Function __SITransfer

src/dolphin/src/si/SIBios.c:359–402

#define ROUND(n, a) (((u32)(n) + (a)-1) & ~((a)-1))

static BOOL __SITransfer(s32 chan, void* output, u32 outputBytes, void* input, u32 inputBytes,
                         SICallback callback)
{
    BOOL enabled;
    u32 rLen;
    u32 i;
    u32 sr;
    SIComm_u comcsr;

    enabled = OSDisableInterrupts();
    if (Si.chan != -1)
    {
        OSRestoreInterrupts(enabled);
        return FALSE;
    }

    sr = __SIRegs[14];
    sr &= (0xf000000) >> (8 * chan);
    __SIRegs[14] = sr;

    Si.chan = chan;
    Si.callback = callback;
    Si.inputBytes = inputBytes;
    Si.input = input;

    rLen = ROUND(outputBytes, 4) / 4;
    for (i = 0; i < rLen; i++)
    {
        __SIRegs[32 + i] = ((u32*)output)[i];
    }

    comcsr.val = __SIRegs[13];
    comcsr.f.tcint = 1;
    comcsr.f.tcintmsk = callback ? 1 : 0;
    comcsr.f.outlngth = (outputBytes == SI_MAX_COMCSR_OUTLNGTH) ? 0 : outputBytes;
    comcsr.f.inlngth = (inputBytes == SI_MAX_COMCSR_INLNGTH) ? 0 : inputBytes;
    comcsr.f.channel = chan;
    comcsr.f.tstart = 1;
    __SIRegs[13] = comcsr.val;

    OSRestoreInterrupts(enabled);

    return TRUE;
}

u32 SIGetStatus(s32 chan)
{