Implement oam dma
This commit is contained in:
parent
e6c5e00908
commit
fe0a183ae5
17
include/gb.h
17
include/gb.h
|
|
@ -44,18 +44,25 @@ void gb_joypad_update(GBJoypad *joypad);
|
|||
void gb_joypad_close(GBJoypad *joypad, RIO *io);
|
||||
|
||||
typedef struct gb_dma_t {
|
||||
ut64 seek; //17 bit seek and some flags
|
||||
int dma_fd; //fd representing the dma register
|
||||
int dma_bus_fd; //fd representing the memory bus while dma occupies it
|
||||
ut16 bus_occupancy_size;
|
||||
ut32 dma_bank_id;
|
||||
ut32 default_bank_id;
|
||||
// ut16 bus_occupancy_size;
|
||||
ut8 buf[0xa0];
|
||||
ut8 dst; //current dst addr low byte
|
||||
ut8 todo; //cycles todo
|
||||
ut8 frontrun; //cycles that read/write ops had frontrun the dma copy
|
||||
// ut8 todo; //cycles todo
|
||||
st8 frontrun; //cycles that read/write ops had frontrun the dma copy
|
||||
ut8 val;
|
||||
} GBDMA;
|
||||
|
||||
GBDMA *gb_dma_open(RIO *io);
|
||||
void gb_dma_update(GBDMA *dma, RIO *io, ut32 cycles);
|
||||
#define GB_DMA_LAUNCH 0x20000
|
||||
#define GB_DMA_RUNNING 0x40000
|
||||
#define GB_DMA_ACTIVE 0x60000
|
||||
|
||||
GBDMA *gb_dma_open(RIO *io, bool cgb);
|
||||
void gb_dma_update(GBDMA *dma, RIO *io, ut32 cycles, bool pre_exec);
|
||||
void gb_dma_close(GBDMA *dma, RIO *io);
|
||||
|
||||
extern RIOPlugin r_io_plugin_gb_timers;
|
||||
|
|
|
|||
250
io/dma.c
Normal file
250
io/dma.c
Normal file
|
|
@ -0,0 +1,250 @@
|
|||
#include <stdio.h>
|
||||
#include <gb.h>
|
||||
#include <r_io.h>
|
||||
#include <r_util.h>
|
||||
|
||||
RIOPlugin r_io_plugin_gb_dma;
|
||||
RIOPlugin r_io_plugin_gb_dma_bus;
|
||||
|
||||
static ut64 __bus_lseek(RIO* io, RIODesc *desc, ut64 offset, int whence) {
|
||||
GBDMA *dma = desc->data;
|
||||
ut64 seek = dma->seek & 0xffff;
|
||||
switch (whence) {
|
||||
case R_IO_SEEK_SET:
|
||||
seek = R_MIN (0xff80, offset);
|
||||
break;
|
||||
case R_IO_SEEK_CUR:
|
||||
seek = R_MIN (0xff80, seek + offset);
|
||||
break;
|
||||
case R_IO_SEEK_END:
|
||||
seek = 0xff80;
|
||||
break
|
||||
}
|
||||
dma->seek = (dma->seek & (~0xffff)) | seek;
|
||||
return seek;
|
||||
}
|
||||
|
||||
static bool __bus_check(RIO *io, const char *pathname, bool many) {
|
||||
return r_str_startswith (pathname, "gb_dma_bus://");
|
||||
}
|
||||
|
||||
static int __bus_read(RIO *io, RIODesc *desc, ut8 *buf, int len) {
|
||||
GBDMA *dma = desc->data;
|
||||
ut64 seek = dma->seek & 0xffff;
|
||||
if (timers->seek > 0xff7f || len < 1) {
|
||||
return 0;
|
||||
}
|
||||
len = R_MIN (len, 0xff80 - seek);
|
||||
int _len = R_MIN (len, 0xa0 - ((ut32)dma->dst + (st32)dma->frontrun));
|
||||
memcpy (buf, &dma->buf[dma->dst + dma->frontrun], _len);
|
||||
dma->frontrun += _len;
|
||||
#if 1
|
||||
if (len != _len) {
|
||||
ut64 vseek = r_io_p2v (io, seek + _len);
|
||||
r_io_bank_read_at (io, dma->default_bank_id, &buf[_len], len - _len)
|
||||
}
|
||||
#endif
|
||||
seek += len;
|
||||
dma->seek = (dma->seek & (~0xffff)) | seek;
|
||||
return len;
|
||||
}
|
||||
|
||||
static int __bus_write(RIO *io, RIODesc *desc, const ut8 *buf, int len) {
