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_iommu.h>
21 #include <linux/of_platform.h>
22 #include <linux/platform_device.h>
23 #include <linux/pm_runtime.h>
24 #include <linux/slab.h>
25 #include <linux/dma-iommu.h>
26
27 typedef u32 sysmmu_iova_t;
28 typedef u32 sysmmu_pte_t;
29
30 /* We do not consider super section mapping (16MB) */
31 #define SECT_ORDER 20
32 #define LPAGE_ORDER 16
33 #define SPAGE_ORDER 12
34
35 #define SECT_SIZE (1 << SECT_ORDER)
36 #define LPAGE_SIZE (1 << LPAGE_ORDER)
37 #define SPAGE_SIZE (1 << SPAGE_ORDER)
38
39 #define SECT_MASK (~(SECT_SIZE - 1))
40 #define LPAGE_MASK (~(LPAGE_SIZE - 1))
41 #define SPAGE_MASK (~(SPAGE_SIZE - 1))
42
43 #define lv1ent_fault(sent) ((*(sent) == ZERO_LV2LINK) || \
44 ((*(sent) & 3) == 0) || ((*(sent) & 3) == 3))
45 #define lv1ent_zero(sent) (*(sent) == ZERO_LV2LINK)
46 #define lv1ent_page_zero(sent) ((*(sent) & 3) == 1)
47 #define lv1ent_page(sent) ((*(sent) != ZERO_LV2LINK) && \
48 ((*(sent) & 3) == 1))
49 #define lv1ent_section(sent) ((*(sent) & 3) == 2)
50
51 #define lv2ent_fault(pent) ((*(pent) & 3) == 0)
52 #define lv2ent_small(pent) ((*(pent) & 2) == 2)
53 #define lv2ent_large(pent) ((*(pent) & 3) == 1)
54
55 /*
56 * v1.x - v3.x SYSMMU supports 32bit physical and 32bit virtual address spaces
57 * v5.0 introduced support for 36bit physical address space by shifting
58 * all page entry values by 4 bits.
59 * All SYSMMU controllers in the system support the address spaces of the same
60 * size, so PG_ENT_SHIFT can be initialized on first SYSMMU probe to proper
61 * value (0 or 4).
62 */
63 static short PG_ENT_SHIFT = -1;
64 #define SYSMMU_PG_ENT_SHIFT 0
65 #define SYSMMU_V5_PG_ENT_SHIFT 4
66
67 static const sysmmu_pte_t *LV1_PROT;
68 static const sysmmu_pte_t SYSMMU_LV1_PROT[] = {
69 ((0 << 15) | (0 << 10)), /* no access */
70 ((1 << 15) | (1 << 10)), /* IOMMU_READ only */
71 ((0 << 15) | (1 << 10)), /* IOMMU_WRITE not supported, use read/write */
72 ((0 << 15) | (1 << 10)), /* IOMMU_READ | IOMMU_WRITE */
73 };
74 static const sysmmu_pte_t SYSMMU_V5_LV1_PROT[] = {
75 (0 << 4), /* no access */
76 (1 << 4), /* IOMMU_READ only */
77 (2 << 4), /* IOMMU_WRITE only */
78 (3 << 4), /* IOMMU_READ | IOMMU_WRITE */
79 };
80
81 static const sysmmu_pte_t *LV2_PROT;
82 static const sysmmu_pte_t SYSMMU_LV2_PROT[] = {
83 ((0 << 9) | (0 << 4)), /* no access */
84 ((1 << 9) | (1 << 4)), /* IOMMU_READ only */
85 ((0 << 9) | (1 << 4)), /* IOMMU_WRITE not supported, use read/write */
86 ((0 << 9) | (1 << 4)), /* IOMMU_READ | IOMMU_WRITE */
87 };
88 static const sysmmu_pte_t SYSMMU_V5_LV2_PROT[] = {
89 (0 << 2), /* no access */
90 (1 << 2), /* IOMMU_READ only */
91 (2 << 2), /* IOMMU_WRITE only */
92 (3 << 2), /* IOMMU_READ | IOMMU_WRITE */
93 };
94
95 #define SYSMMU_SUPPORTED_PROT_BITS (IOMMU_READ | IOMMU_WRITE)
96
97 #define sect_to_phys(ent) (((phys_addr_t) ent) << PG_ENT_SHIFT)
98 #define section_phys(sent) (sect_to_phys(*(sent)) & SECT_MASK)
99 #define section_offs(iova) (iova & (SECT_SIZE - 1))
100 #define lpage_phys(pent) (sect_to_phys(*(pent)) & LPAGE_MASK)
101 #define lpage_offs(iova) (iova & (LPAGE_SIZE - 1))
102 #define spage_phys(pent) (sect_to_phys(*(pent)) & SPAGE_MASK)
103 #define spage_offs(iova) (iova & (SPAGE_SIZE - 1))
104
105 #define NUM_LV1ENTRIES 4096
106 #define NUM_LV2ENTRIES (SECT_SIZE / SPAGE_SIZE)
107
lv1ent_offset(sysmmu_iova_t iova)108 static u32 lv1ent_offset(sysmmu_iova_t iova)
109 {
110 return iova >> SECT_ORDER;
111 }
112
lv2ent_offset(sysmmu_iova_t iova)113 static u32 lv2ent_offset(sysmmu_iova_t iova)
114 {
115 return (iova >> SPAGE_ORDER) & (NUM_LV2ENTRIES - 1);
116 }
117
118 #define LV1TABLE_SIZE (NUM_LV1ENTRIES * sizeof(sysmmu_pte_t))
119 #define LV2TABLE_SIZE (NUM_LV2ENTRIES * sizeof(sysmmu_pte_t))
120
121 #define SPAGES_PER_LPAGE (LPAGE_SIZE / SPAGE_SIZE)
122 #define lv2table_base(sent) (sect_to_phys(*(sent) & 0xFFFFFFC0))
123
124 #define mk_lv1ent_sect(pa, prot) ((pa >> PG_ENT_SHIFT) | LV1_PROT[prot] | 2)
125 #define mk_lv1ent_page(pa) ((pa >> PG_ENT_SHIFT) | 1)
126 #define mk_lv2ent_lpage(pa, prot) ((pa >> PG_ENT_SHIFT) | LV2_PROT[prot] | 1)
127 #define mk_lv2ent_spage(pa, prot) ((pa >> PG_ENT_SHIFT) | LV2_PROT[prot] | 2)
128
129 #define CTRL_ENABLE 0x5
130 #define CTRL_BLOCK 0x7
131 #define CTRL_DISABLE 0x0
