2009-05-18 10:03:15 +02:00

128 lines
3.5 KiB
C++
Executable File

#include <../base.hpp>
#define MEMORY_CPP
namespace memory {
MMIOAccess mmio;
StaticRAM wram(128 * 1024);
StaticRAM apuram(64 * 1024);
StaticRAM vram(64 * 1024);
StaticRAM oam(544);
StaticRAM cgram(512);
UnmappedMemory memory_unmapped;
UnmappedMMIO mmio_unmapped;
};
uint8 UnmappedMemory::read(unsigned) { return cpu.regs.mdr; }
void UnmappedMemory::write(unsigned addr, uint8 val) {
//printf("UnmappedMemory::write 0x%x 0x%x\n",addr,val);
}
uint8 UnmappedMMIO::mmio_read(unsigned) { return cpu.regs.mdr; }
void UnmappedMMIO::mmio_write(unsigned addr, uint8 val) {
//printf("UnmappedMemory::write 0x%x 0x%x\n",addr,val);
}
void MMIOAccess::map(unsigned addr, MMIO &access) {
//printf("MMIOAccess::map 0x%x\n",addr);
//MMIO: $[00-3f]:[2000-5fff]
mmio[(addr - 0x2000) & 0x3fff] = &access;
}
MMIO* MMIOAccess::get(unsigned addr) {
return mmio[(addr - 0x2000) & 0x3fff];
}
uint8 MMIOAccess::read(unsigned addr) {
//printf("MMIOAccess::read 0x%x\n",addr);
return mmio[(addr - 0x2000) & 0x3fff]->mmio_read(addr);
}
void MMIOAccess::write(unsigned addr, uint8 data) {
//printf("MMIOAccess::write 0x%x %x\n",addr,data);
mmio[(addr - 0x2000) & 0x3fff]->mmio_write(addr, data);
}
unsigned Bus::mirror(unsigned addr, unsigned size) {
unsigned base = 0;
if(size) {
unsigned mask = 1 << 23;
while(addr >= size) {
while(!(addr & mask)) mask >>= 1;
addr -= mask;
if(size > mask) {
size -= mask;
base += mask;
}
mask >>= 1;
}
base += addr;
}
return base;
}
void Bus::map(unsigned addr, Memory &access, unsigned offset) {
page[addr >> 8].access = &access;
page[addr >> 8].offset = offset - addr;
}
void Bus::map(
MapMode mode,
uint8 bank_lo, uint8 bank_hi,
uint16 addr_lo, uint16 addr_hi,
Memory &access, unsigned offset, unsigned size
) {
assert(bank_lo <= bank_hi);
assert(addr_lo <= addr_hi);
if(access.size() == -1U) return;
uint8 page_lo = addr_lo >> 8;
uint8 page_hi = addr_hi >> 8;
unsigned index = 0;
switch(mode) {
case MapDirect: {
printf("Bus::map MapDirect bank_lo=0x%02x bank_hi=0x%02x addr_lo=0x%04x addr_hi=0x%04x\n",
bank_lo,bank_hi,addr_lo,addr_hi);
for(unsigned bank = bank_lo; bank <= bank_hi; bank++) {
for(unsigned page = page_lo; page <= page_hi; page++) {
map((bank << 16) + (page << 8), access, (bank << 16) + (page << 8));
}
}
} break;
case MapLinear: {
printf("Bus::map MapLinear bank_lo=0x%02x bank_hi=0x%02x addr_lo=0x%04x addr_hi=0x%04x\n",
bank_lo,bank_hi,addr_lo,addr_hi);
for(unsigned bank = bank_lo; bank <= bank_hi; bank++) {
for(unsigned page = page_lo; page <= page_hi; page++) {
map((bank << 16) + (page << 8), access, mirror(offset + index, access.size()));
index += 256;
if(size) index %= size;
}
}
} break;
case MapShadow: {
printf("Bus::map MapShadow bank_lo=0x%02x bank_hi=0x%02x addr_lo=0x%04x addr_hi=0x%04x\n",
bank_lo,bank_hi,addr_lo,addr_hi);
for(unsigned bank = bank_lo; bank <= bank_hi; bank++) {
index += page_lo * 256;
if(size) index %= size;
for(unsigned page = page_lo; page <= page_hi; page++) {
map((bank << 16) + (page << 8), access, mirror(offset + index, access.size()));
index += 256;
if(size) index %= size;
}
index += (255 - page_hi) * 256;
if(size) index %= size;
}
} break;
}
}