1 files changed, 323 insertions, 0 deletions

diff --git a/arch/arm/mach-tegra/include/mach/iovmm.h b/arch/arm/mach-tegra/include/mach/iovmm.h
new file mode 100644
index 00000000000..fd83a326e12
--- /dev/null
+++ b/arch/arm/mach-tegra/include/mach/iovmm.h
@@ -0,0 +1,323 @@
+/*
+ * arch/arm/mach-tegra/include/mach/iovmm.h
+ *
+ * Copyright (c) 2010-2011, NVIDIA Corporation.
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed i the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+#include <linux/list.h>
+#include <linux/platform_device.h>
+#include <linux/miscdevice.h>
+#include <linux/rbtree.h>
+#include <linux/rwsem.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+
+#ifndef _MACH_TEGRA_IOVMM_H_
+#define _MACH_TEGRA_IOVMM_H_
+
+typedef u32 tegra_iovmm_addr_t;
+
+struct tegra_iovmm_device_ops;
+
+/*
+ * each I/O virtual memory manager unit should register a device with
+ * the iovmm system
+ */
+struct tegra_iovmm_device {
+        struct tegra_iovmm_device_ops   *ops;
+        const char                      *name;
+        struct list_head                list;
+        int                             pgsize_bits;
+};
+
+/*
+ * tegra_iovmm_domain serves a purpose analagous to mm_struct as defined in
+ * <linux/mm_types.h> - it defines a virtual address space within which
+ * tegra_iovmm_areas can be created.
+ */
+struct tegra_iovmm_domain {
+        atomic_t                clients;
+        atomic_t                locks;
+        spinlock_t              block_lock;  /* RB-tree for iovmm_area blocks */
+        unsigned long           flags;
+        wait_queue_head_t       delay_lock;  /* when lock_client fails */
+        struct rw_semaphore     map_lock;
+        struct rb_root          all_blocks;  /* ordered by address */
+        struct rb_root          free_blocks; /* ordered by size */
+        struct tegra_iovmm_device *dev;
+};
+
+/*
+ * tegra_iovmm_client is analagous to an individual task in the task group
+ * which owns an mm_struct.
+ */
+
+struct iovmm_share_group;
+
+struct tegra_iovmm_client {
+        const char                      *name;
+        unsigned long                   flags;
+        struct iovmm_share_group        *group;
+        struct tegra_iovmm_domain       *domain;
+        struct miscdevice               *misc_dev;
+        struct list_head                list;
+};
+
+/*
+ * tegra_iovmm_area serves a purpose analagous to vm_area_struct as defined
+ * in <linux/mm_types.h> - it defines a virtual memory area which can be
+ * mapped to physical memory by a client-provided mapping function. */
+
+struct tegra_iovmm_area {
+        struct tegra_iovmm_domain       *domain;
+        tegra_iovmm_addr_t              iovm_start;
+        size_t                          iovm_length;
+        pgprot_t                        pgprot;
+        struct tegra_iovmm_area_ops     *ops;
+};
+
+struct tegra_iovmm_device_ops {
+        /* maps a VMA using the page residency functions provided by the VMA */
+        int (*map)(struct tegra_iovmm_domain *domain,
+                struct tegra_iovmm_area *io_vma);
+        /* marks all PTEs in a VMA as invalid; decommits the virtual addres
+         * space (potentially freeing PDEs when decommit is true.) */
+        void (*unmap)(struct tegra_iovmm_domain *domain,
+                struct tegra_iovmm_area *io_vma, bool decommit);
+        void (*map_pfn)(struct tegra_iovmm_domain *domain,
+                struct tegra_iovmm_area *io_vma,
+                unsigned long offs, unsigned long pfn);
+        /*
+         * ensures that a domain is resident in the hardware's mapping region
+         * so that it may be used by a client
+         */
+        int (*lock_domain)(struct tegra_iovmm_domain *domain,
+                struct tegra_iovmm_client *client);
+        void (*unlock_domain)(struct tegra_iovmm_domain *domain,
+                struct tegra_iovmm_client *client);
+        /*
+         * allocates a vmm_domain for the specified client; may return the same
+         * domain for multiple clients
+         */
+        struct tegra_iovmm_domain* (*alloc_domain)(
+                struct tegra_iovmm_device *dev,
+                struct tegra_iovmm_client *client);
+        void (*free_domain)(struct tegra_iovmm_domain *domain,
+                struct tegra_iovmm_client *client);
+        int (*suspend)(struct tegra_iovmm_device *dev);
+        void (*resume)(struct tegra_iovmm_device *dev);
+};
+
+struct tegra_iovmm_area_ops {
+        /*
+         * ensures that the page of data starting at the specified offset
+         * from the start of the iovma is resident and pinned for use by
+         * DMA, returns the system pfn, or an invalid pfn if the
+         * operation fails.
