// SPDX-License-Identifier: GPL-2.0-only /* * omap iommu: tlb and pagetable primitives * * Copyright (C) 2008-2010 Nokia Corporation * Copyright (C) 2013-2017 Texas Instruments Incorporated - https://www.ti.com/ * * Written by Hiroshi DOYU <Hiroshi.DOYU@nokia.com>, * Paul Mundt and Toshihiro Kobayashi */ #include <linux/dma-mapping.h> #include <linux/err.h> #include <linux/slab.h> #include <linux/interrupt.h> #include <linux/ioport.h> #include <linux/platform_device.h> #include <linux/iommu.h> #include <linux/omap-iommu.h> #include <linux/mutex.h> #include <linux/spinlock.h> #include <linux/io.h> #include <linux/pm_runtime.h> #include <linux/of.h> #include <linux/of_irq.h> #include <linux/of_platform.h> #include <linux/regmap.h> #include <linux/mfd/syscon.h> #include <linux/platform_data/iommu-omap.h> #include "omap-iopgtable.h" #include "omap-iommu.h" static const struct iommu_ops omap_iommu_ops; #define to_iommu(dev) ((struct omap_iommu *)dev_get_drvdata(dev)) /* bitmap of the page sizes currently supported */ #define OMAP_IOMMU_PGSIZES (SZ_4K | SZ_64K | SZ_1M | SZ_16M) #define MMU_LOCK_BASE_SHIFT 10 #define MMU_LOCK_BASE_MASK (0x1f << MMU_LOCK_BASE_SHIFT) #define MMU_LOCK_BASE(x) \ ((x & MMU_LOCK_BASE_MASK) >> MMU_LOCK_BASE_SHIFT) #define MMU_LOCK_VICT_SHIFT 4 #define MMU_LOCK_VICT_MASK (0x1f << MMU_LOCK_VICT_SHIFT) #define MMU_LOCK_VICT(x) \ ((x & MMU_LOCK_VICT_MASK) >> MMU_LOCK_VICT_SHIFT) static struct platform_driver omap_iommu_driver; static struct kmem_cache *iopte_cachep; /** * to_omap_domain - Get struct omap_iommu_domain from generic iommu_domain * @dom: generic iommu domain handle **/ static struct omap_iommu_domain *to_omap_domain(struct iommu_domain *dom) { return container_of(dom, struct omap_iommu_domain, domain); } /** * omap_iommu_save_ctx - Save registers for pm off-mode support * @dev: client device * * This should be treated as an deprecated API. It is preserved only * to maintain existing functionality for OMAP3 ISP driver. **/ void omap_iommu_save_ctx(struct device *dev) { struct omap_iommu_arch_data *arch_data = dev_iommu_priv_get(dev); struct omap_iommu *obj; u32 *p; int i; if (!arch_data) return; while (arch_data->iommu_dev) { obj = arch_data->iommu_dev; p = obj->ctx; for (i = 0; i < (MMU_REG_SIZE / sizeof(u32)); i++) { p[i] = iommu_read_reg(obj, i * sizeof(u32)); dev_dbg(obj->dev, "%s\t[%02d] %08x\n", __func__, i, p[i]); } arch_data++; } } EXPORT_SYMBOL_GPL(omap_iommu_save_ctx); /** * omap_iommu_restore_ctx - Restore registers for pm off-mode support * @dev: client device * * This should be treated as an deprecated API. It is preserved only * to maintain existing functionality for OMAP3 ISP driver. **/ void omap_iommu_restore_ctx(struct device *dev) { struct omap_iommu_arch_data *arch_data = dev_iommu_priv_get(dev); struct omap_iommu *obj; u32 *p; int i; if (!arch_data) return; while (arch_data->iommu_dev) { obj = arch_data->iommu_dev; p = obj->ctx; for (i = 0; i < (MMU_REG_SIZE / sizeof(u32)); i++) { iommu_write_reg(obj, p[i], i * sizeof(u32)); dev_dbg(obj->dev, "%s\t[%02d] %08x\n", __func__, i, p[i]); } arch_data++; } } EXPORT_SYMBOL_GPL(omap_iommu_restore_ctx); static void dra7_cfg_dspsys_mmu(struct omap_iommu *obj, bool enable) { u32 val, mask; if (!obj->syscfg) return; mask = (1 << (obj->id * DSP_SYS_MMU_CONFIG_EN_SHIFT)); val = enable ? mask : 0; regmap_update_bits(obj->syscfg, DSP_SYS_MMU_CONFIG, mask, val); } static void __iommu_set_twl(struct omap_iommu *obj, bool on) { u32 l = iommu_read_reg(obj, MMU_CNTL); if (on) iommu_write_reg(obj, MMU_IRQ_TWL_MASK, MMU_IRQENABLE); else iommu_write_reg(obj, MMU_IRQ_TLB_MISS_MASK, MMU_IRQENABLE); l &= ~MMU_CNTL_MASK; if (on) l |= (MMU_CNTL_MMU_EN | MMU_CNTL_TWL_EN); else l |= (MMU_CNTL_MMU_EN); iommu_write_reg(obj, l, MMU_CNTL); } static int omap2_iommu_enable(struct omap_iommu *obj) { u32 l, pa; if (!obj->iopgd || !IS_ALIGNED((unsigned long)obj->iopgd, SZ_16K)) return -EINVAL; pa = virt_to_phys(obj->iopgd); if (!IS_ALIGNED(pa, SZ_16K)) return -EINVAL; l = iommu_read_reg(obj, MMU_REVISION); dev_info(obj->dev, "%s: version %d.%d\n", obj->name, (l >> 4) & 0xf, l & 0xf); iommu_write_reg(obj, pa, MMU_TTB); dra7_cfg_dspsys_mmu(obj, true); if (obj->has_bus_err_back) iommu_write_reg(obj, MMU_GP_REG_BUS_ERR_BACK_EN, MMU_GP_REG); __iommu_set_twl(obj, true); return 0; } static void omap2_iommu_disable(struct omap_iommu *obj) { u32 l = iommu_read_reg(obj, MMU_CNTL); l &= ~MMU_CNTL_MASK; iommu_write_reg(obj, l, MMU_CNTL); dra7_cfg_dspsys_mmu(obj, false); dev_dbg(obj->dev, "%s is shutting down\n", obj->name); } static int iommu_enable(struct omap_iommu *obj) { int ret; ret = pm_runtime_get_sync(obj->dev); if (ret < 0) pm_runtime_put_noidle(obj->dev); return ret < 0 ? ret : 0; } static void iommu_disable(struct omap_iommu *obj) { pm_runtime_put_sync(obj->dev); } /* * TLB operations */ static u32 iotlb_cr_to_virt(struct cr_regs *cr) { u32 page_size = cr->cam & MMU_CAM_PGSZ_MASK; u32 mask = get_cam_va_mask(cr->cam & page_size); return cr->cam & mask; } static u32 get_iopte_attr(struct iotlb_entry *e) { u32 attr; attr = e->mixed << 5; attr |= e->endian; attr |= e->elsz >> 3; attr <<= (((e->pgsz == MMU_CAM_PGSZ_4K) || (e->pgsz == MMU_CAM_PGSZ_64K)) ? 