132
133 #define CFG_LRU 0x1
134 #define CFG_EAP (1 << 2)
135 #define CFG_QOS(n) ((n & 0xF) << 7)
136 #define CFG_ACGEN (1 << 24) /* System MMU 3.3 only */
137 #define CFG_SYSSEL (1 << 22) /* System MMU 3.2 only */
138 #define CFG_FLPDCACHE (1 << 20) /* System MMU 3.2+ only */
139
140 /* common registers */
141 #define REG_MMU_CTRL 0x000
142 #define REG_MMU_CFG 0x004
143 #define REG_MMU_STATUS 0x008
144 #define REG_MMU_VERSION 0x034
145
146 #define MMU_MAJ_VER(val) ((val) >> 7)
147 #define MMU_MIN_VER(val) ((val) & 0x7F)
148 #define MMU_RAW_VER(reg) (((reg) >> 21) & ((1 << 11) - 1)) /* 11 bits */
149
150 #define MAKE_MMU_VER(maj, min) ((((maj) & 0xF) << 7) | ((min) & 0x7F))
151
152 /* v1.x - v3.x registers */
153 #define REG_MMU_FLUSH 0x00C
154 #define REG_MMU_FLUSH_ENTRY 0x010
155 #define REG_PT_BASE_ADDR 0x014
156 #define REG_INT_STATUS 0x018
157 #define REG_INT_CLEAR 0x01C
158
159 #define REG_PAGE_FAULT_ADDR 0x024
160 #define REG_AW_FAULT_ADDR 0x028
161 #define REG_AR_FAULT_ADDR 0x02C
162 #define REG_DEFAULT_SLAVE_ADDR 0x030
163
164 /* v5.x registers */
165 #define REG_V5_PT_BASE_PFN 0x00C
166 #define REG_V5_MMU_FLUSH_ALL 0x010
167 #define REG_V5_MMU_FLUSH_ENTRY 0x014
168 #define REG_V5_MMU_FLUSH_RANGE 0x018
169 #define REG_V5_MMU_FLUSH_START 0x020
170 #define REG_V5_MMU_FLUSH_END 0x024
171 #define REG_V5_INT_STATUS 0x060
172 #define REG_V5_INT_CLEAR 0x064
173 #define REG_V5_FAULT_AR_VA 0x070
174 #define REG_V5_FAULT_AW_VA 0x080
175
176 #define has_sysmmu(dev) (dev->archdata.iommu != NULL)
177
178 static struct device *dma_dev;
179 static struct kmem_cache *lv2table_kmem_cache;
180 static sysmmu_pte_t *zero_lv2_table;
181 #define ZERO_LV2LINK mk_lv1ent_page(virt_to_phys(zero_lv2_table))
182
section_entry(sysmmu_pte_t * pgtable,sysmmu_iova_t iova)183 static sysmmu_pte_t *section_entry(sysmmu_pte_t *pgtable, sysmmu_iova_t iova)
184 {
185 return pgtable + lv1ent_offset(iova);
186 }
187
page_entry(sysmmu_pte_t * sent,sysmmu_iova_t iova)188 static sysmmu_pte_t *page_entry(sysmmu_pte_t *sent, sysmmu_iova_t iova)
189 {
190 return (sysmmu_pte_t *)phys_to_virt(
191 lv2table_base(sent)) + lv2ent_offset(iova);
192 }
193
194 /*
195 * IOMMU fault information register
196 */
197 struct sysmmu_fault_info {
198 unsigned int bit; /* bit number in STATUS register */
199 unsigned short addr_reg; /* register to read VA fault address */
200 const char *name; /* human readable fault name */
201 unsigned int type; /* fault type for report_iommu_fault */
202 };
203
204 static const struct sysmmu_fault_info sysmmu_faults[] = {
205 { 0, REG_PAGE_FAULT_ADDR, "PAGE", IOMMU_FAULT_READ },
206 { 1, REG_AR_FAULT_ADDR, "AR MULTI-HIT", IOMMU_FAULT_READ },
207 { 2, REG_AW_FAULT_ADDR, "AW MULTI-HIT", IOMMU_FAULT_WRITE },
208 { 3, REG_DEFAULT_SLAVE_ADDR, "BUS ERROR", IOMMU_FAULT_READ },
209 { 4, REG_AR_FAULT_ADDR, "AR SECURITY PROTECTION", IOMMU_FAULT_READ },
210 { 5, REG_AR_FAULT_ADDR, "AR ACCESS PROTECTION", IOMMU_FAULT_READ },
211 { 6, REG_AW_FAULT_ADDR, "AW SECURITY PROTECTION", IOMMU_FAULT_WRITE },
212 { 7, REG_AW_FAULT_ADDR, "AW ACCESS PROTECTION", IOMMU_FAULT_WRITE },
213 };
214
215 static const struct sysmmu_fault_info sysmmu_v5_faults[] = {
216 { 0, REG_V5_FAULT_AR_VA, "AR PTW", IOMMU_FAULT_READ },
217 { 1, REG_V5_FAULT_AR_VA, "AR PAGE", IOMMU_FAULT_READ },
218 { 2, REG_V5_FAULT_AR_VA, "AR MULTI-HIT", IOMMU_FAULT_READ },
219 { 3, REG_V5_FAULT_AR_VA, "AR ACCESS PROTECTION", IOMMU_FAULT_READ },
220 { 4, REG_V5_FAULT_AR_VA, "AR SECURITY PROTECTION", IOMMU_FAULT_READ },
221 { 16, REG_V5_FAULT_AW_VA, "AW PTW", IOMMU_FAULT_WRITE },
222 { 17, REG_V5_FAULT_AW_VA, "AW PAGE", IOMMU_FAULT_WRITE },
223 { 18, REG_V5_FAULT_AW_VA, "AW MULTI-HIT", IOMMU_FAULT_WRITE },
224 { 19, REG_V5_FAULT_AW_VA, "AW ACCESS PROTECTION", IOMMU_FAULT_WRITE },
225 { 20, REG_V5_FAULT_AW_VA, "AW SECURITY PROTECTION", IOMMU_FAULT_WRITE },
226 };
227
228 /*
229 * This structure is attached to dev.archdata.iommu 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 /*
256 * This structure hold all data of a single SYSMMU controller, this includes
257 * hw resources like registers and clocks, pointers and list nodes to connect
258 * it to all other structures, internal state and parameters read from device
259 * tree. It is usually referenced by 'data' pointer.
