drivers/iommu/shmobile-iommu.c - linux - Git at Google

 /*
  * IOMMU for IPMMU/IPMMUI
  * Copyright (C) 2012  Hideki EIRAKU
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; version 2 of the License.
  */

 #include <linux/dma-mapping.h>
 #include <linux/io.h>
 #include <linux/iommu.h>
 #include <linux/platform_device.h>
 #include <linux/sizes.h>
 #include <linux/slab.h>
 #include <asm/dma-iommu.h>
 #include "shmobile-ipmmu.h"

 #define L1_SIZE CONFIG_SHMOBILE_IOMMU_L1SIZE
 #define L1_LEN (L1_SIZE / 4)
 #define L1_ALIGN L1_SIZE
 #define L2_SIZE SZ_1K
 #define L2_LEN (L2_SIZE / 4)
 #define L2_ALIGN L2_SIZE

 struct shmobile_iommu_domain_pgtable {
 	uint32_t *pgtable;
 	dma_addr_t handle;
 };

 struct shmobile_iommu_archdata {
 	struct list_head attached_list;
 	struct dma_iommu_mapping *iommu_mapping;
 	spinlock_t attach_lock;
 	struct shmobile_iommu_domain *attached;
 	int num_attached_devices;
 	struct shmobile_ipmmu *ipmmu;
 };

 struct shmobile_iommu_domain {
 	struct shmobile_iommu_domain_pgtable l1, l2[L1_LEN];
 	spinlock_t map_lock;
 	spinlock_t attached_list_lock;
 	struct list_head attached_list;
 };

 static struct shmobile_iommu_archdata *ipmmu_archdata;
 static struct kmem_cache *l1cache, *l2cache;

 static int pgtable_alloc(struct shmobile_iommu_domain_pgtable *pgtable,
 			 struct kmem_cache *cache, size_t size)
 {
 	pgtable->pgtable = kmem_cache_zalloc(cache, GFP_ATOMIC);
 	if (!pgtable->pgtable)
 		return -ENOMEM;
 	pgtable->handle = dma_map_single(NULL, pgtable->pgtable, size,
 					 DMA_TO_DEVICE);
 	return 0;
 }

 static void pgtable_free(struct shmobile_iommu_domain_pgtable *pgtable,
 			 struct kmem_cache *cache, size_t size)
 {
 	dma_unmap_single(NULL, pgtable->handle, size, DMA_TO_DEVICE);
 	kmem_cache_free(cache, pgtable->pgtable);
 }

 static uint32_t pgtable_read(struct shmobile_iommu_domain_pgtable *pgtable,
 			     unsigned int index)
 {
 	return pgtable->pgtable[index];
 }

 static void pgtable_write(struct shmobile_iommu_domain_pgtable *pgtable,
 			  unsigned int index, unsigned int count, uint32_t val)
 {
 	unsigned int i;

 	for (i = 0; i < count; i++)
 		pgtable->pgtable[index + i] = val;
 	dma_sync_single_for_device(NULL, pgtable->handle + index * sizeof(val),
 				   sizeof(val) * count, DMA_TO_DEVICE);
 }

 static int shmobile_iommu_domain_init(struct iommu_domain *domain)
 {
 	struct shmobile_iommu_domain *sh_domain;
 	int i, ret;

 	sh_domain = kmalloc(sizeof(*sh_domain), GFP_KERNEL);
 	if (!sh_domain)
 		return -ENOMEM;
 	ret = pgtable_alloc(&sh_domain->l1, l1cache, L1_SIZE);
 	if (ret < 0) {
 		kfree(sh_domain);
 		return ret;
 	}
 	for (i = 0; i < L1_LEN; i++)
 		sh_domain->l2[i].pgtable = NULL;
 	spin_lock_init(&sh_domain->map_lock);
 	spin_lock_init(&sh_domain->attached_list_lock);
 	INIT_LIST_HEAD(&sh_domain->attached_list);
 	domain->priv = sh_domain;
 	return 0;
 }

 static void shmobile_iommu_domain_destroy(struct iommu_domain *domain)
 {
 	struct shmobile_iommu_domain *sh_domain = domain->priv;
 	int i;

