1 | /////////////////////////////////////////////////////////////////////////////////// |
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2 | // File : dma_driver.c |
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3 | // Date : 23/11/2013 |
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4 | // Author : alain greiner |
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5 | // Copyright (c) UPMC-LIP6 |
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6 | /////////////////////////////////////////////////////////////////////////////////// |
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7 | // The dma_driver.c and dma_driver.h files are part ot the GIET-VM nano-kernel. |
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8 | // This driver supports the SoCLib vci_multi_dma component. |
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9 | // |
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10 | // It can exist several DMA controlers in the architecture (one per cluster), |
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11 | // and each controller can contain several channels. |
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12 | // |
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13 | // There is (NB_CLUSTERS * NB_DMA_CHANNELS) channels, indexed by a global index: |
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14 | // dma_id = cluster_xy * NB_DMA_CHANNELS + loc_id |
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15 | // |
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16 | // A DMA channel is a private ressource allocated to a given processor. |
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17 | // It is exclusively used by the kernet to speedup data transfers, and |
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18 | // there is no lock protecting exclusive access to the channel. |
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19 | // As the kernel uses a polling policy on the DMA_STATUS register to detect |
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20 | // transfer completion, the DMA IRQ is not used. |
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21 | // |
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22 | // The virtual base address of the segment associated to a channel is: |
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23 | // SEG_DMA_BASE + cluster_xy * PERI_CLUSTER_INCREMENT + DMA_SPAN * channel_id |
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24 | // |
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25 | // The SEG_DMA_BASE virtual address mus be defined in the hard_config.h file. |
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26 | //////////////////////////////////////////////////////////////////////////////////// |
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27 | |
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28 | #include <giet_config.h> |
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29 | #include <hard_config.h> |
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30 | #include <dma_driver.h> |
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31 | #include <tty_driver.h> |
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32 | #include <vmem.h> |
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33 | #include <utils.h> |
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34 | |
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35 | #if !defined(X_SIZE) |
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36 | # error: You must define X_SIZE in the hard_config.h file |
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37 | #endif |
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38 | |
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39 | #if !defined(Y_SIZE) |
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40 | # error: You must define X_SIZE in the hard_config.h file |
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41 | #endif |
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42 | |
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43 | #if !defined(X_WIDTH) |
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44 | # error: You must define X_WIDTH in the hard_config.h file |
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45 | #endif |
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46 | |
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47 | #if !defined(Y_WIDTH) |
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48 | # error: You must define X_WIDTH in the hard_config.h file |
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49 | #endif |
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50 | |
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51 | #if !defined(NB_DMA_CHANNELS) |
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52 | # error: You must define NB_DMA_CHANNELS in the hard_config.h file |
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53 | #endif |
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54 | |
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55 | #if !defined(SEG_DMA_BASE) |
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56 | # error: You must define SEG_DMA_BASE in the hard_config.h file |
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57 | #endif |
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58 | |
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59 | #if !defined(PERI_CLUSTER_INCREMENT) |
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60 | # error: You must define PERI_CLUSTER_INCREMENT in the hard_config.h file |
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61 | #endif |
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62 | |
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63 | extern unsigned int _ptabs_vaddr[]; |
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64 | |
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65 | ////////////////////////////////////////////////////////////////////////////////// |
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66 | // AS the GIET-VM uses a polling policy to detect transfer completion, |
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67 | // The DMA component initialisation must disable interrupts. |
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68 | // This function disables interrupts for one DMA channel in one cluster. |
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69 | // Returns 0 if success, returns > 0 if error. |
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70 | ////////////////////////////////////////////////////////////////////////////////// |
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71 | unsigned int _dma_init( unsigned int cluster_xy, |
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72 | unsigned int channel_id ) |
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73 | { |
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74 | #if NB_DMA_CHANNELS > 0 |
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75 | |
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76 | // parameters checking |
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77 | unsigned int x = cluster_xy >> Y_WIDTH; |
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78 | unsigned int y = cluster_xy & ((1<<Y_WIDTH)-1); |
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79 | if (x >= X_SIZE) return 1; |
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80 | if (y >= Y_SIZE) return 1; |
