/* * 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; struct iommu_domain domain; }; static struct shmobile_iommu_archdata *ipmmu_archdata; static struct kmem_cache *l1cache, *l2cache; static struct shmobile_iommu_domain *to_sh_domain(struct iommu_domain *dom) { return container_of(dom, struct shmobile_iommu_domain, domain); } 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 struct iommu_domain *shmobile_iommu_domain_alloc(unsigned type) { struct shmobile_iommu_domain *sh_domain; int i, ret; if (type != IOMMU_DOMAIN_UNMANAGED) return NULL; sh_domain = kzalloc(sizeof(*sh_domain), GFP_KERNEL); if (!sh_domain) return NULL; ret = pgtable_alloc(&sh_domain->l1, l1cache, L1_SIZE); if (ret < 0) { kfree(sh_domain); return NULL; } 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); return &sh_domain->domain; } static void shmobile_iommu_domain_free(struct iommu_domain *domain) { struct shmobile_iommu_domain *sh_domain = to_sh_domain(domain); 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); } 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 = to_sh_domain(domain); 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 = to_sh_domain(domain); 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 = to_sh_domain(domain); 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 = to_sh_domain(domain); 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 = to_sh_domain(domain); 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_alloc = shmobile_iommu_domain_alloc, .domain_free = shmobile_iommu_domain_free, .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; }