LUFA/Common/Common.h

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2011.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6            www.lufa-lib.org
   7 */
   8
   9 /*
  10   Copyright 2011  Dean Camera (dean [at] fourwalledcubicle [dot] com)
  11
  12   Permission to use, copy, modify, distribute, and sell this
  13   software and its documentation for any purpose is hereby granted
  14   without fee, provided that the above copyright notice appear in
  15   all copies and that both that the copyright notice and this
  16   permission notice and warranty disclaimer appear in supporting
  17   documentation, and that the name of the author not be used in
  18   advertising or publicity pertaining to distribution of the
  19   software without specific, written prior permission.
  20
  21   The author disclaim all warranties with regard to this
  22   software, including all implied warranties of merchantability
  23   and fitness.  In no event shall the author be liable for any
  24   special, indirect or consequential damages or any damages
  25   whatsoever resulting from loss of use, data or profits, whether
  26   in an action of contract, negligence or other tortious action,
  27   arising out of or in connection with the use or performance of
  28   this software.
  29 */
  30
  31 /** \file
  32  *  \brief Common library convenience headers, macros and functions.
  33  *
  34  *  \copydetails Group_Common
  35  */
  36
  37 /** \defgroup Group_Common Common Utility Headers - LUFA/Drivers/Common/Common.h
  38  *  \brief Common library convenience headers, macros and functions.
  39  *
  40  *  Common utility headers containing macros, functions, enums and types which are common to all
  41  *  aspects of the library.
  42  *
  43  *  @{
  44  */
  45
  46 /** \defgroup Group_Debugging Debugging Macros
  47  *  \brief Convenience macros to aid in debugging applications.
  48  *
  49  *  Macros to aid debugging of a user application.
  50  */
  51
  52 /** \defgroup Group_GlobalInt Global Interrupt Macros
  53  *  \brief Convenience macros for the management of interrupts globally within the device.
  54  *
  55  *  Macros and functions to create and control global interrupts within the device.
  56  */
  57
  58 #ifndef __LUFA_COMMON_H__
  59 #define __LUFA_COMMON_H__
  60
  61         /* Macros: */
  62                 #define __INCLUDE_FROM_COMMON_H
  63
  64         /* Includes: */
  65                 #include <stdint.h>
  66                 #include <stdbool.h>
  67                 #include <string.h>
  68                 #include <stddef.h>
  69
  70                 #if defined(USE_LUFA_CONFIG_HEADER)
  71                         #include "LUFAConfig.h"
  72                 #endif
  73
  74                 #include "CompilerSpecific.h"
  75                 #include "Architectures.h"
  76                 #include "Attributes.h"
  77                 #include "BoardTypes.h"
  78
  79         /* Enable C linkage for C++ Compilers: */
  80                 #if defined(__cplusplus)
  81                         extern "C" {
  82                 #endif
  83
  84         /* Architecture specific utility includes: */
  85                 #if defined(__DOXYGEN__)
  86                         /** Type define for an unsigned integer the same width as the selected architecture's machine register.
  87                          *  This is distinct from the non-specific standard int data type, whose width is machine dependant but
  88                          *  which may not reflect the actual machine register width on some targets (e.g. AVR8).
  89                          */
  90                         typedef MACHINE_REG_t uint_reg_t;
  91                 #elif (ARCH == ARCH_AVR8)
  92                         #include <avr/io.h>
  93                         #include <avr/interrupt.h>
  94                         #include <avr/pgmspace.h>
  95                         #include <avr/eeprom.h>
  96                         #include <avr/boot.h>
  97                         #include <util/delay.h>
  98
  99                         typedef uint8_t uint_reg_t;
 100
 101                         #define ARCH_HAS_EEPROM_ADDRESS_SPACE
 102                         #define ARCH_HAS_FLASH_ADDRESS_SPACE
 103                         #define ARCH_HAS_MULTI_ADDRESS_SPACE
 104                         #define ARCH_LITTLE_ENDIAN
 105
 106                         #include "Endianness.h"
 107                 #elif (ARCH == ARCH_UC3)
 108                         #include <avr32/io.h>
 109
 110                         // === TODO: Find abstracted way to handle these ===
 111                         #define PROGMEM                  const
 112                         #define pgm_read_byte(x)         *x
 113                         #define memcmp_P(...)            memcmp(__VA_ARGS__)
 114                         #define memcpy_P(...)            memcpy(__VA_ARGS__)
 115                         // =================================================
 116
 117                         typedef uint32_t uint_reg_t;
 118
 119                         #define ARCH_BIG_ENDIAN
 120
 121                         #include "Endianness.h"
 122                 #else
 123                         #error Unknown device architecture specified.