0 : 6); return attr; } static u32 iommu_report_fault(struct omap_iommu *obj, u32 *da) { u32 status, fault_addr; status = iommu_read_reg(obj, MMU_IRQSTATUS); status &= MMU_IRQ_MASK; if (!status) { *da = 0; return 0; } fault_addr = iommu_read_reg(obj, MMU_FAULT_AD); *da = fault_addr; iommu_write_reg(obj, status, MMU_IRQSTATUS); return status; } void iotlb_lock_get(struct omap_iommu *obj, struct iotlb_lock *l) { u32 val; val = iommu_read_reg(obj, MMU_LOCK); l->base = MMU_LOCK_BASE(val); l->vict = MMU_LOCK_VICT(val); } void iotlb_lock_set(struct omap_iommu *obj, struct iotlb_lock *l) { u32 val; val = (l->base << MMU_LOCK_BASE_SHIFT); val |= (l->vict << MMU_LOCK_VICT_SHIFT); iommu_write_reg(obj, val, MMU_LOCK); } static void iotlb_read_cr(struct omap_iommu *obj, struct cr_regs *cr) { cr->cam = iommu_read_reg(obj, MMU_READ_CAM); cr->ram = iommu_read_reg(obj, MMU_READ_RAM); } static void iotlb_load_cr(struct omap_iommu *obj, struct cr_regs *cr) { iommu_write_reg(obj, cr->cam | MMU_CAM_V, MMU_CAM); iommu_write_reg(obj, cr->ram, MMU_RAM); iommu_write_reg(obj, 1, MMU_FLUSH_ENTRY); iommu_write_reg(obj, 1, MMU_LD_TLB); } /* only used in iotlb iteration for-loop */ struct cr_regs __iotlb_read_cr(struct omap_iommu *obj, int n) { struct cr_regs cr; struct iotlb_lock l; iotlb_lock_get(obj, &l); l.vict = n; iotlb_lock_set(obj, &l); iotlb_read_cr(obj, &cr); return cr; } #ifdef PREFETCH_IOTLB static struct cr_regs *iotlb_alloc_cr(struct omap_iommu *obj, struct iotlb_entry *e) { struct cr_regs *cr; if (!e) return NULL; if (e->da & ~(get_cam_va_mask(e->pgsz))) { dev_err(obj->dev, "%s:\twrong alignment: %08x\n", __func__, e->da); return ERR_PTR(-EINVAL); } cr = kmalloc(sizeof(*cr), GFP_KERNEL); if (!cr) return ERR_PTR(-ENOMEM); cr->cam = (e->da & MMU_CAM_VATAG_MASK) | e->prsvd | e->pgsz | e->valid; cr->ram = e->pa | e->endian | e->elsz | e->mixed; return cr; } /** * load_iotlb_entry - Set an iommu tlb entry * @obj: target iommu * @e: an iommu tlb entry info **/ static int load_iotlb_entry(struct omap_iommu *obj, struct iotlb_entry *e) { int err = 0; struct iotlb_lock l; struct cr_regs *cr; if (!obj || !obj->nr_tlb_entries || !e) return -EINVAL; pm_runtime_get_sync(obj->dev); iotlb_lock_get(obj, &l); if (l.base == obj->nr_tlb_entries) { dev_warn(obj->dev, "%s: preserve entries full\n", __func__); err = -EBUSY; goto out; } if (!e->prsvd) { int i; struct cr_regs tmp; for_each_iotlb_cr(obj, obj->nr_tlb_entries, i, tmp) if (!iotlb_cr_valid(&tmp)) break; if (i == obj->nr_tlb_entries) { dev_dbg(obj->dev, "%s: full: no entry\n", __func__); err = -EBUSY; goto out; } iotlb_lock_get(obj, &l); } else { l.vict = l.base; iotlb_lock_set(obj, &l); } cr = iotlb_alloc_cr(obj, e); if (IS_ERR(cr)) { pm_runtime_put_sync(obj->dev); return PTR_ERR(cr); } iotlb_load_cr(obj, cr); kfree(cr); if (e->prsvd) l.base++; /* increment victim for next tlb load */ if (++l.vict == obj->nr_tlb_entries) l.vict = l.base; iotlb_lock_set(obj, &l); out: pm_runtime_put_sync(obj->dev); return err; } #else /* !PREFETCH_IOTLB */ static int load_iotlb_entry(struct omap_iommu *obj, struct iotlb_entry *e) { return 0; } #endif /* !PREFETCH_IOTLB */ static int prefetch_iotlb_entry(struct omap_iommu *obj, struct iotlb_entry *e) { return load_iotlb_entry(obj, e); } /** * flush_iotlb_page - Clear an iommu tlb entry * @obj: target iommu * @da: iommu device virtual address * * Clear an iommu tlb entry which includes 'da' address. **/ static void flush_iotlb_page(struct omap_iommu *obj, u32 da) { int i; struct cr_regs cr; pm_runtime_get_sync(obj->dev); for_each_iotlb_cr(obj, obj->nr_tlb_entries, i, cr) { u32 start; size_t bytes; if (!iotlb_cr_valid(&cr)) continue; start = iotlb_cr_to_virt(&cr); bytes = iopgsz_to_bytes(cr.cam & 3); if ((start <= da) && (da < start + bytes)) { dev_dbg(obj->dev, "%s: %08x<=%08x(%zx)\n", __func__, start, da, bytes); iotlb_load_cr(obj, &cr); iommu_write_reg(obj, 1, MMU_FLUSH_ENTRY); break; } } pm_runtime_put_sync(obj->dev); if (i == obj->nr_tlb_entries) dev_dbg(obj->dev, "%s: no page for %08x\n", __func__, da); } /** * flush_iotlb_all - Clear all iommu tlb entries * @obj: target iommu **/ static void flush_iotlb_all(struct omap_iommu *obj) { struct iotlb_lock l; pm_runtime_get_sync(obj->dev); l.base = 0; l.vict = 0; iotlb_lock_set(obj, &l); iommu_write_reg(obj, 1, MMU_GFLUSH); pm_runtime_put_sync(obj->dev); } /* * H/W pagetable operations */ static void flush_iopte_range(struct device *dev, dma_addr_t dma, unsigned long offset, int num_entries) { size_t size = num_entries * sizeof(u32); dma_sync_single_range_for_device(dev, dma, offset, size, DMA_TO_DEVICE); } static void iopte_free(struct omap_iommu *obj, u32 *iopte, bool dma_valid) { dma_addr_t pt_dma; /* Note: freed iopte's must be clean ready for re-use */ if (iopte) { if (dma_valid) { pt_dma = virt_to_phys(iopte); dma_unmap_single(obj->dev, pt_dma, IOPTE_TABLE_SIZE, DMA_TO_DEVICE); } kmem_cache_free(iopte_cachep, iopte); } } static u32 *iopte_alloc(struct omap_iommu *obj, u32 *iopgd, dma_addr_t *pt_dma, u32 da) { u32 *iopte; unsigned long offset = iopgd_index(da) * sizeof(da); /* a table has already existed */ if (*iopgd) goto pte_ready; /* * do the allocation outside the page table lock */ spin_unlock(&obj->page_table_lock); iopte = kmem_cache_zalloc(iopte_cachep, GFP_KERNEL); spin_lock(&obj->page_table_lock); if (!