Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754116Ab1FBWbI (ORCPT ); Thu, 2 Jun 2011 18:31:08 -0400 Received: from mail-ww0-f44.google.com ([74.125.82.44]:51844 "EHLO mail-ww0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752851Ab1FBWbE (ORCPT ); Thu, 2 Jun 2011 18:31:04 -0400 From: Ohad Ben-Cohen To: , , , Cc: , , , , , Ohad Ben-Cohen Subject: [RFC 1/6] omap: iommu: generic iommu api migration Date: Fri, 3 Jun 2011 01:27:38 +0300 Message-Id: <1307053663-24572-2-git-send-email-ohad@wizery.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1307053663-24572-1-git-send-email-ohad@wizery.com> References: <1307053663-24572-1-git-send-email-ohad@wizery.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 13274 Lines: 475 Migrate OMAP's iommu to the generic iommu api, so users can stay generic, and non-omap-specific code can be removed and eventually consolidated into a generic framework. Tested on both OMAP3 and OMAP4. Signed-off-by: Ohad Ben-Cohen --- arch/arm/plat-omap/Kconfig | 7 +- arch/arm/plat-omap/include/plat/iommu.h | 3 +- arch/arm/plat-omap/iommu.c | 288 +++++++++++++++++++++++++++---- arch/arm/plat-omap/iopgtable.h | 18 ++ 4 files changed, 278 insertions(+), 38 deletions(-) diff --git a/arch/arm/plat-omap/Kconfig b/arch/arm/plat-omap/Kconfig index 49a4c75..1c3acb5 100644 --- a/arch/arm/plat-omap/Kconfig +++ b/arch/arm/plat-omap/Kconfig @@ -131,8 +131,13 @@ config OMAP_MBOX_KFIFO_SIZE This can also be changed at runtime (via the mbox_kfifo_size module parameter). +config IOMMU_API + bool + +#can't be tristate; iommu api doesn't support un-registration config OMAP_IOMMU - tristate + bool + select IOMMU_API config OMAP_IOMMU_DEBUG tristate "Export OMAP IOMMU internals in DebugFS" diff --git a/arch/arm/plat-omap/include/plat/iommu.h b/arch/arm/plat-omap/include/plat/iommu.h index 174f1b9..db1c492 100644 --- a/arch/arm/plat-omap/include/plat/iommu.h +++ b/arch/arm/plat-omap/include/plat/iommu.h @@ -167,8 +167,6 @@ extern void iopgtable_lookup_entry(struct iommu *obj, u32 da, u32 **ppgd, extern size_t iopgtable_clear_entry(struct iommu *obj, u32 iova); extern int iommu_set_da_range(struct iommu *obj, u32 start, u32 end); -extern struct iommu *iommu_get(const char *name); -extern void iommu_put(struct iommu *obj); extern int iommu_set_isr(const char *name, int (*isr)(struct iommu *obj, u32 da, u32 iommu_errs, void *priv), @@ -185,5 +183,6 @@ extern int foreach_iommu_device(void *data, extern ssize_t iommu_dump_ctx(struct iommu *obj, char *buf, ssize_t len); extern size_t dump_tlb_entries(struct iommu *obj, char *buf, ssize_t len); +struct device *omap_find_iommu_device(const char *name); #endif /* __MACH_IOMMU_H */ diff --git a/arch/arm/plat-omap/iommu.c b/arch/arm/plat-omap/iommu.c index 34fc31e..f06e99c 100644 --- a/arch/arm/plat-omap/iommu.c +++ b/arch/arm/plat-omap/iommu.c @@ -18,6 +18,8 @@ #include #include #include +#include +#include #include @@ -30,6 +32,19 @@ (__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 iommu *iommu_dev; + struct mutex lock; +}; + /* accommodate the difference between omap1 and omap2/3 */ static const struct iommu_functions *arch_iommu; @@ -852,31 +867,50 @@ int iommu_set_da_range(struct iommu *obj, u32 start, u32 end) EXPORT_SYMBOL_GPL(iommu_set_da_range); /** - * iommu_get - Get iommu handler - * @name: target iommu name + * 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. Users of that API + * may look up the device using PCI credentials when relevent, and when + * not, this helper should be used to find a specific iommu device by name. + * + * This may be relevant to other platforms as well (msm ?) so consider + * moving this to the generic iommu framework. + */ +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 **/ -struct iommu *iommu_get(const char *name) +static struct iommu *omap_iommu_attach(struct device *dev, u32 *iopgd) { int err = -ENOMEM; - struct device *dev; - struct iommu *obj; - - dev = driver_find_device(&omap_iommu_driver.driver, NULL, (void *)name, - device_match_by_alias); - if (!dev) - return ERR_PTR(-ENODEV); - - obj = to_iommu(dev); + struct iommu *obj = to_iommu(dev); mutex_lock(&obj->iommu_lock); - if (obj->refcount++ == 0) { - err = iommu_enable(obj); - if (err) - goto err_enable; - flush_iotlb_all(obj); + /* 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; @@ -893,13 +927,12 @@ err_enable: mutex_unlock(&obj->iommu_lock); return ERR_PTR(err); } -EXPORT_SYMBOL_GPL(iommu_get); /** - * iommu_put - Put back iommu handler + * omap_iommu_detach - release iommu device * @obj: target iommu **/ -void