|
||||
GBDMA *dma = desc->data;
|
||||
ut64 seek = dma->seek & 0xffff;
|
||||
if (timers->seek > 0xff7f || len < 1) {
|
||||
return 0;
|
||||
}
|
||||
len = R_MIN (len, 0xff80 - seek);
|
||||
int _len = R_MIN (len, 0xa0 - ((ut32)dma->dst + (st32)dma->frontrun));
|
||||
// memcpy (buf, &dma->buf[dma->dst + dma->frontrun], _len);
|
||||
dma->frontrun += _len;
|
||||
#if 0
|
||||
if (len != _len) {
|
||||
ut64 vseek = r_io_p2v (io, seek + _len);
|
||||
r_io_bank_write_at (io, dma->default_bank_id, &buf[_len], len - _len)
|
||||
}
|
||||
#endif
|
||||
seek += len;
|
||||
dma->seek = (dma->seek & (~0xffff)) | seek;
|
||||
return len;
|
||||
}
|
||||
|
||||
static bool __close(RIODesc *desc) {
|
||||
return true;
|
||||
}
|
||||
|
||||
static RIODesc *__bus_open(RIO *io, const char *pathname, int rw, int mode) {
|
||||
if (!r_str_startswith (pathname, "gb_dma_bus://")) {
|
||||
return NULL;
|
||||
}
|
||||
GBDMA *dma = NULL;
|
||||
sscanf (pathname, "gb_dma_bus://%p", &dma);
|
||||
RIODesc *desc = r_io_desc_new (io, &r_io_plugin_gb_dma_bus, pathname,
|
||||
R_PERM_RWX, mode, dma);
|
||||
return desc;
|
||||
}
|
||||
|
||||
RIOPlugin r_io_plugin_gb_dma_bus = {
|
||||
.meta = {
|
||||
.name = "gb_dma_bus",
|
||||
.desc = "gb_dma_bus",
|
||||
.license = "LGPL",
|
||||
},
|
||||
.uris = "gb_dma_bus://",
|
||||
.open = __bus_open,
|
||||
.close = __close,
|
||||
.read = __bus_read,
|
||||
.check = __bus_check,
|
||||
.seek = __bus_lseek,
|
||||
.write = __bus_write,
|
||||
};
|
||||
|
||||
static bool __check(RIO *io, const char *pathname, bool many) {
|
||||
return r_str_startswith (pathname, "gb_dma://");
|
||||
}
|
||||
|
||||
static RIODesc *__open(RIO *io, const char *pathname, int rw, int mode) {
|
||||
if (!r_str_startswith (pathname, "gb_dma://")) {
|
||||
return NULL;
|
||||
}
|
||||
GBDMA *dma = NULL;
|
||||
sscanf (pathname, "gb_dma://%p", &dma);
|
||||
RIODesc *desc = r_io_desc_new (io, &r_io_plugin_gb_dma_bus, pathname,
|
||||
R_PERM_RWX, mode, dma);
|
||||
return desc;
|
||||
}
|
||||
|
||||
static ut64 __lseek(RIO* io, RIODesc *desc, ut64 offset, int whence) {
|
||||
GBDMA *dma = desc->data;
|
||||
ut64 seek = (dma->seek & 0x10000) >> 16;
|
||||
switch (whence) {
|
||||
case R_IO_SEEK_SET:
|
||||
seek = R_MIN (1, offset);
|
||||
break;
|
||||
case R_IO_SEEK_CUR:
|
||||
seek = R_MIN (1, seek + offset);
|
||||
break;
|
||||
case R_IO_SEEK_END:
|
||||
seek = 1;
|
||||
break;
|
||||
}
|
||||
dma->seek = (dma->seek & (~0x10000)) | (seek << 16);
|
||||
return seek;
|
||||
}
|
||||
|
||||
static int __read(RIO *io, RIODesc *desc, ut8 *buf, int len) {
|
||||
GBDMA *dma = desc->data;
|
||||
if (!len || (dma->seek & 0x10000)) {
|
||||
return 0;
|
||||
}
|
||||
buf[0] = dma->val;
|
||||
dma->seek |= 0x10000;
|
||||
return 1;
|
||||
}
|
||||
|
||||
static int __write(RIO *io, RIODesc *desc, const ut8 *buf, int len) {
|
||||
GBDMA *dma = desc->data;
|
||||
if (!len || (dma->seek & 0x10000)) {
|
||||
return 0;
|
||||
}
|
||||
dma->val = buf[0];
|
||||