+         */
+        unsigned long (*lock_makeresident)(struct tegra_iovmm_area *area,
+                tegra_iovmm_addr_t offs);
+        /* called when the page is unmapped from the I/O VMA */
+        void (*release)(struct tegra_iovmm_area *area, tegra_iovmm_addr_t offs);
+};
+
+#ifdef CONFIG_TEGRA_IOVMM
+/*
+ * called by clients to allocate an I/O VMM client mapping context which
+ * will be shared by all clients in the same share_group
+ */
+struct tegra_iovmm_client *tegra_iovmm_alloc_client(const char *name,
+        const char *share_group, struct miscdevice *misc_dev);
+
+size_t tegra_iovmm_get_vm_size(struct tegra_iovmm_client *client);
+
+void tegra_iovmm_free_client(struct tegra_iovmm_client *client);
+
+/*
+ * called by clients to ensure that their mapping context is resident
+ * before performing any DMA operations addressing I/O VMM regions.
+ * client_lock may return -EINTR.
+ */
+int tegra_iovmm_client_lock(struct tegra_iovmm_client *client);
+int tegra_iovmm_client_trylock(struct tegra_iovmm_client *client);
+
+/* called by clients after DMA operations are complete */
+void tegra_iovmm_client_unlock(struct tegra_iovmm_client *client);
+
+/*
+ * called by clients to allocate a new iovmm_area and reserve I/O virtual
+ * address space for it. if ops is NULL, clients should subsequently call
+ * tegra_iovmm_vm_map_pages and/or tegra_iovmm_vm_insert_pfn to explicitly
+ * map the I/O virtual address to an OS-allocated page or physical address,
+ * respectively. VM operations may be called before this call returns
+ */
+struct tegra_iovmm_area *tegra_iovmm_create_vm(
+        struct tegra_iovmm_client *client, struct tegra_iovmm_area_ops *ops,
+        size_t size, size_t align, pgprot_t pgprot, unsigned long iovm_start);
+
+/*
+ * called by clients to "zap" an iovmm_area, and replace all mappings
+ * in it with invalid ones, without freeing the virtual address range
+ */
+void tegra_iovmm_zap_vm(struct tegra_iovmm_area *vm);
+
+/*
+ * after zapping a demand-loaded iovmm_area, the client should unzap it
+ * to allow the VMM device to remap the page range.
+ */
+void tegra_iovmm_unzap_vm(struct tegra_iovmm_area *vm);
+
+/* called by clients to return an iovmm_area to the free pool for the domain */
+void tegra_iovmm_free_vm(struct tegra_iovmm_area *vm);
+
+/* returns size of largest free iovm block */
+size_t tegra_iovmm_get_max_free(struct tegra_iovmm_client *client);
+
+/*
+ * called by client software to map the page-aligned I/O address vaddr to
+ * a specific physical address pfn. I/O VMA should have been created with
+ * a NULL tegra_iovmm_area_ops structure.
