diff options
Diffstat (limited to 'drivers/iommu/omap-iommu.c')
| -rw-r--r-- | drivers/iommu/omap-iommu.c | 1245 |
1 files changed, 1245 insertions, 0 deletions
diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c new file mode 100644 index 00000000000..8f32b2bf758 --- /dev/null +++ b/drivers/iommu/omap-iommu.c @@ -0,0 +1,1245 @@ +/* + * omap iommu: tlb and pagetable primitives + * + * Copyright (C) 2008-2010 Nokia Corporation + * + * Written by Hiroshi DOYU <Hiroshi.DOYU@nokia.com>, + * Paul Mundt and Toshihiro Kobayashi + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/err.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/interrupt.h> +#include <linux/ioport.h> +#include <linux/clk.h> +#include <linux/platform_device.h> +#include <linux/iommu.h> +#include <linux/mutex.h> +#include <linux/spinlock.h> + +#include <asm/cacheflush.h> + +#include <plat/iommu.h> + +#include <plat/iopgtable.h> + +#define for_each_iotlb_cr(obj, n, __i, cr) \ + for (__i = 0; \ + (__i < (n)) && (cr = __iotlb_read_cr((obj), __i), true); \ + __i++) + +/** + * struct omap_iommu_domain - omap iommu domain + * @pgtable: the page table + * @iommu_dev: an omap iommu device attached to this domain. only a single + * iommu device can be attached for now. + * @lock: domain lock, should be taken when attaching/detaching + */ +struct omap_iommu_domain { + u32 *pgtable; + struct omap_iommu *iommu_dev; + spinlock_t lock; +}; + +/* accommodate the difference between omap1 and omap2/3 */ +static const struct iommu_functions *arch_iommu; + +static struct platform_driver omap_iommu_driver; +static struct kmem_cache *iopte_cachep; + +/** + * omap_install_iommu_arch - Install archtecure specific iommu functions + * @ops: a pointer to architecture specific iommu functions + * + * There are several kind of iommu algorithm(tlb, pagetable) among + * omap series. This interface installs such an iommu algorighm. + **/ +int omap_install_iommu_arch(const struct iommu_functions *ops) +{ + if (arch_iommu) + return -EBUSY; + + arch_iommu = ops; + return 0; +} +EXPORT_SYMBOL_GPL(omap_install_iommu_arch); + +/** + * omap_uninstall_iommu_arch - Uninstall archtecure specific iommu functions + * @ops: a pointer to architecture specific iommu functions + * + * This interface uninstalls the iommu algorighm installed previously. + **/ +void omap_uninstall_iommu_arch(const struct iommu_functions *ops) +{ + if (arch_iommu != ops) + pr_err("%s: not your arch\n", __func__); + + arch_iommu = NULL; +} +EXPORT_SYMBOL_GPL(omap_uninstall_iommu_arch); + +/** + * omap_iommu_save_ctx - Save registers for pm off-mode support + * @obj: target iommu + **/ +void omap_iommu_save_ctx(struct omap_iommu *obj) +{ + arch_iommu->save_ctx(obj); +} +EXPORT_SYMBOL_GPL(omap_iommu_save_ctx); + +/** + * omap_iommu_restore_ctx - Restore registers for pm off-mode support + * @obj: target iommu + **/ +void omap_iommu_restore_ctx(struct omap_iommu *obj) +{ + arch_iommu->restore_ctx(obj); +} +EXPORT_SYMBOL_GPL(omap_iommu_restore_ctx); + +/** + * omap_iommu_arch_version - Return running iommu arch version + **/ +u32 omap_iommu_arch_version(void) +{ + return arch_iommu->version; +} +EXPORT_SYMBOL_GPL(omap_iommu_arch_version); + +static int iommu_enable(struct omap_iommu *obj) +{ + int err; + + if (!obj) + return -EINVAL; + + if (!arch_iommu) + return -ENODEV; + + clk_enable(obj->clk); + + err = arch_iommu->enable(obj); + + clk_disable(obj->clk); + return err; +} + +static void