[go: nahoru, domu]

1/*
2 * omap iommu: tlb and pagetable primitives
3 *
4 * Copyright (C) 2008-2010 Nokia Corporation
5 *
6 * Written by Hiroshi DOYU <Hiroshi.DOYU@nokia.com>,
7 *		Paul Mundt and Toshihiro Kobayashi
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
12 */
13
14#include <linux/err.h>
15#include <linux/module.h>
16#include <linux/slab.h>
17#include <linux/interrupt.h>
18#include <linux/ioport.h>
19#include <linux/platform_device.h>
20#include <linux/iommu.h>
21#include <linux/omap-iommu.h>
22#include <linux/mutex.h>
23#include <linux/spinlock.h>
24#include <linux/io.h>
25#include <linux/pm_runtime.h>
26#include <linux/of.h>
27#include <linux/of_iommu.h>
28#include <linux/of_irq.h>
29#include <linux/of_platform.h>
30
31#include <asm/cacheflush.h>
32
33#include <linux/platform_data/iommu-omap.h>
34
35#include "omap-iopgtable.h"
36#include "omap-iommu.h"
37
38#define to_iommu(dev)							\
39	((struct omap_iommu *)platform_get_drvdata(to_platform_device(dev)))
40
41#define for_each_iotlb_cr(obj, n, __i, cr)				\
42	for (__i = 0;							\
43	     (__i < (n)) && (cr = __iotlb_read_cr((obj), __i), true);	\
44	     __i++)
45
46/* bitmap of the page sizes currently supported */
47#define OMAP_IOMMU_PGSIZES	(SZ_4K | SZ_64K | SZ_1M | SZ_16M)
48
49/**
50 * struct omap_iommu_domain - omap iommu domain
51 * @pgtable:	the page table
52 * @iommu_dev:	an omap iommu device attached to this domain. only a single
53 *		iommu device can be attached for now.
54 * @dev:	Device using this domain.
55 * @lock:	domain lock, should be taken when attaching/detaching
56 */
57struct omap_iommu_domain {
58	u32 *pgtable;
59	struct omap_iommu *iommu_dev;
60	struct device *dev;
61	spinlock_t lock;
62};
63
64#define MMU_LOCK_BASE_SHIFT	10
65#define MMU_LOCK_BASE_MASK	(0x1f << MMU_LOCK_BASE_SHIFT)
66#define MMU_LOCK_BASE(x)	\
67	((x & MMU_LOCK_BASE_MASK) >> MMU_LOCK_BASE_SHIFT)
68
69#define MMU_LOCK_VICT_SHIFT	4
70#define MMU_LOCK_VICT_MASK	(0x1f << MMU_LOCK_VICT_SHIFT)
71#define MMU_LOCK_VICT(x)	\
72	((x & MMU_LOCK_VICT_MASK) >> MMU_LOCK_VICT_SHIFT)
73
74struct iotlb_lock {
75	short base;
76	short vict;
77};
78
79/* accommodate the difference between omap1 and omap2/3 */
80static const struct iommu_functions *arch_iommu;
81
82static struct platform_driver omap_iommu_driver;
83static struct kmem_cache *iopte_cachep;
84
85/**
86 * omap_install_iommu_arch - Install archtecure specific iommu functions
87 * @ops:	a pointer to architecture specific iommu functions
88 *
89 * There are several kind of iommu algorithm(tlb, pagetable) among
90 * omap series. This interface installs such an iommu algorighm.
91 **/
92int omap_install_iommu_arch(const struct iommu_functions *ops)
93{
94	if (arch_iommu)
95		return -EBUSY;
96
97	arch_iommu = ops;
98	return 0;
99}
100EXPORT_SYMBOL_GPL(omap_install_iommu_arch);
101
102/**
103 * omap_uninstall_iommu_arch - Uninstall archtecure specific iommu functions
104 * @ops:	a pointer to architecture specific iommu functions
105 *
106 * This interface uninstalls the iommu algorighm installed previously.
