firmware/target/arm/as3525/pcm-as3525.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright © 2008 Rafaël Carré
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
  16  *
  17  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  18  * KIND, either express or implied.
  19  *
  20  ****************************************************************************/
  21 #include "system.h"
  22 #include "audio.h"
  23 #include "string.h"
  24 #include "as3525.h"
  25 #include "pl081.h"
  26 #include "dma-target.h"
  27 #include "clock-target.h"
  28 #include "panic.h"
  29 #include "as3514.h"
  30 #include "audiohw.h"
  31
  32 #define MAX_TRANSFER (4*((1<<11)-1)) /* maximum data we can transfer via DMA
  33                                       * i.e. 32 bits at once (size of I2SO_DATA)
  34                                       * and the number of 32bits words has to
  35                                       * fit in 11 bits of DMA register */
  36
  37 static unsigned char *dma_start_addr;
  38 static size_t      dma_size;   /* in 4*32 bits */
  39 static void dma_callback(void);
  40 static int locked = 0;
  41
  42 /* Mask the DMA interrupt */
  43 void pcm_play_lock(void)
  44 {
  45     if(++locked == 1)
  46         VIC_INT_EN_CLEAR = INTERRUPT_DMAC;
  47 }
  48
  49 /* Unmask the DMA interrupt if enabled */
  50 void pcm_play_unlock(void)
  51 {
  52     if(--locked == 0)
  53         VIC_INT_ENABLE |= INTERRUPT_DMAC;
  54 }
  55
  56 static void play_start_pcm(void)
  57 {
  58     const unsigned char* addr = dma_start_addr;
  59     size_t size = dma_size;
  60     if(size > MAX_TRANSFER)
  61         size = MAX_TRANSFER;
  62
  63     if((unsigned int)dma_start_addr & 3)
  64         panicf("unaligned pointer!");
  65
  66     dma_size -= size;
  67     dma_start_addr += size;
  68
  69     CGU_PERI |= CGU_I2SOUT_APB_CLOCK_ENABLE;
  70     CGU_AUDIO |= (1<<11);
  71
  72     dma_enable_channel(1, (void*)addr, (void*)I2SOUT_DATA, DMA_PERI_I2SOUT,
  73                 DMAC_FLOWCTRL_DMAC_MEM_TO_PERI, true, false, size >> 2, DMA_S1,
  74                 dma_callback);
  75 }
  76
  77 static void dma_callback(void)
  78 {
  79     if(!dma_size)
  80     {
  81         register pcm_more_callback_type get_more = pcm_callback_for_more;
  82         if(get_more)
  83             get_more(&dma_start_addr, &dma_size);
  84     }
  85
  86     if(!dma_size)
  87         pcm_play_dma_stop();
  88     else
  89         play_start_pcm();
  90 }
  91
  92 void pcm_play_dma_start(const void *addr, size_t size)
  93 {
  94     dma_size = size;
  95     dma_start_addr = (unsigned char*)addr;
  96
  97     dma_retain();
  98
  99     play_start_pcm();
 100 }
 101
 102 void pcm_play_dma_stop(void)
 103 {
 104     dma_disable_channel(1);
 105     dma_size = 0;
 106
 107     dma_release();
 108
 109     CGU_PERI &= ~CGU_I2SOUT_APB_CLOCK_ENABLE;
 110     CGU_AUDIO &= ~(1<<11);
 111 }
 112
 113 void pcm_play_dma_pause(bool pause)
 114 {
 115     if(pause)
 116         dma_disable_channel(1);
 117     else
 118         play_start_pcm();
 119 }
 120
 121 void pcm_play_dma_init(void)
 122 {
 123     CGU_PERI |= CGU_I2SOUT_APB_CLOCK_ENABLE;
 124
 125     /* clock source PLLA, minimal frequency */
 126     CGU_AUDIO |= (511<<2) | (1<<0);
 127
 128     I2SOUT_CONTROL |= (1<<6) ;  /* enable dma */
 129     I2SOUT_CONTROL |= (1<<3) ;  /* stereo */
 130     I2SOUT_CONTROL &= ~(1<<2);  /* 16 bit samples */
 131
 132     audiohw_preinit();
 133 }
 134
 135 void pcm_postinit(void)
 136 {
 137     audiohw_postinit();
 138 }
 139
 140 void pcm_dma_apply_settings(void)
 141 {
 142     unsigned long frequency = pcm_sampr;
 143
 144     const int divider = (((AS3525_PLLA_FREQ/128) + (frequency/2)) / frequency) - 1;
 145     if(divider < 0 || divider > 511)
 146         panicf("unsupported frequency %ld", frequency);
 147
 148     CGU_AUDIO &= ~(((511 ^ divider) << 2) /* I2SOUT */
 149             /*| ((511 ^ divider) << 14) */ /* I2SIN */
 150             );
 151 }
 152
 153 size_t pcm_get_bytes_waiting(void)
 154 {
 155     return dma_size;
 156 }
 157
 158 const void * pcm_play_dma_get_peak_buffer(int *count)
 159 {
 160     *count = dma_size >> 2;
 161     return (const void*)dma_start_addr;
 162 }
 163
 164
 165 /****************************************************************************
 166  ** Recording DMA transfer
 167  **/
 168 #ifdef HAVE_RECORDING
 169 void pcm_rec_lock(void)
 170 {
 171 }
 172
 173 void pcm_rec_unlock(void)
 174 {
 175 }
 176
 177 void pcm_record_more(void *start, size_t size)
 178 {
 179     (void)start;
 180     (void)size;
 181 }
 182
 183 void pcm_rec_dma_stop(void)
 184 {
 185 }
 186
 187 void pcm_rec_dma_start(void *addr, size_t size)
 188 {
 189     (void)addr;
 190     (void)size;
 191 }
 192
 193 void pcm_rec_dma_close(void)
 194 {
 195 }
 196
 197
 198 void pcm_rec_dma_init(void)
 199 {
 200 }
 201
 202
 203 const void * pcm_rec_dma_get_peak_buffer(int *count)
 204 {
 205     (void)count;
 206 }
 207
 208 #endif /* HAVE_RECORDING */