[158] | 1 | /////////////////////////////////////////////////////////////////////////////////// |
---|
| 2 | // File : drivers.c |
---|
| 3 | // Date : 01/04/2012 |
---|
| 4 | // Author : alain greiner |
---|
| 5 | // Copyright (c) UPMC-LIP6 |
---|
| 6 | /////////////////////////////////////////////////////////////////////////////////// |
---|
[160] | 7 | // The drivers.c and drivers.h files are part ot the GIET nano kernel. |
---|
[158] | 8 | // They contains the drivers for the peripherals available in the SoCLib library: |
---|
| 9 | // - vci_multi_tty |
---|
| 10 | // - vci_multi_timer |
---|
| 11 | // - vci_multi_dma |
---|
| 12 | // - vci_multi_icu |
---|
| 13 | // - vci_gcd |
---|
| 14 | // - vci_frame_buffer |
---|
| 15 | // - vci_block_device |
---|
| 16 | // |
---|
| 17 | // The following global parameters must be defined in the giet_config.h file: |
---|
[165] | 18 | // - NB_CLUSTERS : number of clusters |
---|
| 19 | // - NB_PROCS : number of PROCS per cluster |
---|
| 20 | // - NB_TIMERS : number of TIMERS per cluster |
---|
| 21 | // - NB_DMAS : number of DMA channels |
---|
| 22 | // - NB_TTYS : number of TTY terminals |
---|
| 23 | // - NB_TIMERS : number of TIMERS per cluster |
---|
| 24 | // - CLUSTER_SPAN : address increment between clusters |
---|
[158] | 25 | // |
---|
| 26 | // The following base addresses must be defined in the sys.ld file: |
---|
| 27 | // - seg_icu_base |
---|
| 28 | // - seg_timer_base |
---|
| 29 | // - seg_tty_base |
---|
| 30 | // - seg_gcd_base |
---|
| 31 | // - seg_dma_base |
---|
| 32 | // - seg_fb_base |
---|
| 33 | // - seg_ioc_base |
---|
| 34 | /////////////////////////////////////////////////////////////////////////////////// |
---|
| 35 | |
---|
| 36 | #include <sys_handler.h> |
---|
| 37 | #include <giet_config.h> |
---|
| 38 | #include <drivers.h> |
---|
| 39 | #include <common.h> |
---|
| 40 | #include <hwr_mapping.h> |
---|
| 41 | #include <mips32_registers.h> |
---|
| 42 | #include <ctx_handler.h> |
---|
| 43 | |
---|
| 44 | #if !defined(NB_PROCS) |
---|
| 45 | # error: You must define NB_PROCS in 'giet_config.h' file! |
---|
| 46 | #endif |
---|
| 47 | #if !defined(NB_CLUSTERS) |
---|
| 48 | # error: You must define NB_CLUSTERS in 'giet_config.h' file! |
---|
| 49 | #endif |
---|
| 50 | #if !defined(CLUSTER_SPAN) |
---|
| 51 | # error: You must define CLUSTER_SPAN in 'giet_config.h' file! |
---|
| 52 | #endif |
---|
| 53 | #if !defined(NB_TTYS) |
---|
| 54 | # error: You must define NB_TTYS in 'giet_config.h' file! |
---|
| 55 | #endif |
---|
| 56 | #if !defined(NB_DMAS) |
---|
| 57 | # error: You must define NB_DMAS in 'giet_config.h' file! |
---|
| 58 | #endif |
---|
| 59 | #if !defined(NB_TIMERS) |
---|
| 60 | # error: You must define NB_TIMERS in 'giet_config.h' file! |
---|
| 61 | #endif |
---|
| 62 | |
---|
[165] | 63 | #if (NB_TTYS < 1) |
---|
| 64 | # error: NB_TTYS cannot be smaller than 1! |
---|
| 65 | #endif |
---|
| 66 | |
---|
| 67 | #if (NB_TIMERS < NB_PROCS) |
---|
| 68 | # error: NB_TIMERS must be larger or equal to NB_PROCS! |
---|
| 69 | #endif |
---|
| 70 | |
---|
| 71 | #if (NB_PROCS > 8) |
---|
| 72 | # error: NB_PROCS cannot be larger than 8! |
---|
| 73 | #endif |
---|
| 74 | |
---|
| 75 | #if (NB_DMAS < 1) |
---|
| 76 | # error: NB_DMAS cannot be 0! |
---|
| 77 | #endif |
---|
| 78 | |
---|
| 79 | |
---|
[158] | 80 | ///////////////////////////////////////////////////////////////////////////// |
---|
| 81 | // Global (uncachable) variables |
---|
| 82 | ///////////////////////////////////////////////////////////////////////////// |
---|
| 83 | |
---|
| 84 | #define in_unckdata __attribute__((section (".unckdata"))) |
---|
| 85 | |
---|
| 86 | in_unckdata volatile unsigned int _dma_status[NB_DMAS]; |
---|
| 87 | in_unckdata volatile unsigned char _dma_busy[NB_DMAS] = { [0 ... NB_DMAS-1] = 0 }; |
---|
| 88 | |
---|
| 89 | in_unckdata volatile unsigned char _ioc_status; |
---|
| 90 | in_unckdata volatile unsigned char _ioc_done = 0; |
---|
| 91 | in_unckdata volatile unsigned int _ioc_lock = 0; |
---|
| 92 | |
---|
| 93 | in_unckdata volatile unsigned char _tty_get_buf[NB_TTYS]; |
---|
| 94 | in_unckdata volatile unsigned char _tty_get_full[NB_TTYS] = { [0 ... NB_TTYS-1] = 0 }; |
---|
[165] | 95 | in_unckdata unsigned int _tty_put_lock; |
---|
[158] | 96 | |
---|
| 97 | ////////////////////////////////////////////////////////////////////////////// |
---|
| 98 | // VciMultiTimer driver |
---|
| 99 | ////////////////////////////////////////////////////////////////////////////// |
---|
[165] | 100 | // There is one MULTI-TIMER component per cluster. |