*iopgd) { if (!iopte) return ERR_PTR(-ENOMEM); *pt_dma = dma_map_single(obj->dev, iopte, IOPTE_TABLE_SIZE, DMA_TO_DEVICE); if (dma_mapping_error(obj->dev, *pt_dma)) { dev_err(obj->dev, "DMA map error for L2 table\n"); iopte_free(obj, iopte, false); return ERR_PTR(-ENOMEM); } /* * we rely on dma address and the physical address to be * the same for mapping the L2 table */ if (WARN_ON(*pt_dma != virt_to_phys(iopte))) { dev_err(obj->dev, "DMA translation error for L2 table\n"); dma_unmap_single(obj->dev, *pt_dma, IOPTE_TABLE_SIZE, DMA_TO_DEVICE); iopte_free(obj, iopte, false); return ERR_PTR(-ENOMEM); } *iopgd = virt_to_phys(iopte) | IOPGD_TABLE; flush_iopte_range(obj->dev, obj->pd_dma, offset, 1); dev_vdbg(obj->dev, "%s: a new pte:%p\n", __func__, iopte); } else { /* We raced, free the reduniovant table */ iopte_free(obj, iopte, false); } pte_ready: iopte = iopte_offset(iopgd, da); *pt_dma = iopgd_page_paddr(iopgd); dev_vdbg(obj->dev, "%s: da:%08x pgd:%p *pgd:%08x pte:%p *pte:%08x\n", __func__, da, iopgd, *iopgd, iopte, *iopte); return iopte; } static int iopgd_alloc_section(struct omap_iommu *obj, u32 da, u32 pa, u32 prot) { u32 *iopgd = iopgd_offset(obj, da); unsigned long offset = iopgd_index(da) * sizeof(da); if ((da | pa) & ~IOSECTION_MASK) { dev_err(obj->dev, "%s: %08x:%08x should aligned on %08lx\n", __func__, da, pa, IOSECTION_SIZE); return -EINVAL; } *iopgd = (pa & IOSECTION_MASK) | prot | IOPGD_SECTION; flush_iopte_range(obj->dev, obj->pd_dma, offset, 1); return 0; } static int iopgd_alloc_super(struct omap_iommu *obj, u32 da, u32 pa, u32 prot) { u32 *iopgd = iopgd_offset(obj, da); unsigned long offset = iopgd_index(da) * sizeof(da); int i; if ((da | pa) & ~IOSUPER_MASK) { dev_err(obj->dev, "%s: %08x:%08x should aligned on %08lx\n", __func__, da, pa, IOSUPER_SIZE); return -EINVAL; } for (i = 0; i < 16; i++) *(iopgd + i) = (pa & IOSUPER_MASK) | prot | IOPGD_SUPER; flush_iopte_range(obj->dev, obj->pd_dma, offset, 16); return 0; } static int iopte_alloc_page(struct omap_iommu *obj, u32 da, u32 pa, u32 prot) { u32 *iopgd = iopgd_offset(obj, da); dma_addr_t pt_dma; u32 *iopte = iopte_alloc(obj, iopgd, &pt_dma, da); unsigned long offset = iopte_index(da) * sizeof(da); if (IS_ERR(iopte)) return PTR_ERR(iopte); *iopte = (pa & IOPAGE_MASK) | prot | IOPTE_SMALL; flush_iopte_range(obj->dev, pt_dma, offset, 1); dev_vdbg(obj->dev, "%s: da:%08x pa:%08x pte:%p *pte:%08x\n", __func__, da, pa, iopte, *iopte); return 0; } static int iopte_alloc_large(struct omap_iommu *obj, u32 da, u32 pa, u32 prot) { u32 *iopgd = iopgd_offset(obj, da); dma_addr_t pt_dma; u32 *iopte = iopte_alloc(obj, iopgd, &pt_dma, da); unsigned long offset = iopte_index(da) * sizeof(da); int i; if ((da | pa) & ~IOLARGE_MASK) { dev_err(obj->dev, "%s: %08x:%08x should aligned on %08lx\n", __func__, da, pa, IOLARGE_SIZE); return -EINVAL; } if (IS_ERR(iopte)) return PTR_ERR(iopte); for (i = 0; i < 16; i++) *(iopte + i) = (pa & IOLARGE_MASK) | prot | IOPTE_LARGE; flush_iopte_range(obj->dev, pt_dma, offset, 16); return 0; } static int iopgtable_store_entry_core(struct omap_iommu *obj, struct iotlb_entry *e) { int (*fn)(struct omap_iommu *, u32, u32, u32); u32 prot; int err; if (!obj || !e) return -EINVAL; switch (e->pgsz) { case MMU_CAM_PGSZ_16M: fn = iopgd_alloc_super; break; case MMU_CAM_PGSZ_1M: fn = iopgd_alloc_section; break; case MMU_CAM_PGSZ_64K: fn = iopte_alloc_large; break; case MMU_CAM_PGSZ_4K: fn = iopte_alloc_page; break; default: fn = NULL; break; } if (WARN_ON(!fn)) return -EINVAL; prot = get_iopte_attr(e); spin_lock(&obj->page_table_lock); err = fn(obj, e->da, e->pa, prot); spin_unlock(&obj->page_table_lock); return err; } /** * omap_iopgtable_store_entry - Make an iommu pte entry * @obj: target iommu * @e: an iommu tlb entry info **/ static int omap_iopgtable_store_entry(struct omap_iommu *obj, struct iotlb_entry *e) { int err; flush_iotlb_page(obj, e->da); err = iopgtable_store_entry_core(obj, e); if (!err) prefetch_iotlb_entry(obj, e); return err; } /** * iopgtable_lookup_entry - Lookup an iommu pte entry * @obj: target iommu * @da: iommu device virtual address * @ppgd: iommu pgd entry pointer to be returned * @ppte: iommu pte entry pointer to be returned **/ static void iopgtable_lookup_entry(struct omap_iommu *obj, u32 da, u32 **ppgd, u32 **ppte) { u32 *iopgd, *iopte = NULL; iopgd = iopgd_offset(obj, da); if (!