melonDS/src/DMA.cpp
2023-11-04 00:21:46 +01:00

716 lines
19 KiB
C++

/*
Copyright 2016-2023 melonDS team
This file is part of melonDS.
melonDS is free software: you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation, either version 3 of the License, or (at your option)
any later version.
melonDS is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along
with melonDS. If not, see http://www.gnu.org/licenses/.
*/
#include <stdio.h>
#include "NDS.h"
#include "DSi.h"
#include "DMA.h"
#include "GPU.h"
#include "DMA_Timings.h"
#include "Platform.h"
using Platform::Log;
using Platform::LogLevel;
// DMA TIMINGS
//
// sequential timing:
// * 1 cycle per read or write
// * in 32bit mode, accessing a 16bit bus (mainRAM, palette, VRAM) incurs 1 cycle of penalty
// * in 32bit mode, transferring from mainRAM to another bank is 1 cycle faster
// * if source and destination are the same memory bank, there is a 1 cycle penalty
// * transferring from mainRAM to mainRAM is a trainwreck (all accesses are made nonsequential)
//
// nonsequential timing:
// * nonseq penalty is applied to the first read and write
// * I also figure it gets nonseq penalty again when resuming, after having been interrupted by
// another DMA (TODO: check)
// * applied to all accesses for mainRAM->mainRAM, resulting in timings of 16-18 cycles per unit
//
// TODO: GBA slot
// TODO: re-add initial NS delay
// TODO: timings are nonseq when address is fixed/decrementing
DMA::DMA(u32 cpu, u32 num) :
CPU(cpu),
Num(num)
{
if (cpu == 0)
CountMask = 0x001FFFFF;
else
CountMask = (num==3 ? 0x0000FFFF : 0x00003FFF);
}
void DMA::Reset()
{
SrcAddr = 0;
DstAddr = 0;
Cnt = 0;
StartMode = 0;
CurSrcAddr = 0;
CurDstAddr = 0;
RemCount = 0;
IterCount = 0;
SrcAddrInc = 0;
DstAddrInc = 0;
Stall = false;
Running = false;
Executing = false;
InProgress = false;
MRAMBurstCount = 0;
MRAMBurstTable = DMATiming::MRAMDummy;
}
void DMA::DoSavestate(Savestate* file)
{
char magic[5] = "DMAx";
magic[3] = '0' + Num + (CPU*4);
file->Section(magic);
file->Var32(&SrcAddr);
file->Var32(&DstAddr);
file->Var32(&Cnt);
file->Var32(&StartMode);
file->Var32(&CurSrcAddr);
file->Var32(&CurDstAddr);
file->Var32(&RemCount);
file->Var32(&IterCount);
file->Var32((u32*)&SrcAddrInc);
file->Var32((u32*)&DstAddrInc);
file->Var32(&Running);
file->Bool32(&InProgress);
file->Bool32(&IsGXFIFODMA);
file->Var32(&MRAMBurstCount);
file->Bool32(&Executing);
file->Bool32(&Stall);
file->VarArray(MRAMBurstTable.data(), sizeof(MRAMBurstTable));
}
void DMA::WriteCnt(u32 val)
{
u32 oldcnt = Cnt;
Cnt = val;
if ((!(oldcnt & 0x80000000)) && (val & 0x80000000))
{
CurSrcAddr = SrcAddr;
CurDstAddr = DstAddr;
switch (Cnt & 0x00600000)
{
case 0x00000000: DstAddrInc = 1; break;
case 0x00200000: DstAddrInc = -1; break;
case 0x00400000: DstAddrInc = 0; break;
