hw/milkymist-ac97.c

   1 /*
   2  *  QEMU model of the Milkymist System Controller.
   3  *
   4  *  Copyright (c) 2010 Michael Walle <michael@walle.cc>
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  18  *
  19  *
  20  * Specification available at:
  21  *   http://www.milkymist.org/socdoc/ac97.pdf
  22  */
  23
  24 #include "hw.h"
  25 #include "sysbus.h"
  26 #include "trace.h"
  27 #include "audio/audio.h"
  28 #include "qemu-error.h"
  29
  30 enum {
  31     R_AC97_CTRL = 0,
  32     R_AC97_ADDR,
  33     R_AC97_DATAOUT,
  34     R_AC97_DATAIN,
  35     R_D_CTRL,
  36     R_D_ADDR,
  37     R_D_REMAINING,
  38     R_RESERVED,
  39     R_U_CTRL,
  40     R_U_ADDR,
  41     R_U_REMAINING,
  42     R_MAX
  43 };
  44
  45 enum {
  46     AC97_CTRL_RQEN  = (1<<0),
  47     AC97_CTRL_WRITE = (1<<1),
  48 };
  49
  50 enum {
  51     CTRL_EN = (1<<0),
  52 };
  53
  54 struct MilkymistAC97State {
  55     SysBusDevice busdev;
  56
  57     QEMUSoundCard card;
  58     SWVoiceIn *voice_in;
  59     SWVoiceOut *voice_out;
  60
  61     uint32_t regs[R_MAX];
  62
  63     qemu_irq crrequest_irq;
  64     qemu_irq crreply_irq;
  65     qemu_irq dmar_irq;
  66     qemu_irq dmaw_irq;
  67 };
  68 typedef struct MilkymistAC97State MilkymistAC97State;
  69
  70 static void update_voices(MilkymistAC97State *s)
  71 {
  72     if (s->regs[R_D_CTRL] & CTRL_EN) {
  73         AUD_set_active_out(s->voice_out, 1);
  74     } else {
  75         AUD_set_active_out(s->voice_out, 0);
  76     }
  77
  78     if (s->regs[R_U_CTRL] & CTRL_EN) {
  79         AUD_set_active_in(s->voice_in, 1);
  80     } else {
  81         AUD_set_active_in(s->voice_in, 0);
  82     }
  83 }
  84
  85 static uint32_t ac97_read(void *opaque, target_phys_addr_t addr)
  86 {
  87     MilkymistAC97State *s = opaque;
  88     uint32_t r = 0;
  89
  90     addr >>= 2;
  91     switch (addr) {
  92     case R_AC97_CTRL:
  93     case R_AC97_ADDR:
  94     case R_AC97_DATAOUT:
  95     case R_AC97_DATAIN:
  96     case R_D_CTRL:
  97     case R_D_ADDR:
  98     case R_D_REMAINING:
  99     case R_U_CTRL:
 100     case R_U_ADDR:
 101     case R_U_REMAINING:
 102         r = s->regs[addr];
 103         break;
 104
 105     default:
 106         error_report("milkymist_ac97: read access to unkown register 0x"
 107                 TARGET_FMT_plx, addr << 2);
 108         break;
 109     }
 110
 111     trace_milkymist_ac97_memory_read(addr << 2, r);
 112
 113     return r;
 114 }
 115
 116 static void ac97_write(void *opaque, target_phys_addr_t addr, uint32_t value)
 117 {
 118     MilkymistAC97State *s = opaque;
 119
 120     trace_milkymist_ac97_memory_write(addr, value);
 121
 122     addr >>= 2;
 123     switch (addr) {
 124     case R_AC97_CTRL:
 125         /* always raise an IRQ according to the direction */
 126         if (value & AC97_CTRL_RQEN) {
 127             if (value & AC97_CTRL_WRITE) {
 128                 trace_milkymist_ac97_pulse_irq_crrequest();
 129                 qemu_irq_pulse(s->crrequest_irq);
 130             } else {
 131                 trace_milkymist_ac97_pulse_irq_crreply();
 132                 qemu_irq_pulse(s->crreply_irq);
 133             }
 134         }
 135
 136         /* RQEN is self clearing */
 137         s->regs[addr] = value & ~AC97_CTRL_RQEN;
 138         break;
 139     case R_D_CTRL:
 140     case R_U_CTRL:
 141         s->regs[addr] = value;
 142         update_voices(s);
 143         break;
 144     case R_AC97_ADDR:
 145     case R_AC97_DATAOUT:
 146     case R_AC97_DATAIN:
 147     case R_D_ADDR:
 148     case R_D_REMAINING:
 149     case R_U_ADDR:
 150     case R_U_REMAINING:
 151         s->regs[addr] = value;
 152         break;
 153
 154     default:
 155         error_report("milkymist_ac97: write access to unkown register 0x"
 156                 TARGET_FMT_plx, addr);
 157         break;
 158     }
 159
 160 }
 161
 162 static CPUReadMemoryFunc * const ac97_read_fn[] = {
 163     NULL,
 164     NULL,
 165     &ac97_read,
 166 };
 167
 168 static CPUWriteMemoryFunc * const ac97_write_fn[] = {
 169     NULL,
 170     NULL,
 171     &ac97_write,
 172 };
 173
 174 static void ac97_in_cb(void *opaque, int avail_b)
 175 {
 176     MilkymistAC97State *s = opaque;
 177     uint8_t buf[4096];
 178     uint32_t remaining = s->regs[R_U_REMAINING];
 179     int temp = audio_MIN(remaining, avail_b);
 180     uint32_t addr = s->regs[R_U_ADDR];
 181     int transferred = 0;
 182
 183     trace_milkymist_ac97_in_cb(avail_b, remaining);