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81 | if (channel_id >= NB_DMA_CHANNELS) return 1; |
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82 | |
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83 | // compute DMA base address |
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84 | unsigned int* dma_address = (unsigned int*) ( SEG_DMA_BASE + |
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85 | (cluster_xy * PERI_CLUSTER_INCREMENT) ); |
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86 | |
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87 | // disable interrupt for selected channel |
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88 | dma_address[channel_id * DMA_SPAN + DMA_IRQ_DISABLE] = 1; |
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89 | return 0; |
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90 | #else |
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91 | return 1; |
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92 | #endif |
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93 | } |
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94 | |
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95 | ////////////////////////////////////////////////////////////////////////////////// |
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96 | // This function re-initialises one DMA channel in one cluster after a transfer |
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97 | // completion. It actually forces the channel to return in iDLE state. |
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98 | ////////////////////////////////////////////////////////////////////////////////// |
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99 | unsigned int _dma_reset( unsigned int cluster_xy, |
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100 | unsigned int channel_id ) |
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101 | { |
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102 | #if NB_DMA_CHANNELS > 0 |
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103 | |
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104 | // parameters checking |
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105 | unsigned int x = cluster_xy >> Y_WIDTH; |
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106 | unsigned int y = cluster_xy & ((1<<Y_WIDTH)-1); |
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107 | if (x >= X_SIZE) return 1; |
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108 | if (y >= Y_SIZE) return 1; |
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109 | if (channel_id >= NB_DMA_CHANNELS) return 1; |
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110 | |
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111 | // compute DMA base address |
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112 | unsigned int* dma_address = (unsigned int*) ( SEG_DMA_BASE + |
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113 | (cluster_xy * PERI_CLUSTER_INCREMENT) ); |
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114 | |
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115 | // reset selected channel |
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116 | dma_address[channel_id * DMA_SPAN + DMA_RESET] = 0; |
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117 | return 0; |
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118 | #else |
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119 | return 1; |
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120 | #endif |
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121 | } |
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122 | |
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123 | ////////////////////////////////////////////////////////////////////////////////// |
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124 | // This function returns the status of a DMA channel in a given cluster |
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125 | ////////////////////////////////////////////////////////////////////////////////// |
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126 | unsigned int _dma_get_status( unsigned int cluster_xy, |
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127 | unsigned int channel_id ) |
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128 | { |
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129 | #if NB_DMA_CHANNELS > 0 |
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130 | |
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131 | // parameters checking |
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132 | unsigned int x = cluster_xy >> Y_WIDTH; |
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133 | unsigned int y = cluster_xy & ((1<<Y_WIDTH)-1); |
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134 | if (x >= X_SIZE) return 1; |
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135 | if (y >= Y_SIZE) return 1; |
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136 | if (channel_id >= NB_DMA_CHANNELS) return 1; |
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137 | |
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138 | // compute DMA base address |
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139 | unsigned int * dma_address = (unsigned int *) ( SEG_DMA_BASE + |
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140 | (cluster_xy * PERI_CLUSTER_INCREMENT) ); |
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141 | |
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142 | // get selected channel status |
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143 | return dma_address[channel_id * DMA_SPAN + DMA_LEN]; |
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144 | #else |
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145 | return DMA_IDLE; |
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146 | #endif |
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147 | } |
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148 | |
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149 | ////////////////////////////////////////////////////////////////////////////////// |
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150 | // This function sets the physical address (including 64 bits extension) |
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151 | // for the source and destination buffers in a DMA channel in a given cluster |
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152 | // and sets the transfer size to lauch the transfer. |
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153 | ////////////////////////////////////////////////////////////////////////////////// |
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154 | void _dma_start_transfer( unsigned int cluster_xy, // DMA cluster |
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155 | unsigned int channel_id, // DMA channel |
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156 | unsigned long long dst_paddr, // physical address |
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157 | unsigned long long src_paddr, // physical address |
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158 | unsigned int size ) // bytes |
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159 | { |
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160 | #if NB_DMA_CHANNELS > 0 |
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161 | |
