Bochs/bochs/iodev/pit_wrap.cc
Volker Ruppert f2f4099bc1 - small cleanups in the pit_wrap and virt_timer code
- TODO: rewrite virtual timer code to support both timer types at the same time
2011-06-04 06:40:04 +00:00

365 lines
12 KiB
C++

///////////////////////////////////////////////////////////////////////
// $Id$
/////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 2001-2009 The Bochs Project
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
// Define BX_PLUGGABLE in files that can be compiled into plugins. For
// platforms that require a special tag on exported symbols, BX_PLUGGABLE
// is used to know when we are exporting symbols and when we are importing.
#define BX_PLUGGABLE
#include "iodev.h"
#include "pit_wrap.h"
#include "virt_timer.h"
#include "speaker.h"
#define LOG_THIS thePit->
bx_pit_c *thePit = NULL;
int libpit_LTX_plugin_init(plugin_t *plugin, plugintype_t type, int argc, char *argv[])
{
thePit = new bx_pit_c();
bx_devices.pluginPitDevice = thePit;
BX_REGISTER_DEVICE_DEVMODEL(plugin, type, thePit, BX_PLUGIN_PIT);
return(0); // Success
}
void libpit_LTX_plugin_fini(void)
{
delete thePit;
}
//Important constant #defines:
#define USEC_PER_SECOND (1000000)
//1.193181MHz Clock
#define TICKS_PER_SECOND (1193181)
// define a macro to convert floating point numbers into 64-bit integers.
// In MSVC++ you can convert a 64-bit float into a 64-bit signed integer,
// but it will not convert a 64-bit float into a 64-bit unsigned integer.
// This macro works around that.
#define F2I(x) ((Bit64u)(Bit64s) (x))
#define I2F(x) ((double)(Bit64s) (x))
//USEC_ALPHA is multiplier for the past.
//USEC_ALPHA_B is 1-USEC_ALPHA, or multiplier for the present.
#define USEC_ALPHA ((double)(.8))
#define USEC_ALPHA_B ((double)(((double)1)-USEC_ALPHA))
#define USEC_ALPHA2 ((double)(.5))
#define USEC_ALPHA2_B ((double)(((double)1)-USEC_ALPHA2))
#define ALPHA_LOWER(old,new) ((Bit64u)((old<new)?((USEC_ALPHA*(I2F(old)))+(USEC_ALPHA_B*(I2F(new)))):((USEC_ALPHA2*(I2F(old)))+(USEC_ALPHA2_B*(I2F(new))))))
//PIT tick to usec conversion functions:
//Direct conversions:
#define TICKS_TO_USEC(a) (((a)*USEC_PER_SECOND)/TICKS_PER_SECOND)
#define USEC_TO_TICKS(a) (((a)*TICKS_PER_SECOND)/USEC_PER_SECOND)
bx_pit_c::bx_pit_c()
{
put("PIT");
/* 8254 PIT (Programmable Interval Timer) */
s.timer_handle[1] = BX_NULL_TIMER_HANDLE;
s.timer_handle[2] = BX_NULL_TIMER_HANDLE;
s.timer_handle[0] = BX_NULL_TIMER_HANDLE;
}
void bx_pit_c::init(void)
{
DEV_register_irq(0, "8254 PIT");
DEV_register_ioread_handler(this, read_handler, 0x0040, "8254 PIT", 1);
DEV_register_ioread_handler(this, read_handler, 0x0041, "8254 PIT", 1);
DEV_register_ioread_handler(this, read_handler, 0x0042, "8254 PIT", 1);
DEV_register_ioread_handler(this, read_handler, 0x0043, "8254 PIT", 1);
