xref: /linux/drivers/iommu/exynos-iommu.c (revision e6a901a00822659181c93c86d8bbc2a17779fddc)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2011,2016 Samsung Electronics Co., Ltd.
4  *		http://www.samsung.com
5  */
6 
7 #ifdef CONFIG_EXYNOS_IOMMU_DEBUG
8 #define DEBUG
9 #endif
10 
11 #include <linux/clk.h>
12 #include <linux/dma-mapping.h>
13 #include <linux/err.h>
14 #include <linux/io.h>
15 #include <linux/iommu.h>
16 #include <linux/interrupt.h>
17 #include <linux/kmemleak.h>
18 #include <linux/list.h>
19 #include <linux/of.h>
20 #include <linux/of_platform.h>
21 #include <linux/platform_device.h>
22 #include <linux/pm_runtime.h>
23 #include <linux/slab.h>
24 
25 typedef u32 sysmmu_iova_t;
26 typedef u32 sysmmu_pte_t;
27 static struct iommu_domain exynos_identity_domain;
28 
29 /* We do not consider super section mapping (16MB) */
30 #define SECT_ORDER 20
31 #define LPAGE_ORDER 16
32 #define SPAGE_ORDER 12
33 
34 #define SECT_SIZE (1 << SECT_ORDER)
35 #define LPAGE_SIZE (1 << LPAGE_ORDER)
36 #define SPAGE_SIZE (1 << SPAGE_ORDER)
37 
38 #define SECT_MASK (~(SECT_SIZE - 1))
39 #define LPAGE_MASK (~(LPAGE_SIZE - 1))
40 #define SPAGE_MASK (~(SPAGE_SIZE - 1))
41 
42 #define lv1ent_fault(sent) ((*(sent) == ZERO_LV2LINK) || \
43 			   ((*(sent) & 3) == 0) || ((*(sent) & 3) == 3))
44 #define lv1ent_zero(sent) (*(sent) == ZERO_LV2LINK)
45 #define lv1ent_page_zero(sent) ((*(sent) & 3) == 1)
46 #define lv1ent_page(sent) ((*(sent) != ZERO_LV2LINK) && \
47 			  ((*(sent) & 3) == 1))
48 #define lv1ent_section(sent) ((*(sent) & 3) == 2)
49 
50 #define lv2ent_fault(pent) ((*(pent) & 3) == 0)
51 #define lv2ent_small(pent) ((*(pent) & 2) == 2)
52 #define lv2ent_large(pent) ((*(pent) & 3) == 1)
53 
54 /*
55  * v1.x - v3.x SYSMMU supports 32bit physical and 32bit virtual address spaces
56  * v5.0 introduced support for 36bit physical address space by shifting
57  * all page entry values by 4 bits.
58  * All SYSMMU controllers in the system support the address spaces of the same
59  * size, so PG_ENT_SHIFT can be initialized on first SYSMMU probe to proper
60  * value (0 or 4).
61  */
62 static short PG_ENT_SHIFT = -1;
63 #define SYSMMU_PG_ENT_SHIFT 0
64 #define SYSMMU_V5_PG_ENT_SHIFT 4
65 
66 static const sysmmu_pte_t *LV1_PROT;
67 static const sysmmu_pte_t SYSMMU_LV1_PROT[] = {
68 	((0 << 15) | (0 << 10)), /* no access */
69 	((1 << 15) | (1 << 10)), /* IOMMU_READ only */
70 	((0 << 15) | (1 << 10)), /* IOMMU_WRITE not supported, use read/write */
71 	((0 << 15) | (1 << 10)), /* IOMMU_READ | IOMMU_WRITE */
72 };
73 static const sysmmu_pte_t SYSMMU_V5_LV1_PROT[] = {
74 	(0 << 4), /* no access */
75 	(1 << 4), /* IOMMU_READ only */
76 	(2 << 4), /* IOMMU_WRITE only */
77 	(3 << 4), /* IOMMU_READ | IOMMU_WRITE */
78 };
79 
80 static const sysmmu_pte_t *LV2_PROT;
81 static const sysmmu_pte_t SYSMMU_LV2_PROT[] = {
82 	((0 << 9) | (0 << 4)), /* no access */
83 	((1 << 9) | (1 << 4)), /* IOMMU_READ only */
84 	((0 << 9) | (1 << 4)), /* IOMMU_WRITE not supported, use read/write */
85 	((0 << 9) | (1 << 4)), /* IOMMU_READ | IOMMU_WRITE */
86 };
87 static const sysmmu_pte_t SYSMMU_V5_LV2_PROT[] = {
88 	(0 << 2), /* no access */
89 	(1 << 2), /* IOMMU_READ only */
90 	(2 << 2), /* IOMMU_WRITE only */
91 	(3 << 2), /* IOMMU_READ | IOMMU_WRITE */
92 };
93 
94 #define SYSMMU_SUPPORTED_PROT_BITS (IOMMU_READ | IOMMU_WRITE)
95 
96 #define sect_to_phys(ent) (((phys_addr_t) ent) << PG_ENT_SHIFT)
97 #define section_phys(sent) (sect_to_phys(*(sent)) & SECT_MASK)
98 #define section_offs(iova) (iova & (SECT_SIZE - 1))
99 #define lpage_phys(pent) (sect_to_phys(*(pent)) & LPAGE_MASK)
100 #define lpage_offs(iova) (iova & (LPAGE_SIZE - 1))
101 #define spage_phys(pent) (sect_to_phys(*(pent)) & SPAGE_MASK)
102 #define spage_offs(iova) (iova & (SPAGE_SIZE - 1))
103 
104 #define NUM_LV1ENTRIES 4096
105 #define NUM_LV2ENTRIES (SECT_SIZE / SPAGE_SIZE)
106 
107 static u32 lv1ent_offset(sysmmu_iova_t iova)
108 {
109 	return iova >> SECT_ORDER;
110 }
111 
112 static u32 lv2ent_offset(sysmmu_iova_t iova)
113 {
114 	return (iova >> SPAGE_ORDER) & (NUM_LV2ENTRIES - 1);
115 }
116 
117 #define LV1TABLE_SIZE (NUM_LV1ENTRIES * sizeof(sysmmu_pte_t))
118 #define LV2TABLE_SIZE (NUM_LV2ENTRIES * sizeof(sysmmu_pte_t))
119 
120 #define SPAGES_PER_LPAGE (LPAGE_SIZE / SPAGE_SIZE)
121 #define lv2table_base(sent) (sect_to_phys(*(sent) & 0xFFFFFFC0))
122 
123 #define mk_lv1ent_sect(pa, prot) ((pa >> PG_ENT_SHIFT) | LV1_PROT[prot] | 2)
124 #define mk_lv1ent_page(pa) ((pa >> PG_ENT_SHIFT) | 1)
125 #define mk_lv2ent_lpage(pa, prot) ((pa >> PG_ENT_SHIFT) | LV2_PROT[prot] | 1)
126 #define mk_lv2ent_spage(pa, prot) ((pa >> PG_ENT_SHIFT) | LV2_PROT[prot] | 2)
127 
128 #define CTRL_ENABLE	0x5
129 #define CTRL_BLOCK	0x7
130 #define CTRL_DISABLE	0x0
131 
132 #define CFG_LRU		0x1
133 #define CFG_EAP		(1 << 2)
134 #define CFG_QOS(n)	((n & 0xF) << 7)
135 #define CFG_ACGEN	(1 << 24) /* System MMU 3.3 only */
136 #define CFG_SYSSEL	(1 << 22) /* System MMU 3.2 only */
137 #define CFG_FLPDCACHE	(1 << 20) /* System MMU 3.2+ only */
138 
139 #define CTRL_VM_ENABLE			BIT(0)
140 #define CTRL_VM_FAULT_MODE_STALL	BIT(3)
141 #define CAPA0_CAPA1_EXIST		BIT(11)
142 #define CAPA1_VCR_ENABLED		BIT(14)
143 
144 /* common registers */
145 #define REG_MMU_CTRL		0x000
146 #define REG_MMU_CFG		0x004
147 #define REG_MMU_STATUS		0x008