iommu_disable(struct omap_iommu *obj) +{ + if (!obj) + return; + + clk_enable(obj->clk); + + arch_iommu->disable(obj); + + clk_disable(obj->clk); +} + +/* + * TLB operations + */ +void omap_iotlb_cr_to_e(struct cr_regs *cr, struct iotlb_entry *e) +{ + BUG_ON(!cr || !e); + + arch_iommu->cr_to_e(cr, e); +} +EXPORT_SYMBOL_GPL(omap_iotlb_cr_to_e); + +static inline int iotlb_cr_valid(struct cr_regs *cr) +{ + if (!cr) + return -EINVAL; + + return arch_iommu->cr_valid(cr); +} + +static inline struct cr_regs *iotlb_alloc_cr(struct omap_iommu *obj, + struct iotlb_entry *e) +{ + if (!e) + return NULL; + + return arch_iommu->alloc_cr(obj, e); +} + +static u32 iotlb_cr_to_virt(struct cr_regs *cr) +{ + return arch_iommu->cr_to_virt(cr); +} + +static u32 get_iopte_attr(struct iotlb_entry *e) +{ + return arch_iommu->get_pte_attr(e); +} + +static u32 iommu_report_fault(struct omap_iommu *obj, u32 *da) +{ + return arch_iommu->fault_isr(obj, da); +} + +static 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); + +} + +static 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) +{ + arch_iommu->tlb_read_cr(obj, cr); +} + +static void iotlb_load_cr(struct omap_iommu *obj, struct cr_regs *cr) +{ + arch_iommu->tlb_load_cr(obj, cr); + + iommu_write_reg(obj, 1, MMU_FLUSH_ENTRY); + iommu_write_reg(obj, 1, MMU_LD_TLB); +} + +/** + * iotlb_dump_cr - Dump an iommu tlb entry into buf + * @obj: target iommu + * @cr: contents of cam and ram register + * @buf: output buffer + **/ +static inline ssize_t iotlb_dump_cr(struct omap_iommu *obj, struct cr_regs *cr, + char *buf) +{ + BUG_ON(!cr || !buf); + + return arch_iommu->dump_cr(obj, cr, buf); +} + +/* only used in iotlb iteration for-loop */ +static 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; +} + +/** + * load_iotlb_entry - Set an iommu tlb entry + * @obj: target iommu + * @e: an iommu tlb entry info + **/ +#ifdef PREFETCH_IOTLB +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; + + clk_enable(obj->clk); + + 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)) { + clk_disable(obj->clk); + 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: + clk_disable(obj->clk); + 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; + + clk_enable(obj->clk); + + 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(%x)\n", + __func__, start, da, bytes); + iotlb_load_cr(obj, &cr); + iommu_write_reg(obj, 1, MMU_FLUSH_ENTRY); + } + } + clk_disable(obj->clk); + + 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; + + clk_enable(obj->clk); + + l.base = 0; + l.vict = 0; + iotlb_lock_set(obj, &l); + + iommu_write_reg(obj, 1, MMU_GFLUSH); + + clk_disable(obj->clk); +} + +#if defined(CONFIG_OMAP_IOMMU_DEBUG) || defined(CONFIG_OMAP_IOMMU_DEBUG_MODULE) + +ssize_t omap_iommu_dump_ctx(struct omap_iommu *obj, char *buf, ssize_t bytes) +{ + if (!obj || !buf) + return -EINVAL; + + clk_enable(obj->clk); + + bytes = arch_iommu->dump_ctx(obj, buf, bytes); + + clk_disable(obj->clk); + + return bytes; +} +EXPORT_SYMBOL_GPL(omap_iommu_dump_ctx); + +static int +__dump_tlb_entries(struct omap_iommu *obj, struct cr_regs *crs, int num) +{ + int i; + struct iotlb_lock saved; + struct cr_regs tmp; + struct cr_regs *p = crs; + + clk_enable(obj->clk); + iotlb_lock_get(obj, &saved); + + for_each_iotlb_cr(obj, num, i, tmp) { + if (!iotlb_cr_valid(&tmp)) + continue; + *p++ = tmp; + } + + iotlb_lock_set(obj, &saved); + clk_disable(obj->clk); + + return p - crs; +} + +/** + * omap_dump_tlb_entries - dump