xref: /openbmc/linux/drivers/iommu/omap-iommu.c (revision ebd09753)
1 /*
2  * omap iommu: tlb and pagetable primitives
3  *
4  * Copyright (C) 2008-2010 Nokia Corporation
5  * Copyright (C) 2013-2017 Texas Instruments Incorporated - http://www.ti.com/
6  *
7  * Written by Hiroshi DOYU <Hiroshi.DOYU@nokia.com>,
8  *		Paul Mundt and Toshihiro Kobayashi
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License version 2 as
12  * published by the Free Software Foundation.
13  */
14 
15 #include <linux/dma-mapping.h>
16 #include <linux/err.h>
17 #include <linux/slab.h>
18 #include <linux/interrupt.h>
19 #include <linux/ioport.h>
20 #include <linux/platform_device.h>
21 #include <linux/iommu.h>
22 #include <linux/omap-iommu.h>
23 #include <linux/mutex.h>
24 #include <linux/spinlock.h>
25 #include <linux/io.h>
26 #include <linux/pm_runtime.h>
27 #include <linux/of.h>
28 #include <linux/of_iommu.h>
29 #include <linux/of_irq.h>
30 #include <linux/of_platform.h>
31 #include <linux/regmap.h>
32 #include <linux/mfd/syscon.h>
33 
34 #include <linux/platform_data/iommu-omap.h>
35 
36 #include "omap-iopgtable.h"
37 #include "omap-iommu.h"
38 
39 static const struct iommu_ops omap_iommu_ops;
40 
41 #define to_iommu(dev)							\
42 	((struct omap_iommu *)platform_get_drvdata(to_platform_device(dev)))
43 
44 /* bitmap of the page sizes currently supported */
45 #define OMAP_IOMMU_PGSIZES	(SZ_4K | SZ_64K | SZ_1M | SZ_16M)
46 
47 #define MMU_LOCK_BASE_SHIFT	10
48 #define MMU_LOCK_BASE_MASK	(0x1f << MMU_LOCK_BASE_SHIFT)
49 #define MMU_LOCK_BASE(x)	\
50 	((x & MMU_LOCK_BASE_MASK) >> MMU_LOCK_BASE_SHIFT)
51 
52 #define MMU_LOCK_VICT_SHIFT	4
53 #define MMU_LOCK_VICT_MASK	(0x1f << MMU_LOCK_VICT_SHIFT)
54 #define MMU_LOCK_VICT(x)	\
55 	((x & MMU_LOCK_VICT_MASK) >> MMU_LOCK_VICT_SHIFT)
56 
57 static struct platform_driver omap_iommu_driver;
58 static struct kmem_cache *iopte_cachep;
59 
60 /**
61  * to_omap_domain - Get struct omap_iommu_domain from generic iommu_domain
62  * @dom:	generic iommu domain handle
63  **/
64 static struct omap_iommu_domain *to_omap_domain(struct iommu_domain *dom)
65 {
66 	return container_of(dom, struct omap_iommu_domain, domain);
67 }
68 
69 /**
70  * omap_iommu_save_ctx - Save registers for pm off-mode support
71  * @dev:	client device
72  **/
73 void omap_iommu_save_ctx(struct device *dev)
74 {
75 	struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
76 	struct omap_iommu *obj;
77 	u32 *p;
78 	int i;
79 
80 	if (!arch_data)
81 		return;
82 
83 	while (arch_data->iommu_dev) {
84 		obj = arch_data->iommu_dev;
85 		p = obj->ctx;
86 		for (i = 0; i < (MMU_REG_SIZE / sizeof(u32)); i++) {
87 			p[i] = iommu_read_reg(obj, i * sizeof(u32));
88 			dev_dbg(obj->dev, "%s\t[%02d] %08x\n", __func__, i,
89 				p[i]);
90 		}
91 		arch_data++;
92 	}
93 }
94 EXPORT_SYMBOL_GPL(omap_iommu_save_ctx);
95 
96 /**
97  * omap_iommu_restore_ctx - Restore registers for pm off-mode support
98  * @dev:	client device
99  **/
100 void omap_iommu_restore_ctx(struct device *dev)
101 {
102 	struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
103 	struct omap_iommu *obj;
104 	u32 *p;
105 	int i;
106 
107 	if (!arch_data)
108 		return;
109 
110 	while (arch_data->iommu_dev) {
111 		obj = arch_data->iommu_dev;
112 		p = obj->ctx;
113 		for (i = 0; i < (MMU_REG_SIZE / sizeof(u32)); i++) {
114 			iommu_write_reg(obj, p[i], i * sizeof(u32));
115 			dev_dbg(obj->dev, "%s\t[%02d] %08x\n", __func__, i,
116 				p[i]);
117 		}
118 		arch_data++;
119 	}
120 }
121 EXPORT_SYMBOL_GPL(omap_iommu_restore_ctx);
122 
123 static void dra7_cfg_dspsys_mmu(struct omap_iommu *obj, bool enable)
124 {
125 	u32 val, mask;
126 
127 	if (!obj->syscfg)
128 		return;
129 
130 	mask = (1 << (obj->id * DSP_SYS_MMU_CONFIG_EN_SHIFT));
131 	val = enable ? mask : 0;
132 	regmap_update_bits(obj->syscfg, DSP_SYS_MMU_CONFIG, mask, val);
133 }
134 
135 static void __iommu_set_twl(struct omap_iommu *obj, bool on)
136 {
137 	u32 l = iommu_read_reg(obj, MMU_CNTL);
138 
139 	if (on)
140 		iommu_write_reg(obj, MMU_IRQ_TWL_MASK, MMU_IRQENABLE);
141 	else
142 		iommu_write_reg(obj, MMU_IRQ_TLB_MISS_MASK, MMU_IRQENABLE);
143 
144 	l &= ~MMU_CNTL_MASK;
145 	if (on)
146 		l |= (MMU_CNTL_MMU_EN | MMU_CNTL_TWL_EN);
147 	else
148 		l |= (MMU_CNTL_MMU_EN);
149 
150 	iommu_write_reg(obj, l, MMU_CNTL);
151 }
152 
153 static int omap2_iommu_enable(struct omap_iommu *obj)
154 {
155 	u32 l, pa;
156 
157 	if (!obj->iopgd || !IS_ALIGNED((u32)obj->iopgd,  SZ_16K))
158 		return -EINVAL;
159 
160 	pa = virt_to_phys(obj->iopgd);
161 	if (!IS_ALIGNED(pa, SZ_16K))
162 		return -EINVAL;
163 
164 	l = iommu_read_reg(obj, MMU_REVISION);
165 	dev_info(obj->dev, "%s: version %d.%d\n", obj->name,
166 		 (l >> 4) & 0xf, l & 0xf);
167 
168 	iommu_write_reg(obj, pa, MMU_TTB);
169 
170 	dra7_cfg_dspsys_mmu(obj, true);
171 
172 	if (obj->has_bus_err_back)
173 		iommu_write_reg(obj, MMU_GP_REG_BUS_ERR_BACK_EN, MMU_GP_REG);
174 
175 	__iommu_set_twl(obj, true);
176 
177 	return 0;
178 }
179 
180 static void omap2_iommu_disable(struct omap_iommu *obj)
181 {
182 	u32 l = iommu_read_reg(obj, MMU_CNTL);
183 
184 	l &= ~MMU_CNTL_MASK;
185 	iommu_write_reg(obj, l, MMU_CNTL);
186 	dra7_cfg_dspsys_mmu(obj, false);
187 
188 	dev_dbg(obj->dev, "%s is shutting down\n", obj->name);
189 }
190 
191 static int iommu_enable(struct omap_iommu *obj)
192 {
193 	int err;
194 	struct platform_device *pdev = to_platform_device(obj->dev);
195 	struct iommu_platform_data *pdata = dev_get_platdata(&pdev->dev);
196 