---|
| 101 | // The number of timers per cluster must be larger or equal to the number |
---|
| 102 | // processors (NB_TIMERS >= NB_PROCS), because each processor uses a private |
---|
| 103 | // yimer for context switch. |
---|
[158] | 104 | // The total number of timers is NB_CLUSTERS * NB_TIMERS |
---|
[165] | 105 | // The global timer index = cluster_id*NB_TIMERS + timer_id |
---|
[158] | 106 | ////////////////////////////////////////////////////////////////////////////// |
---|
| 107 | |
---|
| 108 | ////////////////////////////////////////////////////////////////////////////// |
---|
| 109 | // _timer_write() |
---|
| 110 | // |
---|
[165] | 111 | // Write a 32-bit word in a memory mapped register of a timer device, |
---|
| 112 | // identified by the cluster index and the local timer index. |
---|
[158] | 113 | // Returns 0 if success, > 0 if error. |
---|
| 114 | ////////////////////////////////////////////////////////////////////////////// |
---|
[165] | 115 | unsigned int _timer_write( unsigned int cluster_index, |
---|
| 116 | unsigned int timer_index, |
---|
[158] | 117 | unsigned int register_index, |
---|
| 118 | unsigned int value ) |
---|
| 119 | { |
---|
[165] | 120 | unsigned int* timer_address; |
---|
[158] | 121 | |
---|
[165] | 122 | // parameters checking |
---|
| 123 | if ( register_index >= TIMER_SPAN) return 1; |
---|
| 124 | if ( cluster_index >= NB_CLUSTERS) return 1; |
---|
| 125 | if ( timer_index >= NB_TIMERS ) return 1; |
---|
[158] | 126 | |
---|
| 127 | timer_address = (unsigned int*)&seg_timer_base + |
---|
[165] | 128 | ( cluster_index * CLUSTER_SPAN ) + |
---|
| 129 | ( timer_index * TIMER_SPAN ); |
---|
[158] | 130 | |
---|
[165] | 131 | timer_address[register_index] = value; // write word |
---|
[158] | 132 | |
---|
| 133 | return 0; |
---|
| 134 | } |
---|
| 135 | |
---|
| 136 | ////////////////////////////////////////////////////////////////////////////// |
---|
| 137 | // _timer_read() |
---|
| 138 | // |
---|
[165] | 139 | // Read a 32-bit word in a memory mapped register of a timer device, |
---|
| 140 | // identified by the cluster index and the local timer index. |
---|
[158] | 141 | // Returns 0 if success, > 0 if error. |
---|
| 142 | ////////////////////////////////////////////////////////////////////////////// |
---|
[165] | 143 | unsigned int _timer_read(unsigned int cluster_index, |
---|
| 144 | unsigned int timer_index, |
---|
[158] | 145 | unsigned int register_index, |
---|
| 146 | unsigned int *buffer) |
---|
| 147 | { |
---|
[165] | 148 | unsigned int *timer_address; |
---|
[158] | 149 | |
---|
[165] | 150 | // parameters checking |
---|
| 151 | if ( register_index >= TIMER_SPAN) return 1; |
---|
| 152 | if ( cluster_index >= NB_CLUSTERS) return 1; |
---|
| 153 | if ( timer_index >= NB_TIMERS ) return 1; |
---|
[158] | 154 | |
---|
| 155 | timer_address = (unsigned int*)&seg_timer_base + |
---|
[165] | 156 | ( cluster_index * CLUSTER_SPAN ) + |
---|
| 157 | ( timer_index * TIMER_SPAN ); |
---|
[158] | 158 | |
---|
[165] | 159 | *buffer = timer_address[register_index]; // read word |
---|
[158] | 160 | |
---|
| 161 | return 0; |
---|
| 162 | } |
---|
| 163 | |
---|
| 164 | ///////////////////////////////////////////////////////////////////////////////// |
---|
| 165 | // VciMultiTty driver |
---|
| 166 | ///////////////////////////////////////////////////////////////////////////////// |
---|
| 167 | // The total number of TTYs is defined by the configuration parameter NB_TTYS. |
---|
| 168 | // The system terminal is TTY[0]. |
---|
| 169 | // The TTYs are allocated to applications by the GIET in the boot phase. |
---|
[165] | 170 | // The nummber of TTYs allocated to each application, and used by each |
---|
[158] | 171 | // task can be defined in the mapping_info data structure. |
---|
| 172 | // For each user task, the tty_id is stored in the context of the task (slot 34), |
---|
| 173 | // and must be explicitely defined in the boot code. |
---|
| 174 | // The TTY address is always computed as : seg_tty_base + tty_id*TTY_SPAN |
---|
| 175 | /////////////////////////////////////////////////////////////////////////////////// |
---|
| 176 | |
---|
| 177 | ////////////////////////////////////////////////////////////////////////////// |
---|
| 178 | // _tty_write() |
---|
| 179 | // |
---|
| 180 | // Write one or several characters directly from a fixed-length user buffer to |
---|
| 181 | // the TTY_WRITE register of the TTY controler. |
---|
| 182 | // It doesn't use the TTY_PUT_IRQ interrupt and the associated kernel buffer. |
---|
