xref: /openbmc/linux/drivers/iommu/omap-iommu.c (revision 4b4f3acc)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * omap iommu: tlb and pagetable primitives
4  *
5  * Copyright (C) 2008-2010 Nokia Corporation
6  * Copyright (C) 2013-2017 Texas Instruments Incorporated - http://www.ti.com/
7  *
8  * Written by Hiroshi DOYU <Hiroshi.DOYU@nokia.com>,
9  *		Paul Mundt and Toshihiro Kobayashi
10  */
11 
12 #include <linux/dma-mapping.h>
13 #include <linux/err.h>
14 #include <linux/slab.h>
15 #include <linux/interrupt.h>
16 #include <linux/ioport.h>
17 #include <linux/platform_device.h>
18 #include <linux/iommu.h>
19 #include <linux/omap-iommu.h>
20 #include <linux/mutex.h>
21 #include <linux/spinlock.h>
22 #include <linux/io.h>
23 #include <linux/pm_runtime.h>
24 #include <linux/of.h>
25 #include <linux/of_iommu.h>
26 #include <linux/of_irq.h>
27 #include <linux/of_platform.h>
28 #include <linux/regmap.h>
29 #include <linux/mfd/syscon.h>
30 
31 #include <linux/platform_data/iommu-omap.h>
32 
33 #include "omap-iopgtable.h"
34 #include "omap-iommu.h"
35 
36 static const struct iommu_ops omap_iommu_ops;
37 
38 #define to_iommu(dev)							\
39 	((struct omap_iommu *)platform_get_drvdata(to_platform_device(dev)))
40 
41 /* bitmap of the page sizes currently supported */
42 #define OMAP_IOMMU_PGSIZES	(SZ_4K | SZ_64K | SZ_1M | SZ_16M)
43 
44 #define MMU_LOCK_BASE_SHIFT	10
45 #define MMU_LOCK_BASE_MASK	(0x1f << MMU_LOCK_BASE_SHIFT)
46 #define MMU_LOCK_BASE(x)	\
47 	((x & MMU_LOCK_BASE_MASK) >> MMU_LOCK_BASE_SHIFT)
48 
49 #define MMU_LOCK_VICT_SHIFT	4
50 #define MMU_LOCK_VICT_MASK	(0x1f << MMU_LOCK_VICT_SHIFT)
51 #define MMU_LOCK_VICT(x)	\
52 	((x & MMU_LOCK_VICT_MASK) >> MMU_LOCK_VICT_SHIFT)
53 
54 static struct platform_driver omap_iommu_driver;
55 static struct kmem_cache *iopte_cachep;
56 
57 /**
58  * to_omap_domain - Get struct omap_iommu_domain from generic iommu_domain
59  * @dom:	generic iommu domain handle
60  **/
61 static struct omap_iommu_domain *to_omap_domain(struct iommu_domain *dom)
62 {
63 	return container_of(dom, struct omap_iommu_domain, domain);
64 }
65 
66 /**
67  * omap_iommu_save_ctx - Save registers for pm off-mode support
68  * @dev:	client device
69  **/
70 void omap_iommu_save_ctx(struct device *dev)
71 {
72 	struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
73 	struct omap_iommu *obj;
74 	u32 *p;
75 	int i;
76 
77 	if (!arch_data)
78 		return;
79 
80 	while (arch_data->iommu_dev) {
81 		obj = arch_data->iommu_dev;
82 		p = obj->ctx;
83 		for (i = 0; i < (MMU_REG_SIZE / sizeof(u32)); i++) {
84 			p[i] = iommu_read_reg(obj, i * sizeof(u32));
85 			dev_dbg(obj->dev, "%s\t[%02d] %08x\n", __func__, i,
86 				p[i]);
87 		}
88 		arch_data++;
89 	}
90 }
91 EXPORT_SYMBOL_GPL(omap_iommu_save_ctx);
92 
93 /**
94  * omap_iommu_restore_ctx - Restore registers for pm off-mode support
95  * @dev:	client device
96  **/
97 void omap_iommu_restore_ctx(struct device *dev)
98 {
99 	struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
100 	struct omap_iommu *obj;
101 	u32 *p;
102 	int i;
103 
104 	if (!arch_data)
105 		return;
106 
107 	while (arch_data->iommu_dev) {
108 		obj = arch_data->iommu_dev;
109 		p = obj->ctx;
110 		for (i = 0; i < (MMU_REG_SIZE / sizeof(u32)); i++) {
111 			iommu_write_reg(obj, p[i], i * sizeof(u32));
112 			dev_dbg(obj->dev, "%s\t[%02d] %08x\n", __func__, i,
113 				p[i]);
114 		}
115 		arch_data++;
116 	}
117 }
118 EXPORT_SYMBOL_GPL(omap_iommu_restore_ctx);
119 
120 static void dra7_cfg_dspsys_mmu(struct omap_iommu *obj, bool enable)
121 {
122 	u32 val, mask;
123 
124 	if (!obj->syscfg)
125 		return;
126 
127 	mask = (1 << (obj->id * DSP_SYS_MMU_CONFIG_EN_SHIFT));
128 	val = enable ? mask : 0;
129 	regmap_update_bits(obj->syscfg, DSP_SYS_MMU_CONFIG, mask, val);
130 }
131 
132 static void __iommu_set_twl(struct omap_iommu *obj, bool on)
133 {
134 	u32 l = iommu_read_reg(obj, MMU_CNTL);
135 
136 	if (on)
137 		iommu_write_reg(obj, MMU_IRQ_TWL_MASK, MMU_IRQENABLE);
138 	else
139 		iommu_write_reg(obj, MMU_IRQ_TLB_MISS_MASK, MMU_IRQENABLE);
140 
141 	l &= ~MMU_CNTL_MASK;
142 	if (on)
143 		l |= (MMU_CNTL_MMU_EN | MMU_CNTL_TWL_EN);
144 	else
145 		l |= (MMU_CNTL_MMU_EN);
146 
147 	iommu_write_reg(obj, l, MMU_CNTL);
148 }
149 
150 static int omap2_iommu_enable(struct omap_iommu *obj)
151 {
152 	u32 l, pa;
153 
154 	if (!obj->iopgd || !IS_ALIGNED((u32)obj->iopgd,  SZ_16K))
155 		return -EINVAL;
156 
157 	pa = virt_to_phys(obj->iopgd);
158 	if (!IS_ALIGNED(pa, SZ_16K))
159 		return -EINVAL;
160 
161 	l = iommu_read_reg(obj, MMU_REVISION);
162 	dev_info(obj->dev, "%s: version %d.%d\n", obj->name,
163 		 (l >> 4) & 0xf, l & 0xf);
164 
165 	iommu_write_reg(obj, pa, MMU_TTB);
166 
167 	dra7_cfg_dspsys_mmu(obj, true);
168 
169 	if (obj->has_bus_err_back)
170 		iommu_write_reg(obj, MMU_GP_REG_BUS_ERR_BACK_EN, MMU_GP_REG);
171 
172 	__iommu_set_twl(obj, true);
173 
174 	return 0;
175 }
176 
177 static void omap2_iommu_disable(struct omap_iommu *obj)
178 {
179 	u32 l = iommu_read_reg(obj, MMU_CNTL);
180 
181 	l &= ~MMU_CNTL_MASK;
182 	iommu_write_reg(obj, l, MMU_CNTL);
183 	dra7_cfg_dspsys_mmu(obj, false);
184 
185 	dev_dbg(obj->dev, "%s is shutting down\n", obj->name);
186 }
187 
188 static int iommu_enable(struct omap_iommu *obj)
189 {
190 	int err;
191 	struct platform_device *pdev = to_platform_device(obj->dev);
192 	struct iommu_platform_data *pdata = dev_get_platdata(&pdev->dev);
193 
194 	if (pdata && pdata->deassert_reset) {