*iopgd) goto out; if (iopgd_is_table(*iopgd)) iopte = iopte_offset(iopgd, da); out: *ppgd = iopgd; *ppte = iopte; } static size_t iopgtable_clear_entry_core(struct omap_iommu *obj, u32 da) { size_t bytes; u32 *iopgd = iopgd_offset(obj, da); int nent = 1; dma_addr_t pt_dma; unsigned long pd_offset = iopgd_index(da) * sizeof(da); unsigned long pt_offset = iopte_index(da) * sizeof(da); if (!*iopgd) return 0; if (iopgd_is_table(*iopgd)) { int i; u32 *iopte = iopte_offset(iopgd, da); bytes = IOPTE_SIZE; if (*iopte & IOPTE_LARGE) { nent *= 16; /* rewind to the 1st entry */ iopte = iopte_offset(iopgd, (da & IOLARGE_MASK)); } bytes *= nent; memset(iopte, 0, nent * sizeof(*iopte)); pt_dma = iopgd_page_paddr(iopgd); flush_iopte_range(obj->dev, pt_dma, pt_offset, nent); /* * do table walk to check if this table is necessary or not */ iopte = iopte_offset(iopgd, 0); for (i = 0; i < PTRS_PER_IOPTE; i++) if (iopte[i]) goto out; iopte_free(obj, iopte, true); nent = 1; /* for the next L1 entry */ } else { bytes = IOPGD_SIZE; if ((*iopgd & IOPGD_SUPER) == IOPGD_SUPER) { nent *= 16; /* rewind to the 1st entry */ iopgd = iopgd_offset(obj, (da & IOSUPER_MASK)); } bytes *= nent; } memset(iopgd, 0, nent * sizeof(*iopgd)); flush_iopte_range(obj->dev, obj->pd_dma, pd_offset, nent); out: return bytes; } /** * iopgtable_clear_entry - Remove an iommu pte entry * @obj: target iommu * @da: iommu device virtual address **/ static size_t iopgtable_clear_entry(struct omap_iommu *obj, u32 da) { size_t bytes; spin_lock(&obj->page_table_lock); bytes = iopgtable_clear_entry_core(obj, da); flush_iotlb_page(obj, da); spin_unlock(&obj->page_table_lock); return bytes; } static void iopgtable_clear_entry_all(struct omap_iommu *obj) { unsigned long offset; int i; spin_lock(&obj->page_table_lock); for (i = 0; i < PTRS_PER_IOPGD; i++) { u32 da; u32 *iopgd; da = i << IOPGD_SHIFT; iopgd = iopgd_offset(obj, da); offset = iopgd_index(da) * sizeof(da); if (!*iopgd) continue; if (iopgd_is_table(*iopgd)) iopte_free(obj, iopte_offset(iopgd, 0), true); *iopgd = 0; flush_iopte_range(obj->dev, obj->pd_dma, offset, 1); } flush_iotlb_all(obj); spin_unlock(&obj->page_table_lock); } /* * Device IOMMU generic operations */ static irqreturn_t iommu_fault_handler(int irq, void *data) { u32 da, errs; u32 *iopgd, *iopte; struct omap_iommu *obj = data; struct iommu_domain *domain = obj->domain; struct omap_iommu_domain *omap_domain = to_omap_domain(domain); if (!omap_domain->dev) return IRQ_NONE; errs = iommu_report_fault(obj, &da); if (errs == 0) return IRQ_HANDLED; /* Fault callback or TLB/PTE Dynamic loading */ if (!report_iommu_fault(domain, obj->dev, da, 0)) return IRQ_HANDLED; iommu_write_reg(obj, 0, MMU_IRQENABLE); iopgd = iopgd_offset(obj, da); if (!iopgd_is_table(*iopgd)) { dev_err(obj->dev, "%s: errs:0x%08x da:0x%08x pgd:0x%p *pgd:px%08x\n", obj->name, errs, da, iopgd, *iopgd); return IRQ_NONE; } iopte = iopte_offset(iopgd, da); dev_err(obj->dev, "%s: errs:0x%08x da:0x%08x pgd:0x%p *pgd:0x%08x pte:0x%p *pte:0x%08x\n", obj->name, errs, da, iopgd, *iopgd, iopte, *iopte); return IRQ_NONE; } /** * omap_iommu_attach() - attach iommu device to an iommu domain * @obj: target omap iommu device * @iopgd: page table **/ static int omap_iommu_attach(struct omap_iommu *obj, u32 *iopgd) { int err; spin_lock(&obj->iommu_lock); obj->pd_dma = dma_map_single(obj->dev, iopgd, IOPGD_TABLE_SIZE, DMA_TO_DEVICE); if (dma_mapping_error(obj->dev, obj->pd_dma)) { dev_err(obj->dev, "DMA map error for L1 table\n"); err = -ENOMEM; goto out_err; } obj->iopgd = iopgd; err = iommu_enable(obj); if (err) goto out_err; flush_iotlb_all(obj); spin_unlock(&obj->iommu_lock); dev_dbg(obj->dev, "%s: %s\n", __func__, obj->name); return 0; out_err: spin_unlock(&obj->iommu_lock); return err; } /** * omap_iommu_detach - release iommu device * @obj: target iommu **/ static void omap_iommu_detach(struct omap_iommu *obj) { if (!obj || IS_ERR(obj)) return; spin_lock(&obj->iommu_lock); dma_unmap_single(obj->dev, obj->pd_dma, IOPGD_TABLE_SIZE, DMA_TO_DEVICE); obj->pd_dma = 0; obj->iopgd = NULL; iommu_disable(obj); spin_unlock(&obj->iommu_lock); dev_dbg(obj->dev, "%s: %s\n", __func__, obj->name); } static void omap_iommu_save_tlb_entries(struct omap_iommu *obj) { struct iotlb_lock lock; struct cr_regs cr; struct cr_regs *tmp; int i; /* check if there are any locked tlbs to save */ iotlb_lock_get(obj, &lock); obj->num_cr_ctx = lock.base; if (!obj->num_cr_ctx) return; tmp = obj->cr_ctx; for_each_iotlb_cr(obj, obj->num_cr_ctx, i, cr) * tmp++ = cr; } static void omap_iommu_restore_tlb_entries(struct omap_iommu *obj) { struct iotlb_lock l; struct cr_regs *tmp; int i; /* no locked tlbs to restore */ if (!obj->num_cr_ctx) return; l.base = 0; tmp = obj->cr_ctx; for (i = 0; i < obj->num_cr_ctx; i++, tmp++) { l.vict = i; iotlb_lock_set(obj, &l); iotlb_load_cr(obj, tmp); } l.base = obj->num_cr_ctx; l.vict = i; iotlb_lock_set(obj, &l); } /** * omap_iommu_domain_deactivate - deactivate attached iommu devices * @domain: iommu domain attached to the target iommu device * * This API allows the client devices of IOMMU devices to suspend * the IOMMUs they control at runtime, after they are idled and * suspended all