sb16.c

qemu虚拟机代码

        case 0x47:                /* Continue Auto-Initialize DMA 16bit */
            break;

        case 0x48:
            s->needed_bytes = 2;
            break;

        case 0x74:
            s->needed_bytes = 2; /* DMA DAC, 4-bit ADPCM */
            dolog ("0x75 - DMA DAC, 4-bit ADPCM not implemented\n");
            break;

        case 0x75:              /* DMA DAC, 4-bit ADPCM Reference */
            s->needed_bytes = 2;
            dolog ("0x74 - DMA DAC, 4-bit ADPCM Reference not implemented\n");
            break;

        case 0x76:              /* DMA DAC, 2.6-bit ADPCM */
            s->needed_bytes = 2;
            dolog ("0x74 - DMA DAC, 2.6-bit ADPCM not implemented\n");
            break;

        case 0x77:              /* DMA DAC, 2.6-bit ADPCM Reference */
            s->needed_bytes = 2;
            dolog ("0x74 - DMA DAC, 2.6-bit ADPCM Reference not implemented\n");
            break;

        case 0x7d:
            dolog ("0x7d - Autio-Initialize DMA DAC, 4-bit ADPCM Reference\n");
            dolog ("not implemented\n");
            break;

        case 0x7f:
            dolog (
                "0x7d - Autio-Initialize DMA DAC, 2.6-bit ADPCM Reference\n"
                );
            dolog ("not implemented\n");
            break;

        case 0x80:
            s->needed_bytes = 2;
            break;

        case 0x90:
        case 0x91:
            dma_cmd8 (s, ((cmd & 1) == 0) | DMA8_HIGH, -1);
            break;

        case 0xd0:              /* halt DMA operation. 8bit */
            control (s, 0);
            break;

        case 0xd1:              /* speaker on */
            speaker (s, 1);
            break;

        case 0xd3:              /* speaker off */
            speaker (s, 0);
            break;

        case 0xd4:              /* continue DMA operation. 8bit */
            control (s, 1);
            break;

        case 0xd5:              /* halt DMA operation. 16bit */
            control (s, 0);
            break;

        case 0xd6:              /* continue DMA operation. 16bit */
            control (s, 1);
            break;

        case 0xd9:              /* exit auto-init DMA after this block. 16bit */
            s->dma_auto = 0;
            break;

        case 0xda:              /* exit auto-init DMA after this block. 8bit */
            s->dma_auto = 0;
            break;

        case 0xe0:              /* DSP identification */
            s->needed_bytes = 1;
            break;

        case 0xe1:
            dsp_out_data (s, s->ver & 0xff);
            dsp_out_data (s, s->ver >> 8);
            break;

        case 0xe2:
            s->needed_bytes = 1;
            goto warn;

        case 0xe3:
            {
                int i;
                for (i = sizeof (e3) - 1; i >= 0; --i)
                    dsp_out_data (s, e3[i]);
            }
            break;

        case 0xe4:              /* write test reg */
            s->needed_bytes = 1;
            break;

        case 0xe7:
            dolog ("Attempt to probe for ESS (0xe7)?\n");
            break;

        case 0xe8:              /* read test reg */
            dsp_out_data (s, s->test_reg);
            break;

        case 0xf2:
        case 0xf3:
            dsp_out_data (s, 0xaa);
            s->mixer_regs[0x82] |= (cmd == 0xf2) ? 1 : 2;
            pic_set_irq (s->irq, 1);
            break;

        case 0xf9:
            s->needed_bytes = 1;
            goto warn;

        case 0xfa:
            dsp_out_data (s, 0);
            goto warn;

        case 0xfc:              /* FIXME */
            dsp_out_data (s, 0);
            goto warn;

        default:
            dolog ("Unrecognized command %#x\n", cmd);
            break;
        }
    }

    if (!s->needed_bytes) {
        ldebug ("\n");
    }

 exit:
    if (!s->needed_bytes) {
        s->cmd = -1;
    }
    else {
        s->cmd = cmd;
    }
    return;

 warn:
    dolog ("warning: command %#x,%d is not truly understood yet\n",
           cmd, s->needed_bytes);
    goto exit;