| 183 | // This is a non blocking call: it tests the TTY_STATUS register, and stops |
---|
| 184 | // the transfer as soon as the TTY_STATUS[WRITE] bit is set. |
---|
| 185 | // The function returns the number of characters that have been written. |
---|
| 186 | ////////////////////////////////////////////////////////////////////////////// |
---|
[165] | 187 | unsigned int _tty_write( const char *buffer, |
---|
| 188 | unsigned int length) |
---|
[158] | 189 | { |
---|
| 190 | volatile unsigned int *tty_address; |
---|
| 191 | |
---|
| 192 | unsigned int proc_id; |
---|
| 193 | unsigned int task_id; |
---|
| 194 | unsigned int tty_id; |
---|
| 195 | unsigned int nwritten; |
---|
| 196 | |
---|
| 197 | proc_id = _procid(); |
---|
[160] | 198 | |
---|
[158] | 199 | task_id = _scheduler[proc_id].current; |
---|
| 200 | tty_id = _scheduler[proc_id].context[task_id][CTX_TTY_ID]; |
---|
| 201 | |
---|
| 202 | tty_address = (unsigned int*)&seg_tty_base + tty_id*TTY_SPAN; |
---|
| 203 | |
---|
| 204 | for (nwritten = 0; nwritten < length; nwritten++) |
---|
| 205 | { |
---|
[165] | 206 | // check tty's status |
---|
[158] | 207 | if ((tty_address[TTY_STATUS] & 0x2) == 0x2) |
---|
| 208 | break; |
---|
| 209 | else |
---|
[165] | 210 | // write character |
---|
[158] | 211 | tty_address[TTY_WRITE] = (unsigned int)buffer[nwritten]; |
---|
| 212 | } |
---|
| 213 | return nwritten; |
---|
| 214 | } |
---|
| 215 | |
---|
| 216 | ////////////////////////////////////////////////////////////////////////////// |
---|
| 217 | // _tty_read_irq() |
---|
| 218 | // |
---|
| 219 | // This non-blocking function uses the TTY_GET_IRQ[tty_id] interrupt and |
---|
[165] | 220 | // the associated kernel buffer, that has been written by the ISR. |
---|
[158] | 221 | // It fetches one single character from the _tty_get_buf[tty_id] kernel |
---|
| 222 | // buffer, writes this character to the user buffer, and resets the |
---|
| 223 | // _tty_get_full[tty_id] buffer. |
---|
| 224 | // Returns 0 if the kernel buffer is empty, 1 if the buffer is full. |
---|
| 225 | ////////////////////////////////////////////////////////////////////////////// |
---|
[165] | 226 | unsigned int _tty_read_irq( char *buffer, |
---|
| 227 | unsigned int length) |
---|
[158] | 228 | { |
---|
| 229 | unsigned int proc_id; |
---|
| 230 | unsigned int task_id; |
---|
| 231 | unsigned int tty_id; |
---|
| 232 | unsigned int ret; |
---|
| 233 | |
---|
| 234 | proc_id = _procid(); |
---|
| 235 | task_id = _scheduler[proc_id].current; |
---|
| 236 | tty_id = _scheduler[proc_id].context[task_id][CTX_TTY_ID]; |
---|
| 237 | |
---|
| 238 | if (_tty_get_full[tty_id] == 0) |
---|
| 239 | { |
---|
| 240 | ret = 0; |
---|
| 241 | } |
---|
| 242 | else |
---|
| 243 | { |
---|
| 244 | *buffer = _tty_get_buf[tty_id]; |
---|
| 245 | _tty_get_full[tty_id] = 0; |
---|
| 246 | ret = 1; |
---|
| 247 | } |
---|
| 248 | return ret; |
---|
| 249 | } |
---|
| 250 | |
---|
| 251 | //////////////////////////////////////////////////////////////////////////////// |
---|
| 252 | // _tty_read() |
---|
| 253 | // |
---|
| 254 | // This non-blocking function fetches one character directly from the TTY_READ |
---|
| 255 | // register of the TTY controler, and writes this character to the user buffer. |
---|
| 256 | // It doesn't use the TTY_GET_IRQ interrupt and the associated kernel buffer. |
---|
| 257 | // Returns 0 if the register is empty, 1 if the register is full. |
---|
| 258 | //////////////////////////////////////////////////////////////////////////////// |
---|
[165] | 259 | unsigned int _tty_read( char *buffer, |
---|
| 260 | unsigned int length) |
---|
[158] | 261 | { |
---|
| 262 | volatile unsigned int *tty_address; |
---|
| 263 | |
---|
| 264 | unsigned int proc_id; |
---|
| 265 | unsigned int task_id; |
---|
| 266 | unsigned int tty_id; |
---|
| 267 | |
---|
| 268 | proc_id = _procid(); |
---|
| 269 | task_id = _scheduler[proc_id].current; |
---|
| 270 | tty_id = _scheduler[proc_id].context[task_id][CTX_TTY_ID]; |
---|
| 271 | |
---|
| 272 | tty_address = (unsigned int*)&seg_tty_base + tty_id*TTY_SPAN; |
---|
| 273 | |
---|
| 274 | if ((tty_address[TTY_STATUS] & 0x1) != 0x1) return 0; |
---|
| 275 | |
---|
| 276 | *buffer = (char)tty_address[TTY_READ]; |
---|
| 277 | return 1; |
---|
| 278 | } |
---|
| 279 | |
---|
| 280 | //////////////////////////////////////////////////////////////////////////////// |
---|
| 281 | // VciMultiIcu driver |
---|
| 282 | //////////////////////////////////////////////////////////////////////////////// |
---|
| 283 | // There is in principle one MULTI-ICU component per cluster, and the |