 124                 #endif
 125
 126         /* Public Interface - May be used in end-application: */
 127                 /* Macros: */
 128                         /** Macro for encasing other multi-statement macros. This should be used along with an opening brace
 129                          *  before the start of any multi-statement macro, so that the macros contents as a whole are treated
 130                          *  as a discrete block and not as a list of separate statements which may cause problems when used as
 131                          *  a block (such as inline \c if statements).
 132                          */
 133                         #define MACROS                  do
 134
 135                         /** Macro for encasing other multi-statement macros. This should be used along with a preceding closing
 136                          *  brace at the end of any multi-statement macro, so that the macros contents as a whole are treated
 137                          *  as a discrete block and not as a list of separate statements which may cause problems when used as
 138                          *  a block (such as inline \c if statements).
 139                          */
 140                         #define MACROE                  while (0)
 141
 142                         /** Convenience macro to determine the larger of two values.
 143                          *
 144                          *  \note This macro should only be used with operands that do not have side effects from being evaluated
 145                          *        multiple times.
 146                          *
 147                          *  \param[in] x  First value to compare
 148                          *  \param[in] y  First value to compare
 149                          *
 150                          *  \return The larger of the two input parameters
 151                          */
 152                         #if !defined(MAX) || defined(__DOXYGEN__)
 153                                 #define MAX(x, y)               ((x > y) ? x : y)
 154                         #endif
 155
 156                         /** Convenience macro to determine the smaller of two values.
 157                          *
 158                          *  \note This macro should only be used with operands that do not have side effects from being evaluated
 159                          *        multiple times.
 160                          *
 161                          *  \param[in] x  First value to compare
 162                          *  \param[in] y  First value to compare
 163                          *
 164                          *  \return The smaller of the two input parameters
 165                          */
 166                         #if !defined(MIN) || defined(__DOXYGEN__)
 167                                 #define MIN(x, y)               ((x < y) ? x : y)
 168                         #endif
 169
 170                         #if (ARCH == ARCH_AVR8) || defined(__DOXYGEN__)
 171                                 /** Defines a volatile \c NOP statement which cannot be optimized out by the compiler, and thus can always
 172                                  *  be set as a breakpoint in the resulting code. Useful for debugging purposes, where the optimizer
 173                                  *  removes/reorders code to the point where break points cannot reliably be set.
 174                                  *
 175                                  *  \note This macro is not available for all architectures.
 176                                  *
 177                                  *  \ingroup Group_Debugging
 178                                  */
 179                                 #define JTAG_DEBUG_POINT()      __asm__ __volatile__ ("NOP" ::)
 180
 181                                 /** Defines an explicit JTAG break point in the resulting binary via the assembly \c BREAK statement. When
 182                                  *  a JTAG is used, this causes the program execution to halt when reached until manually resumed.
 183                                  *
 184                                  *  \note This macro is not available for all architectures.
 185                                  *
 186                                  *  \ingroup Group_Debugging
 187                                  */
 188                                 #define JTAG_DEBUG_BREAK()      __asm__ __volatile__ ("BREAK" ::)
 189
 190                                 /** Macro for testing condition "x" and breaking via \ref JTAG_DEBUG_BREAK() if the condition is false.
 191                                  *
 192                                  *  \note This macro is not available for all architectures.
 193                                  *
 194                                  *  \param[in] Condition  Condition that will be evaluated.
 195                                  *
 196                                  *  \ingroup Group_Debugging
 197                                 */
 198                                 #define JTAG_DEBUG_ASSERT(Condition)    MACROS{ if (!(Condition)) { JTAG_DEBUG_BREAK(); } }MACROE
 199
 200                                 /** Macro for testing condition "x" and writing debug data to the stdout stream if \c false. The stdout stream
 201                                  *  must be pre-initialized before this macro is run and linked to an output device, such as the microcontroller's
 202                                  *  USART peripheral.
 203                                  *
 204                                  *  The output takes the form "{FILENAME}: Function {FUNCTION NAME}, Line {LINE NUMBER}: Assertion {Condition} failed."
