1 | /** |
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2 | * @file rtems/score/cpu.h |
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3 | */ |
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4 | |
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5 | /* |
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6 | * This include file contains information pertaining to the AVR |
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7 | * processor. |
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8 | * |
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9 | * COPYRIGHT (c) 1989-2006. |
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10 | * On-Line Applications Research Corporation (OAR). |
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11 | * |
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12 | * The license and distribution terms for this file may be |
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13 | * found in the file LICENSE in this distribution or at |
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14 | * http://www.rtems.com/license/LICENSE. |
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15 | */ |
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16 | |
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17 | #ifndef _RTEMS_SCORE_CPU_H |
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18 | #define _RTEMS_SCORE_CPU_H |
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19 | |
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20 | #ifdef __cplusplus |
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21 | extern "C" { |
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22 | #endif |
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23 | |
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24 | #include <rtems/score/types.h> |
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25 | #include <rtems/score/avr.h> |
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26 | #include <avr/common.h> |
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27 | |
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28 | /* conditional compilation parameters */ |
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29 | |
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30 | #ifndef RTEMS_USE_16_BIT_OBJECT |
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31 | #define RTEMS_USE_16_BIT_OBJECT |
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32 | #endif |
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33 | |
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34 | /* |
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35 | * Should the calls to _Thread_Enable_dispatch be inlined? |
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36 | * |
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37 | * If TRUE, then they are inlined. |
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38 | * If FALSE, then a subroutine call is made. |
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39 | * |
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40 | * Basically this is an example of the classic trade-off of size |
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41 | * versus speed. Inlining the call (TRUE) typically increases the |
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42 | * size of RTEMS while speeding up the enabling of dispatching. |
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43 | * [NOTE: In general, the _Thread_Dispatch_disable_level will |
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44 | * only be 0 or 1 unless you are in an interrupt handler and that |
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45 | * interrupt handler invokes the executive.] When not inlined |
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46 | * something calls _Thread_Enable_dispatch which in turns calls |
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47 | * _Thread_Dispatch. If the enable dispatch is inlined, then |
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48 | * one subroutine call is avoided entirely.] |
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49 | * |
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50 | * AVR Specific Information: |
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51 | * |
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52 | * XXX document implementation including references if appropriate |
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53 | */ |
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54 | |
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55 | #define CPU_INLINE_ENABLE_DISPATCH FALSE |
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56 | |
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57 | /* |
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58 | * Should the body of the search loops in _Thread_queue_Enqueue_priority |
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59 | * be unrolled one time? In unrolled each iteration of the loop examines |
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60 | * two "nodes" on the chain being searched. Otherwise, only one node |
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61 | * is examined per iteration. |
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62 | * |
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63 | * If TRUE, then the loops are unrolled. |
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64 | * If FALSE, then the loops are not unrolled. |
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65 | * |
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66 | * The primary factor in making this decision is the cost of disabling |
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67 | * and enabling interrupts (_ISR_Flash) versus the cost of rest of the |
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68 | * body of the loop. On some CPUs, the flash is more expensive than |
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69 | * one iteration of the loop body. In this case, it might be desirable |
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70 | * to unroll the loop. It is important to note that on some CPUs, this |
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71 | * code is the longest interrupt disable period in RTEMS. So it is |
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72 | * necessary to strike a balance when setting this parameter. |
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73 | * |
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74 | * AVR Specific Information: |
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75 | * |
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76 | * XXX document implementation including references if appropriate |
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77 | */ |
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78 | |
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79 | #define CPU_UNROLL_ENQUEUE_PRIORITY FALSE |
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80 | |
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81 | /* |
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82 | * Does RTEMS manage a dedicated interrupt stack in software? |
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83 | * |
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84 | * If TRUE, then a stack is allocated in _ISR_Handler_initialization. |
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85 | * If FALSE, nothing is done. |
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86 | * |
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87 | * If the CPU supports a dedicated interrupt stack in hardware, |
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88 | * then it is generally the responsibility of the BSP to allocate it |
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89 | * and set it up. |
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90 | * |
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91 | * If the CPU does not support a dedicated interrupt stack, then |
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92 | * the porter has two options: (1) execute interrupts on the |
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93 | * stack of the interrupted task, and (2) have RTEMS manage a dedicated |
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94 | * interrupt stack. |
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95 | * |
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96 | * If this is TRUE, CPU_ALLOCATE_INTERRUPT_STACK should also be TRUE. |
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97 | * |
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98 | * Only one of CPU_HAS_SOFTWARE_INTERRUPT_STACK and |
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99 | * CPU_HAS_HARDWARE_INTERRUPT_STACK should be set to TRUE. It is |
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100 | * possible that both are FALSE for a particular CPU. Although it |
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101 | * is unclear what that would imply about the interrupt processing |
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102 | * procedure on that CPU. |
