	pte = page_table[rk_iova_pte_index(iova)];
667 	if (!rk_pte_is_page_valid(pte))
668 		goto out;
669 
670 	phys = rk_ops->pt_address(pte) + rk_iova_page_offset(iova);
671 out:
672 	spin_unlock_irqrestore(&rk_domain->dt_lock, flags);
673 
674 	return phys;
675 }
676 
rk_iommu_zap_iova(struct rk_iommu_domain * rk_domain,dma_addr_t iova,size_t size)677 static void rk_iommu_zap_iova(struct rk_iommu_domain *rk_domain,
678 			      dma_addr_t iova, size_t size)
679 {
680 	struct list_head *pos;
681 	unsigned long flags;
682 
683 	/* shootdown these iova from all iommus using this domain */
684 	spin_lock_irqsave(&rk_domain->iommus_lock, flags);
685 	list_for_each(pos, &rk_domain->iommus) {
686 		struct rk_iommu *iommu;
687 		int ret;
688 
689 		iommu = list_entry(pos, struct rk_iommu, node);
690 
691 		/* Only zap TLBs of IOMMUs that are powered on. */
692 		ret = pm_runtime_get_if_in_use(iommu->dev);
693 		if (WARN_ON_ONCE(ret < 0))
694 			continue;
695 		if (ret) {
696 			WARN_ON(clk_bulk_enable(iommu->num_clocks,
697 						iommu->clocks));
698 			rk_iommu_zap_lines(iommu, iova, size);
699 			clk_bulk_disable(iommu->num_clocks, iommu->clocks);
700 			pm_runtime_put(iommu->dev);
701 		}
702 	}
703 	spin_unlock_irqrestore(&rk_domain->iommus_lock, flags);
704 }
705 
rk_iommu_zap_iova_first_last(struct rk_iommu_domain * rk_domain,dma_addr_t iova,size_t size)706 static void rk_iommu_zap_iova_first_last(struct rk_iommu_domain *rk_domain,
707 					 dma_addr_t iova, size_t size)
708 {
709 	rk_iommu_zap_iova(rk_domain, iova, SPAGE_SIZE);
710 	if (size > SPAGE_SIZE)
711 		rk_iommu_zap_iova(rk_domain, iova + size - SPAGE_SIZE,
712 					SPAGE_SIZE);
713 }
714 
rk_dte_get_page_table(struct rk_iommu_domain * rk_domain,dma_addr_t iova)715 static u32 *rk_dte_get_page_table(struct rk_iommu_domain *rk_domain,
716 				  dma_addr_t iova)
717 {
718 	u32 *page_table, *dte_addr;
719 	u32 dte_index, dte;
720 	phys_addr_t pt_phys;
721 	dma_addr_t pt_dma;
722 
723 	assert_spin_locked(&rk_domain->dt_lock);
724 
725 	dte_index = rk_iova_dte_index(iova);
726 	dte_addr = &rk_domain->dt[dte_index];
727 	dte = *dte_addr;
728 	if (rk_dte_is_pt_valid(dte))
729 		goto done;
730 
731 	page_table = (u32 *)get_zeroed_page(GFP_ATOMIC | rk_ops->gfp_flags);
732 	if (!page_table)
733 		return ERR_PTR(-ENOMEM);
734 
735 	pt_dma = dma_map_single(dma_dev, page_table, SPAGE_SIZE, DMA_TO_DEVICE);
736 	if (dma_mapping_error(dma_dev, pt_dma)) {
737 		dev_err(dma_dev, "DMA mapping error while allocating page table\n");
738 		free_page((unsigned long)page_table);
739 		return ERR_PTR(-ENOMEM);
740 	}
741 
742 	dte = rk_ops->mk_dtentries(pt_dma);
743 	*dte_addr = dte;
744 
745 	rk_table_flush(rk_domain,
746 		       rk_domain->dt_dma + dte_index * sizeof(u32), 1);
747 done:
748 	pt_phys = rk_ops->pt_address(dte);
749 	return (u32 *)phys_to_virt(pt_phys);
750 }
751 
rk_iommu_unmap_iova(struct rk_iommu_domain * rk_domain,u32 * pte_addr,dma_addr_t pte_dma,size_t size)752 static size_t rk_iommu_unmap_iova(struct rk_iommu_domain *rk_domain,