---|
| 284 | // number of independant ICUs is equal to NB_PROCS, because there is |
---|
| 285 | // one ICU per processor. |
---|
| 286 | //////////////////////////////////////////////////////////////////////////////// |
---|
| 287 | |
---|
| 288 | //////////////////////////////////////////////////////////////////////////////// |
---|
| 289 | // _icu_write() |
---|
| 290 | // |
---|
[165] | 291 | // Write a 32-bit word in a memory mapped register of the MULTI_ICU device, |
---|
| 292 | // identified by the cluster index, and a processor local index. |
---|
[158] | 293 | // Returns 0 if success, > 0 if error. |
---|
| 294 | //////////////////////////////////////////////////////////////////////////////// |
---|
[165] | 295 | unsigned int _icu_write( unsigned int cluster_index, |
---|
| 296 | unsigned int proc_index, |
---|
| 297 | unsigned int register_index, |
---|
| 298 | unsigned int value ) |
---|
[158] | 299 | { |
---|
[165] | 300 | unsigned int *icu_address; |
---|
[158] | 301 | |
---|
[165] | 302 | // parameters checking |
---|
| 303 | if ( register_index >= ICU_SPAN) return 1; |
---|
| 304 | if ( cluster_index >= NB_CLUSTERS) return 1; |
---|
| 305 | if ( proc_index >= NB_PROCS ) return 1; |
---|
[158] | 306 | |
---|
[165] | 307 | icu_address = (unsigned int*)&seg_icu_base + |
---|
| 308 | ( cluster_index * CLUSTER_SPAN ) + |
---|
| 309 | ( proc_index * ICU_SPAN ); |
---|
| 310 | |
---|
| 311 | icu_address[register_index] = value; // write word |
---|
[158] | 312 | return 0; |
---|
| 313 | } |
---|
| 314 | |
---|
| 315 | //////////////////////////////////////////////////////////////////////////////// |
---|
| 316 | // _icu_read() |
---|
| 317 | // |
---|
[165] | 318 | // Read a 32-bit word in a memory mapped register of the MULTI_ICU device, |
---|
| 319 | // identified by the cluster index and a processor local index. |
---|
[158] | 320 | // Returns 0 if success, > 0 if error. |
---|
| 321 | //////////////////////////////////////////////////////////////////////////////// |
---|
[165] | 322 | unsigned int _icu_read( unsigned int cluster_index, |
---|
| 323 | unsigned int proc_index, |
---|
| 324 | unsigned int register_index, |
---|
| 325 | unsigned int* buffer ) |
---|
[158] | 326 | { |
---|
[165] | 327 | unsigned int *icu_address; |
---|
[158] | 328 | |
---|
[165] | 329 | // parameters checking |
---|
| 330 | if ( register_index >= ICU_SPAN) return 1; |
---|
| 331 | if ( cluster_index >= NB_CLUSTERS) return 1; |
---|
| 332 | if ( proc_index >= NB_PROCS ) return 1; |
---|
[158] | 333 | |
---|
[165] | 334 | icu_address = (unsigned int*)&seg_icu_base + |
---|
| 335 | ( cluster_index * CLUSTER_SPAN ) + |
---|
| 336 | ( proc_index * ICU_SPAN ); |
---|
| 337 | |
---|
| 338 | *buffer = icu_address[register_index]; // read word |
---|
[158] | 339 | return 0; |
---|
| 340 | } |
---|
| 341 | |
---|
| 342 | //////////////////////////////////////////////////////////////////////////////// |
---|
| 343 | // VciGcd driver |
---|
| 344 | //////////////////////////////////////////////////////////////////////////////// |
---|
| 345 | // The Greater Dommon Divider is a -very- simple hardware coprocessor |
---|
[165] | 346 | // performing the computation of the GCD of two 32 bits integers. |
---|
[158] | 347 | // It has no DMA capability. |
---|
| 348 | //////////////////////////////////////////////////////////////////////////////// |
---|
| 349 | |
---|
| 350 | //////////////////////////////////////////////////////////////////////////////// |
---|
| 351 | // _gcd_write() |
---|
| 352 | // |
---|
| 353 | // Write a 32-bit word in a memory mapped register of the GCD coprocessor. |
---|
| 354 | // Returns 0 if success, > 0 if error. |
---|
| 355 | //////////////////////////////////////////////////////////////////////////////// |
---|
[165] | 356 | unsigned int _gcd_write( unsigned int register_index, |
---|
| 357 | unsigned int value) |
---|
[158] | 358 | { |
---|
| 359 | volatile unsigned int *gcd_address; |
---|
| 360 | |
---|
[165] | 361 | // parameters checking |
---|
[158] | 362 | if (register_index >= GCD_END) |
---|
| 363 | return 1; |
---|
| 364 | |
---|
| 365 | gcd_address = (unsigned int*)&seg_gcd_base; |
---|
[165] | 366 | |
---|
| 367 | gcd_address[register_index] = value; // write word |
---|
[158] | 368 | return 0; |
---|
| 369 | } |
---|
| 370 | |
---|
| 371 | //////////////////////////////////////////////////////////////////////////////// |
---|
| 372 | // _gcd_read() |
---|
| 373 | // |
---|
| 374 | // Read a 32-bit word in a memory mapped register of the GCD coprocessor. |
---|