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103 | * |
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104 | * AVR Specific Information: |
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105 | * |
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106 | * XXX document implementation including references if appropriate |
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107 | */ |
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108 | |
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109 | #define CPU_HAS_SOFTWARE_INTERRUPT_STACK FALSE |
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110 | |
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111 | /* |
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112 | * Does this CPU have hardware support for a dedicated interrupt stack? |
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113 | * |
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114 | * If TRUE, then it must be installed during initialization. |
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115 | * If FALSE, then no installation is performed. |
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116 | * |
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117 | * If this is TRUE, CPU_ALLOCATE_INTERRUPT_STACK should also be TRUE. |
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118 | * |
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119 | * Only one of CPU_HAS_SOFTWARE_INTERRUPT_STACK and |
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120 | * CPU_HAS_HARDWARE_INTERRUPT_STACK should be set to TRUE. It is |
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121 | * possible that both are FALSE for a particular CPU. Although it |
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122 | * is unclear what that would imply about the interrupt processing |
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123 | * procedure on that CPU. |
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124 | * |
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125 | * AVR Specific Information: |
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126 | * |
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127 | * XXX document implementation including references if appropriate |
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128 | */ |
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129 | |
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130 | #define CPU_HAS_HARDWARE_INTERRUPT_STACK TRUE |
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131 | |
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132 | /* |
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133 | * Does RTEMS allocate a dedicated interrupt stack in the Interrupt Manager? |
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134 | * |
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135 | * If TRUE, then the memory is allocated during initialization. |
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136 | * If FALSE, then the memory is allocated during initialization. |
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137 | * |
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138 | * This should be TRUE is CPU_HAS_SOFTWARE_INTERRUPT_STACK is TRUE. |
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139 | * |
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140 | * AVR Specific Information: |
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141 | * |
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142 | * XXX document implementation including references if appropriate |
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143 | */ |
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144 | |
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145 | #define CPU_ALLOCATE_INTERRUPT_STACK TRUE |
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146 | |
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147 | /* |
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148 | * Does the RTEMS invoke the user's ISR with the vector number and |
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149 | * a pointer to the saved interrupt frame (1) or just the vector |
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150 | * number (0)? |
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151 | * |
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152 | * AVR Specific Information: |
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153 | * |
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154 | * XXX document implementation including references if appropriate |
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155 | */ |
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156 | |
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157 | #define CPU_ISR_PASSES_FRAME_POINTER 0 |
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158 | |
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159 | /* |
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160 | * Does the CPU follow the simple vectored interrupt model? |
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161 | * |
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162 | * If TRUE, then RTEMS allocates the vector table it internally manages. |
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163 | * If FALSE, then the BSP is assumed to allocate and manage the vector |
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164 | * table |
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165 | * |
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166 | * AVR Specific Information: |
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167 | * |
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168 | * XXX document implementation including references if appropriate |
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169 | */ |
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170 | #define CPU_SIMPLE_VECTORED_INTERRUPTS TRUE |
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171 | |
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172 | /* |
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173 | * Does the CPU have hardware floating point? |
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174 | * |
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175 | * If TRUE, then the RTEMS_FLOATING_POINT task attribute is supported. |
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176 | * If FALSE, then the RTEMS_FLOATING_POINT task attribute is ignored. |
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177 | * |
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178 | * If there is a FP coprocessor such as the i387 or mc68881, then |
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179 | * the answer is TRUE. |
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180 | * |
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181 | * The macro name "AVR_HAS_FPU" should be made CPU specific. |
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182 | * It indicates whether or not this CPU model has FP support. For |
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183 | * example, it would be possible to have an i386_nofp CPU model |
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184 | * which set this to false to indicate that you have an i386 without |
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185 | * an i387 and wish to leave floating point support out of RTEMS. |
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186 | * |
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187 | * The CPU_SOFTWARE_FP is used to indicate whether or not there |
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188 | * is software implemented floating point that must be context |
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189 | * switched. The determination of whether or not this applies |
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190 | * is very tool specific and the state saved/restored is also |
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191 | * compiler specific. |
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192 | * |
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193 | * AVR Specific Information: |
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194 | * |
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195 | * XXX document implementation including references if appropriate |
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196 | */ |
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197 | |
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198 | #if ( AVR_HAS_FPU == 1 ) |
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199 | #define CPU_HARDWARE_FP TRUE |
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200 | #else |
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201 | #define CPU_HARDWARE_FP FALSE |
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202 | #endif |
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203 | #define CPU_SOFTWARE_FP FALSE |
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204 | |
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205 | /* |
