Merge topic branch 'hwmem' into integration-linux-ux500

Signed-off-by: Philippe Langlais <philippe.langlais@stericsson.com>

1 files changed, 597 insertions, 0 deletions

diff --git a/include/linux/hwmem.h b/include/linux/hwmem.h
new file mode 100644
index 00000000000..cb9e0dc9aaa
--- /dev/null
+++ b/include/linux/hwmem.h
@@ -0,0 +1,597 @@
+/*
+ * Copyright (C) ST-Ericsson SA 2010
+ *
+ * Hardware memory driver, hwmem
+ *
+ * Author: Marcus Lorentzon <marcus.xm.lorentzon@stericsson.com>
+ * for ST-Ericsson.
+ *
+ * License terms: GNU General Public License (GPL), version 2.
+ */
+
+#ifndef _HWMEM_H_
+#define _HWMEM_H_
+
+#include <linux/types.h>
+
+#if !defined(__KERNEL__)
+#include <sys/types.h>
+#else
+#include <linux/mm_types.h>
+#endif
+
+#define HWMEM_DEFAULT_DEVICE_NAME "hwmem"
+
+/**
+ * @brief Flags defining behavior of allocation
+ */
+enum hwmem_alloc_flags {
+	/**
+	 * @brief Buffered
+	 */
+	HWMEM_ALLOC_HINT_WRITE_COMBINE         = (1 << 0),
+	/**
+	 * @brief Non-buffered
+	 */
+	HWMEM_ALLOC_HINT_NO_WRITE_COMBINE      = (1 << 1),
+	/**
+	 * @brief Cached
+	 */
+	HWMEM_ALLOC_HINT_CACHED                = (1 << 2),
+	/**
+	 * @brief Uncached
+	 */
+	HWMEM_ALLOC_HINT_UNCACHED              = (1 << 3),
+	/**
+	 * @brief Write back
+	 */
+	HWMEM_ALLOC_HINT_CACHE_WB              = (1 << 4),
+	/**
+	 * @brief Write through
+	 */
+	HWMEM_ALLOC_HINT_CACHE_WT              = (1 << 5),
+	/**
+	 * @brief No alloc on write
+	 */
+	HWMEM_ALLOC_HINT_CACHE_NAOW            = (1 << 6),
+	/**
+	 * @brief Alloc on write
+	 */
+	HWMEM_ALLOC_HINT_CACHE_AOW             = (1 << 7),
+	/**
+	 * @brief Inner and outer cache
+	 */
+	HWMEM_ALLOC_HINT_INNER_AND_OUTER_CACHE = (1 << 8),
+	/**
+	 * @brief Inner cache only
+	 */
+	HWMEM_ALLOC_HINT_INNER_CACHE_ONLY      = (1 << 9),
+	/**
+	 * @brief Reserved for use by the cache handler integration
+	 */
+	HWMEM_ALLOC_RESERVED_CHI               = (1 << 31),
+};
+
+/**
+ * @brief Flags defining buffer access mode.
+ */
+enum hwmem_access {
+	/**
+	 * @brief Buffer will be read from.
+	 */
+	HWMEM_ACCESS_READ  = (1 << 0),
+	/**
+	 * @brief Buffer will be written to.
+	 */
+	HWMEM_ACCESS_WRITE = (1 << 1),
+	/**
+	 * @brief Buffer will be imported.
+	 */
+	HWMEM_ACCESS_IMPORT = (1 << 2),
+};
+
+/**
+ * @brief Values defining memory types.
+ */
+enum hwmem_mem_type {
+	/**
+	 * @brief Scattered system memory.
+	 */
+	HWMEM_MEM_SCATTERED_SYS,
+	/**
+	 * @brief Contiguous system memory.
+	 */
+	HWMEM_MEM_CONTIGUOUS_SYS,
+	/**
+	 * @brief Protected system memory.
+	 */
+	HWMEM_MEM_PROTECTED_SYS,
+};
+
+/* User space API */
+
+/**
+ * @see struct hwmem_region.