753 				  u32 *pte_addr, dma_addr_t pte_dma,
754 				  size_t size)
755 {
756 	unsigned int pte_count;
757 	unsigned int pte_total = size / SPAGE_SIZE;
758 
759 	assert_spin_locked(&rk_domain->dt_lock);
760 
761 	for (pte_count = 0; pte_count < pte_total; pte_count++) {
762 		u32 pte = pte_addr[pte_count];
763 		if (!rk_pte_is_page_valid(pte))
764 			break;
765 
766 		pte_addr[pte_count] = rk_mk_pte_invalid(pte);
767 	}
768 
769 	rk_table_flush(rk_domain, pte_dma, pte_count);
770 
771 	return pte_count * SPAGE_SIZE;
772 }
773 
rk_iommu_map_iova(struct rk_iommu_domain * rk_domain,u32 * pte_addr,dma_addr_t pte_dma,dma_addr_t iova,phys_addr_t paddr,size_t size,int prot)774 static int rk_iommu_map_iova(struct rk_iommu_domain *rk_domain, u32 *pte_addr,
775 			     dma_addr_t pte_dma, dma_addr_t iova,
776 			     phys_addr_t paddr, size_t size, int prot)
777 {
778 	unsigned int pte_count;
779 	unsigned int pte_total = size / SPAGE_SIZE;
780 	phys_addr_t page_phys;
781 
782 	assert_spin_locked(&rk_domain->dt_lock);
783 
784 	for (pte_count = 0; pte_count < pte_total; pte_count++) {
785 		u32 pte = pte_addr[pte_count];
786 
787 		if (rk_pte_is_page_valid(pte))
788 			goto unwind;
789 
790 		pte_addr[pte_count] = rk_ops->mk_ptentries(paddr, prot);
791 
792 		paddr += SPAGE_SIZE;
793 	}
794 
795 	rk_table_flush(rk_domain, pte_dma, pte_total);
796 
797 	/*
798 	 * Zap the first and last iova to evict from iotlb any previously
799 	 * mapped cachelines holding stale values for its dte and pte.
800 	 * We only zap the first and last iova, since only they could have
801 	 * dte or pte shared with an existing mapping.
802 	 */
803 	rk_iommu_zap_iova_first_last(rk_domain, iova, size);
804 
805 	return 0;
806 unwind:
807 	/* Unmap the range of iovas that we just mapped */
808 	rk_iommu_unmap_iova(rk_domain, pte_addr, pte_dma,
809 			    pte_count * SPAGE_SIZE);
810 
811 	iova += pte_count * SPAGE_SIZE;
812 	page_phys = rk_ops->pt_address(pte_addr[pte_count]);
813 	pr_err("iova: %pad already mapped to %pa cannot remap to phys: %pa prot: %#x\n",
814 	       &iova, &page_phys, &paddr, prot);
815 
816 	return -EADDRINUSE;
817 }
818 
rk_iommu_map(struct iommu_domain * domain,unsigned long _iova,phys_addr_t paddr,size_t size,int prot,gfp_t gfp)819 static int rk_iommu_map(struct iommu_domain *domain, unsigned long _iova,
820 			phys_addr_t paddr, size_t size, int prot, gfp_t gfp)
821 {
822 	struct rk_iommu_domain *rk_domain = to_rk_domain(domain);
823 	unsigned long flags;
824 	dma_addr_t pte_dma, iova = (dma_addr_t)_iova;
825 	u32 *page_table, *pte_addr;
826 	u32 dte_index, pte_index;
827 	int ret;
828 
829 	spin_lock_irqsave(&rk_domain->dt_lock, flags);
830 
831 	/*
832 	 * pgsize_bitmap specifies iova sizes that fit in one page table
833 	 * (1024 4-KiB pages = 4 MiB).
834 	 * So, size will always be 4096 <= size <= 4194304.
835 	 * Since iommu_map() guarantees that both iova and size will be
836 	 * aligned, we will always only be mapping from a single dte here.
