Sylvain Munaut | 2f9ea1b | 2007-09-16 20:53:27 +1000 | [diff] [blame] | 1 | /* |
| 2 | * Public header for the MPC52xx processor BestComm driver |
| 3 | * |
| 4 | * |
| 5 | * Copyright (C) 2006 Sylvain Munaut <tnt@246tNt.com> |
| 6 | * Copyright (C) 2005 Varma Electronics Oy, |
| 7 | * ( by Andrey Volkov <avolkov@varma-el.com> ) |
| 8 | * Copyright (C) 2003-2004 MontaVista, Software, Inc. |
| 9 | * ( by Dale Farnsworth <dfarnsworth@mvista.com> ) |
| 10 | * |
| 11 | * This file is licensed under the terms of the GNU General Public License |
| 12 | * version 2. This program is licensed "as is" without any warranty of any |
| 13 | * kind, whether express or implied. |
| 14 | */ |
| 15 | |
| 16 | #ifndef __BESTCOMM_H__ |
| 17 | #define __BESTCOMM_H__ |
| 18 | |
Grant Likely | 6228824 | 2008-12-21 02:54:27 -0700 | [diff] [blame] | 19 | /** |
| 20 | * struct bcom_bd - Structure describing a generic BestComm buffer descriptor |
| 21 | * @status: The current status of this buffer. Exact meaning depends on the |
| 22 | * task type |
| 23 | * @data: An array of u32 extra data. Size of array is task dependant. |
| 24 | * |
| 25 | * Note: Don't dereference a bcom_bd pointer as an array. The size of the |
| 26 | * bcom_bd is variable. Use bcom_get_bd() instead. |
| 27 | */ |
| 28 | struct bcom_bd { |
| 29 | u32 status; |
| 30 | u32 data[0]; /* variable payload size */ |
| 31 | }; |
Sylvain Munaut | 2f9ea1b | 2007-09-16 20:53:27 +1000 | [diff] [blame] | 32 | |
| 33 | /* ======================================================================== */ |
joe@perches.com | 00d7041 | 2007-12-18 06:30:12 +1100 | [diff] [blame] | 34 | /* Generic task management */ |
Sylvain Munaut | 2f9ea1b | 2007-09-16 20:53:27 +1000 | [diff] [blame] | 35 | /* ======================================================================== */ |
| 36 | |
| 37 | /** |
| 38 | * struct bcom_task - Structure describing a loaded BestComm task |
| 39 | * |
| 40 | * This structure is never built by the driver it self. It's built and |
| 41 | * filled the intermediate layer of the BestComm API, the task dependent |
| 42 | * support code. |
| 43 | * |
| 44 | * Most likely you don't need to poke around inside this structure. The |
| 45 | * fields are exposed in the header just for the sake of inline functions |
| 46 | */ |
| 47 | struct bcom_task { |
| 48 | unsigned int tasknum; |
| 49 | unsigned int flags; |
| 50 | int irq; |
| 51 | |
| 52 | struct bcom_bd *bd; |
| 53 | phys_addr_t bd_pa; |
| 54 | void **cookie; |
| 55 | unsigned short index; |
| 56 | unsigned short outdex; |
| 57 | unsigned int num_bd; |
| 58 | unsigned int bd_size; |
| 59 | |
| 60 | void* priv; |
| 61 | }; |
| 62 | |
| 63 | #define BCOM_FLAGS_NONE 0x00000000ul |
| 64 | #define BCOM_FLAGS_ENABLE_TASK (1ul << 0) |
| 65 | |
| 66 | /** |
| 67 | * bcom_enable - Enable a BestComm task |
| 68 | * @tsk: The BestComm task structure |
| 69 | * |
| 70 | * This function makes sure the given task is enabled and can be run |
| 71 | * by the BestComm engine as needed |