| 375 | // Returns 0 if success, > 0 if error. |
---|
| 376 | //////////////////////////////////////////////////////////////////////////////// |
---|
[165] | 377 | unsigned int _gcd_read( unsigned int register_index, |
---|
| 378 | unsigned int *buffer) |
---|
[158] | 379 | { |
---|
| 380 | volatile unsigned int *gcd_address; |
---|
| 381 | |
---|
[165] | 382 | // parameters checking |
---|
[158] | 383 | if (register_index >= GCD_END) |
---|
| 384 | return 1; |
---|
| 385 | |
---|
| 386 | gcd_address = (unsigned int*)&seg_gcd_base; |
---|
[165] | 387 | |
---|
| 388 | *buffer = gcd_address[register_index]; // read word |
---|
[158] | 389 | return 0; |
---|
| 390 | } |
---|
| 391 | |
---|
| 392 | //////////////////////////////////////////////////////////////////////////////// |
---|
| 393 | // VciBlockDevice driver |
---|
| 394 | //////////////////////////////////////////////////////////////////////////////// |
---|
[165] | 395 | // The VciBlockDevice is a single channel external storage contrÃŽler. |
---|
[158] | 396 | // The three functions below use the three variables _ioc_lock _ioc_done, and |
---|
[165] | 397 | // _ioc_status for synchronisation. |
---|
[158] | 398 | // As the IOC component can be used by several programs running in parallel, |
---|
| 399 | // the _ioc_lock variable guaranties exclusive access to the device. The |
---|
| 400 | // _ioc_read() and _ioc_write() functions use atomic LL/SC to get the lock. |
---|
| 401 | // and set _ioc_lock to a non zero value. The _ioc_write() and _ioc_read() |
---|
| 402 | // functions are blocking, polling the _ioc_lock variable until the device is |
---|
| 403 | // available. |
---|
| 404 | // When the tranfer is completed, the ISR routine activated by the IOC IRQ |
---|
| 405 | // set the _ioc_done variable to a non-zero value. Possible address errors |
---|
| 406 | // detected by the IOC peripheral are reported by the ISR in the _ioc_status |
---|
| 407 | // variable. |
---|
| 408 | // The _ioc_completed() function is polling the _ioc_done variable, waiting for |
---|
| 409 | // tranfer conpletion. When the completion is signaled, the _ioc_completed() |
---|
| 410 | // function reset the _ioc_done variable to zero, and releases the _ioc_lock |
---|
| 411 | // variable. |
---|
| 412 | // |
---|
| 413 | // In a multi-processing environment, this polling policy should be replaced by |
---|
| 414 | // a descheduling policy for the requesting process. |
---|
| 415 | /////////////////////////////////////////////////////////////////////////////// |
---|
| 416 | |
---|
| 417 | /////////////////////////////////////////////////////////////////////////////// |
---|
| 418 | // _ioc_get_lock() |
---|
| 419 | // |
---|
| 420 | // This blocking helper is used by '_ioc_read()' and '_ioc_write()' functions |
---|
| 421 | // to get _ioc_lock using atomic LL/SC. |
---|
| 422 | /////////////////////////////////////////////////////////////////////////////// |
---|
| 423 | static inline void _ioc_get_lock() |
---|
| 424 | { |
---|
| 425 | register unsigned int delay = (_proctime() & 0xF) << 4; |
---|
| 426 | register unsigned int *plock = (unsigned int*)&_ioc_lock; |
---|
| 427 | |
---|
| 428 | asm volatile ( |
---|
| 429 | "_ioc_llsc: \n" |
---|
| 430 | "ll $2, 0(%0) \n" /* $2 <= _ioc_lock current value */ |
---|
| 431 | "bnez $2, _ioc_delay \n" /* delay if _ioc_lock already taken */ |
---|
| 432 | "li $3, 1 \n" /* $3 <= argument for sc */ |
---|
| 433 | "sc $3, 0(%0) \n" /* try to set _ioc_lock */ |
---|
| 434 | "bnez $3, _ioc_ok \n" /* exit if atomic */ |
---|
| 435 | "_ioc_delay: \n" |
---|
| 436 | "move $4, %1 \n" /* $4 <= delay */ |
---|
| 437 | "_ioc_loop: \n" |
---|
[165] | 438 | "beqz $4, _ioc_loop \n" /* test end delay */ |
---|
[158] | 439 | "addi $4, $4, -1 \n" /* $4 <= $4 - 1 */ |
---|
[165] | 440 | "j _ioc_llsc \n" /* retry ll */ |
---|
| 441 | "nop \n" |
---|
[158] | 442 | "_ioc_ok: \n" |
---|
| 443 | : |
---|
| 444 | :"r"(plock), "r"(delay) |
---|
| 445 | :"$2", "$3", "$4"); |
---|
| 446 | } |
---|
| 447 | |
---|
| 448 | /////////////////////////////////////////////////////////////////////////////// |
---|
| 449 | // _ioc_write() |
---|
| 450 | // |
---|
| 451 | // Transfer data from a memory buffer to a file on the block_device. |
---|
| 452 | // The source memory buffer must be in user address space. |
---|
| 453 | // - lba : first block index on the disk. |
---|
| 454 | // - buffer : base address of the memory buffer. |
---|
| 455 | // - count : number of blocks to be transfered. |
---|
| 456 | // Returns 0 if success, > 0 if error. |
---|