197 	if (pdata && pdata->deassert_reset) {
198 		err = pdata->deassert_reset(pdev, pdata->reset_name);
199 		if (err) {
200 			dev_err(obj->dev, "deassert_reset failed: %d\n", err);
201 			return err;
202 		}
203 	}
204 
205 	pm_runtime_get_sync(obj->dev);
206 
207 	err = omap2_iommu_enable(obj);
208 
209 	return err;
210 }
211 
212 static void iommu_disable(struct omap_iommu *obj)
213 {
214 	struct platform_device *pdev = to_platform_device(obj->dev);
215 	struct iommu_platform_data *pdata = dev_get_platdata(&pdev->dev);
216 
217 	omap2_iommu_disable(obj);
218 
219 	pm_runtime_put_sync(obj->dev);
220 
221 	if (pdata && pdata->assert_reset)
222 		pdata->assert_reset(pdev, pdata->reset_name);
223 }
224 
225 /*
226  *	TLB operations
227  */
228 static u32 iotlb_cr_to_virt(struct cr_regs *cr)
229 {
230 	u32 page_size = cr->cam & MMU_CAM_PGSZ_MASK;
231 	u32 mask = get_cam_va_mask(cr->cam & page_size);
232 
233 	return cr->cam & mask;
234 }
235 
236 static u32 get_iopte_attr(struct iotlb_entry *e)
237 {
238 	u32 attr;
239 
240 	attr = e->mixed << 5;
241 	attr |= e->endian;
242 	attr |= e->elsz >> 3;
243 	attr <<= (((e->pgsz == MMU_CAM_PGSZ_4K) ||
244 			(e->pgsz == MMU_CAM_PGSZ_64K)) ? 0 : 6);
245 	return attr;
246 }
247 
248 static u32 iommu_report_fault(struct omap_iommu *obj, u32 *da)
249 {
250 	u32 status, fault_addr;
251 
252 	status = iommu_read_reg(obj, MMU_IRQSTATUS);
253 	status &= MMU_IRQ_MASK;
254 	if (!status) {
255 		*da = 0;
256 		return 0;
257 	}
258 
259 	fault_addr = iommu_read_reg(obj, MMU_FAULT_AD);
260 	*da = fault_addr;
261 
262 	iommu_write_reg(obj, status, MMU_IRQSTATUS);
263 
264 	return status;
265 }
266 
267 void iotlb_lock_get(struct omap_iommu *obj, struct iotlb_lock *l)
268 {
269 	u32 val;
270 
271 	val = iommu_read_reg(obj, MMU_LOCK);
272 
273 	l->base = MMU_LOCK_BASE(val);
274 	l->vict = MMU_LOCK_VICT(val);
275 }
276 
277 void iotlb_lock_set(struct omap_iommu *obj, struct iotlb_lock *l)
278 {
279 	u32 val;
280 
281 	val = (l->base << MMU_LOCK_BASE_SHIFT);
282 	val |= (l->vict << MMU_LOCK_VICT_SHIFT);
283 
284 	iommu_write_reg(obj, val, MMU_LOCK);
285 }
286 
287 static void iotlb_read_cr(struct omap_iommu *obj, struct cr_regs *cr)
288 {
289 	cr->cam = iommu_read_reg(obj, MMU_READ_CAM);
290 	cr->ram = iommu_read_reg(obj, MMU_READ_RAM);
291 }
292 
293 static void iotlb_load_cr(struct omap_iommu *obj, struct cr_regs *cr)
294 {
295 	iommu_write_reg(obj, cr->cam | MMU_CAM_V, MMU_CAM);
296 	iommu_write_reg(obj, cr->ram, MMU_RAM);
297 
298 	iommu_write_reg(obj, 1, MMU_FLUSH_ENTRY);
299 	iommu_write_reg(obj, 1, MMU_LD_TLB);
300 }
301 
302 /* only used in iotlb iteration for-loop */
303 struct cr_regs __iotlb_read_cr(struct omap_iommu *obj, int n)
304 {
305 	struct cr_regs cr;
306 	struct iotlb_lock l;
307 
308 	iotlb_lock_get(obj, &l);
309 	l.vict = n;
310 	iotlb_lock_set(obj, &l);
311 	iotlb_read_cr(obj, &cr);
312 
313 	return cr;
314 }
315 
316 #ifdef PREFETCH_IOTLB
317 static struct cr_regs *iotlb_alloc_cr(struct omap_iommu *obj,
318 				      struct iotlb_entry *e)
319 {
320 	struct cr_regs *cr;
321 
322 	if (!e)
323 		return NULL;
324 
325 	if (e->da & ~(get_cam_va_mask(e->pgsz))) {
326 		dev_err(obj->dev, "%s:\twrong alignment: %08x\n", __func__,
327 			e->da);
328 		return ERR_PTR(-EINVAL);
329 	}
330 
331 	cr = kmalloc(sizeof(*cr), GFP_KERNEL);
332 	if (!cr)
333 		return ERR_PTR(-ENOMEM);
334 
335 	cr->cam = (e->da & MMU_CAM_VATAG_MASK) | e->prsvd | e->pgsz | e->valid;
336 	cr->ram = e->pa | e->endian | e->elsz | e->mixed;
337 
338 	return cr;
339 }
340 
341 /**
342  * load_iotlb_entry - Set an iommu tlb entry
343  * @obj:	target iommu
344  * @e:		an iommu tlb entry info
345  **/
346 static int load_iotlb_entry(struct omap_iommu *obj, struct iotlb_entry *e)
347 {
348 	int err = 0;
349 	struct iotlb_lock l;
350 	struct cr_regs *cr;
351 
352 	if (!obj || !obj->nr_tlb_entries || !e)
353 		return -EINVAL;
354 
355 	pm_runtime_get_sync(obj->dev);
356 
357 	iotlb_lock_get(obj, &l);
358 	if (l.base == obj->nr_tlb_entries) {
359 		dev_warn(obj->dev, "%s: preserve entries full\n", __func__);
360 		err = -EBUSY;
361 		goto out;
362 	}
363 	if (!e->prsvd) {
364 		int i;
365 		struct cr_regs tmp;
366 
367 		for_each_iotlb_cr(obj, obj->nr_tlb_entries, i, tmp)
368 			if (!iotlb_cr_valid(&tmp))
369 				break;
370 
371 		if (i == obj->nr_tlb_entries) {
372 			dev_dbg(obj->dev, "%s: full: no entry\n", __func__);
373 			err = -EBUSY;
374 			goto out;
375 		}
376 
377 		iotlb_lock_get(obj, &l);
378 	} else {
379 		l.vict = l.base;
380 		iotlb_lock_set(obj, &l);
381 	}
382 
383 	cr = iotlb_alloc_cr(obj, e);
384 	if (IS_ERR(cr)) {
385 		pm_runtime_put_sync(obj->dev);
386 		return PTR_ERR(cr);
387 	}
388 
389 	iotlb_load_cr(obj, cr);
390 	kfree(cr);
391 
392 	if (e->prsvd)
393 		l.base++;
394 	/* increment victim for next tlb load */
395 	if (++l.vict == obj->nr_tlb_entries)
396 		l.vict = l.base;
397 	iotlb_lock_set(obj, &l);
398 out:
399 	pm_runtime_put_sync(obj->dev);
400 	return err;
401 }
402 
403 #else /* !PREFETCH_IOTLB */
404 
405 static int load_iotlb_entry(struct omap_iommu *obj, struct iotlb_entry *e)
406 {
407 	return 0;
408 }
409 
410 #endif /* !PREFETCH_IOTLB */
411 
412 static int prefetch_iotlb_entry(struct omap_iommu *obj, struct iotlb_entry *e)
413 {
414 	return load_iotlb_entry(obj, e);
415 }
416 
417 /**
418  * flush_iotlb_page - Clear an iommu tlb entry
419  * @obj:	target iommu
420  * @da:		iommu device virtual address
421  *
422  * Clear an iommu tlb entry which includes 'da' address.