837 	 */
838 	page_table = rk_dte_get_page_table(rk_domain, iova);
839 	if (IS_ERR(page_table)) {
840 		spin_unlock_irqrestore(&rk_domain->dt_lock, flags);
841 		return PTR_ERR(page_table);
842 	}
843 
844 	dte_index = rk_domain->dt[rk_iova_dte_index(iova)];
845 	pte_index = rk_iova_pte_index(iova);
846 	pte_addr = &page_table[pte_index];
847 
848 	pte_dma = rk_ops->pt_address(dte_index) + pte_index * sizeof(u32);
849 	ret = rk_iommu_map_iova(rk_domain, pte_addr, pte_dma, iova,
850 				paddr, size, prot);
851 
852 	spin_unlock_irqrestore(&rk_domain->dt_lock, flags);
853 
854 	return ret;
855 }
856 
rk_iommu_unmap(struct iommu_domain * domain,unsigned long _iova,size_t size,struct iommu_iotlb_gather * gather)857 static size_t rk_iommu_unmap(struct iommu_domain *domain, unsigned long _iova,
858 			     size_t size, struct iommu_iotlb_gather *gather)
859 {
860 	struct rk_iommu_domain *rk_domain = to_rk_domain(domain);
861 	unsigned long flags;
862 	dma_addr_t pte_dma, iova = (dma_addr_t)_iova;
863 	phys_addr_t pt_phys;
864 	u32 dte;
865 	u32 *pte_addr;
866 	size_t unmap_size;
867 
868 	spin_lock_irqsave(&rk_domain->dt_lock, flags);
869 
870 	/*
871 	 * pgsize_bitmap specifies iova sizes that fit in one page table
872 	 * (1024 4-KiB pages = 4 MiB).
873 	 * So, size will always be 4096 <= size <= 4194304.
874 	 * Since iommu_unmap() guarantees that both iova and size will be
875 	 * aligned, we will always only be unmapping from a single dte here.
876 	 */
877 	dte = rk_domain->dt[rk_iova_dte_index(iova)];
878 	/* Just return 0 if iova is unmapped */
879 	if (!rk_dte_is_pt_valid(dte)) {
880 		spin_unlock_irqrestore(&rk_domain->dt_lock, flags);
881 		return 0;
882 	}
883 
884 	pt_phys = rk_ops->pt_address(dte);
885 	pte_addr = (u32 *)phys_to_virt(pt_phys) + rk_iova_pte_index(iova);
886 	pte_dma = pt_phys + rk_iova_pte_index(iova) * sizeof(u32);
887 	unmap_size = rk_iommu_unmap_iova(rk_domain, pte_addr, pte_dma, size);
888 
889 	spin_unlock_irqrestore(&rk_domain->dt_lock, flags);
890 
891 	/* Shootdown iotlb entries for iova range that was just unmapped */
892 	rk_iommu_zap_iova(rk_domain, iova, unmap_size);
893 
894 	return unmap_size;
895 }
896 
rk_iommu_from_dev(struct device * dev)897 static struct rk_iommu *rk_iommu_from_dev(struct device *dev)
898 {
899 	struct rk_iommudata *data = dev_iommu_priv_get(dev);
900 
901 	return data ? data->iommu : NULL;
902 }
903 
904 /* Must be called with iommu powered on and attached */
rk_iommu_disable(struct rk_iommu * iommu)905 static void rk_iommu_disable(struct rk_iommu *iommu)
906 {
907 	int i;
908 
909 	/* Ignore error while disabling, just keep going */
910 	WARN_ON(clk_bulk_enable(iommu->num_clocks, iommu->clocks));
911 	rk_iommu_enable_stall(iommu);
912 	rk_iommu_disable_paging(iommu);
913 	for (i = 0; i < iommu->num_mmu; i++) {
914 		rk_iommu_write(iommu->bases[i], RK_MMU_INT_MASK, 0);
915 		rk_iommu_write(iommu->bases[i], RK_MMU_DTE_ADDR, 0);
916 	}
917 	rk_iommu_disable_stall(iommu);
918 	clk_bulk_disable(iommu->num_clocks, iommu->clocks);
919 }
920 
921 /* Must be called with iommu powered on and attached */
