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   1 /*
   2  * Copyright © 2011 Keith Packard <keithp@keithp.com>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; version 2 of the License.
   7  *
   8  * This program is distributed in the hope that it will be useful, but
   9  * WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  16  */
  17
  18 #include "ao.h"
  19
  20 __xdata uint8_t ao_aes_mutex;
  21 __xdata uint8_t ao_aes_done;
  22 __xdata uint8_t ao_aes_dma_in, ao_aes_dma_out;
  23 __xdata uint8_t ao_aes_dma_in_done, ao_aes_dma_out_done;
  24 __pdata enum ao_aes_mode ao_aes_current_mode;
  25
  26 void
  27 ao_aes_isr(void) __interrupt 4
  28 {
  29         S0CON = 0;
  30         if (ENCCCS & ENCCCS_RDY) {
  31                 ao_aes_done = 1;
  32                 ao_wakeup(&ao_aes_done);
  33         }
  34 }
  35
  36 void
  37 ao_aes_set_mode(enum ao_aes_mode mode)
  38 {
  39         ao_aes_current_mode = mode;
  40 }
  41
  42 void
  43 ao_aes_set_key(__xdata uint8_t *in)
  44 {
  45         ao_dma_set_transfer(ao_aes_dma_in,
  46                             in,
  47                             &ENCDIXADDR,
  48                             7,
  49                             DMA_CFG0_WORDSIZE_8 |
  50                             DMA_CFG0_TMODE_SINGLE |
  51                             DMA_CFG0_TRIGGER_ENC_DW,
  52                             DMA_CFG1_SRCINC_1 |
  53                             DMA_CFG1_DESTINC_0 |
  54                             DMA_CFG1_PRIORITY_LOW);
  55         ao_aes_done = 0;
  56         ENCCCS = ENCCCS_MODE_CBC_MAC |
  57                 ENCCCS_CMD_LOAD_KEY |
  58                 ENCCCS_START;
  59         while (!ao_aes_done)
  60                 ao_sleep(&ao_aes_done);
  61 }
  62
  63 void
  64 ao_aes_run(__xdata uint8_t *in,
  65            __xdata uint8_t *out)
  66 {
  67         uint8_t b;
  68         if (in) {
  69                 ao_dma_set_transfer(ao_aes_dma_in,
  70                                     in,
  71                                     &ENCDIXADDR,
  72                                     7,
  73                                     DMA_CFG0_WORDSIZE_8 |
  74                                     DMA_CFG0_TMODE_SINGLE |
  75                                     DMA_CFG0_TRIGGER_ENC_DW,
  76                                     DMA_CFG1_SRCINC_1 |
  77                                     DMA_CFG1_DESTINC_0 |
  78                                     DMA_CFG1_PRIORITY_LOW);
  79         }
  80         if (out) {
  81                 ao_dma_set_transfer(ao_aes_dma_out,
  82                                     &ENCDOXADDR,
  83                                     out,
  84                                     7,
  85                                     DMA_CFG0_WORDSIZE_8 |
  86                                     DMA_CFG0_TMODE_SINGLE |
  87                                     DMA_CFG0_TRIGGER_ENC_UP,
  88                                     DMA_CFG1_SRCINC_0 |
  89                                     DMA_CFG1_DESTINC_1 |
  90                                     DMA_CFG1_PRIORITY_LOW);
  91         }
  92         switch (ao_aes_current_mode) {
  93         case ao_aes_mode_cbc_mac:
  94                 if (out)
  95                         b = (ENCCCS_MODE_CBC |
  96                              ENCCCS_CMD_ENCRYPT |
  97                              ENCCCS_START);
  98                 else
  99                         b = (ENCCCS_MODE_CBC_MAC |
 100                              ENCCCS_CMD_ENCRYPT |
 101                              ENCCCS_START);
 102                 break;
 103         default:
 104                 return;
 105         }
 106         ao_aes_done = 0;
 107         ENCCCS = b;
 108         if (out)
 109                 while (!ao_aes_dma_out_done)
 110                         ao_sleep(&ao_aes_dma_out_done);
 111         else
 112                 while (!ao_aes_done)
 113                         ao_sleep(&ao_aes_done);
 114 }
 115
 116 void
 117 ao_aes_init(void)
 118 {
 119         ao_aes_dma_in = ao_dma_alloc(&ao_aes_dma_in_done);
 120         ao_aes_dma_out = ao_dma_alloc(&ao_aes_dma_out_done);
 121         ENCIE = 1;
 122 }