 	for (i = 0; i < L1_LEN; i++) {
 		if (sh_domain->l2[i].pgtable)
 			pgtable_free(&sh_domain->l2[i], l2cache, L2_SIZE);
 	}
 	pgtable_free(&sh_domain->l1, l1cache, L1_SIZE);
 	kfree(sh_domain);
 	domain->priv = NULL;
 }

 static int shmobile_iommu_attach_device(struct iommu_domain *domain,
 					struct device *dev)
 {
 	struct shmobile_iommu_archdata *archdata = dev->archdata.iommu;
 	struct shmobile_iommu_domain *sh_domain = domain->priv;
 	int ret = -EBUSY;

 	if (!archdata)
 		return -ENODEV;
 	spin_lock(&sh_domain->attached_list_lock);
 	spin_lock(&archdata->attach_lock);
 	if (archdata->attached != sh_domain) {
 		if (archdata->attached)
 			goto err;
 		ipmmu_tlb_set(archdata->ipmmu, sh_domain->l1.handle, L1_SIZE,
 			      0);
 		ipmmu_tlb_flush(archdata->ipmmu);
 		archdata->attached = sh_domain;
 		archdata->num_attached_devices = 0;
 		list_add(&archdata->attached_list, &sh_domain->attached_list);
 	}
 	archdata->num_attached_devices++;
 	ret = 0;
 err:
 	spin_unlock(&archdata->attach_lock);
 	spin_unlock(&sh_domain->attached_list_lock);
 	return ret;
 }

 static void shmobile_iommu_detach_device(struct iommu_domain *domain,
 					 struct device *dev)
 {
 	struct shmobile_iommu_archdata *archdata = dev->archdata.iommu;
 	struct shmobile_iommu_domain *sh_domain = domain->priv;

 	if (!archdata)
 		return;
 	spin_lock(&sh_domain->attached_list_lock);
 	spin_lock(&archdata->attach_lock);
 	archdata->num_attached_devices--;
 	if (!archdata->num_attached_devices) {
 		ipmmu_tlb_set(archdata->ipmmu, 0, 0, 0);
 		ipmmu_tlb_flush(archdata->ipmmu);
 		archdata->attached = NULL;
 		list_del(&archdata->attached_list);
 	}
 	spin_unlock(&archdata->attach_lock);
 	spin_unlock(&sh_domain->attached_list_lock);
 }

 static void domain_tlb_flush(struct shmobile_iommu_domain *sh_domain)
 {
 	struct shmobile_iommu_archdata *archdata;

 	spin_lock(&sh_domain->attached_list_lock);
 	list_for_each_entry(archdata, &sh_domain->attached_list, attached_list)
 		ipmmu_tlb_flush(archdata->ipmmu);
 	spin_unlock(&sh_domain->attached_list_lock);
 }

 static int l2alloc(struct shmobile_iommu_domain *sh_domain,
 		   unsigned int l1index)
 {
 	int ret;

 	if (!sh_domain->l2[l1index].pgtable) {
 		ret = pgtable_alloc(&sh_domain->l2[l1index], l2cache, L2_SIZE);
 		if (ret < 0)
 			return ret;
 	}
 	pgtable_write(&sh_domain->l1, l1index, 1,
 		      sh_domain->l2[l1index].handle | 0x1);
 	return 0;
 }

 static void l2realfree(struct shmobile_iommu_domain_pgtable *l2)
 {
 	if (l2->pgtable)
 		pgtable_free(l2, l2cache, L2_SIZE);
 }

 static void l2free(struct shmobile_iommu_domain *sh_domain,
 		   unsigned int l1index,
 		   struct shmobile_iommu_domain_pgtable *l2)
 {
 	pgtable_write(&sh_domain->l1, l1index, 1, 0);
 	if (sh_domain->l2[l1index].pgtable) {
 		*l2 = sh_domain->l2[l1index];
 		sh_domain->l2[l1index].pgtable = NULL;
 	}
 }

 static int shmobile_iommu_map(struct iommu_domain *domain, unsigned long iova,
 			      phys_addr_t paddr, size_t size, int prot)
 {
 	struct shmobile_iommu_domain_pgtable l2 = { .pgtable = NULL };
 	struct shmobile_iommu_domain *sh_domain = domain->priv;
 	unsigned int l1index, l2index;
 	int ret;