+ */
+struct hwmem_region_us {
+	__u32 offset;
+	__u32 count;
+	__u32 start;
+	__u32 end;
+	__u32 size;
+};
+
+/**
+ * @brief Alloc request data.
+ */
+struct hwmem_alloc_request {
+	/**
+	 * @brief [in] Size of requested allocation in bytes. Size will be
+	 * aligned to PAGE_SIZE bytes.
+	 */
+	__u32 size;
+	/**
+	 * @brief [in] Flags describing requested allocation options.
+	 */
+	__u32 flags; /* enum hwmem_alloc_flags */
+	/**
+	 * @brief [in] Default access rights for buffer.
+	 */
+	__u32 default_access; /* enum hwmem_access */
+	/**
+	 * @brief [in] Memory type of the buffer.
+	 */
+	__u32 mem_type; /* enum hwmem_mem_type */
+};
+
+/**
+ * @brief Set domain request data.
+ */
+struct hwmem_set_domain_request {
+	/**
+	 * @brief [in] Identifier of buffer to be prepared. If 0 is specified
+	 * the buffer associated with the current file instance will be used.
+	 */
+	__s32 id;
+	/**
+	 * @brief [in] Flags specifying access mode of the operation.
+	 *
+	 * One of HWMEM_ACCESS_READ and HWMEM_ACCESS_WRITE is required.
+	 * For details, @see enum hwmem_access.
+	 */
+	__u32 access; /* enum hwmem_access */
+	/**
+	 * @brief [in] The region of bytes to be prepared.
+	 *
+	 * For details, @see struct hwmem_region.
+	 */
+	struct hwmem_region_us region;
+};
+
+/**
+ * @brief Pin request data.
+ */
+struct hwmem_pin_request {
+	/**
+	 * @brief [in] Identifier of buffer to be pinned. If 0 is specified,
+	 * the buffer associated with the current file instance will be used.
+	 */
+	__s32 id;
+	/**
+	 * @brief [out] Physical address of first word in buffer.
+	 */
+	__u32 phys_addr;
+};
+
+/**
+ * @brief Set access rights request data.
+ */
+struct hwmem_set_access_request {
+	/**
+	 * @brief [in] Identifier of buffer to set access rights for. If 0 is
+	 * specified, the buffer associated with the current file instance will
+	 * be used.
+	 */
+	__s32 id;
+	/**
+	 * @param access Access value indicating what is allowed.
+	 */
+	__u32 access; /* enum hwmem_access */
+	/**
+	 * @param pid Process ID to set rights for.
+	 */
+	pid_t pid;
+};
+
+/**
+ * @brief Get info request data.
+ */
+struct hwmem_get_info_request {
+	/**
+	 * @brief [in] Identifier of buffer to get info about. If 0 is specified,
+	 * the buffer associated with the current file instance will be used.
+	 */
+	__s32 id;
+	/**
+	 * @brief [out] Size in bytes of buffer.
+	 */
+	__u32 size;
+	/**
+	 * @brief [out] Memory type of buffer.
+	 */
+	__u32 mem_type; /* enum hwmem_mem_type */
+	/**
+	 * @brief [out] Access rights for buffer.
+	 */
+	__u32 access; /* enum hwmem_access */
+};
+
+/**
+ * @brief Allocates <size> number of bytes and returns a buffer identifier.
+ *
+ * Input is a pointer to a hwmem_alloc_request struct.
+ *
+ * @return A buffer identifier on success, or a negative error code.
+ */
+#define HWMEM_ALLOC_IOC _IOW('W', 1, struct hwmem_alloc_request)
+
+/**
+ * @brief Allocates <size> number of bytes and associates the created buffer
+ * with the current file instance.
+ *
+ * If the current file instance is already associated with a buffer the call
+ * will fail. Buffers referenced through files instances shall not be released
+ * with HWMEM_RELEASE_IOC, instead the file instance shall be closed.
+ *
+ * Input is a pointer to a hwmem_alloc_request struct.
+ *
+ * @return Zero on success, or a negative error code.