260 */
261 struct sysmmu_drvdata {
262 struct device *sysmmu; /* SYSMMU controller device */
263 struct device *master; /* master device (owner) */
264 struct device_link *link; /* runtime PM link to master */
265 void __iomem *sfrbase; /* our registers */
266 struct clk *clk; /* SYSMMU's clock */
267 struct clk *aclk; /* SYSMMU's aclk clock */
268 struct clk *pclk; /* SYSMMU's pclk clock */
269 struct clk *clk_master; /* master's device clock */
270 spinlock_t lock; /* lock for modyfying state */
271 bool active; /* current status */
272 struct exynos_iommu_domain *domain; /* domain we belong to */
273 struct list_head domain_node; /* node for domain clients list */
274 struct list_head owner_node; /* node for owner controllers list */
275 phys_addr_t pgtable; /* assigned page table structure */
276 unsigned int version; /* our version */
277
278 struct iommu_device iommu; /* IOMMU core handle */
279 };
280
to_exynos_domain(struct iommu_domain * dom)281 static struct exynos_iommu_domain *to_exynos_domain(struct iommu_domain *dom)
282 {
283 return container_of(dom, struct exynos_iommu_domain, domain);
284 }
285
sysmmu_unblock(struct sysmmu_drvdata * data)286 static void sysmmu_unblock(struct sysmmu_drvdata *data)
287 {
288 writel(CTRL_ENABLE, data->sfrbase + REG_MMU_CTRL);
289 }
290
sysmmu_block(struct sysmmu_drvdata * data)291 static bool sysmmu_block(struct sysmmu_drvdata *data)
292 {
293 int i = 120;
294
295 writel(CTRL_BLOCK, data->sfrbase + REG_MMU_CTRL);
296 while ((i > 0) && !(readl(data->sfrbase + REG_MMU_STATUS) & 1))
297 --i;
298
299 if (!(readl(data->sfrbase + REG_MMU_STATUS) & 1)) {
300 sysmmu_unblock(data);
301 return false;
302 }
303
304 return true;
305 }
306
__sysmmu_tlb_invalidate(struct sysmmu_drvdata * data)307 static void __sysmmu_tlb_invalidate(struct sysmmu_drvdata *data)
308 {
309 if (MMU_MAJ_VER(data->version) < 5)
310 writel(0x1, data->sfrbase + REG_MMU_FLUSH);
311 else
312 writel(0x1, data->sfrbase + REG_V5_MMU_FLUSH_ALL);
313 }
314
__sysmmu_tlb_invalidate_entry(struct sysmmu_drvdata * data,sysmmu_iova_t iova,unsigned int num_inv)315 static void __sysmmu_tlb_invalidate_entry(struct sysmmu_drvdata *data,
316 sysmmu_iova_t iova, unsigned int num_inv)
317 {
318 unsigned int i;
319
320 if (MMU_MAJ_VER(data->version) < 5) {
321 for (i = 0; i < num_inv; i++) {
322 writel((iova & SPAGE_MASK) | 1,
323 data->sfrbase + REG_MMU_FLUSH_ENTRY);
324 iova += SPAGE_SIZE;
325 }
326 } else {
327 if (num_inv == 1) {
328 writel((iova & SPAGE_MASK) | 1,
329 data->sfrbase + REG_V5_MMU_FLUSH_ENTRY);
330 } else {
331 writel((iova & SPAGE_MASK),
332 data->sfrbase + REG_V5_MMU_FLUSH_START);
333 writel((iova & SPAGE_MASK) + (num_inv - 1) * SPAGE_SIZE,
334 data->sfrbase + REG_V5_MMU_FLUSH_END);
335 writel(1, data->sfrbase + REG_V5_MMU_FLUSH_RANGE);
336 }
337 }
338 }
339
__sysmmu_set_ptbase(struct sysmmu_drvdata * data,phys_addr_t pgd)340 static void __sysmmu_set_ptbase(struct sysmmu_drvdata *data, phys_addr_t pgd)
341 {
342 if (MMU_MAJ_VER(data->version) < 5)
343 writel(pgd, data->sfrbase + REG_PT_BASE_ADDR);
344 else
345 writel(pgd >> PAGE_SHIFT,
346 data->sfrbase + REG_V5_PT_BASE_PFN);
347
348 __sysmmu_tlb_invalidate(data);
349 }
350
__sysmmu_enable_clocks(struct sysmmu_drvdata * data)351 static void __sysmmu_enable_clocks(struct sysmmu_drvdata *data)
352 {
353 BUG_ON(clk_prepare_enable(data->clk_master));
354 BUG_ON(clk_prepare_enable(data->clk));
355 BUG_ON(clk_prepare_enable(data->pclk));
356 BUG_ON(clk_prepare_enable(data->aclk));
357 }
358
__sysmmu_disable_clocks(struct sysmmu_drvdata * data)359 static void __sysmmu_disable_clocks(struct sysmmu_drvdata *data)
360 {
361 clk_disable_unprepare(data->aclk);
362 clk_disable_unprepare(data->pclk);
363 clk_disable_unprepare(data->clk);
364 clk_disable_unprepare(data->clk_master);
365 }
366
__sysmmu_get_version(struct sysmmu_drvdata * data)367 static void __sysmmu_get_version(struct sysmmu_drvdata *data)
368 {
369 u32 ver;
370
371 __sysmmu_enable_clocks(data);
372
373 ver = readl(data->sfrbase + REG_MMU_VERSION);
374
375 /* controllers on some SoCs don't report proper version */
376 if (ver == 0x80000001u)
377 data->version = MAKE_MMU_VER(1, 0);
378 else
379 data->version = MMU_RAW_VER(ver);
380
381 dev_dbg(data->sysmmu, "hardware version: %d.%d\n",
382 MMU_MAJ_VER(data->version), MMU_MIN_VER(data->version));
383
384 __sysmmu_disable_clocks(data);
385 }
386
show_fault_information(struct sysmmu_drvdata * data,const struct sysmmu_fault_info * finfo,sysmmu_iova_t fault_addr)387 static void show_fault_information(struct sysmmu_drvdata *data,
388 const struct sysmmu_fault_info *finfo,
389 sysmmu_iova_t fault_addr)
390 {
391 sysmmu_pte_t *ent;
392
393 dev_err(data->sysmmu, "%s: %s FAULT occurred at %#x\n",
394 dev_name(data->master), finfo->name, fault_addr);
395 dev_dbg(data->sysmmu, "Page table base: %pa\n", &data->pgtable);
396 ent = section_entry(phys_to_virt(data->pgtable), fault_addr);
397 dev_dbg(data->sysmmu, "\tLv1 entry: %#x\n", *ent);
398 if (lv1ent_page(ent)) {
399 ent = page_entry(ent, fault_addr);
400 dev_dbg(data->sysmmu, "\t Lv2 entry: %#x\n", *ent);
401 }
402 }
403
exynos_sysmmu_irq(int irq,void * dev_id)404 static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
405 {
406 /* SYSMMU is in blocked state when interrupt occurred. */
407 struct sysmmu_drvdata *data = dev_id;
408 const struct sysmmu_fault_info *finfo;
409 unsigned int i, n, itype;
410 sysmmu_iova_t fault_addr = -1;
411 unsigned short reg_status, reg_clear;
412 int ret = -ENOSYS;
413
414 WARN_ON(!data->active);
415
416 if (MMU_MAJ_VER(data->version) < 5) {
417 reg_status = REG_INT_STATUS;
418 reg_clear = REG_INT_CLEAR;
419 finfo = sysmmu_faults;
420 n = ARRAY_SIZE(sysmmu_faults);
421 } else {
422 reg_status = REG_V5_INT_STATUS;
423 reg_clear = REG_V5_INT_CLEAR;
424 finfo = sysmmu_v5_faults;
425 n = ARRAY_SIZE(sysmmu_v5_faults);
426 }
427
428 spin_lock(&data->lock);
429
430 clk_enable(data->clk_master);
431
432 itype = __ffs(readl(data->sfrbase + reg_status));
433 for (i = 0; i < n; i++, finfo++)
434 if (finfo->bit == itype)
435 break;
436 /* unknown/unsupported fault */
437 BUG_ON(i == n);
438
439 /* print debug message */
440 fault_addr = readl(data->sfrbase + finfo->addr_reg);
441 show_fault_information(data, finfo, fault_addr);
442
443 if (data->domain)
444 ret = report_iommu_fault(&data->domain->domain,
445 data->master, fault_addr, finfo->type);
446 /* fault is not recovered by fault handler */
447 BUG_ON(ret != 0);
448
449 writel(1 << itype, data->sfrbase + reg_clear);
450
451 sysmmu_unblock(data);
452
453 clk_disable(data->clk_master);
454
455 spin_unlock(&data->lock);
456
457 return IRQ_HANDLED;
458 }
459
__sysmmu_disable(struct sysmmu_drvdata * data)460 static void __sysmmu_disable(struct sysmmu_drvdata *data)
461 {
462 unsigned long flags;
463
464 clk_enable(data->clk_master);
465
466 spin_lock_irqsave(&data->lock, flags);
467 writel(CTRL_DISABLE, data->sfrbase + REG_MMU_CTRL);
468 writel(0, data->sfrbase + REG_MMU_CFG);
469 data->active = false;
470 spin_unlock_irqrestore(&data->lock, flags);
471
472 __sysmmu_disable_clocks(data);
473 }
474
__sysmmu_init_config(struct sysmmu_drvdata * data)475 static void __sysmmu_init_config(struct sysmmu_drvdata *data)
476 {
477 unsigned int cfg;
478
479 if (data->version <= MAKE_MMU_VER(3, 1))
480 cfg = CFG_LRU | CFG_QOS(15);
481 else if (data->version <= MAKE_MMU_VER(3, 2))
482 cfg = CFG_LRU | CFG_QOS(15) | CFG_FLPDCACHE | CFG_SYSSEL;
483 else
484 cfg = CFG_QOS(15) | CFG_FLPDCACHE | CFG_ACGEN;
485
486 cfg |= CFG_EAP; /* enable access protection bits check */
487
488 writel(cfg, data->sfrbase + REG_MMU_CFG);
489 }
490
__sysmmu_enable(struct sysmmu_drvdata * data)491 static void __sysmmu_enable(struct sysmmu_drvdata *data)
492 {
493 unsigned long flags;
494
495 __sysmmu_enable_clocks(data);
496
497 spin_lock_irqsave(&data->lock, flags);
498 writel(CTRL_BLOCK, data->sfrbase + REG_MMU_CTRL);
499 __sysmmu_init_config(data);
500 __sysmmu_set_ptbase(data, data->pgtable);
501 writel(CTRL_ENABLE, data->sfrbase + REG_MMU_CTRL);
502 data->active = true;
503 spin_unlock_irqrestore(&data->lock, flags);
504
505 /*
506 * SYSMMU driver keeps master's clock enabled only for the short
507 * time, while accessing the registers. For performing address
508 * translation during DMA transaction it relies on the client
509 * driver to enable it.
