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Tag: 20121227
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/*
* QEMU DMA emulation
*
* Copyright (c) 2003-2004 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 "hw.h"
#include "isa.h"
/* #define DEBUG_DMA */
#define dolog(...) fprintf (stderr, "dma: " __VA_ARGS__)
#ifdef DEBUG_DMA
#define linfo(...) fprintf (stderr, "dma: " __VA_ARGS__)
#define ldebug(...) fprintf (stderr, "dma: " __VA_ARGS__)
#else
#define linfo(...)
#define ldebug(...)
#endif
struct dma_regs {
int now[2];
uint16_t base[2];
uint8_t mode;
uint8_t page;
uint8_t pageh;
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;
int dshift;
struct dma_regs regs[4];
qemu_irq *cpu_request_exit;
} 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 DMA_run (void);
static int channels[8] = {-1, 2, 3, 1, -1, -1, -1, 0};
static void write_page (void *opaque, uint32_t nport, uint32_t data)
{
struct dma_cont *d = opaque;
int ichan;
ichan = channels[nport & 7];
if (-1 == ichan) {
dolog ("invalid channel %#x %#x\n", nport, data);
return;
}
d->regs[ichan].page = data;
}
static void write_pageh (void *opaque, uint32_t nport, uint32_t data)
{
struct dma_cont *d = opaque;
int ichan;
ichan = channels[nport & 7];
if (-1 == ichan) {
dolog ("invalid channel %#x %#x\n", nport, data);
return;
}
d->regs[ichan].pageh = data;
}
static uint32_t read_page (void *opaque, uint32_t nport)
{
struct dma_cont *d = opaque;
int ichan;
ichan = channels[nport & 7];
if (-1 == ichan) {
dolog ("invalid channel read %#x\n", nport);
return 0;
}
return d->regs[ichan].page;
}
static uint32_t read_pageh (void *opaque, uint32_t nport)
{
struct dma_cont *d = opaque;
int ichan;
ichan = channels[nport & 7];
if (-1 == ichan) {
dolog ("invalid channel read %#x\n", nport);
return 0;
}
return d->regs[ichan].pageh;
}
static inline void init_chan (struct dma_cont *d, int ichan)
{
struct dma_regs *r;
r = d->regs + ichan;
r->now[ADDR] = r->base[ADDR] << d->dshift;
r->now[COUNT] = 0;
}
static inline int getff (struct dma_cont *d)
{
int ff;
ff = d->flip_flop;
d->flip_flop = !ff;
return ff;
}
static uint32_t read_chan (void *opaque, uint32_t nport)
{
struct dma_cont *d = opaque;
int ichan, nreg, iport, ff, val, dir;
struct dma_regs *r;
iport = (nport >> d->dshift) & 0x0f;
ichan = iport >> 1;
nreg = iport & 1;
r = d->regs + ichan;
dir = ((r->mode >> 5) & 1) ? -1 : 1;
ff = getff (d);
if (nreg)
val = (r->base[COUNT] << d->dshift) - r->now[COUNT];
else
val = r->now[ADDR] + r->now[COUNT] * dir;
ldebug ("read_chan %#x -> %d\n", iport, val);
return (val >> (d->dshift + (ff << 3))) & 0xff;
}
static void write_chan (void *opaque, uint32_t nport, uint32_t data)
{
struct dma_cont *d = opaque;
int iport, ichan, nreg;
struct dma_regs *r;
iport = (nport >> d->dshift) & 0x0f;
ichan = iport >> 1;
nreg = iport & 1;
r = d->regs + ichan;
if (getff (d)) {
r->base[nreg] = (r->base[nreg] & 0xff) | ((data << 8) & 0xff00);
init_chan (d, ichan);
} else {
r->base[nreg] = (r->base[nreg] & 0xff00) | (data & 0xff);
}
}
static void write_cont (void *opaque, uint32_t nport, uint32_t data)
{
struct dma_cont *d = opaque;
int iport, ichan = 0;
iport = (nport >> d->dshift) & 0x0f;
switch (iport) {
case 0x08: /* command */
if ((data != 0) && (data & CMD_NOT_SUPPORTED)) {