dma->seek |= 0x10000;
|
||||
if (R_LIKELY (!(dma->seek & GB_DMA_RUNNING) && dma->val < 0xe0)) {
|
||||
dma->seek |= GB_DMA_LAUNCH;
|
||||
}
|
||||
return 1;
|
||||
}
|
||||
|
||||
RIOPlugin r_io_plugin_gb_dma = {
|
||||
.meta = {
|
||||
.name = "gb_dma",
|
||||
.desc = "gb_dma",
|
||||
.license = "LGPL",
|
||||
},
|
||||
.uris = "gb_dma://",
|
||||
.open = __open,
|
||||
.close = __close,
|
||||
.read = __read,
|
||||
.check = __check,
|
||||
.seek = __lseek,
|
||||
.write = __write,
|
||||
};
|
||||
|
||||
GBDMA *gb_dma_open (RIO *io, bool cgb) {
|
||||
GBDMA *dma = R_NEW0 (GBDMA);
|
||||
if (!dma) {
|
||||
return NULL;
|
||||
}
|
||||
dma->default_bank_id = io->bank;
|
||||
RIOBank *bank = r_io_bank_new (io, "dma bus");
|
||||
if (!bank) {
|
||||
free (dma);
|
||||
return NULL;
|
||||
}
|
||||
if (!r_io_bank_add (io, bank)) {
|
||||
r_io_bank_free (bank);
|
||||
free (dma);
|
||||
return NULL;
|
||||
}
|
||||
dma->dma_bank_id = bank->id;
|
||||
char uri[64];
|
||||
memset (uri, 0x00, sizeof (char) * 64);
|
||||
sprintf (uri, "gb_dma://%p", dma);
|
||||
RIODesc *desc = r_io_desc_open_plugin (io, &r_io_plugin_gb_dma,
|
||||
uri, R_PERM_RWX, 0);
|
||||
if (!desc) {
|
||||
r_io_bank_free (bank);
|
||||
free (dma);
|
||||
return NULL;
|
||||
}
|
||||
dma->dma_fd = desc->fd;
|
||||
sprintf (uri, "gb_dma_bus://%p", dma);
|
||||
desc = r_io_desc_open_plugin (io, &r_io_plugin_gb_dma_bus, uri, R_PERM_RWX, 0);
|
||||
if (!desc) {
|
||||
r_io_fd_close (dma->dma_fd);
|
||||
r_io_bank_free (bank);
|
||||
free (dma);
|
||||
return NULL;
|
||||
}
|
||||
dma->dma_bus_fd = desc->fd;
|
||||
return dma;
|
||||
}
|
||||
|
||||
void gb_dma_update (GBDMA *dma, RIO *io, ut32 cycles, bool pre_exec) {
|
||||
if (!(dma->seek & GB_DMA_ACTIVE)) {
|
||||
return;
|
||||
}
|
||||
cycles = cycles >> 2;
|
||||
if (!cycles) {
|
||||
return;
|
||||
}
|
||||
if (dma->seek & GB_DMA_LAUNCH) {
|
||||
r_io_read_at (io, dma->val << 8, dma->buf, 0xa0);
|
||||
dma->seek &= (~GB_DMA_LAUNCH);
|
||||
dma->dst = 0;
|
||||
r_io_bank_use (io, dma->dma_bank_id);
|
||||
cycles--;
|
||||
dma->seek |= GB_DMA_RUNNING;
|
||||
if (!cycles) {
|
||||
dma->frontrun = 0;
|
||||
return;
|
||||
}
|
||||
}
|
||||
cycles = R_MIN (0xa0 - dma->dst, cycles);
|
||||
if (pre_exec) {
|
||||
dma->frontrun = ((st32)cycles) * (-1);
|
||||
}
|
||||
if (cycles) {
|
||||
r_io_bank_write_at (io, dma->default_bank_id, 0xfe00 | dma->dst,
|
||||
&dma->buf[dma->dst], cycles);
|
||||
dma->dst += cycles;
|
||||
}
|
||||
if (pre_exec) {
|
||||
return;
|
||||
}
|
||||
if (dma->dst >= 0xa0) {
|
||||
r_io_bank_use (io, dma->default_bank_id);
|
||||
dma->seek &= (~GB_DMA_ACTIVE);
|
||||
}
|
||||
}
|
||||
|
|
@ -42,7 +42,10 @@ static int __read(RIO *io, RIODesc *desc, ut8 *buf, int len) {
|
|||
if (!len || (joypad->odata & 0x40)) {
|
||||
return 0;
|
||||
}
|
||||
#if 0
|
||||
joypad->data = buf[0] & 0xf;
|
||||
#else
|
||||
buf[0] = joypad->data & 0x3f
|
||||
joypad->odata |= 0x40;
|
||||
return 1;
|
||||
}
|
||||
|
|
|
|||
Loading…
Reference in New Issue
Block a user