510 */
511 clk_disable(data->clk_master);
512 }
513
sysmmu_tlb_invalidate_flpdcache(struct sysmmu_drvdata * data,sysmmu_iova_t iova)514 static void sysmmu_tlb_invalidate_flpdcache(struct sysmmu_drvdata *data,
515 sysmmu_iova_t iova)
516 {
517 unsigned long flags;
518
519 spin_lock_irqsave(&data->lock, flags);
520 if (data->active && data->version >= MAKE_MMU_VER(3, 3)) {
521 clk_enable(data->clk_master);
522 if (sysmmu_block(data)) {
523 if (data->version >= MAKE_MMU_VER(5, 0))
524 __sysmmu_tlb_invalidate(data);
525 else
526 __sysmmu_tlb_invalidate_entry(data, iova, 1);
527 sysmmu_unblock(data);
528 }
529 clk_disable(data->clk_master);
530 }
531 spin_unlock_irqrestore(&data->lock, flags);
532 }
533
sysmmu_tlb_invalidate_entry(struct sysmmu_drvdata * data,sysmmu_iova_t iova,size_t size)534 static void sysmmu_tlb_invalidate_entry(struct sysmmu_drvdata *data,
535 sysmmu_iova_t iova, size_t size)
536 {
537 unsigned long flags;
538
539 spin_lock_irqsave(&data->lock, flags);
540 if (data->active) {
541 unsigned int num_inv = 1;
542
543 clk_enable(data->clk_master);
544
545 /*
546 * L2TLB invalidation required
547 * 4KB page: 1 invalidation
548 * 64KB page: 16 invalidations
549 * 1MB page: 64 invalidations
550 * because it is set-associative TLB
551 * with 8-way and 64 sets.
552 * 1MB page can be cached in one of all sets.
553 * 64KB page can be one of 16 consecutive sets.
554 */
555 if (MMU_MAJ_VER(data->version) == 2)
556 num_inv = min_t(unsigned int, size / PAGE_SIZE, 64);
557
558 if (sysmmu_block(data)) {
559 __sysmmu_tlb_invalidate_entry(data, iova, num_inv);
560 sysmmu_unblock(data);
561 }
562 clk_disable(data->clk_master);
563 }
564 spin_unlock_irqrestore(&data->lock, flags);
565 }
566
567 static const struct iommu_ops exynos_iommu_ops;
568
exynos_sysmmu_probe(struct platform_device * pdev)569 static int exynos_sysmmu_probe(struct platform_device *pdev)
570 {
571 int irq, ret;
572 struct device *dev = &pdev->dev;
573 struct sysmmu_drvdata *data;
574 struct resource *res;
575
576 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
577 if (!data)
578 return -ENOMEM;
579
580 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
581 data->sfrbase = devm_ioremap_resource(dev, res);
582 if (IS_ERR(data->sfrbase))
583 return PTR_ERR(data->sfrbase);
584
585 irq = platform_get_irq(pdev, 0);
586 if (irq <= 0)
587 return irq;
588
589 ret = devm_request_irq(dev, irq, exynos_sysmmu_irq, 0,
590 dev_name(dev), data);
591 if (ret) {
592 dev_err(dev, "Unabled to register handler of irq %d\n", irq);
593 return ret;
594 }
595
596 data->clk = devm_clk_get(dev, "sysmmu");
597 if (PTR_ERR(data->clk) == -ENOENT)
598 data->clk = NULL;
599 else if (IS_ERR(data->clk))
600 return PTR_ERR(data->clk);
601
602 data->aclk = devm_clk_get(dev, "aclk");
603 if (PTR_ERR(data->aclk) == -ENOENT)
604 data->aclk = NULL;
605 else if (IS_ERR(data->aclk))
606 return PTR_ERR(data->aclk);
607
608 data->pclk = devm_clk_get(dev, "pclk");
609 if (PTR_ERR(data->pclk) == -ENOENT)
610 data->pclk = NULL;
611 else if (IS_ERR(data->pclk))
612 return PTR_ERR(data->pclk);
613
614 if (!data->clk && (!data->aclk || !data->pclk)) {
615 dev_err(dev, "Failed to get device clock(s)!\n");
616 return -ENOSYS;
617 }
618
619 data->clk_master = devm_clk_get(dev, "master");
620 if (PTR_ERR(data->clk_master) == -ENOENT)
621 data->clk_master = NULL;
622 else if (IS_ERR(data->clk_master))
623 return PTR_ERR(data->clk_master);
624
625 data->sysmmu = dev;
626 spin_lock_init(&data->lock);
627
628 ret = iommu_device_sysfs_add(&data->iommu, &pdev->dev, NULL,
629 dev_name(data->sysmmu));
630 if (ret)
631 return ret;
632
633 iommu_device_set_ops(&data->iommu, &exynos_iommu_ops);
634 iommu_device_set_fwnode(&data->iommu, &dev->of_node->fwnode);
635
636 ret = iommu_device_register(&data->iommu);
637 if (ret)
638 return ret;
639
640 platform_set_drvdata(pdev, data);
641
642 __sysmmu_get_version(data);
643 if (PG_ENT_SHIFT < 0) {
644 if (MMU_MAJ_VER(data->version) < 5) {
645 PG_ENT_SHIFT = SYSMMU_PG_ENT_SHIFT;
646 LV1_PROT = SYSMMU_LV1_PROT;
647 LV2_PROT = SYSMMU_LV2_PROT;
648 } else {
649 PG_ENT_SHIFT = SYSMMU_V5_PG_ENT_SHIFT;
650 LV1_PROT = SYSMMU_V5_LV1_PROT;
651 LV2_PROT = SYSMMU_V5_LV2_PROT;
652 }
653 }
654
655 /*
656 * use the first registered sysmmu device for performing
657 * dma mapping operations on iommu page tables (cpu cache flush)
658 */
659 if (!dma_dev)
660 dma_dev = &pdev->dev;
661
662 pm_runtime_enable(dev);
663
664 return 0;
665 }
666
exynos_sysmmu_suspend(struct device * dev)667 static int __maybe_unused exynos_sysmmu_suspend(struct device *dev)
668 {
669 struct sysmmu_drvdata *data = dev_get_drvdata(dev);
670 struct device *master = data->master;
671
672 if (master) {
673 struct exynos_iommu_owner *owner = master->archdata.iommu;
674
675 mutex_lock(&owner->rpm_lock);
676 if (data->domain) {
677 dev_dbg(data->sysmmu, "saving state\n");
678 __sysmmu_disable(data);
679 }
680 mutex_unlock(&owner->rpm_lock);
681 }
682 return 0;
683 }
684
exynos_sysmmu_resume(struct device * dev)685 static int __maybe_unused exynos_sysmmu_resume(struct device *dev)
686 {
687 struct sysmmu_drvdata *data = dev_get_drvdata(dev);