DEV_register_ioread_handler(this, read_handler, 0x0061, "8254 PIT", 1);
DEV_register_iowrite_handler(this, write_handler, 0x0040, "8254 PIT", 1);
DEV_register_iowrite_handler(this, write_handler, 0x0041, "8254 PIT", 1);
DEV_register_iowrite_handler(this, write_handler, 0x0042, "8254 PIT", 1);
DEV_register_iowrite_handler(this, write_handler, 0x0043, "8254 PIT", 1);
DEV_register_iowrite_handler(this, write_handler, 0x0061, "8254 PIT", 1);
BX_DEBUG(("starting init"));
BX_PIT_THIS s.speaker_data_on = 0;
BX_PIT_THIS s.refresh_clock_div2 = 0;
BX_PIT_THIS s.timer.init();
BX_PIT_THIS s.timer.set_OUT_handler(0, irq_handler);
Bit64u my_time_usec = bx_virt_timer.time_usec();
if (BX_PIT_THIS s.timer_handle[0] == BX_NULL_TIMER_HANDLE) {
BX_PIT_THIS s.timer_handle[0] = bx_virt_timer.register_timer(this, timer_handler, (unsigned) 100 , 1, 1, "pit_wrap");
}
BX_DEBUG(("RESETting timer."));
bx_virt_timer.deactivate_timer(BX_PIT_THIS s.timer_handle[0]);
BX_DEBUG(("deactivated timer."));
if (BX_PIT_THIS s.timer.get_next_event_time()) {
bx_virt_timer.activate_timer(BX_PIT_THIS s.timer_handle[0],
(Bit32u)BX_MAX(1,TICKS_TO_USEC(BX_PIT_THIS s.timer.get_next_event_time())),
0);
BX_DEBUG(("activated timer."));
}
BX_PIT_THIS s.last_next_event_time = BX_PIT_THIS s.timer.get_next_event_time();
BX_PIT_THIS s.last_usec = my_time_usec;
BX_PIT_THIS s.total_ticks = 0;
BX_PIT_THIS s.total_usec = 0;
BX_DEBUG(("finished init"));
BX_DEBUG(("s.last_usec="FMT_LL"d",BX_PIT_THIS s.last_usec));
BX_DEBUG(("s.timer_id=%d",BX_PIT_THIS s.timer_handle[0]));
BX_DEBUG(("s.timer.get_next_event_time=%d", BX_PIT_THIS s.timer.get_next_event_time()));
BX_DEBUG(("s.last_next_event_time=%d", BX_PIT_THIS s.last_next_event_time));
}
void bx_pit_c::reset(unsigned type)
{
BX_PIT_THIS s.timer.reset(type);
}
void bx_pit_c::register_state(void)
{
bx_list_c *list = new bx_list_c(SIM->get_bochs_root(), "pit", "8254 PIT State", 7);
new bx_shadow_bool_c(list, "speaker_data_on", &BX_PIT_THIS s.speaker_data_on);
new bx_shadow_bool_c(list, "refresh_clock_div2", &BX_PIT_THIS s.refresh_clock_div2);
new bx_shadow_num_c(list, "last_usec", &BX_PIT_THIS s.last_usec);
new bx_shadow_num_c(list, "last_next_event_time", &BX_PIT_THIS s.last_next_event_time);
new bx_shadow_num_c(list, "total_ticks", &BX_PIT_THIS s.total_ticks);
new bx_shadow_num_c(list, "total_usec", &BX_PIT_THIS s.total_usec);
bx_list_c *counter = new bx_list_c(list, "counter", 4);
BX_PIT_THIS s.timer.register_state(counter);
}
void bx_pit_c::timer_handler(void *this_ptr)
{
bx_pit_c * class_ptr = (bx_pit_c *) this_ptr;
class_ptr->handle_timer();
}
void bx_pit_c::handle_timer()
{
Bit64u my_time_usec = bx_virt_timer.time_usec();
Bit64u time_passed = my_time_usec-BX_PIT_THIS s.last_usec;
Bit32u time_passed32 = (Bit32u)time_passed;