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206 | * Are all tasks RTEMS_FLOATING_POINT tasks implicitly? |
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207 | * |
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208 | * If TRUE, then the RTEMS_FLOATING_POINT task attribute is assumed. |
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209 | * If FALSE, then the RTEMS_FLOATING_POINT task attribute is followed. |
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210 | * |
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211 | * So far, the only CPUs in which this option has been used are the |
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212 | * HP PA-RISC and PowerPC. On the PA-RISC, The HP C compiler and |
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213 | * gcc both implicitly used the floating point registers to perform |
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214 | * integer multiplies. Similarly, the PowerPC port of gcc has been |
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215 | * seen to allocate floating point local variables and touch the FPU |
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216 | * even when the flow through a subroutine (like vfprintf()) might |
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217 | * not use floating point formats. |
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218 | * |
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219 | * If a function which you would not think utilize the FP unit DOES, |
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220 | * then one can not easily predict which tasks will use the FP hardware. |
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221 | * In this case, this option should be TRUE. |
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222 | * |
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223 | * If CPU_HARDWARE_FP is FALSE, then this should be FALSE as well. |
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224 | * |
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225 | * AVR Specific Information: |
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226 | * |
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227 | * XXX document implementation including references if appropriate |
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228 | */ |
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229 | |
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230 | #define CPU_ALL_TASKS_ARE_FP TRUE |
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231 | |
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232 | /* |
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233 | * Should the IDLE task have a floating point context? |
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234 | * |
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235 | * If TRUE, then the IDLE task is created as a RTEMS_FLOATING_POINT task |
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236 | * and it has a floating point context which is switched in and out. |
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237 | * If FALSE, then the IDLE task does not have a floating point context. |
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238 | * |
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239 | * Setting this to TRUE negatively impacts the time required to preempt |
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240 | * the IDLE task from an interrupt because the floating point context |
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241 | * must be saved as part of the preemption. |
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242 | * |
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243 | * AVR Specific Information: |
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244 | * |
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245 | * XXX document implementation including references if appropriate |
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246 | */ |
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247 | |
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248 | #define CPU_IDLE_TASK_IS_FP FALSE |
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249 | |
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250 | /* |
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251 | * Should the saving of the floating point registers be deferred |
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252 | * until a context switch is made to another different floating point |
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253 | * task? |
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254 | * |
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255 | * If TRUE, then the floating point context will not be stored until |
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256 | * necessary. It will remain in the floating point registers and not |
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257 | * disturned until another floating point task is switched to. |
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258 | * |
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259 | * If FALSE, then the floating point context is saved when a floating |
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260 | * point task is switched out and restored when the next floating point |
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261 | * task is restored. The state of the floating point registers between |
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262 | * those two operations is not specified. |
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263 | * |
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264 | * If the floating point context does NOT have to be saved as part of |
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265 | * interrupt dispatching, then it should be safe to set this to TRUE. |
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266 | * |
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267 | * Setting this flag to TRUE results in using a different algorithm |
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268 | * for deciding when to save and restore the floating point context. |
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269 | * The deferred FP switch algorithm minimizes the number of times |
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270 | * the FP context is saved and restored. The FP context is not saved |
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271 | * until a context switch is made to another, different FP task. |
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272 | * Thus in a system with only one FP task, the FP context will never |
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273 | * be saved or restored. |
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274 | * |
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275 | * AVR Specific Information: |
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276 | * |
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277 | * XXX document implementation including references if appropriate |
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278 | */ |
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279 | |
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280 | #define CPU_USE_DEFERRED_FP_SWITCH TRUE |
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281 | |
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282 | /* |
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283 | * Does this port provide a CPU dependent IDLE task implementation? |
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284 | * |
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285 | * If TRUE, then the routine _CPU_Thread_Idle_body |
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286 | * must be provided and is the default IDLE thread body instead of |
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287 | * _CPU_Thread_Idle_body. |
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288 | * |
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289 | * If FALSE, then use the generic IDLE thread body if the BSP does |
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290 | * not provide one. |
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291 | * |
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292 | * This is intended to allow for supporting processors which have |
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293 | * a low power or idle mode. When the IDLE thread is executed, then |
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294 | * the CPU can be powered down. |
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295 | * |
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296 | * The order of precedence for selecting the IDLE thread body is: |
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297 | * |
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298 | * 1. BSP provided |
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299 | * 2. CPU dependent (if provided) |
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300 | * 3. generic (if no BSP and no CPU dependent) |