case 0x00600000: DstAddrInc = 1; break;
}
switch (Cnt & 0x01800000)
{
case 0x00000000: SrcAddrInc = 1; break;
case 0x00800000: SrcAddrInc = -1; break;
case 0x01000000: SrcAddrInc = 0; break;
case 0x01800000: SrcAddrInc = 1; break;
}
if (CPU == 0)
StartMode = (Cnt >> 27) & 0x7;
else
StartMode = ((Cnt >> 28) & 0x3) | 0x10;
if ((StartMode & 0x7) == 0)
Start();
else if (StartMode == 0x07)
GPU3D::CheckFIFODMA();
if (StartMode==0x06 || StartMode==0x13)
Log(LogLevel::Warn, "UNIMPLEMENTED ARM%d DMA%d START MODE %02X, %08X->%08X\n", CPU?7:9, Num, StartMode, SrcAddr, DstAddr);
}
}
void DMA::Start()
{
if (Running) return;
if (!InProgress)
{
u32 countmask;
if (CPU == 0)
countmask = 0x001FFFFF;
else
countmask = (Num==3 ? 0x0000FFFF : 0x00003FFF);
RemCount = Cnt & countmask;
if (!RemCount)
RemCount = countmask+1;
}
if (StartMode == 0x07 && RemCount > 112)
IterCount = 112;
else
IterCount = RemCount;
if ((Cnt & 0x01800000) == 0x01800000)
CurSrcAddr = SrcAddr;
if ((Cnt & 0x00600000) == 0x00600000)
CurDstAddr = DstAddr;
//printf("ARM%d DMA%d %08X %02X %08X->%08X %d bytes %dbit\n", CPU?7:9, Num, Cnt, StartMode, CurSrcAddr, CurDstAddr, RemCount*((Cnt&0x04000000)?4:2), (Cnt&0x04000000)?32:16);
IsGXFIFODMA = (CPU == 0 && (CurSrcAddr>>24) == 0x02 && CurDstAddr == 0x04000400 && DstAddrInc == 0);
// TODO eventually: not stop if we're running code in ITCM
Running = 2;
// safety measure
MRAMBurstTable = DMATiming::MRAMDummy;
InProgress = true;
NDS::StopCPU(CPU, 1<<Num);
}
u32 DMA::UnitTimings9_16(bool burststart)
{
u32 src_id = CurSrcAddr >> 14;
u32 dst_id = CurDstAddr >> 14;
u32 src_rgn = NDS::ARM9Regions[src_id];
u32 dst_rgn = NDS::ARM9Regions[dst_id];
u32 src_n, src_s, dst_n, dst_s;
src_n = NDS::ARM9MemTimings[src_id][4];
src_s = NDS::ARM9MemTimings[src_id][5];
dst_n = NDS::ARM9MemTimings[dst_id][4];
dst_s = NDS::ARM9MemTimings[dst_id][5];
if (src_rgn == NDS::Mem9_MainRAM)
{
if (dst_rgn == NDS::Mem9_MainRAM)
return 16;
if (SrcAddrInc > 0)
{
if (burststart || MRAMBurstTable[MRAMBurstCount] == 0)
{
MRAMBurstCount = 0;
if (dst_rgn == NDS::Mem9_GBAROM)
{
if (dst_s == 4)
MRAMBurstTable = DMATiming::MRAMRead16Bursts[1];
else
MRAMBurstTable = DMATiming::MRAMRead16Bursts[2];
}
else
MRAMBurstTable = DMATiming::MRAMRead16Bursts[0];
}
u32 ret = MRAMBurstTable[MRAMBurstCount++];
return ret;
}
else
{
// TODO: not quite right for GBA slot
return (((CurSrcAddr & 0x1F) == 0x1E) ? 7 : 8) +
(burststart ? dst_n : dst_s);
}
}
else if (dst_rgn == NDS::Mem9_MainRAM)
{
if (DstAddrInc > 0)
{
if (burststart || MRAMBurstTable[MRAMBurstCount] == 0)
{
MRAMBurstCount = 0;
if (src_rgn == NDS::Mem9_GBAROM)
{
if (src_s == 4)
MRAMBurstTable = DMATiming::MRAMWrite16Bursts[1];
else
MRAMBurstTable = DMATiming::MRAMWrite16Bursts[2];
}
else
MRAMBurstTable = DMATiming::MRAMWrite16Bursts[0];
}
u32 ret = MRAMBurstTable[MRAMBurstCount++];