 	l1index = iova >> 20;
 	switch (size) {
 	case SZ_4K:
 		l2index = (iova >> 12) & 0xff;
 		spin_lock(&sh_domain->map_lock);
 		ret = l2alloc(sh_domain, l1index);
 		if (!ret)
 			pgtable_write(&sh_domain->l2[l1index], l2index, 1,
 				      paddr | 0xff2);
 		spin_unlock(&sh_domain->map_lock);
 		break;
 	case SZ_64K:
 		l2index = (iova >> 12) & 0xf0;
 		spin_lock(&sh_domain->map_lock);
 		ret = l2alloc(sh_domain, l1index);
 		if (!ret)
 			pgtable_write(&sh_domain->l2[l1index], l2index, 0x10,
 				      paddr | 0xff1);
 		spin_unlock(&sh_domain->map_lock);
 		break;
 	case SZ_1M:
 		spin_lock(&sh_domain->map_lock);
 		l2free(sh_domain, l1index, &l2);
 		pgtable_write(&sh_domain->l1, l1index, 1, paddr | 0xc02);
 		spin_unlock(&sh_domain->map_lock);
 		ret = 0;
 		break;
 	default:
 		ret = -EINVAL;
 	}
 	if (!ret)
 		domain_tlb_flush(sh_domain);
 	l2realfree(&l2);
 	return ret;
 }

 static size_t shmobile_iommu_unmap(struct iommu_domain *domain,
 				   unsigned long iova, size_t size)
 {
 	struct shmobile_iommu_domain_pgtable l2 = { .pgtable = NULL };
 	struct shmobile_iommu_domain *sh_domain = domain->priv;
 	unsigned int l1index, l2index;
 	uint32_t l2entry = 0;
 	size_t ret = 0;

 	l1index = iova >> 20;
 	if (!(iova & 0xfffff) && size >= SZ_1M) {
 		spin_lock(&sh_domain->map_lock);
 		l2free(sh_domain, l1index, &l2);
 		spin_unlock(&sh_domain->map_lock);
 		ret = SZ_1M;
 		goto done;
 	}
 	l2index = (iova >> 12) & 0xff;
 	spin_lock(&sh_domain->map_lock);
 	if (sh_domain->l2[l1index].pgtable)
 		l2entry = pgtable_read(&sh_domain->l2[l1index], l2index);
 	switch (l2entry & 3) {
 	case 1:
 		if (l2index & 0xf)
 			break;
 		pgtable_write(&sh_domain->l2[l1index], l2index, 0x10, 0);
 		ret = SZ_64K;
 		break;
 	case 2:
 		pgtable_write(&sh_domain->l2[l1index], l2index, 1, 0);
 		ret = SZ_4K;
 		break;
 	}
 	spin_unlock(&sh_domain->map_lock);
 done:
 	if (ret)
 		domain_tlb_flush(sh_domain);
 	l2realfree(&l2);
 	return ret;
 }

 static phys_addr_t shmobile_iommu_iova_to_phys(struct iommu_domain *domain,
 					       dma_addr_t iova)
 {
 	struct shmobile_iommu_domain *sh_domain = domain->priv;
 	uint32_t l1entry = 0, l2entry = 0;
 	unsigned int l1index, l2index;

 	l1index = iova >> 20;
 	l2index = (iova >> 12) & 0xff;
 	spin_lock(&sh_domain->map_lock);
 	if (sh_domain->l2[l1index].pgtable)
 		l2entry = pgtable_read(&sh_domain->l2[l1index], l2index);
 	else
 		l1entry = pgtable_read(&sh_domain->l1, l1index);
 	spin_unlock(&sh_domain->map_lock);
 	switch (l2entry & 3) {
 	case 1:
 		return (l2entry & ~0xffff) | (iova & 0xffff);
 	case 2:
 		return (l2entry & ~0xfff) | (iova & 0xfff);
 	default:
 		if ((l1entry & 3) == 2)
 			return (l1entry & ~0xfffff) | (iova & 0xfffff);
 		return 0;
 	}
 }

 static int find_dev_name(struct shmobile_ipmmu *ipmmu, const char *dev_name)
 {
 	unsigned int i, n = ipmmu->num_dev_names;

 	for (i = 0; i < n; i++) {
 		if (strcmp(ipmmu->dev_names[i], dev_name) == 0)
 			return 1;
 	}
 	return 0;
 }

 static int shmobile_iommu_add_device(struct device *dev)
 {
 	struct shmobile_iommu_archdata *archdata = ipmmu_archdata;
 	struct dma_iommu_mapping *mapping;