107 **/
108void omap_uninstall_iommu_arch(const struct iommu_functions *ops)
109{
110	if (arch_iommu != ops)
111		pr_err("%s: not your arch\n", __func__);
112
113	arch_iommu = NULL;
114}
115EXPORT_SYMBOL_GPL(omap_uninstall_iommu_arch);
116
117/**
118 * omap_iommu_save_ctx - Save registers for pm off-mode support
119 * @dev:	client device
120 **/
121void omap_iommu_save_ctx(struct device *dev)
122{
123	struct omap_iommu *obj = dev_to_omap_iommu(dev);
124
125	arch_iommu->save_ctx(obj);
126}
127EXPORT_SYMBOL_GPL(omap_iommu_save_ctx);
128
129/**
130 * omap_iommu_restore_ctx - Restore registers for pm off-mode support
131 * @dev:	client device
132 **/
133void omap_iommu_restore_ctx(struct device *dev)
134{
135	struct omap_iommu *obj = dev_to_omap_iommu(dev);
136
137	arch_iommu->restore_ctx(obj);
138}
139EXPORT_SYMBOL_GPL(omap_iommu_restore_ctx);
140
141/**
142 * omap_iommu_arch_version - Return running iommu arch version
143 **/
144u32 omap_iommu_arch_version(void)
145{
146	return arch_iommu->version;
147}
148EXPORT_SYMBOL_GPL(omap_iommu_arch_version);
149
150static int iommu_enable(struct omap_iommu *obj)
151{
152	int err;
153	struct platform_device *pdev = to_platform_device(obj->dev);
154	struct iommu_platform_data *pdata = pdev->dev.platform_data;
155
156	if (!arch_iommu)
157		return -ENODEV;
158
159	if (pdata && pdata->deassert_reset) {
160		err = pdata->deassert_reset(pdev, pdata->reset_name);
161		if (err) {
162			dev_err(obj->dev, "deassert_reset failed: %d\n", err);
163			return err;
164		}
165	}
166
167	pm_runtime_get_sync(obj->dev);
168
169	err = arch_iommu->enable(obj);
170
171	return err;
172}
173
174static void iommu_disable(struct omap_iommu *obj)
175{
176	struct platform_device *pdev = to_platform_device(obj->dev);
177	struct iommu_platform_data *pdata = pdev->dev.platform_data;
178
179	arch_iommu->disable(obj);
180
181	pm_runtime_put_sync(obj->dev);
182
183	if (pdata && pdata->assert_reset)
184		pdata->assert_reset(pdev, pdata->reset_name);
185}
186
187/*
188 *	TLB operations
189 */
190void omap_iotlb_cr_to_e(struct cr_regs *cr, struct iotlb_entry *e)
191{
192	BUG_ON(!cr || !e);
193
194	arch_iommu->cr_to_e(cr, e);
195}
196EXPORT_SYMBOL_GPL(omap_iotlb_cr_to_e);
197
198static inline int iotlb_cr_valid(struct cr_regs *cr)
199{
200	if (!cr)
201		return -EINVAL;
202
203	return arch_iommu->cr_valid(cr);
204}
205
206static inline struct cr_regs *iotlb_alloc_cr(struct omap_iommu *obj,
207					     struct iotlb_entry *e)
208{
209	if (!e)
210		return NULL;
211
212	return arch_iommu->alloc_cr(obj, e);
213}
214
215static u32 iotlb_cr_to_virt(struct cr_regs *cr)
216{
217	return arch_iommu->cr_to_virt(cr);
218}
219
220static u32 get_iopte_attr(struct iotlb_entry *e)
221{
222	return arch_iommu->get_pte_attr(e);
223}
224
225static u32 iommu_report_fault(struct omap_iommu *obj, u32 *da)
226{
227	return arch_iommu->fault_isr(obj, da);
228}
229
230static void iotlb_lock_get(struct omap_iommu *obj, struct iotlb_lock *l)
231{
232	u32 val;
233
234	val = iommu_read_reg(obj, MMU_LOCK);
235
236	l->base = MMU_LOCK_BASE(val);
237	l->vict = MMU_LOCK_VICT(val);
238
239}
240
241static void iotlb_lock_set(struct omap_iommu *obj, struct iotlb_lock *l)
242{
243	u32 val;
244
245	val = (l->base << MMU_LOCK_BASE_SHIFT);
246	val |= (l->vict << MMU_LOCK_VICT_SHIFT);
247
248	iommu_write_reg(obj, val, MMU_LOCK);
249}
250
251static void iotlb_read_cr(struct omap_iommu *obj, struct cr_regs *cr)
252{
253	arch_iommu->tlb_read_cr(obj, cr);
254}
255
256static void iotlb_load_cr(struct omap_iommu *obj, struct cr_regs *cr)
257{
258	arch_iommu->tlb_load_cr(obj, cr);
259
260	iommu_write_reg(obj, 1, MMU_FLUSH_ENTRY);
261	iommu_write_reg(obj, 1, MMU_LD_TLB);
262}
263
264/**
265 * iotlb_dump_cr - Dump an iommu tlb entry into buf
266 * @obj:	target iommu
267 * @cr:		contents of cam and ram register
268 * @buf:	output buffer
269 **/
270static inline ssize_t iotlb_dump_cr(struct omap_iommu *obj, struct cr_regs *cr,
271				    char *buf)
272{
273	BUG_ON(!cr || !buf);
274
275	return arch_iommu->dump_cr(obj, cr, buf);
276}
277
278/* only used in iotlb iteration for-loop */
279static struct cr_regs __iotlb_read_cr(struct omap_iommu *obj, int n)
280{
281	struct cr_regs cr;
282	struct iotlb_lock l;
283
284	iotlb_lock_get(obj, &l);
285	l.vict = n;
286	iotlb_lock_set(obj, &l);
287	iotlb_read_cr(obj, &cr);
288
289	return cr;
290}
291
292/**
293 * load_iotlb_entry - Set an iommu tlb entry
294 * @obj:	target iommu
295 * @e:		an iommu tlb entry info
296 **/
297#ifdef PREFETCH_IOTLB
298static int load_iotlb_entry(struct omap_iommu *obj, struct iotlb_entry *e)
299{
300	int err = 0;
301	struct iotlb_lock l;
302	struct cr_regs *cr;
303
304	if (!obj || !obj->nr_tlb_entries || !e)
305		return -EINVAL;
306
307	pm_runtime_get_sync(obj->dev);
308
309	iotlb_lock_get(obj, &l);
310	if (l.base == obj->nr_tlb_entries) {
311		dev_warn(obj->dev, "%s: preserve entries full\n", __func__);
312		err = -EBUSY;
313		goto out;
314	}
315	if (!e->prsvd) {
316		int i;
317		struct cr_regs tmp;
318
319		for_each_iotlb_cr(obj, obj->nr_tlb_entries, i, tmp)
320			if (!iotlb_cr_valid(&tmp))
321				break;
322
323		if (i == obj->nr_tlb_entries) {
324			dev_dbg(obj->dev, "%s: full: no entry\n", __func__);
325			err = -EBUSY;
326			goto out;
327		}
328
329		iotlb_lock_get(obj, &l);
330	} else {
331		l.vict = l.base;
332		iotlb_lock_set(obj, &l);
333	}
334
335	cr = iotlb_alloc_cr(obj, e);
336	if (IS_ERR(cr)) {
337		pm_runtime_put_sync(obj->dev);
338		return PTR_ERR(cr);
339	}
340
341	iotlb_load_cr(obj, cr);
342	kfree(cr);
343
344	if (e->prsvd)
345		l.base++;
346	/* increment victim for next tlb load */
347	if (++l.vict == obj->nr_tlb_entries)
348		l.vict = l.base;
349	iotlb_lock_set(obj, &l);
350out:
351	pm_runtime_put_sync(obj->dev);
352	return err;
353}
354
355#else /* !PREFETCH_IOTLB */
356
357static int load_iotlb_entry(struct omap_iommu *obj, struct iotlb_entry *e)
358{
359	return 0;
360}
361
362#endif /* !PREFETCH_IOTLB */
363
364static int prefetch_iotlb_entry(struct omap_iommu *obj, struct iotlb_entry *e)
365{
366	return load_iotlb_entry(obj, e);
367}
368
369/**
370 * flush_iotlb_page - Clear an iommu tlb entry
371 * @obj:	target iommu
372 * @da:		iommu device virtual address
373 *
374 * Clear an iommu tlb entry which includes 'da' address.