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301 | * |
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302 | * AVR Specific Information: |
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303 | * |
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304 | * XXX document implementation including references if appropriate |
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305 | */ |
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306 | |
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307 | #define CPU_PROVIDES_IDLE_THREAD_BODY TRUE |
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308 | |
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309 | /* |
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310 | * Does the stack grow up (toward higher addresses) or down |
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311 | * (toward lower addresses)? |
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312 | * |
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313 | * If TRUE, then the grows upward. |
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314 | * If FALSE, then the grows toward smaller addresses. |
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315 | * |
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316 | * AVR Specific Information: |
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317 | * |
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318 | * XXX document implementation including references if appropriate |
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319 | */ |
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320 | |
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321 | #define CPU_STACK_GROWS_UP FALSE |
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322 | |
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323 | /* |
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324 | * The following is the variable attribute used to force alignment |
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325 | * of critical RTEMS structures. On some processors it may make |
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326 | * sense to have these aligned on tighter boundaries than |
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327 | * the minimum requirements of the compiler in order to have as |
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328 | * much of the critical data area as possible in a cache line. |
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329 | * |
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330 | * The placement of this macro in the declaration of the variables |
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331 | * is based on the syntactically requirements of the GNU C |
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332 | * "__attribute__" extension. For example with GNU C, use |
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333 | * the following to force a structures to a 32 byte boundary. |
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334 | * |
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335 | * __attribute__ ((aligned (32))) |
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336 | * |
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337 | * NOTE: Currently only the Priority Bit Map table uses this feature. |
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338 | * To benefit from using this, the data must be heavily |
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339 | * used so it will stay in the cache and used frequently enough |
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340 | * in the executive to justify turning this on. |
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341 | * |
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342 | * AVR Specific Information: |
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343 | * |
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344 | * XXX document implementation including references if appropriate |
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345 | */ |
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346 | |
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347 | #define CPU_STRUCTURE_ALIGNMENT |
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348 | |
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349 | #define CPU_TIMESTAMP_USE_STRUCT_TIMESPEC TRUE |
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350 | |
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351 | /* |
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352 | * Define what is required to specify how the network to host conversion |
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353 | * routines are handled. |
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354 | * |
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355 | * AVR Specific Information: |
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356 | * |
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357 | * XXX document implementation including references if appropriate |
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358 | */ |
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359 | |
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360 | #define CPU_BIG_ENDIAN TRUE |
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361 | #define CPU_LITTLE_ENDIAN FALSE |
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362 | |
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363 | /* |
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364 | * The following defines the number of bits actually used in the |
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365 | * interrupt field of the task mode. How those bits map to the |
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366 | * CPU interrupt levels is defined by the routine _CPU_ISR_Set_level(). |
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367 | * |
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368 | * AVR Specific Information: |
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369 | * |
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370 | * XXX document implementation including references if appropriate |
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371 | */ |
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372 | |
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373 | #define CPU_MODES_INTERRUPT_MASK 0x00000001 |
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374 | |
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375 | /* |
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376 | * Processor defined structures required for cpukit/score. |
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377 | * |
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378 | * AVR Specific Information: |
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379 | * |
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380 | * XXX document implementation including references if appropriate |
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381 | */ |
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382 | |
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383 | /* may need to put some structures here. */ |
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384 | |
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385 | #ifndef ASM |
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386 | |
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387 | /* |
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388 | * Contexts |
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389 | * |
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390 | * Generally there are 2 types of context to save. |
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391 | * 1. Interrupt registers to save |
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392 | * 2. Task level registers to save |
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393 | * |
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394 | * This means we have the following 3 context items: |
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395 | * 1. task level context stuff:: Context_Control |
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396 | * 2. floating point task stuff:: Context_Control_fp |
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397 | * 3. special interrupt level context :: Context_Control_interrupt |
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398 | * |
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399 | * On some processors, it is cost-effective to save only the callee |
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400 | * preserved registers during a task context switch. This means |
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401 | * that the ISR code needs to save those registers which do not |
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402 | * persist across function calls. It is not mandatory to make this |
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403 | * distinctions between the caller/callee saves registers for the |