rk_iommu_enable(struct rk_iommu * iommu)922 static int rk_iommu_enable(struct rk_iommu *iommu)
923 {
924 	struct iommu_domain *domain = iommu->domain;
925 	struct rk_iommu_domain *rk_domain = to_rk_domain(domain);
926 	int ret, i;
927 
928 	ret = clk_bulk_enable(iommu->num_clocks, iommu->clocks);
929 	if (ret)
930 		return ret;
931 
932 	ret = rk_iommu_enable_stall(iommu);
933 	if (ret)
934 		goto out_disable_clocks;
935 
936 	ret = rk_iommu_force_reset(iommu);
937 	if (ret)
938 		goto out_disable_stall;
939 
940 	for (i = 0; i < iommu->num_mmu; i++) {
941 		rk_iommu_write(iommu->bases[i], RK_MMU_DTE_ADDR,
942 			       rk_ops->mk_dtentries(rk_domain->dt_dma));
943 		rk_iommu_base_command(iommu->bases[i], RK_MMU_CMD_ZAP_CACHE);
944 		rk_iommu_write(iommu->bases[i], RK_MMU_INT_MASK, RK_MMU_IRQ_MASK);
945 	}
946 
947 	ret = rk_iommu_enable_paging(iommu);
948 
949 out_disable_stall:
950 	rk_iommu_disable_stall(iommu);
951 out_disable_clocks:
952 	clk_bulk_disable(iommu->num_clocks, iommu->clocks);
953 	return ret;
954 }
955 
rk_iommu_identity_attach(struct iommu_domain * identity_domain,struct device * dev)956 static int rk_iommu_identity_attach(struct iommu_domain *identity_domain,
957 				    struct device *dev)
958 {
959 	struct rk_iommu *iommu;
960 	struct rk_iommu_domain *rk_domain;
961 	unsigned long flags;
962 	int ret;
963 
964 	/* Allow 'virtual devices' (eg drm) to detach from domain */
965 	iommu = rk_iommu_from_dev(dev);
966 	if (!iommu)
967 		return -ENODEV;
968 
969 	rk_domain = to_rk_domain(iommu->domain);
970 
971 	dev_dbg(dev, "Detaching from iommu domain\n");
972 
973 	if (iommu->domain == identity_domain)
974 		return 0;
975 
976 	iommu->domain = identity_domain;
977 
978 	spin_lock_irqsave(&rk_domain->iommus_lock, flags);
979 	list_del_init(&iommu->node);
980 	spin_unlock_irqrestore(&rk_domain->iommus_lock, flags);
981 
982 	ret = pm_runtime_get_if_in_use(iommu->dev);
983 	WARN_ON_ONCE(ret < 0);
984 	if (ret > 0) {
985 		rk_iommu_disable(iommu);
986 		pm_runtime_put(iommu->dev);
987 	}
988 
989 	return 0;
990 }
991 
rk_iommu_identity_free(struct iommu_domain * domain)992 static void rk_iommu_identity_free(struct iommu_domain *domain)
993 {
994 }
995 
996 static struct iommu_domain_ops rk_identity_ops = {
997 	.attach_dev = rk_iommu_identity_attach,
998 	.free = rk_iommu_identity_free,
999 };
1000 
1001 static struct iommu_domain rk_identity_domain = {
1002 	.type = IOMMU_DOMAIN_IDENTITY,
1003 	.ops = &rk_identity_ops,
1004 };
1005 
1006 #ifdef CONFIG_ARM
rk_iommu_set_platform_dma(struct device * dev)1007 static void rk_iommu_set_platform_dma(struct device *dev)
1008 {
1009 	WARN_ON(rk_iommu_identity_attach(&rk_identity_domain, dev));
1010 }
1011 #endif
1012 
rk_iommu_attach_device(struct iommu_domain * domain,struct device * dev)1013 static int rk_iommu_attach_device(struct iommu_domain *domain,
1014 		struct device *dev)
1015 {
1016 	struct rk_iommu *iommu;
1017 	struct rk_iommu_domain *rk_domain = to_rk_domain(domain);
1018 	unsigned long flags;
1019 	int ret;
1020 
1021 	/*
1022 	 * Allow 'virtual devices' (e.g., drm) to attach to domain.
