chcore.h 17.9 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485
/*
    ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
                 2011,2012 Giovanni Di Sirio.

    This file is part of ChibiOS/RT.

    ChibiOS/RT 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 3 of the License, or
    (at your option) any later version.

    ChibiOS/RT is distributed in 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, see <http://www.gnu.org/licenses/>.

                                      ---

    A special exception to the GPL can be applied should you wish to distribute
    a combined work that includes ChibiOS/RT, without being obliged to provide
    the source code for any proprietary components. See the file exception.txt
    for full details of how and when the exception can be applied.
*/

/**
 * @file    ARM/chcore.h
 * @brief   ARM7/9 architecture port macros and structures.
 *
 * @addtogroup ARM_CORE
 * @{
 */

#ifndef _CHCORE_H_
#define _CHCORE_H_

/*===========================================================================*/
/* Port constants.                                                           */
/*===========================================================================*/

/* Core variants identifiers.*/
#define ARM_CORE_ARM7TDMI           7   /**< ARM77TDMI core identifier.     */
#define ARM_CORE_ARM9               9   /**< ARM9 core identifier.          */

/* Inclusion of the ARM implementation specific parameters.*/
#include "armparams.h"

/* ARM core check, only ARM7TDMI and ARM9 supported right now.*/
#if (ARM_CORE == ARM_CORE_ARM7TDMI) || (ARM_CORE == ARM_CORE_ARM9)
#else
#error "unknown or unsupported ARM core"
#endif

/*===========================================================================*/
/* Port statically derived parameters.                                       */
/*===========================================================================*/

/*===========================================================================*/
/* Port macros.                                                              */
/*===========================================================================*/

/*===========================================================================*/
/* Port configurable parameters.                                             */
/*===========================================================================*/

/**
 * @brief   If enabled allows the idle thread to enter a low power mode.
 */
#ifndef ARM_ENABLE_WFI_IDLE
#define ARM_ENABLE_WFI_IDLE             FALSE
#endif

/*===========================================================================*/
/* Port exported info.                                                       */
/*===========================================================================*/

/**
 * @brief   Macro defining a generic ARM architecture.
 */
#define CH_ARCHITECTURE_ARM

#if defined(__DOXYGEN__)
/**
 * @brief   Macro defining the specific ARM architecture.
 * @note    This macro is for documentation only, the real name changes
 *          depending on the selected architecture, the possible names are:
 *          - CH_ARCHITECTURE_ARM7TDMI.
 *          - CH_ARCHITECTURE_ARM9.
 *          .
 */
#define CH_ARCHITECTURE_ARMx

/**
 * @brief   Name of the implemented architecture.
 * @note    The value is for documentation only, the real value changes
 *          depending on the selected architecture, the possible values are:
 *          - "ARM7".
 *          - "ARM9".
 *          .
 */
#define CH_ARCHITECTURE_NAME            "ARMx"

/**
 * @brief   Name of the architecture variant (optional).
 * @note    The value is for documentation only, the real value changes
 *          depending on the selected architecture, the possible values are:
 *          - "ARM7TDMI"
 *          - "ARM9"
 *          .
 */
#define CH_CORE_VARIANT_NAME            "ARMxy"

/**
 * @brief   Port-specific information string.
 * @note    The value is for documentation only, the real value changes
 *          depending on the selected options, the possible values are:
 *          - "Pure ARM"
 *          - "Pure THUMB"
 *          - "Interworking"
 *          .
 */
#define CH_PORT_INFO                    "ARM|THUMB|Interworking"

#elif ARM_CORE == ARM_CORE_ARM7TDMI
#define CH_ARCHITECTURE_ARM7TDMI
#define CH_ARCHITECTURE_NAME            "ARM7"
#define CH_CORE_VARIANT_NAME            "ARM7TDMI"

#elif ARM_MODEL == ARM_VARIANT_ARM9
#define CH_ARCHITECTURE_ARM9
#define CH_ARCHITECTURE_NAME            "ARM9"
#define CH_CORE_VARIANT_NAME            "ARM9"
#endif