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404 | * purpose of minimizing context saved during task switch and on interrupts. |
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405 | * If the cost of saving extra registers is minimal, simplicity is the |
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406 | * choice. Save the same context on interrupt entry as for tasks in |
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407 | * this case. |
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408 | * |
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409 | * Additionally, if gdb is to be made aware of RTEMS tasks for this CPU, then |
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410 | * care should be used in designing the context area. |
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411 | * |
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412 | * On some CPUs with hardware floating point support, the Context_Control_fp |
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413 | * structure will not be used or it simply consist of an array of a |
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414 | * fixed number of bytes. This is done when the floating point context |
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415 | * is dumped by a "FP save context" type instruction and the format |
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416 | * is not really defined by the CPU. In this case, there is no need |
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417 | * to figure out the exact format -- only the size. Of course, although |
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418 | * this is enough information for RTEMS, it is probably not enough for |
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419 | * a debugger such as gdb. But that is another problem. |
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420 | * |
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421 | * AVR Specific Information: |
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422 | * |
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423 | * XXX document implementation including references if appropriate |
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424 | */ |
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425 | |
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426 | typedef struct { |
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427 | uint16_t stack_pointer; |
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428 | uint8_t status; /* SREG */ |
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429 | } Context_Control; |
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430 | |
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431 | #define _CPU_Context_Get_SP( _context ) \ |
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432 | (_context)->stack_pointer |
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433 | |
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434 | |
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435 | |
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436 | |
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437 | typedef struct { |
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438 | double some_float_register; |
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439 | } Context_Control_fp; |
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440 | |
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441 | typedef struct { |
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442 | uint32_t special_interrupt_register; |
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443 | } CPU_Interrupt_frame; |
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444 | |
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445 | /* |
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446 | * This variable is optional. It is used on CPUs on which it is difficult |
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447 | * to generate an "uninitialized" FP context. It is filled in by |
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448 | * _CPU_Initialize and copied into the task's FP context area during |
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449 | * _CPU_Context_Initialize. |
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450 | * |
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451 | * AVR Specific Information: |
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452 | * |
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453 | * XXX document implementation including references if appropriate |
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454 | */ |
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455 | |
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456 | SCORE_EXTERN Context_Control_fp _CPU_Null_fp_context; |
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457 | |
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458 | #endif /* ASM */ |
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459 | |
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460 | /* |
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461 | * Nothing prevents the porter from declaring more CPU specific variables. |
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462 | * |
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463 | * AVR Specific Information: |
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464 | * |
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465 | * XXX document implementation including references if appropriate |
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466 | */ |
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467 | |
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468 | /* XXX: if needed, put more variables here */ |
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469 | |
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470 | /* |
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471 | * The size of the floating point context area. On some CPUs this |
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472 | * will not be a "sizeof" because the format of the floating point |
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473 | * area is not defined -- only the size is. This is usually on |
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474 | * CPUs with a "floating point save context" instruction. |
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475 | * |
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476 | * AVR Specific Information: |
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477 | * |
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478 | * XXX document implementation including references if appropriate |
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479 | */ |
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480 | |
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481 | #define CPU_CONTEXT_FP_SIZE sizeof( Context_Control_fp ) |
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482 | |
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483 | /* |
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484 | * Amount of extra stack (above minimum stack size) required by |
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485 | * MPCI receive server thread. Remember that in a multiprocessor |
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486 | * system this thread must exist and be able to process all directives. |
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487 | * |
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488 | * AVR Specific Information: |
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489 | * |
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490 | * XXX document implementation including references if appropriate |
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491 | */ |
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492 | |
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493 | #define CPU_MPCI_RECEIVE_SERVER_EXTRA_STACK 0 |
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494 | |
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495 | /* |
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496 | * This defines the number of entries in the ISR_Vector_table managed |
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497 | * by RTEMS. |
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498 | * |
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499 | * AVR Specific Information: |
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500 | * |
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501 | * XXX document implementation including references if appropriate |
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502 | */ |
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503 | |
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504 | #define CPU_INTERRUPT_NUMBER_OF_VECTORS 32 |
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505 | #define CPU_INTERRUPT_MAXIMUM_VECTOR_NUMBER (CPU_INTERRUPT_NUMBER_OF_VECTORS - 1) |
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506 | |
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507 | /* |