 184
 185     /* prevent from raising an IRQ */
 186     if (temp == 0) {
 187         return;
 188     }
 189
 190     while (temp) {
 191         int acquired, to_copy;
 192
 193         to_copy = audio_MIN(temp, sizeof(buf));
 194         acquired = AUD_read(s->voice_in, buf, to_copy);
 195         if (!acquired) {
 196             break;
 197         }
 198
 199         cpu_physical_memory_write(addr, buf, acquired);
 200
 201         temp -= acquired;
 202         addr += acquired;
 203         transferred += acquired;
 204     }
 205
 206     trace_milkymist_ac97_in_cb_transferred(transferred);
 207
 208     s->regs[R_U_ADDR] = addr;
 209     s->regs[R_U_REMAINING] -= transferred;
 210
 211     if ((s->regs[R_U_CTRL] & CTRL_EN) && (s->regs[R_U_REMAINING] == 0)) {
 212         trace_milkymist_ac97_pulse_irq_dmaw();
 213         qemu_irq_pulse(s->dmaw_irq);
 214     }
 215 }
 216
 217 static void ac97_out_cb(void *opaque, int free_b)
 218 {
 219     MilkymistAC97State *s = opaque;
 220     uint8_t buf[4096];
 221     uint32_t remaining = s->regs[R_D_REMAINING];
 222     int temp = audio_MIN(remaining, free_b);
 223     uint32_t addr = s->regs[R_D_ADDR];
 224     int transferred = 0;
 225
 226     trace_milkymist_ac97_out_cb(free_b, remaining);
 227
 228     /* prevent from raising an IRQ */
 229     if (temp == 0) {
 230         return;
 231     }
 232
 233     while (temp) {
 234         int copied, to_copy;
 235
 236         to_copy = audio_MIN(temp, sizeof(buf));
 237         cpu_physical_memory_read(addr, buf, to_copy);
 238         copied = AUD_write(s->voice_out, buf, to_copy);
 239         if (!copied) {
 240             break;
 241         }
 242         temp -= copied;
 243         addr += copied;
 244         transferred += copied;
 245     }
 246
 247     trace_milkymist_ac97_out_cb_transferred(transferred);
 248
 249     s->regs[R_D_ADDR] = addr;
 250     s->regs[R_D_REMAINING] -= transferred;
 251
 252     if ((s->regs[R_D_CTRL] & CTRL_EN) && (s->regs[R_D_REMAINING] == 0)) {
 253         trace_milkymist_ac97_pulse_irq_dmar();
 254         qemu_irq_pulse(s->dmar_irq);
 255     }
 256 }
 257
 258 static void milkymist_ac97_reset(DeviceState *d)
 259 {
 260     MilkymistAC97State *s = container_of(d, MilkymistAC97State, busdev.qdev);
 261     int i;
 262
 263     for (i = 0; i < R_MAX; i++) {
 264         s->regs[i] = 0;
 265     }
 266
 267     AUD_set_active_in(s->voice_in, 0);
 268     AUD_set_active_out(s->voice_out, 0);
 269 }
 270
 271 static int ac97_post_load(void *opaque, int version_id)
 272 {
 273     MilkymistAC97State *s = opaque;
 274
 275     update_voices(s);
 276
 277     return 0;
 278 }
 279
 280 static int milkymist_ac97_init(SysBusDevice *dev)
 281 {
 282     MilkymistAC97State *s = FROM_SYSBUS(typeof(*s), dev);
 283     int ac97_regs;
 284
 285     struct audsettings as;
 286     sysbus_init_irq(dev, &s->crrequest_irq);
 287     sysbus_init_irq(dev, &s->crreply_irq);
 288     sysbus_init_irq(dev, &s->dmar_irq);
 289     sysbus_init_irq(dev, &s->dmaw_irq);
 290
 291     AUD_register_card("Milkymist AC'97", &s->card);
 292
 293     as.freq = 48000;
 294     as.nchannels = 2;
 295     as.fmt = AUD_FMT_S16;
 296     as.endianness = 1;
 297
 298     s->voice_in = AUD_open_in(&s->card, s->voice_in,
 299             "mm_ac97.in", s, ac97_in_cb, &as);
 300     s->voice_out = AUD_open_out(&s->card, s->voice_out,
 301             "mm_ac97.out", s, ac97_out_cb, &as);
 302
 303     ac97_regs = cpu_register_io_memory(ac97_read_fn, ac97_write_fn, s,
 304             DEVICE_NATIVE_ENDIAN);
 305     sysbus_init_mmio(dev, R_MAX * 4, ac97_regs);
 306
 307     return 0;
 308 }
 309
 310 static const VMStateDescription vmstate_milkymist_ac97 = {
 311     .name = "milkymist-ac97",
 312     .version_id = 1,
 313     .minimum_version_id = 1,
 314     .minimum_version_id_old = 1,
 315     .post_load = ac97_post_load,
 316     .fields      = (VMStateField[]) {
 317         VMSTATE_UINT32_ARRAY(regs, MilkymistAC97State, R_MAX),
 318         VMSTATE_END_OF_LIST()
 319     }
 320 };
 321
 322 static SysBusDeviceInfo milkymist_ac97_info = {
 323     .init = milkymist_ac97_init,
 324     .qdev.name  = "milkymist-ac97",
 325     .qdev.size  = sizeof(MilkymistAC97State),
 326     .qdev.vmsd  = &vmstate_milkymist_ac97,
 327     .qdev.reset = milkymist_ac97_reset,
 328 };
 329
 330 static void milkymist_ac97_register(void)
 331 {
 332     sysbus_register_withprop(&milkymist_ac97_info);
 333 }
 334
 335 device_init(milkymist_ac97_register)