OpenE2K
/
qemu-e2k
13
4
Fork 0
Code Issues 4 Pull Requests Projects 2 Releases Activity
qemu-e2k/hw/dma.c

364 lines
8.9 KiB
C
Raw Blame History

/*
* QEMU DMA emulation
*
* Copyright (c) 2003 Vassili Karpov (malc)
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "vl.h"
#define log(...) fprintf (stderr, "dma: " __VA_ARGS__)
#ifdef DEBUG_DMA
#define lwarn(...) fprintf (stderr, "dma: " __VA_ARGS__)
#define linfo(...) fprintf (stderr, "dma: " __VA_ARGS__)
#define ldebug(...) fprintf (stderr, "dma: " __VA_ARGS__)
#else
#define lwarn(...)
#define linfo(...)
#define ldebug(...)
#endif
#define LENOFA(a) ((int) (sizeof(a)/sizeof(a[0])))
struct dma_regs {
int now[2];
uint16_t base[2];
uint8_t mode;
uint8_t page;
uint8_t dack;
uint8_t eop;
DMA_transfer_handler transfer_handler;
void *opaque;
};
#define ADDR 0
#define COUNT 1
static struct dma_cont {
uint8_t status;
uint8_t command;
uint8_t mask;
uint8_t flip_flop;
struct dma_regs regs[4];
} dma_controllers[2];
enum {
CMD_MEMORY_TO_MEMORY = 0x01,
CMD_FIXED_ADDRESS = 0x02,
CMD_BLOCK_CONTROLLER = 0x04,
CMD_COMPRESSED_TIME = 0x08,
CMD_CYCLIC_PRIORITY = 0x10,
CMD_EXTENDED_WRITE = 0x20,
CMD_LOW_DREQ = 0x40,
CMD_LOW_DACK = 0x80,
CMD_NOT_SUPPORTED = CMD_MEMORY_TO_MEMORY | CMD_FIXED_ADDRESS
| CMD_COMPRESSED_TIME | CMD_CYCLIC_PRIORITY | CMD_EXTENDED_WRITE
| CMD_LOW_DREQ | CMD_LOW_DACK
};
static void write_page (void *opaque, uint32_t nport, uint32_t data)
{
int ichan;
int ncont;
static int channels[8] = {-1, 2, 3, 1, -1, -1, -1, 0};
ncont = nport > 0x87;
ichan = channels[nport - 0x80 - (ncont << 3)];
if (-1 == ichan) {
log ("invalid channel %#x %#x\n", nport, data);
return;
}
dma_controllers[ncont].regs[ichan].page = data;
}
static void init_chan (int ncont, int ichan)
{
struct dma_regs *r;
r = dma_controllers[ncont].regs + ichan;
r->now[ADDR] = r->base[0] << ncont;
r->now[COUNT] = 0;
}
static inline int getff (int ncont)
{
int ff;
ff = dma_controllers[ncont].flip_flop;
dma_controllers[ncont].flip_flop = !ff;
return ff;
}
static uint32_t read_chan (void *opaque, uint32_t nport)
{
int ff;
int ncont, ichan, nreg;
struct dma_regs *r;
int val;
ncont = nport > 7;
ichan = (nport >> (1 + ncont)) & 3;
nreg = (nport >> ncont) & 1;
r = dma_controllers[ncont].regs + ichan;
ff = getff (ncont);
if (nreg)
val = (r->base[COUNT] << ncont) - r->now[COUNT];
else
val = r->now[ADDR] + r->now[COUNT];
return (val >> (ncont + (ff << 3))) & 0xff;
}
static void write_chan (void *opaque, uint32_t nport, uint32_t data)
{
int ncont, ichan, nreg;
struct dma_regs *r;
ncont = nport > 7;
ichan = (nport >> (1 + ncont)) & 3;
nreg = (nport >> ncont) & 1;
r = dma_controllers[ncont].regs + ichan;
if (getff (ncont)) {
r->base[nreg] = (r->base[nreg] & 0xff) | ((data << 8) & 0xff00);
init_chan (ncont, ichan);
} else {
r->base[nreg] = (r->base[nreg] & 0xff00) | (data & 0xff);
}
}
static void write_cont (void *opaque, uint32_t nport, uint32_t data)
{
int iport, ichan, ncont;
struct dma_cont *d;
ncont = nport > 0xf;
ichan = -1;
d = dma_controllers + ncont;
if (ncont) {
iport = ((nport - 0xd0) >> 1) + 8;
}
else {
iport = nport;
}
switch (iport) {
case 8: /* command */
if (data && (data | CMD_NOT_SUPPORTED)) {
log ("command %#x not supported\n", data);
goto error;
}
d->command = data;
break;
case 9:
ichan = data & 3;
if (data & 4) {
d->status |= 1 << (ichan + 4);
}
else {
d->status &= ~(1 << (ichan + 4));
}
d->status &= ~(1 << ichan);
