| /* |
| * 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, 0); |
| 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 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, |
| .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 = kmalloc(sizeof(*archdata), GFP_KERNEL); |
| if (!archdata) { |
| kmem_cache_destroy(l1cache); |
| kmem_cache_destroy(l2cache); |
| return -ENOMEM; |
| } |
| spin_lock_init(&archdata->attach_lock); |
| archdata->attached = NULL; |
| archdata->ipmmu = ipmmu; |
| ipmmu_archdata = archdata; |
| bus_set_iommu(&platform_bus_type, &shmobile_iommu_ops); |
| return 0; |
| } |