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_GlobalInt Global Interrupt Macros
  47  *  \brief Convenience macros for the management of interrupts globally within the device.
  48  *
  49  *  Macros and functions to create and control global interrupts within the device.
  50  */
  51
  52 #ifndef __LUFA_COMMON_H__
  53 #define __LUFA_COMMON_H__
  54
  55         /* Macros: */
  56                 #define __INCLUDE_FROM_COMMON_H
  57
  58         /* Includes: */
  59                 #include <stdint.h>
  60                 #include <stdbool.h>
  61                 #include <string.h>
  62                 #include <stddef.h>
  63
  64                 #if defined(USE_LUFA_CONFIG_HEADER)
  65                         #include "LUFAConfig.h"
  66                 #endif
  67
  68                 #include "ArchitectureSpecific.h"
  69                 #include "CompilerSpecific.h"
  70                 #include "Architectures.h"
  71                 #include "Attributes.h"
  72                 #include "BoardTypes.h"
  73
  74         /* Enable C linkage for C++ Compilers: */
  75                 #if defined(__cplusplus)
  76                         extern "C" {
  77                 #endif
  78
  79         /* Architecture specific utility includes: */
  80                 #if defined(__DOXYGEN__)
  81                         /** Type define for an unsigned integer the same width as the selected architecture's machine register.
  82                          *  This is distinct from the non-specific standard int data type, whose width is machine dependant but
  83                          *  which may not reflect the actual machine register width on some targets (e.g. AVR8).
  84                          */
  85                         typedef MACHINE_REG_t uint_reg_t;
  86                 #elif (ARCH == ARCH_AVR8)
  87                         #include <avr/io.h>
  88                         #include <avr/interrupt.h>
  89                         #include <avr/pgmspace.h>
  90                         #include <avr/eeprom.h>
  91                         #include <avr/boot.h>
  92                         #include <util/delay.h>
  93
  94                         typedef uint8_t uint_reg_t;
  95
  96                         #define ARCH_HAS_EEPROM_ADDRESS_SPACE
  97                         #define ARCH_HAS_FLASH_ADDRESS_SPACE
  98                         #define ARCH_HAS_MULTI_ADDRESS_SPACE
  99                         #define ARCH_LITTLE_ENDIAN
 100
 101                         #include "Endianness.h"
 102                 #elif (ARCH == ARCH_UC3)
 103                         #include <avr32/io.h>
 104
 105                         // === TODO: Find abstracted way to handle these ===
 106                         #define PROGMEM                  const
 107                         #define pgm_read_byte(x)         *x
 108                         #define memcmp_P(...)            memcmp(__VA_ARGS__)
 109                         #define memcpy_P(...)            memcpy(__VA_ARGS__)
 110                         // =================================================
 111
 112                         typedef uint32_t uint_reg_t;
 113
 114                         #define ARCH_BIG_ENDIAN
 115
 116                         #include "Endianness.h"
 117                 #elif (ARCH == ARCH_XMEGA)
 118                         #include <avr/io.h>
 119                         #include <avr/interrupt.h>
 120                         #include <avr/pgmspace.h>
 121                         #include <avr/eeprom.h>
 122                         #include <util/delay.h>
 123
 124                         typedef uint8_t uint_reg_t;
 125
 126                         #define ARCH_HAS_EEPROM_ADDRESS_SPACE
 127                         #define ARCH_HAS_FLASH_ADDRESS_SPACE
 128                         #define ARCH_HAS_MULTI_ADDRESS_SPACE
 129                         #define ARCH_LITTLE_ENDIAN
 130
 131                         #include "Endianness.h"
 132                 #else
 133                         #error Unknown device architecture specified.
 134                 #endif
 135
 136         /* Public Interface - May be used in end-application: */
 137                 /* Macros: */
 138                         /** Macro for encasing other multi-statement macros. This should be used along with an opening brace
 139                          *  before the start of any multi-statement macro, so that the macros contents as a whole are treated
 140                          *  as a discrete block and not as a list of separate statements which may cause problems when used as
 141                          *  a block (such as inline \c if statements).
 142                          */
 143                         #define MACROS                  do
 144
 145                         /** Macro for encasing other multi-statement macros. This should be used along with a preceding closing
 146                          *  brace at the end of any multi-statement macro, so that the macros contents as a whole are treated
 147                          *  as a discrete block and not as a list of separate statements which may cause problems when used as
 148                          *  a block (such as inline \c if statements).
 149                          */
 150                         #define MACROE                  while (0)
 151
 152                         /** Convenience macro to determine the larger of two values.
 153                          *
 154                          *  \note This macro should only be used with operands that do not have side effects from being evaluated
 155                          *        multiple times.