148 #define REG_MMU_VERSION		0x034
149 
150 #define MMU_MAJ_VER(val)	((val) >> 7)
151 #define MMU_MIN_VER(val)	((val) & 0x7F)
152 #define MMU_RAW_VER(reg)	(((reg) >> 21) & ((1 << 11) - 1)) /* 11 bits */
153 
154 #define MAKE_MMU_VER(maj, min)	((((maj) & 0xF) << 7) | ((min) & 0x7F))
155 
156 /* v1.x - v3.x registers */
157 #define REG_PAGE_FAULT_ADDR	0x024
158 #define REG_AW_FAULT_ADDR	0x028
159 #define REG_AR_FAULT_ADDR	0x02C
160 #define REG_DEFAULT_SLAVE_ADDR	0x030
161 
162 /* v5.x registers */
163 #define REG_V5_FAULT_AR_VA	0x070
164 #define REG_V5_FAULT_AW_VA	0x080
165 
166 /* v7.x registers */
167 #define REG_V7_CAPA0		0x870
168 #define REG_V7_CAPA1		0x874
169 #define REG_V7_CTRL_VM		0x8000
170 
171 #define has_sysmmu(dev)		(dev_iommu_priv_get(dev) != NULL)
172 
173 static struct device *dma_dev;
174 static struct kmem_cache *lv2table_kmem_cache;
175 static sysmmu_pte_t *zero_lv2_table;
176 #define ZERO_LV2LINK mk_lv1ent_page(virt_to_phys(zero_lv2_table))
177 
178 static sysmmu_pte_t *section_entry(sysmmu_pte_t *pgtable, sysmmu_iova_t iova)
179 {
180 	return pgtable + lv1ent_offset(iova);
181 }
182 
183 static sysmmu_pte_t *page_entry(sysmmu_pte_t *sent, sysmmu_iova_t iova)
184 {
185 	return (sysmmu_pte_t *)phys_to_virt(
186 				lv2table_base(sent)) + lv2ent_offset(iova);
187 }
188 
189 struct sysmmu_fault {
190 	sysmmu_iova_t addr;	/* IOVA address that caused fault */
191 	const char *name;	/* human readable fault name */
192 	unsigned int type;	/* fault type for report_iommu_fault() */
193 };
194 
195 struct sysmmu_v1_fault_info {
196 	unsigned short addr_reg; /* register to read IOVA fault address */
197 	const char *name;	/* human readable fault name */
198 	unsigned int type;	/* fault type for report_iommu_fault */
199 };
200 
201 static const struct sysmmu_v1_fault_info sysmmu_v1_faults[] = {
202 	{ REG_PAGE_FAULT_ADDR, "PAGE", IOMMU_FAULT_READ },
203 	{ REG_AR_FAULT_ADDR, "MULTI-HIT", IOMMU_FAULT_READ },
204 	{ REG_AW_FAULT_ADDR, "MULTI-HIT", IOMMU_FAULT_WRITE },
205 	{ REG_DEFAULT_SLAVE_ADDR, "BUS ERROR", IOMMU_FAULT_READ },
206 	{ REG_AR_FAULT_ADDR, "SECURITY PROTECTION", IOMMU_FAULT_READ },
207 	{ REG_AR_FAULT_ADDR, "ACCESS PROTECTION", IOMMU_FAULT_READ },
208 	{ REG_AW_FAULT_ADDR, "SECURITY PROTECTION", IOMMU_FAULT_WRITE },
209 	{ REG_AW_FAULT_ADDR, "ACCESS PROTECTION", IOMMU_FAULT_WRITE },
210 };
211 
212 /* SysMMU v5 has the same faults for AR (0..4 bits) and AW (16..20 bits) */
213 static const char * const sysmmu_v5_fault_names[] = {
214 	"PTW",
215 	"PAGE",
216 	"MULTI-HIT",
217 	"ACCESS PROTECTION",
218 	"SECURITY PROTECTION"
219 };
220 
221 static const char * const sysmmu_v7_fault_names[] = {
222 	"PTW",
223 	"PAGE",
224 	"ACCESS PROTECTION",
225 	"RESERVED"
226 };
227 
228 /*
229  * This structure is attached to dev->iommu->priv of the master device
230  * on device add, contains a list of SYSMMU controllers defined by device tree,
231  * which are bound to given master device. It is usually referenced by 'owner'
232  * pointer.
233 */
234 struct exynos_iommu_owner {
235 	struct list_head controllers;	/* list of sysmmu_drvdata.owner_node */
236 	struct iommu_domain *domain;	/* domain this device is attached */
237 	struct mutex rpm_lock;		/* for runtime pm of all sysmmus */
238 };
239 
240 /*
241  * This structure exynos specific generalization of struct iommu_domain.
242  * It contains list of SYSMMU controllers from all master devices, which has
243  * been attached to this domain and page tables of IO address space defined by
244  * it. It is usually referenced by 'domain' pointer.
245  */
246 struct exynos_iommu_domain {
247 	struct list_head clients; /* list of sysmmu_drvdata.domain_node */
248 	sysmmu_pte_t *pgtable;	/* lv1 page table, 16KB */
249 	short *lv2entcnt;	/* free lv2 entry counter for each section */
250 	spinlock_t lock;	/* lock for modyfying list of clients */
251 	spinlock_t pgtablelock;	/* lock for modifying page table @ pgtable */
252 	struct iommu_domain domain; /* generic domain data structure */
253 };
254 
255 struct sysmmu_drvdata;
256 
257 /*
258  * SysMMU version specific data. Contains offsets for the registers which can
259  * be found in different SysMMU variants, but have different offset values.
260  * Also contains version specific callbacks to abstract the hardware.
261  */
262 struct sysmmu_variant {
263 	u32 pt_base;		/* page table base address (physical) */
264 	u32 flush_all;		/* invalidate all TLB entries */
265 	u32 flush_entry;	/* invalidate specific TLB entry */
266 	u32 flush_range;	/* invalidate TLB entries in specified range */
267 	u32 flush_start;	/* start address of range invalidation */
268 	u32 flush_end;		/* end address of range invalidation */
269 	u32 int_status;		/* interrupt status information */
270 	u32 int_clear;		/* clear the interrupt */
271 	u32 fault_va;		/* IOVA address that caused fault */
272 	u32 fault_info;		/* fault transaction info */
273 
274 	int (*get_fault_info)(struct sysmmu_drvdata *data, unsigned int itype,
275 			      struct sysmmu_fault *fault);
276 };
277 
278 /*
279  * This structure hold all data of a single SYSMMU controller, this includes
280  * hw resources like registers and clocks, pointers and list nodes to connect
281  * it to all other structures, internal state and parameters read from device
282  * tree. It is usually referenced by 'data' pointer.