BX_DEBUG(("entering timer handler"));
if(time_passed32) {
periodic(time_passed32);
}
BX_PIT_THIS s.last_usec = BX_PIT_THIS s.last_usec + time_passed;
if (time_passed || (BX_PIT_THIS s.last_next_event_time != BX_PIT_THIS s.timer.get_next_event_time())) {
BX_DEBUG(("RESETting timer"));
bx_virt_timer.deactivate_timer(BX_PIT_THIS s.timer_handle[0]);
BX_DEBUG(("deactivated timer"));
if(BX_PIT_THIS s.timer.get_next_event_time()) {
bx_virt_timer.activate_timer(BX_PIT_THIS s.timer_handle[0],
(Bit32u)BX_MAX(1,TICKS_TO_USEC(BX_PIT_THIS s.timer.get_next_event_time())),
0);
BX_DEBUG(("activated timer"));
}
BX_PIT_THIS s.last_next_event_time = BX_PIT_THIS s.timer.get_next_event_time();
}
BX_DEBUG(("s.last_usec="FMT_LL"d", BX_PIT_THIS s.last_usec));
BX_DEBUG(("s.timer_id=%d", BX_PIT_THIS s.timer_handle[0]));
BX_DEBUG(("s.timer.get_next_event_time=%x", BX_PIT_THIS s.timer.get_next_event_time()));
BX_DEBUG(("s.last_next_event_time=%d", BX_PIT_THIS s.last_next_event_time));
}
// static IO port read callback handler
// redirects to non-static class handler to avoid virtual functions
Bit32u bx_pit_c::read_handler(void *this_ptr, Bit32u address, unsigned io_len)
{
#if !BX_USE_PIT_SMF
bx_pit_c *class_ptr = (bx_pit_c *) this_ptr;
return class_ptr->read(address, io_len);
}
Bit32u bx_pit_c::read(Bit32u address, unsigned io_len)
{
#else
UNUSED(this_ptr);
#endif // !BX_USE_PIT_SMF
Bit8u value = 0;
handle_timer();
Bit64u my_time_usec = bx_virt_timer.time_usec();
switch (address) {
case 0x40: /* timer 0 - system ticks */
value = BX_PIT_THIS s.timer.read(0);
break;
case 0x41: /* timer 1 read */
value = BX_PIT_THIS s.timer.read(1);
break;
case 0x42: /* timer 2 read */
value = BX_PIT_THIS s.timer.read(2);
break;
case 0x43: /* timer 1 read */
value = BX_PIT_THIS s.timer.read(3);
break;
case 0x61:
/* AT, port 61h */
BX_PIT_THIS s.refresh_clock_div2 = (bx_bool)((my_time_usec / 15) & 1);
value = (BX_PIT_THIS s.timer.read_OUT(2) << 5) |
(BX_PIT_THIS s.refresh_clock_div2 << 4) |
(BX_PIT_THIS s.speaker_data_on << 1) |
(BX_PIT_THIS s.timer.read_GATE(2) ? 1 : 0);
break;
default:
BX_PANIC(("unsupported io read from port 0x%04x", address));
}
BX_DEBUG(("read from port 0x%04x, value = 0x%02x", address, value));
return value;
}
// static IO port write callback handler
// redirects to non-static class handler to avoid virtual functions
void bx_pit_c::write_handler(void *this_ptr, Bit32u address, Bit32u dvalue, unsigned io_len)
{
#if !BX_USE_PIT_SMF
bx_pit_c *class_ptr = (bx_pit_c *) this_ptr;
class_ptr->write(address, dvalue, io_len);
}
void bx_pit_c::write(Bit32u address, Bit32u dvalue, unsigned io_len)
{
#else
UNUSED(this_ptr);
#endif // !BX_USE_PIT_SMF
Bit8u value;
Bit64u my_time_usec = bx_virt_timer.time_usec();
Bit64u time_passed = my_time_usec-BX_PIT_THIS s.last_usec;