 156                          *
 157                          *  \param[in] x  First value to compare
 158                          *  \param[in] y  First value to compare
 159                          *
 160                          *  \return The larger of the two input parameters
 161                          */
 162                         #if !defined(MAX) || defined(__DOXYGEN__)
 163                                 #define MAX(x, y)               (((x) > (y)) ? (x) : (y))
 164                         #endif
 165
 166                         /** Convenience macro to determine the smaller of two values.
 167                          *
 168                          *  \note This macro should only be used with operands that do not have side effects from being evaluated
 169                          *        multiple times.
 170                          *
 171                          *  \param[in] x  First value to compare
 172                          *  \param[in] y  First value to compare
 173                          *
 174                          *  \return The smaller of the two input parameters
 175                          */
 176                         #if !defined(MIN) || defined(__DOXYGEN__)
 177                                 #define MIN(x, y)               (((x) < (y)) ? (x) : (y))
 178                         #endif
 179
 180                         #if !defined(STRINGIFY) || defined(__DOXYGEN__)
 181                                 /** Converts the given input into a string, via the C Preprocessor. This macro puts literal quotation
 182                                  *  marks around the input, converting the source into a string literal.
 183                                  *
 184                                  *  \param[in] x  Input to convert into a string literal.
 185                                  *
 186                                  *  \return String version of the input.
 187                                  */
 188                                 #define STRINGIFY(x)            #x
 189
 190                                 /** Converts the given input into a string after macro expansion, via the C Preprocessor. This macro puts
 191                                  *  literal quotation marks around the expanded input, converting the source into a string literal.
 192                                  *
 193                                  *  \param[in] x  Input to expand and convert into a string literal.
 194                                  *
 195                                  *  \return String version of the expanded input.
 196                                  */
 197                                 #define STRINGIFY_EXPANDED(x)   STRINGIFY(x)
 198                         #endif
 199
 200                         #if !defined(ISR) || defined(__DOXYGEN__)
 201                                 /** Macro for the definition of interrupt service routines, so that the compiler can insert the required
 202                                  *  prologue and epilogue code to properly manage the interrupt routine without affecting the main thread's
 203                                  *  state with unintentional side-effects.
 204                                  *
 205                                  *  Interrupt handlers written using this macro may still need to be registered with the microcontroller's
 206                                  *  Interrupt Controller (if present) before they will properly handle incoming interrupt events.
 207                                  *
 208                                  *  \note This macro is only supplied on some architectures, where the standard library does not include a valid
 209                                  *        definition. If an existing definition exists, the alternative definition here will be ignored.
 210                                  *
 211                                  *  \ingroup Group_GlobalInt
 212                                  *
 213                                  *  \param Name  Unique name of the interrupt service routine.
 214                                  */
 215                                 #define ISR(Name, ...)                  void Name (void) __attribute__((__interrupt__)) __VA_ARGS__; void Name (void)
 216                         #endif
 217
 218                 /* Inline Functions: */
 219                         /** Function to reverse the individual bits in a byte - i.e. bit 7 is moved to bit 0, bit 6 to bit 1,
 220                          *  etc.
 221                          *
 222                          *  \param[in] Byte  Byte of data whose bits are to be reversed.
 223                          */
 224                         static inline uint8_t BitReverse(uint8_t Byte) ATTR_WARN_UNUSED_RESULT ATTR_CONST;
 225                         static inline uint8_t BitReverse(uint8_t Byte)
 226                         {
 227                                 Byte = (((Byte & 0xF0) >> 4) | ((Byte & 0x0F) << 4));
 228                                 Byte = (((Byte & 0xCC) >> 2) | ((Byte & 0x33) << 2));
 229                                 Byte = (((Byte & 0xAA) >> 1) | ((Byte & 0x55) << 1));
 230
 231                                 return Byte;
 232                         }
 233
 234                         /** Function to perform a blocking delay for a specified number of milliseconds. The actual delay will be
 235                          *  at a minimum the specified number of milliseconds, however due to loop overhead and internal calculations
 236                          *  may be slightly higher.
 237                          *
 238                          *  \param[in] Milliseconds  Number of milliseconds to delay
 239                          */
 240                         static inline void Delay_MS(uint16_t Milliseconds) ATTR_ALWAYS_INLINE;
 241                         static inline void Delay_MS(uint16_t Milliseconds)
 242                         {
 243                                 #if (ARCH == ARCH_AVR8)
 244                                 if (GCC_IS_COMPILE_CONST(Milliseconds))
 245                                 {
 246                                         _delay_ms(Milliseconds);
 247                                 }
 248                                 else
 249                                 {
 250                                         while (Milliseconds--)
 251                                           _delay_ms(1);
 252                                 }
 253                                 #elif (ARCH == ARCH_UC3)
 254                                 while (Milliseconds--)
 255                                 {
 256                                         __builtin_mtsr(AVR32_COUNT, 0);
 257                                         while (__builtin_mfsr(AVR32_COUNT) < (F_CPU / 1000));
 258                                 }
 259                                 #elif (ARCH == ARCH_XMEGA)
 260                                 if (GCC_IS_COMPILE_CONST(Milliseconds))
 261                                 {
 262                                         _delay_ms(Milliseconds);
 263                                 }
 264                                 else
 265                                 {
 266                                         while (Milliseconds--)
 267                                           _delay_ms(1);
 268                                 }
 269                                 #endif
 270                         }
 271
 272                         /** Retrieves a mask which contains the current state of the global interrupts for the device. This
 273                          *  value can be stored before altering the global interrupt enable state, before restoring the
 274                          *  flag(s) back to their previous values after a critical section using \ref SetGlobalInterruptMask().