}

static uint16_t dsp_get_lohi (SB16State *s)
{
    uint8_t hi = dsp_get_data (s);
    uint8_t lo = dsp_get_data (s);
    return (hi << 8) | lo;
}

static uint16_t dsp_get_hilo (SB16State *s)
{
    uint8_t lo = dsp_get_data (s);
    uint8_t hi = dsp_get_data (s);
    return (hi << 8) | lo;
}

static void complete (SB16State *s)
{
    int d0, d1, d2;
    ldebug ("complete command %#x, in_index %d, needed_bytes %d\n",
            s->cmd, s->in_index, s->needed_bytes);

    if (s->cmd > 0xaf && s->cmd < 0xd0) {
        d2 = dsp_get_data (s);
        d1 = dsp_get_data (s);
        d0 = dsp_get_data (s);

        if (s->cmd & 8) {
            dolog ("ADC params cmd = %#x d0 = %d, d1 = %d, d2 = %d\n",
                   s->cmd, d0, d1, d2);
        }
        else {
            ldebug ("cmd = %#x d0 = %d, d1 = %d, d2 = %d\n",
                    s->cmd, d0, d1, d2);
            dma_cmd (s, s->cmd, d0, d1 + (d2 << 8));
        }
    }
    else {
        switch (s->cmd) {
        case 0x04:
            s->csp_mode = dsp_get_data (s);
            s->csp_reg83r = 0;
            s->csp_reg83w = 0;
            ldebug ("CSP command 0x04: mode=%#x\n", s->csp_mode);
            break;

        case 0x05:
            s->csp_param = dsp_get_data (s);
            s->csp_value = dsp_get_data (s);
            ldebug ("CSP command 0x05: param=%#x value=%#x\n",
                    s->csp_param,
                    s->csp_value);
            break;

        case 0x0e:
            d0 = dsp_get_data (s);
            d1 = dsp_get_data (s);
            ldebug ("write CSP register %d <- %#x\n", d1, d0);
            if (d1 == 0x83) {
                ldebug ("0x83[%d] <- %#x\n", s->csp_reg83r, d0);
                s->csp_reg83[s->csp_reg83r % 4] = d0;
                s->csp_reg83r += 1;
            }
            else {
                s->csp_regs[d1] = d0;
            }
            break;

        case 0x0f:
            d0 = dsp_get_data (s);
            ldebug ("read CSP register %#x -> %#x, mode=%#x\n",
                    d0, s->csp_regs[d0], s->csp_mode);
            if (d0 == 0x83) {
                ldebug ("0x83[%d] -> %#x\n",
                        s->csp_reg83w,
                        s->csp_reg83[s->csp_reg83w % 4]);
                dsp_out_data (s, s->csp_reg83[s->csp_reg83w % 4]);
                s->csp_reg83w += 1;
            }
            else {
                dsp_out_data (s, s->csp_regs[d0]);
            }
            break;

        case 0x10:
            d0 = dsp_get_data (s);
            dolog ("cmd 0x10 d0=%#x\n", d0);
            break;

        case 0x14:
            dma_cmd8 (s, 0, dsp_get_lohi (s) + 1);
            break;

        case 0x40:
            s->time_const = dsp_get_data (s);
            ldebug ("set time const %d\n", s->time_const);
            break;

        case 0x42:              /* FT2 sets output freq with this, go figure */
#if 0
            dolog ("cmd 0x42 might not do what it think it should\n");
#endif
        case 0x41:
            s->freq = dsp_get_hilo (s);
            ldebug ("set freq %d\n", s->freq);
            break;

        case 0x48:
            s->block_size = dsp_get_lohi (s) + 1;
            ldebug ("set dma block len %d\n", s->block_size);
            break;

        case 0x74:
        case 0x75:
        case 0x76:
        case 0x77:
            /* ADPCM stuff, ignore */
            break;

        case 0x80:
            {
                int freq, samples, bytes;
                int64_t ticks;