return ret;
}
else
{
return (burststart ? src_n : src_s) + 7;
}
}
else if (src_rgn & dst_rgn)
{
return src_n + dst_n + 1;
}
else
{
if (burststart)
return src_n + dst_n;
else
return src_s + dst_s;
}
}
u32 DMA::UnitTimings9_32(bool burststart)
{
u32 src_id = CurSrcAddr >> 14;
u32 dst_id = CurDstAddr >> 14;
u32 src_rgn = NDS::ARM9Regions[src_id];
u32 dst_rgn = NDS::ARM9Regions[dst_id];
u32 src_n, src_s, dst_n, dst_s;
src_n = NDS::ARM9MemTimings[src_id][6];
src_s = NDS::ARM9MemTimings[src_id][7];
dst_n = NDS::ARM9MemTimings[dst_id][6];
dst_s = NDS::ARM9MemTimings[dst_id][7];
if (src_rgn == NDS::Mem9_MainRAM)
{
if (dst_rgn == NDS::Mem9_MainRAM)
return 18;
if (SrcAddrInc > 0)
{
if (burststart || MRAMBurstTable[MRAMBurstCount] == 0)
{
MRAMBurstCount = 0;
if (dst_rgn == NDS::Mem9_GBAROM)
{
if (dst_s == 8)
MRAMBurstTable = DMATiming::MRAMRead32Bursts[2];
else
MRAMBurstTable = DMATiming::MRAMRead32Bursts[3];
}
else if (dst_n == 2)
MRAMBurstTable = DMATiming::MRAMRead32Bursts[0];
else
MRAMBurstTable = DMATiming::MRAMRead32Bursts[1];
}
u32 ret = MRAMBurstTable[MRAMBurstCount++];
return ret;
}
else
{
// TODO: not quite right for GBA slot
return (((CurSrcAddr & 0x1F) == 0x1C) ? (dst_n==2 ? 7:8) : 9) +
(burststart ? dst_n : dst_s);
}
}
else if (dst_rgn == NDS::Mem9_MainRAM)
{
if (DstAddrInc > 0)
{
if (burststart || MRAMBurstTable[MRAMBurstCount] == 0)
{
MRAMBurstCount = 0;
if (src_rgn == NDS::Mem9_GBAROM)
{
if (src_s == 8)
MRAMBurstTable = DMATiming::MRAMWrite32Bursts[2];
else
MRAMBurstTable = DMATiming::MRAMWrite32Bursts[3];
}
else if (src_n == 2)
MRAMBurstTable = DMATiming::MRAMWrite32Bursts[0];
else
MRAMBurstTable = DMATiming::MRAMWrite32Bursts[1];
}
u32 ret = MRAMBurstTable[MRAMBurstCount++];
return ret;
}
else
{
return (burststart ? src_n : src_s) + 8;
}
}
else if (src_rgn & dst_rgn)
{
return src_n + dst_n + 1;
}
else
{
if (burststart)
return src_n + dst_n;
else
return src_s + dst_s;
}
}
// TODO: the ARM7 ones don't take into account that the two wifi regions have different timings
u32 DMA::UnitTimings7_16(bool burststart)
{
u32 src_id = CurSrcAddr >> 15;
u32 dst_id = CurDstAddr >> 15;
u32 src_rgn = NDS::ARM7Regions[src_id];
u32 dst_rgn = NDS::ARM7Regions[dst_id];
u32 src_n, src_s, dst_n, dst_s;
src_n = NDS::ARM7MemTimings[src_id][0];
src_s = NDS::ARM7MemTimings[src_id][1];
dst_n = NDS::ARM7MemTimings[dst_id][0];
dst_s = NDS::ARM7MemTimings[dst_id][1];
if (src_rgn == NDS::Mem7_MainRAM)
{
if (dst_rgn == NDS::Mem7_MainRAM)
return 16;
if (SrcAddrInc > 0)
{
if (burststart || MRAMBurstTable[MRAMBurstCount] == 0)
{
MRAMBurstCount = 0;
if (dst_rgn == NDS::Mem7_GBAROM || dst_rgn == NDS::Mem7_Wifi0 || dst_rgn == NDS::Mem7_Wifi1)
{
if (dst_s == 4)
MRAMBurstTable = DMATiming::MRAMRead16Bursts[1];
else
MRAMBurstTable = DMATiming::MRAMRead16Bursts[2];
}
else