423  **/
424 static void flush_iotlb_page(struct omap_iommu *obj, u32 da)
425 {
426 	int i;
427 	struct cr_regs cr;
428 
429 	pm_runtime_get_sync(obj->dev);
430 
431 	for_each_iotlb_cr(obj, obj->nr_tlb_entries, i, cr) {
432 		u32 start;
433 		size_t bytes;
434 
435 		if (!iotlb_cr_valid(&cr))
436 			continue;
437 
438 		start = iotlb_cr_to_virt(&cr);
439 		bytes = iopgsz_to_bytes(cr.cam & 3);
440 
441 		if ((start <= da) && (da < start + bytes)) {
442 			dev_dbg(obj->dev, "%s: %08x<=%08x(%x)\n",
443 				__func__, start, da, bytes);
444 			iotlb_load_cr(obj, &cr);
445 			iommu_write_reg(obj, 1, MMU_FLUSH_ENTRY);
446 			break;
447 		}
448 	}
449 	pm_runtime_put_sync(obj->dev);
450 
451 	if (i == obj->nr_tlb_entries)
452 		dev_dbg(obj->dev, "%s: no page for %08x\n", __func__, da);
453 }
454 
455 /**
456  * flush_iotlb_all - Clear all iommu tlb entries
457  * @obj:	target iommu
458  **/
459 static void flush_iotlb_all(struct omap_iommu *obj)
460 {
461 	struct iotlb_lock l;
462 
463 	pm_runtime_get_sync(obj->dev);
464 
465 	l.base = 0;
466 	l.vict = 0;
467 	iotlb_lock_set(obj, &l);
468 
469 	iommu_write_reg(obj, 1, MMU_GFLUSH);
470 
471 	pm_runtime_put_sync(obj->dev);
472 }
473 
474 /*
475  *	H/W pagetable operations
476  */
477 static void flush_iopte_range(struct device *dev, dma_addr_t dma,
478 			      unsigned long offset, int num_entries)
479 {
480 	size_t size = num_entries * sizeof(u32);
481 
482 	dma_sync_single_range_for_device(dev, dma, offset, size, DMA_TO_DEVICE);
483 }
484 
485 static void iopte_free(struct omap_iommu *obj, u32 *iopte, bool dma_valid)
486 {
487 	dma_addr_t pt_dma;
488 
489 	/* Note: freed iopte's must be clean ready for re-use */
490 	if (iopte) {
491 		if (dma_valid) {
492 			pt_dma = virt_to_phys(iopte);
493 			dma_unmap_single(obj->dev, pt_dma, IOPTE_TABLE_SIZE,
494 					 DMA_TO_DEVICE);
495 		}
496 
497 		kmem_cache_free(iopte_cachep, iopte);
498 	}
499 }
500 
501 static u32 *iopte_alloc(struct omap_iommu *obj, u32 *iopgd,
502 			dma_addr_t *pt_dma, u32 da)
503 {
504 	u32 *iopte;
505 	unsigned long offset = iopgd_index(da) * sizeof(da);
506 
507 	/* a table has already existed */
508 	if (*iopgd)
509 		goto pte_ready;
510 
511 	/*
512 	 * do the allocation outside the page table lock
513 	 */
514 	spin_unlock(&obj->page_table_lock);
515 	iopte = kmem_cache_zalloc(iopte_cachep, GFP_KERNEL);
516 	spin_lock(&obj->page_table_lock);
517 
518 	if (!*iopgd) {
519 		if (!iopte)
520 			return ERR_PTR(-ENOMEM);
521 
522 		*pt_dma = dma_map_single(obj->dev, iopte, IOPTE_TABLE_SIZE,
523 					 DMA_TO_DEVICE);
524 		if (dma_mapping_error(obj->dev, *pt_dma)) {
525 			dev_err(obj->dev, "DMA map error for L2 table\n");
526 			iopte_free(obj, iopte, false);
527 			return ERR_PTR(-ENOMEM);
528 		}
529 
530 		/*
531 		 * we rely on dma address and the physical address to be
532 		 * the same for mapping the L2 table
533 		 */
534 		if (WARN_ON(*pt_dma != virt_to_phys(iopte))) {
535 			dev_err(obj->dev, "DMA translation error for L2 table\n");
536 			dma_unmap_single(obj->dev, *pt_dma, IOPTE_TABLE_SIZE,
537 					 DMA_TO_DEVICE);
538 			iopte_free(obj, iopte, false);
539 			return ERR_PTR(-ENOMEM);
540 		}
541 
542 		*iopgd = virt_to_phys(iopte) | IOPGD_TABLE;
543 
544 		flush_iopte_range(obj->dev, obj->pd_dma, offset, 1);
545 		dev_vdbg(obj->dev, "%s: a new pte:%p\n", __func__, iopte);
546 	} else {
547 		/* We raced, free the reduniovant table */
548 		iopte_free(obj, iopte, false);
549 	}
550 
551 pte_ready:
552 	iopte = iopte_offset(iopgd, da);
553 	*pt_dma = iopgd_page_paddr(iopgd);
554 	dev_vdbg(obj->dev,
555 		 "%s: da:%08x pgd:%p *pgd:%08x pte:%p *pte:%08x\n",
556 		 __func__, da, iopgd, *iopgd, iopte, *iopte);
557 
558 	return iopte;
559 }
560 
561 static int iopgd_alloc_section(struct omap_iommu *obj, u32 da, u32 pa, u32 prot)
562 {
563 	u32 *iopgd = iopgd_offset(obj, da);
564 	unsigned long offset = iopgd_index(da) * sizeof(da);
565 
566 	if ((da | pa) & ~IOSECTION_MASK) {
567 		dev_err(obj->dev, "%s: %08x:%08x should aligned on %08lx\n",
568 			__func__, da, pa, IOSECTION_SIZE);
569 		return -EINVAL;
570 	}
571 
572 	*iopgd = (pa & IOSECTION_MASK) | prot | IOPGD_SECTION;
573 	flush_iopte_range(obj->dev, obj->pd_dma, offset, 1);
574 	return 0;
575 }
576 
577 static int iopgd_alloc_super(struct omap_iommu *obj, u32 da, u32 pa, u32 prot)
578 {
579 	u32 *iopgd = iopgd_offset(obj, da);
580 	unsigned long offset = iopgd_index(da) * sizeof(da);
581 	int i;
582 
583 	if ((da | pa) & ~IOSUPER_MASK) {
584 		dev_err(obj->dev, "%s: %08x:%08x should aligned on %08lx\n",
585 			__func__, da, pa, IOSUPER_SIZE);
586 		return -EINVAL;
587 	}
588 
589 	for (i = 0; i < 16; i++)
590 		*(iopgd + i) = (pa & IOSUPER_MASK) | prot | IOPGD_SUPER;
591 	flush_iopte_range(obj->dev, obj->pd_dma, offset, 16);
592 	return 0;
593 }
594 
595 static int iopte_alloc_page(struct omap_iommu *obj, u32 da, u32 pa, u32 prot)
596 {
597 	u32 *iopgd = iopgd_offset(obj, da);
598 	dma_addr_t pt_dma;
599 	u32 *iopte = iopte_alloc(obj, iopgd, &pt_dma, da);
600 	unsigned long offset = iopte_index(da) * sizeof(da);
601 
602 	if (IS_ERR(iopte))
603 		return PTR_ERR(iopte);
604 