 	if (!find_dev_name(archdata->ipmmu, dev_name(dev)))
 		return 0;
 	mapping = archdata->iommu_mapping;
 	if (!mapping) {
 		mapping = arm_iommu_create_mapping(&platform_bus_type, 0,
 						   L1_LEN << 20);
 		if (IS_ERR(mapping))
 			return PTR_ERR(mapping);
 		archdata->iommu_mapping = mapping;
 	}
 	dev->archdata.iommu = archdata;
 	if (arm_iommu_attach_device(dev, mapping))
 		pr_err("arm_iommu_attach_device failed\n");
 	return 0;
 }

 static const struct iommu_ops shmobile_iommu_ops = {
 	.domain_init = shmobile_iommu_domain_init,
 	.domain_destroy = shmobile_iommu_domain_destroy,
 	.attach_dev = shmobile_iommu_attach_device,
 	.detach_dev = shmobile_iommu_detach_device,
 	.map = shmobile_iommu_map,
 	.unmap = shmobile_iommu_unmap,
 	.map_sg = default_iommu_map_sg,
 	.iova_to_phys = shmobile_iommu_iova_to_phys,
 	.add_device = shmobile_iommu_add_device,
 	.pgsize_bitmap = SZ_1M | SZ_64K | SZ_4K,
 };

 int ipmmu_iommu_init(struct shmobile_ipmmu *ipmmu)
 {
 	static struct shmobile_iommu_archdata *archdata;

 	l1cache = kmem_cache_create("shmobile-iommu-pgtable1", L1_SIZE,
 				    L1_ALIGN, SLAB_HWCACHE_ALIGN, NULL);
 	if (!l1cache)
 		return -ENOMEM;
 	l2cache = kmem_cache_create("shmobile-iommu-pgtable2", L2_SIZE,
 				    L2_ALIGN, SLAB_HWCACHE_ALIGN, NULL);
 	if (!l2cache) {
 		kmem_cache_destroy(l1cache);
 		return -ENOMEM;
 	}
 	archdata = kzalloc(sizeof(*archdata), GFP_KERNEL);
 	if (!archdata) {
 		kmem_cache_destroy(l1cache);
 		kmem_cache_destroy(l2cache);
 		return -ENOMEM;
 	}
 	spin_lock_init(&archdata->attach_lock);
 	archdata->ipmmu = ipmmu;
 	ipmmu_archdata = archdata;
 	bus_set_iommu(&platform_bus_type, &shmobile_iommu_ops);
 	return 0;
 }
	/*
	* IOMMU for IPMMU/IPMMUI
	* Copyright (C) 2012 Hideki EIRAKU
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; version 2 of the License.
	*/

	#include <linux/dma-mapping.h>
	#include <linux/io.h>
	#include <linux/iommu.h>
	#include <linux/platform_device.h>
	#include <linux/sizes.h>
	#include <linux/slab.h>
	#include <asm/dma-iommu.h>
	#include "shmobile-ipmmu.h"

	#define L1_SIZE CONFIG_SHMOBILE_IOMMU_L1SIZE
	#define L1_LEN (L1_SIZE / 4)
	#define L1_ALIGN L1_SIZE
	#define L2_SIZE SZ_1K
	#define L2_LEN (L2_SIZE / 4)
	#define L2_ALIGN L2_SIZE

	struct shmobile_iommu_domain_pgtable {
	uint32_t *pgtable;
	dma_addr_t handle;
	};

	struct shmobile_iommu_archdata {
	struct list_head attached_list;
	struct dma_iommu_mapping *iommu_mapping;
	spinlock_t attach_lock;
	struct shmobile_iommu_domain *attached;
	int num_attached_devices;
	struct shmobile_ipmmu *ipmmu;
	};

	struct shmobile_iommu_domain {
	struct shmobile_iommu_domain_pgtable l1, l2[L1_LEN];
	spinlock_t map_lock;
	spinlock_t attached_list_lock;
	struct list_head attached_list;
	};

	static struct shmobile_iommu_archdata *ipmmu_archdata;
	static struct kmem_cache l1cache, l2cache;