1023 	 * Such a device does not belong to an iommu group.
1024 	 */
1025 	iommu = rk_iommu_from_dev(dev);
1026 	if (!iommu)
1027 		return 0;
1028 
1029 	dev_dbg(dev, "Attaching to iommu domain\n");
1030 
1031 	/* iommu already attached */
1032 	if (iommu->domain == domain)
1033 		return 0;
1034 
1035 	ret = rk_iommu_identity_attach(&rk_identity_domain, dev);
1036 	if (ret)
1037 		return ret;
1038 
1039 	iommu->domain = domain;
1040 
1041 	spin_lock_irqsave(&rk_domain->iommus_lock, flags);
1042 	list_add_tail(&iommu->node, &rk_domain->iommus);
1043 	spin_unlock_irqrestore(&rk_domain->iommus_lock, flags);
1044 
1045 	ret = pm_runtime_get_if_in_use(iommu->dev);
1046 	if (!ret || WARN_ON_ONCE(ret < 0))
1047 		return 0;
1048 
1049 	ret = rk_iommu_enable(iommu);
1050 	if (ret)
1051 		WARN_ON(rk_iommu_identity_attach(&rk_identity_domain, dev));
1052 
1053 	pm_runtime_put(iommu->dev);
1054 
1055 	return ret;
1056 }
1057 
rk_iommu_domain_alloc(unsigned type)1058 static struct iommu_domain *rk_iommu_domain_alloc(unsigned type)
1059 {
1060 	struct rk_iommu_domain *rk_domain;
1061 
1062 	if (type == IOMMU_DOMAIN_IDENTITY)
1063 		return &rk_identity_domain;
1064 
1065 	if (type != IOMMU_DOMAIN_UNMANAGED && type != IOMMU_DOMAIN_DMA)
1066 		return NULL;
1067 
1068 	if (!dma_dev)
1069 		return NULL;
1070 
1071 	rk_domain = kzalloc(sizeof(*rk_domain), GFP_KERNEL);
1072 	if (!rk_domain)
1073 		return NULL;
1074 
1075 	/*
1076 	 * rk32xx iommus use a 2 level pagetable.
1077 	 * Each level1 (dt) and level2 (pt) table has 1024 4-byte entries.
1078 	 * Allocate one 4 KiB page for each table.
1079 	 */
1080 	rk_domain->dt = (u32 *)get_zeroed_page(GFP_KERNEL | rk_ops->gfp_flags);
1081 	if (!rk_domain->dt)
1082 		goto err_free_domain;
1083 
1084 	rk_domain->dt_dma = dma_map_single(dma_dev, rk_domain->dt,
1085 					   SPAGE_SIZE, DMA_TO_DEVICE);
1086 	if (dma_mapping_error(dma_dev, rk_domain->dt_dma)) {
1087 		dev_err(dma_dev, "DMA map error for DT\n");
1088 		goto err_free_dt;
1089 	}
1090 
1091 	spin_lock_init(&rk_domain->iommus_lock);
1092 	spin_lock_init(&rk_domain->dt_lock);
1093 	INIT_LIST_HEAD(&rk_domain->iommus);
1094 
1095 	rk_domain->domain.geometry.aperture_start = 0;
1096 	rk_domain->domain.geometry.aperture_end   = DMA_BIT_MASK(32);
1097 	rk_domain->domain.geometry.force_aperture = true;
1098 
1099 	return &rk_domain->domain;
1100 
1101 err_free_dt:
1102 	free_page((unsigned long)rk_domain->dt);
1103 err_free_domain:
1104 	kfree(rk_domain);
1105 
1106 	return NULL;
1107 }
1108 
rk_iommu_domain_free(struct iommu_domain * domain)1109 static void rk_iommu_domain_free(struct iommu_domain *domain)
1110 {
1111 	struct rk_iommu_domain *rk_domain = to_rk_domain(domain);
1112 	int i;
1113 
1114 	WARN_ON(!list_empty(&rk_domain->iommus));
1115 
1116 	for (i = 0; i < NUM_DT_ENTRIES; i++) {
1117 		u32 dte = rk_domain->dt[i];