| 457 | /////////////////////////////////////////////////////////////////////////////// |
---|
| 458 | unsigned int _ioc_write( unsigned int lba, |
---|
| 459 | const void* buffer, |
---|
| 460 | unsigned int count) |
---|
| 461 | { |
---|
| 462 | volatile unsigned int *ioc_address; |
---|
| 463 | |
---|
| 464 | ioc_address = (unsigned int*)&seg_ioc_base; |
---|
| 465 | |
---|
| 466 | /* buffer must be in user space */ |
---|
| 467 | unsigned int block_size = ioc_address[BLOCK_DEVICE_BLOCK_SIZE]; |
---|
| 468 | |
---|
| 469 | if (((unsigned int)buffer >= 0x80000000) |
---|
| 470 | || (((unsigned int)buffer + block_size*count) >= 0x80000000)) |
---|
| 471 | return 1; |
---|
| 472 | |
---|
| 473 | /* get the lock on ioc device */ |
---|
| 474 | _ioc_get_lock(); |
---|
| 475 | |
---|
| 476 | /* block_device configuration for the write transfer */ |
---|
| 477 | ioc_address[BLOCK_DEVICE_BUFFER] = (unsigned int)buffer; |
---|
| 478 | ioc_address[BLOCK_DEVICE_COUNT] = count; |
---|
| 479 | ioc_address[BLOCK_DEVICE_LBA] = lba; |
---|
| 480 | ioc_address[BLOCK_DEVICE_IRQ_ENABLE] = 1; |
---|
| 481 | ioc_address[BLOCK_DEVICE_OP] = BLOCK_DEVICE_WRITE; |
---|
| 482 | |
---|
| 483 | return 0; |
---|
| 484 | } |
---|
| 485 | |
---|
| 486 | /////////////////////////////////////////////////////////////////////////////// |
---|
| 487 | // _ioc_read() |
---|
| 488 | // |
---|
| 489 | // Transfer data from a file on the block device to a memory buffer. |
---|
| 490 | // The destination memory buffer must be in user address space. |
---|
| 491 | // - lba : first block index on the disk. |
---|
| 492 | // - buffer : base address of the memory buffer. |
---|
| 493 | // - count : number of blocks to be transfered. |
---|
| 494 | // All cache lines corresponding to the the target buffer are invalidated |
---|
| 495 | // for cache coherence. |
---|
| 496 | // Returns 0 if success, > 0 if error. |
---|
| 497 | /////////////////////////////////////////////////////////////////////////////// |
---|
| 498 | unsigned int _ioc_read( unsigned int lba, |
---|
| 499 | void* buffer, |
---|
| 500 | unsigned int count ) |
---|
| 501 | { |
---|
| 502 | volatile unsigned int *ioc_address; |
---|
| 503 | |
---|
| 504 | ioc_address = (unsigned int*)&seg_ioc_base; |
---|
| 505 | |
---|
| 506 | /* buffer must be in user space */ |
---|
| 507 | unsigned int block_size = ioc_address[BLOCK_DEVICE_BLOCK_SIZE]; |
---|
| 508 | |
---|
| 509 | if (((unsigned int)buffer >= 0x80000000) |
---|
| 510 | || (((unsigned int)buffer + block_size*count) >= 0x80000000)) |
---|
| 511 | return 1; |
---|
| 512 | |
---|
| 513 | /* get the lock on ioc device */ |
---|
| 514 | _ioc_get_lock(); |
---|
| 515 | |
---|
| 516 | /* block_device configuration for the read transfer */ |
---|
| 517 | ioc_address[BLOCK_DEVICE_BUFFER] = (unsigned int)buffer; |
---|
| 518 | ioc_address[BLOCK_DEVICE_COUNT] = count; |
---|
| 519 | ioc_address[BLOCK_DEVICE_LBA] = lba; |
---|
| 520 | ioc_address[BLOCK_DEVICE_IRQ_ENABLE] = 1; |
---|
| 521 | ioc_address[BLOCK_DEVICE_OP] = BLOCK_DEVICE_READ; |
---|
| 522 | |
---|
| 523 | /* invalidation of data cache */ |
---|
| 524 | _dcache_buf_invalidate(buffer, block_size*count); |
---|
| 525 | |
---|
| 526 | return 0; |
---|
| 527 | } |
---|
| 528 | |
---|
| 529 | ///////////////////////////////////////////////////////////////////////////////// |
---|
| 530 | // _ioc_completed() |
---|
| 531 | // |
---|
| 532 | // This function checks completion of an I/O transfer and reports errors. |
---|
| 533 | // As it is a blocking call, the processor is stalled until the next interrupt. |
---|
| 534 | // Returns 0 if success, > 0 if error. |
---|
| 535 | ///////////////////////////////////////////////////////////////////////////////// |
---|
| 536 | unsigned int _ioc_completed() |
---|
| 537 | { |
---|
| 538 | unsigned int ret; |
---|
| 539 | |
---|
| 540 | /* busy waiting */ |
---|
| 541 | while (_ioc_done == 0) |
---|
| 542 | asm volatile("nop"); |
---|
| 543 | |
---|
| 544 | /* test IOC status */ |
---|
| 545 | if ((_ioc_status != BLOCK_DEVICE_READ_SUCCESS) |
---|
| 546 | && (_ioc_status != BLOCK_DEVICE_WRITE_SUCCESS)) ret = 1; /* error */ |
---|
| 547 | else ret = 0; /* success */ |
---|
| 548 | |
---|
| 549 | /* reset synchronization variables */ |
---|
| 550 | _ioc_lock =0; |
---|
| 551 | _ioc_done =0; |
---|
| 552 | |
---|
| 553 | return ret; |
---|
| 554 | } |
---|
| 555 | |
---|
| 556 | ////////////////////////////////////////////////////////////////////////////////// |
---|
| 557 | // VciFrameBuffer driver |
---|
| 558 | ////////////////////////////////////////////////////////////////////////////////// |