activity. System Suspend will leverage the PM * driver late callbacks. **/ int omap_iommu_domain_deactivate(struct iommu_domain *domain) { struct omap_iommu_domain *omap_domain = to_omap_domain(domain); struct omap_iommu_device *iommu; struct omap_iommu *oiommu; int i; if (!omap_domain->dev) return 0; iommu = omap_domain->iommus; iommu += (omap_domain->num_iommus - 1); for (i = 0; i < omap_domain->num_iommus; i++, iommu--) { oiommu = iommu->iommu_dev; pm_runtime_put_sync(oiommu->dev); } return 0; } EXPORT_SYMBOL_GPL(omap_iommu_domain_deactivate); /** * omap_iommu_domain_activate - activate attached iommu devices * @domain: iommu domain attached to the target iommu device * * This API allows the client devices of IOMMU devices to resume the * IOMMUs they control at runtime, before they can resume operations. * System Resume will leverage the PM driver late callbacks. **/ int omap_iommu_domain_activate(struct iommu_domain *domain) { struct omap_iommu_domain *omap_domain = to_omap_domain(domain); struct omap_iommu_device *iommu; struct omap_iommu *oiommu; int i; if (!omap_domain->dev) return 0; iommu = omap_domain->iommus; for (i = 0; i < omap_domain->num_iommus; i++, iommu++) { oiommu = iommu->iommu_dev; pm_runtime_get_sync(oiommu->dev); } return 0; } EXPORT_SYMBOL_GPL(omap_iommu_domain_activate); /** * omap_iommu_runtime_suspend - disable an iommu device * @dev: iommu device * * This function performs all that is necessary to disable an * IOMMU device, either during final detachment from a client * device, or during system/runtime suspend of the device. This * includes programming all the appropriate IOMMU registers, and * managing the associated omap_hwmod's state and the device's * reset line. This function also saves the context of any * locked TLBs if suspending. **/ static __maybe_unused int omap_iommu_runtime_suspend(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct iommu_platform_data *pdata = dev_get_platdata(dev); struct omap_iommu *obj = to_iommu(dev); int ret; /* save the TLBs only during suspend, and not for power down */ if (obj->domain && obj->iopgd) omap_iommu_save_tlb_entries(obj); omap2_iommu_disable(obj); if (pdata && pdata->device_idle) pdata->device_idle(pdev); if (pdata && pdata->assert_reset) pdata->assert_reset(pdev, pdata->reset_name); if (pdata && pdata->set_pwrdm_constraint) { ret = pdata->set_pwrdm_constraint(pdev, false, &obj->pwrst); if (ret) { dev_warn(obj->dev, "pwrdm_constraint failed to be reset, status = %d\n", ret); } } return 0; } /** * omap_iommu_runtime_resume - enable an iommu device * @dev: iommu device * * This function performs all that is necessary to enable an * IOMMU device, either during initial attachment to a client * device, or during system/runtime resume of the device. This * includes programming all the appropriate IOMMU registers, and * managing the associated omap_hwmod's state and the device's * reset line. The function also restores any locked TLBs if * resuming after a suspend. **/ static __maybe_unused int omap_iommu_runtime_resume(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct iommu_platform_data *pdata = dev_get_platdata(dev); struct omap_iommu *obj = to_iommu(dev); int ret = 0; if (pdata && pdata->set_pwrdm_constraint) { ret = pdata->set_pwrdm_constraint(pdev, true, &obj->pwrst); if (ret) { dev_warn(obj->dev, "pwrdm_constraint failed to be set, status = %d\n", ret); } } if (pdata && pdata->deassert_reset) { ret = pdata->deassert_reset(pdev, pdata->reset_name); if (ret) { dev_err(dev, "deassert_reset failed: %d\n", ret); return ret; } } if (pdata && pdata->device_enable) pdata->device_enable(pdev); /* restore the TLBs only during resume, and not for power up */ if (obj->domain) omap_iommu_restore_tlb_entries(obj); ret = omap2_iommu_enable(obj); return ret; } /** * omap_iommu_prepare - prepare() dev_pm_ops implementation * @dev: iommu device * * This function performs the necessary checks to determine if the IOMMU * device needs suspending or not. The function checks if the runtime_pm * status of the device is suspended, and returns 1 in that case. This * results in the PM core to skip invoking any of the Sleep PM callbacks * (suspend, suspend_late, resume, resume_early etc). */ static int omap_iommu_prepare(struct device *dev) { if (pm_runtime_status_suspended(dev)) return 1; return 0; } static bool omap_iommu_can_register(struct platform_device *pdev) { struct device_node *np = pdev->dev.of_node; if (!of_device_is_compatible(np, "ti,dra7-dsp-iommu")) return true; /* * restrict IOMMU core registration only for processor-port MDMA MMUs * on DRA7 DSPs */ if ((!strcmp(dev_name(&pdev->dev), "40d01000.mmu")) || (!strcmp(dev_name(&pdev->dev), "41501000.mmu"))) return true; return false; } static int omap_iommu_dra7_get_dsp_system_cfg(struct platform_device *pdev, struct omap_iommu *obj) { struct device_node *np = pdev->dev.of_node; int ret; if (!of_device_is_compatible(np, "ti,dra7-dsp-iommu")) return 0; if (!of_property_read_bool(np, "ti,syscon-mmuconfig")) { dev_err(&pdev->dev, "ti,syscon-mmuconfig