375 **/
376static void flush_iotlb_page(struct omap_iommu *obj, u32 da)
377{
378	int i;
379	struct cr_regs cr;
380
381	pm_runtime_get_sync(obj->dev);
382
383	for_each_iotlb_cr(obj, obj->nr_tlb_entries, i, cr) {
384		u32 start;
385		size_t bytes;
386
387		if (!iotlb_cr_valid(&cr))
388			continue;
389
390		start = iotlb_cr_to_virt(&cr);
391		bytes = iopgsz_to_bytes(cr.cam & 3);
392
393		if ((start <= da) && (da < start + bytes)) {
394			dev_dbg(obj->dev, "%s: %08x<=%08x(%x)\n",
395				__func__, start, da, bytes);
396			iotlb_load_cr(obj, &cr);
397			iommu_write_reg(obj, 1, MMU_FLUSH_ENTRY);
398			break;
399		}
400	}
401	pm_runtime_put_sync(obj->dev);
402
403	if (i == obj->nr_tlb_entries)
404		dev_dbg(obj->dev, "%s: no page for %08x\n", __func__, da);
405}
406
407/**
408 * flush_iotlb_all - Clear all iommu tlb entries
409 * @obj:	target iommu
410 **/
411static void flush_iotlb_all(struct omap_iommu *obj)
412{
413	struct iotlb_lock l;
414
415	pm_runtime_get_sync(obj->dev);
416
417	l.base = 0;
418	l.vict = 0;
419	iotlb_lock_set(obj, &l);
420
421	iommu_write_reg(obj, 1, MMU_GFLUSH);
422
423	pm_runtime_put_sync(obj->dev);
424}
425
426#if defined(CONFIG_OMAP_IOMMU_DEBUG) || defined(CONFIG_OMAP_IOMMU_DEBUG_MODULE)
427
428ssize_t omap_iommu_dump_ctx(struct omap_iommu *obj, char *buf, ssize_t bytes)
429{
430	if (!obj || !buf)
431		return -EINVAL;
432
433	pm_runtime_get_sync(obj->dev);
434
435	bytes = arch_iommu->dump_ctx(obj, buf, bytes);
436
437	pm_runtime_put_sync(obj->dev);
438
439	return bytes;
440}
441EXPORT_SYMBOL_GPL(omap_iommu_dump_ctx);
442
443static int
444__dump_tlb_entries(struct omap_iommu *obj, struct cr_regs *crs, int num)
445{
446	int i;
447	struct iotlb_lock saved;
448	struct cr_regs tmp;
449	struct cr_regs *p = crs;
450
451	pm_runtime_get_sync(obj->dev);
452	iotlb_lock_get(obj, &saved);
453
454	for_each_iotlb_cr(obj, num, i, tmp) {
455		if (!iotlb_cr_valid(&tmp))
456			continue;
457		*p++ = tmp;
458	}
459
460	iotlb_lock_set(obj, &saved);
461	pm_runtime_put_sync(obj->dev);
462
463	return  p - crs;
464}
465
466/**
467 * omap_dump_tlb_entries - dump cr arrays to given buffer
468 * @obj:	target iommu
469 * @buf:	output buffer
470 **/
471size_t omap_dump_tlb_entries(struct omap_iommu *obj, char *buf, ssize_t bytes)
472{
473	int i, num;
474	struct cr_regs *cr;
475	char *p = buf;
476
477	num = bytes / sizeof(*cr);
478	num = min(obj->nr_tlb_entries, num);
479
480	cr = kcalloc(num, sizeof(*cr), GFP_KERNEL);
481	if (!cr)
482		return 0;
483
484	num = __dump_tlb_entries(obj, cr, num);
485	for (i = 0; i < num; i++)
486		p += iotlb_dump_cr(obj, cr + i, p);
487	kfree(cr);
488
489	return p - buf;
490}
491EXPORT_SYMBOL_GPL(omap_dump_tlb_entries);
492
493int omap_foreach_iommu_device(void *data, int (*fn)(struct device *, void *))
494{
495	return driver_for_each_device(&omap_iommu_driver.driver,
496				      NULL, data, fn);
497}
498EXPORT_SYMBOL_GPL(omap_foreach_iommu_device);
499
500#endif /* CONFIG_OMAP_IOMMU_DEBUG_MODULE */
501
502/*
503 *	H/W pagetable operations
504 */
505static void flush_iopgd_range(u32 *first, u32 *last)
506{
507	/* FIXME: L2 cache should be taken care of if it exists */
508	do {
509		asm("mcr	p15, 0, %0, c7, c10, 1 @ flush_pgd"
510		    : : "r" (first));
511		first += L1_CACHE_BYTES / sizeof(*first);
512	} while (first <= last);
513}
514
515static void flush_iopte_range(u32 *first, u32 *last)
516{
517	/* FIXME: L2 cache should be taken care of if it exists */
518	do {
519		asm("mcr	p15, 0, %0, c7, c10, 1 @ flush_pte"
520		    : : "r" (first));
521		first += L1_CACHE_BYTES / sizeof(*first);
522	} while (first <= last);
523}
524
525static void iopte_free(u32 *iopte)
526{
527	/* Note: freed iopte's must be clean ready for re-use */
528	if (iopte)
529		kmem_cache_free(iopte_cachep, iopte);
530}
531
532static u32 *iopte_alloc(struct omap_iommu *obj, u32 *iopgd, u32 da)
533{
534	u32 *iopte;
535
536	/* a table has already existed */
537	if (*iopgd)
538		goto pte_ready;
539
540	/*
541	 * do the allocation outside the page table lock