MRAMBurstTable = DMATiming::MRAMRead16Bursts[0];
}
u32 ret = MRAMBurstTable[MRAMBurstCount++];
return ret;
}
else
{
// TODO: not quite right for GBA slot
return (((CurSrcAddr & 0x1F) == 0x1E) ? 7 : 8) +
(burststart ? dst_n : dst_s);
}
}
else if (dst_rgn == NDS::Mem7_MainRAM)
{
if (DstAddrInc > 0)
{
if (burststart || MRAMBurstTable[MRAMBurstCount] == 0)
{
MRAMBurstCount = 0;
if (src_rgn == NDS::Mem7_GBAROM || src_rgn == NDS::Mem7_Wifi0 || src_rgn == NDS::Mem7_Wifi1)
{
if (src_s == 4)
MRAMBurstTable = DMATiming::MRAMWrite16Bursts[1];
else
MRAMBurstTable = DMATiming::MRAMWrite16Bursts[2];
}
else
MRAMBurstTable = DMATiming::MRAMWrite16Bursts[0];
}
u32 ret = MRAMBurstTable[MRAMBurstCount++];
return ret;
}
else
{
return (burststart ? src_n : src_s) + 7;
}
}
else if (src_rgn & dst_rgn)
{
return src_n + dst_n + 1;
}
else
{
if (burststart)
return src_n + dst_n;
else
return src_s + dst_s;
}
}
u32 DMA::UnitTimings7_32(bool burststart)
{
u32 src_id = CurSrcAddr >> 15;
u32 dst_id = CurDstAddr >> 15;
u32 src_rgn = NDS::ARM7Regions[src_id];
u32 dst_rgn = NDS::ARM7Regions[dst_id];
u32 src_n, src_s, dst_n, dst_s;
src_n = NDS::ARM7MemTimings[src_id][2];
src_s = NDS::ARM7MemTimings[src_id][3];
dst_n = NDS::ARM7MemTimings[dst_id][2];
dst_s = NDS::ARM7MemTimings[dst_id][3];
if (src_rgn == NDS::Mem7_MainRAM)
{
if (dst_rgn == NDS::Mem7_MainRAM)
return 18;
if (SrcAddrInc > 0)
{
if (burststart || MRAMBurstTable[MRAMBurstCount] == 0)
{
MRAMBurstCount = 0;
if (dst_rgn == NDS::Mem7_GBAROM || dst_rgn == NDS::Mem7_Wifi0 || dst_rgn == NDS::Mem7_Wifi1)
{
if (dst_s == 8)
MRAMBurstTable = DMATiming::MRAMRead32Bursts[2];
else
MRAMBurstTable = DMATiming::MRAMRead32Bursts[3];
}
else if (dst_n == 2)
MRAMBurstTable = DMATiming::MRAMRead32Bursts[0];
else
MRAMBurstTable = DMATiming::MRAMRead32Bursts[1];
}
u32 ret = MRAMBurstTable[MRAMBurstCount++];
return ret;
}
else
{
// TODO: not quite right for GBA slot
return (((CurSrcAddr & 0x1F) == 0x1C) ? (dst_n==2 ? 7:8) : 9) +
(burststart ? dst_n : dst_s);
}
}
else if (dst_rgn == NDS::Mem7_MainRAM)
{
if (DstAddrInc > 0)
{
if (burststart || MRAMBurstTable[MRAMBurstCount] == 0)
{
MRAMBurstCount = 0;
if (src_rgn == NDS::Mem7_GBAROM || src_rgn == NDS::Mem7_Wifi0 || src_rgn == NDS::Mem7_Wifi1)
{
if (src_s == 8)
MRAMBurstTable = DMATiming::MRAMWrite32Bursts[2];
else
MRAMBurstTable = DMATiming::MRAMWrite32Bursts[3];
}
else if (src_n == 2)
MRAMBurstTable = DMATiming::MRAMWrite32Bursts[0];
else
MRAMBurstTable = DMATiming::MRAMWrite32Bursts[1];
}
u32 ret = MRAMBurstTable[MRAMBurstCount++];
return ret;
}
else
{
return (burststart ? src_n : src_s) + 8;
}
}
else if (src_rgn & dst_rgn)
{
return src_n + dst_n + 1;
}
else
{
if (burststart)
return src_n + dst_n;
else
return src_s + dst_s;
}
}
template <int ConsoleType>
void DMA::Run9()
{
if (NDS::ARM9Timestamp >= NDS::ARM9Target) return;