688 struct device *master = data->master;
689
690 if (master) {
691 struct exynos_iommu_owner *owner = master->archdata.iommu;
692
693 mutex_lock(&owner->rpm_lock);
694 if (data->domain) {
695 dev_dbg(data->sysmmu, "restoring state\n");
696 __sysmmu_enable(data);
697 }
698 mutex_unlock(&owner->rpm_lock);
699 }
700 return 0;
701 }
702
703 static const struct dev_pm_ops sysmmu_pm_ops = {
704 SET_RUNTIME_PM_OPS(exynos_sysmmu_suspend, exynos_sysmmu_resume, NULL)
705 SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
706 pm_runtime_force_resume)
707 };
708
709 static const struct of_device_id sysmmu_of_match[] = {
710 { .compatible = "samsung,exynos-sysmmu", },
711 { },
712 };
713
714 static struct platform_driver exynos_sysmmu_driver __refdata = {
715 .probe = exynos_sysmmu_probe,
716 .driver = {
717 .name = "exynos-sysmmu",
718 .of_match_table = sysmmu_of_match,
719 .pm = &sysmmu_pm_ops,
720 .suppress_bind_attrs = true,
721 }
722 };
723
update_pte(sysmmu_pte_t * ent,sysmmu_pte_t val)724 static inline void update_pte(sysmmu_pte_t *ent, sysmmu_pte_t val)
725 {
726 dma_sync_single_for_cpu(dma_dev, virt_to_phys(ent), sizeof(*ent),
727 DMA_TO_DEVICE);
728 *ent = cpu_to_le32(val);
729 dma_sync_single_for_device(dma_dev, virt_to_phys(ent), sizeof(*ent),
730 DMA_TO_DEVICE);
731 }
732
exynos_iommu_domain_alloc(unsigned type)733 static struct iommu_domain *exynos_iommu_domain_alloc(unsigned type)
734 {
735 struct exynos_iommu_domain *domain;
736 dma_addr_t handle;
737 int i;
738
739 /* Check if correct PTE offsets are initialized */
740 BUG_ON(PG_ENT_SHIFT < 0 || !dma_dev);
741
742 domain = kzalloc(sizeof(*domain), GFP_KERNEL);
743 if (!domain)
744 return NULL;
745
746 if (type == IOMMU_DOMAIN_DMA) {
747 if (iommu_get_dma_cookie(&domain->domain) != 0)
748 goto err_pgtable;
749 } else if (type != IOMMU_DOMAIN_UNMANAGED) {
750 goto err_pgtable;
751 }
752
753 domain->pgtable = (sysmmu_pte_t *)__get_free_pages(GFP_KERNEL, 2);
754 if (!domain->pgtable)
755 goto err_dma_cookie;
756
757 domain->lv2entcnt = (short *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, 1);
758 if (!domain->lv2entcnt)
759 goto err_counter;
760
761 /* Workaround for System MMU v3.3 to prevent caching 1MiB mapping */
762 for (i = 0; i < NUM_LV1ENTRIES; i++)
763 domain->pgtable[i] = ZERO_LV2LINK;
764
765 handle = dma_map_single(dma_dev, domain->pgtable, LV1TABLE_SIZE,
766 DMA_TO_DEVICE);
767 /* For mapping page table entries we rely on dma == phys */
768 BUG_ON(handle != virt_to_phys(domain->pgtable));
769 if (dma_mapping_error(dma_dev, handle))
770 goto err_lv2ent;
771
772 spin_lock_init(&domain->lock);
773 spin_lock_init(&domain->pgtablelock);
774 INIT_LIST_HEAD(&domain->clients);
775
776 domain->domain.geometry.aperture_start = 0;
777 domain->domain.geometry.aperture_end = ~0UL;
778 domain->domain.geometry.force_aperture = true;
779
780 return &domain->domain;
781
782 err_lv2ent:
783 free_pages((unsigned long)domain->lv2entcnt, 1);
784 err_counter:
785 free_pages((unsigned long)domain->pgtable, 2);
786 err_dma_cookie:
787 if (type == IOMMU_DOMAIN_DMA)
788 iommu_put_dma_cookie(&domain->domain);
789 err_pgtable:
790 kfree(domain);
791 return NULL;
792 }
793
exynos_iommu_domain_free(struct iommu_domain * iommu_domain)794 static void exynos_iommu_domain_free(struct iommu_domain *iommu_domain)
795 {
796 struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
797 struct sysmmu_drvdata *data, *next;
798 unsigned long flags;
799 int i;
800
801 WARN_ON(!list_empty(&domain->clients));
802
803 spin_lock_irqsave(&domain->lock, flags);
804
805 list_for_each_entry_safe(data, next, &domain->clients, domain_node) {
806 spin_lock(&data->lock);
807 __sysmmu_disable(data);
808 data->pgtable = 0;
809 data->domain = NULL;
810 list_del_init(&data->domain_node);
811 spin_unlock(&data->lock);
812 }
813
814 spin_unlock_irqrestore(&domain->lock, flags);
815
816 if (iommu_domain->type == IOMMU_DOMAIN_DMA)
817 iommu_put_dma_cookie(iommu_domain);
818
819 dma_unmap_single(dma_dev, virt_to_phys(domain->pgtable), LV1TABLE_SIZE,
820 DMA_TO_DEVICE);
821
822 for (i = 0; i < NUM_LV1ENTRIES; i++)
823 if (lv1ent_page(domain->pgtable + i)) {
824 phys_addr_t base = lv2table_base(domain->pgtable + i);
825
826 dma_unmap_single(dma_dev, base, LV2TABLE_SIZE,
827 DMA_TO_DEVICE);
828 kmem_cache_free(lv2table_kmem_cache,
829 phys_to_virt(base));
830 }
831
832 free_pages((unsigned long)domain->pgtable, 2);
833 free_pages((unsigned long)domain->lv2entcnt, 1);
834 kfree(domain);
835 }
836
exynos_iommu_detach_device(struct iommu_domain * iommu_domain,struct device * dev)837 static void exynos_iommu_detach_device(struct iommu_domain *iommu_domain,
838 struct device *dev)
839 {
840 struct exynos_iommu_owner *owner = dev->archdata.iommu;
841 struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
842 phys_addr_t pagetable = virt_to_phys(domain->pgtable);
843 struct sysmmu_drvdata *data, *next;
844 unsigned long flags;
845
846 if (!has_sysmmu(dev) || owner->domain != iommu_domain)
847 return;
848
849 mutex_lock(&owner->rpm_lock);
850
851 list_for_each_entry(data, &owner->controllers, owner_node) {