1118 		if (rk_dte_is_pt_valid(dte)) {
1119 			phys_addr_t pt_phys = rk_ops->pt_address(dte);
1120 			u32 *page_table = phys_to_virt(pt_phys);
1121 			dma_unmap_single(dma_dev, pt_phys,
1122 					 SPAGE_SIZE, DMA_TO_DEVICE);
1123 			free_page((unsigned long)page_table);
1124 		}
1125 	}
1126 
1127 	dma_unmap_single(dma_dev, rk_domain->dt_dma,
1128 			 SPAGE_SIZE, DMA_TO_DEVICE);
1129 	free_page((unsigned long)rk_domain->dt);
1130 
1131 	kfree(rk_domain);
1132 }
1133 
rk_iommu_probe_device(struct device * dev)1134 static struct iommu_device *rk_iommu_probe_device(struct device *dev)
1135 {
1136 	struct rk_iommudata *data;
1137 	struct rk_iommu *iommu;
1138 
1139 	data = dev_iommu_priv_get(dev);
1140 	if (!data)
1141 		return ERR_PTR(-ENODEV);
1142 
1143 	iommu = rk_iommu_from_dev(dev);
1144 
1145 	data->link = device_link_add(dev, iommu->dev,
1146 				     DL_FLAG_STATELESS | DL_FLAG_PM_RUNTIME);
1147 
1148 	return &iommu->iommu;
1149 }
1150 
rk_iommu_release_device(struct device * dev)1151 static void rk_iommu_release_device(struct device *dev)
1152 {
1153 	struct rk_iommudata *data = dev_iommu_priv_get(dev);
1154 
1155 	device_link_del(data->link);
1156 }
1157 
rk_iommu_device_group(struct device * dev)1158 static struct iommu_group *rk_iommu_device_group(struct device *dev)
1159 {
1160 	struct rk_iommu *iommu;
1161 
1162 	iommu = rk_iommu_from_dev(dev);
1163 
1164 	return iommu_group_ref_get(iommu->group);
1165 }
1166 
rk_iommu_of_xlate(struct device * dev,struct of_phandle_args * args)1167 static int rk_iommu_of_xlate(struct device *dev,
1168 			     struct of_phandle_args *args)
1169 {
1170 	struct platform_device *iommu_dev;
1171 	struct rk_iommudata *data;
1172 
1173 	data = devm_kzalloc(dma_dev, sizeof(*data), GFP_KERNEL);
1174 	if (!data)
1175 		return -ENOMEM;
1176 
1177 	iommu_dev = of_find_device_by_node(args->np);
1178 
1179 	data->iommu = platform_get_drvdata(iommu_dev);
1180 	data->iommu->domain = &rk_identity_domain;
1181 	dev_iommu_priv_set(dev, data);
1182 
1183 	platform_device_put(iommu_dev);
1184 
1185 	return 0;
1186 }
1187 
1188 static const struct iommu_ops rk_iommu_ops = {
1189 	.domain_alloc = rk_iommu_domain_alloc,
1190 	.probe_device = rk_iommu_probe_device,
1191 	.release_device = rk_iommu_release_device,
1192 	.device_group = rk_iommu_device_group,
1193 #ifdef CONFIG_ARM
1194 	.set_platform_dma_ops = rk_iommu_set_platform_dma,
1195 #endif
1196 	.pgsize_bitmap = RK_IOMMU_PGSIZE_BITMAP,
1197 	.of_xlate = rk_iommu_of_xlate,
1198 	.default_domain_ops = &(const struct iommu_domain_ops) {
1199 		.attach_dev	= rk_iommu_attach_device,
1200 		.map		= rk_iommu_map,
1201 		.unmap		= rk_iommu_unmap,
1202 		.iova_to_phys	= rk_iommu_iova_to_phys,
1203 		.free		= rk_iommu_domain_free,
1204 	}
1205 };
1206 
rk_iommu_probe(struct platform_device * pdev)1207 static int rk_iommu_probe(struct platform_device *pdev)