542	 */
543	spin_unlock(&obj->page_table_lock);
544	iopte = kmem_cache_zalloc(iopte_cachep, GFP_KERNEL);
545	spin_lock(&obj->page_table_lock);
546
547	if (!*iopgd) {
548		if (!iopte)
549			return ERR_PTR(-ENOMEM);
550
551		*iopgd = virt_to_phys(iopte) | IOPGD_TABLE;
552		flush_iopgd_range(iopgd, iopgd);
553
554		dev_vdbg(obj->dev, "%s: a new pte:%p\n", __func__, iopte);
555	} else {
556		/* We raced, free the reduniovant table */
557		iopte_free(iopte);
558	}
559
560pte_ready:
561	iopte = iopte_offset(iopgd, da);
562
563	dev_vdbg(obj->dev,
564		 "%s: da:%08x pgd:%p *pgd:%08x pte:%p *pte:%08x\n",
565		 __func__, da, iopgd, *iopgd, iopte, *iopte);
566
567	return iopte;
568}
569
570static int iopgd_alloc_section(struct omap_iommu *obj, u32 da, u32 pa, u32 prot)
571{
572	u32 *iopgd = iopgd_offset(obj, da);
573
574	if ((da | pa) & ~IOSECTION_MASK) {
575		dev_err(obj->dev, "%s: %08x:%08x should aligned on %08lx\n",
576			__func__, da, pa, IOSECTION_SIZE);
577		return -EINVAL;
578	}
579
580	*iopgd = (pa & IOSECTION_MASK) | prot | IOPGD_SECTION;
581	flush_iopgd_range(iopgd, iopgd);
582	return 0;
583}
584
585static int iopgd_alloc_super(struct omap_iommu *obj, u32 da, u32 pa, u32 prot)
586{
587	u32 *iopgd = iopgd_offset(obj, da);
588	int i;
589
590	if ((da | pa) & ~IOSUPER_MASK) {
591		dev_err(obj->dev, "%s: %08x:%08x should aligned on %08lx\n",
592			__func__, da, pa, IOSUPER_SIZE);
593		return -EINVAL;
594	}
595
596	for (i = 0; i < 16; i++)
597		*(iopgd + i) = (pa & IOSUPER_MASK) | prot | IOPGD_SUPER;
598	flush_iopgd_range(iopgd, iopgd + 15);
599	return 0;
600}
601
602static int iopte_alloc_page(struct omap_iommu *obj, u32 da, u32 pa, u32 prot)
603{
604	u32 *iopgd = iopgd_offset(obj, da);
605	u32 *iopte = iopte_alloc(obj, iopgd, da);
606
607	if (IS_ERR(iopte))
608		return PTR_ERR(iopte);
609
610	*iopte = (pa & IOPAGE_MASK) | prot | IOPTE_SMALL;
611	flush_iopte_range(iopte, iopte);
612
613	dev_vdbg(obj->dev, "%s: da:%08x pa:%08x pte:%p *pte:%08x\n",
614		 __func__, da, pa, iopte, *iopte);
615
616	return 0;
617}
618
619static int iopte_alloc_large(struct omap_iommu *obj, u32 da, u32 pa, u32 prot)
620{
621	u32 *iopgd = iopgd_offset(obj, da);
622	u32 *iopte = iopte_alloc(obj, iopgd, da);
623	int i;
624
625	if ((da | pa) & ~IOLARGE_MASK) {
626		dev_err(obj->dev, "%s: %08x:%08x should aligned on %08lx\n",
627			__func__, da, pa, IOLARGE_SIZE);
628		return -EINVAL;
629	}
630
631	if (IS_ERR(iopte))
632		return PTR_ERR(iopte);
633
634	for (i = 0; i < 16; i++)
635		*(iopte + i) = (pa & IOLARGE_MASK) | prot | IOPTE_LARGE;
636	flush_iopte_range(iopte, iopte + 15);
637	return 0;
638}
639
640static int
641iopgtable_store_entry_core(struct omap_iommu *obj, struct iotlb_entry *e)
642{
643	int (*fn)(struct omap_iommu *, u32, u32, u32);
644	u32 prot;
645	int err;
646
647	if (!obj || !e)
648		return -EINVAL;
649
650	switch (e->pgsz) {
651	case MMU_CAM_PGSZ_16M:
652		fn = iopgd_alloc_super;
653		break;
654	case MMU_CAM_PGSZ_1M:
655		fn = iopgd_alloc_section;
656		break;
657	case MMU_CAM_PGSZ_64K:
658		fn = iopte_alloc_large;
659		break;
660	case MMU_CAM_PGSZ_4K:
661		fn = iopte_alloc_page;
662		break;
663	default:
664		fn = NULL;
665		BUG();
666		break;
667	}
668
669	prot = get_iopte_attr(e);
670
671	spin_lock(&obj->page_table_lock);
672	err = fn(obj, e->da, e->pa, prot);
673	spin_unlock(&obj->page_table_lock);
674
675	return err;
676}
677
678/**
679 * omap_iopgtable_store_entry - Make an iommu pte entry
680 * @obj:	target iommu
681 * @e:		an iommu tlb entry info
682 **/
683int 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}
693EXPORT_SYMBOL_GPL(omap_iopgtable_store_entry);
694
695/**
696 * iopgtable_lookup_entry - Lookup an iommu pte entry
697 * @obj:	target iommu
698 * @da:		iommu device virtual address
699 * @ppgd:	iommu pgd entry pointer to be returned
700 * @ppte:	iommu pte entry pointer to be returned
701 **/
702static void
703iopgtable_lookup_entry(struct omap_iommu *obj, u32 da, u32 **ppgd, u32 **ppte)
704{