dolog ("command %#x not supported\n", data);
return;
}
d->command = data;
break;
case 0x09:
ichan = data & 3;
if (data & 4) {
d->status |= 1 << (ichan + 4);
}
else {
d->status &= ~(1 << (ichan + 4));
}
d->status &= ~(1 << ichan);
DMA_run();
break;
case 0x0a: /* single mask */
if (data & 4)
d->mask |= 1 << (data & 3);
else
d->mask &= ~(1 << (data & 3));
DMA_run();
break;
case 0x0b: /* mode */
{
ichan = data & 3;
#ifdef DEBUG_DMA
{
int op, ai, dir, 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 0x0c: /* clear flip flop */
d->flip_flop = 0;
break;
case 0x0d: /* reset */
d->flip_flop = 0;
d->mask = ~0;
d->status = 0;
d->command = 0;
break;
case 0x0e: /* clear mask for all channels */
d->mask = 0;
DMA_run();
break;
case 0x0f: /* write mask for all channels */
d->mask = data;
DMA_run();
break;
default:
dolog ("unknown iport %#x\n", iport);
break;
}
#ifdef DEBUG_DMA
if (0xc != iport) {
linfo ("write_cont: nport %#06x, ichan % 2d, val %#06x\n",
nport, ichan, data);
}
#endif
}
static uint32_t read_cont (void *opaque, uint32_t nport)
{
struct dma_cont *d = opaque;
int iport, val;
iport = (nport >> d->dshift) & 0x0f;
switch (iport) {
case 0x08: /* status */
val = d->status;
d->status &= 0xf0;
break;
case 0x0f: /* mask */
val = d->mask;
break;
default:
val = 0;
break;
}
ldebug ("read_cont: nport %#06x, iport %#04x val %#x\n", nport, iport, val);
return val;
}
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);
DMA_run();
}
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));
DMA_run();
}
static void channel_run (int ncont, int ichan)
{
int n;
struct dma_regs *r = &dma_controllers[ncont].regs[ichan];
#ifdef DEBUG_DMA
int dir, opmode;
dir = (r->mode >> 5) & 1;
opmode = (r->mode >> 6) & 3;
if (dir) {
dolog ("DMA in address decrement mode\n");
}
if (opmode != 1) {
dolog ("DMA not in single mode select %#x\n", opmode);
}
#endif
n = r->transfer_handler (r->opaque, ichan + (ncont << 2),
r->now[COUNT], (r->base[COUNT] + 1) << ncont);
r->now[COUNT] = n;
ldebug ("dma_pos %d size %d\n", n, (r->base[COUNT] + 1) << ncont);
}
static QEMUBH *dma_bh;
static void DMA_run (void)
{
struct dma_cont *d;
int icont, ichan;
int rearm = 0;
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);
rearm = 1;
}
}
}
if (rearm)
qemu_bh_schedule_idle(dma_bh);
}
static void DMA_run_bh(void *unused)
{
DMA_run();
}
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;
}
int DMA_read_memory (int nchan, void *buf, int pos, int len)
{
struct dma_regs *r = &dma_controllers[nchan > 3].regs[nchan & 3];
target_phys_addr_t addr = ((r->pageh & 0x7f) << 24) | (r->page << 16) | r->now[ADDR];
if (r->mode & 0x20) {
int i;
uint8_t *p = buf;
cpu_physical_memory_read (addr - pos - len, buf, len);
/* What about 16bit transfers? */
for (i = 0; i < len >> 1; i++) {
uint8_t b = p[len - i - 1];
p[i] = b;
}
}
else
cpu_physical_memory_read (addr + pos, buf, len);
return len;
}
int DMA_write_memory (int nchan, void *buf, int pos, int len)
{
struct dma_regs *r = &dma_controllers[nchan > 3].regs[nchan & 3];
target_phys_addr_t addr = ((r->pageh & 0x7f) << 24) | (r->page << 16) | r->now[ADDR];
if (r->mode & 0x20) {
int i;
uint8_t *p = buf;
cpu_physical_memory_write (addr - pos - len, buf, len);
/* What about 16bit transfers? */
for (i = 0; i < len; i++) {