property is missing\n"); return -EINVAL; } obj->syscfg = syscon_regmap_lookup_by_phandle(np, "ti,syscon-mmuconfig"); if (IS_ERR(obj->syscfg)) { /* can fail with -EPROBE_DEFER */ ret = PTR_ERR(obj->syscfg); return ret; } if (of_property_read_u32_index(np, "ti,syscon-mmuconfig", 1, &obj->id)) { dev_err(&pdev->dev, "couldn't get the IOMMU instance id within subsystem\n"); return -EINVAL; } if (obj->id != 0 && obj->id != 1) { dev_err(&pdev->dev, "invalid IOMMU instance id\n"); return -EINVAL; } return 0; } /* * OMAP Device MMU(IOMMU) detection */ static int omap_iommu_probe(struct platform_device *pdev) { int err = -ENODEV; int irq; struct omap_iommu *obj; struct resource *res; struct device_node *of = pdev->dev.of_node; if (!of) { pr_err("%s: only DT-based devices are supported\n", __func__); return -ENODEV; } obj = devm_kzalloc(&pdev->dev, sizeof(*obj) + MMU_REG_SIZE, GFP_KERNEL); if (!obj) return -ENOMEM; /* * self-manage the ordering dependencies between omap_device_enable/idle * and omap_device_assert/deassert_hardreset API */ if (pdev->dev.pm_domain) { dev_dbg(&pdev->dev, "device pm_domain is being reset\n"); pdev->dev.pm_domain = NULL; } obj->name = dev_name(&pdev->dev); obj->nr_tlb_entries = 32; err = of_property_read_u32(of, "ti,#tlb-entries", &obj->nr_tlb_entries); if (err && err != -EINVAL) return err; if (obj->nr_tlb_entries != 32 && obj->nr_tlb_entries != 8) return -EINVAL; if (of_find_property(of, "ti,iommu-bus-err-back", NULL)) obj->has_bus_err_back = MMU_GP_REG_BUS_ERR_BACK_EN; obj->dev = &pdev->dev; obj->ctx = (void *)obj + sizeof(*obj); obj->cr_ctx = devm_kzalloc(&pdev->dev, sizeof(*obj->cr_ctx) * obj->nr_tlb_entries, GFP_KERNEL); if (!obj->cr_ctx) return -ENOMEM; spin_lock_init(&obj->iommu_lock); spin_lock_init(&obj->page_table_lock); res = platform_get_resource(pdev, IORESOURCE_MEM, 0); obj->regbase = devm_ioremap_resource(obj->dev, res); if (IS_ERR(obj->regbase)) return PTR_ERR(obj->regbase); err = omap_iommu_dra7_get_dsp_system_cfg(pdev, obj); if (err) return err; irq = platform_get_irq(pdev, 0); if (irq < 0) return -ENODEV; err = devm_request_irq(obj->dev, irq, iommu_fault_handler, IRQF_SHARED, dev_name(obj->dev), obj); if (err < 0) return err; platform_set_drvdata(pdev, obj); if (omap_iommu_can_register(pdev)) { obj->group = iommu_group_alloc(); if (IS_ERR(obj->group)) return PTR_ERR(obj->group); err = iommu_device_sysfs_add(&obj->iommu, obj->dev, NULL, obj->name); if (err) goto out_group; err = iommu_device_register(&obj->iommu, &omap_iommu_ops, &pdev->dev); if (err) goto out_sysfs; } pm_runtime_enable(obj->dev); omap_iommu_debugfs_add(obj); dev_info(&pdev->dev, "%s registered\n", obj->name); /* Re-probe bus to probe device attached to this IOMMU */ bus_iommu_probe(&platform_bus_type); return 0; out_sysfs: iommu_device_sysfs_remove(&obj->iommu); out_group: iommu_group_put(obj->group); return err; } static int omap_iommu_remove(struct platform_device *pdev) { struct omap_iommu *obj = platform_get_drvdata(pdev); if (obj->group) { iommu_group_put(obj->group); obj->group = NULL; iommu_device_sysfs_remove(&obj->iommu); iommu_device_unregister(&obj->iommu); } omap_iommu_debugfs_remove(obj); pm_runtime_disable(obj->dev); dev_info(&pdev->dev, "%s removed\n", obj->name); return 0; } static const struct dev_pm_ops omap_iommu_pm_ops = { .prepare = omap_iommu_prepare, SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, pm_runtime_force_resume) SET_RUNTIME_PM_OPS(omap_iommu_runtime_suspend, omap_iommu_runtime_resume, NULL) }; static const struct of_device_id omap_iommu_of_match[] = { { .compatible = "ti,omap2-iommu" }, { .compatible = "ti,omap4-iommu" }, { .compatible = "ti,dra7-iommu" }, { .compatible = "ti,dra7-dsp-iommu" }, {}, }; static struct platform_driver omap_iommu_driver = { .probe = omap_iommu_probe, .remove = omap_iommu_remove, .driver = { .name = "omap-iommu", .pm = &omap_iommu_pm_ops, .of_match_table = of_match_ptr(omap_iommu_of_match), }, }; static u32 iotlb_init_entry(struct iotlb_entry *e, u32 da, u32 pa, int pgsz) { memset(e, 0, sizeof(*e)); e->da = da; e->pa = pa; e->valid = MMU_CAM_V; e->pgsz = pgsz; e->endian = MMU_RAM_ENDIAN_LITTLE; e->elsz = MMU_RAM_ELSZ_8; e->mixed = 0; return iopgsz_to_bytes(e->pgsz); } static int omap_iommu_map(struct iommu_domain *domain, unsigned long da, phys_addr_t pa, size_t bytes, int prot, gfp_t gfp) { struct omap_iommu_domain *omap_domain = to_omap_domain(domain); struct device *dev = omap_domain->dev; struct omap_iommu_device *iommu; struct omap_iommu *oiommu; struct iotlb_entry e; int omap_pgsz; u32 ret = -EINVAL; int i; omap_pgsz = bytes_to_iopgsz(bytes); if (omap_pgsz < 0) { dev_err(dev, "invalid size to map: %zu\n", bytes); return -EINVAL; } dev_dbg(dev, "mapping da 0x%lx to pa %pa size 0x%zx\n", da, &pa, bytes); iotlb_init_entry(&e, da, pa, omap_pgsz); iommu = omap_domain->iommus; for (i = 0; i < omap_domain->num_iommus; i++, iommu++) { oiommu = iommu->iommu_dev; ret = omap_iopgtable_store_entry(oiommu, &e); if (ret) { dev_err(dev, "omap_iopgtable_store_entry failed: %d\n", ret); break; } } if (ret) { while (i--) { iommu--; oiommu = iommu->iommu_dev; iopgtable_clear_entry(oiommu, da); } } return ret; } static size_t omap_iommu_unmap(struct iommu_domain *domain, unsigned long da, size_t size, struct iommu_iotlb_gather *gather) { struct omap_iommu_domain *omap_domain = to_omap_domain(domain); struct device *dev = omap_domain->dev; struct omap_iommu_device *iommu; struct omap_iommu *oiommu; bool error = false; size_t bytes = 0; int i; dev_dbg(dev, "unmapping da 0x%lx size %zu\n", da, size); iommu = omap_domain->iommus; for (i = 0; i < omap_domain->num_iommus; i++, iommu++) { oiommu = iommu->iommu_dev; bytes = iopgtable_clear_entry(oiommu, da); if (!bytes) error = true; } /* * simplify return - we are only checking if any of the iommus * reported an error, but not if all of them are unmapping the * same number of entries. This should not occur due to the * mirror programming. */ return error ? 0 : bytes; } static int omap_iommu_count(struct device *dev) { struct omap_iommu_arch_data *arch_data = dev_iommu_priv_get(dev); int count = 0; while (arch_data->iommu_dev) { count++; arch_data++; } return count; } /* caller should call cleanup if this function fails */ static int omap_iommu_attach_init(struct device *dev, struct omap_iommu_domain *odomain) { struct omap_iommu_device *iommu; int i; odomain->num_iommus = omap_iommu_count(dev); if (!odomain->num_iommus) return -EINVAL; odomain->iommus = kcalloc(odomain->num_iommus, sizeof(*iommu), GFP_ATOMIC); if (!odomain->iommus) return -ENOMEM; iommu = odomain->iommus; for (i = 0; i < odomain->num_iommus; i++, iommu++) { iommu->pgtable = kzalloc(IOPGD_TABLE_SIZE, GFP_ATOMIC); if (!iommu->pgtable) return -ENOMEM; /* * should never fail, but please keep this around to ensure * we keep the hardware happy */ if (WARN_ON(!IS_ALIGNED((long)iommu->pgtable, IOPGD_TABLE_SIZE))) return -EINVAL; } return 0; } static void omap_iommu_detach_fini(struct omap_iommu_domain *odomain) { int i; struct omap_iommu_device *iommu = odomain->iommus; for (i = 0; iommu && i < odomain->num_iommus; i++, iommu++) kfree(iommu->pgtable); kfree(odomain->iommus); odomain->num_iommus = 0; odomain->iommus = NULL; } static int omap_iommu_attach_dev(struct iommu_domain *domain, struct device *dev) { struct omap_iommu_arch_data *arch_data = dev_iommu_priv_get(dev); struct omap_iommu_domain *omap_domain = to_omap_domain(domain); struct omap_iommu_device *iommu; struct omap_iommu *oiommu; int ret = 0; int i; if (!arch_data || !arch_data->iommu_dev) { dev_err(dev, "device doesn't have an associated iommu\n"); return -EINVAL; } spin_lock(&omap_domain->lock); /* only a single client device can be attached to a domain */ if (omap_domain->dev) { dev_err(dev, "iommu domain is already attached\n"); ret = -EBUSY; goto out; } ret = omap_iommu_attach_init(dev, omap_domain); if (ret) { dev_err(dev, "failed to allocate required iommu data %d\n", ret); goto init_fail; } iommu = omap_domain->iommus; for (i = 0; i < omap_domain->num_iommus; i++, iommu++, arch_data++) { /* configure and enable the omap iommu */ oiommu = arch_data->iommu_dev; ret = omap_iommu_attach(oiommu, iommu->pgtable); if (ret) { dev_err(dev, "can't get omap iommu: %d\n", ret); goto attach_fail; } oiommu->domain = domain; iommu->iommu_dev = oiommu; } omap_domain->dev = dev; goto out; attach_fail: while (i--) { iommu--; arch_data--; oiommu = iommu->iommu_dev; omap_iommu_detach(oiommu); iommu->iommu_dev = NULL; oiommu->domain = NULL; } init_fail: omap_iommu_detach_fini(omap_domain); out: spin_unlock(&omap_domain->lock); return ret; } static void _omap_iommu_detach_dev(struct omap_iommu_domain *omap_domain, struct device *dev) { struct omap_iommu_arch_data *arch_data = dev_iommu_priv_get(dev); struct omap_iommu_device *iommu = omap_domain->iommus; struct omap_iommu *oiommu; int i; if (!omap_domain->dev) { dev_err(dev, "domain has no attached device\n"); return; } /* only a single device is supported per domain for now */ if (omap_domain->dev != dev) { dev_err(dev, "invalid attached device\n"); return; } /* * cleanup in the reverse order of attachment - this addresses * any h/w dependencies between multiple instances, if any */ iommu += (omap_domain->num_iommus - 1); arch_data += (omap_domain->num_iommus - 1); for (i = 0; i < omap_domain->num_iommus; i++, iommu--, arch_data--) { oiommu = iommu->iommu_dev; iopgtable_clear_entry_all(oiommu); omap_iommu_detach(oiommu); iommu->iommu_dev = NULL; oiommu->domain = NULL; } omap_iommu_detach_fini(omap_domain); omap_domain->dev = NULL; } static void omap_iommu_detach_dev(struct iommu_domain *domain, struct device *dev) { struct omap_iommu_domain *omap_domain = to_omap_domain(domain); spin_lock(&omap_domain->lock); _omap_iommu_detach_dev(omap_domain, dev); spin_unlock(&omap_domain->lock); } static struct iommu_domain *omap_iommu_domain_alloc(unsigned type) { struct omap_iommu_domain *omap_domain; if (type != IOMMU_DOMAIN_UNMANAGED) return NULL; omap_domain = kzalloc(sizeof(*omap_domain), GFP_KERNEL); if (!omap_domain) return NULL; spin_lock_init(&omap_domain->lock); omap_domain->domain.geometry.aperture_start = 0; omap_domain->domain.geometry.aperture_end = (1ULL << 32) - 1; omap_domain->domain.geometry.force_aperture = true; return &omap_domain->domain; } static void omap_iommu_domain_free(struct iommu_domain *domain) { struct omap_iommu_domain *omap_domain = to_omap_domain(domain); /* * An iommu device is still attached * (currently, only one device can be attached) ? */ if (omap_domain->dev) _omap_iommu_detach_dev(omap_domain, omap_domain->dev); kfree(omap_domain); } static phys_addr_t omap_iommu_iova_to_phys(struct iommu_domain *domain, dma_addr_t da) { struct omap_iommu_domain *omap_domain = to_omap_domain(domain); struct omap_iommu_device *iommu = omap_domain->iommus; struct omap_iommu *oiommu = iommu->iommu_dev; struct device *dev = oiommu->dev; u32 *pgd, *pte; phys_addr_t ret = 0; /* * all the iommus within the domain will have identical programming, * so perform the lookup using just the first iommu */ iopgtable_lookup_entry(oiommu, da, &pgd, &pte); if (pte) { if (iopte_is_small(*pte)) ret = omap_iommu_translate(*pte, da, IOPTE_MASK); else if (iopte_is_large(*pte)) ret = omap_iommu_translate(*pte, da, IOLARGE_MASK); else dev_err(dev, "bogus pte 0x%x, da 0x%llx", *pte, (unsigned long long)da); } else { if (iopgd_is_section(*pgd)) ret = omap_iommu_translate(*pgd, da, IOSECTION_MASK); else if (iopgd_is_super(*pgd)) ret = omap_iommu_translate(*pgd, da, IOSUPER_MASK); else dev_err(dev, "bogus pgd 0x%x, da 0x%llx", *pgd, (unsigned long long)da); } return ret; } static struct iommu_device *omap_iommu_probe_device(struct device *dev) { struct omap_iommu_arch_data *arch_data, *tmp; struct platform_device *pdev; struct omap_iommu *oiommu; struct device_node *np; int num_iommus, i; /* * Allocate the per-device iommu structure for DT-based devices. * * TODO: Simplify this when removing non-DT support completely from the * IOMMU users. */ if (!dev->of_node) return ERR_PTR(-ENODEV); /* * retrieve the count of IOMMU nodes using phandle size as element size * since #iommu-cells = 0 for OMAP */ num_iommus = of_property_count_elems_of_size(dev->of_node, "iommus", sizeof(phandle)); if (num_iommus < 0) return ERR_PTR(-ENODEV); arch_data = kcalloc(num_iommus + 1, sizeof(*arch_data), GFP_KERNEL); if (!arch_data) return ERR_PTR(-ENOMEM); for (i = 0, tmp = arch_data; i < num_iommus; i++, tmp++) { np = of_parse_phandle(dev->of_node, "iommus", i); if (!np) { kfree(arch_data); return ERR_PTR(-EINVAL); } pdev = of_find_device_by_node(np); if (!pdev) { of_node_put(np); kfree(arch_data); return ERR_PTR(-ENODEV); } oiommu = platform_get_drvdata(pdev); if (!oiommu) { of_node_put(np); kfree(arch_data); return ERR_PTR(-EINVAL); } tmp->iommu_dev = oiommu; tmp->dev = &pdev->dev; of_node_put(np); } dev_iommu_priv_set(dev, arch_data); /* * use the first IOMMU alone for the sysfs device linking. * TODO: Evaluate if a single iommu_group needs to be * maintained for both IOMMUs */ oiommu = arch_data->iommu_dev; return &oiommu->iommu; } static void omap_iommu_release_device(struct device *dev) { struct omap_iommu_arch_data *arch_data = dev_iommu_priv_get(dev); if (!dev->of_node || !arch_data) return; dev_iommu_priv_set(dev, NULL); kfree(arch_data); } static struct iommu_group *omap_iommu_device_group(struct device *dev) { struct omap_iommu_arch_data *arch_data = dev_iommu_priv_get(dev); struct iommu_group *group = ERR_PTR(-EINVAL); if (!arch_data) return ERR_PTR(-ENODEV); if (arch_data->iommu_dev) group = iommu_group_ref_get(arch_data->iommu_dev->group); return group; } static const struct iommu_ops omap_iommu_ops = { .domain_alloc = omap_iommu_domain_alloc, .probe_device = omap_iommu_probe_device, .release_device = omap_iommu_release_device, .device_group = omap_iommu_device_group, .pgsize_bitmap = OMAP_IOMMU_PGSIZES, .default_domain_ops = &(const struct iommu_domain_ops) { .attach_dev = omap_iommu_attach_dev, .detach_dev = omap_iommu_detach_dev, .map = omap_iommu_map, .unmap = omap_iommu_unmap, .iova_to_phys = omap_iommu_iova_to_phys, .free = omap_iommu_domain_free, } }; static int __init omap_iommu_init(void) { struct kmem_cache *p; const slab_flags_t flags = SLAB_HWCACHE_ALIGN; size_t align = 1 << 10; /* L2 pagetable alignement */ struct device_node *np; int ret; np = of_find_matching_node(NULL, omap_iommu_of_match); if (!np) return 0; of_node_put(np); p = kmem_cache_create("iopte_cache", IOPTE_TABLE_SIZE, align, flags, NULL); if (!p) return -ENOMEM; iopte_cachep = p; omap_iommu_debugfs_init(); ret = platform_driver_register(&omap_iommu_driver); if (ret) { pr_err("%s: failed to register driver\n", __func__); goto fail_driver; } ret = bus_set_iommu(&platform_bus_type, &omap_iommu_ops); if (ret) goto fail_bus; return 0; fail_bus: platform_driver_unregister(&omap_iommu_driver); fail_driver: kmem_cache_destroy(iopte_cachep); return ret; } subsys_initcall(omap_iommu_init); /* must be ready before omap3isp is probed */