195 		err = pdata->deassert_reset(pdev, pdata->reset_name);
196 		if (err) {
197 			dev_err(obj->dev, "deassert_reset failed: %d\n", err);
198 			return err;
199 		}
200 	}
201 
202 	pm_runtime_get_sync(obj->dev);
203 
204 	err = omap2_iommu_enable(obj);
205 
206 	return err;
207 }
208 
209 static void iommu_disable(struct omap_iommu *obj)
210 {
211 	struct platform_device *pdev = to_platform_device(obj->dev);
212 	struct iommu_platform_data *pdata = dev_get_platdata(&pdev->dev);
213 
214 	omap2_iommu_disable(obj);
215 
216 	pm_runtime_put_sync(obj->dev);
217 
218 	if (pdata && pdata->assert_reset)
219 		pdata->assert_reset(pdev, pdata->reset_name);
220 }
221 
222 /*
223  *	TLB operations
224  */
225 static u32 iotlb_cr_to_virt(struct cr_regs *cr)
226 {
227 	u32 page_size = cr->cam & MMU_CAM_PGSZ_MASK;
228 	u32 mask = get_cam_va_mask(cr->cam & page_size);
229 
230 	return cr->cam & mask;
231 }
232 
233 static u32 get_iopte_attr(struct iotlb_entry *e)
234 {
235 	u32 attr;
236 
237 	attr = e->mixed << 5;
238 	attr |= e->endian;
239 	attr |= e->elsz >> 3;
240 	attr <<= (((e->pgsz == MMU_CAM_PGSZ_4K) ||
241 			(e->pgsz == MMU_CAM_PGSZ_64K)) ? 0 : 6);
242 	return attr;
243 }
244 
245 static u32 iommu_report_fault(struct omap_iommu *obj, u32 *da)
246 {
247 	u32 status, fault_addr;
248 
249 	status = iommu_read_reg(obj, MMU_IRQSTATUS);
250 	status &= MMU_IRQ_MASK;
251 	if (!status) {
252 		*da = 0;
253 		return 0;
254 	}
255 
256 	fault_addr = iommu_read_reg(obj, MMU_FAULT_AD);
257 	*da = fault_addr;
258 
259 	iommu_write_reg(obj, status, MMU_IRQSTATUS);
260 
261 	return status;
262 }
263 
264 void iotlb_lock_get(struct omap_iommu *obj, struct iotlb_lock *l)
265 {
266 	u32 val;
267 
268 	val = iommu_read_reg(obj, MMU_LOCK);
269 
270 	l->base = MMU_LOCK_BASE(val);
271 	l->vict = MMU_LOCK_VICT(val);
272 }
273 
274 void iotlb_lock_set(struct omap_iommu *obj, struct iotlb_lock *l)
275 {
276 	u32 val;
277 
278 	val = (l->base << MMU_LOCK_BASE_SHIFT);
279 	val |= (l->vict << MMU_LOCK_VICT_SHIFT);
280 
281 	iommu_write_reg(obj, val, MMU_LOCK);
282 }
283 
284 static void iotlb_read_cr(struct omap_iommu *obj, struct cr_regs *cr)
285 {
286 	cr->cam = iommu_read_reg(obj, MMU_READ_CAM);
287 	cr->ram = iommu_read_reg(obj, MMU_READ_RAM);
288 }
289 
290 static void iotlb_load_cr(struct omap_iommu *obj, struct cr_regs *cr)
291 {
292 	iommu_write_reg(obj, cr->cam | MMU_CAM_V, MMU_CAM);
293 	iommu_write_reg(obj, cr->ram, MMU_RAM);
294 
295 	iommu_write_reg(obj, 1, MMU_FLUSH_ENTRY);
296 	iommu_write_reg(obj, 1, MMU_LD_TLB);
297 }
298 
299 /* only used in iotlb iteration for-loop */
300 struct cr_regs __iotlb_read_cr(struct omap_iommu *obj, int n)
301 {
302 	struct cr_regs cr;
303 	struct iotlb_lock l;
304 
305 	iotlb_lock_get(obj, &l);
306 	l.vict = n;
307 	iotlb_lock_set(obj, &l);
308 	iotlb_read_cr(obj, &cr);
309 
310 	return cr;
311 }
312 
313 #ifdef PREFETCH_IOTLB
314 static struct cr_regs *iotlb_alloc_cr(struct omap_iommu *obj,
315 				      struct iotlb_entry *e)
316 {
317 	struct cr_regs *cr;
318 
319 	if (!e)
320 		return NULL;
321 
322 	if (e->da & ~(get_cam_va_mask(e->pgsz))) {
323 		dev_err(obj->dev, "%s:\twrong alignment: %08x\n", __func__,
324 			e->da);
325 		return ERR_PTR(-EINVAL);
326 	}
327 
328 	cr = kmalloc(sizeof(*cr), GFP_KERNEL);
329 	if (!cr)
330 		return ERR_PTR(-ENOMEM);
331 
332 	cr->cam = (e->da & MMU_CAM_VATAG_MASK) | e->prsvd | e->pgsz | e->valid;
333 	cr->ram = e->pa | e->endian | e->elsz | e->mixed;
334 
335 	return cr;
336 }
337 
338 /**
339  * load_iotlb_entry - Set an iommu tlb entry
340  * @obj:	target iommu
341  * @e:		an iommu tlb entry info
342  **/
343 static int load_iotlb_entry(struct omap_iommu *obj, struct iotlb_entry *e)
344 {
345 	int err = 0;
346 	struct iotlb_lock l;
347 	struct cr_regs *cr;
348 
349 	if (!obj || !obj->nr_tlb_entries || !e)
350 		return -EINVAL;
351 
352 	pm_runtime_get_sync(obj->dev);
353 
354 	iotlb_lock_get(obj, &l);
355 	if (l.base == obj->nr_tlb_entries) {
356 		dev_warn(obj->dev, "%s: preserve entries full\n", __func__);
357 		err = -EBUSY;
358 		goto out;
359 	}
360 	if (!e->prsvd) {
361 		int i;
362 		struct cr_regs tmp;
363 
364 		for_each_iotlb_cr(obj, obj->nr_tlb_entries, i, tmp)
365 			if (!iotlb_cr_valid(&tmp))
366 				break;
367 
368 		if (i == obj->nr_tlb_entries) {
369 			dev_dbg(obj->dev, "%s: full: no entry\n", __func__);
370 			err = -EBUSY;
371 			goto out;
372 		}
373 
374 		iotlb_lock_get(obj, &l);
375 	} else {
376 		l.vict = l.base;
377 		iotlb_lock_set(obj, &l);
378 	}
379 
380 	cr = iotlb_alloc_cr(obj, e);
381 	if (IS_ERR(cr)) {
382 		pm_runtime_put_sync(obj->dev);
383 		return PTR_ERR(cr);
384 	}
385 
386 	iotlb_load_cr(obj, cr);
387 	kfree(cr);
388 
389 	if (e->prsvd)
390 		l.base++;
391 	/* increment victim for next tlb load */
392 	if (++l.vict == obj->nr_tlb_entries)
393 		l.vict = l.base;
394 	iotlb_lock_set(obj, &l);
395 out:
396 	pm_runtime_put_sync(obj->dev);
397 	return err;
398 }
399 
400 #else /* !PREFETCH_IOTLB */
401 
402 static int load_iotlb_entry(struct omap_iommu *obj, struct iotlb_entry *e)
403 {
404 	return 0;
405 }
406 
407 #endif /* !PREFETCH_IOTLB */
408 
409 static int prefetch_iotlb_entry(struct omap_iommu *obj, struct iotlb_entry *e)
410 {
411 	return load_iotlb_entry(obj, e);
412 }
413 
414 /**
415  * flush_iotlb_page - Clear an iommu tlb entry
416  * @obj:	target iommu
417  * @da:		iommu device virtual address
418  *
419  * Clear an iommu tlb entry which includes 'da' address.