605 	*iopte = (pa & IOPAGE_MASK) | prot | IOPTE_SMALL;
606 	flush_iopte_range(obj->dev, pt_dma, offset, 1);
607 
608 	dev_vdbg(obj->dev, "%s: da:%08x pa:%08x pte:%p *pte:%08x\n",
609 		 __func__, da, pa, iopte, *iopte);
610 
611 	return 0;
612 }
613 
614 static int iopte_alloc_large(struct omap_iommu *obj, u32 da, u32 pa, u32 prot)
615 {
616 	u32 *iopgd = iopgd_offset(obj, da);
617 	dma_addr_t pt_dma;
618 	u32 *iopte = iopte_alloc(obj, iopgd, &pt_dma, da);
619 	unsigned long offset = iopte_index(da) * sizeof(da);
620 	int i;
621 
622 	if ((da | pa) & ~IOLARGE_MASK) {
623 		dev_err(obj->dev, "%s: %08x:%08x should aligned on %08lx\n",
624 			__func__, da, pa, IOLARGE_SIZE);
625 		return -EINVAL;
626 	}
627 
628 	if (IS_ERR(iopte))
629 		return PTR_ERR(iopte);
630 
631 	for (i = 0; i < 16; i++)
632 		*(iopte + i) = (pa & IOLARGE_MASK) | prot | IOPTE_LARGE;
633 	flush_iopte_range(obj->dev, pt_dma, offset, 16);
634 	return 0;
635 }
636 
637 static int
638 iopgtable_store_entry_core(struct omap_iommu *obj, struct iotlb_entry *e)
639 {
640 	int (*fn)(struct omap_iommu *, u32, u32, u32);
641 	u32 prot;
642 	int err;
643 
644 	if (!obj || !e)
645 		return -EINVAL;
646 
647 	switch (e->pgsz) {
648 	case MMU_CAM_PGSZ_16M:
649 		fn = iopgd_alloc_super;
650 		break;
651 	case MMU_CAM_PGSZ_1M:
652 		fn = iopgd_alloc_section;
653 		break;
654 	case MMU_CAM_PGSZ_64K:
655 		fn = iopte_alloc_large;
656 		break;
657 	case MMU_CAM_PGSZ_4K:
658 		fn = iopte_alloc_page;
659 		break;
660 	default:
661 		fn = NULL;
662 		break;
663 	}
664 
665 	if (WARN_ON(!fn))
666 		return -EINVAL;
667 
668 	prot = get_iopte_attr(e);
669 
670 	spin_lock(&obj->page_table_lock);
671 	err = fn(obj, e->da, e->pa, prot);
672 	spin_unlock(&obj->page_table_lock);
673 
674 	return err;
675 }
676 
677 /**
678  * omap_iopgtable_store_entry - Make an iommu pte entry
679  * @obj:	target iommu
680  * @e:		an iommu tlb entry info
681  **/
682 static int
683 omap_iopgtable_store_entry(struct omap_iommu *obj, struct iotlb_entry *e)
684 {
685 	int err;
686 
687 	flush_iotlb_page(obj, e->da);
688 	err = iopgtable_store_entry_core(obj, e);
689 	if (!err)
690 		prefetch_iotlb_entry(obj, e);
691 	return err;
692 }
693 
694 /**
695  * iopgtable_lookup_entry - Lookup an iommu pte entry
696  * @obj:	target iommu
697  * @da:		iommu device virtual address
698  * @ppgd:	iommu pgd entry pointer to be returned
699  * @ppte:	iommu pte entry pointer to be returned
700  **/
701 static void
702 iopgtable_lookup_entry(struct omap_iommu *obj, u32 da, u32 **ppgd, u32 **ppte)
703 {
704 	u32 *iopgd, *iopte = NULL;
705 
706 	iopgd = iopgd_offset(obj, da);
707 	if (!*iopgd)
708 		goto out;
709 
710 	if (iopgd_is_table(*iopgd))
711 		iopte = iopte_offset(iopgd, da);
712 out:
713 	*ppgd = iopgd;
714 	*ppte = iopte;
715 }
716 
717 static size_t iopgtable_clear_entry_core(struct omap_iommu *obj, u32 da)
718 {
719 	size_t bytes;
720 	u32 *iopgd = iopgd_offset(obj, da);
721 	int nent = 1;
722 	dma_addr_t pt_dma;
723 	unsigned long pd_offset = iopgd_index(da) * sizeof(da);
724 	unsigned long pt_offset = iopte_index(da) * sizeof(da);
725 
726 	if (!*iopgd)
727 		return 0;
728 
729 	if (iopgd_is_table(*iopgd)) {
730 		int i;
731 		u32 *iopte = iopte_offset(iopgd, da);
732 
733 		bytes = IOPTE_SIZE;
734 		if (*iopte & IOPTE_LARGE) {
735 			nent *= 16;
736 			/* rewind to the 1st entry */
737 			iopte = iopte_offset(iopgd, (da & IOLARGE_MASK));
738 		}
739 		bytes *= nent;
740 		memset(iopte, 0, nent * sizeof(*iopte));
741 		pt_dma = iopgd_page_paddr(iopgd);
742 		flush_iopte_range(obj->dev, pt_dma, pt_offset, nent);
743 
744 		/*
745 		 * do table walk to check if this table is necessary or not
746 		 */
747 		iopte = iopte_offset(iopgd, 0);
748 		for (i = 0; i < PTRS_PER_IOPTE; i++)
749 			if (iopte[i])
750 				goto out;
751 
752 		iopte_free(obj, iopte, true);
753 		nent = 1; /* for the next L1 entry */
754 	} else {
755 		bytes = IOPGD_SIZE;
756 		if ((*iopgd & IOPGD_SUPER) == IOPGD_SUPER) {
757 			nent *= 16;
758 			/* rewind to the 1st entry */
759 			iopgd = iopgd_offset(obj, (da & IOSUPER_MASK));
760 		}
761 		bytes *= nent;
762 	}
763 	memset(iopgd, 0, nent * sizeof(*iopgd));
764 	flush_iopte_range(obj->dev, obj->pd_dma, pd_offset, nent);
765 out:
766 	return bytes;
767 }
768 
769 /**
770  * iopgtable_clear_entry - Remove an iommu pte entry
771  * @obj:	target iommu
772  * @da:		iommu device virtual address
773  **/
774 static size_t iopgtable_clear_entry(struct omap_iommu *obj, u32 da)
775 {
776 	size_t bytes;
777 
778 	spin_lock(&obj->page_table_lock);
779 
780 	bytes = iopgtable_clear_entry_core(obj, da);
781 	flush_iotlb_page(obj, da);
782 
783 	spin_unlock(&obj->page_table_lock);
784 
785 	return bytes;
786 }
787 
788 static void iopgtable_clear_entry_all(struct omap_iommu *obj)
789 {
790 	unsigned long offset;
791 	int i;
792 
793 	spin_lock(&obj->page_table_lock);
794 
795 	for (i = 0; i < PTRS_PER_IOPGD; i++) {
796 		u32 da;
797 		u32 *iopgd;
798 
799 		da = i << IOPGD_SHIFT;
800 		iopgd = iopgd_offset(obj, da);
801 		offset = iopgd_index(da) * sizeof(da);
802 
803 		if (!*iopgd)
804 			continue;
805 
806 		if (iopgd_is_table(*iopgd))