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162 | // compute DMA base address |
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163 | unsigned int * dma_address = (unsigned int *) ( SEG_DMA_BASE + |
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164 | (cluster_xy * PERI_CLUSTER_INCREMENT) ); |
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165 | |
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166 | // selected channel configuration and lauching |
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167 | dma_address[channel_id * DMA_SPAN + DMA_SRC] = (unsigned int)(src_paddr); |
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168 | dma_address[channel_id * DMA_SPAN + DMA_SRC_EXT] = (unsigned int)(src_paddr>>32); |
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169 | dma_address[channel_id * DMA_SPAN + DMA_DST] = (unsigned int)(dst_paddr); |
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170 | dma_address[channel_id * DMA_SPAN + DMA_DST_EXT] = (unsigned int)(dst_paddr>>32); |
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171 | dma_address[channel_id * DMA_SPAN + DMA_LEN] = (unsigned int)size; |
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172 | |
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173 | #endif |
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174 | } |
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175 | |
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176 | /////////////////////////////////////////////////////////////////////////////////// |
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177 | // This function copies a source memory buffer to a destination memory buffer, |
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178 | // using directly physical addresses. |
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179 | // This blocking function is supposed to be used by the kernel only, |
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180 | // and uses a polling policy on DMA_STATUS register to detect completion. |
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181 | // Therefore, the DMA_IRQ is NOT used. |
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182 | // The source and destination buffers base addresses must be word aligned, |
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183 | // and the buffer's size must be multiple of 4. |
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184 | // In case of error (buffer unmapped, unaligned, or DMA_STATUS error), an error |
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185 | // message is displayed on TTY0, and the system crash. |
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186 | /////////////////////////////////////////////////////////////////////////////////// |
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187 | void _dma_physical_copy( unsigned int cluster_xy, // DMA cluster |
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188 | unsigned int channel_id, // DMA channel |
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189 | unsigned long long dst_paddr, // destination physical address |
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190 | unsigned long long src_paddr, // source physical address |
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191 | unsigned int size ) // bytes |
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192 | { |
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193 | #if NB_DMA_CHANNELS > 0 |
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194 | |
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195 | // check DMA channel parameters |
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196 | unsigned int x = cluster_xy >> Y_WIDTH; |
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197 | unsigned int y = cluster_xy & ((1<<Y_WIDTH)-1); |
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198 | if ( (x >= X_SIZE) || (y >= Y_SIZE) || (channel_id >= NB_DMA_CHANNELS) ) |
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199 | { |
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200 | _printf("\n[GIET ERROR] in _dma_physical_copy() : illegal DMA channel "); |
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201 | _exit(); |
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202 | } |
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203 | |
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204 | // check buffers alignment constraints |
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205 | if ( (dst_paddr & 0x3) || (src_paddr & 0x3) || (size & 0x3) ) |
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206 | { |
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207 | _printf("\n[GIET ERROR] in _dma_physical_copy() : buffer unaligned\n"); |
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208 | _exit(); |
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209 | } |
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210 | |
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211 | #if GIET_DEBUG_DMA_DRIVER |
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212 | _printf("\n[DMA DEBUG] Start a dma_physical_copy on channel[%d,%d,%d] at cycle %d\n" |
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213 | " - src_paddr = %l\n" |
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214 | " - dst_paddr = %l\n" |
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215 | " - bytes = %x\n", |
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216 | x, y, channel_id, _get_proctime(), src_paddr, dst_paddr, size ); |
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217 | #endif |
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218 | |
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219 | // dma channel configuration & lauching |
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220 | _dma_start_transfer( cluster_xy, channel_id, dst_paddr, src_paddr, size ); |
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221 | |
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222 | // scan dma channel status |
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223 | unsigned int status = _dma_get_status( cluster_xy, channel_id ); |
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224 | while( (status != DMA_SUCCESS) && |
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225 | (status != DMA_READ_ERROR) && |
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226 | (status != DMA_WRITE_ERROR) ) |
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227 | { |
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228 | status = _dma_get_status( cluster_xy, channel_id ); |
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229 | |
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230 | #if GIET_DEBUG_DMA_DRIVER |
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231 | _printf("\n[DMA DEBUG] _dma_physical_copy() : ... waiting on DMA_STATUS register\n"); |
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232 | #endif |
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233 | |
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234 | } |
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235 | |
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236 | // analyse status |
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237 | if( status != DMA_SUCCESS ) |
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238 | { |