+ */
+void tegra_iovmm_vm_insert_pfn(struct tegra_iovmm_area *area,
+        tegra_iovmm_addr_t vaddr, unsigned long pfn);
+
+/*
+ * called by clients to return the iovmm_area containing addr, or NULL if
+ * addr has not been allocated. caller should call tegra_iovmm_area_put when
+ * finished using the returned pointer
+ */
+struct tegra_iovmm_area *tegra_iovmm_find_area_get(
+        struct tegra_iovmm_client *client, tegra_iovmm_addr_t addr);
+
+struct tegra_iovmm_area *tegra_iovmm_area_get(struct tegra_iovmm_area *vm);
+void tegra_iovmm_area_put(struct tegra_iovmm_area *vm);
+
+/* called by drivers to initialize a tegra_iovmm_domain structure */
+int tegra_iovmm_domain_init(struct tegra_iovmm_domain *domain,
+        struct tegra_iovmm_device *dev, tegra_iovmm_addr_t start,
+        tegra_iovmm_addr_t end);
+
+/* called by drivers to register an I/O VMM device with the system */
+int tegra_iovmm_register(struct tegra_iovmm_device *dev);
+
+/* called by drivers to remove an I/O VMM device from the system */
+int tegra_iovmm_unregister(struct tegra_iovmm_device *dev);
+
+#else /* CONFIG_TEGRA_IOVMM */
+
+static inline struct tegra_iovmm_client *tegra_iovmm_alloc_client(
+        const char *name, const char *share_group, struct miscdevice *misc_dev)
+{
+        return NULL;
+}
+
+static inline size_t tegra_iovmm_get_vm_size(struct tegra_iovmm_client *client)
+{
+        return 0;
+}
+
+static inline void tegra_iovmm_free_client(struct tegra_iovmm_client *client)
+{
+}
+
+static inline int tegra_iovmm_client_lock(struct tegra_iovmm_client *client)
+{
+        return 0;
+}
+
+static inline int tegra_iovmm_client_trylock(struct tegra_iovmm_client *client)
+{
+        return 0;
+}
+
+static inline void tegra_iovmm_client_unlock(struct tegra_iovmm_client *client)
+{
+}
+
+static inline struct tegra_iovmm_area *tegra_iovmm_create_vm(
+        struct tegra_iovmm_client *client, struct tegra_iovmm_area_ops *ops,
+        size_t size, size_t align, pgprot_t pgprot, unsigned long iovm_start)
+{
+        return NULL;
+}
+
+static inline void tegra_iovmm_zap_vm(struct tegra_iovmm_area *vm)
+{
+}
+
+static inline void tegra_iovmm_unzap_vm(struct tegra_iovmm_area *vm)
+{
+}
+
+static inline void tegra_iovmm_free_vm(struct tegra_iovmm_area *vm)
+{
+}
+
+static inline size_t tegra_iovmm_get_max_free(struct tegra_iovmm_client *client)
+{
+        return 0;
+}
+
+static inline void tegra_iovmm_vm_insert_pfn(struct tegra_iovmm_area *area,
+        tegra_iovmm_addr_t vaddr, unsigned long pfn)
+{
+}
+
+static inline struct tegra_iovmm_area *tegra_iovmm_find_area_get(
+        struct tegra_iovmm_client *client, tegra_iovmm_addr_t addr)
+{
+        return NULL;
+}
+
+static inline struct tegra_iovmm_area *tegra_iovmm_area_get(
+        struct tegra_iovmm_area *vm)
+{
+        return NULL;
+}
+
+static inline void tegra_iovmm_area_put(struct tegra_iovmm_area *vm)
+{
+}
+
+static inline int tegra_iovmm_domain_init(struct tegra_iovmm_domain *domain,
+        struct tegra_iovmm_device *dev, tegra_iovmm_addr_t start,
+        tegra_iovmm_addr_t end)
+{
+        return 0;
+}
+
+static inline int tegra_iovmm_register(struct tegra_iovmm_device *dev)
+{
+        return 0;
+}
+
+static inline int tegra_iovmm_unregister(struct tegra_iovmm_device *dev)
+{
+        return 0;
+}
+
+static inline int tegra_iovmm_suspend(void)
+{
+        return 0;
+}
+
+static inline void tegra_iovmm_resume(void)
+{
+}
+
+#endif /* CONFIG_TEGRA_IOVMM */
+#endif /* _MACH_TEGRA_IOVMM_H_*/