807 			iopte_free(obj, iopte_offset(iopgd, 0), true);
808 
809 		*iopgd = 0;
810 		flush_iopte_range(obj->dev, obj->pd_dma, offset, 1);
811 	}
812 
813 	flush_iotlb_all(obj);
814 
815 	spin_unlock(&obj->page_table_lock);
816 }
817 
818 /*
819  *	Device IOMMU generic operations
820  */
821 static irqreturn_t iommu_fault_handler(int irq, void *data)
822 {
823 	u32 da, errs;
824 	u32 *iopgd, *iopte;
825 	struct omap_iommu *obj = data;
826 	struct iommu_domain *domain = obj->domain;
827 	struct omap_iommu_domain *omap_domain = to_omap_domain(domain);
828 
829 	if (!omap_domain->dev)
830 		return IRQ_NONE;
831 
832 	errs = iommu_report_fault(obj, &da);
833 	if (errs == 0)
834 		return IRQ_HANDLED;
835 
836 	/* Fault callback or TLB/PTE Dynamic loading */
837 	if (!report_iommu_fault(domain, obj->dev, da, 0))
838 		return IRQ_HANDLED;
839 
840 	iommu_write_reg(obj, 0, MMU_IRQENABLE);
841 
842 	iopgd = iopgd_offset(obj, da);
843 
844 	if (!iopgd_is_table(*iopgd)) {
845 		dev_err(obj->dev, "%s: errs:0x%08x da:0x%08x pgd:0x%p *pgd:px%08x\n",
846 			obj->name, errs, da, iopgd, *iopgd);
847 		return IRQ_NONE;
848 	}
849 
850 	iopte = iopte_offset(iopgd, da);
851 
852 	dev_err(obj->dev, "%s: errs:0x%08x da:0x%08x pgd:0x%p *pgd:0x%08x pte:0x%p *pte:0x%08x\n",
853 		obj->name, errs, da, iopgd, *iopgd, iopte, *iopte);
854 
855 	return IRQ_NONE;
856 }
857 
858 /**
859  * omap_iommu_attach() - attach iommu device to an iommu domain
860  * @obj:	target omap iommu device
861  * @iopgd:	page table
862  **/
863 static int omap_iommu_attach(struct omap_iommu *obj, u32 *iopgd)
864 {
865 	int err;
866 
867 	spin_lock(&obj->iommu_lock);
868 
869 	obj->pd_dma = dma_map_single(obj->dev, iopgd, IOPGD_TABLE_SIZE,
870 				     DMA_TO_DEVICE);
871 	if (dma_mapping_error(obj->dev, obj->pd_dma)) {
872 		dev_err(obj->dev, "DMA map error for L1 table\n");
873 		err = -ENOMEM;
874 		goto out_err;
875 	}
876 
877 	obj->iopgd = iopgd;
878 	err = iommu_enable(obj);
879 	if (err)
880 		goto out_err;
881 	flush_iotlb_all(obj);
882 
883 	spin_unlock(&obj->iommu_lock);
884 
885 	dev_dbg(obj->dev, "%s: %s\n", __func__, obj->name);
886 
887 	return 0;
888 
889 out_err:
890 	spin_unlock(&obj->iommu_lock);
891 
892 	return err;
893 }
894 
895 /**
896  * omap_iommu_detach - release iommu device
897  * @obj:	target iommu
898  **/
899 static void omap_iommu_detach(struct omap_iommu *obj)
900 {
901 	if (!obj || IS_ERR(obj))
902 		return;
903 
904 	spin_lock(&obj->iommu_lock);
905 
906 	dma_unmap_single(obj->dev, obj->pd_dma, IOPGD_TABLE_SIZE,
907 			 DMA_TO_DEVICE);
908 	iommu_disable(obj);
909 	obj->pd_dma = 0;
910 	obj->iopgd = NULL;
911 
912 	spin_unlock(&obj->iommu_lock);
913 
914 	dev_dbg(obj->dev, "%s: %s\n", __func__, obj->name);
915 }
916 
917 static bool omap_iommu_can_register(struct platform_device *pdev)
918 {
919 	struct device_node *np = pdev->dev.of_node;
920 
921 	if (!of_device_is_compatible(np, "ti,dra7-dsp-iommu"))
922 		return true;
923 
924 	/*
925 	 * restrict IOMMU core registration only for processor-port MDMA MMUs
926 	 * on DRA7 DSPs
927 	 */
928 	if ((!strcmp(dev_name(&pdev->dev), "40d01000.mmu")) ||
929 	    (!strcmp(dev_name(&pdev->dev), "41501000.mmu")))
930 		return true;
931 
932 	return false;
933 }
934 
935 static int omap_iommu_dra7_get_dsp_system_cfg(struct platform_device *pdev,
936 					      struct omap_iommu *obj)
937 {
938 	struct device_node *np = pdev->dev.of_node;
939 	int ret;
940 
941 	if (!of_device_is_compatible(np, "ti,dra7-dsp-iommu"))
942 		return 0;
943 
944 	if (!of_property_read_bool(np, "ti,syscon-mmuconfig")) {
945 		dev_err(&pdev->dev, "ti,syscon-mmuconfig property is missing\n");
946 		return -EINVAL;
947 	}
948 
949 	obj->syscfg =
950 		syscon_regmap_lookup_by_phandle(np, "ti,syscon-mmuconfig");
951 	if (IS_ERR(obj->syscfg)) {
952 		/* can fail with -EPROBE_DEFER */
953 		ret = PTR_ERR(obj->syscfg);
954 		return ret;
955 	}
956 
957 	if (of_property_read_u32_index(np, "ti,syscon-mmuconfig", 1,
958 				       &obj->id)) {
959 		dev_err(&pdev->dev, "couldn't get the IOMMU instance id within subsystem\n");
960 		return -EINVAL;
961 	}
962 
963 	if (obj->id != 0 && obj->id != 1) {
964 		dev_err(&pdev->dev, "invalid IOMMU instance id\n");
965 		return -EINVAL;
966 	}
967 
968 	return 0;
969 }
970 
971 /*
972  *	OMAP Device MMU(IOMMU) detection
973  */
974 static int omap_iommu_probe(struct platform_device *pdev)
975 {
976 	int err = -ENODEV;
977 	int irq;
978 	struct omap_iommu *obj;
979 	struct resource *res;
980 	struct device_node *of = pdev->dev.of_node;
981 
982 	if (!of) {
983 		pr_err("%s: only DT-based devices are supported\n", __func__);
984 		return -ENODEV;
985 	}
986 
987 	obj = devm_kzalloc(&pdev->dev, sizeof(*obj) + MMU_REG_SIZE, GFP_KERNEL);
988 	if (!obj)
989 		return -ENOMEM;
990 
991 	obj->name = dev_name(&pdev->dev);
992 	obj->nr_tlb_entries = 32;
993 	err = of_property_read_u32(of, "ti,#tlb-entries", &obj->nr_tlb_entries);
994 	if (err && err != -EINVAL)
995 		return err;
996 	if (obj->nr_tlb_entries != 32 && obj->nr_tlb_entries != 8)
997 		return -EINVAL;
998 	if (of_find_property(of, "ti,iommu-bus-err-back", NULL))