705	u32 *iopgd, *iopte = NULL;
706
707	iopgd = iopgd_offset(obj, da);
708	if (!*iopgd)
709		goto out;
710
711	if (iopgd_is_table(*iopgd))
712		iopte = iopte_offset(iopgd, da);
713out:
714	*ppgd = iopgd;
715	*ppte = iopte;
716}
717
718static size_t iopgtable_clear_entry_core(struct omap_iommu *obj, u32 da)
719{
720	size_t bytes;
721	u32 *iopgd = iopgd_offset(obj, da);
722	int nent = 1;
723
724	if (!*iopgd)
725		return 0;
726
727	if (iopgd_is_table(*iopgd)) {
728		int i;
729		u32 *iopte = iopte_offset(iopgd, da);
730
731		bytes = IOPTE_SIZE;
732		if (*iopte & IOPTE_LARGE) {
733			nent *= 16;
734			/* rewind to the 1st entry */
735			iopte = iopte_offset(iopgd, (da & IOLARGE_MASK));
736		}
737		bytes *= nent;
738		memset(iopte, 0, nent * sizeof(*iopte));
739		flush_iopte_range(iopte, iopte + (nent - 1) * sizeof(*iopte));
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(iopte);
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_iopgd_range(iopgd, iopgd + (nent - 1) * sizeof(*iopgd));
762out:
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 **/
771static 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
785static void iopgtable_clear_entry_all(struct omap_iommu *obj)
786{
787	int i;
788
789	spin_lock(&obj->page_table_lock);
790
791	for (i = 0; i < PTRS_PER_IOPGD; i++) {
792		u32 da;
793		u32 *iopgd;
794
795		da = i << IOPGD_SHIFT;
796		iopgd = iopgd_offset(obj, da);
797
798		if (!*iopgd)
799			continue;
800
801		if (iopgd_is_table(*iopgd))
802			iopte_free(iopte_offset(iopgd, 0));
803
804		*iopgd = 0;
805		flush_iopgd_range(iopgd, iopgd);
806	}
807
808	flush_iotlb_all(obj);
809
810	spin_unlock(&obj->page_table_lock);
811}
812
813/*
814 *	Device IOMMU generic operations
815 */
816static irqreturn_t iommu_fault_handler(int irq, void *data)
817{
818	u32 da, errs;
819	u32 *iopgd, *iopte;
820	struct omap_iommu *obj = data;
821	struct iommu_domain *domain = obj->domain;
822
823	if (!obj->refcount)
824		return IRQ_NONE;
825
826	errs = iommu_report_fault(obj, &da);
827	if (errs == 0)
828		return IRQ_HANDLED;
829
830	/* Fault callback or TLB/PTE Dynamic loading */
831	if (!report_iommu_fault(domain, obj->dev, da, 0))
832		return IRQ_HANDLED;
833
834	iommu_disable(obj);
835
836	iopgd = iopgd_offset(obj, da);
837
838	if (!iopgd_is_table(*iopgd)) {
839		dev_err(obj->dev, "%s: errs:0x%08x da:0x%08x pgd:0x%p *pgd:px%08x\n",
840				obj->name, errs, da, iopgd, *iopgd);
841		return IRQ_NONE;
842	}
843
844	iopte = iopte_offset(iopgd, da);
845
846	dev_err(obj->dev, "%s: errs:0x%08x da:0x%08x pgd:0x%p *pgd:0x%08x pte:0x%p *pte:0x%08x\n",
847			obj->name, errs, da, iopgd, *iopgd, iopte, *iopte);
848
849	return IRQ_NONE;
850}
851
852static int device_match_by_alias(struct device *dev, void *data)
853{
854	struct omap_iommu *obj = to_iommu(dev);
855	const char *name = data;
856
857	pr_debug("%s: %s %s\n", __func__, obj->name, name);
858
859	return strcmp(obj->name, name) == 0;
860}
861
862/**
863 * omap_iommu_attach() - attach iommu device to an iommu domain
864 * @name:	name of target omap iommu device
865 * @iopgd:	page table
866 **/
867static struct omap_iommu *omap_iommu_attach(const char *name, u32 *iopgd)
868{
869	int err;
870	struct device *dev;
871	struct omap_iommu *obj;
872
873	dev = driver_find_device(&omap_iommu_driver.driver, NULL,
874				(void *)name,
875				device_match_by_alias);
876	if (!dev)
877		return ERR_PTR(-ENODEV);
878
879	obj = to_iommu(dev);
880
881	spin_lock(&obj->iommu_lock);
882
883	/* an iommu device can only be attached once */
884	if (++obj->refcount > 1) {
885		dev_err(dev, "%s: already attached!\n", obj->name);
886		err = -EBUSY;
887		goto err_enable;
888	}
889
890	obj->iopgd = iopgd;
891	err = iommu_enable(obj);
892	if (err)
893		goto err_enable;
894	flush_iotlb_all(obj);
895
896	spin_unlock(&obj->iommu_lock);
897
898	dev_dbg(obj->dev, "%s: %s\n", __func__, obj->name);
899	return obj;
900
901err_enable:
902	obj->refcount--;
903	spin_unlock(&obj->iommu_lock);
904	return ERR_PTR(err);
905}
906