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508 | * This is defined if the port has a special way to report the ISR nesting |
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509 | * level. Most ports maintain the variable _ISR_Nest_level. |
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510 | */ |
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511 | |
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512 | #define CPU_PROVIDES_ISR_IS_IN_PROGRESS FALSE |
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513 | |
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514 | /* |
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515 | * Should be large enough to run all RTEMS tests. This ensures |
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516 | * that a "reasonable" small application should not have any problems. |
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517 | * |
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518 | * AVR Specific Information: |
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519 | * |
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520 | * XXX document implementation including references if appropriate |
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521 | */ |
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522 | |
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523 | #define CPU_STACK_MINIMUM_SIZE 512 |
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524 | |
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525 | /* |
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526 | * Maximum priority of a thread. Note based from 0 which is the idle task. |
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527 | */ |
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528 | #define CPU_PRIORITY_MAXIMUM 15 |
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529 | |
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530 | #define CPU_SIZEOF_POINTER 2 |
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531 | |
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532 | /* |
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533 | * CPU's worst alignment requirement for data types on a byte boundary. This |
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534 | * alignment does not take into account the requirements for the stack. |
---|
535 | * |
---|
536 | * AVR Specific Information: |
---|
537 | * |
---|
538 | * XXX document implementation including references if appropriate |
---|
539 | */ |
---|
540 | |
---|
541 | #define CPU_ALIGNMENT 4 |
---|
542 | |
---|
543 | /* |
---|
544 | * This number corresponds to the byte alignment requirement for the |
---|
545 | * heap handler. This alignment requirement may be stricter than that |
---|
546 | * for the data types alignment specified by CPU_ALIGNMENT. It is |
---|
547 | * common for the heap to follow the same alignment requirement as |
---|
548 | * CPU_ALIGNMENT. If the CPU_ALIGNMENT is strict enough for the heap, |
---|
549 | * then this should be set to CPU_ALIGNMENT. |
---|
550 | * |
---|
551 | * NOTE: This does not have to be a power of 2 although it should be |
---|
552 | * a multiple of 2 greater than or equal to 2. The requirement |
---|
553 | * to be a multiple of 2 is because the heap uses the least |
---|
554 | * significant field of the front and back flags to indicate |
---|
555 | * that a block is in use or free. So you do not want any odd |
---|
556 | * length blocks really putting length data in that bit. |
---|
557 | * |
---|
558 | * On byte oriented architectures, CPU_HEAP_ALIGNMENT normally will |
---|
559 | * have to be greater or equal to than CPU_ALIGNMENT to ensure that |
---|
560 | * elements allocated from the heap meet all restrictions. |
---|
561 | * |
---|
562 | * AVR Specific Information: |
---|
563 | * |
---|
564 | * XXX document implementation including references if appropriate |
---|
565 | */ |
---|
566 | |
---|
567 | #define CPU_HEAP_ALIGNMENT CPU_ALIGNMENT |
---|
568 | |
---|
569 | /* |
---|
570 | * This number corresponds to the byte alignment requirement for memory |
---|
571 | * buffers allocated by the partition manager. This alignment requirement |
---|
572 | * may be stricter than that for the data types alignment specified by |
---|
573 | * CPU_ALIGNMENT. It is common for the partition to follow the same |
---|
574 | * alignment requirement as CPU_ALIGNMENT. If the CPU_ALIGNMENT is strict |
---|
575 | * enough for the partition, then this should be set to CPU_ALIGNMENT. |
---|
576 | * |
---|
577 | * NOTE: This does not have to be a power of 2. It does have to |
---|
578 | * be greater or equal to than CPU_ALIGNMENT. |
---|
579 | * |
---|
580 | * AVR Specific Information: |
---|
581 | * |
---|
582 | * XXX document implementation including references if appropriate |
---|
583 | */ |
---|
584 | |
---|
585 | #define CPU_PARTITION_ALIGNMENT CPU_ALIGNMENT |
---|
586 | |
---|
587 | /* |
---|
588 | * This number corresponds to the byte alignment requirement for the |
---|
589 | * stack. This alignment requirement may be stricter than that for the |
---|
590 | * data types alignment specified by CPU_ALIGNMENT. If the CPU_ALIGNMENT |
---|
591 | * is strict enough for the stack, then this should be set to 0. |
---|
592 | * |
---|
593 | * NOTE: This must be a power of 2 either 0 or greater than CPU_ALIGNMENT. |
---|
594 | * |
---|
595 | * AVR Specific Information: |
---|
596 | * |
---|
597 | * XXX document implementation including references if appropriate |
---|
598 | */ |
---|
599 | |
---|
600 | #define CPU_STACK_ALIGNMENT 0 |
---|
601 | |
---|
602 | /* |
---|
603 | * ISR handler macros |
---|
604 | */ |
---|
605 | |
---|
606 | /* |
---|
607 | * Support routine to initialize the RTEMS vector table after it is allocated. |
---|
608 | * |
---|
609 | * AVR Specific Information: |
---|
610 | * |
---|
611 | * XXX document implementation including references if appropriate |
---|
612 | */ |
---|
613 | |
---|
614 | #define _CPU_Initialize_vectors() |
---|
615 | |
---|
616 | /* |
---|
617 | * Disable all interrupts for an RTEMS critical section. The previous |
---|
618 | * level is returned in _level. |
---|
619 | * |
---|
620 | * AVR Specific Information: |
---|
621 | * |
---|
622 | * XXX document implementation including references if appropriate |
---|
623 | */ |
---|
624 | |
---|
625 | #define _CPU_ISR_Disable( _isr_cookie ) \ |
---|
626 | do { \ |
---|
627 | (_isr_cookie) = SREG; \ |
---|
628 | __asm__ volatile ("cli"::); \ |
---|
629 | } while (0) |
---|
630 | |
---|
631 | /* |
---|
632 | * Enable interrupts to the previous level (returned by _CPU_ISR_Disable). |
---|
633 | * This indicates the end of an RTEMS critical section. The parameter |
---|
634 | * _level is not modified. |
---|
635 | * |
---|
636 | * AVR Specific Information: |
---|
637 | * |
---|
638 | * XXX document implementation including references if appropriate |
---|
639 | */ |
---|
640 | |
---|
641 | #define _CPU_ISR_Enable( _isr_cookie ) \ |
---|
642 | do { \ |
---|
643 | SREG = _isr_cookie; \ |
---|
644 | __asm__ volatile ("sei"::); \ |
---|
645 | } while (0) |
---|
646 | |
---|
647 | /* |
---|
648 | * This temporarily restores the interrupt to _level before immediately |
---|
649 | * disabling them again. This is used to divide long RTEMS critical |
---|
650 | * sections into two or more parts. The parameter _level is not |
---|
651 | * modified. |
---|
652 | * |
---|
653 | * AVR Specific Information: |
---|
654 | * |
---|
655 | * XXX document implementation including references if appropriate |
---|
656 | */ |
---|
657 | |
---|
658 | #define _CPU_ISR_Flash( _isr_cookie ) \ |
---|
659 | do { \ |
---|
660 | SREG=(_isr_cookie); \ |
---|
661 | __asm__ volatile("sei"::); \ |
---|
662 | (_isr_cookie) = SREG; \ |
---|
663 | __asm__ volatile("cli"::); \ |
---|
664 | } while (0) |
---|
665 | |
---|
666 | /* |
---|
667 | * Map interrupt level in task mode onto the hardware that the CPU |
---|
668 | * actually provides. Currently, interrupt levels which do not |
---|
669 | * map onto the CPU in a generic fashion are undefined. Someday, |
---|
670 | * it would be nice if these were "mapped" by the application |
---|
671 | * via a callout. For example, m68k has 8 levels 0 - 7, levels |
---|
672 | * 8 - 255 would be available for bsp/application specific meaning. |
---|
673 | * This could be used to manage a programmable interrupt controller |
---|
674 | * via the rtems_task_mode directive. |
---|
675 | * |
---|
676 | * The get routine usually must be implemented as a subroutine. |
---|
677 | * |
---|
678 | * AVR Specific Information: |
---|
679 | * |
---|
680 | * XXX document implementation including references if appropriate |
---|
681 | */ |
---|
682 | |
---|
683 | #define _CPU_ISR_Set_level( new_level ) \ |
---|
684 | { \ |
---|
685 | } |
---|
686 | |
---|
687 | #ifndef ASM |
---|
688 | |
---|
689 | uint32_t _CPU_ISR_Get_level( void ); |
---|
690 | |
---|
691 | /* end of ISR handler macros */ |
---|
692 | |
---|
693 | /* Context handler macros */ |
---|
694 | |
---|
695 | /* |
---|
696 | * Initialize the context to a state suitable for starting a |
---|
697 | * task after a context restore operation. Generally, this |
---|
698 | * involves: |
---|
699 | * |
---|
700 | * - setting a starting address |