iommu_put(struct iommu *obj) +static void omap_iommu_detach(struct iommu *obj) { if (!obj || IS_ERR(obj)) return; @@ -911,11 +944,12 @@ void iommu_put(struct iommu *obj) module_put(obj->owner); + obj->iopgd = NULL; + mutex_unlock(&obj->iommu_lock); dev_dbg(obj->dev, "%s: %s\n", __func__, obj->name); } -EXPORT_SYMBOL_GPL(iommu_put); int iommu_set_isr(const char *name, int (*isr)(struct iommu *obj, u32 da, u32 iommu_errs, @@ -950,7 +984,6 @@ EXPORT_SYMBOL_GPL(iommu_set_isr); static int __devinit omap_iommu_probe(struct platform_device *pdev) { int err = -ENODEV; - void *p; int irq; struct iommu *obj; struct resource *res; @@ -1009,22 +1042,9 @@ static int __devinit omap_iommu_probe(struct platform_device *pdev) goto err_irq; platform_set_drvdata(pdev, obj); - p = (void *)__get_free_pages(GFP_KERNEL, get_order(IOPGD_TABLE_SIZE)); - if (!p) { - err = -ENOMEM; - goto err_pgd; - } - memset(p, 0, IOPGD_TABLE_SIZE); - clean_dcache_area(p, IOPGD_TABLE_SIZE); - obj->iopgd = p; - - BUG_ON(!IS_ALIGNED((unsigned long)obj->iopgd, IOPGD_TABLE_SIZE)); - dev_info(&pdev->dev, "%s registered\n", obj->name); return 0; -err_pgd: - free_irq(irq, obj); err_irq: iounmap(obj->regbase); err_ioremap: @@ -1072,6 +1092,202 @@ 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 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 = iopgtable_store_entry(oiommu, &e); + if (ret) { + dev_err(dev, "iopgtable_store_entry failed: %d\n", ret); + return ret; + } + + return 0; +} + +static int omap_iommu_unmap(struct iommu_domain *domain, unsigned long da, + int order) +{ + struct omap_iommu_domain *omap_domain = domain->priv; + struct iommu *oiommu = omap_domain->iommu_dev; + struct device *dev = oiommu->dev; + size_t bytes = PAGE_SIZE << order; + size_t ret; + + dev_dbg(dev, "unmapping da 0x%lx size 0x%x\n", da, bytes); + + ret = iopgtable_clear_entry(oiommu, da); + if (ret != bytes) { + dev_err(dev, "entry @ 0x%lx was %d; not %d\n", da, ret, bytes); + return -EINVAL; + } + + return 0; +} + +static int +omap_iommu_attach_dev(struct iommu_domain *domain, struct device *dev) +{ + struct omap_iommu_domain *omap_domain = domain->priv; + struct iommu *oiommu; + int ret = 0; + + mutex_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; + +out: + mutex_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 iommu *oiommu = to_iommu(dev); + + mutex_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: + mutex_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 fail_nomem; + } + + omap_domain->pgtable = (u32 *)__get_free_pages(GFP_KERNEL, + get_order(IOPGD_TABLE_SIZE)); + if (!omap_domain->pgtable) { + pr_err("__get_free_pages failed\n"); + goto fail_nomem; + } + + BUG_ON(!IS_ALIGNED((long)omap_domain->pgtable, IOPGD_TABLE_SIZE)); + memset(omap_domain->pgtable, 0, IOPGD_TABLE_SIZE); + clean_dcache_area(omap_domain->pgtable, IOPGD_TABLE_SIZE); + mutex_init(&omap_domain->lock); + + domain->priv = omap_domain; + + return 0; + +fail_nomem: + kfree(omap_domain); + 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); +} + +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 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; @@ -1084,6 +1300,8 @@ static int __init omap_iommu_init(void) return -ENOMEM; iopte_cachep = p; + register_iommu(&omap_iommu_ops); + return platform_driver_register(&omap_iommu_driver); } module_init(omap_iommu_init); diff --git a/arch/arm/plat-omap/iopgtable.h b/arch/arm/plat-omap/iopgtable.h index c3e93bb..33c7aa9 100644 --- a/arch/arm/plat-omap/iopgtable.h +++ b/arch/arm/plat-omap/iopgtable.h @@ -56,6 +56,19 @@ #define IOPAGE_MASK IOPTE_MASK +/** + * omap_iommu_translate() - va to pa translation + * @d: omap iommu descriptor + * @va: virtual address + * @mask: omap iommu descriptor mask + * + * va to pa translation + */ +static inline phys_addr_t omap_iommu_translate(u32 d, u32 va, u32 mask) +{ + return (d & mask) | (va & (~mask)); +} + /* * some descriptor attributes. */ @@ -64,10 +77,15 @@ #define IOPGD_SUPER (1 << 18 | 2 << 0) #define iopgd_is_table(x) (((x) & 3) == IOPGD_TABLE) +#define iopgd_is_section(x) (((x) & (1 << 18 | 3)) == IOPGD_SECTION) +#define iopgd_is_super(x) (((x) & (1 << 18 | 3)) == IOPGD_SUPER) #define IOPTE_SMALL (2 << 0) #define IOPTE_LARGE (1 << 0) +#define iopte_is_small(x) (((x) & 2) == IOPTE_SMALL) +#define iopte_is_large(x) (((x) & 3) == IOPTE_LARGE) + /* to find an entry in a page-table-directory */ #define iopgd_index(da) (((da) >> IOPGD_SHIFT) & (PTRS_PER_IOPGD - 1)) #define iopgd_offset(obj, da) ((obj)->iopgd + iopgd_index(da)) -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/