852 pm_runtime_get_noresume(data->sysmmu);
853 if (pm_runtime_active(data->sysmmu))
854 __sysmmu_disable(data);
855 pm_runtime_put(data->sysmmu);
856 }
857
858 spin_lock_irqsave(&domain->lock, flags);
859 list_for_each_entry_safe(data, next, &domain->clients, domain_node) {
860 spin_lock(&data->lock);
861 data->pgtable = 0;
862 data->domain = NULL;
863 list_del_init(&data->domain_node);
864 spin_unlock(&data->lock);
865 }
866 owner->domain = NULL;
867 spin_unlock_irqrestore(&domain->lock, flags);
868
869 mutex_unlock(&owner->rpm_lock);
870
871 dev_dbg(dev, "%s: Detached IOMMU with pgtable %pa\n", __func__,
872 &pagetable);
873 }
874
exynos_iommu_attach_device(struct iommu_domain * iommu_domain,struct device * dev)875 static int exynos_iommu_attach_device(struct iommu_domain *iommu_domain,
876 struct device *dev)
877 {
878 struct exynos_iommu_owner *owner = dev->archdata.iommu;
879 struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
880 struct sysmmu_drvdata *data;
881 phys_addr_t pagetable = virt_to_phys(domain->pgtable);
882 unsigned long flags;
883
884 if (!has_sysmmu(dev))
885 return -ENODEV;
886
887 if (owner->domain)
888 exynos_iommu_detach_device(owner->domain, dev);
889
890 mutex_lock(&owner->rpm_lock);
891
892 spin_lock_irqsave(&domain->lock, flags);
893 list_for_each_entry(data, &owner->controllers, owner_node) {
894 spin_lock(&data->lock);
895 data->pgtable = pagetable;
896 data->domain = domain;
897 list_add_tail(&data->domain_node, &domain->clients);
898 spin_unlock(&data->lock);
899 }
900 owner->domain = iommu_domain;
901 spin_unlock_irqrestore(&domain->lock, flags);
902
903 list_for_each_entry(data, &owner->controllers, owner_node) {
904 pm_runtime_get_noresume(data->sysmmu);
905 if (pm_runtime_active(data->sysmmu))
906 __sysmmu_enable(data);
907 pm_runtime_put(data->sysmmu);
908 }
909
910 mutex_unlock(&owner->rpm_lock);
911
912 dev_dbg(dev, "%s: Attached IOMMU with pgtable %pa\n", __func__,
913 &pagetable);
914
915 return 0;
916 }
917
alloc_lv2entry(struct exynos_iommu_domain * domain,sysmmu_pte_t * sent,sysmmu_iova_t iova,short * pgcounter)918 static sysmmu_pte_t *alloc_lv2entry(struct exynos_iommu_domain *domain,
919 sysmmu_pte_t *sent, sysmmu_iova_t iova, short *pgcounter)
920 {
921 if (lv1ent_section(sent)) {
922 WARN(1, "Trying mapping on %#08x mapped with 1MiB page", iova);
923 return ERR_PTR(-EADDRINUSE);
924 }
925
926 if (lv1ent_fault(sent)) {
927 dma_addr_t handle;
928 sysmmu_pte_t *pent;
929 bool need_flush_flpd_cache = lv1ent_zero(sent);
930
931 pent = kmem_cache_zalloc(lv2table_kmem_cache, GFP_ATOMIC);
932 BUG_ON((uintptr_t)pent & (LV2TABLE_SIZE - 1));
933 if (!pent)
934 return ERR_PTR(-ENOMEM);
935
936 update_pte(sent, mk_lv1ent_page(virt_to_phys(pent)));
937 kmemleak_ignore(pent);
938 *pgcounter = NUM_LV2ENTRIES;
939 handle = dma_map_single(dma_dev, pent, LV2TABLE_SIZE,
940 DMA_TO_DEVICE);
941 if (dma_mapping_error(dma_dev, handle)) {
942 kmem_cache_free(lv2table_kmem_cache, pent);
943 return ERR_PTR(-EADDRINUSE);
944 }
945
946 /*
947 * If pre-fetched SLPD is a faulty SLPD in zero_l2_table,
948 * FLPD cache may cache the address of zero_l2_table. This
949 * function replaces the zero_l2_table with new L2 page table
950 * to write valid mappings.
951 * Accessing the valid area may cause page fault since FLPD
952 * cache may still cache zero_l2_table for the valid area
953 * instead of new L2 page table that has the mapping
954 * information of the valid area.
955 * Thus any replacement of zero_l2_table with other valid L2
956 * page table must involve FLPD cache invalidation for System
957 * MMU v3.3.
958 * FLPD cache invalidation is performed with TLB invalidation
959 * by VPN without blocking. It is safe to invalidate TLB without
960 * blocking because the target address of TLB invalidation is
961 * not currently mapped.
962 */
963 if (need_flush_flpd_cache) {
964 struct sysmmu_drvdata *data;
965
966 spin_lock(&domain->lock);
967 list_for_each_entry(data, &domain->clients, domain_node)
968 sysmmu_tlb_invalidate_flpdcache(data, iova);
969 spin_unlock(&domain->lock);
970 }
971 }
972
973 return page_entry(sent, iova);
974 }
975
lv1set_section(struct exynos_iommu_domain * domain,sysmmu_pte_t * sent,sysmmu_iova_t iova,phys_addr_t paddr,int prot,short * pgcnt)976 static int lv1set_section(struct exynos_iommu_domain *domain,
977 sysmmu_pte_t *sent, sysmmu_iova_t iova,
978 phys_addr_t paddr, int prot, short *pgcnt)
979 {
980 if (lv1ent_section(sent)) {
981 WARN(1, "Trying mapping on 1MiB@%#08x that is mapped",
982 iova);
983 return -EADDRINUSE;
984 }
985
986 if (lv1ent_page(sent)) {
987 if (*pgcnt != NUM_LV2ENTRIES) {
988 WARN(1, "Trying mapping on 1MiB@%#08x that is mapped",
989 iova);
990 return -EADDRINUSE;
991 }
992
993 kmem_cache_free(lv2table_kmem_cache, page_entry(sent, 0));
994 *pgcnt = 0;
995 }
996
997 update_pte(sent, mk_lv1ent_sect(paddr, prot));
998
999 spin_lock(&domain->lock);
1000 if (lv1ent_page_zero(sent)) {
1001 struct sysmmu_drvdata *data;
1002 /*
1003 * Flushing FLPD cache in System MMU v3.3 that may cache a FLPD
1004 * entry by speculative prefetch of SLPD which has no mapping.