907/**
908 * omap_iommu_detach - release iommu device
909 * @obj:	target iommu
910 **/
911static void omap_iommu_detach(struct omap_iommu *obj)
912{
913	if (!obj || IS_ERR(obj))
914		return;
915
916	spin_lock(&obj->iommu_lock);
917
918	if (--obj->refcount == 0)
919		iommu_disable(obj);
920
921	obj->iopgd = NULL;
922
923	spin_unlock(&obj->iommu_lock);
924
925	dev_dbg(obj->dev, "%s: %s\n", __func__, obj->name);
926}
927
928/*
929 *	OMAP Device MMU(IOMMU) detection
930 */
931static int omap_iommu_probe(struct platform_device *pdev)
932{
933	int err = -ENODEV;
934	int irq;
935	struct omap_iommu *obj;
936	struct resource *res;
937	struct iommu_platform_data *pdata = pdev->dev.platform_data;
938	struct device_node *of = pdev->dev.of_node;
939
940	obj = devm_kzalloc(&pdev->dev, sizeof(*obj) + MMU_REG_SIZE, GFP_KERNEL);
941	if (!obj)
942		return -ENOMEM;
943
944	if (of) {
945		obj->name = dev_name(&pdev->dev);
946		obj->nr_tlb_entries = 32;
947		err = of_property_read_u32(of, "ti,#tlb-entries",
948					   &obj->nr_tlb_entries);
949		if (err && err != -EINVAL)
950			return err;
951		if (obj->nr_tlb_entries != 32 && obj->nr_tlb_entries != 8)
952			return -EINVAL;
953		if (of_find_property(of, "ti,iommu-bus-err-back", NULL))
954			obj->has_bus_err_back = MMU_GP_REG_BUS_ERR_BACK_EN;
955	} else {
956		obj->nr_tlb_entries = pdata->nr_tlb_entries;
957		obj->name = pdata->name;
958	}
959
960	obj->dev = &pdev->dev;
961	obj->ctx = (void *)obj + sizeof(*obj);
962
963	spin_lock_init(&obj->iommu_lock);
964	spin_lock_init(&obj->page_table_lock);
965
966	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
967	obj->regbase = devm_ioremap_resource(obj->dev, res);
968	if (IS_ERR(obj->regbase))
969		return PTR_ERR(obj->regbase);
970
971	irq = platform_get_irq(pdev, 0);
972	if (irq < 0)
973		return -ENODEV;
974
975	err = devm_request_irq(obj->dev, irq, iommu_fault_handler, IRQF_SHARED,
976			       dev_name(obj->dev), obj);
977	if (err < 0)
978		return err;
979	platform_set_drvdata(pdev, obj);
980
981	pm_runtime_irq_safe(obj->dev);
982	pm_runtime_enable(obj->dev);
983
984	dev_info(&pdev->dev, "%s registered\n", obj->name);
985	return 0;
986}
987
988static int omap_iommu_remove(struct platform_device *pdev)
989{
990	struct omap_iommu *obj = platform_get_drvdata(pdev);
991
992	iopgtable_clear_entry_all(obj);
993
994	pm_runtime_disable(obj->dev);
995
996	dev_info(&pdev->dev, "%s removed\n", obj->name);
997	return 0;
998}
999
1000static const struct of_device_id omap_iommu_of_match[] = {
1001	{ .compatible = "ti,omap2-iommu" },
1002	{ .compatible = "ti,omap4-iommu" },
1003	{ .compatible = "ti,dra7-iommu"	},
1004	{},
1005};
1006MODULE_DEVICE_TABLE(of, omap_iommu_of_match);
1007
1008static struct platform_driver omap_iommu_driver = {
1009	.probe	= omap_iommu_probe,
1010	.remove	= omap_iommu_remove,
1011	.driver	= {
1012		.name	= "omap-iommu",
1013		.of_match_table = of_match_ptr(omap_iommu_of_match),
1014	},
1015};
1016
1017static void iopte_cachep_ctor(void *iopte)
1018{
1019	clean_dcache_area(iopte, IOPTE_TABLE_SIZE);
1020}
1021
1022static u32 iotlb_init_entry(struct iotlb_entry *e, u32 da, u32 pa, int pgsz)
1023{
1024	memset(e, 0, sizeof(*e));
1025
1026	e->da		= da;
1027	e->pa		= pa;
1028	e->valid	= MMU_CAM_V;
1029	/* FIXME: add OMAP1 support */
1030	e->pgsz		= pgsz;
1031	e->endian	= MMU_RAM_ENDIAN_LITTLE;
1032	e->elsz		= MMU_RAM_ELSZ_8;
1033	e->mixed	= 0;
1034
1035	return iopgsz_to_bytes(e->pgsz);
1036}
1037
1038static int omap_iommu_map(struct iommu_domain *domain, unsigned long da,
1039			 phys_addr_t pa, size_t bytes, int prot)
1040{
1041	struct omap_iommu_domain *omap_domain = domain->priv;
1042	struct omap_iommu *oiommu = omap_domain->iommu_dev;
1043	struct device *dev = oiommu->dev;
1044	struct iotlb_entry e;
1045	int omap_pgsz;
1046	u32 ret;
1047
1048	omap_pgsz = bytes_to_iopgsz(bytes);
1049	if (omap_pgsz < 0) {
1050		dev_err(dev, "invalid size to map: %d\n", bytes);
1051		return -EINVAL;
1052	}
1053