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239 | _printf("\n[GIET ERROR] in _dma_physical_copy() : DMA_STATUS = %x\n", status ); |
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240 | _exit(); |
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241 | } |
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242 | // reset dma channel |
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243 | _dma_reset( cluster_xy, channel_id ); |
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244 | |
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245 | #if GIET_DEBUG_DMA_DRIVER |
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246 | _printf("\n[DMA DEBUG] _dma_physical_copy() completed at cycle %d\n", _get_proctime() ); |
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247 | #endif |
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248 | |
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249 | #else // NB_DMA_CHANNELS == 0 |
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250 | _printf("\n[GIET ERROR] in _dma_physical_copy() : NB_DMA_CHANNELS == 0 / cycle %d\n", |
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251 | _get_proctime ); |
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252 | _exit(); |
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253 | #endif |
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254 | } |
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255 | |
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256 | /////////////////////////////////////////////////////////////////////////////////// |
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257 | // This function copies a source memory buffer to a destination memory buffer, |
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258 | // making virtual to physical address translation: the MMU should be activated. |
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259 | // This blocking function is supposed to be used by the kernel only, |
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260 | // and uses a polling policy on DMA_STATUS register to detect completion. |
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261 | // Therefore, the DMA_IRQ is NOT used. |
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262 | // The source and destination buffers base addresses must be word aligned, |
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263 | // and the buffer's size must be multiple of 4. |
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264 | // In case of error (buffer unmapped, unaligned, or DMA_STATUS error), an error |
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265 | // message is displayed on TTY0, and the system crash. |
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266 | /////////////////////////////////////////////////////////////////////////////////// |
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267 | void _dma_copy( unsigned int cluster_xy, // DMA cluster |
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268 | unsigned int channel_id, // DMA channel |
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269 | unsigned int vspace_id, // vspace index for v2p translation |
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270 | unsigned int dst_vaddr, // dst_vaddr buffer vbase |
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271 | unsigned int src_vaddr, // src_vaddr buffer vbase |
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272 | unsigned int size ) // bytes |
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273 | { |
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274 | #if NB_DMA_CHANNELS > 0 |
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275 | |
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276 | // check DMA channel parameters |
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277 | unsigned int x = cluster_xy >> Y_WIDTH; |
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278 | unsigned int y = cluster_xy & ((1<<Y_WIDTH)-1); |
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279 | if ( (x >= X_SIZE) || (y >= Y_SIZE) || (channel_id >= NB_DMA_CHANNELS) ) |
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280 | { |
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281 | _printf("\n[GIET ERROR] in _dma_copy() : illegal DMA channel "); |
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282 | _exit(); |
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283 | } |
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284 | |
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285 | // check buffers alignment constraints |
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286 | if ( (dst_vaddr & 0x3) || (src_vaddr & 0x3) || (size & 0x3) ) |
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287 | { |
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288 | _printf("\n[GIET ERROR] in _dma_copy() : buffer unaligned\n"); |
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289 | _exit(); |
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290 | } |
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291 | |
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292 | unsigned int ko; |
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293 | unsigned int ppn; |
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294 | unsigned int flags; |
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295 | |
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296 | #if GIET_DEBUG_DMA_DRIVER |
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297 | _printf("\n[DMA DEBUG] Start a dma_copy on channel[%d,%d,%d] at cycle %d\n" |
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298 | " - src_vaddr = %x\n" |
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299 | " - dst_vaddr = %x\n" |
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300 | " - bytes = %x\n", |
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301 | x, y, channel_id, _get_proctime(), src_vaddr, dst_vaddr, size ); |
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302 | #endif |
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303 | |
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304 | // checking alignment constraints |
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305 | if ( (((unsigned int)dst_vaddr) & 0x3) || |
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306 | (((unsigned int)src_vaddr) & 0x3) || |
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307 | (size & 0x3) ) |
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308 | { |
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309 | _printf("\n[GIET ERROR] in _dma_copy() : buffer unaligned\n"); |
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310 | _exit(); |
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311 | } |
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312 | |
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313 | // get vspace page table pointer |
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314 | unsigned int pt = _ptabs_vaddr[vspace_id]; |
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315 | |
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316 | // get src_paddr buffer physical addresse |
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317 | ko = _v2p_translate( (page_table_t*)pt, // page table pointer |
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318 | src_vaddr>>12, // vpn |
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319 | &ppn, // ppn |
