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getting somewhere

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This commit is contained in:
Arisotura
2021-06-30 14:37:37 +02:00
parent d2bff7c187
commit 778d5468ec
1 changed files with 82 additions and 97 deletions
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179
src/DMA.cpp
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@ -270,8 +270,6 @@ u32 DMA::UnitTimings9_16(bool burststart)
dst_n = NDS::ARM9MemTimings[dst_id][4]; dst_n = NDS::ARM9MemTimings[dst_id][4];
dst_s = NDS::ARM9MemTimings[dst_id][5]; dst_s = NDS::ARM9MemTimings[dst_id][5];
u32 ret = 0;
if (src_rgn == NDS::Mem9_MainRAM) if (src_rgn == NDS::Mem9_MainRAM)
{ {
if (dst_rgn == NDS::Mem9_MainRAM) if (dst_rgn == NDS::Mem9_MainRAM)
@ -294,14 +292,13 @@ u32 DMA::UnitTimings9_16(bool burststart)
MRAMBurstTable = DMATiming::MRAMRead16Bursts[0]; MRAMBurstTable = DMATiming::MRAMRead16Bursts[0];
} }
ret = MRAMBurstTable[MRAMBurstCount++]; u32 ret = MRAMBurstTable[MRAMBurstCount++];
return ret; return ret;
} }
else else
{ {
ret += ((CurSrcAddr & 0x1F) == 0x1E) ? 7 : 8; return (((CurSrcAddr & 0x1F) == 0x1E) ? 7 : 8) +
ret += burststart ? dst_n : dst_s; (burststart ? dst_n : dst_s);
return ret;
} }
} }
else if (dst_rgn == NDS::Mem9_MainRAM) else if (dst_rgn == NDS::Mem9_MainRAM)
@ -323,14 +320,12 @@ u32 DMA::UnitTimings9_16(bool burststart)
MRAMBurstTable = DMATiming::MRAMWrite16Bursts[0]; MRAMBurstTable = DMATiming::MRAMWrite16Bursts[0];
} }
ret = MRAMBurstTable[MRAMBurstCount++]; u32 ret = MRAMBurstTable[MRAMBurstCount++];
return ret; return ret;
} }
else else
{ {
ret += burststart ? src_n : src_s; return (burststart ? src_n : src_s) + 7;
ret += 7;
return ret;
} }
} }
else if (src_rgn & dst_rgn) else if (src_rgn & dst_rgn)
@ -344,91 +339,6 @@ u32 DMA::UnitTimings9_16(bool burststart)
else else
return src_s + dst_s; return src_s + dst_s;
} }
#if 0
if (src_rgn == NDS::Mem9_MainRAM)
{
// for main RAM: sequential timings only work with incrementing addresses
// read bursts have a maximum length of 119 halfwords, then 119 halfwords, then 2 halfwords, and so on
// (this is probably a hardware glitch)
if (SrcAddrInc > 0)
{
if (burststart || BurstCount >= 240)
BurstCount = 0;
// note: one of the cycles of the first unit seems to transfer over to the next unit
// we approximate this by attributing all the cycles to the first unit
if (BurstCount == 0 || BurstCount == 119 || BurstCount == 238)
ret += src_n-1;
//else if (BurstCount == 1 || BurstCount == 120 || BurstCount == 239)
// ret += src_s + 1;
else
ret += src_s;
BurstCount++;
}
else
{
ret += src_n;
if ((CurSrcAddr & 0x1F) == 0x1E) ret--;
}
// main RAM reads can parallelize with writes to another region
//ret--;
}
else if (src_rgn == NDS::Mem9_GBAROM)
{
// for GBA ROM: sequential timings always work, except for the last halfword
// of every 0x20000 byte block
ret += (burststart || ((CurSrcAddr & 0x1FFFF) == 0x1FFFE)) ? src_n : src_s;
}
else
{
// for other regions: nonseq/sequential timings are the same
ret += src_s;
}
if (dst_rgn == NDS::Mem9_MainRAM)
{
// for main RAM: sequential timings only work with incrementing addresses
// write bursts have a maximum length of 120 halfwords
if (DstAddrInc > 0)
{
if (burststart || BurstCount >= 120)
BurstCount = 0;
ret += (BurstCount == 0) ? dst_n-1 : dst_s;
BurstCount++;
}
else
{
ret += dst_n-1;
}
}
else if (dst_rgn == NDS::Mem9_GBAROM)
{
// for GBA ROM: sequential timings always work, except for the last halfword
// of every 0x20000 byte block
ret += (burststart || ((CurDstAddr & 0x1FFFF) == 0x1FFFE)) ? dst_n : dst_s;
}
else
{
// for other regions: nonseq/sequential timings are the same
ret += dst_s;
}
#endif
return ret;
} }
u32 DMA::UnitTimings9_32(bool burststart) u32 DMA::UnitTimings9_32(bool burststart)
@ -445,6 +355,81 @@ u32 DMA::UnitTimings9_32(bool burststart)
dst_n = NDS::ARM9MemTimings[dst_id][6]; dst_n = NDS::ARM9MemTimings[dst_id][6];
dst_s = NDS::ARM9MemTimings[dst_id][7]; 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
{
return (((CurSrcAddr & 0x1F) == 0x1C) ? 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;
}
#if 0
if (src_rgn & dst_rgn) if (src_rgn & dst_rgn)
{ {
return src_n + dst_n; return src_n + dst_n;
@ -452,7 +437,7 @@ u32 DMA::UnitTimings9_32(bool burststart)
u32 ret = 0; u32 ret = 0;
ret=1; ret=1;
#if 0
if (src_rgn == NDS::Mem9_MainRAM) if (src_rgn == NDS::Mem9_MainRAM)
{ {
// for main RAM: sequential timings only work with incrementing addresses // for main RAM: sequential timings only work with incrementing addresses
@ -523,7 +508,7 @@ u32 DMA::UnitTimings9_32(bool burststart)
ret += dst_s; ret += dst_s;
} }
#endif #endif
return ret; // return ret;
} }
template <int ConsoleType> template <int ConsoleType>