---|
701 | * - preparing the stack |
---|
702 | * - preparing the stack and frame pointers |
---|
703 | * - setting the proper interrupt level in the context |
---|
704 | * - initializing the floating point context |
---|
705 | * |
---|
706 | * This routine generally does not set any unnecessary register |
---|
707 | * in the context. The state of the "general data" registers is |
---|
708 | * undefined at task start time. |
---|
709 | * |
---|
710 | * NOTE: This is_fp parameter is TRUE if the thread is to be a floating |
---|
711 | * point thread. This is typically only used on CPUs where the |
---|
712 | * FPU may be easily disabled by software such as on the SPARC |
---|
713 | * where the PSR contains an enable FPU bit. |
---|
714 | * |
---|
715 | * AVR Specific Information: |
---|
716 | * |
---|
717 | * XXX document implementation including references if appropriate |
---|
718 | */ |
---|
719 | /* |
---|
720 | #define _CPU_Context_Initialize( _the_context, _stack_base, _size, \ |
---|
721 | _isr, _entry_point, _is_fp ) \ |
---|
722 | \ |
---|
723 | do { \ |
---|
724 | uint16_t *_stack;\ |
---|
725 | _stack = (uint16_t) (_stack_base) + (uint16_t)(_size);\ |
---|
726 | (_the_context)->stack_pointer = _stack-1; \ |
---|
727 | *(_stack) = *(_entry_point); \ |
---|
728 | printk("the ret address is %x\n", *(uint16_t *)(_stack));\ |
---|
729 | printk("sp = 0x%x\nep = 0x%x\n",_stack, *(_entry_point)); \ |
---|
730 | printk("stack base = 0x%x\n size = 0x%x\n",_stack_base, _size);\ |
---|
731 | printk("struct starting address = 0x%x\n", _the_context);\ |
---|
732 | printk("struct stack pointer address = 0x%x\n",(_the_context)->stack_pointer);\ |
---|
733 | } while ( 0 ) |
---|
734 | |
---|
735 | */ |
---|
736 | /* |
---|
737 | * This routine is responsible for somehow restarting the currently |
---|
738 | * executing task. If you are lucky, then all that is necessary |
---|
739 | * is restoring the context. Otherwise, there will need to be |
---|
740 | * a special assembly routine which does something special in this |
---|
741 | * case. Context_Restore should work most of the time. It will |
---|
742 | * not work if restarting self conflicts with the stack frame |
---|
743 | * assumptions of restoring a context. |
---|
744 | * |
---|
745 | * AVR Specific Information: |
---|
746 | * |
---|
747 | * XXX document implementation including references if appropriate |
---|
748 | */ |
---|
749 | |
---|
750 | #define _CPU_Context_Restart_self( _the_context ) \ |
---|
751 | _CPU_Context_restore( _the_context ); |
---|
752 | |
---|
753 | /* |
---|
754 | * The purpose of this macro is to allow the initial pointer into |
---|
755 | * a floating point context area (used to save the floating point |
---|
756 | * context) to be at an arbitrary place in the floating point |
---|
757 | * context area. |
---|
758 | * |
---|
759 | * This is necessary because some FP units are designed to have |
---|
760 | * their context saved as a stack which grows into lower addresses. |
---|
761 | * Other FP units can be saved by simply moving registers into offsets |
---|
762 | * from the base of the context area. Finally some FP units provide |
---|
763 | * a "dump context" instruction which could fill in from high to low |
---|
764 | * or low to high based on the whim of the CPU designers. |
---|
765 | * |
---|
766 | * AVR Specific Information: |
---|
767 | * |
---|
768 | * XXX document implementation including references if appropriate |
---|
769 | */ |
---|
770 | |
---|
771 | #define _CPU_Context_Fp_start( _base, _offset ) \ |
---|
772 | ( (void *) _Addresses_Add_offset( (_base), (_offset) ) ) |
---|
773 | |
---|
774 | /* |
---|
775 | * This routine initializes the FP context area passed to it to. |
---|
776 | * There are a few standard ways in which to initialize the |
---|
777 | * floating point context. The code included for this macro assumes |
---|
778 | * that this is a CPU in which a "initial" FP context was saved into |
---|
779 | * _CPU_Null_fp_context and it simply copies it to the destination |
---|
780 | * context passed to it. |
---|
781 | * |
---|
782 | * Other models include (1) not doing anything, and (2) putting |
---|
783 | * a "null FP status word" in the correct place in the FP context. |
---|
784 | * |
---|
785 | * AVR Specific Information: |
---|
786 | * |
---|
787 | * XXX document implementation including references if appropriate |
---|
788 | */ |
---|
789 | |
---|
790 | #define _CPU_Context_Initialize_fp( _destination ) \ |
---|
791 | { \ |
---|
792 | *(*(_destination)) = _CPU_Null_fp_context; \ |
---|
793 | } |
---|
794 | |
---|
795 | /* end of Context handler macros */ |
---|
796 | |
---|
797 | /* Fatal Error manager macros */ |
---|
798 | |
---|
799 | /* |
---|
800 | * This routine copies _error into a known place -- typically a stack |
---|
801 | * location or a register, optionally disables interrupts, and |
---|
802 | * halts/stops the CPU. |
---|
803 | * |
---|
804 | * AVR Specific Information: |
---|
805 | * |
---|
806 | * XXX document implementation including references if appropriate |
---|
807 | */ |
---|
808 | |
---|
809 | #define _CPU_Fatal_halt( _error ) \ |
---|
810 | { \ |
---|
811 | } |
---|
812 | |
---|
813 | /* end of Fatal Error manager macros */ |
---|
814 | |
---|
815 | /* Bitfield handler macros */ |
---|
816 | |
---|
817 | /* |
---|
818 | * This routine sets _output to the bit number of the first bit |
---|
819 | * set in _value. _value is of CPU dependent type Priority_bit_map_Control. |
---|
820 | * This type may be either 16 or 32 bits wide although only the 16 |
---|
821 | * least significant bits will be used. |
---|
822 | * |
---|
823 | * There are a number of variables in using a "find first bit" type |
---|
824 | * instruction. |
---|
825 | * |
---|
826 | * (1) What happens when run on a value of zero? |
---|
827 | * (2) Bits may be numbered from MSB to LSB or vice-versa. |
---|
828 | * (3) The numbering may be zero or one based. |
---|
829 | * (4) The "find first bit" instruction may search from MSB or LSB. |
---|
830 | * |
---|
831 | * RTEMS guarantees that (1) will never happen so it is not a concern. |
---|
832 | * (2),(3), (4) are handled by the macros _CPU_Priority_mask() and |
---|
833 | * _CPU_Priority_bits_index(). These three form a set of routines |
---|
834 | * which must logically operate together. Bits in the _value are |
---|
835 | * set and cleared based on masks built by _CPU_Priority_mask(). |
---|
836 | * The basic major and minor values calculated by _Priority_Major() |
---|
837 | * and _Priority_Minor() are "massaged" by _CPU_Priority_bits_index() |
---|
838 | * to properly range between the values returned by the "find first bit" |
---|
839 | * instruction. This makes it possible for _Priority_Get_highest() to |
---|
840 | * calculate the major and directly index into the minor table. |
---|
841 | * This mapping is necessary to ensure that 0 (a high priority major/minor) |
---|
842 | * is the first bit found. |
---|
843 | * |
---|
844 | * This entire "find first bit" and mapping process depends heavily |
---|
845 | * on the manner in which a priority is broken into a major and minor |
---|
846 | * components with the major being the 4 MSB of a priority and minor |
---|
847 | * the 4 LSB. Thus (0 << 4) + 0 corresponds to priority 0 -- the highest |
---|
848 | * priority. And (15 << 4) + 14 corresponds to priority 254 -- the next |
---|
849 | * to the lowest priority. |
---|
850 | * |
---|
851 | * If your CPU does not have a "find first bit" instruction, then |
---|
852 | * there are ways to make do without it. Here are a handful of ways |
---|
853 | * to implement this in software: |
---|
854 | * |
---|
855 | * - a series of 16 bit test instructions |
---|
856 | * - a "binary search using if's" |
---|
857 | * - _number = 0 |
---|
858 | * if _value > 0x00ff |
---|
859 | * _value >>=8 |
---|
860 | * _number = 8; |
---|
861 | * |
---|
862 | * if _value > 0x0000f |
---|
863 | * _value >=8 |
---|
864 | * _number += 4 |
---|
865 | * |
---|
866 | * _number += bit_set_table[ _value ] |
---|
867 | * |
---|
868 | * where bit_set_table[ 16 ] has values which indicate the first |
---|
869 | * bit set |
---|
870 | * |
---|
871 | * AVR Specific Information: |
---|
872 | * |
---|
873 | * XXX document implementation including references if appropriate |
---|
874 | */ |
---|
875 | |
---|
876 | #define CPU_USE_GENERIC_BITFIELD_CODE TRUE |
---|
877 | #define CPU_USE_GENERIC_BITFIELD_DATA TRUE |
---|
878 | |
---|
879 | #if (CPU_USE_GENERIC_BITFIELD_CODE == FALSE) |
---|
880 | |
---|
881 | #define _CPU_Bitfield_Find_first_bit( _value, _output ) \ |
---|
882 | { \ |
---|
883 | (_output) = 0; /* do something to prevent warnings */ \ |
---|
884 | } |
---|
885 | |
---|
886 | #endif |
---|
887 | |
---|
888 | /* end of Bitfield handler macros */ |
---|
889 | |
---|
890 | /* |
---|
891 | * This routine builds the mask which corresponds to the bit fields |
---|
892 | * as searched by _CPU_Bitfield_Find_first_bit(). See the discussion |
---|
893 | * for that routine. |
---|
894 | * |
---|
895 | * AVR Specific Information: |
---|
896 | * |
---|
897 | * XXX document implementation including references if appropriate |
---|
898 | */ |
---|
899 | |
---|
900 | #if (CPU_USE_GENERIC_BITFIELD_CODE == FALSE) |
---|
901 | |
---|