420  **/
421 static void flush_iotlb_page(struct omap_iommu *obj, u32 da)
422 {
423 	int i;
424 	struct cr_regs cr;
425 
426 	pm_runtime_get_sync(obj->dev);
427 
428 	for_each_iotlb_cr(obj, obj->nr_tlb_entries, i, cr) {
429 		u32 start;
430 		size_t bytes;
431 
432 		if (!iotlb_cr_valid(&cr))
433 			continue;
434 
435 		start = iotlb_cr_to_virt(&cr);
436 		bytes = iopgsz_to_bytes(cr.cam & 3);
437 
438 		if ((start <= da) && (da < start + bytes)) {
439 			dev_dbg(obj->dev, "%s: %08x<=%08x(%x)\n",
440 				__func__, start, da, bytes);
441 			iotlb_load_cr(obj, &cr);
442 			iommu_write_reg(obj, 1, MMU_FLUSH_ENTRY);
443 			break;
444 		}
445 	}
446 	pm_runtime_put_sync(obj->dev);
447 
448 	if (i == obj->nr_tlb_entries)
449 		dev_dbg(obj->dev, "%s: no page for %08x\n", __func__, da);
450 }
451 
452 /**
453  * flush_iotlb_all - Clear all iommu tlb entries
454  * @obj:	target iommu
455  **/
456 static void flush_iotlb_all(struct omap_iommu *obj)
457 {
458 	struct iotlb_lock l;
459 
460 	pm_runtime_get_sync(obj->dev);
461 
462 	l.base = 0;
463 	l.vict = 0;
464 	iotlb_lock_set(obj, &l);
465 
466 	iommu_write_reg(obj, 1, MMU_GFLUSH);
467 
468 	pm_runtime_put_sync(obj->dev);
469 }
470 
471 /*
472  *	H/W pagetable operations
473  */
474 static void flush_iopte_range(struct device *dev, dma_addr_t dma,
475 			      unsigned long offset, int num_entries)
476 {
477 	size_t size = num_entries * sizeof(u32);
478 
479 	dma_sync_single_range_for_device(dev, dma, offset, size, DMA_TO_DEVICE);
480 }
481 
482 static void iopte_free(struct omap_iommu *obj, u32 *iopte, bool dma_valid)
483 {
484 	dma_addr_t pt_dma;
485 
486 	/* Note: freed iopte's must be clean ready for re-use */
487 	if (iopte) {
488 		if (dma_valid) {
489 			pt_dma = virt_to_phys(iopte);
490 			dma_unmap_single(obj->dev, pt_dma, IOPTE_TABLE_SIZE,
491 					 DMA_TO_DEVICE);
492 		}
493 
494 		kmem_cache_free(iopte_cachep, iopte);
495 	}
496 }
497 
498 static u32 *iopte_alloc(struct omap_iommu *obj, u32 *iopgd,
499 			dma_addr_t *pt_dma, u32 da)
500 {
501 	u32 *iopte;
502 	unsigned long offset = iopgd_index(da) * sizeof(da);
503 
504 	/* a table has already existed */
505 	if (*iopgd)
506 		goto pte_ready;
507 
508 	/*
509 	 * do the allocation outside the page table lock
510 	 */
511 	spin_unlock(&obj->page_table_lock);
512 	iopte = kmem_cache_zalloc(iopte_cachep, GFP_KERNEL);
513 	spin_lock(&obj->page_table_lock);
514 
515 	if (!*iopgd) {
516 		if (!iopte)
517 			return ERR_PTR(-ENOMEM);
518 
519 		*pt_dma = dma_map_single(obj->dev, iopte, IOPTE_TABLE_SIZE,
520 					 DMA_TO_DEVICE);
521 		if (dma_mapping_error(obj->dev, *pt_dma)) {
522 			dev_err(obj->dev, "DMA map error for L2 table\n");
523 			iopte_free(obj, iopte, false);
524 			return ERR_PTR(-ENOMEM);
525 		}
526 
527 		/*
528 		 * we rely on dma address and the physical address to be
529 		 * the same for mapping the L2 table
530 		 */
531 		if (WARN_ON(*pt_dma != virt_to_phys(iopte))) {
532 			dev_err(obj->dev, "DMA translation error for L2 table\n");
533 			dma_unmap_single(obj->dev, *pt_dma, IOPTE_TABLE_SIZE,
534 					 DMA_TO_DEVICE);
535 			iopte_free(obj, iopte, false);
536 			return ERR_PTR(-ENOMEM);
537 		}
538 
539 		*iopgd = virt_to_phys(iopte) | IOPGD_TABLE;
540 
541 		flush_iopte_range(obj->dev, obj->pd_dma, offset, 1);
542 		dev_vdbg(obj->dev, "%s: a new pte:%p\n", __func__, iopte);
543 	} else {
544 		/* We raced, free the reduniovant table */
545 		iopte_free(obj, iopte, false);
546 	}
547 
548 pte_ready:
549 	iopte = iopte_offset(iopgd, da);
550 	*pt_dma = iopgd_page_paddr(iopgd);
551 	dev_vdbg(obj->dev,
552 		 "%s: da:%08x pgd:%p *pgd:%08x pte:%p *pte:%08x\n",
553 		 __func__, da, iopgd, *iopgd, iopte, *iopte);
554 
555 	return iopte;
556 }
557 
558 static int iopgd_alloc_section(struct omap_iommu *obj, u32 da, u32 pa, u32 prot)
559 {
560 	u32 *iopgd = iopgd_offset(obj, da);
561 	unsigned long offset = iopgd_index(da) * sizeof(da);
562 
563 	if ((da | pa) & ~IOSECTION_MASK) {
564 		dev_err(obj->dev, "%s: %08x:%08x should aligned on %08lx\n",
565 			__func__, da, pa, IOSECTION_SIZE);
566 		return -EINVAL;
567 	}
568 
569 	*iopgd = (pa & IOSECTION_MASK) | prot | IOPGD_SECTION;
570 	flush_iopte_range(obj->dev, obj->pd_dma, offset, 1);
571 	return 0;
572 }
573 
574 static int iopgd_alloc_super(struct omap_iommu *obj, u32 da, u32 pa, u32 prot)
575 {
576 	u32 *iopgd = iopgd_offset(obj, da);
577 	unsigned long offset = iopgd_index(da) * sizeof(da);
578 	int i;
579 
580 	if ((da | pa) & ~IOSUPER_MASK) {
581 		dev_err(obj->dev, "%s: %08x:%08x should aligned on %08lx\n",
582 			__func__, da, pa, IOSUPER_SIZE);
583 		return -EINVAL;
584 	}
585 
586 	for (i = 0; i < 16; i++)
587 		*(iopgd + i) = (pa & IOSUPER_MASK) | prot | IOPGD_SUPER;
588 	flush_iopte_range(obj->dev, obj->pd_dma, offset, 16);
589 	return 0;
590 }
591 
592 static int iopte_alloc_page(struct omap_iommu *obj, u32 da, u32 pa, u32 prot)
593 {
594 	u32 *iopgd = iopgd_offset(obj, da);
595 	dma_addr_t pt_dma;
596 	u32 *iopte = iopte_alloc(obj, iopgd, &pt_dma, da);
597 	unsigned long offset = iopte_index(da) * sizeof(da);
598 
599 	if (IS_ERR(iopte))
600 		return PTR_ERR(iopte);
601 
