Ossama Othman | ff13209 | 2010-03-15 16:23:56 -0700 | [diff] [blame] | 1 | /* |
| 2 | * RAR Handler (/dev/memrar) internal driver API. |
| 3 | * Copyright (C) 2010 Intel Corporation. All rights reserved. |
| 4 | * |
| 5 | * This program is free software; you can redistribute it and/or |
| 6 | * modify it under the terms of version 2 of the GNU General |
| 7 | * Public License as published by the Free Software Foundation. |
| 8 | * |
| 9 | * This program is distributed in the hope that it will be |
| 10 | * useful, but WITHOUT ANY WARRANTY; without even the implied |
| 11 | * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR |
| 12 | * PURPOSE. See the GNU General Public License for more details. |
| 13 | * You should have received a copy of the GNU General Public |
| 14 | * License along with this program; if not, write to the Free |
| 15 | * Software Foundation, Inc., 59 Temple Place - Suite 330, |
| 16 | * Boston, MA 02111-1307, USA. |
| 17 | * The full GNU General Public License is included in this |
| 18 | * distribution in the file called COPYING. |
| 19 | */ |
| 20 | |
| 21 | |
| 22 | #ifndef _MEMRAR_H |
| 23 | #define _MEMRAR_H |
| 24 | |
| 25 | #include <linux/ioctl.h> |
| 26 | #include <linux/types.h> |
| 27 | |
| 28 | |
| 29 | /** |
| 30 | * struct RAR_stat - RAR statistics structure |
| 31 | * @type: Type of RAR memory (e.g., audio vs. video) |
| 32 | * @capacity: Total size of RAR memory region. |
| 33 | * @largest_block_size: Size of the largest reservable block. |
| 34 | * |
| 35 | * This structure is used for RAR_HANDLER_STAT ioctl and for the |
| 36 | * RAR_get_stat() user space wrapper function. |
| 37 | */ |
| 38 | struct RAR_stat { |
| 39 | __u32 type; |
| 40 | __u32 capacity; |
| 41 | __u32 largest_block_size; |
| 42 | }; |
| 43 | |
| 44 | |
| 45 | /** |
| 46 | * struct RAR_block_info - user space struct that describes RAR buffer |
| 47 | * @type: Type of RAR memory (e.g., audio vs. video) |
| 48 | * @size: Requested size of a block to be reserved in RAR. |
| 49 | * @handle: Handle that can be used to refer to reserved block. |
| 50 | * |
| 51 | * This is the basic structure exposed to the user space that |
| 52 | * describes a given RAR buffer. The buffer's underlying bus address |
| 53 | * is not exposed to the user. User space code refers to the buffer |
| 54 | * entirely by "handle". |
| 55 | */ |
| 56 | struct RAR_block_info { |
| 57 | __u32 type; |
| 58 | __u32 size; |
| 59 | __u32 handle; |
| 60 | }; |
| 61 | |
| 62 | |
| 63 | #define RAR_IOCTL_BASE 0xE0 |
| 64 | |
| 65 | /* Reserve RAR block. */ |
| 66 | #define RAR_HANDLER_RESERVE _IOWR(RAR_IOCTL_BASE, 0x00, struct RAR_block_info) |
| 67 | |
| 68 | /* Release previously reserved RAR block. */ |
| 69 | #define RAR_HANDLER_RELEASE _IOW(RAR_IOCTL_BASE, 0x01, __u32) |
| 70 | |
| 71 | /* Get RAR stats. */ |
| 72 | #define RAR_HANDLER_STAT _IOWR(RAR_IOCTL_BASE, 0x02, struct RAR_stat) |
| 73 | |
| 74 | |
| 75 | #ifdef __KERNEL__ |
| 76 | |
| 77 | /* -------------------------------------------------------------- */ |
| 78 | /* Kernel Side RAR Handler Interface */ |
| 79 | /* -------------------------------------------------------------- */ |
| 80 | |
| 81 | /** |
| 82 | * struct RAR_buffer - kernel space struct that describes RAR buffer |
| 83 | * @info: structure containing base RAR buffer information |
| 84 | * @bus_address: buffer bus address |
| 85 | * |
| 86 | * Structure that contains all information related to a given block of |
| 87 | * memory in RAR. It is generally only used when retrieving RAR |
| 88 | * related bus addresses. |
| 89 | * |
| 90 | * Note: This structure is used only by RAR-enabled drivers, and is |
| 91 | * not intended to be exposed to the user space. |
| 92 | */ |
| 93 | struct RAR_buffer { |
| 94 | struct RAR_block_info info; |
| 95 | dma_addr_t bus_address; |
| 96 | }; |
| 97 | |
| 98 | /** |
| 99 | * rar_reserve() - reserve RAR buffers |
| 100 | * @buffers: array of RAR_buffers where type and size of buffers to |
| 101 | * reserve are passed in, handle and bus address are |
| 102 | * passed out |
| 103 | * @count: number of RAR_buffers in the "buffers" array |
| 104 | * |
| 105 | * This function will reserve buffers in the restricted access regions |
| 106 | * of given types. |
| 107 | * |
| 108 | * It returns the number of successfully reserved buffers. Successful |
| 109 | * buffer reservations will have the corresponding bus_address field |
| 110 | * set to a non-zero value in the given buffers vector. |
| 111 | */ |
| 112 | extern size_t rar_reserve(struct RAR_buffer *buffers, |
| 113 | size_t count); |
| 114 | |
| 115 | /** |
| 116 | * rar_release() - release RAR buffers |
| 117 | * @buffers: array of RAR_buffers where handles to buffers to be |
| 118 | * released are passed in |
| 119 | * @count: number of RAR_buffers in the "buffers" array |
| 120 | * |
| 121 | * This function will release RAR buffers that were retrieved through |
| 122 | * a call to rar_reserve() or rar_handle_to_bus() by decrementing the |
| 123 | * reference count. The RAR buffer will be reclaimed when the |
| 124 | * reference count drops to zero. |
| 125 | * |
| 126 | * It returns the number of successfully released buffers. Successful |
| 127 | * releases will have their handle field set to zero in the given |
| 128 | * buffers vector. |
| 129 | */ |
| 130 | extern size_t rar_release(struct RAR_buffer *buffers, |
| 131 | size_t count); |
| 132 | |
| 133 | /** |
| 134 | * rar_handle_to_bus() - convert a vector of RAR handles to bus addresses |
| 135 | * @buffers: array of RAR_buffers containing handles to be |
| 136 | * converted to bus_addresses |
| 137 | * @count: number of RAR_buffers in the "buffers" array |
| 138 | |
| 139 | * This function will retrieve the RAR buffer bus addresses, type and |
| 140 | * size corresponding to the RAR handles provided in the buffers |
| 141 | * vector. |
| 142 | * |
| 143 | * It returns the number of successfully converted buffers. The bus |
| 144 | * address will be set to 0 for unrecognized handles. |
| 145 | * |
| 146 | * The reference count for each corresponding buffer in RAR will be |
| 147 | * incremented. Call rar_release() when done with the buffers. |
| 148 | */ |
| 149 | extern size_t rar_handle_to_bus(struct RAR_buffer *buffers, |
| 150 | size_t count); |
| 151 | |
| 152 | |
| 153 | #endif /* __KERNEL__ */ |
| 154 | |
| 155 | #endif /* _MEMRAR_H */ |