+ */
+#define HWMEM_ALLOC_FD_IOC _IOW('W', 2, struct hwmem_alloc_request)
+
+/**
+ * @brief Releases buffer.
+ *
+ * Buffers are reference counted and will not be destroyed until the last
+ * reference is released. Buffers allocated with ALLOC_FD_IOC shall not be
+ * released with this IOC, @see HWMEM_ALLOC_FD_IOC.
+ *
+ * Input is the buffer identifier.
+ *
+ * @return Zero on success, or a negative error code.
+ */
+#define HWMEM_RELEASE_IOC _IO('W', 3)
+
+/**
+ * Memory Mapping
+ *
+ * To map a hwmem buffer mmap the hwmem fd and supply the buffer identifier as
+ * the offset. If the buffer is linked to the fd and thus have no buffer
+ * identifier supply 0 as the offset. Note that the offset feature of mmap is
+ * disabled in both cases, you can only mmap starting a position 0.
+ */
+
+/**
+ * @brief Prepares the buffer for CPU access.
+ *
+ * Input is a pointer to a hwmem_set_domain_request struct.
+ *
+ * @return Zero on success, or a negative error code.
+ */
+#define HWMEM_SET_CPU_DOMAIN_IOC _IOW('W', 4, struct hwmem_set_domain_request)
+
+/**
+ * DEPRECATED: Set sync domain from driver instead!
+ *
+ * @brief Prepares the buffer for access by any DMA hardware.
+ *
+ * Input is a pointer to a hwmem_set_domain_request struct.
+ *
+ * @return Zero on success, or a negative error code.
+ */
+#define HWMEM_SET_SYNC_DOMAIN_IOC _IOW('W', 5, struct hwmem_set_domain_request)
+
+/**
+ * DEPRECATED: Pin from driver instead!
+ *
+ * @brief Pins the buffer.
+ *
+ * Input is a pointer to a hwmem_pin_request struct. Only contiguous buffers
+ * can be pinned from user space.
+ *
+ * @return Zero on success, or a negative error code.
+ */
+#define HWMEM_PIN_IOC _IOWR('W', 6, struct hwmem_pin_request)
+
+/**
+ * DEPRECATED: Unpin from driver instead!
+ *
+ * @brief Unpins the buffer.
+ *
+ * @return Zero on success, or a negative error code.
+ */
+#define HWMEM_UNPIN_IOC _IO('W', 7)
+
+/**
+ * @brief Set access rights for buffer.
+ *
+ * Input is a pointer to a hwmem_set_access_request struct.
+ *
+ * @return Zero on success, or a negative error code.
+ */
+#define HWMEM_SET_ACCESS_IOC _IOW('W', 8, struct hwmem_set_access_request)
+
+/**
+ * @brief Get buffer information.
+ *
+ * Input is a pointer to a hwmem_get_info_request struct.
+ *
+ * @return Zero on success, or a negative error code.
+ */
+#define HWMEM_GET_INFO_IOC _IOWR('W', 9, struct hwmem_get_info_request)
+
+/**
+ * @brief Export the buffer identifier for use in another process.
+ *
+ * The global name will not increase the buffers reference count and will
+ * therefore not keep the buffer alive.
+ *
+ * Input is the buffer identifier. If 0 is specified the buffer associated with
+ * the current file instance will be exported.
+ *
+ * @return A global buffer name on success, or a negative error code.
+ */
+#define HWMEM_EXPORT_IOC _IO('W', 10)
+
+/**
+ * @brief Import a buffer to allow local access to the buffer.
+ *
+ * Input is the buffer's global name.
+ *
+ * @return The imported buffer's identifier on success, or a negative error
+ * code.
+ */
+#define HWMEM_IMPORT_IOC _IO('W', 11)
+
+/**
+ * @brief Import a buffer to allow local access to the buffer using the current
+ * fd.
+ *
+ * Input is the buffer's global name.
+ *
+ * @return Zero on success, or a negative error code.
+ */
+#define HWMEM_IMPORT_FD_IOC _IO('W', 12)
+
+#ifdef __KERNEL__
+
+/* Kernel API */
+
+/**
+ * @brief Values defining memory domain.