#if THUMB_PRESENT
#if THUMB_NO_INTERWORKING
#define CH_PORT_INFO                    "Pure THUMB mode"
#else /* !THUMB_NO_INTERWORKING */
#define CH_PORT_INFO                    "Interworking mode"
#endif /* !THUMB_NO_INTERWORKING */
#else /* !THUMB_PRESENT */
#define CH_PORT_INFO                    "Pure ARM mode"
#endif /* !THUMB_PRESENT */

/**
 * @brief   Name of the compiler supported by this port.
 */
#define CH_COMPILER_NAME                "GCC " __VERSION__

/*===========================================================================*/
/* Port implementation part (common).                                        */
/*===========================================================================*/

/**
 * @brief   32 bits stack and memory alignment enforcement.
 */
typedef uint32_t stkalign_t;

/**
 * @brief   Generic ARM register.
 */
typedef void *regarm_t;

/**
 * @brief   Interrupt saved context.
 * @details This structure represents the stack frame saved during a
 *          preemption-capable interrupt handler.
 */
struct extctx {
  regarm_t      spsr_irq;
  regarm_t      lr_irq;
  regarm_t      r0;
  regarm_t      r1;
  regarm_t      r2;
  regarm_t      r3;
  regarm_t      r12;
  regarm_t      lr_usr;
};

/**
 * @brief   System saved context.
 * @details This structure represents the inner stack frame during a context
 *          switching.
 */
struct intctx {
  regarm_t      r4;
  regarm_t      r5;
  regarm_t      r6;
  regarm_t      r7;
  regarm_t      r8;
  regarm_t      r9;
  regarm_t      r10;
  regarm_t      r11;
  regarm_t      lr;
};

/**
 * @brief   Platform dependent part of the @p Thread structure.
 * @details In this port the structure just holds a pointer to the @p intctx
 *          structure representing the stack pointer at context switch time.
 */
struct context {
  struct intctx *r13;
};

/**
 * @brief   Platform dependent part of the @p chThdCreateI() API.
 * @details This code usually setup the context switching frame represented
 *          by an @p intctx structure.
 */
#define SETUP_CONTEXT(workspace, wsize, pf, arg) {                          \
  tp->p_ctx.r13 = (struct intctx *)((uint8_t *)workspace +                  \
                                     wsize -                                \
                                     sizeof(struct intctx));                \
  tp->p_ctx.r13->r4 = pf;                                                   \
  tp->p_ctx.r13->r5 = arg;                                                  \
  tp->p_ctx.r13->lr = _port_thread_start;                                   \
}

/**
 * @brief   Stack size for the system idle thread.
 * @details This size depends on the idle thread implementation, usually
 *          the idle thread should take no more space than those reserved
 *          by @p PORT_INT_REQUIRED_STACK.
 * @note    In this port it is set to 4 because the idle thread does have
 *          a stack frame when compiling without optimizations.
 */
#ifndef PORT_IDLE_THREAD_STACK_SIZE
#define PORT_IDLE_THREAD_STACK_SIZE     4
#endif

/**
 * @brief   Per-thread stack overhead for interrupts servicing.
 * @details This constant is used in the calculation of the correct working
 *          area size.
 *          This value can be zero on those architecture where there is a
 *          separate interrupt stack and the stack space between @p intctx and
 *          @p extctx is known to be zero.
 * @note    In this port 0x10 is a safe value, it can be reduced after careful
 *          analysis of the generated code.
 */
#ifndef PORT_INT_REQUIRED_STACK
#define PORT_INT_REQUIRED_STACK         0x10
#endif

/**
 * @brief   Enforces a correct alignment for a stack area size value.
 */
#define STACK_ALIGN(n) ((((n) - 1) | (sizeof(stkalign_t) - 1)) + 1)

/**
 * @brief   Computes the thread working area global size.
 */
#define THD_WA_SIZE(n) STACK_ALIGN(sizeof(Thread) +                         \
                                   sizeof(struct intctx) +                  \
                                   sizeof(struct extctx) +                  \
                                   (n) + (PORT_INT_REQUIRED_STACK))

/**
 * @brief   Static working area allocation.
 * @details This macro is used to allocate a static thread working area
 *          aligned as both position and size.
 */
#define WORKING_AREA(s, n) stkalign_t s[THD_WA_SIZE(n) / sizeof(stkalign_t)]

