MMU: fix rollback in DSIs on page-crossing stores

I don't know if this affected anything, but it was subtly wrong.
Also reorganize the loads to match, for consistency.
This commit is contained in:
Fiora 2015-01-01 12:38:43 -08:00
parent acb583e607
commit ea23ce2726

View File

@ -130,43 +130,35 @@ __forceinline void ReadFromHardware(U &_var, const u32 em_address, Memory::XChec
// Handle loads that cross page boundaries (ewwww)
if (sizeof(T) > 1 && (em_address & (HW_PAGE_SIZE - 1)) > HW_PAGE_SIZE - sizeof(T))
{
_var = 0;
// This could be unaligned down to the byte level... hopefully this is rare, so doing it this
// way isn't too terrible.
// TODO: floats on non-word-aligned boundaries should technically cause alignment exceptions.
// Note that "word" means 32-bit, so paired singles or doubles might still be 32-bit aligned!
u32 tlb_addr = TranslateAddress(em_address, flag);
u32 em_address_next_page = (em_address + sizeof(T) - 1) & ~(HW_PAGE_SIZE - 1);
u32 tlb_addr_next_page = TranslateAddress(em_address_next_page, flag);
if (tlb_addr == 0 || tlb_addr_next_page == 0)
{
if (flag == FLAG_READ)
{
u32 exception_addr = tlb_addr == 0 ? em_address : em_address_next_page;
if (!SConfig::GetInstance().m_LocalCoreStartupParameter.bMMU)
PanicAlertT("Invalid Read at 0x%08x, PC = 0x%08x ", exception_addr, PC);
else
GenerateDSIException(exception_addr, false);
}
return;
}
_var = 0;
for (u32 addr = em_address; addr < em_address + sizeof(T); addr++, tlb_addr++)
{
// Start of the new page... translate the address again!
if (!(addr & (HW_PAGE_SIZE-1)))
tlb_addr = TranslateAddress(addr, flag);
// Important: we need to generate the DSI on the first store that caused the fault, NOT
// the address of the start of the load.
if (tlb_addr == 0)
{
if (flag == FLAG_READ)
{
if (!SConfig::GetInstance().m_LocalCoreStartupParameter.bMMU)
PanicAlertT("Invalid Read at 0x%08x, PC = 0x%08x ", em_address, PC);
else
GenerateDSIException(addr, false);
break;
}
}
if (addr == em_address_next_page)
tlb_addr = tlb_addr_next_page;
_var <<= 8;
if (m_pEXRAM && (tlb_addr & 0xF0000000) == 0x10000000)
_var |= m_pEXRAM[tlb_addr & EXRAM_MASK];
else
{
if (m_pEXRAM && (tlb_addr & 0xF0000000) == 0x10000000)
{
_var <<= 8;
_var |= m_pEXRAM[tlb_addr & EXRAM_MASK];
}
else
{
_var <<= 8;
_var |= m_pRAM[tlb_addr & RAM_MASK];
}
}
_var |= m_pRAM[tlb_addr & RAM_MASK];
}
}
else
@ -271,35 +263,30 @@ __forceinline void WriteToHardware(u32 em_address, const T data, Memory::XCheckT
if (sizeof(T) > 1 && (em_address & (HW_PAGE_SIZE-1)) > HW_PAGE_SIZE - sizeof(T))
{
T val = bswap(data);
// We need to check both addresses before writing in case there's a DSI.
u32 tlb_addr = TranslateAddress(em_address, flag);
for (u32 addr = em_address; addr < em_address + sizeof(T); addr++, tlb_addr++)
u32 em_address_next_page = (em_address + sizeof(T) - 1) & ~(HW_PAGE_SIZE - 1);
u32 tlb_addr_next_page = TranslateAddress(em_address_next_page, flag);
if (tlb_addr == 0 || tlb_addr_next_page == 0)
{
if (!(addr & (HW_PAGE_SIZE-1)))
tlb_addr = TranslateAddress(addr, flag);
if (tlb_addr == 0)
if (flag == FLAG_WRITE)
{
if (flag == FLAG_WRITE)
{
if (!SConfig::GetInstance().m_LocalCoreStartupParameter.bMMU)
PanicAlertT("Invalid Write to 0x%08x, PC = 0x%08x ", em_address, PC);
else
GenerateDSIException(addr, true);
break;
}
}
else
{
if (m_pEXRAM && (tlb_addr & 0xF0000000) == 0x10000000)
{
m_pEXRAM[tlb_addr & EXRAM_MASK] = (u8)val;
val >>= 8;
}
u32 exception_addr = tlb_addr == 0 ? em_address : em_address_next_page;
if (!SConfig::GetInstance().m_LocalCoreStartupParameter.bMMU)
PanicAlertT("Invalid Write to 0x%08x, PC = 0x%08x ", exception_addr, PC);
else
{
m_pRAM[tlb_addr & RAM_MASK] = (u8)val;
val >>= 8;
}
GenerateDSIException(exception_addr, true);
}
return;
}
for (u32 addr = em_address; addr < em_address + sizeof(T); addr++, tlb_addr++, val >>= 8)
{
if (addr == em_address_next_page)
tlb_addr = tlb_addr_next_page;
if (m_pEXRAM && (tlb_addr & 0xF0000000) == 0x10000000)
m_pEXRAM[tlb_addr & EXRAM_MASK] = (u8)val;
else
m_pRAM[tlb_addr & RAM_MASK] = (u8)val;
}
}
else