+ */
+enum hwmem_domain {
+	/**
+	 * @brief This value specifies the neutral memory domain. Setting this
+	 * domain will syncronize all supported memory domains.
+	 */
+	HWMEM_DOMAIN_SYNC = 0,
+	/**
+	 * @brief This value specifies the CPU memory domain.
+	 */
+	HWMEM_DOMAIN_CPU,
+};
+
+struct hwmem_alloc;
+
+/**
+ * @brief Structure defining a region of a memory buffer.
+ *
+ * A buffer is defined to contain a number of equally sized blocks. Each block
+ * has a part of it included in the region [<start>-<end>). That is
+ * <end>-<start> bytes. Each block is <size> bytes long. Total number of bytes
+ * in the region is (<end> - <start>) * <count>. First byte of the region is
+ * <offset> + <start> bytes into the buffer.
+ *
+ * Here's an example of a region in a graphics buffer (X = buffer, R = region):
+ *
+ * XXXXXXXXXXXXXXXXXXXX \
+ * XXXXXXXXXXXXXXXXXXXX |-- offset = 60
+ * XXXXXXXXXXXXXXXXXXXX /
+ * XXRRRRRRRRXXXXXXXXXX \
+ * XXRRRRRRRRXXXXXXXXXX |-- count = 4
+ * XXRRRRRRRRXXXXXXXXXX |
+ * XXRRRRRRRRXXXXXXXXXX /
+ * XXXXXXXXXXXXXXXXXXXX
+ * --| start = 2
+ * ----------| end = 10
+ * --------------------| size = 20
+ */
+struct hwmem_region {
+	/**
+	 * @brief The first block's offset from beginning of buffer.
+	 */
+	size_t offset;
+	/**
+	 * @brief The number of blocks included in this region.
+	 */
+	size_t count;
+	/**
+	 * @brief The index of the first byte included in this block.
+	 */
+	size_t start;
+	/**
+	 * @brief The index of the last byte included in this block plus one.
+	 */
+	size_t end;
+	/**
+	 * @brief The size in bytes of each block.
+	 */
+	size_t size;
+};
+
+struct hwmem_mem_chunk {
+	phys_addr_t paddr;
+	size_t size;
+};
+
+/**
+ * @brief Allocates <size> number of bytes.
+ *
+ * @param size Number of bytes to allocate. All allocations are page aligned.
+ * @param flags Allocation options.
+ * @param def_access Default buffer access rights.
+ * @param mem_type Memory type.
+ *
+ * @return Pointer to allocation, or a negative error code.
+ */
+struct hwmem_alloc *hwmem_alloc(size_t size, enum hwmem_alloc_flags flags,
+		enum hwmem_access def_access, enum hwmem_mem_type mem_type);
+
+/**
+ * @brief Release a previously allocated buffer.
+ * When last reference is released, the buffer will be freed.
+ *
+ * @param alloc Buffer to be released.
+ */
+void hwmem_release(struct hwmem_alloc *alloc);
+
+/**
+ * @brief Set the buffer domain and prepare it for access.
+ *
+ * @param alloc Buffer to be prepared.
+ * @param access Flags defining memory access mode of the call.
+ * @param domain Value specifying the memory domain.
+ * @param region Structure defining the minimum area of the buffer to be
+ * prepared.
+ *
+ * @return Zero on success, or a negative error code.
+ */
+int hwmem_set_domain(struct hwmem_alloc *alloc, enum hwmem_access access,
+		enum hwmem_domain domain, struct hwmem_region *region);
+
+/**
+ * @brief Pins the buffer.
+ *
+ * Notice that the number of mem chunks a buffer consists of can change at any
+ * time if the buffer is not pinned. Because of this one can not assume that
+ * pin will succeed if <mem_chunks> has the length specified by a previous call
+ * to pin as the buffer layout may have changed between the calls. There are
+ * two ways of handling this situation, keep redoing the pin procedure till it
+ * succeeds or allocate enough mem chunks for the worst case ("buffer size" /
+ * "page size" mem chunks). Contiguous buffers always require only one mem
+ * chunk.