 205                                  *
 206                                  *  \note This macro is not available for all architectures.
 207                                  *
 208                                  *  \param[in] Condition  Condition that will be evaluated,
 209                                  *
 210                                  *  \ingroup Group_Debugging
 211                                  */
 212                                 #define STDOUT_ASSERT(Condition)        MACROS{ if (!(x)) { printf_P(PSTR("%s: Function \"%s\", Line %d: "   \
 213                                                                                 "Assertion \"%s\" failed.\r\n"),     \
 214                                                                                 __FILE__, __func__, __LINE__, #Condition); } }MACROE
 215
 216                                 #if !defined(pgm_read_ptr) || defined(__DOXYGEN__)
 217                                         /** Reads a pointer out of PROGMEM space on the AVR8 architecture. This is currently a wrapper for the
 218                                          *  avr-libc \c pgm_read_ptr() macro with a \c void* cast, so that its value can be assigned directly
 219                                          *  to a pointer variable or used in pointer arithmetic without further casting in C. In a future
 220                                          *  avr-libc distribution this will be part of the standard API and will be implemented in a more formal
 221                                          *  manner.
 222                                          *
 223                                          *  \note This macro is not available for all architectures.
 224                                          *
 225                                          *  \param[in] Address  Address of the pointer to read.
 226                                          *
 227                                          *  \return Pointer retrieved from PROGMEM space.
 228                                          */
 229                                         #define pgm_read_ptr(Address)        (void*)pgm_read_word(Address)
 230                                 #endif
 231                         #endif
 232
 233                         #if !defined(ISR) || defined(__DOXYGEN__)
 234                                 /** Macro for the definition of interrupt service routines, so that the compiler can insert the required
 235                                  *  prologue and epilogue code to properly manage the interrupt routine without affecting the main thread's
 236                                  *  state with unintentional side-effects.
 237                                  *
 238                                  *  Interrupt handlers written using this macro may still need to be registered with the microcontroller's
 239                                  *  Interrupt Controller (if present) before they will properly handle incoming interrupt events.
 240                                  *
 241                                  *  \note This macro is only supplied on some architectures, where the standard library does not include a valid
 242                                  *        definition. If an existing definition exists, the alternative definition here will be ignored.
 243                                  *
 244                                  *  \ingroup Group_GlobalInt
 245                                  *
 246                                  *  \param Name  Unique name of the interrupt service routine.
 247                                  */
 248                                 #define ISR(Name, ...)                  void Name (void) __attribute__((__interrupt__)) __VA_ARGS__; void Name (void)
 249                         #endif
 250
 251                 /* Inline Functions: */
 252                         /** Function to reverse the individual bits in a byte - i.e. bit 7 is moved to bit 0, bit 6 to bit 1,
 253                          *  etc.
 254                          *
 255                          *  \param[in] Byte  Byte of data whose bits are to be reversed.
 256                          */
 257                         static inline uint8_t BitReverse(uint8_t Byte) ATTR_WARN_UNUSED_RESULT ATTR_CONST;
 258                         static inline uint8_t BitReverse(uint8_t Byte)
 259                         {
 260                                 Byte = (((Byte & 0xF0) >> 4) | ((Byte & 0x0F) << 4));
 261                                 Byte = (((Byte & 0xCC) >> 2) | ((Byte & 0x33) << 2));
 262                                 Byte = (((Byte & 0xAA) >> 1) | ((Byte & 0x55) << 1));
 263
 264                                 return Byte;
 265                         }
 266
 267                         /** Function to perform a blocking delay for a specified number of milliseconds. The actual delay will be
 268                          *  at a minimum the specified number of milliseconds, however due to loop overhead and internal calculations
 269                          *  may be slightly higher.
 270                          *
 271                          *  \param[in] Milliseconds  Number of milliseconds to delay
 272                          */
 273                         static inline void Delay_MS(uint8_t Milliseconds) ATTR_ALWAYS_INLINE;
 274                         static inline void Delay_MS(uint8_t Milliseconds)
 275                         {
 276                                 #if (ARCH == ARCH_AVR8)
 277                                 if (GCC_IS_COMPILE_CONST(Milliseconds))
 278                                 {
 279                                         _delay_ms(Milliseconds);
 280                                 }
 281                                 else
 282                                 {
 283                                         while (Milliseconds--)
 284                                           _delay_ms(1);
 285                                 }
 286                                 #elif (ARCH == ARCH_UC3)
 287                                 while (Milliseconds--)
 288                                 {
 289                                         __builtin_mtsr(AVR32_COUNT, 0);
 290                                         while (__builtin_mfsr(AVR32_COUNT) < (F_CPU / 1000));
 291                                 }
 292                                 #endif
 293                         }
 294
 295                         /** Retrieves a mask which contains the current state of the global interrupts for the device. This
 296                          *  value can be stored before altering the global interrupt enable state, before restoring the
 297                          *  flag(s) back to their previous values after a critical section using \ref SetGlobalInterruptMask().