uint8_t b = p[len - i - 1];
p[i] = b;
}
}
else
cpu_physical_memory_write (addr + pos, buf, len);
return len;
}
/* request the emulator to transfer a new DMA memory block ASAP */
void DMA_schedule(int nchan)
{
struct dma_cont *d = &dma_controllers[nchan > 3];
qemu_irq_pulse(*d->cpu_request_exit);
}
static void dma_reset(void *opaque)
{
struct dma_cont *d = opaque;
write_cont (d, (0x0d << d->dshift), 0);
}
static int dma_phony_handler (void *opaque, int nchan, int dma_pos, int dma_len)
{
dolog ("unregistered DMA channel used nchan=%d dma_pos=%d dma_len=%d\n",
nchan, dma_pos, dma_len);
return dma_pos;
}
/* dshift = 0: 8 bit DMA, 1 = 16 bit DMA */
static void dma_init2(struct dma_cont *d, int base, int dshift,
int page_base, int pageh_base,
qemu_irq *cpu_request_exit)
{
static const int page_port_list[] = { 0x1, 0x2, 0x3, 0x7 };
int i;
d->dshift = dshift;
d->cpu_request_exit = cpu_request_exit;
for (i = 0; i < 8; i++) {
register_ioport_write (base + (i << dshift), 1, 1, write_chan, d);
register_ioport_read (base + (i << dshift), 1, 1, read_chan, d);
}
for (i = 0; i < ARRAY_SIZE (page_port_list); i++) {
register_ioport_write (page_base + page_port_list[i], 1, 1,
write_page, d);
register_ioport_read (page_base + page_port_list[i], 1, 1,
read_page, d);
if (pageh_base >= 0) {
register_ioport_write (pageh_base + page_port_list[i], 1, 1,
write_pageh, d);
register_ioport_read (pageh_base + page_port_list[i], 1, 1,
read_pageh, d);
}
}
for (i = 0; i < 8; i++) {
register_ioport_write (base + ((i + 8) << dshift), 1, 1,
write_cont, d);
register_ioport_read (base + ((i + 8) << dshift), 1, 1,
read_cont, d);
}
qemu_register_reset(dma_reset, d);
dma_reset(d);
for (i = 0; i < ARRAY_SIZE (d->regs); ++i) {
d->regs[i].transfer_handler = dma_phony_handler;
}
}
static const VMStateDescription vmstate_dma_regs = {
.name = "dma_regs",
.version_id = 1,
.minimum_version_id = 1,
.minimum_version_id_old = 1,
.fields = (VMStateField []) {
VMSTATE_INT32_ARRAY(now, struct dma_regs, 2),
VMSTATE_UINT16_ARRAY(base, struct dma_regs, 2),
VMSTATE_UINT8(mode, struct dma_regs),
VMSTATE_UINT8(page, struct dma_regs),
VMSTATE_UINT8(pageh, struct dma_regs),
VMSTATE_UINT8(dack, struct dma_regs),
VMSTATE_UINT8(eop, struct dma_regs),
VMSTATE_END_OF_LIST()
}
};
static int dma_post_load(void *opaque, int version_id)
{
DMA_run();
return 0;
}
static const VMStateDescription vmstate_dma = {
.name = "dma",
.version_id = 1,
.minimum_version_id = 1,
.minimum_version_id_old = 1,
.post_load = dma_post_load,
.fields = (VMStateField []) {
VMSTATE_UINT8(command, struct dma_cont),
VMSTATE_UINT8(mask, struct dma_cont),
VMSTATE_UINT8(flip_flop, struct dma_cont),
VMSTATE_INT32(dshift, struct dma_cont),
VMSTATE_STRUCT_ARRAY(regs, struct dma_cont, 4, 1, vmstate_dma_regs, struct dma_regs),
VMSTATE_END_OF_LIST()
}
};
void DMA_init(int high_page_enable, qemu_irq *cpu_request_exit)
{
dma_init2(&dma_controllers[0], 0x00, 0, 0x80,
high_page_enable ? 0x480 : -1, cpu_request_exit);
dma_init2(&dma_controllers[1], 0xc0, 1, 0x88,
high_page_enable ? 0x488 : -1, cpu_request_exit);
vmstate_register (NULL, 0, &vmstate_dma, &dma_controllers[0]);
vmstate_register (NULL, 1, &vmstate_dma, &dma_controllers[1]);
dma_bh = qemu_bh_new(DMA_run_bh, NULL);
}
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