602 	*iopte = (pa & IOPAGE_MASK) | prot | IOPTE_SMALL;
603 	flush_iopte_range(obj->dev, pt_dma, offset, 1);
604 
605 	dev_vdbg(obj->dev, "%s: da:%08x pa:%08x pte:%p *pte:%08x\n",
606 		 __func__, da, pa, iopte, *iopte);
607 
608 	return 0;
609 }
610 
611 static int iopte_alloc_large(struct omap_iommu *obj, u32 da, u32 pa, u32 prot)
612 {
613 	u32 *iopgd = iopgd_offset(obj, da);
614 	dma_addr_t pt_dma;
615 	u32 *iopte = iopte_alloc(obj, iopgd, &pt_dma, da);
616 	unsigned long offset = iopte_index(da) * sizeof(da);
617 	int i;
618 
619 	if ((da | pa) & ~IOLARGE_MASK) {
620 		dev_err(obj->dev, "%s: %08x:%08x should aligned on %08lx\n",
621 			__func__, da, pa, IOLARGE_SIZE);
622 		return -EINVAL;
623 	}
624 
625 	if (IS_ERR(iopte))
626 		return PTR_ERR(iopte);
627 
628 	for (i = 0; i < 16; i++)
629 		*(iopte + i) = (pa & IOLARGE_MASK) | prot | IOPTE_LARGE;
630 	flush_iopte_range(obj->dev, pt_dma, offset, 16);
631 	return 0;
632 }
633 
634 static int
635 iopgtable_store_entry_core(struct omap_iommu *obj, struct iotlb_entry *e)
636 {
637 	int (*fn)(struct omap_iommu *, u32, u32, u32);
638 	u32 prot;
639 	int err;
640 
641 	if (!obj || !e)
642 		return -EINVAL;
643 
644 	switch (e->pgsz) {
645 	case MMU_CAM_PGSZ_16M:
646 		fn = iopgd_alloc_super;
647 		break;
648 	case MMU_CAM_PGSZ_1M:
649 		fn = iopgd_alloc_section;
650 		break;
651 	case MMU_CAM_PGSZ_64K:
652 		fn = iopte_alloc_large;
653 		break;
654 	case MMU_CAM_PGSZ_4K:
655 		fn = iopte_alloc_page;
656 		break;
657 	default:
658 		fn = NULL;
659 		break;
660 	}
661 
662 	if (WARN_ON(!fn))
663 		return -EINVAL;
664 
665 	prot = get_iopte_attr(e);
666 
667 	spin_lock(&obj->page_table_lock);
668 	err = fn(obj, e->da, e->pa, prot);
669 	spin_unlock(&obj->page_table_lock);
670 
671 	return err;
672 }
673 
674 /**
675  * omap_iopgtable_store_entry - Make an iommu pte entry
676  * @obj:	target iommu
677  * @e:		an iommu tlb entry info
678  **/
679 static int
680 omap_iopgtable_store_entry(struct omap_iommu *obj, struct iotlb_entry *e)
681 {
682 	int err;
683 
684 	flush_iotlb_page(obj, e->da);
685 	err = iopgtable_store_entry_core(obj, e);
686 	if (!err)
687 		prefetch_iotlb_entry(obj, e);
688 	return err;
689 }
690 
691 /**
692  * iopgtable_lookup_entry - Lookup an iommu pte entry
693  * @obj:	target iommu
694  * @da:		iommu device virtual address
695  * @ppgd:	iommu pgd entry pointer to be returned
696  * @ppte:	iommu pte entry pointer to be returned
697  **/
698 static void
699 iopgtable_lookup_entry(struct omap_iommu *obj, u32 da, u32 **ppgd, u32 **ppte)
700 {
701 	u32 *iopgd, *iopte = NULL;
702 
703 	iopgd = iopgd_offset(obj, da);
704 	if (!*iopgd)
705 		goto out;
706 
707 	if (iopgd_is_table(*iopgd))
708 		iopte = iopte_offset(iopgd, da);
709 out:
710 	*ppgd = iopgd;
711 	*ppte = iopte;
712 }
713 
714 static size_t iopgtable_clear_entry_core(struct omap_iommu *obj, u32 da)
715 {
716 	size_t bytes;
717 	u32 *iopgd = iopgd_offset(obj, da);
718 	int nent = 1;
719 	dma_addr_t pt_dma;
720 	unsigned long pd_offset = iopgd_index(da) * sizeof(da);
721 	unsigned long pt_offset = iopte_index(da) * sizeof(da);
722 
723 	if (!*iopgd)
724 		return 0;
725 
726 	if (iopgd_is_table(*iopgd)) {
727 		int i;
728 		u32 *iopte = iopte_offset(iopgd, da);
729 
730 		bytes = IOPTE_SIZE;
731 		if (*iopte & IOPTE_LARGE) {
732 			nent *= 16;
733 			/* rewind to the 1st entry */
734 			iopte = iopte_offset(iopgd, (da & IOLARGE_MASK));
735 		}
736 		bytes *= nent;
737 		memset(iopte, 0, nent * sizeof(*iopte));
738 		pt_dma = iopgd_page_paddr(iopgd);
739 		flush_iopte_range(obj->dev, pt_dma, pt_offset, nent);
740 
741 		/*
742 		 * do table walk to check if this table is necessary or not
743 		 */
744 		iopte = iopte_offset(iopgd, 0);
745 		for (i = 0; i < PTRS_PER_IOPTE; i++)
746 			if (iopte[i])
747 				goto out;
748 
749 		iopte_free(obj, iopte, true);
750 		nent = 1; /* for the next L1 entry */
751 	} else {
752 		bytes = IOPGD_SIZE;
753 		if ((*iopgd & IOPGD_SUPER) == IOPGD_SUPER) {
754 			nent *= 16;
755 			/* rewind to the 1st entry */
756 			iopgd = iopgd_offset(obj, (da & IOSUPER_MASK));
757 		}
758 		bytes *= nent;
759 	}
760 	memset(iopgd, 0, nent * sizeof(*iopgd));
761 	flush_iopte_range(obj->dev, obj->pd_dma, pd_offset, nent);
762 out:
763 	return bytes;
764 }
765 
766 /**
767  * iopgtable_clear_entry - Remove an iommu pte entry
768  * @obj:	target iommu
769  * @da:		iommu device virtual address
770  **/
771 static size_t iopgtable_clear_entry(struct omap_iommu *obj, u32 da)
772 {
773 	size_t bytes;
774 
775 	spin_lock(&obj->page_table_lock);
776 
777 	bytes = iopgtable_clear_entry_core(obj, da);
778 	flush_iotlb_page(obj, da);
779 
780 	spin_unlock(&obj->page_table_lock);
781 
782 	return bytes;
783 }
784 
785 static void iopgtable_clear_entry_all(struct omap_iommu *obj)
786 {
787 	unsigned long offset;
788 	int i;
789 
790 	spin_lock(&obj->page_table_lock);
791 
792 	for (i = 0; i < PTRS_PER_IOPGD; i++) {
793 		u32 da;
794 		u32 *iopgd;
795 
796 		da = i << IOPGD_SHIFT;
797 		iopgd = iopgd_offset(obj, da);
798 		offset = iopgd_index(da) * sizeof(da);
799 
800 		if (!*iopgd)
801 			continue;
802 
803 		if (iopgd_is_table(*iopgd))