283  */
284 struct sysmmu_drvdata {
285 	struct device *sysmmu;		/* SYSMMU controller device */
286 	struct device *master;		/* master device (owner) */
287 	struct device_link *link;	/* runtime PM link to master */
288 	void __iomem *sfrbase;		/* our registers */
289 	struct clk *clk;		/* SYSMMU's clock */
290 	struct clk *aclk;		/* SYSMMU's aclk clock */
291 	struct clk *pclk;		/* SYSMMU's pclk clock */
292 	struct clk *clk_master;		/* master's device clock */
293 	spinlock_t lock;		/* lock for modyfying state */
294 	bool active;			/* current status */
295 	struct exynos_iommu_domain *domain; /* domain we belong to */
296 	struct list_head domain_node;	/* node for domain clients list */
297 	struct list_head owner_node;	/* node for owner controllers list */
298 	phys_addr_t pgtable;		/* assigned page table structure */
299 	unsigned int version;		/* our version */
300 
301 	struct iommu_device iommu;	/* IOMMU core handle */
302 	const struct sysmmu_variant *variant; /* version specific data */
303 
304 	/* v7 fields */
305 	bool has_vcr;			/* virtual machine control register */
306 };
307 
308 #define SYSMMU_REG(data, reg) ((data)->sfrbase + (data)->variant->reg)
309 
310 static int exynos_sysmmu_v1_get_fault_info(struct sysmmu_drvdata *data,
311 					   unsigned int itype,
312 					   struct sysmmu_fault *fault)
313 {
314 	const struct sysmmu_v1_fault_info *finfo;
315 
316 	if (itype >= ARRAY_SIZE(sysmmu_v1_faults))
317 		return -ENXIO;
318 
319 	finfo = &sysmmu_v1_faults[itype];
320 	fault->addr = readl(data->sfrbase + finfo->addr_reg);
321 	fault->name = finfo->name;
322 	fault->type = finfo->type;
323 
324 	return 0;
325 }
326 
327 static int exynos_sysmmu_v5_get_fault_info(struct sysmmu_drvdata *data,
328 					   unsigned int itype,
329 					   struct sysmmu_fault *fault)
330 {
331 	unsigned int addr_reg;
332 
333 	if (itype < ARRAY_SIZE(sysmmu_v5_fault_names)) {
334 		fault->type = IOMMU_FAULT_READ;
335 		addr_reg = REG_V5_FAULT_AR_VA;
336 	} else if (itype >= 16 && itype <= 20) {
337 		fault->type = IOMMU_FAULT_WRITE;
338 		addr_reg = REG_V5_FAULT_AW_VA;
339 		itype -= 16;
340 	} else {
341 		return -ENXIO;
342 	}
343 
344 	fault->name = sysmmu_v5_fault_names[itype];
345 	fault->addr = readl(data->sfrbase + addr_reg);
346 
347 	return 0;
348 }
349 
350 static int exynos_sysmmu_v7_get_fault_info(struct sysmmu_drvdata *data,
351 					   unsigned int itype,
352 					   struct sysmmu_fault *fault)
353 {
354 	u32 info = readl(SYSMMU_REG(data, fault_info));
355 
356 	fault->addr = readl(SYSMMU_REG(data, fault_va));
357 	fault->name = sysmmu_v7_fault_names[itype % 4];
358 	fault->type = (info & BIT(20)) ? IOMMU_FAULT_WRITE : IOMMU_FAULT_READ;
359 
360 	return 0;
361 }
362 
363 /* SysMMU v1..v3 */
364 static const struct sysmmu_variant sysmmu_v1_variant = {
365 	.flush_all	= 0x0c,
366 	.flush_entry	= 0x10,
367 	.pt_base	= 0x14,
368 	.int_status	= 0x18,
369 	.int_clear	= 0x1c,
370 
371 	.get_fault_info	= exynos_sysmmu_v1_get_fault_info,
372 };
373 
374 /* SysMMU v5 */
375 static const struct sysmmu_variant sysmmu_v5_variant = {
376 	.pt_base	= 0x0c,
377 	.flush_all	= 0x10,
378 	.flush_entry	= 0x14,
379 	.flush_range	= 0x18,
380 	.flush_start	= 0x20,
381 	.flush_end	= 0x24,
382 	.int_status	= 0x60,
383 	.int_clear	= 0x64,
384 
385 	.get_fault_info	= exynos_sysmmu_v5_get_fault_info,
386 };
387 
388 /* SysMMU v7: non-VM capable register layout */
389 static const struct sysmmu_variant sysmmu_v7_variant = {
390 	.pt_base	= 0x0c,
391 	.flush_all	= 0x10,
392 	.flush_entry	= 0x14,
393 	.flush_range	= 0x18,
394 	.flush_start	= 0x20,
395 	.flush_end	= 0x24,
396 	.int_status	= 0x60,
397 	.int_clear	= 0x64,
398 	.fault_va	= 0x70,
399 	.fault_info	= 0x78,
400 
401 	.get_fault_info	= exynos_sysmmu_v7_get_fault_info,
402 };
403 
404 /* SysMMU v7: VM capable register layout */
405 static const struct sysmmu_variant sysmmu_v7_vm_variant = {
406 	.pt_base	= 0x800c,
407 	.flush_all	= 0x8010,
408 	.flush_entry	= 0x8014,
409 	.flush_range	= 0x8018,
410 	.flush_start	= 0x8020,
411 	.flush_end	= 0x8024,
412 	.int_status	= 0x60,
413 	.int_clear	= 0x64,
414 	.fault_va	= 0x1000,
415 	.fault_info	= 0x1004,
416 
417 	.get_fault_info	= exynos_sysmmu_v7_get_fault_info,
418 };
419 
420 static struct exynos_iommu_domain *to_exynos_domain(struct iommu_domain *dom)
421 {
422 	return container_of(dom, struct exynos_iommu_domain, domain);
423 }
424 
425 static void sysmmu_unblock(struct sysmmu_drvdata *data)
426 {
427 	writel(CTRL_ENABLE, data->sfrbase + REG_MMU_CTRL);
428 }
429 
430 static bool sysmmu_block(struct sysmmu_drvdata *data)
431 {
432 	int i = 120;
433 
434 	writel(CTRL_BLOCK, data->sfrbase + REG_MMU_CTRL);
435 	while ((i > 0) && !(readl(data->sfrbase + REG_MMU_STATUS) & 1))
436 		--i;
437 
438 	if (!(readl(data->sfrbase + REG_MMU_STATUS) & 1)) {
439 		sysmmu_unblock(data);
440 		return false;
441 	}
442 
443 	return true;
444 }
445 
446 static void __sysmmu_tlb_invalidate(struct sysmmu_drvdata *data)
447 {
448 	writel(0x1, SYSMMU_REG(data, flush_all));
449 }
450 
451 static void __sysmmu_tlb_invalidate_entry(struct sysmmu_drvdata *data,
452 				sysmmu_iova_t iova, unsigned int num_inv)
453 {
454 	unsigned int i;
455 
456 	if (MMU_MAJ_VER(data->version) < 5 || num_inv == 1) {
457 		for (i = 0; i < num_inv; i++) {
458 			writel((iova & SPAGE_MASK) | 1,
459 			       SYSMMU_REG(data, flush_entry));
460 			iova += SPAGE_SIZE;
461 		}
462 	} else {
463 		writel(iova & SPAGE_MASK, SYSMMU_REG(data, flush_start));
464 		writel((iova & SPAGE_MASK) + (num_inv - 1) * SPAGE_SIZE,
465 		       SYSMMU_REG(data, flush_end));
466 		writel(0x1, SYSMMU_REG(data, flush_range));
467 	}
468 }
469 
470 static void __sysmmu_set_ptbase(struct sysmmu_drvdata *data, phys_addr_t pgd)
471 {
472 	u32 pt_base;
473 
474 	if (MMU_MAJ_VER(data->version) < 5)
475 		pt_base = pgd;
476 	else
477 		pt_base = pgd >> SPAGE_ORDER;
478 
479 	writel(pt_base, SYSMMU_REG(data, pt_base));
480 	__sysmmu_tlb_invalidate(data);
481 }
482 
483 static void __sysmmu_enable_clocks(struct sysmmu_drvdata *data)
484 {
485 	BUG_ON(clk_prepare_enable(data->clk_master));
486 	BUG_ON(clk_prepare_enable(data->clk));
487 	BUG_ON(clk_prepare_enable(data->pclk));
488 	BUG_ON(clk_prepare_enable(data->aclk));
489 }
490 
491 static void __sysmmu_disable_clocks(struct sysmmu_drvdata *data)
492 {
493 	clk_disable_unprepare(data->aclk);
494 	clk_disable_unprepare(data->pclk);
