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clem_mem.c
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clem_mem.c
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#include "clem_mem.h"
#include "clem_debug.h"
#include "clem_shared.h"
// these are inlined headers
#include "clem_cycle.h"
#include "clem_util.h"
void clem_mem_create_page_mapping(struct ClemensMemoryPageInfo *page, uint8_t page_idx,
uint8_t bank_read_idx, uint8_t bank_write_idx) {
page->flags = CLEM_MEM_PAGE_WRITEOK_FLAG;
page->bank_read = bank_read_idx;
page->read = page_idx;
page->bank_write = bank_write_idx;
page->write = page_idx;
}
void clem_read(ClemensMachine *clem, uint8_t *data, uint16_t adr, uint8_t bank, uint8_t flags) {
struct ClemensMemoryPageMap *bank_page_map = clem->mem.bank_page_map[bank];
struct ClemensMemoryPageInfo *page = &bank_page_map->pages[adr >> 8];
uint16_t offset = ((uint16_t)page->read << 8) | (adr & 0xff);
bool read_only = (flags == CLEM_MEM_FLAG_NULL);
bool mega2_access = false;
bool io_access = false;
// TODO: store off if read_reg has a read_count of 1 here
// reset it automatically if true at the end of this function
if (page->flags & CLEM_MEM_IO_MEMORY_MASK) {
unsigned slot_idx;
io_access = true;
if (page->flags & CLEM_MEM_PAGE_IOADDR_FLAG) {
if (offset >= 0xc071 && offset < 0xc080) {
*data = clem->mem.fpi_bank_map[0xff][offset];
io_access = false;
} else {
*data = (*clem->mem.mmio_read)(&clem->mem, &clem->tspec, offset,
read_only ? CLEM_OP_IO_NO_OP : 0, &mega2_access);
}
} else if (page->flags & CLEM_MEM_PAGE_CARDMEM_FLAG) {
*data = (*clem->mem.mmio_read)(
&clem->mem, &clem->tspec, ((uint16_t)page->read << 8) | (adr & 0xff),
(read_only ? CLEM_OP_IO_NO_OP : 0) | CLEM_OP_IO_CARD, &mega2_access);
} else {
CLEM_ASSERT(false);
}
} else if (!(page->flags & CLEM_MEM_PAGE_TYPE_MASK) ||
(page->flags & CLEM_MEM_PAGE_BANK_MASK)) {
uint8_t *bank_mem;
uint8_t bank_actual;
if (page->flags & CLEM_MEM_PAGE_DIRECT_FLAG) {
bank_actual = bank;
} else if (page->flags & CLEM_MEM_PAGE_MAINAUX_FLAG) {
bank_actual = (bank & 0xfe) | (page->bank_read & 0x1);
} else {
bank_actual = page->bank_read;
}
bank_mem = _clem_get_memory_bank(clem, bank_actual, &mega2_access);
// TODO: when reading from e0/e1 banks, is it always slow?
// internal ROM, peripheral?
if (bank_actual == 0xe0 || bank_actual == 0xe1) {
mega2_access = true;
}
*data = bank_mem[offset];
} else {
CLEM_ASSERT(false);
}
if (!read_only) {
// TODO: account for slow/fast memory access
clem->cpu.pins.adr = adr;
clem->cpu.pins.bank = bank;
clem->cpu.pins.data = *data;
clem->cpu.pins.vpaOut = (flags & CLEM_MEM_FLAG_PROGRAM) != 0;
clem->cpu.pins.vdaOut = (flags & CLEM_MEM_FLAG_DATA) != 0;
clem->cpu.pins.rwbOut = true;
clem->cpu.pins.ioOut = io_access;
_clem_mem_cycle(clem, mega2_access);
}
}
void clem_write(ClemensMachine *clem, uint8_t data, uint16_t adr, uint8_t bank, uint8_t mem_flags) {
struct ClemensMemoryPageMap **bank_map = clem->mem.bank_page_map;
struct ClemensMemoryPageMap *bank_page_map = bank_map[bank];
struct ClemensMemoryShadowMap *shadow_map;
struct ClemensMemoryPageInfo *page = &bank_page_map->pages[adr >> 8];
uint16_t offset;
uint8_t flags = mem_flags == CLEM_MEM_FLAG_NULL ? CLEM_OP_IO_NO_OP : 0;
bool mega2_access = false;
bool io_access = false;
if (page->flags & CLEM_MEM_IO_MEMORY_MASK) {
unsigned slot_idx;
offset = ((uint16_t)page->write << 8) | (adr & 0xff);
if (page->flags & CLEM_MEM_PAGE_IOADDR_FLAG) {
if (page->flags & CLEM_MEM_PAGE_WRITEOK_FLAG) {
(*clem->mem.mmio_write)(&clem->mem, &clem->tspec, data, offset, flags,
&mega2_access);
} else {
mega2_access = true;
}
} else if (page->flags & CLEM_MEM_PAGE_CARDMEM_FLAG) {
(*clem->mem.mmio_write)(&clem->mem, &clem->tspec, data,
((uint16_t)page->write << 8) | (adr & 0xff),
flags | CLEM_OP_IO_CARD, &mega2_access);
} else {
CLEM_ASSERT(false);
}
io_access = true;
} else if (!(page->flags & CLEM_MEM_PAGE_TYPE_MASK) ||
(page->flags & CLEM_MEM_PAGE_BANK_MASK)) {
uint8_t *bank_mem;
uint8_t bank_actual;
if (page->flags & CLEM_MEM_PAGE_DIRECT_FLAG) {
bank_actual = bank;
} else if (page->flags & CLEM_MEM_PAGE_MAINAUX_FLAG) {
bank_actual = (bank & 0xfe) | (page->bank_write & 0x1);
} else {
bank_actual = page->bank_write;
}
bank_page_map = bank_map[bank_actual];
shadow_map = bank_page_map->shadow_map;
page = &bank_page_map->pages[adr >> 8];
bank_mem = _clem_get_memory_bank(clem, bank_actual, &mega2_access);
offset = ((uint16_t)page->write << 8) | (adr & 0xff);
if (page->flags & CLEM_MEM_PAGE_WRITEOK_FLAG) {
bank_mem[offset] = data;
}
if (shadow_map && shadow_map->pages[page->write]) {
bank_mem = _clem_get_memory_bank(clem, (0xE0) | (bank_actual & 0x1), &mega2_access);
if (page->flags & CLEM_MEM_PAGE_WRITEOK_FLAG) {
bank_mem[offset] = data;
}
}
if (bank_actual == 0xe0 || bank_actual == 0xe1) {
mega2_access = true;
}
} else {
CLEM_ASSERT(false);
}
if (mem_flags != CLEM_MEM_FLAG_NULL) {
clem->cpu.pins.adr = adr;
clem->cpu.pins.bank = bank;
clem->cpu.pins.data = data;
clem->cpu.pins.vpaOut = false;
clem->cpu.pins.vdaOut = (mem_flags & CLEM_MEM_FLAG_DATA) != 0;
clem->cpu.pins.rwbOut = false;
clem->cpu.pins.ioOut = io_access;
_clem_mem_cycle(clem, mega2_access);
}
}