1005 */
1006 list_for_each_entry(data, &domain->clients, domain_node)
1007 sysmmu_tlb_invalidate_flpdcache(data, iova);
1008 }
1009 spin_unlock(&domain->lock);
1010
1011 return 0;
1012 }
1013
lv2set_page(sysmmu_pte_t * pent,phys_addr_t paddr,size_t size,int prot,short * pgcnt)1014 static int lv2set_page(sysmmu_pte_t *pent, phys_addr_t paddr, size_t size,
1015 int prot, short *pgcnt)
1016 {
1017 if (size == SPAGE_SIZE) {
1018 if (WARN_ON(!lv2ent_fault(pent)))
1019 return -EADDRINUSE;
1020
1021 update_pte(pent, mk_lv2ent_spage(paddr, prot));
1022 *pgcnt -= 1;
1023 } else { /* size == LPAGE_SIZE */
1024 int i;
1025 dma_addr_t pent_base = virt_to_phys(pent);
1026
1027 dma_sync_single_for_cpu(dma_dev, pent_base,
1028 sizeof(*pent) * SPAGES_PER_LPAGE,
1029 DMA_TO_DEVICE);
1030 for (i = 0; i < SPAGES_PER_LPAGE; i++, pent++) {
1031 if (WARN_ON(!lv2ent_fault(pent))) {
1032 if (i > 0)
1033 memset(pent - i, 0, sizeof(*pent) * i);
1034 return -EADDRINUSE;
1035 }
1036
1037 *pent = mk_lv2ent_lpage(paddr, prot);
1038 }
1039 dma_sync_single_for_device(dma_dev, pent_base,
1040 sizeof(*pent) * SPAGES_PER_LPAGE,
1041 DMA_TO_DEVICE);
1042 *pgcnt -= SPAGES_PER_LPAGE;
1043 }
1044
1045 return 0;
1046 }
1047
1048 /*
1049 * *CAUTION* to the I/O virtual memory managers that support exynos-iommu:
1050 *
1051 * System MMU v3.x has advanced logic to improve address translation
1052 * performance with caching more page table entries by a page table walk.
1053 * However, the logic has a bug that while caching faulty page table entries,
1054 * System MMU reports page fault if the cached fault entry is hit even though
1055 * the fault entry is updated to a valid entry after the entry is cached.
1056 * To prevent caching faulty page table entries which may be updated to valid
1057 * entries later, the virtual memory manager should care about the workaround
1058 * for the problem. The following describes the workaround.
1059 *
1060 * Any two consecutive I/O virtual address regions must have a hole of 128KiB
1061 * at maximum to prevent misbehavior of System MMU 3.x (workaround for h/w bug).
1062 *
1063 * Precisely, any start address of I/O virtual region must be aligned with
1064 * the following sizes for System MMU v3.1 and v3.2.
1065 * System MMU v3.1: 128KiB
1066 * System MMU v3.2: 256KiB
1067 *
1068 * Because System MMU v3.3 caches page table entries more aggressively, it needs
1069 * more workarounds.
1070 * - Any two consecutive I/O virtual regions must have a hole of size larger
1071 * than or equal to 128KiB.
1072 * - Start address of an I/O virtual region must be aligned by 128KiB.
1073 */
exynos_iommu_map(struct iommu_domain * iommu_domain,unsigned long l_iova,phys_addr_t paddr,size_t size,int prot)1074 static int exynos_iommu_map(struct iommu_domain *iommu_domain,
1075 unsigned long l_iova, phys_addr_t paddr, size_t size,
1076 int prot)
1077 {
1078 struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
1079 sysmmu_pte_t *entry;
1080 sysmmu_iova_t iova = (sysmmu_iova_t)l_iova;
1081 unsigned long flags;
1082 int ret = -ENOMEM;
1083
1084 BUG_ON(domain->pgtable == NULL);
1085 prot &= SYSMMU_SUPPORTED_PROT_BITS;
1086
1087 spin_lock_irqsave(&domain->pgtablelock, flags);
1088
1089 entry = section_entry(domain->pgtable, iova);
1090
1091 if (size == SECT_SIZE) {
1092 ret = lv1set_section(domain, entry, iova, paddr, prot,
1093 &domain->lv2entcnt[lv1ent_offset(iova)]);
1094 } else {
1095 sysmmu_pte_t *pent;
1096
1097 pent = alloc_lv2entry(domain, entry, iova,
1098 &domain->lv2entcnt[lv1ent_offset(iova)]);
1099
1100 if (IS_ERR(pent))
1101 ret = PTR_ERR(pent);
1102 else
1103 ret = lv2set_page(pent, paddr, size, prot,
1104 &domain->lv2entcnt[lv1ent_offset(iova)]);
1105 }
1106
1107 if (ret)
1108 pr_err("%s: Failed(%d) to map %#zx bytes @ %#x\n",
1109 __func__, ret, size, iova);
1110
1111 spin_unlock_irqrestore(&domain->pgtablelock, flags);
1112
1113 return ret;
1114 }
1115
exynos_iommu_tlb_invalidate_entry(struct exynos_iommu_domain * domain,sysmmu_iova_t iova,size_t size)1116 static void exynos_iommu_tlb_invalidate_entry(struct exynos_iommu_domain *domain,
1117 sysmmu_iova_t iova, size_t size)
1118 {
1119 struct sysmmu_drvdata *data;
1120 unsigned long flags;
1121
1122 spin_lock_irqsave(&domain->lock, flags);
1123
1124 list_for_each_entry(data, &domain->clients, domain_node)
1125 sysmmu_tlb_invalidate_entry(data, iova, size);
1126
1127 spin_unlock_irqrestore(&domain->lock, flags);
1128 }
1129
exynos_iommu_unmap(struct iommu_domain * iommu_domain,unsigned long l_iova,size_t size,struct iommu_iotlb_gather * gather)1130 static size_t exynos_iommu_unmap(struct iommu_domain *iommu_domain,
1131 unsigned long l_iova, size_t size,
1132 struct iommu_iotlb_gather *gather)
1133 {
1134 struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
1135 sysmmu_iova_t iova = (sysmmu_iova_t)l_iova;
1136 sysmmu_pte_t *ent;
1137 size_t err_pgsize;
1138 unsigned long flags;
1139
1140 BUG_ON(domain->pgtable == NULL);
1141
1142 spin_lock_irqsave(&domain->pgtablelock, flags);
1143
1144 ent = section_entry(domain->pgtable, iova);
1145
1146 if (lv1ent_section(ent)) {
1147 if (WARN_ON(size < SECT_SIZE)) {
1148 err_pgsize = SECT_SIZE;
1149 goto err;
1150 }
1151
1152 /* workaround for h/w bug in System MMU v3.3 */
1153 update_pte(ent, ZERO_LV2LINK);
1154 size = SECT_SIZE;
1155 goto done;
1156 }
1157
1158 if (unlikely(lv1ent_fault(ent))) {
1159 if (size > SECT_SIZE)
1160 size = SECT_SIZE;
1161 goto done;
1162 }
1163
1164 /* lv1ent_page(sent) == true here */
1165
1166 ent = page_entry(ent, iova);
1167
1168 if (unlikely(lv2ent_fault(ent))) {
1169 size = SPAGE_SIZE;
1170 goto done;
1171 }
1172
1173 if (lv2ent_small(ent)) {
1174 update_pte(ent, 0);
1175 size = SPAGE_SIZE;
1176 domain->lv2entcnt[lv1ent_offset(iova)] += 1;
1177 goto done;
1178 }
1179
1180 /* lv1ent_large(ent) == true here */
1181 if (WARN_ON(size < LPAGE_SIZE)) {
1182 err_pgsize = LPAGE_SIZE;
1183 goto err;
1184 }
1185
1186 dma_sync_single_for_cpu(dma_dev, virt_to_phys(ent),
1187 sizeof(*ent) * SPAGES_PER_LPAGE,