	static int pgtable_alloc(struct shmobile_iommu_domain_pgtable *pgtable,
	struct kmem_cache *cache, size_t size)
	{
	pgtable->pgtable = kmem_cache_zalloc(cache, GFP_ATOMIC);
	if (!pgtable->pgtable)
	return -ENOMEM;
	pgtable->handle = dma_map_single(NULL, pgtable->pgtable, size,
	DMA_TO_DEVICE);
	return 0;
	}

	static void pgtable_free(struct shmobile_iommu_domain_pgtable *pgtable,
	struct kmem_cache *cache, size_t size)
	{
	dma_unmap_single(NULL, pgtable->handle, size, DMA_TO_DEVICE);
	kmem_cache_free(cache, pgtable->pgtable);
	}

	static uint32_t pgtable_read(struct shmobile_iommu_domain_pgtable *pgtable,
	unsigned int index)
	{
	return pgtable->pgtable[index];
	}

	static void pgtable_write(struct shmobile_iommu_domain_pgtable *pgtable,
	unsigned int index, unsigned int count, uint32_t val)
	{
	unsigned int i;

	for (i = 0; i < count; i++)
	pgtable->pgtable[index + i] = val;
	dma_sync_single_for_device(NULL, pgtable->handle + index * sizeof(val),
	sizeof(val) * count, DMA_TO_DEVICE);
	}

	static int shmobile_iommu_domain_init(struct iommu_domain *domain)
	{
	struct shmobile_iommu_domain *sh_domain;
	int i, ret;

	sh_domain = kmalloc(sizeof(*sh_domain), GFP_KERNEL);
	if (!sh_domain)
	return -ENOMEM;
	ret = pgtable_alloc(&sh_domain->l1, l1cache, L1_SIZE);
	if (ret < 0) {
	kfree(sh_domain);
	return ret;
	}
	for (i = 0; i < L1_LEN; i++)
	sh_domain->l2[i].pgtable = NULL;
	spin_lock_init(&sh_domain->map_lock);
	spin_lock_init(&sh_domain->attached_list_lock);
	INIT_LIST_HEAD(&sh_domain->attached_list);
	domain->priv = sh_domain;
	return 0;
	}

	static void shmobile_iommu_domain_destroy(struct iommu_domain *domain)
	{
	struct shmobile_iommu_domain *sh_domain = domain->priv;
	int i;

	for (i = 0; i < L1_LEN; i++) {
	if (sh_domain->l2[i].pgtable)
	pgtable_free(&sh_domain->l2[i], l2cache, L2_SIZE);
	}
	pgtable_free(&sh_domain->l1, l1cache, L1_SIZE);
	kfree(sh_domain);
	domain->priv = NULL;
	}

	static int shmobile_iommu_attach_device(struct iommu_domain *domain,
	struct device *dev)
	{
	struct shmobile_iommu_archdata *archdata = dev->archdata.iommu;
	struct shmobile_iommu_domain *sh_domain = domain->priv;
	int ret = -EBUSY;

	if (!archdata)
	return -ENODEV;
	spin_lock(&sh_domain->attached_list_lock);
	spin_lock(&archdata->attach_lock);
	if (archdata->attached != sh_domain) {
	if (archdata->attached)
	goto err;
	ipmmu_tlb_set(archdata->ipmmu, sh_domain->l1.handle, L1_SIZE,
	0);
	ipmmu_tlb_flush(archdata->ipmmu);
	archdata->attached = sh_domain;
	archdata->num_attached_devices = 0;
	list_add(&archdata->attached_list, &sh_domain->attached_list);
	}
	archdata->num_attached_devices++;
	ret = 0;
	err:
	spin_unlock(&archdata->attach_lock);
	spin_unlock(&sh_domain->attached_list_lock);
	return ret;
	}

	static void shmobile_iommu_detach_device(struct iommu_domain *domain,
	struct device *dev)
	{
	struct shmobile_iommu_archdata *archdata = dev->archdata.iommu;
	struct shmobile_iommu_domain *sh_domain = domain->priv;

	if (!archdata)
	return;
	spin_lock(&sh_domain->attached_list_lock);
	spin_lock(&archdata->attach_lock);
	archdata->num_attached_devices--;
	if (!archdata->num_attached_devices) {
	ipmmu_tlb_set(archdata->ipmmu, 0, 0, 0);
	ipmmu_tlb_flush(archdata->ipmmu);
	archdata->attached = NULL;
	list_del(&archdata->attached_list);
	}
	spin_unlock(&archdata->attach_lock);
	spin_unlock(&sh_domain->attached_list_lock);
	}