 275                          *
 276                          *  \ingroup Group_GlobalInt
 277                          *
 278                          *  \return  Mask containing the current Global Interrupt Enable Mask bit(s).
 279                          */
 280                         static inline uint_reg_t GetGlobalInterruptMask(void) ATTR_ALWAYS_INLINE ATTR_WARN_UNUSED_RESULT;
 281                         static inline uint_reg_t GetGlobalInterruptMask(void)
 282                         {
 283                                 GCC_MEMORY_BARRIER();
 284
 285                                 #if (ARCH == ARCH_AVR8)
 286                                 return SREG;
 287                                 #elif (ARCH == ARCH_UC3)
 288                                 return __builtin_mfsr(AVR32_SR);
 289                                 #elif (ARCH == ARCH_XMEGA)
 290                                 return SREG;
 291                                 #endif
 292
 293                                 GCC_MEMORY_BARRIER();
 294                         }
 295
 296                         /** Sets the global interrupt enable state of the microcontroller to the mask passed into the function.
 297                          *  This can be combined with \ref GetGlobalInterruptMask() to save and restore the Global Interrupt Enable
 298                          *  Mask bit(s) of the device after a critical section has completed.
 299                          *
 300                          *  \ingroup Group_GlobalInt
 301                          *
 302                          *  \param[in] GlobalIntState  Global Interrupt Enable Mask value to use
 303                          */
 304                         static inline void SetGlobalInterruptMask(const uint_reg_t GlobalIntState) ATTR_ALWAYS_INLINE;
 305                         static inline void SetGlobalInterruptMask(const uint_reg_t GlobalIntState)
 306                         {
 307                                 GCC_MEMORY_BARRIER();
 308
 309                                 #if (ARCH == ARCH_AVR8)
 310                                 SREG = GlobalIntState;
 311                                 #elif (ARCH == ARCH_UC3)
 312                                 if (GlobalIntState & AVR32_SR_GM)
 313                                   __builtin_ssrf(AVR32_SR_GM_OFFSET);
 314                                 else
 315                                   __builtin_csrf(AVR32_SR_GM_OFFSET);
 316                                 #elif (ARCH == ARCH_XMEGA)
 317                                 SREG = GlobalIntState;
 318                                 #endif
 319
 320                                 GCC_MEMORY_BARRIER();
 321                         }
 322
 323                         /** Enables global interrupt handling for the device, allowing interrupts to be handled.
 324                          *
 325                          *  \ingroup Group_GlobalInt
 326                          */
 327                         static inline void GlobalInterruptEnable(void) ATTR_ALWAYS_INLINE;
 328                         static inline void GlobalInterruptEnable(void)
 329                         {
 330                                 GCC_MEMORY_BARRIER();
 331
 332                                 #if (ARCH == ARCH_AVR8)
 333                                 sei();
 334                                 #elif (ARCH == ARCH_UC3)
 335                                 __builtin_csrf(AVR32_SR_GM_OFFSET);
 336                                 #elif (ARCH == ARCH_XMEGA)
 337                                 sei();
 338                                 #endif
 339
 340                                 GCC_MEMORY_BARRIER();
 341                         }
 342
 343                         /** Disabled global interrupt handling for the device, preventing interrupts from being handled.
 344                          *
 345                          *  \ingroup Group_GlobalInt
 346                          */
 347                         static inline void GlobalInterruptDisable(void) ATTR_ALWAYS_INLINE;
 348                         static inline void GlobalInterruptDisable(void)
 349                         {
 350                                 GCC_MEMORY_BARRIER();
 351
 352                                 #if (ARCH == ARCH_AVR8)
 353                                 cli();
 354                                 #elif (ARCH == ARCH_UC3)
 355                                 __builtin_ssrf(AVR32_SR_GM_OFFSET);
 356                                 #elif (ARCH == ARCH_XMEGA)
 357                                 cli();
 358                                 #endif
 359
 360                                 GCC_MEMORY_BARRIER();
 361                         }
 362
 363         /* Disable C linkage for C++ Compilers: */
 364                 #if defined(__cplusplus)
 365                         }
 366                 #endif
 367
 368 #endif
 369
 370 /** @} */
 371