1188 DMA_TO_DEVICE);
1189 memset(ent, 0, sizeof(*ent) * SPAGES_PER_LPAGE);
1190 dma_sync_single_for_device(dma_dev, virt_to_phys(ent),
1191 sizeof(*ent) * SPAGES_PER_LPAGE,
1192 DMA_TO_DEVICE);
1193 size = LPAGE_SIZE;
1194 domain->lv2entcnt[lv1ent_offset(iova)] += SPAGES_PER_LPAGE;
1195 done:
1196 spin_unlock_irqrestore(&domain->pgtablelock, flags);
1197
1198 exynos_iommu_tlb_invalidate_entry(domain, iova, size);
1199
1200 return size;
1201 err:
1202 spin_unlock_irqrestore(&domain->pgtablelock, flags);
1203
1204 pr_err("%s: Failed: size(%#zx) @ %#x is smaller than page size %#zx\n",
1205 __func__, size, iova, err_pgsize);
1206
1207 return 0;
1208 }
1209
exynos_iommu_iova_to_phys(struct iommu_domain * iommu_domain,dma_addr_t iova)1210 static phys_addr_t exynos_iommu_iova_to_phys(struct iommu_domain *iommu_domain,
1211 dma_addr_t iova)
1212 {
1213 struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
1214 sysmmu_pte_t *entry;
1215 unsigned long flags;
1216 phys_addr_t phys = 0;
1217
1218 spin_lock_irqsave(&domain->pgtablelock, flags);
1219
1220 entry = section_entry(domain->pgtable, iova);
1221
1222 if (lv1ent_section(entry)) {
1223 phys = section_phys(entry) + section_offs(iova);
1224 } else if (lv1ent_page(entry)) {
1225 entry = page_entry(entry, iova);
1226
1227 if (lv2ent_large(entry))
1228 phys = lpage_phys(entry) + lpage_offs(iova);
1229 else if (lv2ent_small(entry))
1230 phys = spage_phys(entry) + spage_offs(iova);
1231 }
1232
1233 spin_unlock_irqrestore(&domain->pgtablelock, flags);
1234
1235 return phys;
1236 }
1237
exynos_iommu_add_device(struct device * dev)1238 static int exynos_iommu_add_device(struct device *dev)
1239 {
1240 struct exynos_iommu_owner *owner = dev->archdata.iommu;
1241 struct sysmmu_drvdata *data;
1242 struct iommu_group *group;
1243
1244 if (!has_sysmmu(dev))
1245 return -ENODEV;
1246
1247 group = iommu_group_get_for_dev(dev);
1248
1249 if (IS_ERR(group))
1250 return PTR_ERR(group);
1251
1252 list_for_each_entry(data, &owner->controllers, owner_node) {
1253 /*
1254 * SYSMMU will be runtime activated via device link
1255 * (dependency) to its master device, so there are no
1256 * direct calls to pm_runtime_get/put in this driver.
1257 */
1258 data->link = device_link_add(dev, data->sysmmu,
1259 DL_FLAG_STATELESS |
1260 DL_FLAG_PM_RUNTIME);
1261 }
1262 iommu_group_put(group);
1263
1264 return 0;
1265 }
1266
exynos_iommu_remove_device(struct device * dev)1267 static void exynos_iommu_remove_device(struct device *dev)
1268 {
1269 struct exynos_iommu_owner *owner = dev->archdata.iommu;
1270 struct sysmmu_drvdata *data;
1271
1272 if (!has_sysmmu(dev))
1273 return;
1274
1275 if (owner->domain) {
1276 struct iommu_group *group = iommu_group_get(dev);
1277
1278 if (group) {
1279 WARN_ON(owner->domain !=
1280 iommu_group_default_domain(group));
1281 exynos_iommu_detach_device(owner->domain, dev);
1282 iommu_group_put(group);
1283 }
1284 }
1285 iommu_group_remove_device(dev);
1286
1287 list_for_each_entry(data, &owner->controllers, owner_node)
1288 device_link_del(data->link);
1289 }
1290
exynos_iommu_of_xlate(struct device * dev,struct of_phandle_args * spec)1291 static int exynos_iommu_of_xlate(struct device *dev,
1292 struct of_phandle_args *spec)
1293 {
1294 struct exynos_iommu_owner *owner = dev->archdata.iommu;
1295 struct platform_device *sysmmu = of_find_device_by_node(spec->np);
1296 struct sysmmu_drvdata *data, *entry;
1297
1298 if (!sysmmu)
1299 return -ENODEV;
1300
1301 data = platform_get_drvdata(sysmmu);
1302 if (!data)
1303 return -ENODEV;
1304
1305 if (!owner) {
1306 owner = kzalloc(sizeof(*owner), GFP_KERNEL);
1307 if (!owner)
1308 return -ENOMEM;
1309
1310 INIT_LIST_HEAD(&owner->controllers);
1311 mutex_init(&owner->rpm_lock);
1312 dev->archdata.iommu = owner;
1313 }
1314
1315 list_for_each_entry(entry, &owner->controllers, owner_node)
1316 if (entry == data)
1317 return 0;
1318
1319 list_add_tail(&data->owner_node, &owner->controllers);
1320 data->master = dev;
1321
1322 return 0;
1323 }
1324
1325 static const struct iommu_ops exynos_iommu_ops = {
1326 .domain_alloc = exynos_iommu_domain_alloc,
1327 .domain_free = exynos_iommu_domain_free,
1328 .attach_dev = exynos_iommu_attach_device,
1329 .detach_dev = exynos_iommu_detach_device,
1330 .map = exynos_iommu_map,
1331 .unmap = exynos_iommu_unmap,
1332 .iova_to_phys = exynos_iommu_iova_to_phys,
1333 .device_group = generic_device_group,
1334 .add_device = exynos_iommu_add_device,
1335 .remove_device = exynos_iommu_remove_device,
1336 .pgsize_bitmap = SECT_SIZE | LPAGE_SIZE | SPAGE_SIZE,
1337 .of_xlate = exynos_iommu_of_xlate,
1338 };
1339
exynos_iommu_init(void)1340 static int __init exynos_iommu_init(void)
1341 {
1342 struct device_node *np;
1343 int ret;
1344
1345 np = of_find_matching_node(NULL, sysmmu_of_match);
1346 if (!np)
1347 return 0;
1348
1349 of_node_put(np);
1350
1351 lv2table_kmem_cache = kmem_cache_create("exynos-iommu-lv2table",
1352 LV2TABLE_SIZE, LV2TABLE_SIZE, 0, NULL);
1353 if (!lv2table_kmem_cache) {
1354 pr_err("%s: Failed to create kmem cache\n", __func__);
1355 return -ENOMEM;
1356 }
1357
1358 ret = platform_driver_register(&exynos_sysmmu_driver);
1359 if (ret) {
1360 pr_err("%s: Failed to register driver\n", __func__);
1361 goto err_reg_driver;
1362 }
1363
1364 zero_lv2_table = kmem_cache_zalloc(lv2table_kmem_cache, GFP_KERNEL);
1365 if (zero_lv2_table == NULL) {
1366 pr_err("%s: Failed to allocate zero level2 page table\n",
1367 __func__);
1368 ret = -ENOMEM;
1369 goto err_zero_lv2;
1370 }
1371
1372 ret = bus_set_iommu(&platform_bus_type, &exynos_iommu_ops);
1373 if (ret) {
1374 pr_err("%s: Failed to register exynos-iommu driver.\n",
1375 __func__);
1376 goto err_set_iommu;
1377 }
1378
1379 return 0;
1380 err_set_iommu:
1381 kmem_cache_free(lv2table_kmem_cache, zero_lv2_table);
1382 err_zero_lv2:
1383 platform_driver_unregister(&exynos_sysmmu_driver);
1384 err_reg_driver:
1385 kmem_cache_destroy(lv2table_kmem_cache);
1386 return ret;
1387 }
1388 core_initcall(exynos_iommu_init);
1389