1208 {
1209 	struct device *dev = &pdev->dev;
1210 	struct rk_iommu *iommu;
1211 	struct resource *res;
1212 	const struct rk_iommu_ops *ops;
1213 	int num_res = pdev->num_resources;
1214 	int err, i;
1215 
1216 	iommu = devm_kzalloc(dev, sizeof(*iommu), GFP_KERNEL);
1217 	if (!iommu)
1218 		return -ENOMEM;
1219 
1220 	platform_set_drvdata(pdev, iommu);
1221 	iommu->dev = dev;
1222 	iommu->num_mmu = 0;
1223 
1224 	ops = of_device_get_match_data(dev);
1225 	if (!rk_ops)
1226 		rk_ops = ops;
1227 
1228 	/*
1229 	 * That should not happen unless different versions of the
1230 	 * hardware block are embedded the same SoC
1231 	 */
1232 	if (WARN_ON(rk_ops != ops))
1233 		return -EINVAL;
1234 
1235 	iommu->bases = devm_kcalloc(dev, num_res, sizeof(*iommu->bases),
1236 				    GFP_KERNEL);
1237 	if (!iommu->bases)
1238 		return -ENOMEM;
1239 
1240 	for (i = 0; i < num_res; i++) {
1241 		res = platform_get_resource(pdev, IORESOURCE_MEM, i);
1242 		if (!res)
1243 			continue;
1244 		iommu->bases[i] = devm_ioremap_resource(&pdev->dev, res);
1245 		if (IS_ERR(iommu->bases[i]))
1246 			continue;
1247 		iommu->num_mmu++;
1248 	}
1249 	if (iommu->num_mmu == 0)
1250 		return PTR_ERR(iommu->bases[0]);
1251 
1252 	iommu->num_irq = platform_irq_count(pdev);
1253 	if (iommu->num_irq < 0)
1254 		return iommu->num_irq;
1255 
1256 	iommu->reset_disabled = device_property_read_bool(dev,
1257 					"rockchip,disable-mmu-reset");
1258 
1259 	iommu->num_clocks = ARRAY_SIZE(rk_iommu_clocks);
1260 	iommu->clocks = devm_kcalloc(iommu->dev, iommu->num_clocks,
1261 				     sizeof(*iommu->clocks), GFP_KERNEL);
1262 	if (!iommu->clocks)
1263 		return -ENOMEM;
1264 
1265 	for (i = 0; i < iommu->num_clocks; ++i)
1266 		iommu->clocks[i].id = rk_iommu_clocks[i];
1267 
1268 	/*
1269 	 * iommu clocks should be present for all new devices and devicetrees
1270 	 * but there are older devicetrees without clocks out in the wild.
1271 	 * So clocks as optional for the time being.
1272 	 */
1273 	err = devm_clk_bulk_get(iommu->dev, iommu->num_clocks, iommu->clocks);
1274 	if (err == -ENOENT)
1275 		iommu->num_clocks = 0;
1276 	else if (err)
1277 		return err;
1278 
1279 	err = clk_bulk_prepare(iommu->num_clocks, iommu->clocks);
1280 	if (err)
1281 		return err;
1282 
1283 	iommu->group = iommu_group_alloc();
1284 	if (IS_ERR(iommu->group)) {
1285 		err = PTR_ERR(iommu->group);
1286 		goto err_unprepare_clocks;
1287 	}
1288 
1289 	err = iommu_device_sysfs_add(&iommu->iommu, dev, NULL, dev_name(dev));
1290 	if (err)
1291 		goto err_put_group;
1292 
1293 	err = iommu_device_register(&iommu->iommu, &rk_iommu_ops, dev);
1294 	if (err)
1295 		goto err_remove_sysfs;
1296 
1297 	/*
1298 	 * Use the first registered IOMMU device for domain to use with DMA
1299 	 * API, since a domain might not physically correspond to a single
1300 	 * IOMMU device..
