macemu/BasiliskII/src/timer.cpp
2017-10-03 21:37:24 +02:00

317 lines
6.4 KiB
C++

/*
* timer.cpp - Time Manager emulation
*
* Basilisk II (C) 1997-2008 Christian Bauer
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
* SEE ALSO
* Inside Macintosh: Processes, chapter 3 "Time Manager"
* Technote 1063: "Inside Macintosh: Processes: Time Manager Addenda"
*/
#include <stdio.h>
#include "sysdeps.h"
#include "cpu_emulation.h"
#include "main.h"
#include "macos_util.h"
#include "timer.h"
#define DEBUG 0
#include "debug.h"
// Set this to 1 to enable TMQueue management (doesn't work)
#define TM_QUEUE 0
// Definitions for Time Manager
enum { // TMTask struct
tmAddr = 6,
tmCount = 10,
tmWakeUp = 14,
tmReserved = 18
};
// Array of additional info for each installed TMTask
struct TMDesc {
uint32 task; // Mac address of associated TMTask
tm_time_t wakeup; // Time this task is scheduled for execution
bool in_use; // Flag: descriptor in use
};
const int NUM_DESCS = 64; // Maximum number of descriptors
static TMDesc desc[NUM_DESCS];
/*
* Allocate descriptor for given TMTask in list
*/
static int alloc_desc(uint32 tm)
{
// Search for first free descriptor
for (int i=0; i<NUM_DESCS; i++)
if (!desc[i].in_use) {
desc[i].task = tm;
desc[i].in_use = true;
return i;
}
return -1;
}
/*
* Free descriptor in list
*/
inline static void free_desc(int i)
{
desc[i].in_use = false;
}
/*
* Find descriptor associated with given TMTask
*/
inline static int find_desc(uint32 tm)
{
for (int i=0; i<NUM_DESCS; i++)
if (desc[i].in_use && desc[i].task == tm)
return i;
return -1;
}
/*
* Enqueue task in Time Manager queue
*/
static void enqueue_tm(uint32 tm)
{
#if TM_QUEUE
uint32 tm_var = ReadMacInt32(0xb30);
WriteMacInt32(tm + qLink, ReadMacInt32(tm_var));
WriteMacInt32(tm_var, tm);
#endif
}
/*
* Remove task from Time Manager queue
*/
static void dequeue_tm(uint32 tm)
{
#if TM_QUEUE
uint32 p = ReadMacInt32(0xb30);
while (p) {
uint32 next = ReadMacInt32(p + qLink);
if (next == tm) {
WriteMacInt32(p + qLink, ReadMacInt32(next + qLink));
return;
}
}
#endif
}
/*
* Initialize Time Manager
*/
void TimerInit(void)
{
// Mark all descriptors as inactive
for (int i=0; i<NUM_DESCS; i++)
free_desc(i);
}
/*
* Exit Time Manager
*/
void TimerExit(void)
{
}
/*
* Emulator reset, remove all timer tasks
*/
void TimerReset(void)
{
// Mark all descriptors as inactive
for (int i=0; i<NUM_DESCS; i++)
free_desc(i);
}
/*
* Insert timer task
*/
int16 InsTime(uint32 tm, uint16 trap)
{
D(bug("InsTime %08lx, trap %04x\n", tm, trap));
WriteMacInt16(tm + qType, (ReadMacInt16(tm + qType) & 0x1fff) | ((trap << 4) & 0x6000));
if (find_desc(tm) >= 0)
printf("WARNING: InsTime(): Task re-inserted\n");
else {
int i = alloc_desc(tm);
if (i < 0)
printf("FATAL: InsTime(): No free Time Manager descriptor\n");
}
return 0;
}
/*
* Remove timer task
*/
int16 RmvTime(uint32 tm)
{
D(bug("RmvTime %08lx\n", tm));
// Find descriptor
int i = find_desc(tm);
if (i < 0) {
printf("WARNING: RmvTime(%08x): Descriptor not found\n", tm);
return 0;
}
// Task active?
if (ReadMacInt16(tm + qType) & 0x8000) {
// Yes, make task inactive and remove it from the Time Manager queue
WriteMacInt16(tm + qType, ReadMacInt16(tm + qType) & 0x7fff);
dequeue_tm(tm);
// Compute remaining time
tm_time_t remaining, current;
timer_current_time(current);
timer_sub_time(remaining, desc[i].wakeup, current);
WriteMacInt32(tm + tmCount, timer_host2mac_time(remaining));
} else
WriteMacInt32(tm + tmCount, 0);
D(bug(" tmCount %d\n", ReadMacInt32(tm + tmCount)));
// Free descriptor
free_desc(i);
return 0;
}
/*
* Start timer task
*/
int16 PrimeTime(uint32 tm, int32 time)
{
D(bug("PrimeTime %08x, time %d\n", tm, time));
// Find descriptor
int i = find_desc(tm);
if (i < 0) {
printf("FATAL: PrimeTime(): Descriptor not found\n");
return 0;
}
// Extended task?
if (ReadMacInt16(tm + qType) & 0x4000) {
// Convert delay time
tm_time_t delay;
timer_mac2host_time(delay, time);
// Yes, tmWakeUp set?
if (ReadMacInt32(tm + tmWakeUp)) {
//!! PrimeTime(0) means continue previous delay
// (save wakeup time in RmvTime?)
if (time == 0)
printf("WARNING: Unsupported PrimeTime(0)\n");
// Yes, calculate wakeup time relative to last scheduled time
tm_time_t wakeup;
timer_add_time(wakeup, desc[i].wakeup, delay);
desc[i].wakeup = wakeup;
} else {
// No, calculate wakeup time relative to current time
tm_time_t now;
timer_current_time(now);
timer_add_time(desc[i].wakeup, now, delay);
}
// Set tmWakeUp to indicate that task was scheduled
WriteMacInt32(tm + tmWakeUp, 0x12345678);
} else {
// Not extended task, calculate wakeup time relative to current time
tm_time_t delay;
timer_mac2host_time(delay, time);
timer_current_time(desc[i].wakeup);
timer_add_time(desc[i].wakeup, desc[i].wakeup, delay);
}
// Make task active and enqueue it in the Time Manager queue
WriteMacInt16(tm + qType, ReadMacInt16(tm + qType) | 0x8000);
enqueue_tm(tm);
return 0;
}
/*
* Timer interrupt function (executed as part of 60Hz interrupt)
*/
void TimerInterrupt(void)
{
// Look for active TMTasks that have expired
tm_time_t now;
timer_current_time(now);
for (int i=0; i<NUM_DESCS; i++)
if (desc[i].in_use) {
uint32 tm = desc[i].task;
if ((ReadMacInt16(tm + qType) & 0x8000) && timer_cmp_time(desc[i].wakeup, now) < 0) {
// Found one, mark as inactive and remove it from the Time Manager queue
WriteMacInt16(tm + qType, ReadMacInt16(tm + qType) & 0x7fff);
dequeue_tm(tm);
// Call timer function
uint32 addr = ReadMacInt32(tm + tmAddr);
if (addr) {
D(bug("Calling TimeTask %08lx, addr %08lx\n", tm, addr));
M68kRegisters r;
r.a[0] = addr;
r.a[1] = tm;
Execute68k(addr, &r);
}
}
}
}