---|
| 559 | // The '_fb_sync_write' and '_fb_sync_read' functions use a memcpy strategy to |
---|
| 560 | // implement the transfer between a data buffer (user space) and the frame |
---|
| 561 | // buffer (kernel space). They are blocking until completion of the transfer. |
---|
| 562 | // The '_fb_write()', '_fb_read()' and '_fb_completed()' functions use the DMA |
---|
| 563 | // coprocessor to transfer data between the user buffer and the frame buffer. |
---|
| 564 | // These functions use a polling policy to test the global variables _dma_busy[i] |
---|
| 565 | // and detect the transfer completion. |
---|
| 566 | // There is NB_PROCS DMA channels, that are indexed by the proc_id. |
---|
| 567 | // The _dma_busy[i] synchronisation variables (one per channel) are set by the OS, |
---|
| 568 | // and reset by the ISR. |
---|
| 569 | ////////////////////////////////////////////////////////////////////////////////// |
---|
| 570 | |
---|
| 571 | ////////////////////////////////////////////////////////////////////////////////// |
---|
| 572 | // _fb_sync_write() |
---|
| 573 | // Transfer data from an memory buffer to the frame_buffer device using |
---|
| 574 | // a memcpy. The source memory buffer must be in user address space. |
---|
| 575 | // - offset : offset (in bytes) in the frame buffer. |
---|
| 576 | // - buffer : base address of the memory buffer. |
---|
| 577 | // - length : number of bytes to be transfered. |
---|
| 578 | // Returns 0 if success, > 0 if error. |
---|
| 579 | ////////////////////////////////////////////////////////////////////////////////// |
---|
| 580 | unsigned int _fb_sync_write( unsigned int offset, |
---|
| 581 | const void* buffer, |
---|
| 582 | unsigned int length ) |
---|
| 583 | { |
---|
| 584 | volatile unsigned char *fb_address; |
---|
| 585 | |
---|
| 586 | /* buffer must be in user space */ |
---|
| 587 | if (((unsigned int)buffer >= 0x80000000) |
---|
| 588 | || (((unsigned int)buffer + length ) >= 0x80000000 )) |
---|
| 589 | return 1; |
---|
| 590 | |
---|
| 591 | fb_address = (unsigned char*)&seg_fb_base + offset; |
---|
| 592 | |
---|
| 593 | /* buffer copy */ |
---|
| 594 | memcpy((void*)fb_address, (void*)buffer, length); |
---|
| 595 | |
---|
| 596 | return 0; |
---|
| 597 | } |
---|
| 598 | |
---|
| 599 | ////////////////////////////////////////////////////////////////////////////////// |
---|
| 600 | // _fb_sync_read() |
---|
| 601 | // Transfer data from the frame_buffer device to a memory buffer using |
---|
| 602 | // a memcpy. The destination memory buffer must be in user address space. |
---|
| 603 | // - offset : offset (in bytes) in the frame buffer. |
---|
| 604 | // - buffer : base address of the memory buffer. |
---|
| 605 | // - length : number of bytes to be transfered. |
---|
| 606 | // Returns 0 if success, > 0 if error. |
---|
| 607 | ////////////////////////////////////////////////////////////////////////////////// |
---|
| 608 | unsigned int _fb_sync_read( unsigned int offset, |
---|
| 609 | const void* buffer, |
---|
| 610 | unsigned int length ) |
---|
| 611 | { |
---|
| 612 | volatile unsigned char *fb_address; |
---|
| 613 | |
---|
| 614 | /* parameters checking */ |
---|
| 615 | /* buffer must be in user space */ |
---|
| 616 | if (((unsigned int)buffer >= 0x80000000) |
---|
| 617 | || (((unsigned int)buffer + length ) >= 0x80000000 )) |
---|
| 618 | return 1; |
---|
| 619 | |
---|
| 620 | fb_address = (unsigned char*)&seg_fb_base + offset; |
---|
| 621 | |
---|
| 622 | /* buffer copy */ |
---|
| 623 | memcpy((void*)buffer, (void*)fb_address, length); |
---|
| 624 | |
---|
| 625 | return 0; |
---|
| 626 | } |
---|
| 627 | |
---|
| 628 | ////////////////////////////////////////////////////////////////////////////////// |
---|
| 629 | // _fb_write() |
---|
| 630 | // Transfer data from an memory buffer to the frame_buffer device using a DMA. |
---|
| 631 | // The source memory buffer must be in user address space. |
---|
| 632 | // - offset : offset (in bytes) in the frame buffer. |
---|
| 633 | // - buffer : base address of the memory buffer. |
---|
| 634 | // - length : number of bytes to be transfered. |
---|
| 635 | // Returns 0 if success, > 0 if error. |
---|
| 636 | ////////////////////////////////////////////////////////////////////////////////// |
---|
| 637 | unsigned int _fb_write( unsigned int offset, |
---|
| 638 | const void* buffer, |
---|
| 639 | unsigned int length ) |
---|
| 640 | { |
---|
| 641 | volatile unsigned char *fb_address; |
---|
| 642 | volatile unsigned int *dma; |
---|
| 643 | |
---|
