ryujinx/Ryujinx.Graphics.Gpu/Memory/MemoryManager.cs
2020-01-09 02:13:00 +01:00

265 lines
7.1 KiB
C#

namespace Ryujinx.Graphics.Gpu.Memory
{
public class MemoryManager
{
private const ulong AddressSpaceSize = 1UL << 40;
public const ulong BadAddress = ulong.MaxValue;
private const int PtLvl0Bits = 14;
private const int PtLvl1Bits = 14;
private const int PtPageBits = 12;
private const ulong PtLvl0Size = 1UL << PtLvl0Bits;
private const ulong PtLvl1Size = 1UL << PtLvl1Bits;
public const ulong PageSize = 1UL << PtPageBits;
private const ulong PtLvl0Mask = PtLvl0Size - 1;
private const ulong PtLvl1Mask = PtLvl1Size - 1;
public const ulong PageMask = PageSize - 1;
private const int PtLvl0Bit = PtPageBits + PtLvl1Bits;
private const int PtLvl1Bit = PtPageBits;
private const ulong PteUnmapped = 0xffffffff_ffffffff;
private const ulong PteReserved = 0xffffffff_fffffffe;
private ulong[][] _pageTable;
public MemoryManager()
{
_pageTable = new ulong[PtLvl0Size][];
}
public ulong Map(ulong pa, ulong va, ulong size)
{
lock (_pageTable)
{
for (ulong offset = 0; offset < size; offset += PageSize)
{
SetPte(va + offset, pa + offset);
}
}
return va;
}
public ulong Map(ulong pa, ulong size)
{
lock (_pageTable)
{
ulong va = GetFreePosition(size);
if (va != PteUnmapped)
{
for (ulong offset = 0; offset < size; offset += PageSize)
{
SetPte(va + offset, pa + offset);
}
}
return va;
}
}
public ulong MapLow(ulong pa, ulong size)
{
lock (_pageTable)
{
ulong va = GetFreePosition(size, 1, PageSize);
if (va != PteUnmapped && va <= uint.MaxValue && (va + size) <= uint.MaxValue)
{
for (ulong offset = 0; offset < size; offset += PageSize)
{
SetPte(va + offset, pa + offset);
}
}
else
{
va = PteUnmapped;
}
return va;
}
}
public ulong ReserveFixed(ulong va, ulong size)
{
lock (_pageTable)
{
for (ulong offset = 0; offset < size; offset += PageSize)
{
if (IsPageInUse(va + offset))
{
return PteUnmapped;
}
}
for (ulong offset = 0; offset < size; offset += PageSize)
{
SetPte(va + offset, PteReserved);
}
}
return va;
}
public ulong Reserve(ulong size, ulong alignment)
{
lock (_pageTable)
{
ulong address = GetFreePosition(size, alignment);
if (address != PteUnmapped)
{
for (ulong offset = 0; offset < size; offset += PageSize)
{
SetPte(address + offset, PteReserved);
}
}
return address;
}
}
public void Free(ulong va, ulong size)
{
lock (_pageTable)
{
for (ulong offset = 0; offset < size; offset += PageSize)
{
SetPte(va + offset, PteUnmapped);
}
}
}
private ulong GetFreePosition(ulong size, ulong alignment = 1, ulong start = 1UL << 32)
{
// Note: Address 0 is not considered valid by the driver,
// when 0 is returned it's considered a mapping error.
ulong address = start;
ulong freeSize = 0;
if (alignment == 0)
{
alignment = 1;
}
alignment = (alignment + PageMask) & ~PageMask;
while (address + freeSize < AddressSpaceSize)
{
if (!IsPageInUse(address + freeSize))
{
freeSize += PageSize;
if (freeSize >= size)
{
return address;
}
}
else
{
address += freeSize + PageSize;
freeSize = 0;
ulong remainder = address % alignment;
if (remainder != 0)
{
address = (address - remainder) + alignment;
}
}
}
return PteUnmapped;
}
internal ulong GetSubSize(ulong gpuVa)
{
ulong size = 0;
while (GetPte(gpuVa + size) != PteUnmapped)
{
size += PageSize;
}
return size;
}
internal ulong Translate(ulong gpuVa)
{
ulong baseAddress = GetPte(gpuVa);
if (baseAddress == PteUnmapped || baseAddress == PteReserved)
{
return PteUnmapped;
}
return baseAddress + (gpuVa & PageMask);
}
public bool IsRegionFree(ulong va, ulong size)
{
for (ulong offset = 0; offset < size; offset += PageSize)
{
if (IsPageInUse(va + offset))
{
return false;
}
}
return true;
}
private bool IsPageInUse(ulong va)
{
if (va >> PtLvl0Bits + PtLvl1Bits + PtPageBits != 0)
{
return false;
}
ulong l0 = (va >> PtLvl0Bit) & PtLvl0Mask;
ulong l1 = (va >> PtLvl1Bit) & PtLvl1Mask;
if (_pageTable[l0] == null)
{
return false;
}
return _pageTable[l0][l1] != PteUnmapped;
}
private ulong GetPte(ulong address)
{
ulong l0 = (address >> PtLvl0Bit) & PtLvl0Mask;
ulong l1 = (address >> PtLvl1Bit) & PtLvl1Mask;
if (_pageTable[l0] == null)
{
return PteUnmapped;
}
return _pageTable[l0][l1];
}
private void SetPte(ulong address, ulong tgtAddr)
{
ulong l0 = (address >> PtLvl0Bit) & PtLvl0Mask;
ulong l1 = (address >> PtLvl1Bit) & PtLvl1Mask;
if (_pageTable[l0] == null)
{
_pageTable[l0] = new ulong[PtLvl1Size];
for (ulong index = 0; index < PtLvl1Size; index++)
{
_pageTable[l0][index] = PteUnmapped;
}
}
_pageTable[l0][l1] = tgtAddr;
}
}
}