dusklight/libs/revolution/src/os/OSAudioSystem.c

#include <revolution.h>
#include <revolution/os.h>

#include <cstring>

#include "__os.h"

// prototypes
void __AIClockInit(u32);

static u8 DSPInitCode[128] = {
    0x02, 0x9F, 0x00, 0x10, 0x02, 0x9F, 0x00, 0x33, 0x02, 0x9F, 0x00, 0x34, 0x02, 0x9F, 0x00, 0x35,
    0x02, 0x9F, 0x00, 0x36, 0x02, 0x9F, 0x00, 0x37, 0x02, 0x9F, 0x00, 0x38, 0x02, 0x9F, 0x00, 0x39,
    0x12, 0x06, 0x12, 0x03, 0x12, 0x04, 0x12, 0x05, 0x00, 0x80, 0x80, 0x00, 0x00, 0x88, 0xFF, 0xFF,
    0x00, 0x84, 0x10, 0x00, 0x00, 0x64, 0x00, 0x1D, 0x02, 0x18, 0x00, 0x00, 0x81, 0x00, 0x1C, 0x1E,
    0x00, 0x44, 0x1B, 0x1E, 0x00, 0x84, 0x08, 0x00, 0x00, 0x64, 0x00, 0x27, 0x19, 0x1E, 0x00, 0x00,
    0x00, 0xDE, 0xFF, 0xFC, 0x02, 0xA0, 0x80, 0x00, 0x02, 0x9C, 0x00, 0x28, 0x16, 0xFC, 0x00, 0x54,
    0x16, 0xFD, 0x43, 0x48, 0x00, 0x21, 0x02, 0xFF, 0x02, 0xFF, 0x02, 0xFF, 0x02, 0xFF, 0x02, 0xFF,
    0x02, 0xFF, 0x02, 0xFF, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
};

static void waitMicroSec(u32 usec) {
    OSTick start_tick = OSGetTick();
    while (OSTicksToMicroseconds(OSGetTick() - start_tick) < usec);
}

#define PPCACR_OFFSET (OS_BASE_UNCACHED + 0x800000)
#define PPCACR (0xD000000 + PPCACR_OFFSET)

#define busRd32(addr) (*(volatile u32 *)(addr))
#define busWrt32(addr, val) (*(volatile u32 *)(addr)) = (val)

void __AIClockInit(u32 compatB) {
    u32 reg;

    reg = busRd32(PPCACR + 0x180);
    reg &= ~((u32)1 << 8);
    reg |= ((u32)compatB << 8);
    reg &= ~((u32)1 << 7);
    busWrt32(PPCACR + 0x180, reg);

    reg = busRd32(PPCACR + 0x1D0);
    reg &= ~((u32)1 << 31);
    reg &= ~((u32)1 << 30);
    busWrt32(PPCACR + 0x1D0, reg);

    waitMicroSec(100);

    if (compatB == 0) {
        reg = busRd32(PPCACR + 0x1CC);
        reg &= ~0x3FFC0;
        reg |= ((u32)63 << 6);
        reg &= ~0x3F;
        reg &= ~0x7FC0000;
        reg |= ((u32)281 << 18);
        busWrt32(PPCACR + 0x1CC, reg);
    } else {
        reg = busRd32(PPCACR + 0x1CC);
        reg &= ~0x3FFC0;
        reg |= ((u32)1023 << 6);
        reg &= ~0x3F;
        reg |= ((u32)14);
        reg &= ~0x7FC0000;
        reg |= ((u32)300 << 18);
        busWrt32(PPCACR + 0x1CC, reg);
    }

    waitMicroSec(100);

    reg = busRd32(PPCACR + 0x1D0);
    reg &= ~((u32)1 << 28);
    busWrt32(PPCACR + 0x1D0, reg);

    waitMicroSec(1000);

    reg = busRd32(PPCACR + 0x1D0);
    reg &= ~((u32)1 << 30);
    reg |= ((u32)1 << 30);
    busWrt32(PPCACR + 0x1D0, reg);

    waitMicroSec(1000);

    reg = busRd32(PPCACR + 0x1D0);
    reg &= ~((u32)1 << 31);
    reg |= ((u32)1 << 31);
    busWrt32(PPCACR + 0x1D0, reg);