break;
case 0xa: /* single mask */
if (data & 4)
d->mask |= 1 << (data & 3);
else
d->mask &= ~(1 << (data & 3));
break;
case 0xb: /* mode */
{
ichan = data & 3;
#ifdef DEBUG_DMA
int op;
int ai;
int dir;
int opmode;
op = (data >> 2) & 3;
ai = (data >> 4) & 1;
dir = (data >> 5) & 1;
opmode = (data >> 6) & 3;
linfo ("ichan %d, op %d, ai %d, dir %d, opmode %d\n",
ichan, op, ai, dir, opmode);
#endif
d->regs[ichan].mode = data;
break;
}
case 0xc: /* clear flip flop */
d->flip_flop = 0;
break;
case 0xd: /* reset */
d->flip_flop = 0;
d->mask = ~0;
d->status = 0;
d->command = 0;
break;
case 0xe: /* clear mask for all channels */
d->mask = 0;
break;
case 0xf: /* write mask for all channels */
d->mask = data;
break;
default:
log ("dma: unknown iport %#x\n", iport);
goto error;
}
#ifdef DEBUG_DMA
if (0xc != iport) {
linfo ("nport %#06x, ncont %d, ichan % 2d, val %#06x\n",
nport, d != dma_controllers, ichan, data);
}
#endif
return;
error:
abort ();
}
int DMA_get_channel_mode (int nchan)
{
return dma_controllers[nchan > 3].regs[nchan & 3].mode;
}
void DMA_hold_DREQ (int nchan)
{
int ncont, ichan;
ncont = nchan > 3;
ichan = nchan & 3;
linfo ("held cont=%d chan=%d\n", ncont, ichan);
dma_controllers[ncont].status |= 1 << (ichan + 4);
}
void DMA_release_DREQ (int nchan)
{
int ncont, ichan;
ncont = nchan > 3;
ichan = nchan & 3;
linfo ("released cont=%d chan=%d\n", ncont, ichan);
dma_controllers[ncont].status &= ~(1 << (ichan + 4));
}
static void channel_run (int ncont, int ichan)
{
struct dma_regs *r;
int n;
target_ulong addr;
/* int ai, dir; */
r = dma_controllers[ncont].regs + ichan;
/* ai = r->mode & 16; */
/* dir = r->mode & 32 ? -1 : 1; */
addr = (r->page << 16) | r->now[ADDR];
n = r->transfer_handler (r->opaque, addr,
(r->base[COUNT] << ncont) + (1 << ncont));
r->now[COUNT] = n;
ldebug ("dma_pos %d size %d\n",
n, (r->base[1] << ncont) + (1 << ncont));
}
void DMA_run (void)
{
struct dma_cont *d;
int icont, ichan;
d = dma_controllers;
for (icont = 0; icont < 2; icont++, d++) {
for (ichan = 0; ichan < 4; ichan++) {
int mask;
mask = 1 << ichan;
if ((0 == (d->mask & mask)) && (0 != (d->status & (mask << 4))))
channel_run (icont, ichan);
}
}
}
void DMA_register_channel (int nchan,
DMA_transfer_handler transfer_handler,
void *opaque)
{
struct dma_regs *r;
int ichan, ncont;
ncont = nchan > 3;
ichan = nchan & 3;
r = dma_controllers[ncont].regs + ichan;
r->transfer_handler = transfer_handler;
r->opaque = opaque;
}
/* request the emulator to transfer a new DMA memory block ASAP */
void DMA_schedule(int nchan)
{
cpu_interrupt(cpu_single_env, CPU_INTERRUPT_EXIT);
}
void DMA_init (void)
{
int i;
int page_port_list[] = { 0x1, 0x2, 0x3, 0x7 };
for (i = 0; i < 8; i++) {
register_ioport_write (i, 1, 1, write_chan, NULL);
register_ioport_write (0xc0 + (i << 1), 1, 1, write_chan, NULL);
register_ioport_read (i, 1, 1, read_chan, NULL);
register_ioport_read (0xc0 + (i << 1), 1, 1, read_chan, NULL);
}
for (i = 0; i < LENOFA (page_port_list); i++) {
register_ioport_write (page_port_list[i] + 0x80, 1, 1, write_page, NULL);
register_ioport_write (page_port_list[i] + 0x88, 1, 1, write_page, NULL);
}
for (i = 0; i < 8; i++) {
register_ioport_write (i + 8, 1, 1, write_cont, NULL);
register_ioport_write (0xd0 + (i << 1), 1, 1, write_cont, NULL);
}
write_cont (NULL, 0x0d, 0);
write_cont (NULL, 0xda, 0);
}
Reference in New Issue View Git Blame Copy Permalink