 298                          *
 299                          *  \ingroup Group_GlobalInt
 300                          *
 301                          *  \return  Mask containing the current Global Interrupt Enable Mask bit(s).
 302                          */
 303                         static inline uint_reg_t GetGlobalInterruptMask(void) ATTR_ALWAYS_INLINE ATTR_WARN_UNUSED_RESULT;
 304                         static inline uint_reg_t GetGlobalInterruptMask(void)
 305                         {
 306                                 GCC_MEMORY_BARRIER();
 307
 308                                 #if (ARCH == ARCH_AVR8)
 309                                 return SREG;
 310                                 #elif (ARCH == ARCH_UC3)
 311                                 return __builtin_mfsr(AVR32_SR);
 312                                 #endif
 313
 314                                 GCC_MEMORY_BARRIER();
 315                         }
 316
 317                         /** Sets the global interrupt enable state of the microcontroller to the mask passed into the function.
 318                          *  This can be combined with \ref GetGlobalInterruptMask() to save and restore the Global Interrupt Enable
 319                          *  Mask bit(s) of the device after a critical section has completed.
 320                          *
 321                          *  \ingroup Group_GlobalInt
 322                          *
 323                          *  \param[in] GlobalIntState  Global Interrupt Enable Mask value to use
 324                          */
 325                         static inline void SetGlobalInterruptMask(const uint_reg_t GlobalIntState) ATTR_ALWAYS_INLINE;
 326                         static inline void SetGlobalInterruptMask(const uint_reg_t GlobalIntState)
 327                         {
 328                                 GCC_MEMORY_BARRIER();
 329
 330                                 #if (ARCH == ARCH_AVR8)
 331                                 SREG = GlobalIntState;
 332                                 #elif (ARCH == ARCH_UC3)
 333                                 if (GlobalIntState & AVR32_SR_GM)
 334                                   __builtin_ssrf(AVR32_SR_GM_OFFSET);
 335                                 else
 336                                   __builtin_csrf(AVR32_SR_GM_OFFSET);
 337                                 #endif
 338
 339                                 GCC_MEMORY_BARRIER();
 340                         }
 341
 342                         /** Enables global interrupt handling for the device, allowing interrupts to be handled.
 343                          *
 344                          *  \ingroup Group_GlobalInt
 345                          */
 346                         static inline void GlobalInterruptEnable(void) ATTR_ALWAYS_INLINE;
 347                         static inline void GlobalInterruptEnable(void)
 348                         {
 349                                 GCC_MEMORY_BARRIER();
 350
 351                                 #if (ARCH == ARCH_AVR8)
 352                                 sei();
 353                                 #elif (ARCH == ARCH_UC3)
 354                                 __builtin_csrf(AVR32_SR_GM_OFFSET);
 355                                 #endif
 356
 357                                 GCC_MEMORY_BARRIER();
 358                         }
 359
 360                         /** Disabled global interrupt handling for the device, preventing interrupts from being handled.
 361                          *
 362                          *  \ingroup Group_GlobalInt
 363                          */
 364                         static inline void GlobalInterruptDisable(void) ATTR_ALWAYS_INLINE;
 365                         static inline void GlobalInterruptDisable(void)
 366                         {
 367                                 GCC_MEMORY_BARRIER();
 368
 369                                 #if (ARCH == ARCH_AVR8)
 370                                 cli();
 371                                 #elif (ARCH == ARCH_UC3)
 372                                 __builtin_ssrf(AVR32_SR_GM_OFFSET);
 373                                 #endif
 374
 375                                 GCC_MEMORY_BARRIER();
 376                         }
 377
 378         /* Disable C linkage for C++ Compilers: */
 379                 #if defined(__cplusplus)
 380                         }
 381                 #endif
 382
 383 #endif
 384
 385 /** @} */
 386