495 	clk_disable_unprepare(data->clk);
496 	clk_disable_unprepare(data->clk_master);
497 }
498 
499 static bool __sysmmu_has_capa1(struct sysmmu_drvdata *data)
500 {
501 	u32 capa0 = readl(data->sfrbase + REG_V7_CAPA0);
502 
503 	return capa0 & CAPA0_CAPA1_EXIST;
504 }
505 
506 static void __sysmmu_get_vcr(struct sysmmu_drvdata *data)
507 {
508 	u32 capa1 = readl(data->sfrbase + REG_V7_CAPA1);
509 
510 	data->has_vcr = capa1 & CAPA1_VCR_ENABLED;
511 }
512 
513 static void __sysmmu_get_version(struct sysmmu_drvdata *data)
514 {
515 	u32 ver;
516 
517 	__sysmmu_enable_clocks(data);
518 
519 	ver = readl(data->sfrbase + REG_MMU_VERSION);
520 
521 	/* controllers on some SoCs don't report proper version */
522 	if (ver == 0x80000001u)
523 		data->version = MAKE_MMU_VER(1, 0);
524 	else
525 		data->version = MMU_RAW_VER(ver);
526 
527 	dev_dbg(data->sysmmu, "hardware version: %d.%d\n",
528 		MMU_MAJ_VER(data->version), MMU_MIN_VER(data->version));
529 
530 	if (MMU_MAJ_VER(data->version) < 5) {
531 		data->variant = &sysmmu_v1_variant;
532 	} else if (MMU_MAJ_VER(data->version) < 7) {
533 		data->variant = &sysmmu_v5_variant;
534 	} else {
535 		if (__sysmmu_has_capa1(data))
536 			__sysmmu_get_vcr(data);
537 		if (data->has_vcr)
538 			data->variant = &sysmmu_v7_vm_variant;
539 		else
540 			data->variant = &sysmmu_v7_variant;
541 	}
542 
543 	__sysmmu_disable_clocks(data);
544 }
545 
546 static void show_fault_information(struct sysmmu_drvdata *data,
547 				   const struct sysmmu_fault *fault)
548 {
549 	sysmmu_pte_t *ent;
550 
551 	dev_err(data->sysmmu, "%s: [%s] %s FAULT occurred at %#x\n",
552 		dev_name(data->master),
553 		fault->type == IOMMU_FAULT_READ ? "READ" : "WRITE",
554 		fault->name, fault->addr);
555 	dev_dbg(data->sysmmu, "Page table base: %pa\n", &data->pgtable);
556 	ent = section_entry(phys_to_virt(data->pgtable), fault->addr);
557 	dev_dbg(data->sysmmu, "\tLv1 entry: %#x\n", *ent);
558 	if (lv1ent_page(ent)) {
559 		ent = page_entry(ent, fault->addr);
560 		dev_dbg(data->sysmmu, "\t Lv2 entry: %#x\n", *ent);
561 	}
562 }
563 
564 static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
565 {
566 	struct sysmmu_drvdata *data = dev_id;
567 	unsigned int itype;
568 	struct sysmmu_fault fault;
569 	int ret = -ENOSYS;
570 
571 	WARN_ON(!data->active);
572 
573 	spin_lock(&data->lock);
574 	clk_enable(data->clk_master);
575 
576 	itype = __ffs(readl(SYSMMU_REG(data, int_status)));
577 	ret = data->variant->get_fault_info(data, itype, &fault);
578 	if (ret) {
579 		dev_err(data->sysmmu, "Unhandled interrupt bit %u\n", itype);
580 		goto out;
581 	}
582 	show_fault_information(data, &fault);
583 
584 	if (data->domain) {
585 		ret = report_iommu_fault(&data->domain->domain, data->master,
586 					 fault.addr, fault.type);
587 	}
588 	if (ret)
589 		panic("Unrecoverable System MMU Fault!");
590 
591 out:
592 	writel(1 << itype, SYSMMU_REG(data, int_clear));
593 
594 	/* SysMMU is in blocked state when interrupt occurred */
595 	sysmmu_unblock(data);
596 	clk_disable(data->clk_master);
597 	spin_unlock(&data->lock);
598 
599 	return IRQ_HANDLED;
600 }
601 
602 static void __sysmmu_disable(struct sysmmu_drvdata *data)
603 {
604 	unsigned long flags;
605 
606 	clk_enable(data->clk_master);
607 
608 	spin_lock_irqsave(&data->lock, flags);
609 	writel(CTRL_DISABLE, data->sfrbase + REG_MMU_CTRL);
610 	writel(0, data->sfrbase + REG_MMU_CFG);
611 	data->active = false;
612 	spin_unlock_irqrestore(&data->lock, flags);
613 
614 	__sysmmu_disable_clocks(data);
615 }
616 
617 static void __sysmmu_init_config(struct sysmmu_drvdata *data)
618 {
619 	unsigned int cfg;
620 
621 	if (data->version <= MAKE_MMU_VER(3, 1))
622 		cfg = CFG_LRU | CFG_QOS(15);
623 	else if (data->version <= MAKE_MMU_VER(3, 2))
624 		cfg = CFG_LRU | CFG_QOS(15) | CFG_FLPDCACHE | CFG_SYSSEL;
625 	else
626 		cfg = CFG_QOS(15) | CFG_FLPDCACHE | CFG_ACGEN;
627 
628 	cfg |= CFG_EAP; /* enable access protection bits check */
629 
630 	writel(cfg, data->sfrbase + REG_MMU_CFG);
631 }
632 
633 static void __sysmmu_enable_vid(struct sysmmu_drvdata *data)
634 {
635 	u32 ctrl;
636 
637 	if (MMU_MAJ_VER(data->version) < 7 || !data->has_vcr)
638 		return;
639 
640 	ctrl = readl(data->sfrbase + REG_V7_CTRL_VM);
641 	ctrl |= CTRL_VM_ENABLE | CTRL_VM_FAULT_MODE_STALL;
642 	writel(ctrl, data->sfrbase + REG_V7_CTRL_VM);
643 }
644 
645 static void __sysmmu_enable(struct sysmmu_drvdata *data)
646 {
647 	unsigned long flags;
648 
649 	__sysmmu_enable_clocks(data);
650 
651 	spin_lock_irqsave(&data->lock, flags);
652 	writel(CTRL_BLOCK, data->sfrbase + REG_MMU_CTRL);
653 	__sysmmu_init_config(data);
654 	__sysmmu_set_ptbase(data, data->pgtable);
655 	__sysmmu_enable_vid(data);
656 	writel(CTRL_ENABLE, data->sfrbase + REG_MMU_CTRL);
657 	data->active = true;
658 	spin_unlock_irqrestore(&data->lock, flags);
659 
660 	/*
661 	 * SYSMMU driver keeps master's clock enabled only for the short
662 	 * time, while accessing the registers. For performing address
663 	 * translation during DMA transaction it relies on the client
664 	 * driver to enable it.
665 	 */
666 	clk_disable(data->clk_master);
667 }
668 
669 static void sysmmu_tlb_invalidate_flpdcache(struct sysmmu_drvdata *data,
670 					    sysmmu_iova_t iova)
671 {
672 	unsigned long flags;
673 
674 	spin_lock_irqsave(&data->lock, flags);
675 	if (data->active && data->version >= MAKE_MMU_VER(3, 3)) {
676 		clk_enable(data->clk_master);
677 		if (sysmmu_block(data)) {
678 			if (data->version >= MAKE_MMU_VER(5, 0))
679 				__sysmmu_tlb_invalidate(data);
680 			else
681 				__sysmmu_tlb_invalidate_entry(data, iova, 1);
682 			sysmmu_unblock(data);
683 		}
684 		clk_disable(data->clk_master);
685 	}
686 	spin_unlock_irqrestore(&data->lock, flags);
687 }
688 
689 static void sysmmu_tlb_invalidate_entry(struct sysmmu_drvdata *data,
690 					sysmmu_iova_t iova, size_t size)
691 {
692 	unsigned long flags;
693 
694 	spin_lock_irqsave(&data->lock, flags);
695 	if (data->active) {
696 		unsigned int num_inv = 1;
697 
698 		clk_enable(data->clk_master);
699 
700 		/*
701 		 * L2TLB invalidation required
702 		 * 4KB page: 1 invalidation
703 		 * 64KB page: 16 invalidations
704 		 * 1MB page: 64 invalidations
705 		 * because it is set-associative TLB
706 		 * with 8-way and 64 sets.
707 		 * 1MB page can be cached in one of all sets.
708 		 * 64KB page can be one of 16 consecutive sets.
