mirror of
https://github.com/rkujawa/rk65c02.git
synced 2024-12-23 07:30:31 +00:00
Refactor bus reads and writes to split common code.
This commit is contained in:
parent
1f072e1b11
commit
edab91de3f
64
src/bus.c
64
src/bus.c
@ -16,6 +16,8 @@
|
||||
|
||||
#define RK65C02_BUS_SIZE 64*1024
|
||||
|
||||
static void bus_access_device(bus_t *, uint16_t, device_t **, uint16_t *);
|
||||
|
||||
void
|
||||
bus_device_add(bus_t *b, device_t *d, uint16_t addr)
|
||||
{
|
||||
@ -43,58 +45,64 @@ bus_device_dump(bus_t *b)
|
||||
}
|
||||
}
|
||||
|
||||
uint8_t
|
||||
bus_read_1(bus_t *t, uint16_t addr)
|
||||
/*
|
||||
* Determine which device is accessed and at what offset. The d argument is
|
||||
* filled with pointer to accessed device, off with offset.
|
||||
* Returns device NULL when hitting unmapped space.
|
||||
*/
|
||||
static void
|
||||
bus_access_device(bus_t *t, uint16_t addr, device_t **d, uint16_t *off)
|
||||
{
|
||||
uint8_t val;
|
||||
uint16_t doff;
|
||||
device_mapping_t *dm;
|
||||
device_t *dtmp, *d;
|
||||
device_t *dtmp;
|
||||
|
||||
d = NULL;
|
||||
*d = NULL;
|
||||
|
||||
LL_FOREACH(t->dm_head, dm) {
|
||||
dtmp = dm->dev;
|
||||
if ( (addr >= dm->addr) && (addr < (dm->addr + dtmp->size)) ) {
|
||||
d = dtmp;
|
||||
*d = dtmp;
|
||||
doff = dm->addr;
|
||||
}
|
||||
}
|
||||
|
||||
if (d == NULL) {
|
||||
if (*d == NULL) {
|
||||
fprintf(stderr, "Hitting unmapped bus space @ %x!", addr);
|
||||
return 0xFF;
|
||||
return;
|
||||
}
|
||||
|
||||
val = d->read_1(d, addr - doff);
|
||||
*off = addr - doff;
|
||||
}
|
||||
|
||||
printf("bus READ @ %x (off %x) value %x\n", addr, addr - doff, val);
|
||||
uint8_t
|
||||
bus_read_1(bus_t *t, uint16_t addr)
|
||||
{
|
||||
uint8_t val;
|
||||
uint16_t off;
|
||||
device_t *d;
|
||||
|
||||
bus_access_device(t, addr, &d, &off);
|
||||
|
||||
if (d == NULL)
|
||||
return 0xFF;
|
||||
else
|
||||
val = d->read_1(d, off);
|
||||
|
||||
printf("bus READ @ %x (off %x) value %x\n", addr, off, val);
|
||||
return val;
|
||||
}
|
||||
|
||||
void
|
||||
bus_write_1(bus_t *t, uint16_t addr, uint8_t val)
|
||||
{
|
||||
uint16_t doff;
|
||||
device_mapping_t *dm;
|
||||
device_t *dtmp, *d;
|
||||
uint16_t off;
|
||||
device_t *d;
|
||||
|
||||
d = NULL;
|
||||
bus_access_device(t, addr, &d, &off);
|
||||
|
||||
LL_FOREACH(t->dm_head, dm) {
|
||||
dtmp = dm->dev;
|
||||
if ( (addr >= dm->addr) && (addr < (dm->addr + dtmp->size)) ) {
|
||||
d = dtmp;
|
||||
doff = dm->addr;
|
||||
}
|
||||
}
|
||||
|
||||
if (d == NULL) {
|
||||
fprintf(stderr, "Hitting unmapped bus space @ %x!", addr);
|
||||
}
|
||||
|
||||
printf("bus WRITE @ %x (off %x) value %x\n", addr, addr - doff, val);
|
||||
d->write_1(d, addr - doff, val);
|
||||
printf("bus WRITE @ %x (off %x) value %x\n", addr, off, val);
|
||||
d->write_1(d, off, val);
|
||||
}
|
||||
|
||||
bus_t
|
||||
|
Loading…
Reference in New Issue
Block a user