804 			iopte_free(obj, iopte_offset(iopgd, 0), true);
805 
806 		*iopgd = 0;
807 		flush_iopte_range(obj->dev, obj->pd_dma, offset, 1);
808 	}
809 
810 	flush_iotlb_all(obj);
811 
812 	spin_unlock(&obj->page_table_lock);
813 }
814 
815 /*
816  *	Device IOMMU generic operations
817  */
818 static irqreturn_t iommu_fault_handler(int irq, void *data)
819 {
820 	u32 da, errs;
821 	u32 *iopgd, *iopte;
822 	struct omap_iommu *obj = data;
823 	struct iommu_domain *domain = obj->domain;
824 	struct omap_iommu_domain *omap_domain = to_omap_domain(domain);
825 
826 	if (!omap_domain->dev)
827 		return IRQ_NONE;
828 
829 	errs = iommu_report_fault(obj, &da);
830 	if (errs == 0)
831 		return IRQ_HANDLED;
832 
833 	/* Fault callback or TLB/PTE Dynamic loading */
834 	if (!report_iommu_fault(domain, obj->dev, da, 0))
835 		return IRQ_HANDLED;
836 
837 	iommu_write_reg(obj, 0, MMU_IRQENABLE);
838 
839 	iopgd = iopgd_offset(obj, da);
840 
841 	if (!iopgd_is_table(*iopgd)) {
842 		dev_err(obj->dev, "%s: errs:0x%08x da:0x%08x pgd:0x%p *pgd:px%08x\n",
843 			obj->name, errs, da, iopgd, *iopgd);
844 		return IRQ_NONE;
845 	}
846 
847 	iopte = iopte_offset(iopgd, da);
848 
849 	dev_err(obj->dev, "%s: errs:0x%08x da:0x%08x pgd:0x%p *pgd:0x%08x pte:0x%p *pte:0x%08x\n",
850 		obj->name, errs, da, iopgd, *iopgd, iopte, *iopte);
851 
852 	return IRQ_NONE;
853 }
854 
855 /**
856  * omap_iommu_attach() - attach iommu device to an iommu domain
857  * @obj:	target omap iommu device
858  * @iopgd:	page table
859  **/
860 static int omap_iommu_attach(struct omap_iommu *obj, u32 *iopgd)
861 {
862 	int err;
863 
864 	spin_lock(&obj->iommu_lock);
865 
866 	obj->pd_dma = dma_map_single(obj->dev, iopgd, IOPGD_TABLE_SIZE,
867 				     DMA_TO_DEVICE);
868 	if (dma_mapping_error(obj->dev, obj->pd_dma)) {
869 		dev_err(obj->dev, "DMA map error for L1 table\n");
870 		err = -ENOMEM;
871 		goto out_err;
872 	}
873 
874 	obj->iopgd = iopgd;
875 	err = iommu_enable(obj);
876 	if (err)
877 		goto out_err;
878 	flush_iotlb_all(obj);
879 
880 	spin_unlock(&obj->iommu_lock);
881 
882 	dev_dbg(obj->dev, "%s: %s\n", __func__, obj->name);
883 
884 	return 0;
885 
886 out_err:
887 	spin_unlock(&obj->iommu_lock);
888 
889 	return err;
890 }
891 
892 /**
893  * omap_iommu_detach - release iommu device
894  * @obj:	target iommu
895  **/
896 static void omap_iommu_detach(struct omap_iommu *obj)
897 {
898 	if (!obj || IS_ERR(obj))
899 		return;
900 
901 	spin_lock(&obj->iommu_lock);
902 
903 	dma_unmap_single(obj->dev, obj->pd_dma, IOPGD_TABLE_SIZE,
904 			 DMA_TO_DEVICE);
905 	iommu_disable(obj);
906 	obj->pd_dma = 0;
907 	obj->iopgd = NULL;
908 
909 	spin_unlock(&obj->iommu_lock);
910 
911 	dev_dbg(obj->dev, "%s: %s\n", __func__, obj->name);
912 }
913 
914 static bool omap_iommu_can_register(struct platform_device *pdev)
915 {
916 	struct device_node *np = pdev->dev.of_node;
917 
918 	if (!of_device_is_compatible(np, "ti,dra7-dsp-iommu"))
919 		return true;
920 
921 	/*
922 	 * restrict IOMMU core registration only for processor-port MDMA MMUs
923 	 * on DRA7 DSPs
924 	 */
925 	if ((!strcmp(dev_name(&pdev->dev), "40d01000.mmu")) ||
926 	    (!strcmp(dev_name(&pdev->dev), "41501000.mmu")))
927 		return true;
928 
929 	return false;
930 }
931 
932 static int omap_iommu_dra7_get_dsp_system_cfg(struct platform_device *pdev,
933 					      struct omap_iommu *obj)
934 {
935 	struct device_node *np = pdev->dev.of_node;
936 	int ret;
937 
938 	if (!of_device_is_compatible(np, "ti,dra7-dsp-iommu"))
939 		return 0;
940 
941 	if (!of_property_read_bool(np, "ti,syscon-mmuconfig")) {
942 		dev_err(&pdev->dev, "ti,syscon-mmuconfig property is missing\n");
943 		return -EINVAL;
944 	}
945 
946 	obj->syscfg =
947 		syscon_regmap_lookup_by_phandle(np, "ti,syscon-mmuconfig");
948 	if (IS_ERR(obj->syscfg)) {
949 		/* can fail with -EPROBE_DEFER */
950 		ret = PTR_ERR(obj->syscfg);
951 		return ret;
952 	}
953 
954 	if (of_property_read_u32_index(np, "ti,syscon-mmuconfig", 1,
955 				       &obj->id)) {
956 		dev_err(&pdev->dev, "couldn't get the IOMMU instance id within subsystem\n");
957 		return -EINVAL;
958 	}
959 
960 	if (obj->id != 0 && obj->id != 1) {
961 		dev_err(&pdev->dev, "invalid IOMMU instance id\n");
962 		return -EINVAL;
963 	}
964 
965 	return 0;
966 }
967 
968 /*
969  *	OMAP Device MMU(IOMMU) detection
970  */
971 static int omap_iommu_probe(struct platform_device *pdev)
972 {
973 	int err = -ENODEV;
974 	int irq;
975 	struct omap_iommu *obj;
976 	struct resource *res;
977 	struct device_node *of = pdev->dev.of_node;
978 
979 	if (!of) {
980 		pr_err("%s: only DT-based devices are supported\n", __func__);
981 		return -ENODEV;
982 	}
983 
984 	obj = devm_kzalloc(&pdev->dev, sizeof(*obj) + MMU_REG_SIZE, GFP_KERNEL);
985 	if (!obj)
986 		return -ENOMEM;
987 
988 	obj->name = dev_name(&pdev->dev);
989 	obj->nr_tlb_entries = 32;
990 	err = of_property_read_u32(of, "ti,#tlb-entries", &obj->nr_tlb_entries);
991 	if (err && err != -EINVAL)
992 		return err;
993 	if (obj->nr_tlb_entries != 32 && obj->nr_tlb_entries != 8)
994 		return -EINVAL;
995 	if (of_find_property(of, "ti,iommu-bus-err-back", NULL))