709 		 */
710 		if (MMU_MAJ_VER(data->version) == 2)
711 			num_inv = min_t(unsigned int, size / SPAGE_SIZE, 64);
712 
713 		if (sysmmu_block(data)) {
714 			__sysmmu_tlb_invalidate_entry(data, iova, num_inv);
715 			sysmmu_unblock(data);
716 		}
717 		clk_disable(data->clk_master);
718 	}
719 	spin_unlock_irqrestore(&data->lock, flags);
720 }
721 
722 static const struct iommu_ops exynos_iommu_ops;
723 
724 static int exynos_sysmmu_probe(struct platform_device *pdev)
725 {
726 	int irq, ret;
727 	struct device *dev = &pdev->dev;
728 	struct sysmmu_drvdata *data;
729 	struct resource *res;
730 
731 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
732 	if (!data)
733 		return -ENOMEM;
734 
735 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
736 	data->sfrbase = devm_ioremap_resource(dev, res);
737 	if (IS_ERR(data->sfrbase))
738 		return PTR_ERR(data->sfrbase);
739 
740 	irq = platform_get_irq(pdev, 0);
741 	if (irq <= 0)
742 		return irq;
743 
744 	ret = devm_request_irq(dev, irq, exynos_sysmmu_irq, 0,
745 				dev_name(dev), data);
746 	if (ret) {
747 		dev_err(dev, "Unabled to register handler of irq %d\n", irq);
748 		return ret;
749 	}
750 
751 	data->clk = devm_clk_get_optional(dev, "sysmmu");
752 	if (IS_ERR(data->clk))
753 		return PTR_ERR(data->clk);
754 
755 	data->aclk = devm_clk_get_optional(dev, "aclk");
756 	if (IS_ERR(data->aclk))
757 		return PTR_ERR(data->aclk);
758 
759 	data->pclk = devm_clk_get_optional(dev, "pclk");
760 	if (IS_ERR(data->pclk))
761 		return PTR_ERR(data->pclk);
762 
763 	if (!data->clk && (!data->aclk || !data->pclk)) {
764 		dev_err(dev, "Failed to get device clock(s)!\n");
765 		return -ENOSYS;
766 	}
767 
768 	data->clk_master = devm_clk_get_optional(dev, "master");
769 	if (IS_ERR(data->clk_master))
770 		return PTR_ERR(data->clk_master);
771 
772 	data->sysmmu = dev;
773 	spin_lock_init(&data->lock);
774 
775 	__sysmmu_get_version(data);
776 
777 	ret = iommu_device_sysfs_add(&data->iommu, &pdev->dev, NULL,
778 				     dev_name(data->sysmmu));
779 	if (ret)
780 		return ret;
781 
782 	platform_set_drvdata(pdev, data);
783 
784 	if (PG_ENT_SHIFT < 0) {
785 		if (MMU_MAJ_VER(data->version) < 5) {
786 			PG_ENT_SHIFT = SYSMMU_PG_ENT_SHIFT;
787 			LV1_PROT = SYSMMU_LV1_PROT;
788 			LV2_PROT = SYSMMU_LV2_PROT;
789 		} else {
790 			PG_ENT_SHIFT = SYSMMU_V5_PG_ENT_SHIFT;
791 			LV1_PROT = SYSMMU_V5_LV1_PROT;
792 			LV2_PROT = SYSMMU_V5_LV2_PROT;
793 		}
794 	}
795 
796 	if (MMU_MAJ_VER(data->version) >= 5) {
797 		ret = dma_set_mask(dev, DMA_BIT_MASK(36));
798 		if (ret) {
799 			dev_err(dev, "Unable to set DMA mask: %d\n", ret);
800 			goto err_dma_set_mask;
801 		}
802 	}
803 
804 	/*
805 	 * use the first registered sysmmu device for performing
806 	 * dma mapping operations on iommu page tables (cpu cache flush)
807 	 */
808 	if (!dma_dev)
809 		dma_dev = &pdev->dev;
810 
811 	pm_runtime_enable(dev);
812 
813 	ret = iommu_device_register(&data->iommu, &exynos_iommu_ops, dev);
814 	if (ret)
815 		goto err_dma_set_mask;
816 
817 	return 0;
818 
819 err_dma_set_mask:
820 	iommu_device_sysfs_remove(&data->iommu);
821 	return ret;
822 }
823 
824 static int __maybe_unused exynos_sysmmu_suspend(struct device *dev)
825 {
826 	struct sysmmu_drvdata *data = dev_get_drvdata(dev);
827 	struct device *master = data->master;
828 
829 	if (master) {
830 		struct exynos_iommu_owner *owner = dev_iommu_priv_get(master);
831 
832 		mutex_lock(&owner->rpm_lock);
833 		if (&data->domain->domain != &exynos_identity_domain) {
834 			dev_dbg(data->sysmmu, "saving state\n");
835 			__sysmmu_disable(data);
836 		}
837 		mutex_unlock(&owner->rpm_lock);
838 	}
839 	return 0;
840 }
841 
842 static int __maybe_unused exynos_sysmmu_resume(struct device *dev)
843 {
844 	struct sysmmu_drvdata *data = dev_get_drvdata(dev);
845 	struct device *master = data->master;
846 
847 	if (master) {
848 		struct exynos_iommu_owner *owner = dev_iommu_priv_get(master);
849 
850 		mutex_lock(&owner->rpm_lock);
851 		if (&data->domain->domain != &exynos_identity_domain) {
852 			dev_dbg(data->sysmmu, "restoring state\n");
853 			__sysmmu_enable(data);
854 		}
855 		mutex_unlock(&owner->rpm_lock);
856 	}
857 	return 0;
858 }
859 
860 static const struct dev_pm_ops sysmmu_pm_ops = {
861 	SET_RUNTIME_PM_OPS(exynos_sysmmu_suspend, exynos_sysmmu_resume, NULL)
862 	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
863 				pm_runtime_force_resume)
864 };
865 
866 static const struct of_device_id sysmmu_of_match[] = {
867 	{ .compatible	= "samsung,exynos-sysmmu", },
868 	{ },
869 };
870 
871 static struct platform_driver exynos_sysmmu_driver __refdata = {
872 	.probe	= exynos_sysmmu_probe,
873 	.driver	= {
874 		.name		= "exynos-sysmmu",
875 		.of_match_table	= sysmmu_of_match,
876 		.pm		= &sysmmu_pm_ops,
877 		.suppress_bind_attrs = true,
878 	}
879 };
880 
881 static inline void exynos_iommu_set_pte(sysmmu_pte_t *ent, sysmmu_pte_t val)
882 {
883 	dma_sync_single_for_cpu(dma_dev, virt_to_phys(ent), sizeof(*ent),
884 				DMA_TO_DEVICE);
885 	*ent = cpu_to_le32(val);
886 	dma_sync_single_for_device(dma_dev, virt_to_phys(ent), sizeof(*ent),
887 				   DMA_TO_DEVICE);
888 }
889 
890 static struct iommu_domain *exynos_iommu_domain_alloc_paging(struct device *dev)
891 {
892 	struct exynos_iommu_domain *domain;
893 	dma_addr_t handle;
894 	int i;
895 
896 	/* Check if correct PTE offsets are initialized */
897 	BUG_ON(PG_ENT_SHIFT < 0 || !dma_dev);
898 
899 	domain = kzalloc(sizeof(*domain), GFP_KERNEL);
900 	if (!domain)
901 		return NULL;
902 
903 	domain->pgtable = (sysmmu_pte_t *)__get_free_pages(GFP_KERNEL, 2);
904 	if (!domain->pgtable)
905 		goto err_pgtable;
906 
907 	domain->lv2entcnt = (short *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, 1);
908 	if (!domain->lv2entcnt)
909 		goto err_counter;
910 
911 	/* Workaround for System MMU v3.3 to prevent caching 1MiB mapping */
912 	for (i = 0; i < NUM_LV1ENTRIES; i++)
913 		domain->pgtable[i] = ZERO_LV2LINK;
914 
915 	handle = dma_map_single(dma_dev, domain->pgtable, LV1TABLE_SIZE,
916 				DMA_TO_DEVICE);
917 	/* For mapping page table entries we rely on dma == phys */
918 	BUG_ON(handle != virt_to_phys(domain->pgtable));
919 	if (dma_mapping_error(dma_dev, handle))
920 		goto err_lv2ent;
921 
922 	spin_lock_init(&domain->lock);
923 	spin_lock_init(&domain->pgtablelock);
924 	INIT_LIST_HEAD(&domain->clients);
925 
926 	domain->domain.geometry.aperture_start = 0;