cr arrays to given buffer + * @obj: target iommu + * @buf: output buffer + **/ +size_t omap_dump_tlb_entries(struct omap_iommu *obj, char *buf, ssize_t bytes) +{ + int i, num; + struct cr_regs *cr; + char *p = buf; + + num = bytes / sizeof(*cr); + num = min(obj->nr_tlb_entries, num); + + cr = kcalloc(num, sizeof(*cr), GFP_KERNEL); + if (!cr) + return 0; + + num = __dump_tlb_entries(obj, cr, num); + for (i = 0; i < num; i++) + p += iotlb_dump_cr(obj, cr + i, p); + kfree(cr); + + return p - buf; +} +EXPORT_SYMBOL_GPL(omap_dump_tlb_entries); + +int omap_foreach_iommu_device(void *data, int (*fn)(struct device *, void *)) +{ + return driver_for_each_device(&omap_iommu_driver.driver, + NULL, data, fn); +} +EXPORT_SYMBOL_GPL(omap_foreach_iommu_device); + +#endif /* CONFIG_OMAP_IOMMU_DEBUG_MODULE */ + +/* + * H/W pagetable operations + */ +static void flush_iopgd_range(u32 *first, u32 *last) +{ + /* FIXME: L2 cache should be taken care of if it exists */ + do { + asm("mcr p15, 0, %0, c7, c10, 1 @ flush_pgd" + : : "r" (first)); + first += L1_CACHE_BYTES / sizeof(*first); + } while (first <= last); +} + +static void flush_iopte_range(u32 *first, u32 *last) +{ + /* FIXME: L2 cache should be taken care of if it exists */ + do { + asm("mcr p15, 0, %0, c7, c10, 1 @ flush_pte" + : : "r" (first)); + first += L1_CACHE_BYTES / sizeof(*first); + } while (first <= last); +} + +static void iopte_free(u32 *iopte) +{ + /* Note: freed iopte's must be clean ready for re-use */ + kmem_cache_free(iopte_cachep, iopte); +} + +static u32 *iopte_alloc(struct omap_iommu *obj, u32 *iopgd, u32 da) +{ + u32 *iopte; + + /* 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); + + *iopgd = virt_to_phys(iopte) | IOPGD_TABLE; + flush_iopgd_range(iopgd, iopgd); + + dev_vdbg(obj->dev, "%s: a new pte:%p\n", __func__, iopte); + } else { + /* We raced, free the reduniovant table */ + iopte_free(iopte); + } + +pte_ready: + iopte = iopte_offset(iopgd, da); + + 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); + + 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_iopgd_range(iopgd, iopgd); + return 0; +} + +static int iopgd_alloc_super(struct omap_iommu *obj, u32 da, u32 pa, u32 prot) +{ + u32 *iopgd = iopgd_offset(obj, 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_iopgd_range(iopgd, iopgd + 15); + return 0; +} + +static int iopte_alloc_page(struct omap_iommu *obj, u32 da, u32 pa, u32 prot) +{ + u32 *iopgd = iopgd_offset(obj, da); + u32 *iopte = iopte_alloc(obj, iopgd, da); + + if (IS_ERR(iopte)) + return PTR_ERR(iopte); + + *iopte = (pa & IOPAGE_MASK) | prot | IOPTE_SMALL; + flush_iopte_range(iopte, iopte); + + 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); + u32 *iopte = iopte_alloc(obj, iopgd, 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(iopte, iopte + 15); + 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; + BUG(); + break; + } + + 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 + **/ +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; +} +EXPORT_SYMBOL_GPL(omap_iopgtable_store_entry); + +/** + * 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; + + 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)); + flush_iopte_range(iopte, iopte + (nent - 1) * sizeof(*iopte)); + + /* + * 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(iopte); + 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_iopgd_range(iopgd, iopgd + (nent - 1) * sizeof(*iopgd)); +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) +{ + 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); + + if (!