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320 | &flags ); // flags |
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321 | if ( ko ) |
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322 | { |
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323 | _printf("\n[GIET ERROR] in _dma_copy() : source buffer unmapped\n"); |
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324 | _exit(); |
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325 | } |
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326 | unsigned long long src_paddr = (((unsigned long long)ppn) << 12) | |
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327 | (unsigned long long)(src_vaddr & 0x00000FFF); |
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328 | |
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329 | // get dst_paddr buffer physical addresse |
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330 | ko = _v2p_translate( (page_table_t*)pt, // page table pointer |
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331 | dst_vaddr>>12, // vpn |
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332 | &ppn, // ppn |
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333 | &flags ); // flags |
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334 | if ( ko ) |
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335 | { |
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336 | _printf("\n[GIET ERROR] in _dma_copy() : dest buffer unmapped\n"); |
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337 | _exit(); |
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338 | } |
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339 | unsigned long long dst_paddr = (((unsigned long long)ppn) << 12) | |
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340 | (unsigned long long)(dst_vaddr & 0x00000FFF); |
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341 | |
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342 | #if GIET_DEBUG_DMA_DRIVER |
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343 | _printf(" - src_paddr = %l\n" |
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344 | " - dst_paddr = %l\n", |
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345 | src_paddr, dst_paddr ); |
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346 | #endif |
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347 | |
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348 | // dma channel configuration & lauching |
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349 | _dma_start_transfer( cluster_xy, channel_id, dst_paddr, src_paddr, size ); |
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350 | |
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351 | // scan dma channel status |
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352 | unsigned int status = _dma_get_status( cluster_xy, channel_id ); |
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353 | while( (status != DMA_SUCCESS) && |
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354 | (status != DMA_READ_ERROR) && |
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355 | (status != DMA_WRITE_ERROR) ) |
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356 | { |
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357 | status = _dma_get_status( cluster_xy, channel_id ); |
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358 | |
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359 | #if GIET_DEBUG_DMA_DRIVER |
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360 | _printf("\n[DMA DEBUG] _dma_copy() : ... waiting on DMA_STATUS register\n"); |
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361 | #endif |
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362 | |
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363 | } |
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364 | |
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365 | // analyse status |
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366 | if( status != DMA_SUCCESS ) |
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367 | { |
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368 | _printf("\n[GIET ERROR] in _dma_copy() : DMA_STATUS = %x\n", status ); |
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369 | _exit(); |
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370 | } |
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371 | // reset dma channel |
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372 | _dma_reset( cluster_xy, channel_id ); |
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373 | |
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374 | #if GIET_DEBUG_DMA_DRIVER |
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375 | _printf("\n[DMA DEBUG] _dma_copy() completed at cycle %d\n", _get_proctime() ); |
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376 | #endif |
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377 | |
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378 | #else // NB_DMA_CHANNELS == 0 |
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379 | _printf("\n[GIET ERROR] in _dma_copy() : NB_DMA_CHANNELS == 0 / cycle %d\n", |
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380 | _get_proctime ); |
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381 | _exit(); |
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382 | #endif |
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383 | } // end _dma_copy |
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384 | |
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385 | /////////////////////////////////////////////////////////////////////////////// |
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386 | // This ISR handles the IRQ generated by a DMA channel. |
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387 | /////////////////////////////////////////////////////////////////////////////// |
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388 | void _dma_isr( unsigned int irq_type, |
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389 | unsigned int irq_id, |
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390 | unsigned int channel ) |
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391 | { |
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392 | _printf("\n[GIET ERROR] _dma_isr() not implemented / cycle %d\n", |
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393 | _get_proctime() ); |
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394 | _exit(); |
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395 | } |
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396 | |
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397 | |
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398 | |
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399 | |
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400 | // tab-width: 4 |
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401 | // c-basic-offset: 4 |
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402 | // c-file-offsets:((innamespace . 0)(inline-open . 0)) |
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403 | // indent-tabs-mode: nil |
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404 | // End: |
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405 | // vim: filetype=c:expandtab:shiftwidth=4:tabstop=4:softtabstop=4 |
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406 | |
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