flycast/core/hw/pvr/pvr_sb_regs.cpp

/*
	PVR-SB handling
	DMA hacks are here
*/

#include "pvr_sb_regs.h"
#include "ta.h"
#include "hw/holly/holly_intc.h"
#include "hw/holly/sb.h"
#include "hw/sh4/modules/dmac.h"
#include "hw/sh4/sh4_mem.h"

static void RegWrite_SB_C2DST(u32 addr, u32 data)
{
	if (data & 1)
	{
		SB_C2DST = 1;
		DMAC_Ch2St();
	}
}

//PVR-DMA
static void do_pvr_dma()
{
	u32 src = SB_PDSTAR;	// System RAM address
	u32 dst = SB_PDSTAP;	// VRAM address
	u32 len = SB_PDLEN;

	if (0x8201 != (DMAC_DMAOR.full & DMAOR_MASK))
	{
		INFO_LOG(PVR, "DMAC: DMAOR has invalid settings (%X) !", DMAC_DMAOR.full);
		return;
	}
	DEBUG_LOG(PVR, "PVR-DMA %x %s %x len %x", src, SB_PDDIR ? "<-" : "->", dst, len);

	if (SB_PDDIR)
		//PVR -> System
		WriteMemBlock_nommu_dma(src, dst, len);
	else
		//System -> PVR
		WriteMemBlock_nommu_dma(dst,src,len);

	DMAC_SAR(0) = src + len;
	DMAC_CHCR(0).TE = 1;
	DMAC_DMATCR(0) = 0;

	SB_PDST = 0;

	asic_RaiseInterrupt(holly_PVR_DMA);
}

static void RegWrite_SB_PDST(u32 addr, u32 data)
{
	if (data & 1)
	{
		SB_PDST = 1;
		do_pvr_dma();
	}
}

// Auto sort DMA
static u32 calculate_start_link_addr()
{
	u8* base = &mem_b[SB_SDSTAW & RAM_MASK];
	u32 rv;
	if (SB_SDWLT == 0)
		//16b width
		rv = ((u16*)base)[SB_SDDIV];
	else
		//32b width
		rv = ((u32*)base)[SB_SDDIV];
	SB_SDDIV++; //next index

	return rv;
}

static void pvr_do_sort_dma()
{
	DEBUG_LOG(PVR, "Sort-DMA SB_SDSTAW %x SB_SDDIV %x SB_SDBAAW %x", SB_SDSTAW, SB_SDDIV, SB_SDBAAW);
	SB_SDDIV = 0; // index is 0 now
	u32 link_addr = calculate_start_link_addr();

	while (link_addr != 2)
	{
		if (SB_SDLAS == 1)
			link_addr *= 32;
		else
			link_addr &= ~31;

		u32 ea = (SB_SDBAAW + link_addr) & RAM_MASK;
		u32* ea_ptr = (u32 *)&mem_b[ea];

		link_addr = ea_ptr[0x1C >> 2];//Next link
		//transfer global param
		ta_vtx_data((const SQBuffer *)ea_ptr, ea_ptr[0x18 >> 2]);
		if (link_addr == 1)
			link_addr = calculate_start_link_addr();
	}

	// End of DMA
	SB_SDST = 0;
	SB_SDSTAW += 32;
	asic_RaiseInterrupt(holly_PVR_SortDMA);
}

static void RegWrite_SB_SDST(u32 addr, u32 data)
{
	if (data & 1)
		pvr_do_sort_dma();
}

void pvr_sb_Init()
{
	//0x005F7C18    SB_PDST RW  PVR-DMA start
	sb_rio_register(SB_PDST_addr,RIO_WF,0,&RegWrite_SB_PDST);

	//0x005F6808    SB_C2DST RW  ch2-DMA start 
	sb_rio_register(SB_C2DST_addr,RIO_WF,0,&RegWrite_SB_C2DST);

	//0x005F6820    SB_SDST RW  Sort-DMA start
	sb_rio_register(SB_SDST_addr,RIO_WF,0,&RegWrite_SB_SDST);
}

void pvr_sb_Term()
{
}

void pvr_sb_Reset(bool hard)
{
}