| 644 | unsigned int proc_id; |
---|
| 645 | unsigned int delay; |
---|
| 646 | unsigned int i; |
---|
| 647 | |
---|
| 648 | /* buffer must be in user space */ |
---|
| 649 | if (((unsigned int)buffer >= 0x80000000) |
---|
| 650 | || (((unsigned int)buffer + length ) >= 0x80000000 )) |
---|
| 651 | return 1; |
---|
| 652 | |
---|
| 653 | proc_id = _procid(); |
---|
| 654 | fb_address = (unsigned char*)&seg_fb_base + offset; |
---|
| 655 | dma = (unsigned int*)&seg_dma_base + (proc_id * DMA_SPAN); |
---|
| 656 | |
---|
| 657 | /* waiting until DMA device is available */ |
---|
| 658 | while (_dma_busy[proc_id] != 0) |
---|
| 659 | { |
---|
| 660 | /* if the lock failed, busy wait with a pseudo random delay between bus |
---|
| 661 | * accesses */ |
---|
| 662 | delay = (_proctime() & 0xF) << 4; |
---|
| 663 | for (i = 0; i < delay; i++) |
---|
| 664 | asm volatile("nop"); |
---|
| 665 | } |
---|
| 666 | _dma_busy[proc_id] = 1; |
---|
| 667 | |
---|
| 668 | /* DMA configuration for write transfer */ |
---|
| 669 | dma[DMA_IRQ_DISABLE] = 0; |
---|
| 670 | dma[DMA_SRC] = (unsigned int)buffer; |
---|
| 671 | dma[DMA_DST] = (unsigned int)fb_address; |
---|
| 672 | dma[DMA_LEN] = (unsigned int)length; |
---|
| 673 | return 0; |
---|
| 674 | } |
---|
| 675 | |
---|
| 676 | ////////////////////////////////////////////////////////////////////////////////// |
---|
| 677 | // _fb_read() |
---|
| 678 | // Transfer data from the frame_buffer device to an memory buffer using a DMA. |
---|
| 679 | // The destination memory buffer must be in user address space. |
---|
| 680 | // - offset : offset (in bytes) in the frame buffer. |
---|
| 681 | // - buffer : base address of the memory buffer. |
---|
| 682 | // - length : number of bytes to be transfered. |
---|
| 683 | // All cache lines corresponding to the the target buffer are invalidated |
---|
| 684 | // for cache coherence. |
---|
| 685 | // Returns 0 if success, > 0 if error. |
---|
| 686 | ////////////////////////////////////////////////////////////////////////////////// |
---|
| 687 | unsigned int _fb_read( unsigned int offset, |
---|
| 688 | const void* buffer, |
---|
| 689 | unsigned int length ) |
---|
| 690 | { |
---|
| 691 | volatile unsigned char *fb_address; |
---|
| 692 | volatile unsigned int *dma; |
---|
| 693 | |
---|
| 694 | unsigned int proc_id; |
---|
| 695 | unsigned int delay; |
---|
| 696 | unsigned int i; |
---|
| 697 | |
---|
| 698 | /* buffer must be in user space */ |
---|
| 699 | if (((unsigned int)buffer >= 0x80000000) |
---|
| 700 | || (((unsigned int)buffer + length ) >= 0x80000000 )) |
---|
| 701 | return 1; |
---|
| 702 | |
---|
| 703 | proc_id = _procid(); |
---|
| 704 | fb_address = (unsigned char*)&seg_fb_base + offset; |
---|
| 705 | dma = (unsigned int*)&seg_dma_base + (proc_id * DMA_SPAN); |
---|
| 706 | |
---|
| 707 | /* waiting until DMA device is available */ |
---|
| 708 | while (_dma_busy[proc_id] != 0) |
---|
| 709 | { |
---|
| 710 | /* if the lock failed, busy wait with a pseudo random delay between bus |
---|
| 711 | * accesses */ |
---|
| 712 | delay = (_proctime() & 0xF) << 4; |
---|
| 713 | for (i = 0; i < delay; i++) |
---|
| 714 | asm volatile("nop"); |
---|
| 715 | } |
---|
| 716 | _dma_busy[proc_id] = 1; |
---|
| 717 | |
---|
| 718 | /* DMA configuration for write transfer */ |
---|
| 719 | dma[DMA_IRQ_DISABLE] = 0; |
---|
| 720 | dma[DMA_SRC] = (unsigned int)fb_address; |
---|
| 721 | dma[DMA_DST] = (unsigned int)buffer; |
---|
| 722 | dma[DMA_LEN] = (unsigned int)length; |
---|
| 723 | |
---|
| 724 | /* invalidation of data cache */ |
---|
| 725 | _dcache_buf_invalidate(buffer, length); |
---|
| 726 | |
---|
| 727 | return 0; |
---|
| 728 | } |
---|
| 729 | |
---|
| 730 | ////////////////////////////////////////////////////////////////////////////////// |
---|
| 731 | // _fb_completed() |
---|
| 732 | // This function checks completion of a DMA transfer to or fom the frame buffer. |
---|
| 733 | // As it is a blocking call, the processor is stalled until the next interrupt. |
---|
| 734 | // Returns 0 if success, > 0 if error. |
---|
| 735 | ////////////////////////////////////////////////////////////////////////////////// |
---|
| 736 | unsigned int _fb_completed() |
---|
| 737 | { |
---|
| 738 | unsigned int proc_id; |
---|
| 739 | |
---|
| 740 | proc_id = _procid(); |
---|
| 741 | |
---|
| 742 | while (_dma_busy[proc_id] != 0) |
---|
| 743 | asm volatile("nop"); |
---|
| 744 | |
---|
| 745 | if (_dma_status[proc_id] != 0) |
---|
| 746 | return 1; |
---|
| 747 | |
---|
| 748 | return 0; |
---|
| 749 | } |
---|
| 750 | |
---|