	static void domain_tlb_flush(struct shmobile_iommu_domain *sh_domain)
	{
	struct shmobile_iommu_archdata *archdata;

	spin_lock(&sh_domain->attached_list_lock);
	list_for_each_entry(archdata, &sh_domain->attached_list, attached_list)
	ipmmu_tlb_flush(archdata->ipmmu);
	spin_unlock(&sh_domain->attached_list_lock);
	}

	static int l2alloc(struct shmobile_iommu_domain *sh_domain,
	unsigned int l1index)
	{
	int ret;

	if (!sh_domain->l2[l1index].pgtable) {
	ret = pgtable_alloc(&sh_domain->l2[l1index], l2cache, L2_SIZE);
	if (ret < 0)
	return ret;
	}
	pgtable_write(&sh_domain->l1, l1index, 1,
	sh_domain->l2[l1index].handle \| 0x1);
	return 0;
	}

	static void l2realfree(struct shmobile_iommu_domain_pgtable *l2)
	{
	if (l2->pgtable)
	pgtable_free(l2, l2cache, L2_SIZE);
	}

	static void l2free(struct shmobile_iommu_domain *sh_domain,
	unsigned int l1index,
	struct shmobile_iommu_domain_pgtable *l2)
	{
	pgtable_write(&sh_domain->l1, l1index, 1, 0);
	if (sh_domain->l2[l1index].pgtable) {
	*l2 = sh_domain->l2[l1index];
	sh_domain->l2[l1index].pgtable = NULL;
	}
	}

	static int shmobile_iommu_map(struct iommu_domain *domain, unsigned long iova,
	phys_addr_t paddr, size_t size, int prot)
	{
	struct shmobile_iommu_domain_pgtable l2 = { .pgtable = NULL };
	struct shmobile_iommu_domain *sh_domain = domain->priv;
	unsigned int l1index, l2index;
	int ret;

	l1index = iova >> 20;
	switch (size) {
	case SZ_4K:
	l2index = (iova >> 12) & 0xff;
	spin_lock(&sh_domain->map_lock);
	ret = l2alloc(sh_domain, l1index);
	if (!ret)
	pgtable_write(&sh_domain->l2[l1index], l2index, 1,
	paddr \| 0xff2);
	spin_unlock(&sh_domain->map_lock);
	break;
	case SZ_64K:
	l2index = (iova >> 12) & 0xf0;
	spin_lock(&sh_domain->map_lock);
	ret = l2alloc(sh_domain, l1index);
	if (!ret)
	pgtable_write(&sh_domain->l2[l1index], l2index, 0x10,
	paddr \| 0xff1);
	spin_unlock(&sh_domain->map_lock);
	break;
	case SZ_1M:
	spin_lock(&sh_domain->map_lock);
	l2free(sh_domain, l1index, &l2);
	pgtable_write(&sh_domain->l1, l1index, 1, paddr \| 0xc02);
	spin_unlock(&sh_domain->map_lock);
	ret = 0;
	break;
	default:
	ret = -EINVAL;
	}
	if (!ret)
	domain_tlb_flush(sh_domain);
	l2realfree(&l2);
	return ret;
	}

	static size_t shmobile_iommu_unmap(struct iommu_domain *domain,
	unsigned long iova, size_t size)
	{
	struct shmobile_iommu_domain_pgtable l2 = { .pgtable = NULL };
	struct shmobile_iommu_domain *sh_domain = domain->priv;
	unsigned int l1index, l2index;
	uint32_t l2entry = 0;
	size_t ret = 0;

	l1index = iova >> 20;
	if (!(iova & 0xfffff) && size >= SZ_1M) {
	spin_lock(&sh_domain->map_lock);
	l2free(sh_domain, l1index, &l2);
	spin_unlock(&sh_domain->map_lock);
	ret = SZ_1M;
	goto done;
	}
	l2index = (iova >> 12) & 0xff;
	spin_lock(&sh_domain->map_lock);
	if (sh_domain->l2[l1index].pgtable)
	l2entry = pgtable_read(&sh_domain->l2[l1index], l2index);
	switch (l2entry & 3) {
	case 1:
	if (l2index & 0xf)
	break;
	pgtable_write(&sh_domain->l2[l1index], l2index, 0x10, 0);
	ret = SZ_64K;
	break;
	case 2:
	pgtable_write(&sh_domain->l2[l1index], l2index, 1, 0);
	ret = SZ_4K;
	break;
	}
	spin_unlock(&sh_domain->map_lock);
	done:
	if (ret)
	domain_tlb_flush(sh_domain);
	l2realfree(&l2);
	return ret;
	}