| 72 | */ |
| 73 | extern void bcom_enable(struct bcom_task *tsk); |
| 74 | |
| 75 | /** |
| 76 | * bcom_disable - Disable a BestComm task |
| 77 | * @tsk: The BestComm task structure |
| 78 | * |
| 79 | * This function disable a given task, making sure it's not executed |
| 80 | * by the BestComm engine. |
| 81 | */ |
| 82 | extern void bcom_disable(struct bcom_task *tsk); |
| 83 | |
| 84 | |
| 85 | /** |
| 86 | * bcom_get_task_irq - Returns the irq number of a BestComm task |
| 87 | * @tsk: The BestComm task structure |
| 88 | */ |
| 89 | static inline int |
| 90 | bcom_get_task_irq(struct bcom_task *tsk) { |
| 91 | return tsk->irq; |
| 92 | } |
| 93 | |
| 94 | /* ======================================================================== */ |
| 95 | /* BD based tasks helpers */ |
| 96 | /* ======================================================================== */ |
| 97 | |
Sylvain Munaut | 2f9ea1b | 2007-09-16 20:53:27 +1000 | [diff] [blame] | 98 | #define BCOM_BD_READY 0x40000000ul |
| 99 | |
| 100 | /** _bcom_next_index - Get next input index. |
| 101 | * @tsk: pointer to task structure |
| 102 | * |
| 103 | * Support function; Device drivers should not call this |
| 104 | */ |
| 105 | static inline int |
| 106 | _bcom_next_index(struct bcom_task *tsk) |
| 107 | { |
| 108 | return ((tsk->index + 1) == tsk->num_bd) ? 0 : tsk->index + 1; |
| 109 | } |
| 110 | |
| 111 | /** _bcom_next_outdex - Get next output index. |
| 112 | * @tsk: pointer to task structure |
| 113 | * |
| 114 | * Support function; Device drivers should not call this |
| 115 | */ |
| 116 | static inline int |
| 117 | _bcom_next_outdex(struct bcom_task *tsk) |
| 118 | { |
| 119 | return ((tsk->outdex + 1) == tsk->num_bd) ? 0 : tsk->outdex + 1; |
| 120 | } |
| 121 | |
| 122 | /** |
| 123 | * bcom_queue_empty - Checks if a BestComm task BD queue is empty |
| 124 | * @tsk: The BestComm task structure |
| 125 | */ |
| 126 | static inline int |
| 127 | bcom_queue_empty(struct bcom_task *tsk) |
| 128 | { |
| 129 | return tsk->index == tsk->outdex; |
| 130 | } |
| 131 | |
| 132 | /** |
| 133 | * bcom_queue_full - Checks if a BestComm task BD queue is full |
| 134 | * @tsk: The BestComm task structure |
| 135 | */ |
| 136 | static inline int |
| 137 | bcom_queue_full(struct bcom_task *tsk) |
| 138 | { |
| 139 | return tsk->outdex == _bcom_next_index(tsk); |
| 140 | } |
| 141 | |
| 142 | /** |
Grant Likely | 6228824 | 2008-12-21 02:54:27 -0700 | [diff] [blame] | 143 | * bcom_get_bd - Get a BD from the queue |
| 144 | * @tsk: The BestComm task structure |
| 145 | * index: Index of the BD to fetch |
| 146 | */ |
| 147 | static inline struct bcom_bd |
| 148 | *bcom_get_bd(struct bcom_task *tsk, unsigned int index) |
| 149 | { |
| 150 | /* A cast to (void*) so the address can be incremented by the |
| 151 | * real size instead of by sizeof(struct bcom_bd) */ |
| 152 | return ((void *)tsk->bd) + (index * tsk->bd_size); |
| 153 | } |
| 154 | |
| 155 | /** |