*iopgd) + continue; + + if (iopgd_is_table(*iopgd)) + iopte_free(iopte_offset(iopgd, 0)); + + *iopgd = 0; + flush_iopgd_range(iopgd, iopgd); + } + + 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; + + if (!obj->refcount) + return IRQ_NONE; + + clk_enable(obj->clk); + errs = iommu_report_fault(obj, &da); + clk_disable(obj->clk); + 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_disable(obj); + + 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; +} + +static int device_match_by_alias(struct device *dev, void *data) +{ + struct omap_iommu *obj = to_iommu(dev); + const char *name = data; + + pr_debug("%s: %s %s\n", __func__, obj->name, name); + + return strcmp(obj->name, name) == 0; +} + +/** + * omap_find_iommu_device() - find an omap iommu device by name + * @name: name of the iommu device + * + * The generic iommu API requires the caller to provide the device + * he wishes to attach to a certain iommu domain. + * + * Drivers generally should not bother with this as it should just + * be taken care of by the DMA-API using dev_archdata. + * + * This function is provided as an interim solution until the latter + * materializes, and omap3isp is fully migrated to the DMA-API. + */ +struct device *omap_find_iommu_device(const char *name) +{ + return driver_find_device(&omap_iommu_driver.driver, NULL, + (void *)name, + device_match_by_alias); +} +EXPORT_SYMBOL_GPL(omap_find_iommu_device); + +/** + * omap_iommu_attach() - attach iommu device to an iommu domain + * @dev: target omap iommu device + * @iopgd: page table + **/ +static struct omap_iommu *omap_iommu_attach(struct device *dev, u32 *iopgd) +{ + int err = -ENOMEM; + struct omap_iommu *obj = to_iommu(dev); + + spin_lock(&obj->iommu_lock); + + /* an iommu device can only be attached once */ + if (++obj->refcount > 1) { + dev_err(dev, "%s: already attached!\n", obj->name); + err = -EBUSY; + goto err_enable; + } + + obj->iopgd = iopgd; + err = iommu_enable(obj); + if (err) + goto err_enable; + flush_iotlb_all(obj); + + if (!try_module_get(obj->owner)) + goto err_module; + + spin_unlock(&obj->iommu_lock); + + dev_dbg(obj->dev, "%s: %s\n", __func__, obj->name); + return obj; + +err_module: + if (obj->refcount == 1) + iommu_disable(obj); +err_enable: + obj->refcount--; + spin_unlock(&obj->iommu_lock); + return ERR_PTR(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); + + if (--obj->refcount == 0) + iommu_disable(obj); + + module_put(obj->owner); + + obj->iopgd = NULL; + + spin_unlock(&obj->iommu_lock); + + dev_dbg(obj->dev, "%s: %s\n", __func__, obj->name); +} + +/* + * OMAP Device MMU(IOMMU) detection + */ +static int __devinit omap_iommu_probe(struct platform_device *pdev) +{ + int err = -ENODEV; + int irq; + struct omap_iommu *obj; + struct resource *res; + struct iommu_platform_data *pdata = pdev->dev.platform_data; + + if (pdev->num_resources != 2) + return -EINVAL; + + obj = kzalloc(sizeof(*obj) + MMU_REG_SIZE, GFP_KERNEL); + if (!obj) + return -ENOMEM; + + obj->clk = clk_get(&pdev->dev, pdata->clk_name); + if (IS_ERR(obj->clk)) + goto err_clk; + + obj->nr_tlb_entries = pdata->nr_tlb_entries; + obj->name = pdata->name; + obj->dev = &pdev->dev; + obj->ctx = (void *)obj + sizeof(*obj); + obj->da_start = pdata->da_start; + obj->da_end = pdata->da_end; + + spin_lock_init(&obj->iommu_lock); + mutex_init(&obj->mmap_lock); + spin_lock_init(&obj->page_table_lock); + INIT_LIST_HEAD(&obj->mmap); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + err = -ENODEV; + goto err_mem; + } + + res = request_mem_region(res->start, resource_size(res), + dev_name(&pdev->dev)); + if (!res) { + err = -EIO; + goto err_mem; + } + + obj->regbase = ioremap(res->start, resource_size(res)); + if (!obj->regbase) { + err = -ENOMEM; + goto err_ioremap; + } + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + err = -ENODEV; + goto err_irq; + } + err = request_irq(irq, iommu_fault_handler, IRQF_SHARED, + dev_name(&pdev->dev), obj); + if (err < 0) + goto err_irq; + platform_set_drvdata(pdev, obj); + + dev_info(&pdev->dev, "%s registered\n", obj->name); + return 0; + +err_irq: + iounmap(obj->regbase); +err_ioremap: + release_mem_region(res->start, resource_size(res)); +err_mem: + clk_put(obj->clk); +err_clk: + kfree(obj); + return err; +} + +static int __devexit omap_iommu_remove(struct platform_device *pdev) +{ + int irq; + struct resource *res; + struct omap_iommu *obj = platform_get_drvdata(pdev); + + platform_set_drvdata(pdev, NULL); + + iopgtable_clear_entry_all(obj); + + irq = platform_get_irq(pdev, 0); + free_irq(irq, obj); + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + release_mem_region(res->start, resource_size(res)); + iounmap(obj->regbase); + + clk_put(obj->clk); + dev_info(&pdev->dev, "%s removed\n", obj->name); + kfree(obj); + return 0; +} + +static struct platform_driver omap_iommu_driver = { + .probe = omap_iommu_probe, + .remove = __devexit_p(omap_iommu_remove), + .driver = { + .name = "omap-iommu", + }, +}; + +static void iopte_cachep_ctor(void *iopte) +{ + clean_dcache_area(iopte, IOPTE_TABLE_SIZE); +} + +static int omap_iommu_map(struct iommu_domain *domain, unsigned long da, + phys_addr_t pa, int order, int prot) +{ + struct omap_iommu_domain *omap_domain = domain->priv; + struct omap_iommu *oiommu = omap_domain->iommu_dev; + struct device *dev = oiommu->dev; + size_t bytes = PAGE_SIZE << order; + struct iotlb_entry e; + int omap_pgsz; + u32 ret, flags; + + /* we only support mapping a single iommu page for now */ + omap_pgsz = bytes_to_iopgsz(bytes); + if (omap_pgsz < 0) { + dev_err(dev, "invalid size to map: %d\n", bytes); + return -EINVAL; + } + + dev_dbg(dev, "mapping da 0x%lx to pa 0x%x size 0x%x\n", da, pa, bytes); + + flags = omap_pgsz | prot; + + iotlb_init_entry(&e, da, pa, flags); + + ret = omap_iopgtable_store_entry(oiommu, &e); + if (ret) + dev_err(dev, "omap_iopgtable_store_entry failed: %d\n", ret); + + return ret; +} + +static int omap_iommu_unmap(struct iommu_domain *domain, unsigned long da, + int order) +{ + struct omap_iommu_domain *omap_domain = domain->priv; + struct omap_iommu *oiommu = omap_domain->iommu_dev; + struct device *dev = oiommu->dev; + size_t unmap_size; + + dev_dbg(dev, "unmapping da 0x%lx order %d\n", da, order); + + unmap_size = iopgtable_clear_entry(oiommu, da); + + return unmap_size ? get_order(unmap_size) : -EINVAL; +} + +static int +omap_iommu_attach_dev(struct iommu_domain *domain, struct device *dev) +{ + struct omap_iommu_domain *omap_domain = domain->priv; + struct omap_iommu *oiommu; + int ret = 0; + + spin_lock(&omap_domain->lock); + + /* only a single device is supported per domain for now */ + if (omap_domain->iommu_dev) { + dev_err(dev, "iommu domain is already attached\n"); + ret = -EBUSY; + goto out; + } + + /* get a handle to and enable the omap iommu */ + oiommu = omap_iommu_attach(dev, omap_domain->pgtable); + if (IS_ERR(oiommu)) { + ret = PTR_ERR(oiommu); + dev_err(dev, "can't get omap iommu: %d\n", ret); + goto out; + } + + omap_domain->iommu_dev = oiommu; + oiommu->domain = domain; + +out: + spin_unlock(&omap_domain->lock); + return ret; +} + +static void omap_iommu_detach_dev(struct iommu_domain *domain, + struct device *dev) +{ + struct omap_iommu_domain *omap_domain = domain->priv; + struct omap_iommu *oiommu = to_iommu(dev); + + spin_lock(&omap_domain->lock); + + /* only a single device is supported per domain for now */ + if (omap_domain->iommu_dev != oiommu) { + dev_err(dev, "invalid iommu device\n"); + goto out; + } + + iopgtable_clear_entry_all(oiommu); + + omap_iommu_detach(oiommu); + + omap_domain->iommu_dev = NULL; + +out: + spin_unlock(&omap_domain->lock); +} + +static int omap_iommu_domain_init(struct iommu_domain *domain) +{ + struct omap_iommu_domain *omap_domain; + + omap_domain = kzalloc(sizeof(*omap_domain), GFP_KERNEL); + if (!omap_domain) { + pr_err("kzalloc failed\n"); + goto out; + } + + omap_domain->pgtable = kzalloc(IOPGD_TABLE_SIZE, GFP_KERNEL); + if (!omap_domain->pgtable) { + pr_err("kzalloc failed\n"); + goto fail_nomem; + } + + /* + * should never fail, but please keep this around to ensure + * we keep the hardware happy + */ + BUG_ON(!IS_ALIGNED((long)omap_domain->pgtable, IOPGD_TABLE_SIZE)); + + clean_dcache_area(omap_domain->pgtable, IOPGD_TABLE_SIZE); + spin_lock_init(&omap_domain->lock); + + domain->priv = omap_domain; + + return 0; + +fail_nomem: + kfree(omap_domain); +out: + return -ENOMEM; +} + +/* assume device was already detached */ +static void omap_iommu_domain_destroy(struct iommu_domain *domain) +{ + struct omap_iommu_domain *omap_domain = domain->priv; + + domain->priv = NULL; + + kfree(omap_domain->pgtable); + kfree(omap_domain); +} + +static phys_addr_t omap_iommu_iova_to_phys(struct iommu_domain *domain, + unsigned long da) +{ + struct omap_iommu_domain *omap_domain = domain->priv; + struct omap_iommu *oiommu = omap_domain->iommu_dev; + struct device *dev = oiommu->dev; + u32 *pgd, *pte; + phys_addr_t ret = 0; + + 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", *pte); + } 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", *pgd); + } + + return ret; +} + +static int omap_iommu_domain_has_cap(struct iommu_domain *domain, + unsigned long cap) +{ + return 0; +} + +static struct iommu_ops omap_iommu_ops = { + .domain_init = omap_iommu_domain_init, + .domain_destroy = omap_iommu_domain_destroy, + .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, + .domain_has_cap = omap_iommu_domain_has_cap, +}; + +static int __init omap_iommu_init(void) +{ + struct kmem_cache *p; + const unsigned long flags = SLAB_HWCACHE_ALIGN; + size_t align = 1 << 10; /* L2 pagetable alignement */ + + p = kmem_cache_create("iopte_cache", IOPTE_TABLE_SIZE, align, flags, + iopte_cachep_ctor); + if (!p) + return -ENOMEM; + iopte_cachep = p; + + bus_set_iommu(&platform_bus_type, &omap_iommu_ops); + + return platform_driver_register(&omap_iommu_driver); +} +module_init(omap_iommu_init); + +static void __exit omap_iommu_exit(void) +{ + kmem_cache_destroy(iopte_cachep); + + platform_driver_unregister(&omap_iommu_driver); +} +module_exit(omap_iommu_exit); + +MODULE_DESCRIPTION("omap iommu: tlb and pagetable primitives"); +MODULE_ALIAS("platform:omap-iommu"); +MODULE_AUTHOR("Hiroshi DOYU, Paul Mundt and Toshihiro Kobayashi"); +MODULE_LICENSE("GPL v2"); |