999 		obj->has_bus_err_back = MMU_GP_REG_BUS_ERR_BACK_EN;
1000 
1001 	obj->dev = &pdev->dev;
1002 	obj->ctx = (void *)obj + sizeof(*obj);
1003 
1004 	spin_lock_init(&obj->iommu_lock);
1005 	spin_lock_init(&obj->page_table_lock);
1006 
1007 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1008 	obj->regbase = devm_ioremap_resource(obj->dev, res);
1009 	if (IS_ERR(obj->regbase))
1010 		return PTR_ERR(obj->regbase);
1011 
1012 	err = omap_iommu_dra7_get_dsp_system_cfg(pdev, obj);
1013 	if (err)
1014 		return err;
1015 
1016 	irq = platform_get_irq(pdev, 0);
1017 	if (irq < 0)
1018 		return -ENODEV;
1019 
1020 	err = devm_request_irq(obj->dev, irq, iommu_fault_handler, IRQF_SHARED,
1021 			       dev_name(obj->dev), obj);
1022 	if (err < 0)
1023 		return err;
1024 	platform_set_drvdata(pdev, obj);
1025 
1026 	if (omap_iommu_can_register(pdev)) {
1027 		obj->group = iommu_group_alloc();
1028 		if (IS_ERR(obj->group))
1029 			return PTR_ERR(obj->group);
1030 
1031 		err = iommu_device_sysfs_add(&obj->iommu, obj->dev, NULL,
1032 					     obj->name);
1033 		if (err)
1034 			goto out_group;
1035 
1036 		iommu_device_set_ops(&obj->iommu, &omap_iommu_ops);
1037 
1038 		err = iommu_device_register(&obj->iommu);
1039 		if (err)
1040 			goto out_sysfs;
1041 	}
1042 
1043 	pm_runtime_irq_safe(obj->dev);
1044 	pm_runtime_enable(obj->dev);
1045 
1046 	omap_iommu_debugfs_add(obj);
1047 
1048 	dev_info(&pdev->dev, "%s registered\n", obj->name);
1049 
1050 	return 0;
1051 
1052 out_sysfs:
1053 	iommu_device_sysfs_remove(&obj->iommu);
1054 out_group:
1055 	iommu_group_put(obj->group);
1056 	return err;
1057 }
1058 
1059 static int omap_iommu_remove(struct platform_device *pdev)
1060 {
1061 	struct omap_iommu *obj = platform_get_drvdata(pdev);
1062 
1063 	if (obj->group) {
1064 		iommu_group_put(obj->group);
1065 		obj->group = NULL;
1066 
1067 		iommu_device_sysfs_remove(&obj->iommu);
1068 		iommu_device_unregister(&obj->iommu);
1069 	}
1070 
1071 	omap_iommu_debugfs_remove(obj);
1072 
1073 	pm_runtime_disable(obj->dev);
1074 
1075 	dev_info(&pdev->dev, "%s removed\n", obj->name);
1076 	return 0;
1077 }
1078 
1079 static const struct of_device_id omap_iommu_of_match[] = {
1080 	{ .compatible = "ti,omap2-iommu" },
1081 	{ .compatible = "ti,omap4-iommu" },
1082 	{ .compatible = "ti,dra7-iommu"	},
1083 	{ .compatible = "ti,dra7-dsp-iommu" },
1084 	{},
1085 };
1086 
1087 static struct platform_driver omap_iommu_driver = {
1088 	.probe	= omap_iommu_probe,
1089 	.remove	= omap_iommu_remove,
1090 	.driver	= {
1091 		.name	= "omap-iommu",
1092 		.of_match_table = of_match_ptr(omap_iommu_of_match),
1093 	},
1094 };
1095 
1096 static u32 iotlb_init_entry(struct iotlb_entry *e, u32 da, u32 pa, int pgsz)
1097 {
1098 	memset(e, 0, sizeof(*e));
1099 
1100 	e->da		= da;
1101 	e->pa		= pa;
1102 	e->valid	= MMU_CAM_V;
1103 	e->pgsz		= pgsz;
1104 	e->endian	= MMU_RAM_ENDIAN_LITTLE;
1105 	e->elsz		= MMU_RAM_ELSZ_8;
1106 	e->mixed	= 0;
1107 
1108 	return iopgsz_to_bytes(e->pgsz);
1109 }
1110 
1111 static int omap_iommu_map(struct iommu_domain *domain, unsigned long da,
1112 			  phys_addr_t pa, size_t bytes, int prot)
1113 {
1114 	struct omap_iommu_domain *omap_domain = to_omap_domain(domain);
1115 	struct device *dev = omap_domain->dev;
1116 	struct omap_iommu_device *iommu;
1117 	struct omap_iommu *oiommu;
1118 	struct iotlb_entry e;
1119 	int omap_pgsz;
1120 	u32 ret = -EINVAL;
1121 	int i;
1122 
1123 	omap_pgsz = bytes_to_iopgsz(bytes);
1124 	if (omap_pgsz < 0) {
1125 		dev_err(dev, "invalid size to map: %d\n", bytes);
1126 		return -EINVAL;
1127 	}
1128 
1129 	dev_dbg(dev, "mapping da 0x%lx to pa %pa size 0x%x\n", da, &pa, bytes);
1130 
1131 	iotlb_init_entry(&e, da, pa, omap_pgsz);
1132 
1133 	iommu = omap_domain->iommus;
1134 	for (i = 0; i < omap_domain->num_iommus; i++, iommu++) {
1135 		oiommu = iommu->iommu_dev;
1136 		ret = omap_iopgtable_store_entry(oiommu, &e);
1137 		if (ret) {
1138 			dev_err(dev, "omap_iopgtable_store_entry failed: %d\n",
1139 				ret);
1140 			break;
1141 		}
1142 	}
1143 
1144 	if (ret) {
1145 		while (i--) {
1146 			iommu--;
1147 			oiommu = iommu->iommu_dev;
1148 			iopgtable_clear_entry(oiommu, da);
1149 		}
1150 	}
1151 
1152 	return ret;
1153 }
1154 
1155 static size_t omap_iommu_unmap(struct iommu_domain *domain, unsigned long da,
1156 			       size_t size)
1157 {
1158 	struct omap_iommu_domain *omap_domain = to_omap_domain(domain);
1159 	struct device *dev = omap_domain->dev;
1160 	struct omap_iommu_device *iommu;
1161 	struct omap_iommu *oiommu;
1162 	bool error = false;
1163 	size_t bytes = 0;
1164 	int i;
1165 
1166 	dev_dbg(dev, "unmapping da 0x%lx size %u\n", da, size);
1167 
1168 	iommu = omap_domain->iommus;
1169 	for (i = 0; i < omap_domain->num_iommus; i++, iommu++) {
1170 		oiommu = iommu->iommu_dev;
1171 		bytes = iopgtable_clear_entry(oiommu, da);
1172 		if (!bytes)
1173 			error = true;
1174 	}
1175 
1176 	/*
1177 	 * simplify return - we are only checking if any of the iommus
1178 	 * reported an error, but not if all of them are unmapping the
1179 	 * same number of entries. This should not occur due to the
1180 	 * mirror programming.