996 		obj->has_bus_err_back = MMU_GP_REG_BUS_ERR_BACK_EN;
997 
998 	obj->dev = &pdev->dev;
999 	obj->ctx = (void *)obj + sizeof(*obj);
1000 
1001 	spin_lock_init(&obj->iommu_lock);
1002 	spin_lock_init(&obj->page_table_lock);
1003 
1004 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1005 	obj->regbase = devm_ioremap_resource(obj->dev, res);
1006 	if (IS_ERR(obj->regbase))
1007 		return PTR_ERR(obj->regbase);
1008 
1009 	err = omap_iommu_dra7_get_dsp_system_cfg(pdev, obj);
1010 	if (err)
1011 		return err;
1012 
1013 	irq = platform_get_irq(pdev, 0);
1014 	if (irq < 0)
1015 		return -ENODEV;
1016 
1017 	err = devm_request_irq(obj->dev, irq, iommu_fault_handler, IRQF_SHARED,
1018 			       dev_name(obj->dev), obj);
1019 	if (err < 0)
1020 		return err;
1021 	platform_set_drvdata(pdev, obj);
1022 
1023 	if (omap_iommu_can_register(pdev)) {
1024 		obj->group = iommu_group_alloc();
1025 		if (IS_ERR(obj->group))
1026 			return PTR_ERR(obj->group);
1027 
1028 		err = iommu_device_sysfs_add(&obj->iommu, obj->dev, NULL,
1029 					     obj->name);
1030 		if (err)
1031 			goto out_group;
1032 
1033 		iommu_device_set_ops(&obj->iommu, &omap_iommu_ops);
1034 
1035 		err = iommu_device_register(&obj->iommu);
1036 		if (err)
1037 			goto out_sysfs;
1038 	}
1039 
1040 	pm_runtime_irq_safe(obj->dev);
1041 	pm_runtime_enable(obj->dev);
1042 
1043 	omap_iommu_debugfs_add(obj);
1044 
1045 	dev_info(&pdev->dev, "%s registered\n", obj->name);
1046 
1047 	return 0;
1048 
1049 out_sysfs:
1050 	iommu_device_sysfs_remove(&obj->iommu);
1051 out_group:
1052 	iommu_group_put(obj->group);
1053 	return err;
1054 }
1055 
1056 static int omap_iommu_remove(struct platform_device *pdev)
1057 {
1058 	struct omap_iommu *obj = platform_get_drvdata(pdev);
1059 
1060 	if (obj->group) {
1061 		iommu_group_put(obj->group);
1062 		obj->group = NULL;
1063 
1064 		iommu_device_sysfs_remove(&obj->iommu);
1065 		iommu_device_unregister(&obj->iommu);
1066 	}
1067 
1068 	omap_iommu_debugfs_remove(obj);
1069 
1070 	pm_runtime_disable(obj->dev);
1071 
1072 	dev_info(&pdev->dev, "%s removed\n", obj->name);
1073 	return 0;
1074 }
1075 
1076 static const struct of_device_id omap_iommu_of_match[] = {
1077 	{ .compatible = "ti,omap2-iommu" },
1078 	{ .compatible = "ti,omap4-iommu" },
1079 	{ .compatible = "ti,dra7-iommu"	},
1080 	{ .compatible = "ti,dra7-dsp-iommu" },
1081 	{},
1082 };
1083 
1084 static struct platform_driver omap_iommu_driver = {
1085 	.probe	= omap_iommu_probe,
1086 	.remove	= omap_iommu_remove,
1087 	.driver	= {
1088 		.name	= "omap-iommu",
1089 		.of_match_table = of_match_ptr(omap_iommu_of_match),
1090 	},
1091 };
1092 
1093 static u32 iotlb_init_entry(struct iotlb_entry *e, u32 da, u32 pa, int pgsz)
1094 {
1095 	memset(e, 0, sizeof(*e));
1096 
1097 	e->da		= da;
1098 	e->pa		= pa;
1099 	e->valid	= MMU_CAM_V;
1100 	e->pgsz		= pgsz;
1101 	e->endian	= MMU_RAM_ENDIAN_LITTLE;
1102 	e->elsz		= MMU_RAM_ELSZ_8;
1103 	e->mixed	= 0;
1104 
1105 	return iopgsz_to_bytes(e->pgsz);
1106 }
1107 
1108 static int omap_iommu_map(struct iommu_domain *domain, unsigned long da,
1109 			  phys_addr_t pa, size_t bytes, int prot)
1110 {
1111 	struct omap_iommu_domain *omap_domain = to_omap_domain(domain);
1112 	struct device *dev = omap_domain->dev;
1113 	struct omap_iommu_device *iommu;
1114 	struct omap_iommu *oiommu;
1115 	struct iotlb_entry e;
1116 	int omap_pgsz;
1117 	u32 ret = -EINVAL;
1118 	int i;
1119 
1120 	omap_pgsz = bytes_to_iopgsz(bytes);
1121 	if (omap_pgsz < 0) {
1122 		dev_err(dev, "invalid size to map: %d\n", bytes);
1123 		return -EINVAL;
1124 	}
1125 
1126 	dev_dbg(dev, "mapping da 0x%lx to pa %pa size 0x%x\n", da, &pa, bytes);
1127 
1128 	iotlb_init_entry(&e, da, pa, omap_pgsz);
1129 
1130 	iommu = omap_domain->iommus;
1131 	for (i = 0; i < omap_domain->num_iommus; i++, iommu++) {
1132 		oiommu = iommu->iommu_dev;
1133 		ret = omap_iopgtable_store_entry(oiommu, &e);
1134 		if (ret) {
1135 			dev_err(dev, "omap_iopgtable_store_entry failed: %d\n",
1136 				ret);
1137 			break;
1138 		}
1139 	}
1140 
1141 	if (ret) {
1142 		while (i--) {
1143 			iommu--;
1144 			oiommu = iommu->iommu_dev;
1145 			iopgtable_clear_entry(oiommu, da);
1146 		}
1147 	}
1148 
1149 	return ret;
1150 }
1151 
1152 static size_t omap_iommu_unmap(struct iommu_domain *domain, unsigned long da,
1153 			       size_t size)
1154 {
1155 	struct omap_iommu_domain *omap_domain = to_omap_domain(domain);
1156 	struct device *dev = omap_domain->dev;
1157 	struct omap_iommu_device *iommu;
1158 	struct omap_iommu *oiommu;
1159 	bool error = false;
1160 	size_t bytes = 0;
1161 	int i;
1162 
1163 	dev_dbg(dev, "unmapping da 0x%lx size %u\n", da, size);
1164 
1165 	iommu = omap_domain->iommus;
1166 	for (i = 0; i < omap_domain->num_iommus; i++, iommu++) {
1167 		oiommu = iommu->iommu_dev;
1168 		bytes = iopgtable_clear_entry(oiommu, da);
1169 		if (!bytes)
1170 			error = true;
1171 	}
1172 
1173 	/*
1174 	 * simplify return - we are only checking if any of the iommus
1175 	 * reported an error, but not if all of them are unmapping the
1176 	 * same number of entries. This should not occur due to the
1177 	 * mirror programming.
