void dc_state::g2_dma_execute(address_space &space, int channel)
{
UINT32 src,dst,size;
dst = m_g2_dma[channel].g2_addr;
src = m_g2_dma[channel].root_addr;
size = 0;
/* 0 rounding size = 32 Mbytes */
if (m_g2_dma[channel].size == 0) { m_g2_dma[channel].size = 0x200000; }
if (m_g2_dma[channel].dir == 0)
{
for (; size<m_g2_dma[channel].size; size += 4)
{
space.write_dword(dst,space.read_dword(src));
src+=4;
dst+=4;
}
}
else
{
for (; size<m_g2_dma[channel].size; size += 4)
{
space.write_dword(src,space.read_dword(dst));
src+=4;
dst+=4;
}
}
/* update the params*/
m_g2_dma[channel].g2_addr = g2bus_regs[SB_ADSTAG + (channel * 8)] = dst;
m_g2_dma[channel].root_addr = g2bus_regs[SB_ADSTAR + (channel * 8)] = src;
m_g2_dma[channel].size = g2bus_regs[SB_ADLEN + (channel * 8)] = 0;
m_g2_dma[channel].flag = (m_g2_dma[channel].indirect & 1) ? 1 : 0;
/* Note: if you trigger an instant DMA IRQ trigger, sfz3upper doesn't play any bgm. */
/* TODO: timing of this */
machine().scheduler().timer_set(m_maincpu->cycles_to_attotime(m_g2_dma[channel].size / 4), timer_expired_delegate(FUNC(dc_state::g2_dma_irq), this), channel);
}