Bit32u time_passed32 = (Bit32u)time_passed;
if(time_passed32) {
periodic(time_passed32);
}
BX_PIT_THIS s.last_usec = BX_PIT_THIS s.last_usec + time_passed;
value = (Bit8u) dvalue;
BX_DEBUG(("write to port 0x%04x, value = 0x%02x", address, value));
switch (address) {
case 0x40: /* timer 0: write count register */
BX_PIT_THIS s.timer.write(0, value);
break;
case 0x41: /* timer 1: write count register */
BX_PIT_THIS s.timer.write(1, value);
break;
case 0x42: /* timer 2: write count register */
BX_PIT_THIS s.timer.write(2, value);
break;
case 0x43: /* timer 0-2 mode control */
BX_PIT_THIS s.timer.write(3, value);
break;
case 0x61:
BX_PIT_THIS s.speaker_data_on = (value >> 1) & 0x01;
if (BX_PIT_THIS s.speaker_data_on) {
DEV_speaker_beep_on((float)(1193180.0 / BX_PIT_THIS get_timer(2)));
} else {
DEV_speaker_beep_off();
}
/* ??? only on AT+ */
BX_PIT_THIS s.timer.set_GATE(2, value & 0x01);
break;
default:
BX_PANIC(("unsupported io write to port 0x%04x = 0x%02x", address, value));
}
if (time_passed || (BX_PIT_THIS s.last_next_event_time != BX_PIT_THIS s.timer.get_next_event_time())) {
BX_DEBUG(("RESETting timer"));
bx_virt_timer.deactivate_timer(BX_PIT_THIS s.timer_handle[0]);
BX_DEBUG(("deactivated timer"));
if(BX_PIT_THIS s.timer.get_next_event_time()) {
bx_virt_timer.activate_timer(BX_PIT_THIS s.timer_handle[0],
(Bit32u)BX_MAX(1,TICKS_TO_USEC(BX_PIT_THIS s.timer.get_next_event_time())),
0);
BX_DEBUG(("activated timer"));
}
BX_PIT_THIS s.last_next_event_time = BX_PIT_THIS s.timer.get_next_event_time();
}
BX_DEBUG(("s.last_usec="FMT_LL"d", BX_PIT_THIS s.last_usec));
BX_DEBUG(("s.timer_id=%d", BX_PIT_THIS s.timer_handle[0]));
BX_DEBUG(("s.timer.get_next_event_time=%x", BX_PIT_THIS s.timer.get_next_event_time()));
BX_DEBUG(("s.last_next_event_time=%d", BX_PIT_THIS s.last_next_event_time));
}
bx_bool bx_pit_c::periodic(Bit32u usec_delta)
{
Bit32u ticks_delta = 0;
BX_PIT_THIS s.total_usec += usec_delta;
ticks_delta = (Bit32u)((USEC_TO_TICKS((Bit64u)(BX_PIT_THIS s.total_usec)))-BX_PIT_THIS s.total_ticks);
BX_PIT_THIS s.total_ticks += ticks_delta;
while ((BX_PIT_THIS s.total_ticks >= TICKS_PER_SECOND) && (BX_PIT_THIS s.total_usec >= USEC_PER_SECOND)) {
BX_PIT_THIS s.total_ticks -= TICKS_PER_SECOND;
BX_PIT_THIS s.total_usec -= USEC_PER_SECOND;
}
while(ticks_delta>0) {
Bit32u maxchange = BX_PIT_THIS s.timer.get_next_event_time();
Bit32u timedelta = maxchange;
if((maxchange == 0) || (maxchange>ticks_delta)) {
timedelta = ticks_delta;
}
BX_PIT_THIS s.timer.clock_all(timedelta);
ticks_delta -= timedelta;
}
return 0;
}
void bx_pit_c::irq_handler(bx_bool value)
{
if (value == 1) {
DEV_pic_raise_irq(0);
} else {
DEV_pic_lower_irq(0);
}
}
Bit16u bx_pit_c::get_timer(int Timer) {
return BX_PIT_THIS s.timer.get_inlatch(Timer);
}