1178 	 */
1179 	return error ? 0 : bytes;
1180 }
1181 
1182 static int omap_iommu_count(struct device *dev)
1183 {
1184 	struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
1185 	int count = 0;
1186 
1187 	while (arch_data->iommu_dev) {
1188 		count++;
1189 		arch_data++;
1190 	}
1191 
1192 	return count;
1193 }
1194 
1195 /* caller should call cleanup if this function fails */
1196 static int omap_iommu_attach_init(struct device *dev,
1197 				  struct omap_iommu_domain *odomain)
1198 {
1199 	struct omap_iommu_device *iommu;
1200 	int i;
1201 
1202 	odomain->num_iommus = omap_iommu_count(dev);
1203 	if (!odomain->num_iommus)
1204 		return -EINVAL;
1205 
1206 	odomain->iommus = kcalloc(odomain->num_iommus, sizeof(*iommu),
1207 				  GFP_ATOMIC);
1208 	if (!odomain->iommus)
1209 		return -ENOMEM;
1210 
1211 	iommu = odomain->iommus;
1212 	for (i = 0; i < odomain->num_iommus; i++, iommu++) {
1213 		iommu->pgtable = kzalloc(IOPGD_TABLE_SIZE, GFP_ATOMIC);
1214 		if (!iommu->pgtable)
1215 			return -ENOMEM;
1216 
1217 		/*
1218 		 * should never fail, but please keep this around to ensure
1219 		 * we keep the hardware happy
1220 		 */
1221 		if (WARN_ON(!IS_ALIGNED((long)iommu->pgtable,
1222 					IOPGD_TABLE_SIZE)))
1223 			return -EINVAL;
1224 	}
1225 
1226 	return 0;
1227 }
1228 
1229 static void omap_iommu_detach_fini(struct omap_iommu_domain *odomain)
1230 {
1231 	int i;
1232 	struct omap_iommu_device *iommu = odomain->iommus;
1233 
1234 	for (i = 0; iommu && i < odomain->num_iommus; i++, iommu++)
1235 		kfree(iommu->pgtable);
1236 
1237 	kfree(odomain->iommus);
1238 	odomain->num_iommus = 0;
1239 	odomain->iommus = NULL;
1240 }
1241 
1242 static int
1243 omap_iommu_attach_dev(struct iommu_domain *domain, struct device *dev)
1244 {
1245 	struct omap_iommu_domain *omap_domain = to_omap_domain(domain);
1246 	struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
1247 	struct omap_iommu_device *iommu;
1248 	struct omap_iommu *oiommu;
1249 	int ret = 0;
1250 	int i;
1251 
1252 	if (!arch_data || !arch_data->iommu_dev) {
1253 		dev_err(dev, "device doesn't have an associated iommu\n");
1254 		return -EINVAL;
1255 	}
1256 
1257 	spin_lock(&omap_domain->lock);
1258 
1259 	/* only a single client device can be attached to a domain */
1260 	if (omap_domain->dev) {
1261 		dev_err(dev, "iommu domain is already attached\n");
1262 		ret = -EBUSY;
1263 		goto out;
1264 	}
1265 
1266 	ret = omap_iommu_attach_init(dev, omap_domain);
1267 	if (ret) {
1268 		dev_err(dev, "failed to allocate required iommu data %d\n",
1269 			ret);
1270 		goto init_fail;
1271 	}
1272 
1273 	iommu = omap_domain->iommus;
1274 	for (i = 0; i < omap_domain->num_iommus; i++, iommu++, arch_data++) {
1275 		/* configure and enable the omap iommu */
1276 		oiommu = arch_data->iommu_dev;
1277 		ret = omap_iommu_attach(oiommu, iommu->pgtable);
1278 		if (ret) {
1279 			dev_err(dev, "can't get omap iommu: %d\n", ret);
1280 			goto attach_fail;
1281 		}
1282 
1283 		oiommu->domain = domain;
1284 		iommu->iommu_dev = oiommu;
1285 	}
1286 
1287 	omap_domain->dev = dev;
1288 
1289 	goto out;
1290 
1291 attach_fail:
1292 	while (i--) {
1293 		iommu--;
1294 		arch_data--;
1295 		oiommu = iommu->iommu_dev;
1296 		omap_iommu_detach(oiommu);
1297 		iommu->iommu_dev = NULL;
1298 		oiommu->domain = NULL;
1299 	}
1300 init_fail:
1301 	omap_iommu_detach_fini(omap_domain);
1302 out:
1303 	spin_unlock(&omap_domain->lock);
1304 	return ret;
1305 }
1306 
1307 static void _omap_iommu_detach_dev(struct omap_iommu_domain *omap_domain,
1308 				   struct device *dev)
1309 {
1310 	struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
1311 	struct omap_iommu_device *iommu = omap_domain->iommus;
1312 	struct omap_iommu *oiommu;
1313 	int i;
1314 
1315 	if (!omap_domain->dev) {
1316 		dev_err(dev, "domain has no attached device\n");
1317 		return;
1318 	}
1319 
1320 	/* only a single device is supported per domain for now */
1321 	if (omap_domain->dev != dev) {
1322 		dev_err(dev, "invalid attached device\n");
1323 		return;
1324 	}
1325 
1326 	/*
1327 	 * cleanup in the reverse order of attachment - this addresses
1328 	 * any h/w dependencies between multiple instances, if any
1329 	 */
1330 	iommu += (omap_domain->num_iommus - 1);
1331 	arch_data += (omap_domain->num_iommus - 1);
1332 	for (i = 0; i < omap_domain->num_iommus; i++, iommu--, arch_data--) {
1333 		oiommu = iommu->iommu_dev;
1334 		iopgtable_clear_entry_all(oiommu);
1335 
1336 		omap_iommu_detach(oiommu);
1337 		iommu->iommu_dev = NULL;
1338 		oiommu->domain = NULL;
1339 	}
1340 
1341 	omap_iommu_detach_fini(omap_domain);
1342 
1343 	omap_domain->dev = NULL;
1344 }
1345 
1346 static void omap_iommu_detach_dev(struct iommu_domain *domain,
1347 				  struct device *dev)
1348 {
1349 	struct omap_iommu_domain *omap_domain = to_omap_domain(domain);
1350 
1351 	spin_lock(&omap_domain->lock);
1352 	_omap_iommu_detach_dev(omap_domain, dev);
1353 	spin_unlock(&omap_domain->lock);
1354 }
1355 
1356 static struct iommu_domain *omap_iommu_domain_alloc(unsigned type)
1357 {
1358 	struct omap_iommu_domain *omap_domain;
1359 
1360 	if (type != IOMMU_DOMAIN_UNMANAGED)
1361 		return NULL;
1362 
1363 	omap_domain = kzalloc(sizeof(*omap_domain), GFP_KERNEL);
1364 	if (!omap_domain)
1365 		return NULL;
1366 
1367 	spin_lock_init(&omap_domain->lock);
1368 
1369 	omap_domain->domain.geometry.aperture_start = 0;
1370 	omap_domain->domain.geometry.aperture_end   = (1ULL << 32) - 1;
1371 	omap_domain->domain.geometry.force_aperture = true;
1372 
1373 	return &omap_domain->domain;
1374 }
1375 
1376 static void omap_iommu_domain_free(struct iommu_domain *domain)
1377 {
1378 	struct omap_iommu_domain *omap_domain = to_omap_domain(domain);
1379 
1380 	/*
1381 	 * An iommu device is still attached
1382 	 * (currently, only one device can be attached) ?