1054	dev_dbg(dev, "mapping da 0x%lx to pa 0x%x size 0x%x\n", da, pa, bytes);
1055
1056	iotlb_init_entry(&e, da, pa, omap_pgsz);
1057
1058	ret = omap_iopgtable_store_entry(oiommu, &e);
1059	if (ret)
1060		dev_err(dev, "omap_iopgtable_store_entry failed: %d\n", ret);
1061
1062	return ret;
1063}
1064
1065static size_t omap_iommu_unmap(struct iommu_domain *domain, unsigned long da,
1066			    size_t size)
1067{
1068	struct omap_iommu_domain *omap_domain = domain->priv;
1069	struct omap_iommu *oiommu = omap_domain->iommu_dev;
1070	struct device *dev = oiommu->dev;
1071
1072	dev_dbg(dev, "unmapping da 0x%lx size %u\n", da, size);
1073
1074	return iopgtable_clear_entry(oiommu, da);
1075}
1076
1077static int
1078omap_iommu_attach_dev(struct iommu_domain *domain, struct device *dev)
1079{
1080	struct omap_iommu_domain *omap_domain = domain->priv;
1081	struct omap_iommu *oiommu;
1082	struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
1083	int ret = 0;
1084
1085	if (!arch_data || !arch_data->name) {
1086		dev_err(dev, "device doesn't have an associated iommu\n");
1087		return -EINVAL;
1088	}
1089
1090	spin_lock(&omap_domain->lock);
1091
1092	/* only a single device is supported per domain for now */
1093	if (omap_domain->iommu_dev) {
1094		dev_err(dev, "iommu domain is already attached\n");
1095		ret = -EBUSY;
1096		goto out;
1097	}
1098
1099	/* get a handle to and enable the omap iommu */
1100	oiommu = omap_iommu_attach(arch_data->name, omap_domain->pgtable);
1101	if (IS_ERR(oiommu)) {
1102		ret = PTR_ERR(oiommu);
1103		dev_err(dev, "can't get omap iommu: %d\n", ret);
1104		goto out;
1105	}
1106
1107	omap_domain->iommu_dev = arch_data->iommu_dev = oiommu;
1108	omap_domain->dev = dev;
1109	oiommu->domain = domain;
1110
1111out:
1112	spin_unlock(&omap_domain->lock);
1113	return ret;
1114}
1115
1116static void _omap_iommu_detach_dev(struct omap_iommu_domain *omap_domain,
1117			struct device *dev)
1118{
1119	struct omap_iommu *oiommu = dev_to_omap_iommu(dev);
1120	struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
1121
1122	/* only a single device is supported per domain for now */
1123	if (omap_domain->iommu_dev != oiommu) {
1124		dev_err(dev, "invalid iommu device\n");
1125		return;
1126	}
1127
1128	iopgtable_clear_entry_all(oiommu);
1129
1130	omap_iommu_detach(oiommu);
1131
1132	omap_domain->iommu_dev = arch_data->iommu_dev = NULL;
1133	omap_domain->dev = NULL;
1134}
1135
1136static void omap_iommu_detach_dev(struct iommu_domain *domain,
1137				 struct device *dev)
1138{
1139	struct omap_iommu_domain *omap_domain = domain->priv;
1140
1141	spin_lock(&omap_domain->lock);
1142	_omap_iommu_detach_dev(omap_domain, dev);
1143	spin_unlock(&omap_domain->lock);
1144}
1145
1146static int omap_iommu_domain_init(struct iommu_domain *domain)
1147{
1148	struct omap_iommu_domain *omap_domain;
1149
1150	omap_domain = kzalloc(sizeof(*omap_domain), GFP_KERNEL);
1151	if (!omap_domain) {
1152		pr_err("kzalloc failed\n");
1153		goto out;
1154	}
1155
1156	omap_domain->pgtable = kzalloc(IOPGD_TABLE_SIZE, GFP_KERNEL);
1157	if (!omap_domain->pgtable) {
1158		pr_err("kzalloc failed\n");
1159		goto fail_nomem;
1160	}
1161
1162	/*
1163	 * should never fail, but please keep this around to ensure
1164	 * we keep the hardware happy
1165	 */
1166	BUG_ON(!IS_ALIGNED((long)omap_domain->pgtable, IOPGD_TABLE_SIZE));
1167
1168	clean_dcache_area(omap_domain->pgtable, IOPGD_TABLE_SIZE);
1169	spin_lock_init(&omap_domain->lock);
1170
1171	domain->priv = omap_domain;
1172
1173	domain->geometry.aperture_start = 0;
1174	domain->geometry.aperture_end   = (1ULL << 32) - 1;
1175	domain->geometry.force_aperture = true;
1176
1177	return 0;
1178
1179fail_nomem:
1180	kfree(omap_domain);
1181out:
1182	return -ENOMEM;
1183}
1184
1185static void omap_iommu_domain_destroy(struct iommu_domain *domain)
1186{
1187	struct omap_iommu_domain *omap_domain = domain->priv;
1188
1189	domain->priv = NULL;
1190
1191	/*
1192	 * An iommu device is still attached
1193	 * (currently, only one device can be attached) ?