927 	domain->domain.geometry.aperture_end   = ~0UL;
928 	domain->domain.geometry.force_aperture = true;
929 
930 	return &domain->domain;
931 
932 err_lv2ent:
933 	free_pages((unsigned long)domain->lv2entcnt, 1);
934 err_counter:
935 	free_pages((unsigned long)domain->pgtable, 2);
936 err_pgtable:
937 	kfree(domain);
938 	return NULL;
939 }
940 
941 static void exynos_iommu_domain_free(struct iommu_domain *iommu_domain)
942 {
943 	struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
944 	struct sysmmu_drvdata *data, *next;
945 	unsigned long flags;
946 	int i;
947 
948 	WARN_ON(!list_empty(&domain->clients));
949 
950 	spin_lock_irqsave(&domain->lock, flags);
951 
952 	list_for_each_entry_safe(data, next, &domain->clients, domain_node) {
953 		spin_lock(&data->lock);
954 		__sysmmu_disable(data);
955 		data->pgtable = 0;
956 		data->domain = NULL;
957 		list_del_init(&data->domain_node);
958 		spin_unlock(&data->lock);
959 	}
960 
961 	spin_unlock_irqrestore(&domain->lock, flags);
962 
963 	dma_unmap_single(dma_dev, virt_to_phys(domain->pgtable), LV1TABLE_SIZE,
964 			 DMA_TO_DEVICE);
965 
966 	for (i = 0; i < NUM_LV1ENTRIES; i++)
967 		if (lv1ent_page(domain->pgtable + i)) {
968 			phys_addr_t base = lv2table_base(domain->pgtable + i);
969 
970 			dma_unmap_single(dma_dev, base, LV2TABLE_SIZE,
971 					 DMA_TO_DEVICE);
972 			kmem_cache_free(lv2table_kmem_cache,
973 					phys_to_virt(base));
974 		}
975 
976 	free_pages((unsigned long)domain->pgtable, 2);
977 	free_pages((unsigned long)domain->lv2entcnt, 1);
978 	kfree(domain);
979 }
980 
981 static int exynos_iommu_identity_attach(struct iommu_domain *identity_domain,
982 					struct device *dev)
983 {
984 	struct exynos_iommu_owner *owner = dev_iommu_priv_get(dev);
985 	struct exynos_iommu_domain *domain;
986 	phys_addr_t pagetable;
987 	struct sysmmu_drvdata *data, *next;
988 	unsigned long flags;
989 
990 	if (owner->domain == identity_domain)
991 		return 0;
992 
993 	domain = to_exynos_domain(owner->domain);
994 	pagetable = virt_to_phys(domain->pgtable);
995 
996 	mutex_lock(&owner->rpm_lock);
997 
998 	list_for_each_entry(data, &owner->controllers, owner_node) {
999 		pm_runtime_get_noresume(data->sysmmu);
1000 		if (pm_runtime_active(data->sysmmu))
1001 			__sysmmu_disable(data);
1002 		pm_runtime_put(data->sysmmu);
1003 	}
1004 
1005 	spin_lock_irqsave(&domain->lock, flags);
1006 	list_for_each_entry_safe(data, next, &domain->clients, domain_node) {
1007 		spin_lock(&data->lock);
1008 		data->pgtable = 0;
1009 		data->domain = NULL;
1010 		list_del_init(&data->domain_node);
1011 		spin_unlock(&data->lock);
1012 	}
1013 	owner->domain = identity_domain;
1014 	spin_unlock_irqrestore(&domain->lock, flags);
1015 
1016 	mutex_unlock(&owner->rpm_lock);
1017 
1018 	dev_dbg(dev, "%s: Restored IOMMU to IDENTITY from pgtable %pa\n",
1019 		__func__, &pagetable);
1020 	return 0;
1021 }
1022 
1023 static struct iommu_domain_ops exynos_identity_ops = {
1024 	.attach_dev = exynos_iommu_identity_attach,
1025 };
1026 
1027 static struct iommu_domain exynos_identity_domain = {
1028 	.type = IOMMU_DOMAIN_IDENTITY,
1029 	.ops = &exynos_identity_ops,
1030 };
1031 
1032 static int exynos_iommu_attach_device(struct iommu_domain *iommu_domain,
1033 				   struct device *dev)
1034 {
1035 	struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
1036 	struct exynos_iommu_owner *owner = dev_iommu_priv_get(dev);
1037 	struct sysmmu_drvdata *data;
1038 	phys_addr_t pagetable = virt_to_phys(domain->pgtable);
1039 	unsigned long flags;
1040 	int err;
1041 
1042 	err = exynos_iommu_identity_attach(&exynos_identity_domain, dev);
1043 	if (err)
1044 		return err;
1045 
1046 	mutex_lock(&owner->rpm_lock);
1047 
1048 	spin_lock_irqsave(&domain->lock, flags);
1049 	list_for_each_entry(data, &owner->controllers, owner_node) {
1050 		spin_lock(&data->lock);
1051 		data->pgtable = pagetable;
1052 		data->domain = domain;
1053 		list_add_tail(&data->domain_node, &domain->clients);
1054 		spin_unlock(&data->lock);
1055 	}
1056 	owner->domain = iommu_domain;
1057 	spin_unlock_irqrestore(&domain->lock, flags);
1058 
1059 	list_for_each_entry(data, &owner->controllers, owner_node) {
1060 		pm_runtime_get_noresume(data->sysmmu);
1061 		if (pm_runtime_active(data->sysmmu))
1062 			__sysmmu_enable(data);
1063 		pm_runtime_put(data->sysmmu);
1064 	}
1065 
1066 	mutex_unlock(&owner->rpm_lock);
1067 
1068 	dev_dbg(dev, "%s: Attached IOMMU with pgtable %pa\n", __func__,
1069 		&pagetable);
1070 
1071 	return 0;
1072 }
1073 
1074 static sysmmu_pte_t *alloc_lv2entry(struct exynos_iommu_domain *domain,
1075 		sysmmu_pte_t *sent, sysmmu_iova_t iova, short *pgcounter)
1076 {
1077 	if (lv1ent_section(sent)) {
1078 		WARN(1, "Trying mapping on %#08x mapped with 1MiB page", iova);
1079 		return ERR_PTR(-EADDRINUSE);
1080 	}
1081 
1082 	if (lv1ent_fault(sent)) {
1083 		dma_addr_t handle;
1084 		sysmmu_pte_t *pent;
1085 		bool need_flush_flpd_cache = lv1ent_zero(sent);
1086 
1087 		pent = kmem_cache_zalloc(lv2table_kmem_cache, GFP_ATOMIC);
1088 		BUG_ON((uintptr_t)pent & (LV2TABLE_SIZE - 1));
1089 		if (!pent)
1090 			return ERR_PTR(-ENOMEM);
1091 
1092 		exynos_iommu_set_pte(sent, mk_lv1ent_page(virt_to_phys(pent)));
1093 		kmemleak_ignore(pent);
1094 		*pgcounter = NUM_LV2ENTRIES;
1095 		handle = dma_map_single(dma_dev, pent, LV2TABLE_SIZE,
1096 					DMA_TO_DEVICE);
1097 		if (dma_mapping_error(dma_dev, handle)) {
1098 			kmem_cache_free(lv2table_kmem_cache, pent);
1099 			return ERR_PTR(-EADDRINUSE);
1100 		}
1101 
1102 		/*
1103 		 * If pre-fetched SLPD is a faulty SLPD in zero_l2_table,
1104 		 * FLPD cache may cache the address of zero_l2_table. This
1105 		 * function replaces the zero_l2_table with new L2 page table
1106 		 * to write valid mappings.
1107 		 * Accessing the valid area may cause page fault since FLPD
1108 		 * cache may still cache zero_l2_table for the valid area
1109 		 * instead of new L2 page table that has the mapping
1110 		 * information of the valid area.
1111 		 * Thus any replacement of zero_l2_table with other valid L2
1112 		 * page table must involve FLPD cache invalidation for System
1113 		 * MMU v3.3.
1114 		 * FLPD cache invalidation is performed with TLB invalidation
1115 		 * by VPN without blocking. It is safe to invalidate TLB without
1116 		 * blocking because the target address of TLB invalidation is
1117 		 * not currently mapped.