902 | #define _CPU_Priority_Mask( _bit_number ) \ |
---|
903 | ( 1 << (_bit_number) ) |
---|
904 | |
---|
905 | #endif |
---|
906 | |
---|
907 | /* |
---|
908 | * This routine translates the bit numbers returned by |
---|
909 | * _CPU_Bitfield_Find_first_bit() into something suitable for use as |
---|
910 | * a major or minor component of a priority. See the discussion |
---|
911 | * for that routine. |
---|
912 | * |
---|
913 | * AVR Specific Information: |
---|
914 | * |
---|
915 | * XXX document implementation including references if appropriate |
---|
916 | */ |
---|
917 | |
---|
918 | #if (CPU_USE_GENERIC_BITFIELD_CODE == FALSE) |
---|
919 | |
---|
920 | #define _CPU_Priority_bits_index( _priority ) \ |
---|
921 | (_priority) |
---|
922 | |
---|
923 | #endif |
---|
924 | |
---|
925 | /* end of Priority handler macros */ |
---|
926 | |
---|
927 | /* functions */ |
---|
928 | |
---|
929 | /*context_initialize asm-function*/ |
---|
930 | |
---|
931 | void context_initialize(unsigned short* context, |
---|
932 | unsigned short stack_add, |
---|
933 | unsigned short entry_point); |
---|
934 | |
---|
935 | /* |
---|
936 | * _CPU_Context_Initialize |
---|
937 | * |
---|
938 | * This kernel routine initializes the basic non-FP context area associated |
---|
939 | * with each thread. |
---|
940 | * |
---|
941 | * Input parameters: |
---|
942 | * the_context - pointer to the context area |
---|
943 | * stack_base - address of memory for the SPARC |
---|
944 | * size - size in bytes of the stack area |
---|
945 | * new_level - interrupt level for this context area |
---|
946 | * entry_point - the starting execution point for this this context |
---|
947 | * is_fp - TRUE if this context is associated with an FP thread |
---|
948 | * |
---|
949 | * Output parameters: NONE |
---|
950 | */ |
---|
951 | |
---|
952 | void _CPU_Context_Initialize( |
---|
953 | Context_Control *the_context, |
---|
954 | uint32_t *stack_base, |
---|
955 | uint32_t size, |
---|
956 | uint32_t new_level, |
---|
957 | void *entry_point, |
---|
958 | bool is_fp |
---|
959 | ); |
---|
960 | |
---|
961 | /* |
---|
962 | * |
---|
963 | * _CPU_Push |
---|
964 | * |
---|
965 | * this routine pushes 2 bytes onto the stack |
---|
966 | * |
---|
967 | * |
---|
968 | * |
---|
969 | * |
---|
970 | * |
---|
971 | * |
---|
972 | * |
---|
973 | */ |
---|
974 | |
---|
975 | void _CPU_Push(uint16_t _SP_, uint16_t entry_point); |
---|
976 | |
---|
977 | |
---|
978 | |
---|
979 | |
---|
980 | /* |
---|
981 | * _CPU_Initialize |
---|
982 | * |
---|
983 | * This routine performs CPU dependent initialization. |
---|
984 | * |
---|
985 | * AVR Specific Information: |
---|
986 | * |
---|
987 | * XXX document implementation including references if appropriate |
---|
988 | */ |
---|
989 | |
---|
990 | void _CPU_Initialize(void); |
---|
991 | |
---|
992 | /* |
---|
993 | * _CPU_ISR_install_raw_handler |
---|
994 | * |
---|
995 | * This routine installs a "raw" interrupt handler directly into the |
---|
996 | * processor's vector table. |
---|
997 | * |
---|
998 | * AVR Specific Information: |
---|
999 | * |
---|
1000 | * XXX document implementation including references if appropriate |
---|
1001 | */ |
---|
1002 | |
---|
1003 | void _CPU_ISR_install_raw_handler( |
---|
1004 | uint32_t vector, |
---|
1005 | proc_ptr new_handler, |
---|
1006 | proc_ptr *old_handler |
---|
1007 | ); |
---|
1008 | |
---|
1009 | /* |
---|
1010 | * _CPU_ISR_install_vector |
---|
1011 | * |
---|
1012 | * This routine installs an interrupt vector. |
---|
1013 | * |
---|
1014 | * AVR Specific Information: |
---|
1015 | * |
---|
1016 | * XXX document implementation including references if appropriate |
---|
1017 | */ |
---|
1018 | |
---|
1019 | void _CPU_ISR_install_vector( |
---|
1020 | uint32_t vector, |
---|
1021 | proc_ptr new_handler, |
---|
1022 | proc_ptr *old_handler |
---|
1023 | ); |
---|
1024 | |
---|
1025 | /* |
---|
1026 | * _CPU_Install_interrupt_stack |
---|
1027 | * |
---|
1028 | * This routine installs the hardware interrupt stack pointer. |
---|
1029 | * |
---|
1030 | * NOTE: It need only be provided if CPU_HAS_HARDWARE_INTERRUPT_STACK |
---|
1031 | * is TRUE. |
---|
1032 | * |
---|
1033 | * AVR Specific Information: |
---|
1034 | * |
---|
1035 | * XXX document implementation including references if appropriate |
---|
1036 | */ |
---|
1037 | |
---|
1038 | void _CPU_Install_interrupt_stack( void ); |
---|
1039 | |
---|
1040 | /* |
---|
1041 | * _CPU_Thread_Idle_body |
---|
1042 | * |
---|
1043 | * This routine is the CPU dependent IDLE thread body. |
---|
1044 | * |
---|
1045 | * NOTE: It need only be provided if CPU_PROVIDES_IDLE_THREAD_BODY |
---|
1046 | * is TRUE. |
---|
1047 | * |
---|
1048 | * AVR Specific Information: |
---|
1049 | * |
---|
1050 | * XXX document implementation including references if appropriate |
---|
1051 | */ |
---|
1052 | |
---|
1053 | void *_CPU_Thread_Idle_body( uintptr_t ignored ); |
---|
1054 | |
---|
1055 | /* |
---|
1056 | * _CPU_Context_switch |
---|
1057 | * |
---|
1058 | * This routine switches from the run context to the heir context. |
---|
1059 | * |
---|
1060 | * AVR Specific Information: |
---|
1061 | * |
---|
1062 | * XXX document implementation including references if appropriate |
---|
1063 | */ |
---|
1064 | |
---|
1065 | void _CPU_Context_switch( |
---|
1066 | Context_Control *run, |
---|
1067 | Context_Control *heir |
---|
1068 | ); |
---|
1069 | |
---|
1070 | /* |
---|
1071 | * _CPU_Context_restore |
---|
1072 | * |
---|
1073 | * This routine is generally used only to restart self in an |
---|
1074 | * efficient manner. It may simply be a label in _CPU_Context_switch. |
---|
1075 | * |
---|
1076 | * NOTE: May be unnecessary to reload some registers. |
---|
1077 | * |
---|
1078 | * AVR Specific Information: |
---|
1079 | * |
---|
1080 | * XXX document implementation including references if appropriate |
---|
1081 | */ |
---|
1082 | |
---|
1083 | void _CPU_Context_restore( |
---|
1084 | Context_Control *new_context |
---|
1085 | ) RTEMS_COMPILER_NO_RETURN_ATTRIBUTE; |
---|
1086 | |
---|
1087 | /* |
---|
1088 | * _CPU_Context_save_fp |
---|
1089 | * |
---|
1090 | * This routine saves the floating point context passed to it. |
---|
1091 | * |
---|
1092 | * AVR Specific Information: |
---|
1093 | * |
---|
1094 | * XXX document implementation including references if appropriate |
---|
1095 | */ |
---|
1096 | |
---|
1097 | void _CPU_Context_save_fp( |
---|
1098 | Context_Control_fp **fp_context_ptr |
---|
1099 | ); |
---|
1100 | |
---|
1101 | /* |
---|
1102 | * _CPU_Context_restore_fp |
---|
1103 | * |
---|
1104 | * This routine restores the floating point context passed to it. |
---|
1105 | * |
---|
1106 | * AVR Specific Information: |
---|
1107 | * |
---|
1108 | * XXX document implementation including references if appropriate |
---|
1109 | */ |
---|
1110 | |
---|
1111 | void _CPU_Context_restore_fp( |
---|
1112 | Context_Control_fp **fp_context_ptr |
---|
1113 | ); |
---|
1114 | |
---|
1115 | /* FIXME */ |
---|
1116 | typedef CPU_Interrupt_frame CPU_Exception_frame; |
---|
1117 | |
---|
1118 | void _CPU_Exception_frame_print( const CPU_Exception_frame *frame ); |
---|
1119 | |
---|
1120 | /* The following routine swaps the endian format of an unsigned int. |
---|
1121 | * It must be static because it is referenced indirectly. |
---|
1122 | * |
---|
1123 | * This version will work on any processor, but if there is a better |
---|
1124 | * way for your CPU PLEASE use it. The most common way to do this is to: |
---|
1125 | * |
---|
1126 | * swap least significant two bytes with 16-bit rotate |
---|
1127 | * swap upper and lower 16-bits |
---|
1128 | * swap most significant two bytes with 16-bit rotate |
---|
1129 | * |
---|
1130 | * Some CPUs have special instructions which swap a 32-bit quantity in |
---|
1131 | * a single instruction (e.g. i486). It is probably best to avoid |
---|
1132 | * an "endian swapping control bit" in the CPU. One good reason is |
---|
1133 | * that interrupts would probably have to be disabled to ensure that |
---|
1134 | * an interrupt does not try to access the same "chunk" with the wrong |
---|
1135 | * endian. Another good reason is that on some CPUs, the endian bit |
---|
1136 | * endianness for ALL fetches -- both code and data -- so the code |
---|
1137 | * will be fetched incorrectly. |
---|
1138 | * |
---|
1139 | * AVR Specific Information: |
---|
1140 | * |
---|
1141 | * XXX document implementation including references if appropriate |
---|
1142 | */ |
---|
1143 | |
---|
1144 | static inline uint32_t CPU_swap_u32( |
---|
1145 | uint32_t value |
---|
1146 | ) |
---|
1147 | { |
---|
1148 | uint32_t byte1, byte2, byte3, byte4, swapped; |
---|
1149 | |
---|
1150 | byte4 = (value >> 24) & 0xff; |
---|
1151 | byte3 = (value >> 16) & 0xff; |
---|
1152 | byte2 = (value >> 8) & 0xff; |
---|
1153 | byte1 = value & 0xff; |
---|
1154 | |
---|
1155 | swapped = (byte1 << 24) | (byte2 << 16) | (byte3 << 8) | byte4; |
---|
1156 | return( swapped ); |
---|
1157 | } |
---|
1158 | |
---|
1159 | #define CPU_swap_u16( value ) \ |
---|
1160 | (((value&0xff) << 8) | ((value >> 8)&0xff)) |
---|
1161 | |
---|
1162 | #endif /* ASM */ |
---|
1163 | |
---|
1164 | #ifdef __cplusplus |
---|
1165 | } |
---|
1166 | #endif |
---|
1167 | |
---|
1168 | #endif |
---|