1181 	 */
1182 	return error ? 0 : bytes;
1183 }
1184 
1185 static int omap_iommu_count(struct device *dev)
1186 {
1187 	struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
1188 	int count = 0;
1189 
1190 	while (arch_data->iommu_dev) {
1191 		count++;
1192 		arch_data++;
1193 	}
1194 
1195 	return count;
1196 }
1197 
1198 /* caller should call cleanup if this function fails */
1199 static int omap_iommu_attach_init(struct device *dev,
1200 				  struct omap_iommu_domain *odomain)
1201 {
1202 	struct omap_iommu_device *iommu;
1203 	int i;
1204 
1205 	odomain->num_iommus = omap_iommu_count(dev);
1206 	if (!odomain->num_iommus)
1207 		return -EINVAL;
1208 
1209 	odomain->iommus = kcalloc(odomain->num_iommus, sizeof(*iommu),
1210 				  GFP_ATOMIC);
1211 	if (!odomain->iommus)
1212 		return -ENOMEM;
1213 
1214 	iommu = odomain->iommus;
1215 	for (i = 0; i < odomain->num_iommus; i++, iommu++) {
1216 		iommu->pgtable = kzalloc(IOPGD_TABLE_SIZE, GFP_ATOMIC);
1217 		if (!iommu->pgtable)
1218 			return -ENOMEM;
1219 
1220 		/*
1221 		 * should never fail, but please keep this around to ensure
1222 		 * we keep the hardware happy
1223 		 */
1224 		if (WARN_ON(!IS_ALIGNED((long)iommu->pgtable,
1225 					IOPGD_TABLE_SIZE)))
1226 			return -EINVAL;
1227 	}
1228 
1229 	return 0;
1230 }
1231 
1232 static void omap_iommu_detach_fini(struct omap_iommu_domain *odomain)
1233 {
1234 	int i;
1235 	struct omap_iommu_device *iommu = odomain->iommus;
1236 
1237 	for (i = 0; iommu && i < odomain->num_iommus; i++, iommu++)
1238 		kfree(iommu->pgtable);
1239 
1240 	kfree(odomain->iommus);
1241 	odomain->num_iommus = 0;
1242 	odomain->iommus = NULL;
1243 }
1244 
1245 static int
1246 omap_iommu_attach_dev(struct iommu_domain *domain, struct device *dev)
1247 {
1248 	struct omap_iommu_domain *omap_domain = to_omap_domain(domain);
1249 	struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
1250 	struct omap_iommu_device *iommu;
1251 	struct omap_iommu *oiommu;
1252 	int ret = 0;
1253 	int i;
1254 
1255 	if (!arch_data || !arch_data->iommu_dev) {
1256 		dev_err(dev, "device doesn't have an associated iommu\n");
1257 		return -EINVAL;
1258 	}
1259 
1260 	spin_lock(&omap_domain->lock);
1261 
1262 	/* only a single client device can be attached to a domain */
1263 	if (omap_domain->dev) {
1264 		dev_err(dev, "iommu domain is already attached\n");
1265 		ret = -EBUSY;
1266 		goto out;
1267 	}
1268 
1269 	ret = omap_iommu_attach_init(dev, omap_domain);
1270 	if (ret) {
1271 		dev_err(dev, "failed to allocate required iommu data %d\n",
1272 			ret);
1273 		goto init_fail;
1274 	}
1275 
1276 	iommu = omap_domain->iommus;
1277 	for (i = 0; i < omap_domain->num_iommus; i++, iommu++, arch_data++) {
1278 		/* configure and enable the omap iommu */
1279 		oiommu = arch_data->iommu_dev;
1280 		ret = omap_iommu_attach(oiommu, iommu->pgtable);
1281 		if (ret) {
1282 			dev_err(dev, "can't get omap iommu: %d\n", ret);
1283 			goto attach_fail;
1284 		}
1285 
1286 		oiommu->domain = domain;
1287 		iommu->iommu_dev = oiommu;
1288 	}
1289 
1290 	omap_domain->dev = dev;
1291 
1292 	goto out;
1293 
1294 attach_fail:
1295 	while (i--) {
1296 		iommu--;
1297 		arch_data--;
1298 		oiommu = iommu->iommu_dev;
1299 		omap_iommu_detach(oiommu);
1300 		iommu->iommu_dev = NULL;
1301 		oiommu->domain = NULL;
1302 	}
1303 init_fail:
1304 	omap_iommu_detach_fini(omap_domain);
1305 out:
1306 	spin_unlock(&omap_domain->lock);
1307 	return ret;
1308 }
1309 
1310 static void _omap_iommu_detach_dev(struct omap_iommu_domain *omap_domain,
1311 				   struct device *dev)
1312 {
1313 	struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
1314 	struct omap_iommu_device *iommu = omap_domain->iommus;
1315 	struct omap_iommu *oiommu;
1316 	int i;
1317 
1318 	if (!omap_domain->dev) {
1319 		dev_err(dev, "domain has no attached device\n");
1320 		return;
1321 	}
1322 
1323 	/* only a single device is supported per domain for now */
1324 	if (omap_domain->dev != dev) {
1325 		dev_err(dev, "invalid attached device\n");
1326 		return;
1327 	}
1328 
1329 	/*
1330 	 * cleanup in the reverse order of attachment - this addresses
1331 	 * any h/w dependencies between multiple instances, if any
1332 	 */
1333 	iommu += (omap_domain->num_iommus - 1);
1334 	arch_data += (omap_domain->num_iommus - 1);
1335 	for (i = 0; i < omap_domain->num_iommus; i++, iommu--, arch_data--) {
1336 		oiommu = iommu->iommu_dev;
1337 		iopgtable_clear_entry_all(oiommu);
1338 
1339 		omap_iommu_detach(oiommu);
1340 		iommu->iommu_dev = NULL;
1341 		oiommu->domain = NULL;
1342 	}
1343 
1344 	omap_iommu_detach_fini(omap_domain);
1345 
1346 	omap_domain->dev = NULL;
1347 }
1348 
1349 static void omap_iommu_detach_dev(struct iommu_domain *domain,
1350 				  struct device *dev)
1351 {
1352 	struct omap_iommu_domain *omap_domain = to_omap_domain(domain);
1353 
1354 	spin_lock(&omap_domain->lock);
1355 	_omap_iommu_detach_dev(omap_domain, dev);
1356 	spin_unlock(&omap_domain->lock);
1357 }
1358 
1359 static struct iommu_domain *omap_iommu_domain_alloc(unsigned type)
1360 {
1361 	struct omap_iommu_domain *omap_domain;
1362 
1363 	if (type != IOMMU_DOMAIN_UNMANAGED)
1364 		return NULL;
1365 
1366 	omap_domain = kzalloc(sizeof(*omap_domain), GFP_KERNEL);
1367 	if (!omap_domain)
1368 		return NULL;
1369 
1370 	spin_lock_init(&omap_domain->lock);
1371 
1372 	omap_domain->domain.geometry.aperture_start = 0;
1373 	omap_domain->domain.geometry.aperture_end   = (1ULL << 32) - 1;
1374 	omap_domain->domain.geometry.force_aperture = true;
1375 
1376 	return &omap_domain->domain;
1377 }
1378 
1379 static void omap_iommu_domain_free(struct iommu_domain *domain)
1380 {
1381 	struct omap_iommu_domain *omap_domain = to_omap_domain(domain);
1382 
1383 	/*
1384 	 * An iommu device is still attached
1385 	 * (currently, only one device can be attached) ?