Sylvain Munaut | 2f9ea1b | 2007-09-16 20:53:27 +1000 | [diff] [blame] | 156 | * bcom_buffer_done - Checks if a BestComm |
| 157 | * @tsk: The BestComm task structure |
| 158 | */ |
| 159 | static inline int |
| 160 | bcom_buffer_done(struct bcom_task *tsk) |
| 161 | { |
Grant Likely | 6228824 | 2008-12-21 02:54:27 -0700 | [diff] [blame] | 162 | struct bcom_bd *bd; |
Sylvain Munaut | 2f9ea1b | 2007-09-16 20:53:27 +1000 | [diff] [blame] | 163 | if (bcom_queue_empty(tsk)) |
| 164 | return 0; |
Grant Likely | 6228824 | 2008-12-21 02:54:27 -0700 | [diff] [blame] | 165 | |
| 166 | bd = bcom_get_bd(tsk, tsk->outdex); |
| 167 | return !(bd->status & BCOM_BD_READY); |
Sylvain Munaut | 2f9ea1b | 2007-09-16 20:53:27 +1000 | [diff] [blame] | 168 | } |
| 169 | |
| 170 | /** |
| 171 | * bcom_prepare_next_buffer - clear status of next available buffer. |
| 172 | * @tsk: The BestComm task structure |
| 173 | * |
| 174 | * Returns pointer to next buffer descriptor |
| 175 | */ |
| 176 | static inline struct bcom_bd * |
| 177 | bcom_prepare_next_buffer(struct bcom_task *tsk) |
| 178 | { |
Grant Likely | 6228824 | 2008-12-21 02:54:27 -0700 | [diff] [blame] | 179 | struct bcom_bd *bd; |
| 180 | |
| 181 | bd = bcom_get_bd(tsk, tsk->index); |
| 182 | bd->status = 0; /* cleanup last status */ |
| 183 | return bd; |
Sylvain Munaut | 2f9ea1b | 2007-09-16 20:53:27 +1000 | [diff] [blame] | 184 | } |
| 185 | |
| 186 | static inline void |
| 187 | bcom_submit_next_buffer(struct bcom_task *tsk, void *cookie) |
| 188 | { |
Grant Likely | 6228824 | 2008-12-21 02:54:27 -0700 | [diff] [blame] | 189 | struct bcom_bd *bd = bcom_get_bd(tsk, tsk->index); |
| 190 | |
Sylvain Munaut | 2f9ea1b | 2007-09-16 20:53:27 +1000 | [diff] [blame] | 191 | tsk->cookie[tsk->index] = cookie; |
| 192 | mb(); /* ensure the bd is really up-to-date */ |
Grant Likely | 6228824 | 2008-12-21 02:54:27 -0700 | [diff] [blame] | 193 | bd->status |= BCOM_BD_READY; |
Sylvain Munaut | 2f9ea1b | 2007-09-16 20:53:27 +1000 | [diff] [blame] | 194 | tsk->index = _bcom_next_index(tsk); |
| 195 | if (tsk->flags & BCOM_FLAGS_ENABLE_TASK) |
| 196 | bcom_enable(tsk); |
| 197 | } |
| 198 | |
| 199 | static inline void * |
| 200 | bcom_retrieve_buffer(struct bcom_task *tsk, u32 *p_status, struct bcom_bd **p_bd) |
| 201 | { |
| 202 | void *cookie = tsk->cookie[tsk->outdex]; |
Grant Likely | 6228824 | 2008-12-21 02:54:27 -0700 | [diff] [blame] | 203 | struct bcom_bd *bd = bcom_get_bd(tsk, tsk->outdex); |
| 204 | |
Sylvain Munaut | 2f9ea1b | 2007-09-16 20:53:27 +1000 | [diff] [blame] | 205 | if (p_status) |
Grant Likely | 6228824 | 2008-12-21 02:54:27 -0700 | [diff] [blame] | 206 | *p_status = bd->status; |
Sylvain Munaut | 2f9ea1b | 2007-09-16 20:53:27 +1000 | [diff] [blame] | 207 | if (p_bd) |
Grant Likely | 6228824 | 2008-12-21 02:54:27 -0700 | [diff] [blame] | 208 | *p_bd = bd; |
Sylvain Munaut | 2f9ea1b | 2007-09-16 20:53:27 +1000 | [diff] [blame] | 209 | tsk->outdex = _bcom_next_outdex(tsk); |
| 210 | return cookie; |
| 211 | } |
| 212 | |
| 213 | #endif /* __BESTCOMM_H__ */ |