1118 		 */
1119 		if (need_flush_flpd_cache) {
1120 			struct sysmmu_drvdata *data;
1121 
1122 			spin_lock(&domain->lock);
1123 			list_for_each_entry(data, &domain->clients, domain_node)
1124 				sysmmu_tlb_invalidate_flpdcache(data, iova);
1125 			spin_unlock(&domain->lock);
1126 		}
1127 	}
1128 
1129 	return page_entry(sent, iova);
1130 }
1131 
1132 static int lv1set_section(struct exynos_iommu_domain *domain,
1133 			  sysmmu_pte_t *sent, sysmmu_iova_t iova,
1134 			  phys_addr_t paddr, int prot, short *pgcnt)
1135 {
1136 	if (lv1ent_section(sent)) {
1137 		WARN(1, "Trying mapping on 1MiB@%#08x that is mapped",
1138 			iova);
1139 		return -EADDRINUSE;
1140 	}
1141 
1142 	if (lv1ent_page(sent)) {
1143 		if (*pgcnt != NUM_LV2ENTRIES) {
1144 			WARN(1, "Trying mapping on 1MiB@%#08x that is mapped",
1145 				iova);
1146 			return -EADDRINUSE;
1147 		}
1148 
1149 		kmem_cache_free(lv2table_kmem_cache, page_entry(sent, 0));
1150 		*pgcnt = 0;
1151 	}
1152 
1153 	exynos_iommu_set_pte(sent, mk_lv1ent_sect(paddr, prot));
1154 
1155 	spin_lock(&domain->lock);
1156 	if (lv1ent_page_zero(sent)) {
1157 		struct sysmmu_drvdata *data;
1158 		/*
1159 		 * Flushing FLPD cache in System MMU v3.3 that may cache a FLPD
1160 		 * entry by speculative prefetch of SLPD which has no mapping.
1161 		 */
1162 		list_for_each_entry(data, &domain->clients, domain_node)
1163 			sysmmu_tlb_invalidate_flpdcache(data, iova);
1164 	}
1165 	spin_unlock(&domain->lock);
1166 
1167 	return 0;
1168 }
1169 
1170 static int lv2set_page(sysmmu_pte_t *pent, phys_addr_t paddr, size_t size,
1171 		       int prot, short *pgcnt)
1172 {
1173 	if (size == SPAGE_SIZE) {
1174 		if (WARN_ON(!lv2ent_fault(pent)))
1175 			return -EADDRINUSE;
1176 
1177 		exynos_iommu_set_pte(pent, mk_lv2ent_spage(paddr, prot));
1178 		*pgcnt -= 1;
1179 	} else { /* size == LPAGE_SIZE */
1180 		int i;
1181 		dma_addr_t pent_base = virt_to_phys(pent);
1182 
1183 		dma_sync_single_for_cpu(dma_dev, pent_base,
1184 					sizeof(*pent) * SPAGES_PER_LPAGE,
1185 					DMA_TO_DEVICE);
1186 		for (i = 0; i < SPAGES_PER_LPAGE; i++, pent++) {
1187 			if (WARN_ON(!lv2ent_fault(pent))) {
1188 				if (i > 0)
1189 					memset(pent - i, 0, sizeof(*pent) * i);
1190 				return -EADDRINUSE;
1191 			}
1192 
1193 			*pent = mk_lv2ent_lpage(paddr, prot);
1194 		}
1195 		dma_sync_single_for_device(dma_dev, pent_base,
1196 					   sizeof(*pent) * SPAGES_PER_LPAGE,
1197 					   DMA_TO_DEVICE);
1198 		*pgcnt -= SPAGES_PER_LPAGE;
1199 	}
1200 
1201 	return 0;
1202 }
1203 
1204 /*
1205  * *CAUTION* to the I/O virtual memory managers that support exynos-iommu:
1206  *
1207  * System MMU v3.x has advanced logic to improve address translation
1208  * performance with caching more page table entries by a page table walk.
1209  * However, the logic has a bug that while caching faulty page table entries,
1210  * System MMU reports page fault if the cached fault entry is hit even though
1211  * the fault entry is updated to a valid entry after the entry is cached.
1212  * To prevent caching faulty page table entries which may be updated to valid
1213  * entries later, the virtual memory manager should care about the workaround
1214  * for the problem. The following describes the workaround.
1215  *
1216  * Any two consecutive I/O virtual address regions must have a hole of 128KiB
1217  * at maximum to prevent misbehavior of System MMU 3.x (workaround for h/w bug).
1218  *
1219  * Precisely, any start address of I/O virtual region must be aligned with
1220  * the following sizes for System MMU v3.1 and v3.2.
1221  * System MMU v3.1: 128KiB
1222  * System MMU v3.2: 256KiB
1223  *
1224  * Because System MMU v3.3 caches page table entries more aggressively, it needs
1225  * more workarounds.
1226  * - Any two consecutive I/O virtual regions must have a hole of size larger
1227  *   than or equal to 128KiB.
1228  * - Start address of an I/O virtual region must be aligned by 128KiB.
1229  */
1230 static int exynos_iommu_map(struct iommu_domain *iommu_domain,
1231 			    unsigned long l_iova, phys_addr_t paddr, size_t size,
1232 			    size_t count, int prot, gfp_t gfp, size_t *mapped)
1233 {
1234 	struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
1235 	sysmmu_pte_t *entry;
1236 	sysmmu_iova_t iova = (sysmmu_iova_t)l_iova;
1237 	unsigned long flags;
1238 	int ret = -ENOMEM;
1239 
1240 	BUG_ON(domain->pgtable == NULL);
1241 	prot &= SYSMMU_SUPPORTED_PROT_BITS;
1242 
1243 	spin_lock_irqsave(&domain->pgtablelock, flags);
1244 
1245 	entry = section_entry(domain->pgtable, iova);
1246 
1247 	if (size == SECT_SIZE) {
1248 		ret = lv1set_section(domain, entry, iova, paddr, prot,
1249 				     &domain->lv2entcnt[lv1ent_offset(iova)]);
1250 	} else {
1251 		sysmmu_pte_t *pent;
1252 
1253 		pent = alloc_lv2entry(domain, entry, iova,
1254 				      &domain->lv2entcnt[lv1ent_offset(iova)]);
1255 
1256 		if (IS_ERR(pent))
1257 			ret = PTR_ERR(pent);
1258 		else
1259 			ret = lv2set_page(pent, paddr, size, prot,
1260 				       &domain->lv2entcnt[lv1ent_offset(iova)]);
1261 	}
1262 
1263 	if (ret)
1264 		pr_err("%s: Failed(%d) to map %#zx bytes @ %#x\n",
1265 			__func__, ret, size, iova);
1266 	else
1267 		*mapped = size;
1268 
1269 	spin_unlock_irqrestore(&domain->pgtablelock, flags);
1270 
1271 	return ret;
1272 }
1273 
1274 static void exynos_iommu_tlb_invalidate_entry(struct exynos_iommu_domain *domain,
1275 					      sysmmu_iova_t iova, size_t size)
1276 {
1277 	struct sysmmu_drvdata *data;
1278 	unsigned long flags;
1279 
1280 	spin_lock_irqsave(&domain->lock, flags);
1281 
1282 	list_for_each_entry(data, &domain->clients, domain_node)
1283 		sysmmu_tlb_invalidate_entry(data, iova, size);
1284 
1285 	spin_unlock_irqrestore(&domain->lock, flags);
1286 }
1287 
1288 static size_t exynos_iommu_unmap(struct iommu_domain *iommu_domain,
1289 				 unsigned long l_iova, size_t size, size_t count,
1290 				 struct iommu_iotlb_gather *gather)
1291 {
1292 	struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
1293 	sysmmu_iova_t iova = (sysmmu_iova_t)l_iova;
1294 	sysmmu_pte_t *ent;
1295 	size_t err_pgsize;
1296 	unsigned long flags;
1297 
1298 	BUG_ON(domain->pgtable == NULL);
1299 
1300 	spin_lock_irqsave(&domain->pgtablelock, flags);
1301 
1302 	ent = section_entry(domain->pgtable, iova);
1303 
1304 	if (lv1ent_section(ent)) {
1305 		if (WARN_ON(size < SECT_SIZE)) {
1306 			err_pgsize = SECT_SIZE;
1307 			goto err;
1308 		}
1309 
1310 		/* workaround for h/w bug in System MMU v3.3 */
1311 		exynos_iommu_set_pte(ent, ZERO_LV2LINK);