/**
 * @brief   IRQ prologue code.
 * @details This macro must be inserted at the start of all IRQ handlers
 *          enabled to invoke system APIs.
 * @note    This macro has a different implementation depending if compiled in
 *          ARM or THUMB mode.
 * @note    The THUMB implementation starts with ARM code because interrupt
 *          vectors are always invoked in ARM mode regardless the bit 0
 *          value. The switch in THUMB mode is done in the function prologue so
 *          it is transparent to the user code.
 */
#if !defined(PORT_IRQ_PROLOGUE)
#ifdef THUMB
#define PORT_IRQ_PROLOGUE() {                                               \
  asm volatile (".code 32                               \n\t"               \
                "stmfd   sp!, {r0-r3, r12, lr}          \n\t"               \
                "add     r0, pc, #1                     \n\t"               \
                "bx      r0                             \n\t"               \
                ".code 16" : : : "memory");                                 \
}
#else /* !THUMB */
#define PORT_IRQ_PROLOGUE() {                                               \
  asm volatile ("stmfd    sp!, {r0-r3, r12, lr}" : : : "memory");           \
}
#endif /* !THUMB */
#endif /* !defined(PORT_IRQ_PROLOGUE) */

/**
 * @brief   IRQ epilogue code.
 * @details This macro must be inserted at the end of all IRQ handlers
 *          enabled to invoke system APIs.
 * @note    This macro has a different implementation depending if compiled in
 *          ARM or THUMB mode.
 */
#if !defined(PORT_IRQ_EPILOGUE)
#ifdef THUMB
#define PORT_IRQ_EPILOGUE() {                                               \
  asm volatile ("ldr     r0, =_port_irq_common          \n\t"               \
                "bx      r0" : : : "memory");                               \
}
#else /* !THUMB */
#define PORT_IRQ_EPILOGUE() {                                               \
  asm volatile ("b       _port_irq_common" : : : "memory");                 \
}
#endif /* !THUMB */
#endif /* !defined(PORT_IRQ_EPILOGUE) */

/**
 * @brief   IRQ handler function declaration.
 * @note    @p id can be a function name or a vector number depending on the
 *          port implementation.
 */
#if !defined(PORT_IRQ_HANDLER)
#define PORT_IRQ_HANDLER(id) __attribute__((naked)) void id(void)
#endif /* !defined(PORT_IRQ_HANDLER) */

/**
 * @brief   Fast IRQ handler function declaration.
 * @note    @p id can be a function name or a vector number depending on the
 *          port implementation.
 */
#if !defined(PORT_FAST_IRQ_HANDLER)
#define PORT_FAST_IRQ_HANDLER(id)                                           \
  __attribute__((interrupt("FIQ"))) void id(void)
#endif /* !defined(PORT_FAST_IRQ_HANDLER) */

/**
 * @brief   Port-related initialization code.
 * @note    This function is empty in this port.
 */
#define port_init()

/**
 * @brief   Kernel-lock action.
 * @details Usually this function just disables interrupts but may perform
 *          more actions.
 * @note    In this port it disables the IRQ sources and keeps FIQ sources
 *          enabled.
 */
#ifdef THUMB
#define port_lock() {                                                       \
  asm volatile ("bl     _port_lock_thumb" : : : "r3", "lr", "memory");      \
}
#else /* !THUMB */
#define port_lock() asm volatile ("msr     CPSR_c, #0x9F" : : : "memory")
#endif /* !THUMB */

/**
 * @brief   Kernel-unlock action.
 * @details Usually this function just enables interrupts but may perform
 *          more actions.
 * @note    In this port it enables both the IRQ and FIQ sources.
 */
#ifdef THUMB
#define port_unlock() {                                                     \
  asm volatile ("bl     _port_unlock_thumb" : : : "r3", "lr", "memory");    \
}
#else /* !THUMB */
#define port_unlock() asm volatile ("msr     CPSR_c, #0x1F" : : : "memory")
#endif /* !THUMB */

/**
 * @brief   Kernel-lock action from an interrupt handler.
 * @details This function is invoked before invoking I-class APIs from
 *          interrupt handlers. The implementation is architecture dependent,
 *          in its simplest form it is void.
 * @note    Empty in this port.
 */
#define port_lock_from_isr()