1301 	 */
1302 	if (!dma_dev)
1303 		dma_dev = &pdev->dev;
1304 
1305 	pm_runtime_enable(dev);
1306 
1307 	for (i = 0; i < iommu->num_irq; i++) {
1308 		int irq = platform_get_irq(pdev, i);
1309 
1310 		if (irq < 0) {
1311 			err = irq;
1312 			goto err_pm_disable;
1313 		}
1314 
1315 		err = devm_request_irq(iommu->dev, irq, rk_iommu_irq,
1316 				       IRQF_SHARED, dev_name(dev), iommu);
1317 		if (err)
1318 			goto err_pm_disable;
1319 	}
1320 
1321 	dma_set_mask_and_coherent(dev, rk_ops->dma_bit_mask);
1322 
1323 	return 0;
1324 err_pm_disable:
1325 	pm_runtime_disable(dev);
1326 err_remove_sysfs:
1327 	iommu_device_sysfs_remove(&iommu->iommu);
1328 err_put_group:
1329 	iommu_group_put(iommu->group);
1330 err_unprepare_clocks:
1331 	clk_bulk_unprepare(iommu->num_clocks, iommu->clocks);
1332 	return err;
1333 }
1334 
rk_iommu_shutdown(struct platform_device * pdev)1335 static void rk_iommu_shutdown(struct platform_device *pdev)
1336 {
1337 	struct rk_iommu *iommu = platform_get_drvdata(pdev);
1338 	int i;
1339 
1340 	for (i = 0; i < iommu->num_irq; i++) {
1341 		int irq = platform_get_irq(pdev, i);
1342 
1343 		devm_free_irq(iommu->dev, irq, iommu);
1344 	}
1345 
1346 	pm_runtime_force_suspend(&pdev->dev);
1347 }
1348 
rk_iommu_suspend(struct device * dev)1349 static int __maybe_unused rk_iommu_suspend(struct device *dev)
1350 {
1351 	struct rk_iommu *iommu = dev_get_drvdata(dev);
1352 
1353 	if (iommu->domain == &rk_identity_domain)
1354 		return 0;
1355 
1356 	rk_iommu_disable(iommu);
1357 	return 0;
1358 }
1359 
rk_iommu_resume(struct device * dev)1360 static int __maybe_unused rk_iommu_resume(struct device *dev)
1361 {
1362 	struct rk_iommu *iommu = dev_get_drvdata(dev);
1363 
1364 	if (iommu->domain == &rk_identity_domain)
1365 		return 0;
1366 
1367 	return rk_iommu_enable(iommu);
1368 }
1369 
1370 static const struct dev_pm_ops rk_iommu_pm_ops = {
1371 	SET_RUNTIME_PM_OPS(rk_iommu_suspend, rk_iommu_resume, NULL)
1372 	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
1373 				pm_runtime_force_resume)
1374 };
1375 
1376 static struct rk_iommu_ops iommu_data_ops_v1 = {
1377 	.pt_address = &rk_dte_pt_address,
1378 	.mk_dtentries = &rk_mk_dte,
1379 	.mk_ptentries = &rk_mk_pte,
1380 	.dma_bit_mask = DMA_BIT_MASK(32),
1381 	.gfp_flags = GFP_DMA32,
1382 };
1383 
1384 static struct rk_iommu_ops iommu_data_ops_v2 = {
1385 	.pt_address = &rk_dte_pt_address_v2,
1386 	.mk_dtentries = &rk_mk_dte_v2,
1387 	.mk_ptentries = &rk_mk_pte_v2,
1388 	.dma_bit_mask = DMA_BIT_MASK(40),
1389 	.gfp_flags = 0,
1390 };
1391 
1392 static const struct of_device_id rk_iommu_dt_ids[] = {
1393 	{	.compatible = "rockchip,iommu",
1394 		.data = &iommu_data_ops_v1,
1395 	},
1396 	{	.compatible = "rockchip,rk3568-iommu",
1397 		.data = &iommu_data_ops_v2,
1398 	},
1399 	{ /* sentinel */ }
1400 };
1401 
1402 static struct platform_driver rk_iommu_driver = {
1403 	.probe = rk_iommu_probe,
1404 	.shutdown = rk_iommu_shutdown,
1405 	.driver = {
1406 		   .name = "rk_iommu",
1407 		   .of_match_table = rk_iommu_dt_ids,
1408 		   .pm = &rk_iommu_pm_ops,
1409 		   .suppress_bind_attrs = true,
1410 	},
1411 };
1412 builtin_platform_driver(rk_iommu_driver);
1413