1312 		size = SECT_SIZE;
1313 		goto done;
1314 	}
1315 
1316 	if (unlikely(lv1ent_fault(ent))) {
1317 		if (size > SECT_SIZE)
1318 			size = SECT_SIZE;
1319 		goto done;
1320 	}
1321 
1322 	/* lv1ent_page(sent) == true here */
1323 
1324 	ent = page_entry(ent, iova);
1325 
1326 	if (unlikely(lv2ent_fault(ent))) {
1327 		size = SPAGE_SIZE;
1328 		goto done;
1329 	}
1330 
1331 	if (lv2ent_small(ent)) {
1332 		exynos_iommu_set_pte(ent, 0);
1333 		size = SPAGE_SIZE;
1334 		domain->lv2entcnt[lv1ent_offset(iova)] += 1;
1335 		goto done;
1336 	}
1337 
1338 	/* lv1ent_large(ent) == true here */
1339 	if (WARN_ON(size < LPAGE_SIZE)) {
1340 		err_pgsize = LPAGE_SIZE;
1341 		goto err;
1342 	}
1343 
1344 	dma_sync_single_for_cpu(dma_dev, virt_to_phys(ent),
1345 				sizeof(*ent) * SPAGES_PER_LPAGE,
1346 				DMA_TO_DEVICE);
1347 	memset(ent, 0, sizeof(*ent) * SPAGES_PER_LPAGE);
1348 	dma_sync_single_for_device(dma_dev, virt_to_phys(ent),
1349 				   sizeof(*ent) * SPAGES_PER_LPAGE,
1350 				   DMA_TO_DEVICE);
1351 	size = LPAGE_SIZE;
1352 	domain->lv2entcnt[lv1ent_offset(iova)] += SPAGES_PER_LPAGE;
1353 done:
1354 	spin_unlock_irqrestore(&domain->pgtablelock, flags);
1355 
1356 	exynos_iommu_tlb_invalidate_entry(domain, iova, size);
1357 
1358 	return size;
1359 err:
1360 	spin_unlock_irqrestore(&domain->pgtablelock, flags);
1361 
1362 	pr_err("%s: Failed: size(%#zx) @ %#x is smaller than page size %#zx\n",
1363 		__func__, size, iova, err_pgsize);
1364 
1365 	return 0;
1366 }
1367 
1368 static phys_addr_t exynos_iommu_iova_to_phys(struct iommu_domain *iommu_domain,
1369 					  dma_addr_t iova)
1370 {
1371 	struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
1372 	sysmmu_pte_t *entry;
1373 	unsigned long flags;
1374 	phys_addr_t phys = 0;
1375 
1376 	spin_lock_irqsave(&domain->pgtablelock, flags);
1377 
1378 	entry = section_entry(domain->pgtable, iova);
1379 
1380 	if (lv1ent_section(entry)) {
1381 		phys = section_phys(entry) + section_offs(iova);
1382 	} else if (lv1ent_page(entry)) {
1383 		entry = page_entry(entry, iova);
1384 
1385 		if (lv2ent_large(entry))
1386 			phys = lpage_phys(entry) + lpage_offs(iova);
1387 		else if (lv2ent_small(entry))
1388 			phys = spage_phys(entry) + spage_offs(iova);
1389 	}
1390 
1391 	spin_unlock_irqrestore(&domain->pgtablelock, flags);
1392 
1393 	return phys;
1394 }
1395 
1396 static struct iommu_device *exynos_iommu_probe_device(struct device *dev)
1397 {
1398 	struct exynos_iommu_owner *owner = dev_iommu_priv_get(dev);
1399 	struct sysmmu_drvdata *data;
1400 
1401 	if (!has_sysmmu(dev))
1402 		return ERR_PTR(-ENODEV);
1403 
1404 	list_for_each_entry(data, &owner->controllers, owner_node) {
1405 		/*
1406 		 * SYSMMU will be runtime activated via device link
1407 		 * (dependency) to its master device, so there are no
1408 		 * direct calls to pm_runtime_get/put in this driver.
1409 		 */
1410 		data->link = device_link_add(dev, data->sysmmu,
1411 					     DL_FLAG_STATELESS |
1412 					     DL_FLAG_PM_RUNTIME);
1413 	}
1414 
1415 	/* There is always at least one entry, see exynos_iommu_of_xlate() */
1416 	data = list_first_entry(&owner->controllers,
1417 				struct sysmmu_drvdata, owner_node);
1418 
1419 	return &data->iommu;
1420 }
1421 
1422 static void exynos_iommu_release_device(struct device *dev)
1423 {
1424 	struct exynos_iommu_owner *owner = dev_iommu_priv_get(dev);
1425 	struct sysmmu_drvdata *data;
1426 
1427 	WARN_ON(exynos_iommu_identity_attach(&exynos_identity_domain, dev));
1428 
1429 	list_for_each_entry(data, &owner->controllers, owner_node)
1430 		device_link_del(data->link);
1431 }
1432 
1433 static int exynos_iommu_of_xlate(struct device *dev,
1434 				 const struct of_phandle_args *spec)
1435 {
1436 	struct platform_device *sysmmu = of_find_device_by_node(spec->np);
1437 	struct exynos_iommu_owner *owner = dev_iommu_priv_get(dev);
1438 	struct sysmmu_drvdata *data, *entry;
1439 
1440 	if (!sysmmu)
1441 		return -ENODEV;
1442 
1443 	data = platform_get_drvdata(sysmmu);
1444 	if (!data) {
1445 		put_device(&sysmmu->dev);
1446 		return -ENODEV;
1447 	}
1448 
1449 	if (!owner) {
1450 		owner = kzalloc(sizeof(*owner), GFP_KERNEL);
1451 		if (!owner) {
1452 			put_device(&sysmmu->dev);
1453 			return -ENOMEM;
1454 		}
1455 
1456 		INIT_LIST_HEAD(&owner->controllers);
1457 		mutex_init(&owner->rpm_lock);
1458 		owner->domain = &exynos_identity_domain;
1459 		dev_iommu_priv_set(dev, owner);
1460 	}
1461 
1462 	list_for_each_entry(entry, &owner->controllers, owner_node)
1463 		if (entry == data)
1464 			return 0;
1465 
1466 	list_add_tail(&data->owner_node, &owner->controllers);
1467 	data->master = dev;
1468 
1469 	return 0;
1470 }
1471 
1472 static const struct iommu_ops exynos_iommu_ops = {
1473 	.identity_domain = &exynos_identity_domain,
1474 	.domain_alloc_paging = exynos_iommu_domain_alloc_paging,
1475 	.device_group = generic_device_group,
1476 	.probe_device = exynos_iommu_probe_device,
1477 	.release_device = exynos_iommu_release_device,
1478 	.pgsize_bitmap = SECT_SIZE | LPAGE_SIZE | SPAGE_SIZE,
1479 	.of_xlate = exynos_iommu_of_xlate,
1480 	.default_domain_ops = &(const struct iommu_domain_ops) {
1481 		.attach_dev	= exynos_iommu_attach_device,
1482 		.map_pages	= exynos_iommu_map,
1483 		.unmap_pages	= exynos_iommu_unmap,
1484 		.iova_to_phys	= exynos_iommu_iova_to_phys,
1485 		.free		= exynos_iommu_domain_free,
1486 	}
1487 };
1488 
1489 static int __init exynos_iommu_init(void)
1490 {
1491 	struct device_node *np;
1492 	int ret;
1493 
1494 	np = of_find_matching_node(NULL, sysmmu_of_match);
1495 	if (!np)
1496 		return 0;
1497 
1498 	of_node_put(np);
1499 
1500 	lv2table_kmem_cache = kmem_cache_create("exynos-iommu-lv2table",
1501 				LV2TABLE_SIZE, LV2TABLE_SIZE, 0, NULL);
1502 	if (!lv2table_kmem_cache) {
1503 		pr_err("%s: Failed to create kmem cache\n", __func__);
1504 		return -ENOMEM;
1505 	}
1506 
1507 	zero_lv2_table = kmem_cache_zalloc(lv2table_kmem_cache, GFP_KERNEL);
1508 	if (zero_lv2_table == NULL) {
1509 		pr_err("%s: Failed to allocate zero level2 page table\n",
1510 			__func__);
1511 		ret = -ENOMEM;
1512 		goto err_zero_lv2;
1513 	}
1514 
1515 	ret = platform_driver_register(&exynos_sysmmu_driver);
1516 	if (ret) {
1517 		pr_err("%s: Failed to register driver\n", __func__);
1518 		goto err_reg_driver;
1519 	}
1520 
1521 	return 0;
1522 err_reg_driver:
1523 	kmem_cache_free(lv2table_kmem_cache, zero_lv2_table);
1524 err_zero_lv2:
1525 	kmem_cache_destroy(lv2table_kmem_cache);
1526 	return ret;
1527 }
1528 core_initcall(exynos_iommu_init);
1529