1194	 */
1195	if (omap_domain->iommu_dev)
1196		_omap_iommu_detach_dev(omap_domain, omap_domain->dev);
1197
1198	kfree(omap_domain->pgtable);
1199	kfree(omap_domain);
1200}
1201
1202static phys_addr_t omap_iommu_iova_to_phys(struct iommu_domain *domain,
1203					  dma_addr_t da)
1204{
1205	struct omap_iommu_domain *omap_domain = domain->priv;
1206	struct omap_iommu *oiommu = omap_domain->iommu_dev;
1207	struct device *dev = oiommu->dev;
1208	u32 *pgd, *pte;
1209	phys_addr_t ret = 0;
1210
1211	iopgtable_lookup_entry(oiommu, da, &pgd, &pte);
1212
1213	if (pte) {
1214		if (iopte_is_small(*pte))
1215			ret = omap_iommu_translate(*pte, da, IOPTE_MASK);
1216		else if (iopte_is_large(*pte))
1217			ret = omap_iommu_translate(*pte, da, IOLARGE_MASK);
1218		else
1219			dev_err(dev, "bogus pte 0x%x, da 0x%llx", *pte,
1220							(unsigned long long)da);
1221	} else {
1222		if (iopgd_is_section(*pgd))
1223			ret = omap_iommu_translate(*pgd, da, IOSECTION_MASK);
1224		else if (iopgd_is_super(*pgd))
1225			ret = omap_iommu_translate(*pgd, da, IOSUPER_MASK);
1226		else
1227			dev_err(dev, "bogus pgd 0x%x, da 0x%llx", *pgd,
1228							(unsigned long long)da);
1229	}
1230
1231	return ret;
1232}
1233
1234static int omap_iommu_add_device(struct device *dev)
1235{
1236	struct omap_iommu_arch_data *arch_data;
1237	struct device_node *np;
1238	struct platform_device *pdev;
1239
1240	/*
1241	 * Allocate the archdata iommu structure for DT-based devices.
1242	 *
1243	 * TODO: Simplify this when removing non-DT support completely from the
1244	 * IOMMU users.
1245	 */
1246	if (!dev->of_node)
1247		return 0;
1248
1249	np = of_parse_phandle(dev->of_node, "iommus", 0);
1250	if (!np)
1251		return 0;
1252
1253	pdev = of_find_device_by_node(np);
1254	if (WARN_ON(!pdev)) {
1255		of_node_put(np);
1256		return -EINVAL;
1257	}
1258
1259	arch_data = kzalloc(sizeof(*arch_data), GFP_KERNEL);
1260	if (!arch_data) {
1261		of_node_put(np);
1262		return -ENOMEM;
1263	}
1264
1265	arch_data->name = kstrdup(dev_name(&pdev->dev), GFP_KERNEL);
1266	dev->archdata.iommu = arch_data;
1267
1268	of_node_put(np);
1269
1270	return 0;
1271}
1272
1273static void omap_iommu_remove_device(struct device *dev)
1274{
1275	struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
1276
1277	if (!dev->of_node || !arch_data)
1278		return;
1279
1280	kfree(arch_data->name);
1281	kfree(arch_data);
1282}
1283
1284static const struct iommu_ops omap_iommu_ops = {
1285	.domain_init	= omap_iommu_domain_init,
1286	.domain_destroy	= omap_iommu_domain_destroy,
1287	.attach_dev	= omap_iommu_attach_dev,
1288	.detach_dev	= omap_iommu_detach_dev,
1289	.map		= omap_iommu_map,
1290	.unmap		= omap_iommu_unmap,
1291	.iova_to_phys	= omap_iommu_iova_to_phys,
1292	.add_device	= omap_iommu_add_device,
1293	.remove_device	= omap_iommu_remove_device,
1294	.pgsize_bitmap	= OMAP_IOMMU_PGSIZES,
1295};
1296
1297static int __init omap_iommu_init(void)
1298{
1299	struct kmem_cache *p;
1300	const unsigned long flags = SLAB_HWCACHE_ALIGN;
1301	size_t align = 1 << 10; /* L2 pagetable alignement */
1302
1303	p = kmem_cache_create("iopte_cache", IOPTE_TABLE_SIZE, align, flags,
1304			      iopte_cachep_ctor);
1305	if (!p)
1306		return -ENOMEM;
1307	iopte_cachep = p;
1308
1309	bus_set_iommu(&platform_bus_type, &omap_iommu_ops);
1310
1311	return platform_driver_register(&omap_iommu_driver);
1312}
1313/* must be ready before omap3isp is probed */
1314subsys_initcall(omap_iommu_init);
1315
1316static void __exit omap_iommu_exit(void)
1317{
1318	kmem_cache_destroy(iopte_cachep);
1319
1320	platform_driver_unregister(&omap_iommu_driver);
1321}
1322module_exit(omap_iommu_exit);
1323
1324MODULE_DESCRIPTION("omap iommu: tlb and pagetable primitives");
1325MODULE_ALIAS("platform:omap-iommu");
1326MODULE_AUTHOR("Hiroshi DOYU, Paul Mundt and Toshihiro Kobayashi");
1327MODULE_LICENSE("GPL v2");
1328