/**
 * @brief   Kernel-unlock action from an interrupt handler.
 * @details This function is invoked after invoking I-class APIs from interrupt
 *          handlers. The implementation is architecture dependent, in its
 *          simplest form it is void.
 * @note    Empty in this port.
 */
#define port_unlock_from_isr()

/**
 * @brief   Disables all the interrupt sources.
 * @note    Of course non-maskable interrupt sources are not included.
 * @note    In this port it disables both the IRQ and FIQ sources.
 * @note    Implements a workaround for spurious interrupts taken from the NXP
 *          LPC214x datasheet.
 */
#ifdef THUMB
#define port_disable() {                                                    \
  asm volatile ("bl     _port_disable_thumb" : : : "r3", "lr", "memory");   \
}
#else /* !THUMB */
#define port_disable() {                                                    \
  asm volatile ("mrs     r3, CPSR                       \n\t"               \
                "orr     r3, #0x80                      \n\t"               \
                "msr     CPSR_c, r3                     \n\t"               \
                "orr     r3, #0x40                      \n\t"               \
                "msr     CPSR_c, r3" : : : "r3", "memory");                 \
}
#endif /* !THUMB */

/**
 * @brief   Disables the interrupt sources below kernel-level priority.
 * @note    Interrupt sources above kernel level remains enabled.
 * @note    In this port it disables the IRQ sources and enables the
 *          FIQ sources.
 */
#ifdef THUMB
#define port_suspend() {                                                    \
  asm volatile ("bl     _port_suspend_thumb" : : : "r3", "lr", "memory");   \
}
#else /* !THUMB */
#define port_suspend() asm volatile ("msr     CPSR_c, #0x9F" : : : "memory")
#endif /* !THUMB */

/**
 * @brief   Enables all the interrupt sources.
 * @note    In this port it enables both the IRQ and FIQ sources.
 */
#ifdef THUMB
#define port_enable() {                                                     \
  asm volatile ("bl     _port_enable_thumb" : : : "r3", "lr", "memory");    \
}
#else /* !THUMB */
#define port_enable() asm volatile ("msr     CPSR_c, #0x1F" : : : "memory")
#endif /* !THUMB */

/**
 * @brief   Performs a context switch between two threads.
 * @details This is the most critical code in any port, this function
 *          is responsible for the context switch between 2 threads.
 * @note    The implementation of this code affects <b>directly</b> the context
 *          switch performance so optimize here as much as you can.
 * @note    Implemented as inlined code for performance reasons.
 *
 * @param[in] ntp       the thread to be switched in
 * @param[in] otp       the thread to be switched out
 */
#ifdef THUMB
#if CH_DBG_ENABLE_STACK_CHECK
#define port_switch(ntp, otp) {                                             \
  register struct intctx *r13 asm ("r13");                                  \
  if ((stkalign_t *)(r13 - 1) < otp->p_stklimit)                            \
    chDbgPanic("stack overflow");                                           \
  _port_switch_thumb(ntp, otp);                                             \
}
#else /* !CH_DBG_ENABLE_STACK_CHECK */
#define port_switch(ntp, otp) _port_switch_thumb(ntp, otp)
#endif /* !CH_DBG_ENABLE_STACK_CHECK */
#else /* !THUMB */
#if CH_DBG_ENABLE_STACK_CHECK
#define port_switch(ntp, otp) {                                             \
  register struct intctx *r13 asm ("r13");                                  \
  if ((stkalign_t *)(r13 - 1) < otp->p_stklimit)                            \
    chDbgPanic("stack overflow");                                           \
  _port_switch_arm(ntp, otp);                                               \
}
#else /* !CH_DBG_ENABLE_STACK_CHECK */
#define port_switch(ntp, otp) _port_switch_arm(ntp, otp)
#endif /* !CH_DBG_ENABLE_STACK_CHECK */
#endif /* !THUMB */

#ifdef __cplusplus
extern "C" {
#endif
  void port_halt(void);
#ifdef THUMB
  void _port_switch_thumb(Thread *ntp, Thread *otp);
#else /* !THUMB */
  void _port_switch_arm(Thread *ntp, Thread *otp);
#endif /* !THUMB */
  void _port_thread_start(void);
#ifdef __cplusplus
}
#endif

#endif /* _CHCORE_H_ */

/** @} */