    waitMicroSec(1000);
}

#define __DSPWorkBuffer (void*)0x81000000

void __OSInitAudioSystem(void) {
    u8 errFlag;
    u16 reg16;
    u32 start_tick;

    if (!__OSInIPL) {
        __AIClockInit(1);
    }

    memcpy((void*)((u32)OSGetArenaHi() - 0x80), __DSPWorkBuffer, sizeof(DSPInitCode));
    memcpy(__DSPWorkBuffer, (void*)DSPInitCode, sizeof(DSPInitCode));
    DCFlushRange(__DSPWorkBuffer, sizeof(DSPInitCode));

    __DSPRegs[9] = 0x43;
    ASSERTMSGLINE(253, !(__DSPRegs[5] & 0x200), "__OSInitAudioSystem(): ARAM DMA already in progress");
    ASSERTMSGLINE(257, !(__DSPRegs[5] & 0x400), "__OSInitAudioSystem(): DSP DMA already in progress");
    ASSERTMSGLINE(261, (__DSPRegs[5] & 0x004), "__OSInitAudioSystem(): DSP already working");
    
    __DSPRegs[5] = 0x8AC;
    __DSPRegs[5] |= 1;

    while (__DSPRegs[5] & 1);
        __DSPRegs[0] = 0;

    while (((__DSPRegs[2] << 16) | __DSPRegs[3]) & 0x80000000);

    *(u32*)&__DSPRegs[16] = 0x1000000;
    *(u32*)&__DSPRegs[18] = 0;
    *(u32*)&__DSPRegs[20] = 0x20;

    reg16 = __DSPRegs[5];
    while (!(reg16 & 0x20))
        reg16 = __DSPRegs[5];

    __DSPRegs[5] = reg16;

    start_tick = OSGetTick();
    while ((s32)(OSGetTick() - start_tick) < 0x892);

    *(u32*)&__DSPRegs[16] = 0x1000000;
    *(u32*)&__DSPRegs[18] = 0;
    *(u32*)&__DSPRegs[20] = 0x20;

    reg16 = __DSPRegs[5];
    while (!(reg16 & 0x20)) {
        reg16 = __DSPRegs[5];
    }
    __DSPRegs[5] = reg16;

    __DSPRegs[5] &= ~0x800;
    while ((__DSPRegs[5]) & 0x400);
    
    __DSPRegs[5] &= ~4;
    errFlag = 0;

    reg16 = __DSPRegs[2];

    while (!(reg16 & 0x8000)) {
        reg16 = __DSPRegs[2];
    }

    if(((u32)((reg16 << 16) | __DSPRegs[3]) + 0x7FAC0000U) != 0x4348) {
        ASSERTMSGLINE(333, 0, "__OSInitAudioSystem(): DSP returns invalid message");
    }

    __DSPRegs[5] |= 4;
    __DSPRegs[5] = 0x8AC;
    __DSPRegs[5] |= 1;
    while (__DSPRegs[5] & 1);

    memcpy(__DSPWorkBuffer, (void*)((u32)OSGetArenaHi() - 0x80), sizeof(DSPInitCode));
}

void __OSStopAudioSystem(void) {
    u16 reg16;
    u32 start_tick;

    #define waitUntil(load, mask)  \
        reg16 = (load);            \
        while (reg16 & (mask)) {   \
            reg16 = (load);        \
        }

    __DSPRegs[5] = 0x804;
    reg16 = __DSPRegs[27];
    __DSPRegs[27] = reg16 & ~0x8000;
    waitUntil(__DSPRegs[5], 0x400);
    waitUntil(__DSPRegs[5], 0x200);
    __DSPRegs[5] = 0x8ac;
    __DSPRegs[0] = 0;

    while (((__DSPRegs[2] << 16) | __DSPRegs[3]) & 0x80000000);

    start_tick = OSGetTick();
    while ((s32)(OSGetTick() - start_tick) < 0x2c);

    reg16 = __DSPRegs[5];
    __DSPRegs[5] = reg16 | 1;
    waitUntil(__DSPRegs[5], 0x001);

    #undef waitUntil
}