Executing = true;
// add NS penalty for first accesses in burst
bool burststart = (Running == 2);
Running = 1;
if (!(Cnt & (1<<26)))
{
while (IterCount > 0 && !Stall)
{
NDS::ARM9Timestamp += (UnitTimings9_16(burststart) << NDS::ARM9ClockShift);
burststart = false;
if (ConsoleType == 1)
DSi::ARM9Write16(CurDstAddr, DSi::ARM9Read16(CurSrcAddr));
else
NDS::ARM9Write16(CurDstAddr, NDS::ARM9Read16(CurSrcAddr));
CurSrcAddr += SrcAddrInc<<1;
CurDstAddr += DstAddrInc<<1;
IterCount--;
RemCount--;
if (NDS::ARM9Timestamp >= NDS::ARM9Target) break;
}
}
else
{
while (IterCount > 0 && !Stall)
{
NDS::ARM9Timestamp += (UnitTimings9_32(burststart) << NDS::ARM9ClockShift);
burststart = false;
if (ConsoleType == 1)
DSi::ARM9Write32(CurDstAddr, DSi::ARM9Read32(CurSrcAddr));
else
NDS::ARM9Write32(CurDstAddr, NDS::ARM9Read32(CurSrcAddr));
CurSrcAddr += SrcAddrInc<<2;
CurDstAddr += DstAddrInc<<2;
IterCount--;
RemCount--;
if (NDS::ARM9Timestamp >= NDS::ARM9Target) break;
}
}
Executing = false;
Stall = false;
if (RemCount)
{
if (IterCount == 0)
{
Running = 0;
NDS::ResumeCPU(0, 1<<Num);
if (StartMode == 0x07)
GPU3D::CheckFIFODMA();
}
return;
}
if (!(Cnt & (1<<25)))
Cnt &= ~(1<<31);
if (Cnt & (1<<30))
NDS::SetIRQ(0, NDS::IRQ_DMA0 + Num);
Running = 0;
InProgress = false;
NDS::ResumeCPU(0, 1<<Num);
}
template <int ConsoleType>
void DMA::Run7()
{
if (NDS::ARM7Timestamp >= NDS::ARM7Target) return;
Executing = true;
// add NS penalty for first accesses in burst
bool burststart = (Running == 2);
Running = 1;
if (!(Cnt & (1<<26)))
{
while (IterCount > 0 && !Stall)
{
NDS::ARM7Timestamp += UnitTimings7_16(burststart);
burststart = false;
if (ConsoleType == 1)
DSi::ARM7Write16(CurDstAddr, DSi::ARM7Read16(CurSrcAddr));
else
NDS::ARM7Write16(CurDstAddr, NDS::ARM7Read16(CurSrcAddr));
CurSrcAddr += SrcAddrInc<<1;
CurDstAddr += DstAddrInc<<1;
IterCount--;
RemCount--;
if (NDS::ARM7Timestamp >= NDS::ARM7Target) break;
}
}
else
{
while (IterCount > 0 && !Stall)
{
NDS::ARM7Timestamp += UnitTimings7_32(burststart);
burststart = false;
if (ConsoleType == 1)
DSi::ARM7Write32(CurDstAddr, DSi::ARM7Read32(CurSrcAddr));
else
NDS::ARM7Write32(CurDstAddr, NDS::ARM7Read32(CurSrcAddr));
CurSrcAddr += SrcAddrInc<<2;
CurDstAddr += DstAddrInc<<2;
IterCount--;
RemCount--;
if (NDS::ARM7Timestamp >= NDS::ARM7Target) break;
}
}
Executing = false;
Stall = false;
if (RemCount)
{
if (IterCount == 0)
{
Running = 0;
NDS::ResumeCPU(1, 1<<Num);
}
return;
}
if (!(Cnt & (1<<25)))
Cnt &= ~(1<<31);
if (Cnt & (1<<30))
NDS::SetIRQ(1, NDS::IRQ_DMA0 + Num);
Running = 0;
InProgress = false;
NDS::ResumeCPU(1, 1<<Num);
}
template <int ConsoleType>
void DMA::Run()
{
if (!Running) return;
if (CPU == 0) return Run9<ConsoleType>();
else return Run7<ConsoleType>();
}
template void DMA::Run<0>();
template void DMA::Run<1>();