+ *
+ * @param alloc Buffer to be pinned.
+ * @param mem_chunks Pointer to array of mem chunks.
+ * @param mem_chunks_length Pointer to variable that contains the length of
+ * <mem_chunks> array. On success the number of written mem chunks will be
+ * stored in this variable. If the call fails with -ENOSPC the required length
+ * of <mem_chunks> will be stored in this variable.
+ *
+ * @return Zero on success, or a negative error code.
+ */
+int hwmem_pin(struct hwmem_alloc *alloc, struct hwmem_mem_chunk *mem_chunks,
+						size_t *mem_chunks_length);
+
+/**
+ * @brief Unpins the buffer.
+ *
+ * @param alloc Buffer to be unpinned.
+ */
+void hwmem_unpin(struct hwmem_alloc *alloc);
+
+/**
+ * @brief Map the buffer to user space.
+ *
+ * @param alloc Buffer to be mapped.
+ *
+ * @return Zero on success, or a negative error code.
+ */
+int hwmem_mmap(struct hwmem_alloc *alloc, struct vm_area_struct *vma);
+
+/**
+ * @brief Map the buffer for use in the kernel.
+ *
+ * This function implicitly pins the buffer.
+ *
+ * @param alloc Buffer to be mapped.
+ *
+ * @return Pointer to buffer, or a negative error code.
+ */
+void *hwmem_kmap(struct hwmem_alloc *alloc);
+
+/**
+ * @brief Un-map a buffer previously mapped with hwmem_kmap.
+ *
+ * This function implicitly unpins the buffer.
+ *
+ * @param alloc Buffer to be un-mapped.
+ */
+void hwmem_kunmap(struct hwmem_alloc *alloc);
+
+/**
+ * @brief Set access rights for buffer.
+ *
+ * @param alloc Buffer to set rights for.
+ * @param access Access value indicating what is allowed.
+ * @param pid Process ID to set rights for.
+ */
+int hwmem_set_access(struct hwmem_alloc *alloc, enum hwmem_access access,
+								pid_t pid);
+
+/**
+ * @brief Get buffer information.
+ *
+ * @param alloc Buffer to get information about.
+ * @param size Pointer to size output variable. Can be NULL.
+ * @param size Pointer to memory type output variable. Can be NULL.
+ * @param size Pointer to access rights output variable. Can be NULL.
+ */
+void hwmem_get_info(struct hwmem_alloc *alloc, size_t *size,
+		enum hwmem_mem_type *mem_type, enum hwmem_access *access);
+
+/**
+ * @brief Allocate a global buffer name.
+ * Generated buffer name is valid in all processes. Consecutive calls will get
+ * the same name for the same buffer.
+ *
+ * @param alloc Buffer to be made public.
+ *
+ * @return Positive global name on success, or a negative error code.
+ */
+s32 hwmem_get_name(struct hwmem_alloc *alloc);
+
+/**
+ * @brief Import the global buffer name to allow local access to the buffer.
+ * This call will add a buffer reference. Resulting buffer should be
+ * released with a call to hwmem_release.
+ *
+ * @param name A valid global buffer name.
+ *
+ * @return Pointer to allocation, or a negative error code.
+ */
+struct hwmem_alloc *hwmem_resolve_by_name(s32 name);
+
+/* Integration */
+
+struct hwmem_allocator_api {
+	void *(*alloc)(void *instance, size_t size);
+	void (*free)(void *instance, void *alloc);
+	phys_addr_t (*get_alloc_paddr)(void *alloc);
+	void *(*get_alloc_kaddr)(void *instance, void *alloc);
+	size_t (*get_alloc_size)(void *alloc);
+};
+
+struct hwmem_mem_type_struct {
+	enum hwmem_mem_type id;
+	struct hwmem_allocator_api allocator_api;
+	void *allocator_instance;
+};
+
+extern struct hwmem_mem_type_struct *hwmem_mem_types;
+extern unsigned int hwmem_num_mem_types;
+
+#endif
+
+#endif /* _HWMEM_H_ */