1386 	 */
1387 	if (omap_domain->dev)
1388 		_omap_iommu_detach_dev(omap_domain, omap_domain->dev);
1389 
1390 	kfree(omap_domain);
1391 }
1392 
1393 static phys_addr_t omap_iommu_iova_to_phys(struct iommu_domain *domain,
1394 					   dma_addr_t da)
1395 {
1396 	struct omap_iommu_domain *omap_domain = to_omap_domain(domain);
1397 	struct omap_iommu_device *iommu = omap_domain->iommus;
1398 	struct omap_iommu *oiommu = iommu->iommu_dev;
1399 	struct device *dev = oiommu->dev;
1400 	u32 *pgd, *pte;
1401 	phys_addr_t ret = 0;
1402 
1403 	/*
1404 	 * all the iommus within the domain will have identical programming,
1405 	 * so perform the lookup using just the first iommu
1406 	 */
1407 	iopgtable_lookup_entry(oiommu, da, &pgd, &pte);
1408 
1409 	if (pte) {
1410 		if (iopte_is_small(*pte))
1411 			ret = omap_iommu_translate(*pte, da, IOPTE_MASK);
1412 		else if (iopte_is_large(*pte))
1413 			ret = omap_iommu_translate(*pte, da, IOLARGE_MASK);
1414 		else
1415 			dev_err(dev, "bogus pte 0x%x, da 0x%llx", *pte,
1416 				(unsigned long long)da);
1417 	} else {
1418 		if (iopgd_is_section(*pgd))
1419 			ret = omap_iommu_translate(*pgd, da, IOSECTION_MASK);
1420 		else if (iopgd_is_super(*pgd))
1421 			ret = omap_iommu_translate(*pgd, da, IOSUPER_MASK);
1422 		else
1423 			dev_err(dev, "bogus pgd 0x%x, da 0x%llx", *pgd,
1424 				(unsigned long long)da);
1425 	}
1426 
1427 	return ret;
1428 }
1429 
1430 static int omap_iommu_add_device(struct device *dev)
1431 {
1432 	struct omap_iommu_arch_data *arch_data, *tmp;
1433 	struct omap_iommu *oiommu;
1434 	struct iommu_group *group;
1435 	struct device_node *np;
1436 	struct platform_device *pdev;
1437 	int num_iommus, i;
1438 	int ret;
1439 
1440 	/*
1441 	 * Allocate the archdata iommu structure for DT-based devices.
1442 	 *
1443 	 * TODO: Simplify this when removing non-DT support completely from the
1444 	 * IOMMU users.
1445 	 */
1446 	if (!dev->of_node)
1447 		return 0;
1448 
1449 	/*
1450 	 * retrieve the count of IOMMU nodes using phandle size as element size
1451 	 * since #iommu-cells = 0 for OMAP
1452 	 */
1453 	num_iommus = of_property_count_elems_of_size(dev->of_node, "iommus",
1454 						     sizeof(phandle));
1455 	if (num_iommus < 0)
1456 		return 0;
1457 
1458 	arch_data = kcalloc(num_iommus + 1, sizeof(*arch_data), GFP_KERNEL);
1459 	if (!arch_data)
1460 		return -ENOMEM;
1461 
1462 	for (i = 0, tmp = arch_data; i < num_iommus; i++, tmp++) {
1463 		np = of_parse_phandle(dev->of_node, "iommus", i);
1464 		if (!np) {
1465 			kfree(arch_data);
1466 			return -EINVAL;
1467 		}
1468 
1469 		pdev = of_find_device_by_node(np);
1470 		if (WARN_ON(!pdev)) {
1471 			of_node_put(np);
1472 			kfree(arch_data);
1473 			return -EINVAL;
1474 		}
1475 
1476 		oiommu = platform_get_drvdata(pdev);
1477 		if (!oiommu) {
1478 			of_node_put(np);
1479 			kfree(arch_data);
1480 			return -EINVAL;
1481 		}
1482 
1483 		tmp->iommu_dev = oiommu;
1484 
1485 		of_node_put(np);
1486 	}
1487 
1488 	/*
1489 	 * use the first IOMMU alone for the sysfs device linking.
1490 	 * TODO: Evaluate if a single iommu_group needs to be
1491 	 * maintained for both IOMMUs
1492 	 */
1493 	oiommu = arch_data->iommu_dev;
1494 	ret = iommu_device_link(&oiommu->iommu, dev);
1495 	if (ret) {
1496 		kfree(arch_data);
1497 		return ret;
1498 	}
1499 
1500 	dev->archdata.iommu = arch_data;
1501 
1502 	/*
1503 	 * IOMMU group initialization calls into omap_iommu_device_group, which
1504 	 * needs a valid dev->archdata.iommu pointer
1505 	 */
1506 	group = iommu_group_get_for_dev(dev);
1507 	if (IS_ERR(group)) {
1508 		iommu_device_unlink(&oiommu->iommu, dev);
1509 		dev->archdata.iommu = NULL;
1510 		kfree(arch_data);
1511 		return PTR_ERR(group);
1512 	}
1513 	iommu_group_put(group);
1514 
1515 	return 0;
1516 }
1517 
1518 static void omap_iommu_remove_device(struct device *dev)
1519 {
1520 	struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
1521 
1522 	if (!dev->of_node || !arch_data)
1523 		return;
1524 
1525 	iommu_device_unlink(&arch_data->iommu_dev->iommu, dev);
1526 	iommu_group_remove_device(dev);
1527 
1528 	dev->archdata.iommu = NULL;
1529 	kfree(arch_data);
1530 
1531 }
1532 
1533 static struct iommu_group *omap_iommu_device_group(struct device *dev)
1534 {
1535 	struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
1536 	struct iommu_group *group = ERR_PTR(-EINVAL);
1537 
1538 	if (arch_data->iommu_dev)
1539 		group = iommu_group_ref_get(arch_data->iommu_dev->group);
1540 
1541 	return group;
1542 }
1543 
1544 static const struct iommu_ops omap_iommu_ops = {
1545 	.domain_alloc	= omap_iommu_domain_alloc,
1546 	.domain_free	= omap_iommu_domain_free,
1547 	.attach_dev	= omap_iommu_attach_dev,
1548 	.detach_dev	= omap_iommu_detach_dev,
1549 	.map		= omap_iommu_map,
1550 	.unmap		= omap_iommu_unmap,
1551 	.iova_to_phys	= omap_iommu_iova_to_phys,
1552 	.add_device	= omap_iommu_add_device,
1553 	.remove_device	= omap_iommu_remove_device,
1554 	.device_group	= omap_iommu_device_group,
1555 	.pgsize_bitmap	= OMAP_IOMMU_PGSIZES,
1556 };
1557 
1558 static int __init omap_iommu_init(void)
1559 {
1560 	struct kmem_cache *p;
1561 	const unsigned long flags = SLAB_HWCACHE_ALIGN;
1562 	size_t align = 1 << 10; /* L2 pagetable alignement */
1563 	struct device_node *np;
1564 	int ret;
1565 
1566 	np = of_find_matching_node(NULL, omap_iommu_of_match);
1567 	if (!np)
1568 		return 0;
1569 
1570 	of_node_put(np);
1571 
1572 	p = kmem_cache_create("iopte_cache", IOPTE_TABLE_SIZE, align, flags,
1573 			      NULL);
1574 	if (!p)
1575 		return -ENOMEM;
1576 	iopte_cachep = p;
1577 
1578 	omap_iommu_debugfs_init();
1579 
1580 	ret = platform_driver_register(&omap_iommu_driver);
1581 	if (ret) {
1582 		pr_err("%s: failed to register driver\n", __func__);
1583 		goto fail_driver;
1584 	}
1585 
1586 	ret = bus_set_iommu(&platform_bus_type, &omap_iommu_ops);
1587 	if (ret)
1588 		goto fail_bus;
1589 
1590 	return 0;
1591 
1592 fail_bus:
1593 	platform_driver_unregister(&omap_iommu_driver);
1594 fail_driver:
1595 	kmem_cache_destroy(iopte_cachep);
1596 	return ret;
1597 }
1598 subsys_initcall(omap_iommu_init);
1599 /* must be ready before omap3isp is probed */
1600