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Integrate JoyBus checksum

This commit is contained in:
Jack Andersen 2016-12-31 20:56:34 -10:00
parent 0d4ea76c7f
commit 02a3b8a6e7
1 changed files with 33 additions and 2 deletions
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35
Runtime/MP1/CGBASupport.cpp
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@ -21,6 +21,11 @@ namespace MP1
#define GBA_JOYBOOT_UNKNOWN_STATE 3
#define GBA_JOYBOOT_ERR_INVALID 4
static void GBAInit()
{
}
static s32 GBAJoyBootAsync(s32 chan, s32 paletteColor, s32 paletteSpeed,
u8* programp, s32 length, u8* status)
{
@ -52,6 +57,30 @@ static s32 GBAWrite(s32 chan, u8* src, u8* status)
return GBA_READY;
}
static u32 calculateJBusChecksum(const u8* data, size_t len)
{
const u8* ptr = data;
u32 sum = -1;
for (int i = len ; i > 0; --i)
{
u8 ch = *ptr;
ptr++;
sum ^= ch;
for (int j = 0; j < 8; ++j)
{
if ((sum & 1))
{
sum >>= 1;
sum ^= 0xb010;
}
else
sum >>= 1;
}
}
return sum;
}
CGBASupport* CGBASupport::SharedInstance = nullptr;
CGBASupport::CGBASupport()
@ -60,7 +89,7 @@ CGBASupport::CGBASupport()
x28_fileSize = ROUND_UP_32(Length());
x2c_buffer.reset(new u8[x28_fileSize]);
x30_dvdReq = AsyncRead(x2c_buffer.get(), x28_fileSize);
//GBAInit();
GBAInit();
SharedInstance = this;
}
@ -123,7 +152,9 @@ bool CGBASupport::PollResponse()
if (GBARead(x40_siChan, bytes, &status) != GBA_READY)
return false;
/* CRC Here */
u32 swapped = hecl::SBig(reinterpret_cast<u32&>(bytes));
if (bytes[0] != calculateJBusChecksum(reinterpret_cast<u8*>(&swapped), 3))
return false;
x44_fusionLinked = (bytes[2] & 0x2) != 0;
if (x44_fusionLinked && (bytes[2] & 0x1) != 0)