1383 	 */
1384 	if (omap_domain->dev)
1385 		_omap_iommu_detach_dev(omap_domain, omap_domain->dev);
1386 
1387 	kfree(omap_domain);
1388 }
1389 
1390 static phys_addr_t omap_iommu_iova_to_phys(struct iommu_domain *domain,
1391 					   dma_addr_t da)
1392 {
1393 	struct omap_iommu_domain *omap_domain = to_omap_domain(domain);
1394 	struct omap_iommu_device *iommu = omap_domain->iommus;
1395 	struct omap_iommu *oiommu = iommu->iommu_dev;
1396 	struct device *dev = oiommu->dev;
1397 	u32 *pgd, *pte;
1398 	phys_addr_t ret = 0;
1399 
1400 	/*
1401 	 * all the iommus within the domain will have identical programming,
1402 	 * so perform the lookup using just the first iommu
1403 	 */
1404 	iopgtable_lookup_entry(oiommu, da, &pgd, &pte);
1405 
1406 	if (pte) {
1407 		if (iopte_is_small(*pte))
1408 			ret = omap_iommu_translate(*pte, da, IOPTE_MASK);
1409 		else if (iopte_is_large(*pte))
1410 			ret = omap_iommu_translate(*pte, da, IOLARGE_MASK);
1411 		else
1412 			dev_err(dev, "bogus pte 0x%x, da 0x%llx", *pte,
1413 				(unsigned long long)da);
1414 	} else {
1415 		if (iopgd_is_section(*pgd))
1416 			ret = omap_iommu_translate(*pgd, da, IOSECTION_MASK);
1417 		else if (iopgd_is_super(*pgd))
1418 			ret = omap_iommu_translate(*pgd, da, IOSUPER_MASK);
1419 		else
1420 			dev_err(dev, "bogus pgd 0x%x, da 0x%llx", *pgd,
1421 				(unsigned long long)da);
1422 	}
1423 
1424 	return ret;
1425 }
1426 
1427 static int omap_iommu_add_device(struct device *dev)
1428 {
1429 	struct omap_iommu_arch_data *arch_data, *tmp;
1430 	struct omap_iommu *oiommu;
1431 	struct iommu_group *group;
1432 	struct device_node *np;
1433 	struct platform_device *pdev;
1434 	int num_iommus, i;
1435 	int ret;
1436 
1437 	/*
1438 	 * Allocate the archdata iommu structure for DT-based devices.
1439 	 *
1440 	 * TODO: Simplify this when removing non-DT support completely from the
1441 	 * IOMMU users.
1442 	 */
1443 	if (!dev->of_node)
1444 		return 0;
1445 
1446 	/*
1447 	 * retrieve the count of IOMMU nodes using phandle size as element size
1448 	 * since #iommu-cells = 0 for OMAP
1449 	 */
1450 	num_iommus = of_property_count_elems_of_size(dev->of_node, "iommus",
1451 						     sizeof(phandle));
1452 	if (num_iommus < 0)
1453 		return 0;
1454 
1455 	arch_data = kcalloc(num_iommus + 1, sizeof(*arch_data), GFP_KERNEL);
1456 	if (!arch_data)
1457 		return -ENOMEM;
1458 
1459 	for (i = 0, tmp = arch_data; i < num_iommus; i++, tmp++) {
1460 		np = of_parse_phandle(dev->of_node, "iommus", i);
1461 		if (!np) {
1462 			kfree(arch_data);
1463 			return -EINVAL;
1464 		}
1465 
1466 		pdev = of_find_device_by_node(np);
1467 		if (WARN_ON(!pdev)) {
1468 			of_node_put(np);
1469 			kfree(arch_data);
1470 			return -EINVAL;
1471 		}
1472 
1473 		oiommu = platform_get_drvdata(pdev);
1474 		if (!oiommu) {
1475 			of_node_put(np);
1476 			kfree(arch_data);
1477 			return -EINVAL;
1478 		}
1479 
1480 		tmp->iommu_dev = oiommu;
1481 
1482 		of_node_put(np);
1483 	}
1484 
1485 	/*
1486 	 * use the first IOMMU alone for the sysfs device linking.
1487 	 * TODO: Evaluate if a single iommu_group needs to be
1488 	 * maintained for both IOMMUs
1489 	 */
1490 	oiommu = arch_data->iommu_dev;
1491 	ret = iommu_device_link(&oiommu->iommu, dev);
1492 	if (ret) {
1493 		kfree(arch_data);
1494 		return ret;
1495 	}
1496 
1497 	dev->archdata.iommu = arch_data;
1498 
1499 	/*
1500 	 * IOMMU group initialization calls into omap_iommu_device_group, which
1501 	 * needs a valid dev->archdata.iommu pointer
1502 	 */
1503 	group = iommu_group_get_for_dev(dev);
1504 	if (IS_ERR(group)) {
1505 		iommu_device_unlink(&oiommu->iommu, dev);
1506 		dev->archdata.iommu = NULL;
1507 		kfree(arch_data);
1508 		return PTR_ERR(group);
1509 	}
1510 	iommu_group_put(group);
1511 
1512 	return 0;
1513 }
1514 
1515 static void omap_iommu_remove_device(struct device *dev)
1516 {
1517 	struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
1518 
1519 	if (!dev->of_node || !arch_data)
1520 		return;
1521 
1522 	iommu_device_unlink(&arch_data->iommu_dev->iommu, dev);
1523 	iommu_group_remove_device(dev);
1524 
1525 	dev->archdata.iommu = NULL;
1526 	kfree(arch_data);
1527 
1528 }
1529 
1530 static struct iommu_group *omap_iommu_device_group(struct device *dev)
1531 {
1532 	struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
1533 	struct iommu_group *group = ERR_PTR(-EINVAL);
1534 
1535 	if (arch_data->iommu_dev)
1536 		group = iommu_group_ref_get(arch_data->iommu_dev->group);
1537 
1538 	return group;
1539 }
1540 
1541 static const struct iommu_ops omap_iommu_ops = {
1542 	.domain_alloc	= omap_iommu_domain_alloc,
1543 	.domain_free	= omap_iommu_domain_free,
1544 	.attach_dev	= omap_iommu_attach_dev,
1545 	.detach_dev	= omap_iommu_detach_dev,
1546 	.map		= omap_iommu_map,
1547 	.unmap		= omap_iommu_unmap,
1548 	.iova_to_phys	= omap_iommu_iova_to_phys,
1549 	.add_device	= omap_iommu_add_device,
1550 	.remove_device	= omap_iommu_remove_device,
1551 	.device_group	= omap_iommu_device_group,
1552 	.pgsize_bitmap	= OMAP_IOMMU_PGSIZES,
1553 };
1554 
1555 static int __init omap_iommu_init(void)
1556 {
1557 	struct kmem_cache *p;
1558 	const unsigned long flags = SLAB_HWCACHE_ALIGN;
1559 	size_t align = 1 << 10; /* L2 pagetable alignement */
1560 	struct device_node *np;
1561 	int ret;
1562 
1563 	np = of_find_matching_node(NULL, omap_iommu_of_match);
1564 	if (!np)
1565 		return 0;
1566 
1567 	of_node_put(np);
1568 
1569 	p = kmem_cache_create("iopte_cache", IOPTE_TABLE_SIZE, align, flags,
1570 			      NULL);
1571 	if (!p)
1572 		return -ENOMEM;
1573 	iopte_cachep = p;
1574 
1575 	omap_iommu_debugfs_init();
1576 
1577 	ret = platform_driver_register(&omap_iommu_driver);
1578 	if (ret) {
1579 		pr_err("%s: failed to register driver\n", __func__);
1580 		goto fail_driver;
1581 	}
1582 
1583 	ret = bus_set_iommu(&platform_bus_type, &omap_iommu_ops);
1584 	if (ret)
1585 		goto fail_bus;
1586 
1587 	return 0;
1588 
1589 fail_bus:
1590 	platform_driver_unregister(&omap_iommu_driver);
1591 fail_driver:
1592 	kmem_cache_destroy(iopte_cachep);
1593 	return ret;
1594 }
1595 subsys_initcall(omap_iommu_init);
1596 /* must be ready before omap3isp is probed */
1597