	static phys_addr_t shmobile_iommu_iova_to_phys(struct iommu_domain *domain,
	dma_addr_t iova)
	{
	struct shmobile_iommu_domain *sh_domain = domain->priv;
	uint32_t l1entry = 0, l2entry = 0;
	unsigned int l1index, l2index;

	l1index = iova >> 20;
	l2index = (iova >> 12) & 0xff;
	spin_lock(&sh_domain->map_lock);
	if (sh_domain->l2[l1index].pgtable)
	l2entry = pgtable_read(&sh_domain->l2[l1index], l2index);
	else
	l1entry = pgtable_read(&sh_domain->l1, l1index);
	spin_unlock(&sh_domain->map_lock);
	switch (l2entry & 3) {
	case 1:
	return (l2entry & ~0xffff) \| (iova & 0xffff);
	case 2:
	return (l2entry & ~0xfff) \| (iova & 0xfff);
	default:
	if ((l1entry & 3) == 2)
	return (l1entry & ~0xfffff) \| (iova & 0xfffff);
	return 0;
	}
	}

	static int find_dev_name(struct shmobile_ipmmu ipmmu, const char dev_name)
	{
	unsigned int i, n = ipmmu->num_dev_names;

	for (i = 0; i < n; i++) {
	if (strcmp(ipmmu->dev_names[i], dev_name) == 0)
	return 1;
	}
	return 0;
	}

	static int shmobile_iommu_add_device(struct device *dev)
	{
	struct shmobile_iommu_archdata *archdata = ipmmu_archdata;
	struct dma_iommu_mapping *mapping;

	if (!find_dev_name(archdata->ipmmu, dev_name(dev)))
	return 0;
	mapping = archdata->iommu_mapping;
	if (!mapping) {
	mapping = arm_iommu_create_mapping(&platform_bus_type, 0,
	L1_LEN << 20);
	if (IS_ERR(mapping))
	return PTR_ERR(mapping);
	archdata->iommu_mapping = mapping;
	}
	dev->archdata.iommu = archdata;
	if (arm_iommu_attach_device(dev, mapping))
	pr_err("arm_iommu_attach_device failed\n");
	return 0;
	}

	static const struct iommu_ops shmobile_iommu_ops = {
	.domain_init = shmobile_iommu_domain_init,
	.domain_destroy = shmobile_iommu_domain_destroy,
	.attach_dev = shmobile_iommu_attach_device,
	.detach_dev = shmobile_iommu_detach_device,
	.map = shmobile_iommu_map,
	.unmap = shmobile_iommu_unmap,
	.map_sg = default_iommu_map_sg,
	.iova_to_phys = shmobile_iommu_iova_to_phys,
	.add_device = shmobile_iommu_add_device,
	.pgsize_bitmap = SZ_1M \| SZ_64K \| SZ_4K,
	};

	int ipmmu_iommu_init(struct shmobile_ipmmu *ipmmu)
	{
	static struct shmobile_iommu_archdata *archdata;

	l1cache = kmem_cache_create("shmobile-iommu-pgtable1", L1_SIZE,
	L1_ALIGN, SLAB_HWCACHE_ALIGN, NULL);
	if (!l1cache)
	return -ENOMEM;
	l2cache = kmem_cache_create("shmobile-iommu-pgtable2", L2_SIZE,
	L2_ALIGN, SLAB_HWCACHE_ALIGN, NULL);
	if (!l2cache) {
	kmem_cache_destroy(l1cache);
	return -ENOMEM;
	}
	archdata = kzalloc(sizeof(*archdata), GFP_KERNEL);
	if (!archdata) {
	kmem_cache_destroy(l1cache);
	kmem_cache_destroy(l2cache);
	return -ENOMEM;
	}
	spin_lock_init(&archdata->attach_lock);
	archdata->ipmmu = ipmmu;
	ipmmu_archdata = archdata;
	bus_set_iommu(&platform_bus_type, &shmobile_iommu_ops);
	return 0;
	}