                freq = s->freq > 0 ? s->freq : 11025;
                samples = dsp_get_lohi (s) + 1;
                bytes = samples << s->fmt_stereo << (s->fmt_bits == 16);
                ticks = (bytes * ticks_per_sec) / freq;
                if (ticks < ticks_per_sec / 1024) {
                    pic_set_irq (s->irq, 1);
                }
                else {
                    if (s->aux_ts) {
                        qemu_mod_timer (
                            s->aux_ts,
                            qemu_get_clock (vm_clock) + ticks
                            );
                    }
                }
                ldebug ("mix silence %d %d %lld\n", samples, bytes, ticks);
            }
            break;

        case 0xe0:
            d0 = dsp_get_data (s);
            s->out_data_len = 0;
            ldebug ("E0 data = %#x\n", d0);
            dsp_out_data (s, ~d0);
            break;

        case 0xe2:
            d0 = dsp_get_data (s);
            ldebug ("E2 = %#x\n", d0);
            break;

        case 0xe4:
            s->test_reg = dsp_get_data (s);
            break;

        case 0xf9:
            d0 = dsp_get_data (s);
            ldebug ("command 0xf9 with %#x\n", d0);
            switch (d0) {
            case 0x0e:
                dsp_out_data (s, 0xff);
                break;

            case 0x0f:
                dsp_out_data (s, 0x07);
                break;

            case 0x37:
                dsp_out_data (s, 0x38);
                break;

            default:
                dsp_out_data (s, 0x00);
                break;
            }
            break;

        default:
            dolog ("complete: unrecognized command %#x\n", s->cmd);
            return;
        }
    }

    ldebug ("\n");
    s->cmd = -1;
    return;
}

static void reset (SB16State *s)
{
    pic_set_irq (s->irq, 0);
    if (s->dma_auto) {
        pic_set_irq (s->irq, 1);
        pic_set_irq (s->irq, 0);
    }

    s->mixer_regs[0x82] = 0;
    s->dma_auto = 0;
    s->in_index = 0;
    s->out_data_len = 0;
    s->left_till_irq = 0;
    s->needed_bytes = 0;
    s->block_size = -1;
    s->nzero = 0;
    s->highspeed = 0;
    s->v2x6 = 0;
    s->cmd = -1;

    dsp_out_data(s, 0xaa);
    speaker (s, 0);
    control (s, 0);
}

static IO_WRITE_PROTO (dsp_write)
{
    SB16State *s = opaque;
    int iport;

    iport = nport - s->port;

    ldebug ("write %#x <- %#x\n", nport, val);
    switch (iport) {
    case 0x06:
        switch (val) {
        case 0x00:
            if (s->v2x6 == 1) {
                if (0 && s->highspeed) {
                    s->highspeed = 0;
                    pic_set_irq (s->irq, 0);
                    control (s, 0);
                }
                else {
                    reset (s);
                }
            }
            s->v2x6 = 0;
            break;

        case 0x01:
        case 0x03:              /* FreeBSD kludge */
            s->v2x6 = 1;
            break;

        case 0xc6:
            s->v2x6 = 0;        /* Prince of Persia, csp.sys, diagnose.exe */
            break;

        case 0xb8:              /* Panic */
            reset (s);
            break;

        case 0x39:
            dsp_out_data (s, 0x38);
            reset (s);
            s->v2x6 = 0x39;
            break;

        default:
            s->v2x6 = val;
            break;
        }
        break;

    case 0x0c:                  /* write data or command | write status */
/*         if (s->highspeed) */
/*             break; */

        if (0 == s->needed_bytes) {
            command (s, val);
#if 0
            if (0 == s->needed_bytes) {
                log_dsp (s);
            }
#endif
        }
        else {
            if (s->in_index == sizeof (s->in2_data)) {
                dolog ("in data overrun\n");
            }
            else {
                s->in2_data[s->in_index++] = val;
                if (s->in_index == s->needed_bytes) {
                    s->needed_bytes = 0;
                    complete (s);
#if 0
                    log_dsp (s);
#endif
                }
            }
        }
        break;

    default:
        ldebug ("(nport=%#x, val=%#x)\n", nport, val);
        break;
    }
}

static IO_READ_PROTO (dsp_read)
{
    SB16State *s = opaque;
    int iport, retval, ack = 0;

    iport = nport - s->port;

    switch (iport) {
    case 0x06:                  /* reset */
        retval = 0xff;
        break;

    case 0x0a:                  /* read data */
        if (s->out_data_len) {